Technical Field
[0001] The present invention relates to a mobile communication system sharing of a frequency
channel or a time slot and using a time division multiple access system (hereinafter
referred to as TDMA) and/or a time division, code division multiple access system
(hereinafter referred to as time divided CDMA), and in particular, it relates to a
mobile communication system comprising a function in which a set of links, an up-link
and a down-link, having different communication capacities from each other may be
handled as a single communication channel (hereinafter referred to as an asymmetric
communication channel).
Background Art
[0002] A mobile communication system is mainly constituted with a mobile communication equipment
or a portable communication equipment and a base station which communicates with mobile
stations through radio channels. In such a mobile communication system, the common
use of a radio frequency spectrum by different radio systems may be executed in a
frequency division multiple access system (hereinafter referred to as an FDMA) or
between a TDMA system and a CDMA system.
[0003] The common use of a frequency channel by different code systems has been put into
an actual operation concerning the CDMA system.
[0004] A mobile communication system of a time slot common use type in which at least a
TDMA signal and at least a time divided CDMA signal coexist in a time slot is disclosed
in
U.S. application No. 08/524,974 which is separately applied by the same applicant as the present invention, however,
an asymmetrical communication channel is not all at referred to in the application.
[0005] Technologies for mobile communication systems in which a time slot is commonly used
and a frequency channel is also commonly used, and further, technologies for synchronizing
radio base stations by a wireless local loop (hereinafter referred to as WLL) using
semi-fixed communication equipment are known in the art. However, in these technologies,
an asymmetric channel in which capacities of an up-link and a down-link are different
is not known.
[0006] The
U.S. patent No. 5,363,403 is known as a system in which a plurality of CDMA signals are commonly used. However,
in the specification, nothing is described concerning the way of handling a time divided
CDMA. The
U.S. patent No.5,511,068 is also known as another mobile communication system, however, it is related to an
adaptive filter in a time divided CDMA system and in the specification nothing is
nothing refers to the common use of a frequency channel of a CDMA signal and a TDMA
signal in a single time slot.
[0007] As a communication system in which a TDMA technology is applied to a CDMA communication
system, the
U.S. patent No. 5,410,568 is known. In the patent, a synchronization code is placed at the head of a burst
signal. The patent does not refer to a system in which a time divided CDMA system
is introduced using a TMDA control channel for setting frame synchronization, and
nothing refers to coexistence with a TDMA system. In other words, it is not a patent
in which TDMA system and a time divided CDMA system are to be used in common using
a TDMA frame. Further, no consideration is paid for an asymmetrical channel in which
the capacity of an up-channel is different from that of a downchannel.
[0009] However, in the above-mentioned
JP-A-63/175526 and
JP-A-63/175527, it is intended to send more signals under the condition that the transmitting power
of a transponder in a satellite communication is limited, but in the case of a mobile
communication on land, such a limitation does not exist. Furthermore nothing describes
a time divided CDMA system or a high speed TDMA.
JP-A-5/145477 is related to the control of transmitting power of a signal in a TDMA time slot,
and nothing refers to the time divided CDMA and TDMA communication systems.
[0010] The above-mentioned
JP-A-7/154866 and
JP-A-8/186533 are applications in which a set of links, an up-link and a down-link of having different
capacities from each other may be handled as a communication channel. In the former,
however; there is no concrete description about a high speed TDMA data transmission
or a low speed time-divided CDMA data/voice frequency signal transmission, and nothing
refers to a control information channel for intermittent connection which connects
a user and a database during the consideration of the user or to the increase or decrease
of a guard time in the unit of a micro time slot in a high speed TDMA data transmission
channel. In the latter, as understood from the explanation of an aloha with a slot,
it is premised on a packet communication system, and the time ratio of an up-link
to a downlink in a time division duplex communication system can be variable, but
it does not vary the time ratio of the up-link to down-link in a TDMA-TDD frame. Therefore,
nothing refers to the coexistence of a plurality of TDMA signals, high speed TDMA
data transmission and time divided CDMA in a time slot.
[0011] The article "A Wireless Multimedia Network on a Time Division Duplex CDMA/TDMA" by
K. Seki et al. discloses a TDD system with a fixed low speed CDMA channel in uplink
and a high speed TDMA channel in downlink.
[0012] As mentioned in the above, there are many kinds of systems being constituted of one
or more base stations which communicate with a plurality of mobile stations through
radio channels using a TDMA system and a time divided CDMA system have been known.
In these mobile communication systems, there has been a demand to introduce a high
speed data communication system, however, a mobile communication system which is able
to correspond such a demand has not been realized.
[0013] In order to make a mobile communication system to be able to correspond to a multimedia
communication, it is needed to introduce a communication channel in which the communication
capacity in an up-link and that in a down-link are different.
[0014] The present invention was made to solve the problems as mentioned in the above, and
the object of the present invention is to realize a mobile communication system which
is able to correspond to a multimedia environment, wherein a high speed TDMA channel
is introduced to a mobile communication system in which a TDMA signal and a time divided
CDMA signal coexist, and furthermore, communication links having different communication
capacities in an up-link and a down-link may be handled as a single communication
channel.
Disclosure of the Invention
[0015] A mobile communication system is described in claim 1, which comprises:
a plurality of mobile stations and at least one base station, said mobile stations
and said base station being radio-connected to each other using a multiple access
system being a combination of TDMA, FDMA and CDMA and the up-link and down-link being
separated in a Time Division Duplex TDD manner.
[0016] At least one of said plurality of mobile stations is capable of selecting between
a low speed CDMA data transmission function or a high speed TDMA data transmission
function for radio-connection to said base station, and wherein the communication
channel in said mobile communication system is constituted by an asymmetric channel.
[0017] The information quantity to be transmitted in either of the uplink or the downlink
is not fixed, and dependent upon system requirements the uplink information quantity
can be greater or less than that in the downlink. Further, the choice between a high
speed TDMA or a low speed CDMA multiple access scheme in both the uplink or downlink
directions is determined according to the actual information quantity to be transmitted.
[0018] Preferred embodiments of the invention are claimed in the dependent claims.
Brief Description of the Drawings
[0019]
Fig. 1 shows a constitutional drawing which shows the whole constitution of a mobile
communication system in an embodiment 1 according to the present invention.
Fig. 2 shows an illustrative drawing showing a personal communication system (hereinafter
referred to as PCS) of time divided CDMA, and a time slot constitution for a cellular
in the embodiment 1 according to the present invention.
Fig. 3 shows an illustrative drawing showing a time slot constitution which has a
different form from that shown in Fig. 2 in the embodiment 1.
Fig. 4 shows an illustrative drawing showing an example of an asymmetric data communication
channel being composed of a high speed TDMA data channel and a time divided CDMA channel
shown in Fig. 3 in the embodiment 1.
Fig. 5 shows a flow chart showing a control process of a system having an asymmetric
channel in an embodiment 2 according to the present invention.
Fig. 6 shows an illustrative drawing showing the constitution of a time divided CDMA
burst for PCS in an embodiment 3 according to the present invention.
Fig. 7 shows an illustrative drawing showing a multi-frame constitution of a time
divided CDMA burst for PCS in the embodiment 3.
Fig. 8 shows an illustrative drawing showing the constitution of an intermittent connection
control channel in a multi-frame of a time divided CDMA burst for PCS in the embodiment
3.
Fig. 9 shows an illustrative drawing showing the constitution of a micro time slot
in a high speed TDMA data channel in an embodiment 4 according to the present invention.
Fig. 10 shows a block diagram showing the constitution of a mobile station in an embodiment
5 according to the present invention.
Fig. 11 shows a block diagram showing the constitution of a base station in the embodiment
5.
Fig. 12 shows a block diagram showing an interface unit on the side of a mobile switching
center in a base station in the embodiment 5.
Fig. 13 shows an illustrative drawing showing the time slot assignment of a switch
for the selection of a communication system of an interface unit in a base station
in the embodiment 5.
Fig. 14 shows a block diagram showing the constitution of a mobile switching center
in an embodiment 6 according to the present invention.
Fig. 15 shows an illustrative drawing showing an example of a mobile station information
which is registered in a mobile unit information memory shown in the embodiment 6.
Fig. 16 shows a block diagram showing the constitution of a mobile switching center
in an embodiment 7 according to the present invention.
Fig. 17 shows an illustrative drawing showing relevant information which is necessary
for the management of the contents of a memory device for a high speed communication
in the embodiment 7.
Fig. 18 shows a flow chart of the control process of the memory device for high speed
communication in the embodiment 7.
Fig. 19 shows an illustrative drawing showing an example of a communication channel
management list of a mobile station in an embodiment 8 in the present invention.
Best Mode for Carrying Out the Invention
[0020] In order to explain the present invention more in detail, embodiments according to
the present invention will be explained referring the attached drawings.
Embodiment 1
[0021] Fig. 1 is a schematic figure of the whole constitution of a mobile communication
system to which the common use system of a time slot and the common use system of
a frequency channel according to the present invention may be applied. In the drawing,
reference numerals 1, 2 and 3 denote base stations, and 4 and 5 denote the covering
areas (hereinafter referred to as a cell) of the base stations 1 and 2. A cell 4 includes
zones 11, 12 and 13, and a cell 5 includes zones 21, 22 and 23.
[0022] Reference numerals 31, 32, 33 and 34 denote ordinary mobile stations (MS) with conventional
movable communication equipment, such as mobile communication equipment or portable
communication equipment in which the main business is a voice-frequency communication
to communicate with the base stations 1 and 2, through radio channels and 41 and 42
are WLL stations (WS) which communicate with base stations 1 and 2 through radio channels.
Reference numerals 51 and 52 are multimedia stations (DS), that is, mobile stations
or semi-fixed stations which communicate with base stations 1 to 3, through medium/high
data-speed TDMA channels. These multimedia stations 51 and 52 comprise the function
to perform voice frequency communication or low-speed data communication through a
time-divided CDMA channel or a low-speed TDMA data channel besides the above-mentioned
medium/high data-speed TDMA channel. In the following explanation, an ordinary mobile
station (MS), a WLL station (WS) and a multimedia station (DS) are generally called
a mobile station.
[0023] A reference numeral 6 denotes a mobile switching center (MSC) which controls the
base stations 1 and 3, and 7 denotes a mobile switching center which controls the
base station 2. A reference numeral 8 denotes a public switching telephone network
(PSTN) which connects mobile switching centers 6 and 7 by wire.
[0024] The embodiment 1 relates to a TDMA/time-divided CDMA mobile communication system
including mobile stations which communicate with a base station through medium/high-speed
TDMA channel. The frame constitution of a mobile communication system comprising a
TDMA/time-divided CDMA channel, a high-speed TDMA data transmission channel, and an
asymmetric channel will be explained in the following.
[0025] In the mobile communication system according to the present invention, mobile stations
such as ordinary mobile stations 31 to 34, WLL stations 41 and 42, and multimedia
stations 51 and 52, and base stations 1 and 2 are connected by radio systems such
as FDMA/time-divided duplex (hereinafter referred to as TDD) system, multi-carriers
TDMA system, CDMA/TDD system, TDMA/frequency-divided duplex system (FDD), TDMA/TDD
system, time divided CDMA/FDD system, or time-divided CDMA/TDD system using signals
modulated by digital modulation systems such as frequency shift keying (FSK), phase
shift keying (PSK) such as BPSK, QPSK, DQPSK, π/4-DSPSK, and so on or minimum shift
keying (MSK) such as QAMSK, QGMSK, and so on.
[0026] A mobile communication system in the embodiment 1 according to the present invention
in which a plurality of multimedia stations and a plurality of base stations having
a high-speed TDMA transmission function are connected with a high-speed TDMA transmission
channel is a mobile communication system of time slot common use and frequency channel
common use comprising CDMA signal channel (hereinafter referred to as a common channel)
which commonly uses a time slot and a frequency channel with a FDMA/TDMA digital signal
on the frequency axis, and is a WLL and movable communication system of a time slot
common use and a frequency channel common use comprising a time divided CDMA signal
which commonly uses a time slot and a frequency channel (a case where frequency channel
is not commonly uses is included) with the TDMA signal.
[0027] Fig. 2 shows an illustrative drawing showing PCS by a time divided CDMA and the constitution
of a time slot for a cellular, in the above only those in the down-link of TDD is
shown. In the drawing, # 61-0 to # 61-3 show time slots for PCS, and # 67-0 and #
67-3 show time slots for cellular. Also in the drawing, # 64-0 and # 64-3 show time
slots for medium-speed TDMA data communication, and # 66-1 and # 66-2 show time slots
for high-speed TDMA data communication. Other time slots for low-speed TDMA marked
with "*" , # 62-0 to # 62-3, # 63-1 and # 63-2, and # 65-0 to 65-3 show an example
being used for a voice-frequency data channel, a low-speed data channel, or a control
channel.
[0028] In the embodiment 1, when a channel is used as a control channel, it comprises at
least one TDMA burst signal and/or at least one time divided CDMA burst signal.
[0029] Fig. 3 is an illustrative drawing showing a time slot constitution of a different
form from that shown in Fig. 2, and it shows a state where the down-link T is added
in an asymmetric mobile communication system such as a high-speed TDMA data transmission
system in which transmission capacity of the up-link is different from that of down-link.
In the drawing, parts denoted by the same reference numerals as those shown in Fig.
2 have the same functions, so that the explanation of them will be omitted. In the
drawing, # 71-T0 to # 71-T3, and# 71-T7A, # 71-T7B and# 71-T7C are time slots for
high-speed TDMA data communication assigned to the down link from a base station to
mobile stations, and # 71-R0 to # 71-R2 are time slots to be used for the up-link
from mobile stations to the base station.
[0030] In Fig. 3, a reference numeral 72 denotes one frame length, and 73 and 74 denote
half-frame lengths of a time divided CDMA channel, a low-speed TDMA channel and a
medium-speed TDMA channel in the above-mentioned frame. A reference numeral 75 denotes
a frame length (4 + 1 time-slot length) for the down-link from a base station to mobile
stations, and 76 denotes a frame length (3 time-slot length) of a high-speed TDMA
data channel for the up-link from mobile stations to a base station. Reference numerals
77 and 78 are TDD lines shown in a chart expressed by frame time axis and frequency
axis which forms a border line between the down-link from a base station to mobile
stations and the up-link from mobile stations to the base station.
[0031] In this case, there is asymmetry between the up-link and the down-link where respective
channels have different transmission capacities from each other. In an ordinary case,
the up-link from mobile stations to a base station, and the down-link from a base
station to mobile stations have the same transmission capacity. Asymmetric high-speed
TDMA data transmission channels, # 71-T0 to # 71-T3, #71-T7A, # 71-T7B and # 71-T7C,
and # 71-R0 to # 71-R2 as shown in Fig. 3 show an example of time slot constitution
for realizing the above-mentioned request. The process of occurrence of such circumstances
will be explained in the following.
[0032] Multimedia is the subject of a mobile communication system in the embodiment 1, and
in particular the case where the down-link of a high-speed TDMA data channel may be
used for the transmission of a large quantity of data to users such as image information
or data bank information will be considered. In such a case, when a user accesses
to a data bank or a home page, the down-link is useful for the transmission of a large
quantity of data from a data source to the user in a short time. On the other hand,
even when a user receives such a large quantity of data it will be rare that he reads
and understands and reaches a conclusion immediately and send the data back to the
above-mentioned originating source of the data, and in particular when the user is
a natural person such a case will be difficult to consider.
[0033] In other words, after the reception of a large quantity of data by a personal user
a long period of time is generally necessary before answering data is sent back. Therefore,
even though a transmission channel for a large quantity of data is needed for a down-link,
just right after the reception of the large quantity of data there will be no need
to set a transmission channel for a large quantity of data in the up-link. Accordingly,
asymmetry in data transmission capacity occurs temporarily between the up-link and
the down-link; therefore, it is necessary to have a time slot constitution being matched
to the circumstances. An example of it will be shown in Fig. 4.
[0034] Fig. 4 is an illustrative drawing showing an example of an asymmetric data communication
channel composed of a high-speed TDMA data channel and a time-divided CDMA channel
shown in Fig. 3 in a TDD system. According to the example shown in Fig. 4, one frame
length is 5 ms and a half-frame length of 2.5 ms is assigned to the down-link and
the same is assigned to the up-link. The down-link is a high-speed TDMA data channel
and the information transmission rate is 1.024 Mb/s. The up-link is a low-speed time
divided CDMA data channel and the information transmission rate is 32 kb/s.
[0035] In the above explanation, an asymmetric channel is shown in which the down-link from
a base station to a mobile station is a high-speed TDMA data channel and the up-link
from the mobile station to the base station is a low-speed time divided CDMA data
channel; however another asymmetric channel is also possible which is composed of
a down-link of a high-speed TDMA data channel and a up-channel of a low-speed TDMA
data channel.
[0036] Besides the above-mentioned asymmetric channels, an asymmetric channel composed of
a down-link of a low-speed data channel and an up-link of a high-speed TDMA data channel,
or another asymmetric channel composed of a down-link of a low-speed time-divided
CDMA data channel and an up-link of a high-speed TDMA data channel are also possible.
[0037] In the case of the mobile communication system in the embodiment 1 as explained in
the above, if the system is a TDD system, the ratio of the total information quantity
in down-links transmitted from the base station to the total information quantity
in up-links received by the base station may be varied by shifting the TDD line 77
or 78 in the direction of the time axis, the TDD line which is shown in the chart
defined by the frame time axis and the frequency axis as shown in Fig. 3 and forms
the border between the down-links and the up-links.
[0038] The management of the asymmetric communication channel is performed by mobile switching
centers 6 and 7, and the change in the ratio of information quantity in the up-link
to that in the down-link is instructed by the mobile switching center 6 or 7 to at
least one base station 1, 3 or 2.
[0039] As explained in the above, according to the embodiment 1, by organizing the systems,
(a low-speed TDMA system being commonly used by low-speed data communication and voice
frequency communication, a time divided CDMA system being commonly used by low-speed
data communication and voice-frequency communication, and a high-speed TDMA system
for high-speed data communication), into one system, the switching over of communication
speed in the unit of a frame length (5 ms in the example shown in Fig. 4) required
by users may be realized, and also by adopting different systems for the down-link
and the up-link from each other, that is, by setting an asymmetric communication channel,
a mobile communication system is realized which is able to flexibly respond to changes
in communication capacity, which makes the system suitable for use with multimedia.
[0040] In the above description, a case where a high-speed TDMA data channel is used as
a high-speed data channel for transmitting a large quantity of data was shown, however,
as a high-speed data channel a high-speed time divided CDMA data channel, and so on
may be used and the same effect as that obtained in the embodiment 1 is obtained.
Embodiment 2
[0041] In the following, the control process of a mobile communication system having an
asymmetric channel shown in the embodiment 1 will be explained as an embodiment 2.
[0042] Fig. 5 shows a flow chart showing the control process in a mobile communication system
having an asymmetric channel in the embodiment 2 according to the present invention.
In a mobile station when power is made on and the access to a mobile communication
system is started, in step ST1, a TDMA control channel is set between a mobile station
and a base station to communicate control data necessary for the communication between
them. In other words, the mobile station receives control data from the subject base
station through the TDMA control channel and transmits a signal to the designated
time slot through a up-link TDMA control channel. The position of a received burst
is measured in the base station, and the deviation information from the designated
position of the time slot is transmitted to the mobile station, and the burst position
in the up-link is corrected based on the deviation information. Thus the synchronization
is established. At the same time, information concerning channel setting is also exchanged.
[0043] When the setting of the TDMA control channel is finished, in the step ST2, a large
quantity of data is transmitted from the base station to the mobile station through
the high-speed TDMA data channel. In this case, the up-link and the down-link do not
form an equal duplex operation system as in an ordinary telephone system, and in step
ST2, only in the down-link a large quantity of data is transmitted from the base station
to the mobile station through the high-speed TDMA data channel. While the data are
being transmitted in the down-link, in the up-link, the information of the quantity
of the same order as in the case of an ordinary voice frequency digital signal may
be transmitted. In this case, a time divided CDMA channel or a low-speed TDMA data
channel is used for the up-link. In this way, in the down-link a large quantity of
data is transmitted and in the up-link a small quantity of data is transmitted, thus
an imbalance in the transmission capacity between the up-link and the down-link occurs,
which produces asymmetry in the channel.
[0044] In a step ST3, after the transmission of a large quantity of data in the down-link
in step ST2 is finished until the transmission of a large quantity of data is started
in the up-link, the base station and the mobile station are kept being connected with
a data transmission channel of a small data transmission capacity. In other words,
when the transmission of a large quantity of TDMA data is finished, the connection
between the base station and the mobile station is continued using a time divided
CDMA channel as a up-link and using a corresponding time divided CDMA channel for
the down-link, and necessary data may be exchanged. In the drawing, an example is
shown in which the base station and the mobile station are connected with a time divided
CDMA channel, however a low-speed TDMA data channel may be also used.
[0045] As mentioned in the above, for example, in the case where a user in a mobile station
(multimedia terminal) receives a large quantity of image data through the high-speed
TDMA data channel and the image is displayed on the screen of the multimedia terminal,
and the response concerning the contents of the image is required, it unlikely that
the user would be able to give a response immediately as it would require the transmission
of a large quantity of data. Thus a period of time of consideration is needed for
the user. However the period of time for the response will not be given, so that,
in most cases, an immediate request to set an up-link does not occur. In the step
ST3, during a period of time until the transmission of a large quantity of data to
the up-link, the base station and the mobile station are connected with a data transmission
channel of a small capacity, a time divided CDMA channel for example.
[0046] Next in step ST4, it is judged that whether communication is executed or not, and
if it is, it is also judged whether communication is being executed with a large quantity
of data or not. As a result, if communication is executed by the transmission of a
small quantity of data, the process is brought back to step ST3 and transmission of
small quantity of data, that is, the communication through the time divided CDMA channel
is continued. Otherwise if the communication is executed by the transmission of a
large quantity of data, the process is brought back to step ST2, and data transmission
of a large information quantity through a high-speed TDMA data channel is resumed.
[0047] On the other hand, if it is judged that there is no communication, the process is
advanced to step ST5 and if there is no communication for a further predetermined
time (one minute, for example) the connection between the mobile station and the base
station is moved to a control channel for connection composed of a time divided CDMA
control channel or a low-speed TDMA control channel for intermittent connection (hereinafter
referred to as a control information channel for intermittent connection) which transmits
only control data in both up-link and down-link. It may be considered that there is
no data being transmitted practically (except control data for connection) in both
up-link and down-link in a case such as a period of time while a user is under consideration.
The control information channel for intermittent connection is set in the case as
mentioned in the above. The control information channel for intermittent connection
will be explained in detail in the next embodiment 3.
[0048] In the case of a control information channel for intermittent connection shown in
step ST5, the communication of control data between a base station and a mobile station
is executed once in one multi-frame (for example, 40 frames are made to be one multiframe)
through a time divided CDMA control channel. Therefore, by one channel of the time
divided CDMA control channel 40 mobile stations may be kept in a state of being connected
(however, transmission of information data is suspended).
[0049] Next in the step ST6, it is judged whether a mobile station and a base station are
connected or not, and if they are not connected, the series of processes are finished.
On the other hand, if they are being connected, the same judgment as that in step
ST4 is performed in step ST7. In the result, in a case where it is judged that there
is no communication, the process is brought back to step ST5 and the connection with
a control information channel for intermittent connection is continued. On the other
hand, in a case where it is judged that the communication is executed by the transmission
of a small quantity of data, the process is brought back to step ST3 and the communication
is executed through a time divided CDMA channel, and in a case where it is judged
that the communication is executed by the transmission of a large quantity of data,
the process is brought back to step ST2 and the transmission of a large information
quantity of data through a high-speed TDMA data channel is resumed.
[0050] The management of switching of the asymmetric channels is performed by mobile switching
centers 6 and 7. The instruction for switching from a data transmission channel for
a large quantity of data (high-speed TDMA data channel) to a data transmission channel
for a small quantity of data (time divided CDMA channel or low-speed TDMA channel),
from a data transmission channel for a small quantity of data to a control information
channel for intermittent connection or to a data transmission channel for a large
quantity of data, or further from a control information channel for intermittent connection
to a data transmission channel for a large quantity of data or to a data transmission
channel for a small quantity of data is given from the mobile switching center 6 or
7 to at lease one base station 1, 3 or 2.
[0051] As mentioned in the above, according to the embodiment 2, there is a merit that the
useless occupation of a communication channel of large transmission capacity in a
period of time when data are not actually transmitted may be avoided by switching
the data transmission channel of a large transmission capacity to another channel
having different transmission capacity right after the finish of transmission of a
large quantity of data.
Embodiment 3
[0052] The constitution of a control information channel for intermittent connection used
as a control channel for connection described in the embodiment 2 will be explained
as an embodiment 3 according to the present invention.
[0053] Fig. 6 shows an illustrative drawing showing the structure of a CDMA burst for PCS
in the embodiment 3 according to the present invention which shows an example of numerical
values corresponding to a part of the time divided CDMA shown in Fig. 3. Fig. 7 shows
an illustrative drawing showing multi-frame constitution of a time divided CDMA burst
for PCS in the embodiment 3 which shows an example of numerical values corresponding
to time divided CDMA frames shown in Fig. 6. Fig. 8 shows an illustrative drawing
showing the constitution of a control information channel for intermittent connection
in a multi-frame of a time divided CDMA burst for PCS in the embodiment 3, and an
example of numerical values corresponding to a time divided CDMA multi-frame is shown
in Fig. 7.
[0054] The above-mentioned Fig. 6 shows an example of a time divided CDMA channel, and it
is possible to assign 32 telephone channels of 32 kb/s at the maximum by code split
technics to the time slot # 61-0 for the time divided CDMA. In one of the 32 telephone
channels is used once in a multi-frame (in the example shown in Fig. 7, 1 multi-frame
is composed of 40 frames) as shown in Fig. 7, 40 control information channels for
intermittent connection of an information rate of 800 b/s may be formed. The control
information channels for intermittent connection are formed with a data transmission
channel for a small quantity of data having an up-link and a down-link of the same
information transmission capacity. In a mobile station having 40 users, the control
information channel for intermittent connection may be used as a connection channel
while data transmission of a large information quantity is suspended.
[0055] At a multimedia terminal of a mobile station, considerable time will be needed until
a user finishes processing a large quantity of received information or after the reception
of image data of a large information quantity until the image is displayed on a screen
and processing is finished. When there is no need to transmit a large quantity of
data at a given moment, if a control information channel for intermittent connection
is connected between the mobile station and the base station it is easy to resume
transmission of any information data of a large or small quantity.
[0056] As mentioned in the above, the control information channel for intermittent connection
is a method of transmission utilizing a multi-frame system, and because of its very
small capacity, an operator (A communication company, an owner of a communication
system for offering communication services, is generally called an operator.) might
be able to offer a service in which a user is able to use the channel free of charge,
and such a service may be considered reasonable by users. While the control information
channel for intermittent connection is operated, the user is under consideration,
however, the user's terminal is kept being connected with a database or an offerer
of information, that is, the user is not in a state where he has finished his work
cutting off power supply.
[0057] A period of time until the process of a large quantity of data received by the user
is finished, that is, a period of time while the user of the multimedia system is
under consideration, it is also good to transmit control data showing that data are
not being transmitted through the control information channel for intermittent connection.
[0058] The management of the control information channel for intermittent connection is
performed by the mobile switching center, 6 or 7, and the starting, switching or suspension
of the control information channel for intermittent connection is instructed by the
mobile switching center 6 or 7, to at least one of the base stations 1, 3 or 2.
[0059] As mentioned in the above, according to the embodiment 3, the advantage is obtained
that adverse influences upon the depth or length of consideration of a user caused
by hardware may be avoided by connecting the user and a database offerer or the like
with a minimum control data channel during a period of time spent for the judgment
of the user based on the information displayed on the display unit of a multimedia
terminal of a mobile station by transmitting control data using a control information
channel for intermittent connection utilizing a multi-frame. If an operator offers
such a service that during the use of a control information channel for intermittent
connection which transmits a minimum control data no charge is collected, the above-mentioned
merit will be further effective.
Embodiment 4
[0060] Next, as an embodiment 4 according to the present invention, the constitution of
a high-speed TDMA data channel as a high-speed data channel will be explained.
[0061] Fig. 9 shows an illustrative drawing showing the constitution of a micro time slot
in a high-speed TDMA data channel in an embodiment 4 according to the present invention,
and the drawing shows the constitution of a high-speed TDMA data channel #71 shown
in Fig. 3 and Fig. 4 further in detail.
[0062] In one frame having a length of 5 ms shown in Fig. 3, there is a time space for 10
time slots of high-speed data channels for a down-link and an up-link, #71-T0 to #
71-T3, #71-T7A, #71-T7B and # 71-T7C, and# 71-R0 to # 71-R2, and in Fig. 9, the constitution
of one time slot, # 71-T2 for high-speed data is shown out of the ones shown in the
above. The length in time of the high-speed data time slot is 625 µsec and the data
rate (bit rate) is 12.288 Mb/s. Therefore, a number of bits in a high-speed data time
slot is 625 µs x 12.288 Mb/s = 7680 bits = 240 x 32 bits. Thereby, it is understood
that a high-speed data time slot is composed of 32 micro time slots of 240 bits connected
in series. A micro time slot constituted with 240 bits has the same constitution as
that of 1 time slot of a low-speed TDMA data channel. As shown in the above, a high-speed
TDMA data channel is composed of 32 micro time slots, # 91-0 to # 91-31, and each
of them has the same constitution as that of one time slot in a low-speed TDMA data
channel and is composed of a control word 92 of 32 bits, a sync word 93 of 32 bits,
information data 94 of 160 bits and a correction code 95 (CRC) of 16 bits.
[0063] In the constitution of a micro time slot in a high-speed TDMA data channel shown
in Fig. 9, micro time slots, # 91-30 and #91-31, are shown by broken lines, which
shows that these two micro time slots, # 91-30 and # 91-31, make a guard time in a
high-speed TDMA data channel. The guard time is set in proportion to the moving speed
of a user, and in the case of movement in the order of a walking speed, 2 micro time
slots are good enough. For a user who moves by car, about 5 micro time slots are needed.
[0064] The arrangement to vary the length of a guard time corresponding to the moving speed
of a user, and to store the data of the guard time in a memory or the like in the
mobile switching center 6 or 7, as user's data, and to vary the frame constitution
according to the user's data, is effective from the point of view of transmission
efficiency.
[0065] In the above description, it is shown that the constitution of a high-speed TDMA
data channel is composed of a plurality of channels of a low-speed TDMA data channel
connected in series, and it is also good to constitute the high-speed TDMA data channel
with a plurality of channels of a time divided CDMA channel for low-speed data transmission
connected in series.
[0066] A synch word 93 in the schematic drawing of a micro time slot (240 bits) shown in
Fig. 9 is a training sequence of equalizers to remove delay transmission distortion
caused by a plurality of transmission paths. The sync word 93 is provided once for
240 bits, so that in a high-speed TDMA data channel training is executed 30 times.
A high-speed TDMA data channel shown in Fig. 9 as an example is equivalent to 32 low-speed
TDMA data channels connected in series, so that a high-speed equalizer for a high-speed
TDMA data channel is the same as a low-speed equalizer for a low-speed TDMA data channel
except the operation speed of 32 times quick, and this fact also shows that the embodiment
4 is effective.
[0067] The management of the constitution of a micro time slot is performed by the mobile
switching center 6 or 7. and an instruction of change concerning the constitution
of a micro time slot including the length of guard time is given from the mobile switching
center 6 or 7, to at least one base station 1, 3 or 2.
[0068] As mentioned in the above, according to the embodiment 4, a high-speed TDMA data
channel is constituted with a plurality of low-speed TDMA data channels or time divided
CDMA channels for low-speed data transmission connected in series, so that they have
the same constitution except the system low-speed processing unit and the speed. Thereby,
there is an effect that the whole constitution is simplified, which decreases the
costs of design and equipment.
[0069] It is made possible to increase or decrease a guard time in the unit of a micro time
slot, therefore, there is a merit that a proper guard time may be set for a high-speed
moving body, a low-speed moving body or a semi-fixed moving body, which prevents interference
from another channel and at the same time prevents lowered efficiency.
Embodiment 5
[0070] In the following the constitution of a mobile station and a base station to realize
an asymmetric channel including the data transmission by a low-speed TDMA channel,
a time divided CDMA channel, and a high-speed TDMA channel will be explained as an
embodiment 5 according to the present invention.
[0071] Fig. 10 shows a block diagram showing the constitution of a mobile station in the
embodiment 5 according to the present invention. In the drawing, a reference numeral
101 denotes an antenna, 102 denotes a transmission/reception distributor unit which
performs distribution of signals received by the antenna 101 and signals to be transmitted
from the antenna 101, 103 denotes an RF (radio frequency) receiving unit which amplifies
a signal received by the antenna 101, and 104 denotes an RF transmitting unit which
amplifies a signal to be transmitted from the antenna 101. The RF receiving unit 103
comprises a built-in switch for selecting a transmission system, that is, for selecting
a communication system which is able to transmit a necessary quantity of information
in synchronizing with time slots, and the output is changed over corresponding to
a selected communication system.
[0072] A reference numeral 105 denotes a demodulator which comprises high-speed and low-speed
equalizers to remove delay transmission distortion caused by transmission channels,
and demodulates a signal which is selected and output by the RF receiving unit 103
in a case where a low-speed TDMA channel or a high-speed TDMA channel is utilized.
A reference numeral 106 denotes a correlative reception/despread-spectrum encoder
operating unit which multiplies a signal selected and output by the RF receiving unit
103 and a spread-spectrum code assigned to the own station (despread-spectrum decoding
operation) and extracts the original signal which is not subjected to spread-spectrum
encoding (correlating reception) and outputs the signal to the demodulator 105. A
reference numeral 107 denotes a channel reception/TDMA separator unit (hereinafter
referred to as CH reception/TDMA separator unit) which extracts a necessary signal
from the format of a demodulated signal by the demodulator 105 (multiple separation)
and supplies the signal to the processing unit of the signal.
[0073] A reference numeral 108 denotes an error corrector/decoder unit which corrects an
error or errors in the information supplied from the CH reception/TDMA demodulator
unit 107, and decodes high-speed data or a voice-frequency signal extracted from the
information and supplies them to a man-machine interface which is not shown in a drawing.
A reference numeral 109 denotes an error corrector/voice frequency signal encoder
unit which encodes high-speed data or a voice frequency signal supplied from the man-machine
interface, and add a code for error correction to it. A reference numeral 110 denotes
a control information processor which decodes the control data separated in the CH
reception/TDMA separator unit 107, and instructs various functions based on the decoded
data to a mobile station concerned and creates control data of response for them.
[0074] A reference numeral 111 denotes a channel transmission/TDMA multiplexing unit (hereinafter
referred to as CH transmission/TDMA multiplexing unit) which multiplexes high-speed
data or a voice frequency signal encoded with an error correction code and a control
data from the control information processor 110, and incorporates the multiplexed
information into a necessary time slot in a frame format and outputs it. The CH transmission/TDMA
multiplexing unit 111 comprises a built-in switch for selecting a system for transmission,
that is, for selecting a communication system which is able to transmit a necessary
information quantity in synchronizing with time slots, and the output of the switch
is changed over corresponding to a communication system. A reference numeral 112 denotes
a modulator which modulates the information output from the CH transmission/TDMA multiplexing
unit 111 and outputs it to the RF transmitting unit 104 in a case where a low-speed
TDMA channel or a high-speed TDMA channel is utilized. A reference numeral 113 denotes
a correlative encoder/spread-spectrum encoder operating unit, and when a time-divided
CDMA channel is utilized, it spectrum-spreads and encodes the information output from
the CH transmission/TDMA multiplexing unit 111 on the frequency axis utilizing a spread-spectrum
code assigned to the own station, and outputs the encoded information to the modulator
112.
[0075] A reference numeral 114 denotes a burst control/in-frame time setting/time measurement
unit which performs the control of radiation time of a radio burst radiated from the
own station, time setting in a frame for setting a time slot in which a radio wave
is to be radiated, and time measurement for setting transmission timing of the radio
burst. A reference numeral 115 denotes a spread-spectrum code generator/chip rate
generator which generates chip rate to be used for time measurement in the burst control/time
setting in a frame and time measurement unit 114, and a spread-spectrum code assigned
to the own station.
[0076] Next, the explanation concerning the operation of a mobile station constituted as
mentioned in the above.
[0077] A mobile station shown in Fig. 10 realizes an asymmetric channel, and a case will
be herein considered where a high-speed TDMA data channel for transmitting a large
quantity of information data is set for a down-link and a time-divided CDMA channel
as transmitting a small quantity of data is set as an up-link.
[0078] A radio wave carrying a high-speed TDMA data channel radiated from a base station
is received with the antenna 101, and the received signal is input to the RF receiving
unit through the transmission/reception distributor unit 102. Since the received signal
is transmitted through the high-speed TDMA data channel, the signal is directly sent
to the demodulator 105 having equalizers by the function of the built-in switch. The
demodulator 105 demodulates the signal from the RF receiving unit and outputs a digital
signal. The digital signal demodulated in the demodulator 105 is input to the CH-reception/TDMA
separator unit 107, and separated into high-speed data information and control data.
The separated control signal is sent to the control information processor 110 and
the high-speed data information is sent to the error-corrector/demodulator unit 108.
In the error-corrector/demodulator unit 108, after the correction of an error or errors
in the high-speed data information, the data are decoded and transferred to the man-machine
interface.
[0079] The low-speed data from the man-machine interface unit are digitized in the error-corrector/encoder
unit 109, and the data are sent to the CH-reception/TDMA multiplexing unit 111 being
added with an error-correction code. The CH-reception/TDMA multiplexing unit 111 multiplexes
the low-speed data information from the error-corrector/encoder unit 109 and the control
data from the control information processor 110, and incorporates them into a predetermined
time slot, and the incorporated data are output according to the control by the burst-control/time
setting in a frame and time measurement unit 114. When low-speed data information
is transmitted through a time-divided CDMA channel, the multiplexed signal in the
CH-transmission/TDMA multiplexing unit 111 is output to the correlative encoder/spread-spectrum
encoder operating unit 113 by the switching of the built-in switch. In the correlative
encoder/spread-spectrum encoder operating unit 113, the multiplexed signal from the
CH-transmission/TDMA multiplexing unit 111 is CDMA-encoded and after that the signal
is sent to the modulator 112 to be modulated. The signal modulated in the modulator
112 is sent to the antenna 101 through the RF transmitting unit 104 and the transmission/reception
distributor unit 102, and then it is transmitted to the base station.
[0080] Next, a case will be considered where a time-divided CDMA channel for transmitting
low-speed data is set for a down-link and a high-speed TDMA data channel for transmitting
data of a large information quantity is set for an up-link.
[0081] A radio signal in the time-divided CDMA data channel received by the antenna 101
is sent to the RF receiving unit 103 through the transmission/reception distributor
unit 102 and input to the correlative reception/despread-spectrum encoder operating
unit 106 by the selection of the built-in switch in the RF receiving unit 103 and
received correlatively. The output of the correlative reception/despread-spectrum
encoder operating unit 106 is converted into a digital signal by the demodulator 105
having equalizers, and it is separated into low-speed data information and control
data by the CH-reception/TDMA separator unit 107. The control data are sent to the
control information processor 110, and the low-speed data information is sent to the
error corrector/decoder unit 108. The error corrector/decoder unit 108 corrects an
error or errors in the low-speed data information and decodes the data, and transfers
them to the man-machine interface.
[0082] The high-speed data from the man-machine interface unit are encoded in the error
corrector/encoder unit 109, and added with an error correction code, and then the
data are multiplexed with the control data from the control information processor
in the CH-transmission/TDMA multiplexing unit 111. The multiplexed signal is sent
to the modulator 112 by the selection of the built-in switch in the CH-traasmission/TDMA
multiplexing unit 111, and the signal is modulated in the modulator 112, and sent
to the antenna 101 through the RF transmitting unit 104 and transmission/reception
distributor unit 102, and then the signal is transmitted from the antenna 101 to the
base station.
[0083] A mobile station shown in Fig. 10 is able to correspond to a plurality of symmetric
communication channels, such as the cases where both down-link and up-link are assigned
a high-speed data channel, both down-link and up-link are assigned a low-speed TDMA
data channel, both down-link and up-link are assigned a low-speed time-divided CDMA
data channel, however, the explanation concerning the above will be omitted.
[0084] Fig. 11 shows a block diagram showing the constitution of a base station in the embodiment
5 according to the present invention. In the drawing, reference numerals 121 and 122,
denote signal processing units which comprise an equivalent function with the mobile
station shown in Fig. 10 eliminating the antenna 101, transmission/reception distributor
unit 102, RF receiving unit 103, and RF transmitting unit 104.
[0085] Reference numerals 123 and 124, denote adders which make addition of signals output
from a plurality of signal processing units including the above-mentioned signal processing
units 121 and 122. A reference numeral 125 denotes an RF transmitting unit, 126 denotes
an RF receiving unit, 127 denotes a transmission/reception distributor unit, and 128
denotes an antenna.
[0086] In the signal processing units 121 and 122, a reference numeral 130 denotes an error-corrector/encoder
unit, 131 denotes a CH-transmission/TDMA multiplexing unit, 132 denotes a modulator,
133 denotes a correlative encoder/spread-spectrum encoder operating unit, 134 denotes
a burst control/in-frame time setting/time measurement unit, 135 denotes a spread-spectrum
code generator and chip rate generator, 136 denotes a demodulator, 137 denotes a correlative
reception/despread-spectrum decoder operating unit, 138 denotes a CH-reception/TDMA
separator unit, and 139 denotes an error corrector/decoder unit, and these are equivalent
to corresponding parts shown in Fig. 10.
[0087] Next, the operation of a base station constituted as mentioned in the above will
be explained in the following.
[0088] A base station shown in Fig. 11 is able to correspond to both asymmetric communication
channel or symmetric communication channel, and the operation of the signal processing
units 121 and 122, is the same as that of the mobile station shown in Fig. 10. However,
the output signal of a modulator 132 is an intermediate frequency (IF) signal modulated
by an information signal. Therefore, the center frequencies of output signals of respective
modulators 132 or the band width of modulated signals in the signal processing units
121 and 122, and further the constitution of a time slot in a frame are extremely
diverse as shown in Fig. 2 or Fig. 3.
[0089] A signal output from the modulator 132 in the signal processing units 121 and 122
is added to a signal output from the other signal processing unit and supplied to
the RF transmitting unit 125 and further sent to the antenna 128 through the transmission/reception
distributor unit 127 and transmitted from the antenna. The signal received with the
antenna 128 is sent to the RF receiving unit 126 through the transmission/reception
distributor unit 127, and the signal from the RF receiving unit 126 is input to the
demodulator 136 or to the correlative reception/despread-spectrum encoder operating
unit 137.
[0090] In the signal processing units 121 and 122, the exchange of information signals is
performed with a mobile switching center (MSC01) 6, not with the man-machine interface.
Fig. 12 shows a block diagram showing the outline of an interface unit of the base
station to be connected to the mobile switching center 6.
[0091] In the drawing, a reference numeral 140 denotes a memory for converting a time-divided
CDMA channel, 141 denotes a memory for converting a low-speed TDMA data channel, 142
denotes a memory for converting a high-speed TDMA data channel, and 143 denotes a
memory for converting a TDMA/time-divided CDMA control channel. A reference numeral
144 denotes a switch which selects a memory out of the memories 140 to 143, for channel
assignment and connects it to the input of the signal processing unit 121, and also
selects a transmission system, that is, a communication system which is able to transmit
necessary information quantity in synchronization with time slots. A reference numeral
145 denotes a memory for converting a time-divided CDMA channel, 146 denotes a memory
for converting a low-speed TDMA data channel, 147 denotes a memory for converting
a high-speed TDMA data channel, 148 denotes a memory for converting a TDMA/time-divided
CDMA control channel, and 149 denotes a communication system selection switch which
connects a memory selected out of the memories 144 to 148, to the information input
of the signal processing unit 121.
[0092] A reference numeral 150 denotes a memory for converting a time-divided CDMA channel,
151 denotes a memory for converting a low-speed TDMA data channel, 152 denotes a memory
for converting a high-speed TDMA data channel, 153 denotes a memory for converting
a TDMA/time-divided CDMA control channel, and 154 denotes a switch for communication
system selection which selects a memory out of memories 150 to 153, and connects it
to the information input of the signal processing unit 122. A reference numeral 155
denotes a memory for converting a time-divided CDMA channel, 156 denotes a memory
for converting a low-speed TDMA data channel, 157 denotes a memory for converting
a high-speed TDMA data channel, 158 denotes a memory for converting a TDMA/time-divided
CDMA control channel, and 159 denotes a switch for communication system selection
which selects a memory out of memories 154 to 158, and connects it to the information
input of the signal processing unit 122. The direction of channel conversion by the
memories 140 to 143, and 150 to 153, is in an opposite direction to that of channel
conversion by the memories 145 to 148, and 154 to 158.
[0093] The other parts are denoted with the same reference numerals as corresponding parts
shown in Fig. 11, so that their explanation is omitted.
[0094] In Fig. 12, four switches for communication system selection 144, 149, 154 and 159
are shown, and Fig. 13 shows an illustrative drawing showing the assignment of time
slots to these switches 144, 149, 154, and 159 for communication selection in the
form of a table. In the following, the actions of these switches will be explained
referring to Fig. 13.
[0095] The switch 144 is able to select three kinds of communication systems and a control
channel. According to the selection timing of the switch 144 shown in Fig. 13, in
the transmitting time slot T
0 shown in Fig. 3, the switch 144 selects 4T, that is, a control channel # 62-T0 of
the TDMA system. Therefore, during the transmitting time slot T
0 the memory 143 is connected to the information input of the signal processing unit
121 and a control channel is connected to the output of the signal processing unit
121.
[0096] In the transmitting time slot T
1 shown in Fig. 3, the switch 144 selects 1T, that is, time-divided CDMA channel #
61-T1, and during the transmitting slot T
1 the memory 140 is connected to the information input of the signal processing unit
121. Therefore, a speech channel in the time divided CDMA channel is subjected to
frequency spread-spectrum by a spread-spectrum code which is characteristic of the
speech channel, in the signal processing unit 121, and it is output being encoded
with orthogonal coding. In the same way, in the transmitting time slots, T
2 and T
3, the high-speed TDMA data channel # 71-T2 and # 71-T3 are selected.
[0097] According to the timing selection of the switch 149 shown in Fig. 13, in the receiving
time slot R
0 shown in Fig. 3, 4R, that is, a control channel # 62-R0 of the TDMA system is selected
by the switch 149. Therefore, during the receiving time slot R
0 the memory 148 is connected to the information output of the signal processing unit
121, and control information transmitted from the mobile station to the base station
is output to the mobile switching center 6 on the side of the network from the signal
processing unit 121. In the receiving time slot R
1, the switch 149 selects 1R, that is, time divided CDMA channel # 61-R1, and the memory
145 is connected to the information input of the signal processing unit 121. Therefore,
a speech channel signal in the time divided CDMA channel transmitted from the mobile
station to the base station is correlatively detected with a spread-spectrum code
characteristic of the speech channel, thereby, spectrum-despread information is output
to the network side.
[0098] In the same way, in the receiving time slot R
2, time-divided CDMA channel # 61-R2 is selected, and a signal from a mobile station
is correlatively detected with a spread-spectrum code, characteristic of the speech
channel, in the signal processing unit 121, thereby, the spectrum-despread information
is output to the mobile switching center 6 on the side of the network. The speech
channel is a time-divided CDMA channel for low-speed data transmission, however, the
down-link corresponding to the above-mentioned channel is assigned a high-speed TDMA
channel (A speech channel # 71-T2 in the transmitting time slot T
2 shown in Fig. 3 corresponds to this high-speed TDMA channel), which shows that the
up-link and the down-link are not symmetric.
[0099] In the transmitting slot T
7 shown in Fig. 3, 3T, that is, a high-speed TDMA data channel # 71-T7A is selected
by the switch 144. Further, the predetermined transmitting time slot T
3 is in the down-link and is # 71-T3 which handles a high-speed TDMA data channel,
and 2 down-links comprise the same transmission rate, and 2 channels in the CDMA #
61-R1 are corresponding channels in the up-link.
[0100] The operations of switches 154 and 159, are the same as those of switches 144 and
149, so that their explanation will be omitted.
[0101] The management of communication channel assignment is performed by the mobile switching
centers, 6 and 7, and the instruction of channel assignment is given by the mobile
switching center 6 or 7, to at least one base station 1, 3 or 2.
[0102] As mentioned in the above, according to the embodiment 5, a base station and a mobile
station are respectively provided with switches which select communication systems
in synchronization with time slots, so that by assigning channels having different
communication systems from each other to a down-link and an up-link, an asymmetric
channel may be realized. Thereby, there is an effect that both asymmetry in transmitting
communication capacity and asymmetry in time are realized, which is needed in the
circumstances such as multimedia.
Embodiment 6
[0103] Next, the management of mobile station information concerning services which mobile
stations may be able to enjoy will be explained in the following as an embodiment
6 according to the present invention.
[0104] Fig. 14 shows a block diagram showing the constitution of a mobile switching center
having the management function of mobile station information as mentioned in the above.
In the drawing, a reference numeral 6 denotes a mobile switching center (MSC01) which
is shown in Fig. 1 with the same reference numeral, 1 and 3 denote base stations (BS1
and BS3) being connected to the mobile switching center 6, 8 denotes a public switching
telephone network (PSTN) in which the mobile switching center 6 is accommodated. A
reference numeral 160 is a database of a mobile communication system being connected
to a public switching telephone network 8, and the database stores the mobile station
information of all mobile stations in the mobile communication system concerning the
services and so on which will be enjoyed by all of them.
[0105] In the mobile switching center 6, 170 denotes a PSTN interface which performs transmission/reception
of information including signaling signals, such as dial signals, information of communication
charges, and information of private personal codes, and so on, 171 denotes a speech
path exchange unit which transmits the information obtained from a public switching
telephone network to a base station related to a mobile station, a receiving terminal,
and transmits the information obtained from the mobile station through the base station
to the public switching telephone network 8. A reference numeral 172 denotes a system
setting processor which selects a radio system to connect a base station and a mobile
station and instructs to set the selected radio system between the base station and
the mobile station, and 173 denotes a signaling processor which processes the number
of a mobile station to be connected or private code procedures for collecting charges.
A reference numeral 174 denotes a base station interface which communicates with respective
base stations concerning the information to be transmitted to mobile stations through
base stations, signaling information with mobile stations, system information which
stipulates radio connection, and so on. A reference numeral 175 denotes a mobile station
information memory which is provided in a mobile station belonging to the mobile switching
center 6 or in a cell of a base station being controlled presently by the mobile switching
center 6, and the mobile station information concerning mobile stations being connected
to these base stations is registered in the mobile station information memory.
[0106] Fig. 15 shows an illustrative drawing showing an example of mobile station information
registered in the mobile station information memory 175. The management of mobile
station information will be explained referring to Fig. 15.
[0107] In the example shown in Fig. 15, a mobile station (multimedia station 5) having a
subscriber's number of DS51-727 is able to set 3 kinds of communication channels except
a control channel between the own station (multimedia station 51) and a base station.
In multimedia circumstances, both mobile station and base station are able to perform
communication in freely switching over these 3 kinds of communication channels, a
TDMA voice frequency/low-speed data channel, a time-divided CDMA voice frequency/low-speed
data channel, and a high-speed TDMA data channel (transmission/reception) according
to the speed of information to be transmitted. Moreover, in this mobile communication
system, these 3 kinds of communication channels may be arbitrarily selected for an
up-link or a down-link, and further, the transmission speed of communication information
may be changed as occasion demands.
[0108] In the mobile station having a subscriber's number of MS32-728 (ordinary mobile station
32) comprises only 2 kinds of communication channels except a control channel. The
ordinary mobile station 23 is a mobile terminal of a conventional type which does
not require transmission of a large information quantity of data such as image data,
so that it does not comprise a high-speed data transmission channel. In other words,
the mobile station comprises only a TDMA voice frequency/low-speed data channel and
a time-divided CDMA voice frequency/low-speed data channel, but no high-speed TDMA
data channel.
[0109] In the case where a high-speed TDMA data communication function is assigned, a mobile
station having only the function of reception and that having the function of both
transmission and reception are discriminated from each other. For example, a mobile
station having a subscriber's number of DS51-727 (multimedia station) and a mobile
station having a subscriber's number of WS42-727 (WLL station 42) are mobile stations
having a function of both transmission and reception, and a mobile station having
a subscriber's number of DS52-728 (multimedia station 52) comprises only a receiving
function concerning high-speed TDMA data communication.
[0110] The mobile information as shown in Fig. 15 is transmitted from a database 160 of
the mobile communication system shown in Fig. 14 to the mobile switching center 6.
In the database 160 of the mobile communication system, mobile station information
of all motile stations is stored, however, to the mobile switching center 6 only the
mobile station information concerning the mobile stations related to the mobile switching
center 6 is transmitted and the information is stored in the mobile station information
memory 175 in the mobile switching center 6. The registration of the mobile switching
center information to the information memory 175 of the mobile switching center is
created by a call or position registration of a mobile station in a cell of the base
station 1 or 3, controlled by the mobile switching center 6, or by an inquiry of the
existence of a mobile station assigned by another mobile switching center.
[0111] In case the mobile switching center 6 assigns communication channels to mobile stations
which belong to the mobile switching center 6 or are in the cells of the base station
1 or 3 and are wirelessly connected to the base stations 1 or 3, it accesses the mobile
station information memory 175 and recognizes the services which may be enjoyed by
the mobile station and assigns channels corresponding to the recognition.
[0112] When a mobile station communicates with a base station using the mobile station information
registered in the mobile station information memory 175 of the mobile switching center
6, the new information in the mobile station information memory 175 concerning the
mobile station is transferred to the public switching telephone network and transferred
to the database 160 of the mobile communication system through the public switching
telephone network. Thus, the contents accumulated in the database of the mobile communication
system are revised.
[0113] As mentioned in the above, according to the embodiment 6, since a mobile station
information memory for registering mobile station information of mobile stations under
the control of the mobile switching center is provided in the mobile switching center,
it makes the mobile switching center know easily the services which may be enjoyed
by mobile stations under the control of the mobile switching center. Thereby, there
is a merit that channel assignment may be effectively executed.
Embodiment 7
[0114] Next, data transmission of a large information quantity with a high-speed data transmission
channel will be explained in the following as an embodiment 7 according to the present
invention.
[0115] Fig. 16 shows a block diagram showing the constitution of a mobile switching center
provided with management function of a high-speed data channel. In the drawing, 1
and 3 denote base stations (BS1 and BS3), 6 denotes a mobile switching center (MSC01),
and 8 denotes a public switching telephone network (PSTN). In the mobile switching
center 6, 170 denotes a PSTN interface, 171 denotes a speech channel exchange unit,
172 denotes a system setting processor, 173 denotes a signaling processor, and 174
denotes a base station interface. These components correspond to those having the
same reference numerals shown in Fig. 14, so that detailed explanation will be omitted.
[0116] A reference numeral 161 shows a system which handles a large information quantity
which is a call originating source of high-speed data requested by a mobile station,
and it may be connected with the mobile switching center 6 through the public switching
telephone network, and here in this place, an environment database and Italian Tourist
Society database are shown as examples. In the following explanation, various kinds
of databases as systems to be call originating sources are simply called databases.
A reference numeral 176 in the mobile switching center 6 denotes a memory device for
high-speed data communication which temporarily stores high-speed data transmitted/received
between a mobile station and the database 161 when a mobile station is connected to
the database 161.
[0117] Next, the function of the above-mentioned memory device for high-speed data communication
176 will be explained. When a mobile station is being connected to the database 161,
a case where a control signal is transmitted from the mobile station to the database
161 will be considered. It is assumed that an instruction of "stop data transmission",
for example, as a control information is transmitted from a mobile station to the
database 161. In such a case, it is supposed that a relatively large quantity of high-speed
data would have been sent out from the database 161 before the command reaches the
database 161 through a base station, 1 or 3, the mobile switching center 6 and a public
switching telephone network 8.
[0118] If the instruction "stop data transmission" is issued in a case where the connection
with the base station is to be cut off when the work in the mobile station is over,
there is no problem. In such a case, the high-speed data which have been transmitted
from the database 161 before the instruction reaches the database 161 may be abandoned
without sending them to the mobile station.
[0119] However, when the instruction "stop data transmission" is issued to give a user a
period of time for consideration, following the instruction "stop data transmission",
when the user's consideration is finished, another instruction "transmit data" may
be issued from the mobile station again to the database 161. In preparation for such
a case, a memory device 176 for high-speed data communication is provided in the mobile
switching center 6 and the high-speed data sent out until the stop of transmission
from the database 101 to the mobile switching center 6 are temporarily stored in the
memory device 176 for the high-speed data communication.
[0120] Fig. 17 shows an illustrative drawing showing minimum necessary related information
for managing the contents of the memory device for high-speed data communication 176
in the form of a table, and the related information includes the following: a database
name to be a call originating source of high-speed data, the oldest time of reception
of information among the residual information received from the database, the mobile
station number to which data are transmitted, the latest time of transmission of data
to a mobile station, the stored information number at the head of the residual information
and the stored information number at the end of the residual information, the quantity
of residual information, a corresponding control system, and so on.
[0121] Fig. 18 shows a flow chart showing a control process of the memory device for high-speed
data communication 176.
[0122] In the following, the data transmission of a large information quantity with a high-speed
transmission channel will be explained referring to Fig. 17 and Fig. 18, in taking
an example of a case where the instruction, "stop data transmission", is issued from
a mobile station during the transmission of high-speed data from the database 161
to the mobile station.
[0123] When an instruction, "data transmission" is issued by a mobile station, at first
in step ST11, the database 161 assigned by the instruction and the mobile switching
center 6 are connected through the public switching telephone network 8 and the mobile
switching center receives necessary high speed data from the database 161. Next, in
step ST12, the mobile switching center 6 transmits the data received from the database
161 to a mobile station using a down-link, from the base station to the mobile station,
with a high-speed TDMA data transmission system.
[0124] Next, in step ST13, the existence of an instruction, "stop data transmission" is
investigated, and if there is not, the process is brought back to step ST12, and as
far as the instruction, "data transmission" exists, the transmission of high-speed
data received from the database 161 is repeated.
[0125] At this time, assuming that an instruction, "stop data transmission" addressed to
the database 161 is transmitted by the mobile station to the mobile switching center
6 through the base station. When the mobile switching center 6 reads the instruction,
the process is advanced to step ST13 and step ST14, and the transmission of high-speed
data to the mobile station is stopped and at the same time an instruction, "stop data
transmission" is issued to the database 161. When the mobile station issues the instruction,
"stop data transmission" , if the high-speed data transmitted from the database 161
are normally received in the mobile station , it transmits the last number of the
received high-speed data as a part of a control signal.
[0126] To be concrete, the last number of the high-speed data which are normally received
is dealt as shown below: a series of time slot numbers are given to respective multi-frames
of the high-speed data, and when the mobile station receives high-speed data normally,
the time slot number of the high-speed data received in the last time is detected
and the time slot number is transmitted as a normal time slot number to the mobile
switching center 6 through the base station being connected to the mobile station.
[0127] On the other hand, in step ST15, in the mobile switching center 6, after the instruction,
"stop data transmission" has been issued, the high-speed data continued to be transmitted
from the database 161 are not abandoned and stored in the memory device for high-speed
data communication 176. In other words, the mobile switching center 6 receives the
normal time slot number which is sent from a mobile station when it receives high-speed
data normally, and the high-speed data having slot numbers on and after the one next
to the normal slot number are not abandoned immediately and they are stored in the
memory device for high-speed data communication 176. When the mobile switching center
6 receives the normal time slot number, the high-speed data having slot numbers on
and before the normal time slot number are erased from the memory device for high-speed
data communication 176.
[0128] Next, in step ST16, it is investigated that the instruction, "data transmission",
which instructs the resumption of data transmission is issued again from the mobile
station to the mobile switching center or not. In the result, if there is, the process
is brought back to step ST12, and the high-speed data having time slot numbers on
and after the one next to the normal slot number received from the mobile station
are read out of the memory device for high-speed data communication 176 and the transmission
of the high-speed data to the mobile station is resumed.
[0129] On the other hand, when there is not re-transmission of the instruction, "data transmission",
the process is advanced to step ST 17, and it is investigated whether the mobile station
has cut off the connection or not. If not, process is brought back to step ST16 and
the existence of re-transmission of the instruction, "data transmission" is investigated.
[0130] In a case where a user finishes his work and cuts off a channel which has been used
in leaving high-speed data in the memory device for high-speed data communication
176, process is advanced to step ST18 from step ST17, and the information quantity
of high-speed data left in the memory device for high-speed data communication 176,
that is, the information quantity of high-speed data having time slot numbers of on
and after the one next to the normal time slot number is informed to the database
161 through the public switching telephone network 8. The data concerning the residual
information quantity sent to the database 161 as mentioned in the above, are the high-speed
data which were sent to the mobile switching center 6 but not to the mobile station,
and the data are used for such a case where the database offerer deducts the rates
for the data not delivered.
[0131] In the mobile switching center 6, when the data received from the database 161 through
the public switching telephone network are stored in the memory device for high-speed
data communication 176, the high-speed data are sectioned in blocks in a way that
each block may be transmitted within a time slot, and every block is assigned a storage
information number so that the mobile switching center is able to control these blocks.
Further, it is also possible to give a function as shown below to a base station which
receives high-speed data from a mobile switching center 6 and transfers the data to
a mobile station: the time slot numbers used when high-speed data are transmitted
to a mobile station are compared with the storage information number added by the
mobile switching center 6, and these two kinds of numbers are incorporated into one
set of information and the information is transmitted to the mobile switching center
6, and the management and control of the memory device for the high-speed data communication
176 is performed based on the information.
[0132] During the period of time in which the mobile switching center 6 is transmitting
the high-speed data stored in the memory device for high-speed data communication
176 to a mobile station through a connected base station, when the information quantity
of high-speed data left in the memory device for high-speed data communication 176
becomes lower than a predetermined level of quantity, the mobile switching center
6 requires the transmission of succeeding data to the database 161 through the public
switching telephone network 8.
[0133] In a case where the high-speed data sent from the mobile switching center 6 through
a connected base station are not received normally by a mobile station, the mobile
station detects the time slot number in the high-speed data and transmits the slot
number as an abnormal time slot number to the mobile switching center 6 through a
connected base station. When the mobile switching center 6 receives the abnormal time
slot number, it reads the high-speed data having the same time slot number as the
abnormal time slot number out of the memory device for high-speed data communication
176 and send them again through the connected base station.
[0134] As mentioned in the above, according to the embodiment 7, the mobile switching center
is provided with a memory device for high-speed data communication for storing the
high-speed data to be transmitted to a mobile station temporarily, so that it is able
to correspond promptly for the transmission request of high-speed data from a user,
and a partial missing in the information of high-speed data may be prevented, and
furthermore, communication rates corresponding to the quantity of information transmitted
to a user may be correctly calculated by notifying the residual information quantity
to the database.
Embodiment 8
[0135] Next, the explanation concerning the management of channels in respective mobile
stations will be given in the following as an embodiment 8 according to the present
invention.
[0136] Fig. 19 shows an illustrative drawing showing an example of a control table of communication
channels in respective mobile stations, and as an example, a control table of communication
channels of respective mobile stations under the control of a base station (BS1).
The mobile switching center and at least one base station being under the control
of the mobile switching center are provided with mobile station control memories respectively,
and the communication channel control table shown in Fig. 19 is stored in the mobile
station control memory.
[0137] According to the example shown in Fig. 19, a mobile station (multimedia station 51)
having a station code of DS51-727 is assigned a high-speed TDMA data channel for the
down-link and a time-divided CDMA low-speed data channel (or a voice frequency channel)
for the up-link. The example shown in this place shows a case where an asymmetric
channel having different links for the down-link and the up-link is assigned to a
mobile station. On the other hand, a mobile station having a station code of WS42-727
(WLL station WS42) is assigned control channels for intermittent connection for both
down-link and up-link, which may indicate that the user of the mobile station is under
consideration.
[0138] As shown in the above-mentioned examples, the mobile communication system is able
to handle both an asymmetric channel and a symmetric channel.
[0139] Including the assignment of a transmission type, it is also possible to assign a
time slot as shown in Fig. 19. For example, in an up-link, a time-divided CDMA voice
frequency/low-speed data channel, of a multimedia station 51 having a station code
of DS51-727, a time slot of #61-R2-07 is assigned. The time slot number is the same
as that shown in Fig. 3. The time slot #61-R2 denotes a time slot positioned at the
second row from the top of the time slot column on the left side in Fig. 3, and the
succeeding code -07 denotes a channel having a spread-spectrum code called the seventh
in the code-division multiple access (CDMA) including a plurality of the time slots.
[0140] In the up-link, "a control information channel for intermittent connection" of WLL
station 42 having a station code WS42-727 a time slot called #61-R3-05:36 is assigned,
and the time slot name is the same as the time slot name shown in Fig. 3. The time
slot #61-R3 denotes a time slot at the highest row of the time slot column on the
left side in Fig. 3. The succeeding code -05 denotes a channel having a spread-spectrum
code called the fifth of code-division multiple access (CDMA) including a plurality
of time slots, and further succeeding code : 36 shows that it is the information included
in the 36th time slot in a multi-frame (be composed of 40 frames).
[0141] In the columns of a transmission type and a time slot name shown in Fig. 19, the
channels of a transmission type with an underline and a time slot name with an underline
show the ones being used at the present point of time. Naturally, a transmission type
in operation may be switched to another momentarily by the requirement of a user or
according to the contents of data from the database being transmitted. Furthermore,
in the present mobile communication system, the up-link and the down-link may be independently
set of each other.
[0142] In Fig. 19, 2 representative examples are shown, however for every subscriber in
the communication system his communication channel may be set as shown in Fig. 19.
[0143] As mentioned in the above, in a case where a mobile switching center operates channels
assigning time slots corresponding to respective transmission types, when the operation
of a channel which is assigned to a time slot corresponding to the present transmission
type is finished, the above time slot assignment is stored in the built-in management
memory for mobile stations as a history. When the same transmission type is assigned,
the mobile switching center assigns a time slot which has been actually used kept
in the history being left in the mobile station control memory and operates the channel
for the above-mentioned transmission type.
[0144] In a case where a time slot name which has a history of actual use in the past is
stored in the mobile station control memory as a time slot not in use, the mobile
switching center erases the history of a time slot having an actual use only when
a time slot name of the same transmission type which does not have the history of
an actual use in the past is not found in the mobile station control memory, and the
erased time slot name is assigned to be used for a new mobile station. The following
method is also possible: when the history of a time slot which has a history of an
actual use in the past is erased, a time slot name which has the oldest history of
an actual use is selected and it is assigned as a time slot to be used for a new mobile
station.
[0145] As mentioned in the above, according to the embodiment 8, owing to the arrangement
in which a communication channel control table is stored in mobile station management
memories provided in a mobile switching center and at least one base station which
is under the control of the mobile switching center, an up-link and a down-link between
a mobile station and a base station may be set with different type of communication
links independently of each other.
Industrial Applicability
[0146] A mobile communication system according to the present invention comprises a FDMA/TDMA
digital communication channel and a time-slot-common-use and frequency-channel-common-use
time-divided CDMA signal channel (common channel) on the frequency axis, wherein a
plurality of mobile stations and a base station are connected with two-way communication
channels such as FDMA/TDD system, multi-carrier TDMA system, CDMA/TDD system, or time-divided
CDMA system using signals modulated by digital modulation system. The present system
is useful when it is applied to a mobile communication system which corresponds to
multimedia circumstances.
1. A mobile communication system, comprising:
a plurality of mobile stations and at least one base station, said mobile stations
and said base station being radio-connected to each other using a multiple access
system being, a combination of TDMA, FDMA and CDMA and the up-link and down-link being
separated in a Time Division Duplex TDD manner,
wherein at least one of said plurality of mobile stations is capable of selecting
between a low speed CDMA data transmission function or a high speed TDMA data transmission
function for radio-connection to said base station, and wherein the communication
channel in said mobile communication system is constituted by an asymmetric channel,
and
the information quantity to be transmitted in either of the uplink or the downlink
is not fixed, and dependent upon system requirements the uplink information quantity
can be greater or less than that in the downlink, and
the choice between a high speed TDMA or a low speed CDMA multiple access scheme in
both the uplink or downlink directions is determined according to the actual information
quantity to be transmitted.
2. A mobile communication system according to claim 1, wherein said system comprises
a mobile switching center having a function to instruct at least one base station
to change an information quantity in an up-link from a mobile station to a base station,
and an information quantity in a down-link from said base station to said mobile station.
3. The mobile communication system of claim 1, further adapted to, when data transmission
of a large information quantity is finished in either or both of up-link and down-link,
immediately switch over to a small quantity data transmission channel.
4. A mobile communication system according to claim 3 adapted to, when a base station
and a mobile station are radio-connected with a small quantity data transmission channel,
and if for a predetermined period of time, data transmission is not executed switch
over to a control channel for connection which transmits only control data.
5. A mobile communication system according to claim 4, further configured such that in
a state where a base station and a mobile station are radio-connected with a control
channel for connection, if there occurs a necessity of data transmission of a large
information quantity in either of an up-link from said mobile station to said base
station, or a down-link from said base station to said mobile station, or both of
them, said control channel for connection may be immediately switched over to a large
quantity data transmission channel.
6. A mobile communication system according to claim 4, further configured such that when
a base station and a mobile station are radio-connected with a control channel for
connection, if a necessity occurs of transmission of data of small information quantity
in either of an up-link from said mobile station to said base station, or a down-link
from said base station to said mobile station, or both of them, said control channel
for connection is immediately switched over to a small quantity data transmission
channel.
7. A mobile communication system according to claim 3, further configured such that when
a base station and a mobile station are radio-connected with a small quantity data
transmission channel, if a necessity occurs of data transmission of a large information
quantity in either of an up-link from said mobile station to said base station, or
a down-link from said base station to said mobile station, or both of them, said small
quantity data transmission channel is immediately switched over to a large capacity
data transmission channel.
8. A mobile communication system according to claim 3, wherein said system comprises
a mobile switching center provided with a function to instruct at least one base station
to perform the management of an asymmetric communication channel and the changeover
of said asymmetric communication channel.
9. The mobile communication system of claim 1, wherein said communication system further
comprises small-capacity data transmission channels utilizing a multi-frame system
which are independent of each other in said up-link and down-link respectively.
10. A mobile communication system according to claim 9, wherein during the period of time
while data are not transmitted between a base station and a mobile station, said small
capacity data transmission channel is a control information channel for intermittent
connection for transmitting control data.
11. A mobile communication system according to claim 10, wherein the control information
channel for intermittent connection transmits, besides ordinary control data, the
control data showing that no data are being transmitted in a period of time from a
transmission of a large information quantity of data from a base station to a mobile
station till an answer for said large quantity of information.
12. A mobile communication system according to claim 10, wherein said mobile communication
system, comprises a mobile switching center which is adapted to perform the management
of a control information channel for intermittent connection and comprises a function
to instruct at least one base station in the starting, switching, and suspension of
said control information channel for intermittent connection.
13. The mobile communication system of claim 1, further wherein a TDMA data channel is
used as a said high-speed data channel and a time slot in said TDMA data channel is
further divided into a series of micro time slots with each of the said micro time
slots comprising the same number of bits as a low-speed TDMA data channel time slot.
14. A mobile communication system according to claim 13, further comprising an equalizer
to be used for a high-speed TDMA data channel being arranged to have the same constitution
as an equalizer to be used in a low-speed TDMA data channel except the operation speed.
15. A mobile communication system according to claim 13, wherein when a high-speed TDMA
data channel is constituted with a plurality of micro time slots, the guard time of
the high-speed TDMA data channel is changed in the unit of a micro time slot according
to the moving speed of a mobile station.
16. A mobile communication system according to claim 13, wherein said system comprises
a mobile switching center which is configured to manage the constitution of a micro
time slot in a high-speed TDMA data channel and is provided with a function to instruct
at least one base station to change the constitution of a micro time slot including
the length of a guard time of said high-speed TDMA data channel.
17. The mobile communication system of claim 1, further wherein said base station and
said mobile station are provided with switches respectively for selecting a communication
system which is able to transmit a necessary information quantity in synchronisation
with time slots.
18. A mobile communication system according to claim 17, wherein a base station comprises
a memory for channel assignment which enables to set a down-link and an up-link to
and from a mobile station in a communication channel to be independent of each other,
said communication channel being constituted with a combination of a frequency and
a time slot.
19. A mobile communication system according to claim 17, wherein said mobile communication
system comprises a mobile switching center which is adapted to control channel assignment
and is provided with a function to instruct a base station in the assignment of communication
channels.
20. The mobile communication system of claim 1, further wherein a mobile switching centre,
being connected to said mobile stations, is provided with a mobile station information
memory for storing mobile information including the information showing the services
to be enjoyed by said mobile stations which are under the control of said mobile switching
centre.
21. A mobile communication system according to claim 20, wherein a mobile switching center
is adapted to perform the management of mobile station information concerning mobile
stations being under the control of said mobile switching center and comprises a function
to instruct at least one base station in the starting, switching and suspension of
services based on said mobile station information.
22. A mobile communication system according to claim 20, wherein a mobile switching center
is adapted to perform the management of the mobile station information concerning
the mobile stations being under the control of said mobile switching center, and in
a case that an amendment occurs in said mobile station information, said mobile switching
center is provided with a function to transfer the amended mobile station information
to the database of said mobile communication system which contains the mobile station
information concerning all mobile stations in said mobile communication system.
23. The mobile communication system of claim 1, further wherein a mobile switching centre
being connected to said base station is provided with a memory device for high-speed
data communication to temporarily store the high-speed data transmitted to said mobile
stations.
24. A mobile communication system according to claim 23, wherein when the high-speed data
transmitted from a mobile switching center through a connected base station are normally
received in a mobile station,
said mobile station is adapted to detect a time slot number of the last high-speed
data and is further adapted to transfer the slot number as a normal slot number to
said mobile switching center through said base station.
25. A mobile communication system according to claim 24, wherein a mobile switching center
is adapted to perform the management of high-speed data to be transmitted to a mobile
station and is further adapted to receive said normal time slot number transmitted
from said mobile station which has received said high-speed data, and is further adapted
to store high-speed data having slot numbers on and after the slot number next to
the normal slot number in the memory device for high-speed communication.
26. A mobile communication system according to claim 25, wherein a mobile switching center
is adapted to perform the management of high-speed data to be transmitted to a mobile
station, and when there is a request from said mobile station to said mobile switching
center to transmit said high-speed data again, said switching center is further adapted
to read the high-speed data having time slot numbers on and after the time slot number
next to the normal time slot number out of the memory device for high-speed data communication
and transmit the high-speed data to said mobile station through the base station.
27. A mobile communication system according to claim 23, wherein when a mobile switching
center is adapted to receive the high-speed data to be transmitted to a mobile station
from the call originating source of the high-speed data through a public switching
telephone network in which said mobile switching center is accommodated and is further
adapted to store the data in said memory device for high-speed communication, the
high-speed data are sectioned into blocks of data so that each block of data may be
transmitted in a time slot, and each block is numbered with a storage information
number for management.
28. A mobile communication system according to claim 27, wherein a base station which
transmitted high-speed data to a mobile station is adapted to contrast the time slot
number of the transmitted high-speed data to the storage information number numbered
by the mobile switching center to which the base station is connected, and is further
adapted to incorporate said time slot number and said storage information number into
a set of information and is further adapted to notify the information to said mobile
switching center.
29. A mobile communication system according to claim 24, wherein a mobile switching center
is adapted to perform the management of the high-speed data to be transmitted to mobile
stations and is provided with a function to erase the high-speed data having time
slot numbers on and before the normal time slot number from the memory device in which
the high-speed data are stored.
30. A mobile communication system according to claim 24, wherein a mobile switching center
is adapted to perform the management of the high-speed data to be transmitted to mobile
stations and is provided with functions such that when a mobile station finishes communication,
the information quantity of high-speed data left in the memory device for high-speed
data communication having time slot numbers on and after the time slot number next
to the normal time slot number transmitted from said mobile station through the base
station is notified to the call originating source of said high-speed data.
31. A mobile communication system according to claim 26, wherein a mobile switching center
is adapted to perform the management of the high-speed data to be transmitted to mobile
stations and the mobile switching center is provided with a function such that when
said high-speed data requested by said mobile station are being transmitted to a base
station, at the point of time when the information quantity of said high-speed data
left in the memory device for high-speed data communication reaches a level lower
than a predetermined level, the mobile switching center is further adapted to request
the transmission of the succeeding high-speed data for the call originating source
of the high-speed data through the public switching telephone network.
32. A mobile communication system according to claim 23, wherein when high-speed data
transmitted from a mobile switching center through connected base station are not
received normally by a mobile station, the mobile station is adapted to detect the
time slot number of the transmitted high-speed data and transmit the number as an
abnormal time slot number to said mobile switching center through the connected base
station.
33. A mobile communication system according to claim 32, wherein a mobile switching center
is adapted to perform the management of the high-speed data to be transmitted to mobile
stations, and when said high-speed data are not received normally in a mobile station,
the mobile switching center, at the reception of the abnormal time slot number, is
adapted to read the high-speed data having the same time slot number as the abnormal
time slot number out of the memory device for high-speed data communication, and transmit
the high-speed data again to said mobile station.
34. The mobile communication system of claim 1, further wherein said mobile switching
centre connected to said base station is provided with a mobile station management
memory for storing a communication channel management table to be used for the management
of communication channels connecting said mobile switching centre and respective mobile
stations, and
wherein said mobile switching centre is adapted to assign a time slot corresponding
to the transmission type and after the operation of assignment of the time slot corresponding
to the current transmission type is finished, the assigning operation of the time
slot is stored in said mobile station management memory as a history, and in a case
that the same transmission type is requested again, the time slot having an actual
use in the past existing in the history in said mobile station management memory is
used.
35. A mobile communication system according to claim 34, further configured such that
when the name of a time slot which has a history of actual use in the past is stored
in a mobile station management memory as a time slot presently being not used, only
when a time slot name which does not have a history of actual use in the past of the
same kind of transmission type is not found in said mobile station management memory,
the history of the time slot name which has the history of actual use in the past
is erased from said mobile station management memory and it is assigned to a new mobile
station.
36. A mobile communication system according to claim 35, further configured such that
when the name of a time slot which has a history of actual use in the past is stored
in a mobile station management memory as a time slot not being used presently, when
a time slot name which does not have a history of actual use in the past of the same
kind of transmission type is not found in said mobile station management memory and
the history of the time slot name which has the history of actual use in the past
is erased from said mobile station management memory, a time slot which has the oldest
history of actual use in the past is selected and it is assigned to a new mobile station.
1. Mobilkommunikationssystem, das Folgendes aufweist:
eine Vielzahl von Mobilstationen und mindestens eine Basisstation, wobei die Mobilstationen
und die Basisstation in Funkverbindung miteinander sind unter Verwendung eines Vielfachzugriffsystems,
das eine Kombination aus TDMA, FDMA und CDMA ist, und wobei der Uplink und der Downlink
mittels eines Zeitgetrenntlageverfahren (TDD) getrennt sind,
wobei mindestens eine der Vielzahl von Mobilstationen imstande ist, zwischen einer
langsamen CDMA-Datenübertragungsfunktion oder einer schnellen TDMA-Datenübertragungsfunktion
zur Funkverbindung mit der Basisstation zu wählen, und wobei der Übertragungskanal
in dem Mobilkommunikationssystem von einem asymmetrischen Kanal gebildet ist, und
die entweder in dem Uplink oder dem Downlink zu übertragende Informationsmenge nicht
festgelegt ist und in Abhängigkeit von Systemerfordernissen die Uplink-Informatiönsmenge
größer oder kleiner als die in dem Downlink sein kann, und
die Wahl zwischen einem schnellen TDMA- oder einem langsamen CDMA-Vielfachzugriffschema
sowohl in der Uplink- oder der Downlink-Richtung in Abhängigkeit von der zu übertragenden
tatsächlichen Informationsmenge bestimmt wird.
2. Mobilkommunikationssystem nach Anspruch 1, wobei das System eine Funkvermittlungsstelle
aufweist, die eine Funktion hat, mindestens eine Basisstation anzuweisen, eine Informationsmenge
in einem Uplink von einer Mobilstation zu einer Basisstation zu ändern und eine Informationsmenge
in einem Downlink von der Basisstation zu der Mobilstation zu ändern.
3. Mobilkommunikationssystem nach Anspruch 1, das ferner dazu angepasst ist, dann, wenn
die Datenübertragung einer großen Informationsmenge in einer oder beiden von dem Uplink
und dem Downlink beendet ist, sofort zu einem Übertragungskanal für eine kleine Datenmenge
umzuschalten.
4. Mobilkotnmunikationssystem nach Anspruch 3, das dazu angepasst ist, dann, wenn eine
Basisstation und eine Mobilstation mit einem Übertragungskanal für eine kleine Datenmenge
in Funkverbindung sind und wenn für einen vorbestimmten Zeitraum keine Datenübertragung
ausgeführt wird, zu einem Steuerkanal zur Verbindung umzuschalten, der nur Steuerdaten
überträgt.
5. Mobilkommunikationssystem nach Anspruch 4, das ferner so ausgebildet ist, dass in
einem Zustand, in dem eine Basisstation und eine Mobilstation mit einem Steuerkanal
zur Verbindung in Funkverbindung sind, wenn eine Notwendigkeit zur Datenübertragung
einer großen Informationsmenge entweder in einem Uplink von der Mobilstation zu der
Basisstation oder in einem Downlink von der Basisstation zu der Mobilstation oder
in beiden auftritt, der Steuerkanal zur Verbindung sofort zu einem Übertragungskanal
für eine große Datenmenge umgeschaltet werden kann.
6. Mobilkommunikationssystem nach Anspruch 4, das ferner so ausgebildet ist, dass dann,
wenn eine Basisstation und eine Mobilstation mit einem Steuerkanal zur Verbindung
in Funkverbindung sind, wenn eine Notwendigkeit zur Datenübertragung einer kleinen
Informationsmenge entweder in einem Uplink von der Mobilstation zu der Basisstation
oder in einem Downlink von der Basisstation zu der Mobilstation oder in beiden auftritt,
der Steuerkanal zur Verbindung sofort zu einem Übertragungskanal für eine kleine Datenmenge
umgeschaltet wird.
7. Mobilkommunikationssystem nach Anspruch 3, das ferner so ausgebildet ist, dass dann,
wenn eine Basisstation und eine Mobilstation mit einem Übertragungskanal für eine
kleine Datenmenge in Funkverbindung sind, wenn eine Notwendigkeit zur Datenübertragung
einer großen Informationsmenge entweder in einem Uplink von der Mobilstation zu der
Basisstation oder in einem Downlink von der Basisstation zu der Mobilstation oder
in beiden auftritt, der Übertragungskanal für eine kleine Datenmenge sofort zu einem
Datenübertragungskanal großer Kapazität umgeschaltet wird.
8. Mobilkommunikationssystem nach Anspruch 3, wobei das System eine Funkvermittlungsstelle
aufweist, die mit einer Funktion versehen ist, mindestens eine Basisstation anzuweisen,
das Management eines asymmetrischen Übertragungskanals und die Umschaltung des asymmetrischen
Übertragungskanals auszuführen.
9. Mobilkommunikationssystem nach Anspruch 1, wobei das Kommunikationssystem ferner ein
Mehrfachdatenübertragungsblocksystem verwendende Datenübertragungskanäle kleiner Kapazität
aufweist, die in dem Uplink bzw. dem Downlink unabhängig voneinander sind.
10. Mobilkommunikationssystem nach Anspruch 9, wobei während des Zeitraums, in dem keine
Daten zwischen einer Basisstation und einer Mobilstation übertragen werden, der Datenübertragungskanal
kleiner Kapazität ein Steuerinformationskanal zur intermittierenden Verbindung zum
Übertragen von Steuerdaten ist.
11. Mobilkommunikationssystem nach Anspruch 10, wobei der Steuerinformationskanal zur
intermittierenden Verbindung neben gewöhnlichen Steuerdaten die Steuerdaten überträgt,
die zeigen, dass in einem Zeitraum ab einer Übertragung einer großen Dateninformationsmenge
von einer Basisstation zu einer Mobilstation bis zu einer Antwort für die große Informationsmenge
keine Daten übertragen werden.
12. Mobilkommunikationssystem nach Anspruch 10, wobei das Mobilkommunikationssystem eine
Funkvermittlungsstelle aufweist, die ausgebildet ist, das Management eines Steuetinformationskanals
zur intermitterenden Verbindung auszuführen, und eine Funktion aufweist, mindestens
eine Basisstation beim Starten, Umschalten und Aussetzen des Steuerinformationskanals
zur intermittierenden Verbindung zu instruieren.
13. Mobilkommunikationssystem nach Anspruch 1, wobei ferner ein TDMA-Datenkanal als ein
genannter schneller Datenkanal verwendet wird und ein Zeitschlitz in dem TDMA-Datenkanal
ferner in eine Serie von Mikrozeitschlitzen unterteilt ist, wobei jeder der Mikrozeitschlitze
die gleiche Anzahl von Bits wie ein Zeitschlitz eines langsamen TDMA-Datenkanals aufweist.
14. Mobilkommunikationssystem nach Anspruch 13, das ferner einen Entzerrer aufweist, der
für einen schnellen TDMA-Datenkanal zu verwenden und so angeordnet ist, dass er mit
Ausnahme der Betriebsgeschwindigkeit den gleichen Aufbau wie ein Entzerrer hat, der
in einem langsamen TDMA-Datenkanal zu verwenden ist.
15. Mobilkommunikationssystem nach Anspruch 13, wobei dann, wenn ein schneller TDMA-Datenkanal
mit einer Vielzahl von Mikrozeitschlitzen ausgebildet ist, die Schutzzeit des schnellen
TDMA-Datenkanals in der Einheit eines Mikrozeitschlitzes in Abhängigkeit von der Bewegungsgeschwindigkeit
einer Mobilstation geändert wird.
16. Mobilkommunikationssystem nach Anspruch 13, wobei das System eine Funkvermittlungsstelle
aufweist, die so ausgebildet ist, dass sie den Aufbau eines Mikrozeitschlitzes in
einem schnellen TDMA-Datenkanal managt, und mit einer Funktion versehen ist, mindestens
eine Basisstation anzuweisen, den Aufbau eines Mikrozeitschlitzes einschließlich der
Länge einer Schutzzeit des schnellen TDMA-Datenkanals zu ändern.
17. Mobilkommunikationssystem nach Anspruch 1, wobei ferner die Basisstation und die Mobilstation
jeweils mit Vermittlungseinrichtungen versehen sind, um ein Kommunikationssystem zu
wählen, das imstande ist, eine erforderliche Informationsmenge synchron mit Zeitschlitzen
zu übertragen.
18. Mobilkommunikationssystem nach Anspruch 17, wobei eine Basisstation einen Speicher
zur Kanalzuweisung aufweist, was es ermöglicht, einen Downlink und einen Uplink zu
und von einer Mobilstation in einem Übertragungskanal so einzustellen, dass sie unabhängig
voneinander sind, wobei der Übertragungskanal mit einer Kombination aus einer Frequenz
und einem Zeitschlitz gebildet ist.
19. Mobilkommunikationssystem nach Anspruch 17, wobei das Mobilkommunikationssystem eine
Funkvermittlungsstelle aufweist, die ausgebildet ist, die Kanalzuweisung zu steuern,
und mit einer Funktion versehen ist, eine Basisstation bei der Zuweisung von Übertragungskanälen
zu instruieren.
20. Mobilkommunikationssystem nach Anspruch 1, wobei ferner eine Funkvermittlungsstelle,
die mit den Mobilstationen verbunden ist, mit einem Mobilstations-Informationsspeicher
versehen ist, um Funkinformationen einschließlich der Information zu speichern, die
Dienste zeigt, welche die genannten Mobilstationen in Anspruch nehmen können, die
von der Funkvermittlungsstelle gesteuert werden.
21. Mobilkommunikationssystem nach Anspruch 20, wobei eine Funkvermittlungsstelle ausgebildet
ist, das Management von Mobilstationsinformationen auszuführen, die von der Funkvermittlungsstelle
gesteuerte Mobilstationen betreffen, und eine Funktion aufweist, auf der Basis der
Mobilstationsinformationen mindestens eine Basisstation beim Starten, Umschalten und
Aussetzen von Diensten zu instruieren.
22. Mobilkommunikationssystem nach Anspruch 20, wobei eine Funkvermittlungsstelle ausgebildet
ist, das Management der Mobilstationsinformationen auszuführen, welche die von der
Funkvermittlungsstelle gesteuerten Mobilstationen betreffen, und wobei für den Fall,
dass eine Änderung in den Mobilstationsinformationen eintritt, die Funkvermittlungsstelle
mit einer Funktion versehen ist, die geänderten Mobilstationsinformationen an die
Datenbank des Mobilkommunikationssystems zu überführen, welche die Mobilstationsinformationen
enthält, die sämtliche Mobilstationen in dem Mobilkommunikationssystem betreffen.
23. Mobilkommunikationssystem nach Anspruch 1, wobei ferner eine Funkvermittlungsstelle,
die mit der Basisstation verbunden ist, mit einer Speichereinrichtung zur schnellen
Datenübertragung versehen ist, um die zu den Mobilstationen übertragenen schnellen
Daten zwischenzuspeichern.
24. Mobilkommunikationssystem nach Anspruch 23, wobei dann, wenn die schnellen Daten,
die von einer Funkvermittlungsstelle durch eine verbundene Basisstation übertragen
werden, normal in einer Mobilstation empfangen werden,
die Mobilstation dazu angepasst ist, eine Zeitschlitznummer der letzten schnellen
Daten zu detektieren, und ferner dazu angepasst ist, die Zeitschlitznummer als eine
normale Zeitschlitznummer durch die Basisstation zu der Funkvermittlungsstelle zu
übertragen.
25. Mobilkommunikationssystem nach Anspruch 24, wobei eine Funkvermittlungsstelle ausgebildet
ist, das Management von zu einer Mobilstation zu übertragenden schnellen Daten auszuführen,
und ferner ausgebildet ist, die normale Schlitznummer zu empfangen, die von der Mobilstation
übertragen wird, welche die schnellen Daten empfangen hat, und ferner ausgebildet
ist, schnelle Daten zu speichern, die Zeitschlitznummern an und nach der Schlitznummer
haben, die auf die normale Zeitschlitznummer in der Speichereinrichtung für schnelle
Übertragung folgt.
26. Mobilkommunikationssystem nach Anspruch 25, wobei eine Funkvermittlungsstelle ausgebildet
ist, das Management von zu einer Mobilstation zu übertragenden schnellen Daten auszuführen,
und wobei dann, wenn die Mobilstation die Funkvermittlungsstelle auffordert, die schnellen
Daten erneut zu übertragen, die Vermittlungsstelle ferner dazu angepasst ist, die
schnellen Daten, die Zeitschlitznummern an und nach der Zeitschlitznummer haben, die
auf die normale Zeitschlitznummer folgt, aus der Speichereinrichtung für schnelle
Datenübertragung zu lesen und die schnellen Daten durch die Basisstation zu der Mobilstation
zu übertragen.
27. Mobilkommunikationssystem nach Anspruch 23, wobei dann, wenn eine Funkvermittlungsstelle
dazu angepasst ist, die schnellen Daten zu empfangen, die von der Rufeinleitungsquelle
der schnellen Daten durch ein öffentliches Telefonwählnetz, in dem die Funkvermittlungsstelle
untergebracht ist, zu einer Mobilstation zu übertragen sind, und ferner dazu angepasst
ist, die Daten in der Speichereinrichtung für eine schnelle Übertragung zu speichern,
die schnellen Daten in Datenblöcke unterteilt werden, so dass jeder Datenblock in
einem Zeitschlitz übertragen werden kann, und jeder Block mit einer Speicherinformationsnummer
für das Management nummeriert wird.
28. Mobilkommunikationssystem nach Anspruch 27, wobei eine Basisstation, die zu einer
Mobilstation schnelle Daten übertragen hat, dazu angepasst ist, die Zeitschlitznummer
der übertragenen schnellen Daten mit der von der Funkvermittlungsstelle, mit welcher
die Basisstation verbunden ist, nummerierten Speicherinformationsnummer zu vergleichen,
und ferner dazu angepasst ist, die Zeitschlitznummer und die Speicherinformationsnummer
in ein Informationsset einzubinden, und ferner dazu angepasst ist, der Funkvermittlungsstelle
die Informationen mitzuteilen.
29. Mobilkommunikationssystem nach Anspruch 24, wobei eine Funkvermittlungsstelle ausgebildet
ist, das Management der zu Mobilstationen zu übertragenden schnellen Daten auszuführen,
und mit einer Funktion versehen ist, die schnellen Daten, die Zeitschlitznummern an
und vor der normalen Zeitschlitznummer haben, aus der Speichereinrichtung, in der
die schnellen Daten gespeichert sind, zu löschen.
30. Mobilkommunikationssystem nach Anspruch 24, wobei eine Funkvermittlungsstelle ausgebildet
ist, das Management der zu Mobilstationen zu übertragenden schnellen Daten auszuführen,
und mit Funktionen versehen ist, so dass dann, wenn eine Mobilstation die Übertragung
beendet, die Informationsmenge von schnellen Daten, die in der Speichereinrichtung
für schnelle Datenübertragung verblieben sind und Zeitschlitznummern an und nach der
Zeitschlitznummer haben, die auf die normale Zeitschlitznummer folgt, welche von der
Mobilstation durch die Basisstation übertragen worden ist, der Rufeinleitungsquelle
der schnellen Daten mitgeteilt wird.
31. Mobilkommunikationssystem nach Anspruch 26, wobei eine Funkvermittlungsstelle ausgebildet
ist, das Management der zu Mobilstationen zu übertragenden schnellen Daten auszuführen,
und die Funkvermittlungsstelle mit einer Funktion versehen ist, so dass dann, wenn
die von der Mobilstation angeforderten schnellen Daten an einer Basisstation zu einem
Zeitpunkt übertragen werden, zu dem die Informationsmenge der schnellen Daten, die
in der Speichereinrichtung für schnelle Datenübertragung verblieben sind, einen Wert
erreicht, der niedriger als ein vorbestimmter Wert ist, die Funkvermittlungsstelle
ferner dazu angepasst ist, die Übertragung der nachfolgenden schnellen Daten für die
Rufeinleitungsquelle der schnellen Daten durch das öffentliche Telefonwählnetz anzufordern.
32. Mobilkommunikationssystem nach Anspruch 23, wobei dann, wenn schnelle Daten, die von
einer Funkvermittlungsstelle durch eine verbundene Basisstation übertragen werden,
von einer Mobilstation nicht normal empfangen werden, die Mobilstation dazu angepasst
ist, die Zeitschlitznummer der übertragenen schnellen Daten zu detektieren und die
Nummer als eine abnormale Zeitschlitznummer zu der Funkvermittlungsstelle durch die
verbundene Basisstation zu übertragen.
33. Mobilkommunikationssystem nach Anspruch 32, wobei eine Funkvermittlungsstelle ausgebildet
ist, das Management der zu Mobilstationen zu übertragenden schnellen Daten auszuführen,
und wobei dann, wenn die schnellen Daten in einer Mobilstation nicht normal empfangen
werden, die Funkvermittlungsstelle bei Empfang der abnormalen Zeitschlitznummer dazu
angepasst ist, die schnellen Daten, welche die gleiche Zeitschlitznummer wie die abnormalen
Zeitschlitznummer haben, aus der Speichereinrichtung für schnelle Datenübertragung
zu lesen und die schnellen Daten zu der Mobilstation erneut zu übertragen.
34. Mobilkommunikationssystem nach Anspruch 1, wobei ferner die mit der Basisstation verbundene
Funkvermittlungsstelle mit einem Mobilstations-Managementspeicher versehen ist, um
eine Übertragungskanal-Managementtabelle zu speichern, die für das Management von
Übertragungskanälen zu verwenden ist, welche die Funkvermittlungsstelle und jeweilige
Mobilstationen verbinden, und
wobei die Funkvermittlungsstelle ausgebildet ist, einen Zeitschlitz zuzuweisen, der
dem Übertragungstyp entspricht, und nachdem der Vorgang der Zuweisung des dem aktuellen
Übertragungstyp entsprechenden Zeitschlitzes beendet ist, der Vorgang der Zuweisung
des Zeitschlitzes in dem Mobilstations-Managementspeicher als eine Vorgeschichte gespeichert
wird, und wenn der gleiche Übertragungstyp erneut angefordert wird, der Zeitschlitz
verwendet wird, der in der Vergangenheit, die in der Vorgeschichte in dem Mobilstations-Managementspeicher
existiert, tatsächlich verwendet wurde.
35. Mobilkommunikationssystem nach Anspruch 34, das ferner so ausgebildet ist, dass dann,
wenn der Name eines Zeitschlitzes, der eine Vorgeschichte der tatsächlichen Verwendung
in der Vergangenheit hat, in einem Mobilstations-Managementspeicher als ein gegenwärtig
nicht verwendeter Zeitschlitz gespeichert ist, nur dann, wenn ein Zeitschlitzname,
der keine Vorgeschichte der tatsächlichen Verwendung in der Vergangenheit für die
gleiche Art von Übertragungstyp hat, in dem Mobilstations-Managementspeicher nicht
gefunden wird, die Vorgeschichte des Zeitschlitznamens, der die Vorgeschichte der
tatsächlichen Verwendung in der Vergangenheit hat, aus dem Mobilstations-Managementspeicher
gelöscht und einer neuen Mobilstation zugewiesen wird.
36. Mobilkommunikationssystem nach Anspruch 35, das ferner so ausgebildet ist, dass dann,
wenn der Name eines Zeitschlitzes, der eine Vorgeschichte der tatsächlichen Verwendung
in der Vergangenheit hat, in einem Mobilstations-Managementspeicher als ein gegenwärtig
nicht verwendeter Zeitschlitz gespeichert ist, wenn ein Zeitschlitzname, der keine
Vorgeschichte der tatsächlichen Verwendung in der Vergangenheit für die gleiche Art
von Übertragungstyp hat, in dem Mobilstations-Managementspeicher nicht gefunden wird
und die Vorgeschichte des Zeitschlitznamens, der die Vorgeschichte der tatsächlichen
Verwendung in der Vergangenheit hat, aus dem Mobilstations-Managementspeicher gelöscht
ist, ein Zeitschlitz, der die älteste Vorgeschichte der tatsächlichen Verwendung in
der Vergangenheit hat, gewählt und einer neuen Mobilstation zugewiesen wird.
1. Système de communication mobile, comprenant :
une pluralité de stations mobiles et au moins une station de base, lesdites stations
mobiles et ladite station de base étant radioconnectées entre elles en utilisant un
système d'accès multiple qui est une combinaison de TDMA, FDMA et CDMA et où la liaison
montante et la liaison descendante sont séparées d'une manière TDD (duplexage par
répartition dans le temps),
dans lequel au moins une de ladite pluralité de stations mobiles est capable de choisir
entre une fonction de transmission de données CDMA à faible vitesse ou une fonction
de transmission de données TDMA à grande vitesse pour une radioconnexion à ladite
station de base, et dans lequel le canal de communication dudit système de communication
mobile est constitué d'un canal asymétrique, et
la quantité d'informations à transmettre dans la liaison montante ou la liaison descendante
n'est pas fixe, et selon les exigences dépendantes du système, la quantité d'informations
de liaison montante peut être supérieure ou inférieure à celle de la liaison descendante,
et
le choix entre un schéma d'accès multiple TDMA à grande vitesse ou CDMA à faible vitesse,
dans les deux directions montante et descendante, est déterminé selon la quantité
d'informations réelle à transmettre.
2. Système de communication mobile selon la revendication 1, dans lequel ledit système
comprend un centre de commutation mobile ayant une fonction servant à commander à
au moins une station de base de changer une quantité d'informations dans une liaison
montante depuis une station mobile jusqu'à une station de base, et une quantité d'informations
dans une liaison descendante depuis ladite station de base jusqu'à ladite station
mobile.
3. Système de communication mobile selon la revendication 1, adapté en outre pour, lorsque
la transmission de données d'une quantité importante d'informations est terminée dans
l'une ou dans les deux liaisons montante et descendante, commuter immédiatement sur
un canal de transmission d'une faible quantité de données.
4. Système de communication mobile selon la revendication 3 adapté pour, lorsqu'une station
de base et une station mobile sont radioconnectées avec un canal de transmission d'une
faible quantité de données, et si pendant une période de temps prédéterminée, une
transmission de données n'est pas exécutée, commuter sur un canal de contrôle pour
une connexion qui transmet uniquement des données de contrôle.
5. Système de communication mobile selon la revendication 4 configuré en outre pour que,
dans un état où une station de base et une station mobile sont radioconnectées avec
un canal de contrôle pour une connexion, s'il devient nécessaire de transmettre des
données d'une quantité importante d'informations dans l'une parmi une liaison montante
depuis ladite station mobile jusqu'à ladite station de base, ou une liaison descendante
depuis ladite station de base jusqu'à ladite station mobile, ou dans les deux, ledit
canal de contrôle pour une connexion puisse être immédiatement commuté sur un canal
de transmission d'une grande quantité de données.
6. Système de communication mobile selon la revendication 4 configuré en outre pour que,
lorsqu'une station de base et une station mobile sont radioconnectées avec un canal
de contrôle pour une connexion, s'il devient nécessaire de transmettre des données
d'une petite quantité d'informations dans l'une parmi une liaison montante depuis
ladite station mobile jusqu'à ladite station de base, ou une liaison descendante depuis
ladite station de base jusqu'à ladite station mobile, ou dans les deux, ledit canal
de contrôle pour une connexion soit immédiatement commuté sur un canal de transmission
d'une faible quantité de données.
7. Système de communication mobile selon la revendication 3 configuré en outre pour que,
lorsqu'une station de base et une station mobile sont radioconnectées avec un canal
de transmission d'une faible quantité de données, s'il devient nécessaire de transmettre
des données d'une quantité importante d'informations dans l'une parmi une liaison
montante depuis ladite station mobile jusqu'à ladite station de base, ou une liaison
descendante depuis ladite station de base jusqu'à ladite station mobile, ou dans les
deux, ledit canal de transmission d'une faible quantité de données soit immédiatement
commuté sur un canal de transmission de données de grande capacité.
8. Système de communication mobile selon la revendication 3, dans lequel ledit système
comprend un centre de commutation mobile comportant une fonction servant à commander
à au moins une station de base d'effectuer la gestion d'un canal de communication
asymétrique et le transfert dudit canal de communication asymétrique.
9. Système de communication mobile selon la revendication 1, dans lequel ledit système
de communication comprend en outre des canaux de transmission de données de faible
capacité utilisant un système multitrame qui sont indépendants les uns des autres
dans ladite liaison montante et ladite liaison descendante respectivement.
10. Système de communication mobile selon la revendication 9, dans lequel pendant la période
de temps où des données ne sont pas transmises entre une station de base et une station
mobile, ledit canal de transmission de données de faible capacité est un canal d'informations
de contrôle pour une connexion intermittente destinée à transmettre des données de
contrôle.
11. Système de communication mobile selon la revendication 10, dans lequel le canal d'informations
de contrôle pour une connexion intermittente transmet, outre des données de contrôle
ordinaires, les données de contrôle montrant qu'aucune donnée n'a été transmise dans
une période de temps située entre une transmission d'une quantité importante d'informations
depuis une station de base jusqu'à une station mobile et une réponse pour ladite grande
quantité d'informations.
12. Système de communication mobile selon la revendication 10, dans lequel ledit système
de communication mobile comprend un centre de commutation mobile qui est adapté pour
effectuer la gestion d'un canal d'informations de contrôle pour une connexion intermittente
et qui comprend une fonction servant à commander à au moins une station de base lors
de la mise en route, la commutation et la suspension dudit canal d'informations de
contrôle pour une connexion intermittente.
13. Système de communication mobile selon la revendication 1 dans lequel en outre un canal
de données TDMA est utilisé comme un dit canal de données à grande vitesse et un intervalle
de temps dans ledit canal de données TDMA est en outre divisé en une série de micro
intervalles de temps, chacun desdits micro intervalles de temps comprenant le même
nombre de bits qu'un intervalle de temps de canal de données TDMA à faible vitesse.
14. Système de communication mobile selon la revendication 13, comprenant en outre un
égalisateur utilisé pour un canal de données TDMA à grande vitesse conçu pour avoir
la même constitution qu'un égalisateur utilisé dans un canal de données TDMA à faible
vitesse, excepté la vitesse de fonctionnement.
15. Système de communication mobile selon la revendication 13, dans lequel lorsqu'un canal
de données TDMA à grande vitesse est constitué d'une pluralité de micro intervalles
de temps, le temps de garde du canal de données TDMA à grande vitesse est changé dans
l'unité d'un micro intervalle de temps selon la vitesse de déplacement d'une station
mobile.
16. Système de communication mobile selon la revendication 13, dans lequel ledit système
comprend un centre de commutation mobile qui est configuré pour gérer la constitution
d'un micro intervalle de temps dans un canal de données TDMA à grande vitesse et comporte
une fonction servant à commander à au moins une station de base de changer la constitution
d'un micro intervalle de temps y compris la longueur d'un temps de garde dudit canal
de données TDMA à grande vitesse.
17. Système de communication mobile selon la revendication 1, dans lequel ladite station
de base et ladite station mobile sont équipées de commutateurs respectivement pour
sélectionner un système de communication qui est capable de transmettre une quantité
d'informations nécessaire en synchronisation avec des intervalles de temps.
18. Système de communication mobile selon la revendication 17, dans lequel une station
de base comprend une mémoire pour une affectation de canal qui permet de rendre une
liaison descendante et une liaison montante vers/depuis une station mobile dans un
canal de communication, indépendantes l'une de l'autre, ledit canal de communication
étant constitué d'une combinaison d'une fréquence et d'un intervalle de temps.
19. Système de communication mobile selon la revendication 17, dans lequel ledit système
de communication mobile comprend un centre de commutation mobile qui est adapté pour
contrôler une affectation de canal et qui comporte une fonction servant à commander
à une station de base lors de l'affectation de canaux de communication.
20. Système de communication mobile selon la revendication 1, dans lequel en outre un
centre de commutation mobile connecté auxdites stations mobiles est équipé d'une mémoire
d'informations de station mobile destinée à stocker des informations de station mobile
incluant les informations montrant les services disponibles pour lesdites stations
mobiles qui sont sous le contrôle dudit centre de commutation mobile.
21. Système de communication mobile selon la revendication 20, dans lequel un centre de
commutation mobile est adapté pour effectuer la gestion des informations de station
mobile concernant les stations mobiles qui sont sous le contrôle dudit centre de commutation
mobile et comprend une fonction servant à commander à au moins une station de base
lors de la mise en route, la commutation et la suspension de services d'après lesdites
informations de station mobile.
22. Système de communication mobile selon la revendication 20, dans lequel un centre de
commutation mobile est adapté pour effectuer la gestion des informations de station
mobile concernant les stations mobiles qui sont sous le contrôle dudit centre de commutation
mobile, et dans le cas où une modification a lieu dans lesdites informations de station
mobile, ledit centre de commutation mobile comporte une fonction servant à transférer
les informations de station mobile modifiées vers la base de données dudit système
de communication mobile qui contient les informations de station mobile concernant
toutes les stations mobiles dans ledit système de communication mobile.
23. Système de communication mobile selon la revendication 1, dans lequel un centre de
commutation mobile connecté à ladite station de base est équipé d'un dispositif de
mémoire pour une communication de données à grande vitesse afin de stocker temporairement
les données à grande vitesse transmises auxdites stations mobiles.
24. Système de communication mobile selon la revendication 23, dans lequel lorsque les
données à grande vitesse transmises à partir d'un centre de commutation mobile par
l'intermédiaire d'une station de base connectée sont normalement reçues dans une station
mobile, ladite station mobile est adaptée pour détecter un numéro d'intervalle de
temps des dernières données à grande vitesse et est en outre adaptée pour transférer
le numéro d'intervalle comme un numéro d'intervalle normal au dit centre de commutation
mobile par l'intermédiaire de ladite station de base.
25. Système de communication mobile selon la revendication 24, dans lequel un centre de
commutation mobile est adapté pour effectuer la gestion de données à grande vitesse
à transmettre à une station mobile et est en outre adapté pour recevoir ledit numéro
d'intervalle de temps normal transmis à partir de ladite station mobile qui a reçu
lesdites données à grande vitesse, et est en outre adapté pour stocker des données
à grande vitesse ayant des numéros d'intervalle durant et après le numéro d'intervalle
qui suit le numéro d'intervalle normal dans le dispositif de mémoire pour une communication
à grande vitesse.
26. Système de communication mobile selon la revendication 25, dans lequel un centre de
commutation mobile est adapté pour effectuer la gestion de données à grande vitesse
à transmettre à une station mobile, et lorsqu'il y a une requête de ladite station
mobile au dit centre de commutation mobile pour transmettre à nouveau lesdites données
à grande vitesse, ledit centre de commutation est en outre adapté pour extraire les
données à grande vitesse ayant des numéros d'intervalle de temps durant et après le
numéro d'intervalle de temps qui suit le numéro d'intervalle de temps normal à partir
du dispositif de mémoire pour une communication de données à grande vitesse et pour
transmettre les données à grande vitesse à ladite station mobile par l'intermédiaire
de la station de base.
27. Système de communication mobile selon la revendication 23, dans lequel lorsqu'un centre
de commutation mobile est adapté pour recevoir les données à grande vitesse à transmettre
à une station mobile à partir de la source, émettrice de l'appel, des données à grande
vitesse par l'intermédiaire d'un réseau téléphonique public commuté dans lequel ledit
centre de commutation mobile est adapté pour stocker les données dans ledit dispositif
de mémoire pour une communication à grande vitesse, les données à grande vitesse sont
sectionnées en blocs de données afin que chaque bloc de données puisse être transmis
dans un intervalle de temps, et chaque bloc est numéroté avec un numéro d'informations
de stockage à des fins de gestion.
28. Système de communication mobile selon la revendication 27, dans lequel une station
de base qui a transmis des données à grande vitesse à une station mobile est adaptée
pour comparer le numéro d'intervalle de temps des données à grande vitesse transmises
avec le numéro d'informations de stockage numéroté par le centre de commutation mobile
auquel la station de base est connectée, et est en outre adaptée pour incorporer ledit
numéro d'intervalle de temps et ledit numéro d'informations de stockage dans un ensemble
d'informations et est en outre adaptée pour notifier les informations au dit centre
de commutation mobile.
29. Système de communication mobile selon la revendication 24, dans lequel un centre de
commutation mobile est adapté pour effectuer la gestion des données à grande vitesse
à transmettre à des stations mobiles et comporte une fonction servant à effacer les
données à grande vitesse ayant des numéros d'intervalle de temps durant et avant le
numéro d'intervalle de temps normal à partir du dispositif de mémoire dans lequel
les données à grande vitesse sont stockées.
30. Système de communication mobile selon la revendication 24, dans lequel un centre de
commutation mobile est adapté pour effectuer la gestion des données à grande vitesse
à transmettre à des stations mobiles et comporte des fonctions pour que, lorsqu'une
station mobile finit une communication, la quantité d'informations de données à grande
vitesse restées dans le dispositif de mémoire pour une communication de données à
grande vitesse ayant des numéros d'intervalle de temps durant et après le numéro d'intervalle
de temps qui suit le numéro d'intervalle de temps normal transmis à partir de ladite
station mobile par l'intermédiaire de la station de base soit notifiée à la source,
émettrice de l'appel, desdites données à grande vitesse.
31. Système de communication mobile selon la revendication 26, dans lequel un centre de
commutation mobile est adapté pour effectuer la gestion des données à grande vitesse
à transmettre à des stations mobiles et le centre de commutation mobile comporte une
fonction pour que, lorsque lesdites données à grande vitesse demandées par ladite
station mobile sont transmises à une station de base, au moment où la quantité d'informations
desdites données à grande vitesse restées dans le dispositif de mémoire pour une communication
de données à grande vitesse atteint un niveau inférieur à un niveau prédéterminé,
le centre de commutation mobile soit en outre adapté pour demander la transmission
des données à grande vitesse suivantes pour la source, émettrice de l'appel, des données
à grande vitesse par l'intermédiaire du réseau téléphonique public commuté.
32. Système de communication mobile selon la revendication 23, dans lequel lorsque des
données à grande vitesse transmises à partir d'un centre de commutation mobile par
l'intermédiaire d'une station de base connectée ne sont pas reçues normalement par
une station mobile, la station mobile est adaptée pour détecter le numéro d'intervalle
de temps des données à grande vitesse transmises et pour transmettre le numéro comme
un numéro d'intervalle de temps anormal au dit centre de commutation mobile par l'intermédiaire
de la station de base connectée.
33. Système de communication mobile selon la revendication 32, dans lequel un centre de
commutation mobile est adapté pour effectuer la gestion des données à grande vitesse
à transmettre à des stations mobiles, et lorsque lesdites données à grande vitesse
ne sont pas reçues normalement dans une station mobile, le centre de commutation mobile,
à la réception du numéro d'intervalle de temps anormal, est adapté pour extraire les
données à grande vitesse ayant le même numéro d'intervalle de temps comme le numéro
d'intervalle de temps anormal à partir du dispositif de mémoire pour une communication
de données à grande vitesse, et pour transmettre à nouveau les données à grande vitesse
à ladite station mobile.
34. Système de communication mobile selon la revendication 1, dans lequel ledit centre
de commutation mobile connecté à ladite station de base est équipé d'une mémoire de
gestion de station mobile destinée à stocker une table de gestion de canaux de communication
à utiliser pour la gestion des canal de communication connectant ledit centre de commutation
mobile et les stations mobiles respectives, et dans lequel ledit centre de commutation
mobile est adapté pour affecter un intervalle de temps correspondant au type de transmission
et après que l'opération d'affectation de l'intervalle de temps correspondant au type
de transmission courant est terminée, l'opération d'affectation de l'intervalle de
temps est stockée dans ladite mémoire de gestion de station mobile en tant qu'historique,
et dans le cas où le même type de transmission est demandé à nouveau, l'intervalle
de temps ayant une utilisation réelle dans le passé existant dans l'historique de
ladite mémoire de gestion de station mobile est utilisé.
35. Système de communication mobile selon la revendication 34 configuré en outre pour
que, lorsque le nom d'un intervalle de temps qui a un historique d'utilisation réelle
dans le passé est stocké dans une mémoire de gestion de station mobile en tant qu'intervalle
de temps non utilisé présentement, seulement lorsqu'un nom d'intervalle de temps qui
n'a pas un historique d'utilisation réelle dans le passé de la même sorte de type
de transmission n'est pas trouvé dans ladite mémoire de gestion de station mobile,
l'historique du nom d'intervalle de temps qui a l'historique d'utilisation réelle
dans le passé soit effacé de ladite mémoire de gestion de station mobile et qu'il
soit affecté à une nouvelle station mobile.
36. Système de communication mobile selon la revendication 35 configuré en outre pour
que, lorsque le nom d'un intervalle de temps qui a un historique d'utilisation réelle
dans le passé est stocké dans une mémoire de gestion de station mobile en tant qu'intervalle
de temps non utilisé présentement, lorsqu'un nom d'intervalle de temps qui n'a pas
un historique d'utilisation réelle dans le passé de la même sorte de type de transmission
n'est pas trouvé dans ladite mémoire de gestion de station mobile et que l'historique
du nom d'intervalle de temps qui a l'historique d'utilisation réelle dans le passé
a été effacé de ladite mémoire de gestion de station mobile, un intervalle de temps
qui a l'historique d'utilisation réelle le plus ancien dans le passé soit sélectionné
et qu'il soit affecté à une nouvelle station mobile.