[0001] The present invention relates to a digital broadcast receiving apparatus and a digital
broadcast receiving method, and is particularly applied to a digital broadcast receiving
apparatus having a function of appropriately updating channels registered in a preset
memory with movement of a vehicle.
[0002] In an in-vehicle digital broadcast receiving apparatus, when a vehicle moves and
crosses into a different broadcast area, a digital broadcast of a channel being viewed
and listened to until then is no longer able to be received. In response to this problem,
there is provided a function in which, if a reception strength of the channel being
viewed and listened to decreases to a predetermined value or lower, a channel scan
of all frequencies is started in the background, and channels registered in a preset
memory are automatically updated.
[0003] For example, as illustrated in Fig. 4, in the case where a vehicle is moving from
a broadcast area of Fukushima prefecture into a broadcast area of Ibaraki prefecture,
because a reception strength of a channel being viewed and listened to until then
decreases to a predetermined value or lower near the border between Fukushima and
Ibaraki prefectures which the vehicle crosses, a scan is performed and channels registered
in a preset memory are automatically updated.
[0004] In this case, because the scan is performed at the border, some channels in Fukushima
prefecture may be scanned and preset even though the vehicle is moving away from Fukushima
prefecture. However, even if the channels are preset, the preset channels are not
able to be received immediately because the vehicle is moving away from the broadcast
area of Fukushima prefecture.
[0005] In addition, a technique has been suggested in which it is determined whether or
not a detected frequency of a broadcasting station is the same as a specific frequency
(for example, 1620 kHz for traffic information), and the frequency is not stored in
a preset memory if it is determined that the frequency is the same as the specific
frequency (see, for example,
JP 6-303108 A). This technique may prevent a frequency of a traffic information broadcasting station
for which a dedicated switch is provided from being unnecessarily stored in the preset
memory, and prevent a range of channel selection using a preset switch from narrowing.
[0006] EP 1 659 711 A1 discloses a vehicle entertainment and information processing system comprising a
tuning receiver for receiving broadcast signals from at least one of a plurality of
broadcast stations, a navigation unit for outputting position data in real time according
to the vehicle's movement, a database containing broadcast station information, and
means for determining a reception quality parameter of at least one of the plurality
of broadcast stations based on the position data and the broadcast station information.
EP 1 659 711 A1 further discloses a corresponding method.
[0007] According to
EP 1 148 641 A2 a controller with a memory is contained in a navigation device or in a first RDS
receiver and can be part of a vehicle's on-board computer. Input and output devices
can form a structural unit and be operated via a touch-screen display. A second RDS
receiver has a tuner, an RDS decoder and a radio receiver comprising a GSM mobile
telephone with an antenna and an interface connecting the mobile telephone to the
controller.
[0008] US 2008/182533 A1 discloses a method for determining a region where a broadcasting receiver is located
by detecting the signal strength of a plurality of channels. When a user takes the
broadcasting receiver from region A to region B, the broadcasting receiver provides
a list of regions including region B when the broadcasting receiver is turned on.
When the user chooses to change the current region to region B, and after the channel
scan is performed, the user can effortlessly view the broadcast programs of region
B.
[0009] US 5 280 642 A describes provides a radio receiver which is capable of automatically identifying
the region from which a specific frequency is being received, for example, the name
of a city or the like only by receiving the frequency therefrom. In the radio receiver
according to the present invention as above, first all the reception frequencies within
a broadcast reception band are swept to detect the relationship between each of the
reception frequencies and level of the electric field intensity of each reception
frequency, whereby all the reception frequencies are divided into two groups; the
first and second groups, depending on the level of the electric field of each reception
frequency. Whereafter, within the region codes stored in the first memory means, those
having more number of reception frequencies defined in the first group than a predetermined
number are selected, then the nearby regions of the thus selected region codes are
searched from the second memory means, so that in the case that the nearby region
also includes more number of the reception frequencies defined in the second group
than a predetermined number, the region of the thus selected region code is determined
as a frequency reception region of this moment.
[0010] A technique called "area preset" also exists in which area preset information representing
a list of receivable channels is stored in a database in advance for each broadcast
area and area preset information of a broadcast area corresponding to a current location
of a vehicle is read out and stored in a preset memory. However, there are problems
that, because the accuracy of area preset information is poor, some channels are not
able to be received immediately after they have been preset, and that a preset channel
is not able to be received with movement of the vehicle even in the same broadcast
area.
[0011] The present invention has been accomplished in order to solve such problems, and
an object thereof is to perform, in accordance with a decrease in a reception strength
of a channel being viewed and listened to, a scan so as to prevent an unnecessary
channel from being preset which is more likely not to be able to be received immediately
when channels registered in a preset memory are automatically updated.
[0012] The invention relates to a digital broadcast receiving apparatus and a method for
receiving a digital broadcast according to the independent claims. Embodiments are
disclosed in the dependent claims.
[0013] According to the present invention, if a reception strength of a channel has become
a predetermined value or lower, receivable channels are scanned, except for channels
whose area codes coincide with an area code of a channel currently being received,
and the receivable channels extracted by performing the scan are stored in a preset
memory.
[0014] According to the present invention configured as described above, while a vehicle
is moving and crossing into a different broadcast area, when automatic updating in
a preset memory is performed because a reception strength of a channel being received
in a broadcast area of an origin of movement has decreased, channels involved in the
broadcast area of the origin of movement are not preset, and only channels involved
in a broadcast area which is likely to be a destination of movement are preset. This
may prevent unnecessary channels which are more likely not to be able to be received
immediately with movement of the vehicle from being preset.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015]
Fig. 1 illustrates an example of the configuration of a digital broadcast receiving
apparatus according to an embodiment;
Figs. 2A to 2D illustrate an example of operations performed by the digital broadcast
receiving apparatus according to the embodiment;
Fig. 3 is a flowchart illustrating an example of operations performed by the digital
broadcast receiving apparatus according to the embodiment; and
Fig. 4 illustrates an example of a situation in which automatic updating in a preset
memory is performed because of a decrease in a reception strength.
[0016] An embodiment of the present invention will be described below with reference to
the drawings.
[0017] Fig. 1 illustrates an example of the configuration of a digital broadcast receiving
apparatus according to the embodiment. In the configuration of the digital broadcast
receiving apparatus illustrated in Fig. 1, an antenna 1 receives radio waves of digital
broadcasts modulated using a digital modulation method complying with an Integrated
Services Digital Broadcasting (ISDB) standard or Digital Audio Broadcasting (DAB)
standard. A tuner 2 selectively extracts, from the radio waves of the digital broadcasts
received by the antenna 1, a broadcast wave signal of a reception frequency which
matches an intended channel, and outputs the broadcast wave signal.
[0018] An OFDM demodulation unit 3 performs Orthogonal Frequency-Division Multiplexing (OFDM)
demodulation on the broadcast wave signal received with the tuner 2 and obtains a
transport stream (hereinafter referred to as a TS). An error correction unit 4 performs
error correction on the TS obtained through demodulation performed by the OFDM demodulation
unit 3 so as to correct an error having occurred in a transmission line.
[0019] A demultiplexer unit 5 divides the multiplexed TS to obtain an audio stream, a video
stream, and a data stream. Then, the demultiplexer unit 5 outputs the audio stream
to an audio decoder unit 6, outputs the video stream to a video decoder unit 7, and
outputs the data stream to a data decoder unit 8. In the data stream here, information
on a channel, such as the name of a broadcasting station and a physical channel (reception
frequency) of the broadcasting station, and an area code representing an area in which
a broadcast wave of the channel can be received are contained.
[0020] In addition, in the ISDB standard, which is a Japanese digital broadcast method,
the area code is composed of 12-bit data. The first 1 to 6 bits of 12 bits are assigned
as an identifier of a general area (including a wide area). This enables unique identification
of all general areas, which are, for example, 47 prefectures in Japan, island regions,
and wide areas. In addition, the first 7 to 12 bits of 12 bits are assigned as a region
identifier of a small area in a general area (including a wide area). This enables
unique identification of 64 regions in the general area.
[0021] Furthermore, in the DAB standard, which is a European digital radio broadcast method,
this area code is contained in an identification code, which is referred to as a service
identifier (SId) for identifying a broadcasting station, composed of four hexadecimal
digits. The area code is assigned to the second digit of the four-hexadecimal-digit
code. In addition, the first digit denotes a country code, and the third and fourth
digits denote a broadcasting station code. For example, when a Sid is C201, C denotes
a country code, 2 denotes an area code, and 01 denotes a broadcasting station code.
[0022] The audio decoder unit 6 decodes the input audio stream and outputs it as an audio
signal. The video decoder unit 7 decodes the input video stream and outputs it as
a video signal. The data decoder unit 8 decodes the input data stream and outputs
it as control data.
[0023] In response to the user's operation of an operation unit, which is not illustrated,
a channel switching unit 9 selects a channel to be received by the tuner 2 and switches
to it. A preset memory 10 associates pieces of information on a plurality of receivable
channels with a plurality of preset numbers and stores them. For each preset number,
information on a physical channel and an area code of a broadcasting station is stored
in this preset memory 10.
[0024] When the user operates a preset selection button (not illustrated) of the operation
unit to optionally select any preset number, the channel switching unit 9 sets, for
the tuner 2, as a reception channel, a physical channel that is associated with the
selected preset number and stored in the preset memory 10.
[0025] A reception strength determination unit 11 determines whether or not a reception
strength of a channel currently being received by the tuner 2 has become a predetermined
value or lower. This determines whether or not a vehicle is moving and crossing into
a different broadcast area. That is, as illustrated in Fig. 4, when the vehicle is
moving and crossing into a different broadcast area, a reception strength of a channel
being viewed and listened to until then decreases. Thus, if the reception strength
becomes the predetermined value or lower, it may be determined that the vehicle is
moving from a current broadcast area into a different broadcast area. In addition,
the reception strength may be detected by utilizing, for example, a carrier-to-noise
ratio (C/N) and a bit error rate (BER).
[0026] If the reception strength determination unit 11 determines that the reception strength
has become the predetermined value or lower, a scan processing unit 12 scans receivable
channels whose reception strengths exceed the predetermined value, except for channels
whose area codes coincide with an area code of the channel currently being received.
A scan process is a process in which a reception frequency of the tuner 2 is changed
and channels that can be received at a current location are detected to generate a
channel list. When the scan process is performed, the scan processing unit 12 acquires,
from the data decoder unit 8, information on physical channels and area codes of broadcasting
stations that can be received at the current location.
[0027] In a typical scan process, a scan of all frequencies (all channels) is performed.
On the other hand, in the embodiment, a scan of channels is performed, except for
channels whose area codes coincide with an area code of a channel currently being
received. The area code of the channel currently being received is acquired from the
data decoder unit 8. For example, as illustrated in Fig. 4, while the vehicle is moving
from the broadcast area of Fukushima prefecture into the broadcast area of Ibaraki
prefecture, in the case where a scan process is performed because a reception strength
of a channel currently being received has decreased, the scan processing unit 12 performs
a scan process on only channels other than channels to which an area code of Fukushima
prefecture (hereinafter referred to as a Fukushima code) is assigned.
[0028] A preset update unit 13 performs updating and stores receivable channels extracted
by the scan processing unit 12 in the preset memory 10. As described above, information
to be stored is information on physical channels and area codes of broadcasting stations
extracted as receivable channels by the scan processing unit 12.
[0029] Here, in the case where the scan processing unit 12 extracts a larger number of receivable
channels than the number of channels that can be registered in the preset memory 10,
for example, the preset update unit 13 stores the channels in the preset memory 10
in order of highest to lowest reception strength. In this case, as for a plurality
of receivable channels to be stored in the preset memory 10, there may exist channels
associated with a plurality of area codes in a mixed state.
[0030] For example, as illustrated in Fig. 4, in the case where the vehicle is moving from
the broadcast area of Fukushima prefecture toward the broadcast area of Ibaraki prefecture,
there is the possibility that the scan processing unit 12 may extract channels to
which an area code of Tochigi prefecture (hereinafter referred to as a Tochigi code)
is assigned in addition to channels to which an area code of Ibaraki prefecture (hereinafter
referred to as a Ibaraki code) is assigned. In this case, the preset update unit 13
stores the channels having the Ibaraki code and the channels having the Tochigi code
in the preset memory 10 in order of highest to lowest reception strength.
[0031] Alternatively, the preset update unit 13 may store, in the preset memory 10, only
channels having the most frequently extracted area code among receivable channels
extracted by the scan processing unit 12. For example, it is assumed that, among receivable
channels extracted by the scan processing unit 12, the number of extracted channels
having the Ibaraki code is largest. In this case, even if the scan processing unit
12 extracts channels having the Tochigi code, the preset update unit 13 does not store
these channels in the preset memory 10, and stores only the channels having the Ibaraki
code in the preset memory 10.
[0032] A reception strength of a channel currently being received varies depending on the
driving environment at the moment. Because of this, even though the vehicle is not
crossing into a different broadcast area, the reception strength may become the predetermined
value or lower only for an unspecified time period. Therefore, the reception strength
determination unit 11 may determine whether or not a state in which the reception
strength of the channel currently being received is the predetermined value or lower
has lasted for a predetermined time period or longer. Even if this is done, however,
when the vehicle is traveling through, for example, an area dense with buildings or
a mountainous area, the state in which the reception strength of the channel currently
being received is the predetermined value or lower may last for the predetermined
time period or longer even though the vehicle is not crossing into a different broadcast
area.
[0033] Thus, if it is determined that the reception strength of the channel currently being
received has become the predetermined value or lower, the reception strength determination
unit 11 may further determine whether or not, among channels currently stored in the
preset memory 10, reception strengths of channels whose area codes coincide with an
area code of the channel currently being received have become the predetermined value
or lower. The area code of the channel currently being received is acquired from the
data decoder unit 8. If the reception strength determination unit 11 determines that
the reception strength of the channel currently being received and the reception strengths
of a predetermined proportion or more of the channels whose area codes coincide with
the area code of the channel currently being received have become the predetermined
value or lower, the scan processing unit 12 performs a scan process on receivable
channels.
[0034] This enables more accurate detection of the fact that the vehicle is moving and crossing
into a different broadcast area. That is, as illustrated in Fig. 4, in the case where
the vehicle is moving from the broadcast area of Fukushima prefecture into the broadcast
area of Ibaraki prefecture, there is a high possibility that reception strengths of
other channels to which the area code of Fukushima prefecture is assigned as well
as the reception strength of the channel currently being received will decrease to
the predetermined value or lower. On the other hand, when the vehicle is traveling
through an area between buildings, a mountainous area, or the like, although reception
strengths of some channels decrease, not all reception strengths of a predetermined
proportion or more of channels having the same area code decrease. Hence, the employment
of the above-described determination method enables more accurate detection of the
fact that the vehicle is moving and crossing into a different broadcast area.
[0035] Figs. 2A to 2D illustrate an example of operations performed by the digital broadcast
receiving apparatus according to the embodiment configured as described above. Fig.
2A illustrates an example of information stored in the preset memory 10 before updating.
In the example of Fig. 2A, eleven receivable channels can be registered in the preset
memory 10, and channels having the Fukushima code and channels having the Ibaraki
code are stored in a mixed state. It is assumed that "ch 18" having the Fukushima
code among these channels is a channel currently being received.
[0036] It is assumed that the vehicle is moving from the broadcast area of Fukushima prefecture
into the broadcast area of Ibaraki prefecture and the reception strength determination
unit 11 determines that a reception strength of the channel currently being received
has become the predetermined value or lower. In this case, as illustrated in Fig.
2B, the reception strength determination unit 11 continues to determine whether or
not, among the channels currently stored in the preset memory 10, reception strengths
of channels having the Fukushima code which is the same as the area code of the channel
currently being received have become the predetermined value or lower.
[0037] Then, if the reception strength determination unit 11 determines that, among nine
channels having the Fukushima code stored in the preset memory 10, reception strengths
of the predetermined proportion or more of the channels have become the predetermined
value or lower, the scan processing unit 12 performs a scan process on channels, except
for the channels having the Fukushima code, as illustrated in Fig. 2C. Finally, as
illustrated in Fig. 2D, the preset update unit 13 stores, in the preset memory 10,
only channels having the most frequently extracted Ibaraki code among receivable channels
extracted by the scan processing unit 12.
[0038] Fig. 3 is a flowchart illustrating an example of operations performed by the digital
broadcast receiving apparatus according to the embodiment configured as described
above. The flowchart illustrated in Fig. 3 starts when a power supply of the digital
broadcast receiving apparatus is turned on.
[0039] First, the reception strength determination unit 11 detects a reception strength
of a channel currently being received (step S1), and determines whether or not the
detected reception strength has become a predetermined value or lower (step S2). If
the reception strength has not become the predetermined value or lower, the process
returns to step S1.
[0040] On the other hand, if the reception strength has become the predetermined value or
lower, the reception strength determination unit 11 subsequently selects, among channels
currently stored in the preset memory 10, one channel whose area code coincides with
an area code of the channel currently being received. Then, the reception strength
determination unit 11 detects a reception strength of the selected channel (step S3),
and determines whether or not the detected reception strength has become the predetermined
value or lower (step S4).
[0041] Here, if the reception strength of the selected channel has not become the predetermined
value or lower, the process returns to step S1. On the other hand, if the reception
strength of the selected channel has become the predetermined value or lower, the
reception strength determination unit 11 selects all channels whose area codes coincide
with the area code of the channel currently being received and determines whether
or not determinations of reception strengths of all the channels have been completed
(step S5). If determinations of the reception strengths of all the channels have not
been completed, the process returns to step S3.
[0042] On the other hand, among the channels currently stored in the preset memory 10, if
determinations of the reception strengths of all the channels whose area codes coincide
with the area code of the channel currently being received have been completed, that
is, if it is determined that all the reception strengths have become the predetermined
value or lower, the scan processing unit 12 scans receivable channels whose reception
strengths exceed the predetermined value, except for the channels whose area codes
coincide with the area code of the channel currently being received (step S6).
[0043] Then, the preset update unit 13 performs updating and stores the receivable channels
extracted by the scan processing unit 12 in the preset memory 10 (step S7). Subsequently,
the digital broadcast receiving apparatus determines whether or not the power supply
has been turned off (step S8), and if the power supply has not been turned off, the
process returns to step S1. If the power supply has been turned off, the process of
the flowchart illustrated in Fig. 3 ends.
[0044] As described in detail above, in the embodiment, if a reception strength of a channel
currently being received has become a predetermined value or lower, receivable channels
are scanned, except for channels whose area codes coincide with an area code of the
channel currently being received, and updating is performed and the receivable channels
extracted by performing the scan are stored in the preset memory 10.
[0045] According to the embodiment configured in this way, while a vehicle is moving and
crossing into a different broadcast area, when automatic updating in the preset memory
10 is performed because a reception strength of a channel being received in a broadcast
area of an origin of movement has decreased, channels involved in the broadcast area
(Fukushima code) of the origin of movement are not preset, and only channels involved
in a broadcast area (Ibaraki code or Tochigi code) which is likely to be a destination
of movement are preset. This may prevent unnecessary channels (channels involved in
the broadcast area of the origin of movement) which are more likely not to be able
to be received immediately with movement of the vehicle from being preset.
[0046] Furthermore, according to the embodiment, a scan process is performed on channels,
except for channels whose area codes coincide with an area code of a channel currently
being received, thereby offering an advantage in that a scan time period may be reduced.
[0047] In addition, in the embodiment, an example has been described in which the scan processing
unit 12 performs a scan process on channels, except for channels whose area codes
coincide with an area code of a channel currently being received, and the preset update
unit 13 stores, in the preset memory 10, the receivable channels extracted by performing
the scan process; however, the present invention is not limited to this.
[0048] For example, as in a typical scan process, the scan processing unit 12 performs a
scan process on all frequencies (all channels). Then, the preset update unit 13 may
select, among the receivable channels extracted by the scan processing unit 12, only
channels whose area codes differ from an area code of a channel currently being received,
and store them in the preset memory 10. However, the embodiment is desirable in that
it has an advantage in that a scan time period may be reduced.
[0049] Furthermore, in the embodiment, as for a plurality of receivable channels to be stored
in the preset memory 10, there have been described two cases, that is, the case where
channels associated with a plurality of area codes are stored in a mixed state, and
the case where only channels having an area code most frequently extracted by the
scan processing unit 12 are stored; however, either of the two cases may be automatically
selected in accordance with circumstances. For example, a navigation device is connected
to the digital broadcast receiving apparatus, and thus either of the two cases may
be automatically selected in accordance with a state of a guidance route setting.
[0050] For example, a notification of broadcast areas respectively represented by area codes
second and subsequent most frequently extracted by the scan processing unit 12 among
area codes of receivable channels is provided to the navigation device, and an inquiry
is made as to whether or not a guidance route set in the navigation device exists
within the broadcast areas. Then, if the guidance route does not exist within the
broadcast areas respectively represented by the second and subsequent most frequently
extracted area codes, only channels having an area code most frequently extracted
by the scan processing unit 12 are stored in the preset memory 10. On the other hand,
if the guidance route exists within the broadcast areas respectively represented by
the second and subsequent most frequently extracted area codes, a plurality of area
codes are allowed to exist in a mixed state, and receivable channels are stored in
the preset memory 10. This enables useful channels involved in a broadcast area through
which a vehicle is more likely to move along the guidance route to be stored in the
preset memory 10.
[0051] In addition, regardless of whether or not a broadcast area in which the guidance
route exists is any of the broadcast areas respectively represented by the second
and subsequent most frequently extracted area codes, the preset update unit 13 may
select, among receivable channels extracted by the scan processing unit 12, channels
in the broadcast area in which the guidance route exists, and store them in the preset
memory 10.
[0052] Furthermore, in the embodiment, the digital broadcast receiving apparatus that receives
a digital broadcast complying with the ISDB standard or DAB standard is used; however,
the digital broadcast receiving apparatus is applicable to a digital broadcast as
long as it complies with a digital broadcasting standard having area codes.
[0053] In addition, the above embodiment is merely an example of an embodiment for implementing
the present invention, and the technical scope of the present invention should not
be construed in a limited manner due to the above embodiment.
1. A digital broadcast receiving apparatus comprising:
a tuner (2) configured to receive a digital broadcast wave signal of a reception frequency
matching an intended channel, the digital broadcast wave signal comprising an area
code representing an area in which the broadcast wave of the intended channel can
be received:
reception strength determination means (11) configured to determine whether or not
a reception strength of the received digital broadcast wave signal has become a predetermined
value or lower;
scan processing means (12) configured to change the reception frequency of the tuner
(2) and to generate a receivable channel list from the channels matching receivable
digital broadcast wave signals whose reception strengths exceed the predetermined
value, except for channels matching digital broadcast wave signals whose area codes
coincide with the area code of the digital broadcast wave signal currently being received,
if the reception strength determination means (11) determines that the reception strength
has become the predetermined value or lower; and
preset update means (13) configured to perform updating and store the receivable channel
list generated by the scan processing means (12) in a preset memory (10).
2. The digital broadcast receiving apparatus according to Claim 1, wherein the digital
broadcast wave signal is a digital broadcast wave signal modulated using a digital
modulation method complying with at least an ISDB standard or DAB standard.
3. The digital broadcast receiving apparatus according to Claim 1 or 2,
wherein the reception strength determination means (11) is configured to determine
whether or not a reception strength of the digital broadcast wave signal currently
being received has become the predetermined value or lower, and if the reception strength
determination means (11) determines that the reception strength has become the predetermined
value or lower, the reception strength determination means (11) is configured to further
determine whether or not, among channels currently stored in the preset memory (10),
reception strengths of digital broadcast wave signals matching channels whose area
codes coincide with the area code of the digital broadcast wave signal matching the
channel currently being received have become the predetermined value or lower, and
wherein if the reception strength determination means (11) determines that the reception
strength of the digital broadcast wave signal matching the channel currently being
received and reception strengths of a predetermined proportion or more of the digital
broadcast wave signals matching the channels whose area codes coincide with the area
code of the digital broadcast wave signal matching the channel currently being received
have become the predetermined value or lower, the scan processing means (12) is configured
for changing the reception frequency of the tuner (2) and generating a receivable
channel list from the receivable digital broadcast wave signals whose reception strengths
exceed the predetermined value.
4. The digital broadcast receiving apparatus according to one of Claims 1-3, wherein
the preset update means (13) is configured to store, in the preset memory (10), only
channels matching digital broadcast wave signals having a most frequently extracted
area code among the receivable channels extracted by the scan processing means (12).
5. A method for receiving a digital broadcast wave signal comprising:
a first step of determining whether or not a reception strength of a digital broadcast
wave signal matching a channel currently being received by a tuner (2) has become
a predetermined value or lower, the digital broadcast wave signal comprising an area
code representing an area in which the broadcast wave can be received;
a second step of changing the reception frequency of the tuner (2) and generating
a receivable channel list from the receivable digital broadcast wave signals whose
reception strengths exceed the predetermined value, except for channels matching digital
broadcast wave signals whose area codes coincide with an area code of the digital
broadcast wave signal currently being received, if it is determined that the reception
strength has become the predetermined value or lower; and
a third step of performing updating and storing the generated receivable channel list
in a preset memory (10).
6. The method according to Claim 5, wherein the digital broadcast wave signal is a digital
broadcast wave signal modulated using a digital modulation method complying with at
least an ISDB standard or DAB standard.
7. The method according to Claim 5 or 6,
wherein the first step further includes a step of, if it is determined that the reception
strength of the digital broadcast wave signal matching the channel currently being
received has become the predetermined value or lower, further determining whether
or not, among the channels currently stored in the preset memory (10), the reception
strengths of the digital broadcast wave signals matching the channels whose area codes
coincide with the area code of the channel currently being received have become the
predetermined value or lower, and
wherein the second step further includes a step of, if it is determined that the reception
strength of the digital broadcast wave signal matching the channel currently being
received and the reception strengths of a predetermined proportion or more of the
digital broadcast wave signals matching the channels whose area codes coincide with
the area code of the digital broadcast wave signal matching the channel currently
being received have become the predetermined value or lower, changing the reception
frequency of the tuner (2) and generating a receivable channel list from the receivable
digital broadcast wave signals whose reception strengths exceed the predetermined
value.
8. The method according to one of Claims 5-7, wherein the third step further includes
a step of storing, in the preset memory (10), only channels matching digital broadcast
wave signals having a most frequently extracted area code among the receivable channels
extracted by the scanning.
1. Digitale Rundfunkempfangsvorrichtung, die umfasst:
einen Tuner (2), der dazu ausgelegt ist, ein digitales Rundfunkwellensignal einer
Empfangsfrequenz, die einem beabsichtigten Kanal entspricht, zu empfangen, wobei das
digitale Rundfunkwellensignal einen Gebietscode umfasst, der ein Gebiet darstellt,
in dem die Rundfunkwelle des beabsichtigten Kanals empfangen werden kann:
eine Empfangsstärkenbestimmungseinrichtung (11), die dazu ausgelegt ist, zu bestimmen,
ob eine Empfangsstärke des empfangenen digitalen Rundfunkwellensignals ein vorbestimmter
Wert oder niedriger geworden ist;
eine Abtastverarbeitungseinrichtung (12), die dazu ausgelegt ist, die Empfangsfrequenz
des Tuners (2) zu ändern und eine Liste empfangbarer Kanäle von den Kanälen zu erzeugen,
die empfangbaren digitalen Rundfunkwellensignalen entsprechen, deren Empfangsstärken
den vorbestimmten Wert überschreiten, mit Ausnahme von Kanälen, die digitalen Rundfunkwellensignalen
entsprechen, deren Gebietscodes mit dem Gebietscode des momentan empfangenen digitalen
Rundfunkwellensignals zusammenfallen, wenn die Empfangsstärkenbestimmungseinrichtung
(11) bestimmt, dass die Empfangsstärke der vorbestimmte Wert oder niedriger geworden
ist; und
eine Voreinstellaktualisierungseinrichtung (13), die dazu ausgelegt ist, Aktualisierungen
durchzuführen und die von der Abtastverarbeitungseinrichtung (12) erzeugte Liste empfangbarer
Kanäle in einem Voreinstellspeicher (10) zu speichern.
2. Digitale Rundfunkempfangsvorrichtung nach Anspruch 1, wobei das digitale Rundfunkwellensignal
ein digitales Rundfunkwellensignal ist, das durch Verwendung eines digitalen Modulationsverfahrens,
das mindestens einer ISDB-Norm oder DAB-Norm entspricht, moduliert wird.
3. Digitale Rundfunkempfangsvorrichtung nach Anspruch 1 oder 2,
wobei die Empfangsstärkenbestimmungseinrichtung (11) dazu ausgelegt ist, zu bestimmen,
ob eine Empfangsstärke des momentan empfangenen digitalen Rundfunkwellensignals der
vorbestimmte Wert oder niedriger geworden ist, und wenn die Empfangsstärkenbestimmungseinrichtung
(11) bestimmt, dass die Empfangsstärke der vorbestimmte Wert oder niedriger geworden
ist, die Empfangsstärkenbestimmungseinrichtung (11) dazu ausgelegt ist, ferner zu
bestimmen, ob von momentan in dem Voreinstellspeicher (10) gespeicherten Kanälen Empfangsstärken
von digitalen Rundfunkwellensignalen, die Kanälen entsprechen, deren Gebietscodes
mit dem Gebietscode des digitalen Rundfunkwellensignals zusammenfallen, das dem momentan
empfangenen Kanal entspricht, der vorbestimmte Wert oder niedriger geworden sind,
und
wobei, wenn die Empfangsstärkenbestimmungseinrichtung (11) bestimmt, dass die Empfangsstärke
des digitalen Rundfunkwellensignals, das dem momentan empfangenen Kanal entspricht,
und Empfangsstärken eines vorbestimmten Anteils oder mehr der digitalen Rundfunkwellensignale,
die den Kanälen entsprechen, deren Gebietscodes mit dem Gebietscode des digitalen
Rundfunkwellensignals, das dem momentan empfangenen Kanal entspricht, zusammenfallen,
der vorbestimmte Wert oder niedriger geworden sind, die Abtastverarbeitungseinrichtung
(12) dazu ausgelegt ist, die Empfangsfrequenz des Tuners (2) zu ändern und eine Liste
empfangbarer Kanäle von den empfangbaren digitalen Rundfunkwellensignalen, deren Empfangsstärken
den vorbestimmten Wert übersteigen, zu erzeugen.
4. Digitale Rundfunkempfangsvorrichtung nach einem der Ansprüche 1-3, wobei die Voreinstellaktualisierungseinrichtung
(13) dazu ausgelegt ist, in dem Voreinstellspeicher (10) von den von der Abtastverarbeitungseinrichtung
(12) extrahierten empfangbaren Kanälen nur Kanäle zu speichern, die digitalen Rundfunkwellensignalen
mit einem am häufigsten extrahierten Gebietscode entsprechen.
5. Verfahren zum Empfangen eines digitalen Rundfunkwellensignals, das umfasst:
einen ersten Schritt des Bestimmens, ob eine Empfangsstärke eines digitalen Rundfunkwellensignals,
das einem momentan von einem Tuner (2) empfangenen Kanal entspricht, ein vorbestimmter
Wert oder niedriger geworden ist, wobei das digitale Rundfunkwellensignal einen Gebietscode
umfasst, der ein Gebiet darstellt, in dem die Rundfunkwelle empfangen werden kann;
einen zweiten Schritt des Änderns der Empfangsfrequenz des Tuners (2) und des Erzeugens
einer Liste empfangbarer Kanäle von den empfangbaren digitalen Rundfunkwellensignalen,
deren Empfangsstärken den vorbestimmten Wert überschreiten, mit Ausnahme von Kanälen,
die digitalen Rundfunkwellensignalen entsprechen, deren Gebietscodes mit einem Gebietscode
des momentan empfangenen digitalen Rundfunkwellensignals zusammenfallen, wenn bestimmt
wird, dass die Empfangsstärke der vorbestimmte Wert oder niedriger geworden ist; und
einen dritten Schritt des Durchführens von Aktualisieren und Speichern der erzeugten
Liste empfangbarer Kanäle in einem Voreinstellspeicher (10).
6. Verfahren nach Anspruch 5, wobei das digitale Rundfunkwellensignal ein digitales Rundfunkwellensignal
ist, das durch Verwendung eines digitalen Modulationsverfahrens, das mindestens einer
ISDB-Norm oder DAB-Norm entspricht, moduliert wird.
7. Verfahren nach Anspruch 5 oder 6,
wobei der erste Schritt ferner einen Schritt umfasst, in dem, wenn bestimmt wird,
dass die Empfangsstärke des digitalen Rundfunkwellensignals, das dem momentan empfangenen
Kanal entspricht, der vorbestimmte Wert oder niedriger geworden ist, ferner bestimmt
wird, ob von den momentan in dem Voreinstellspeicher (10) gespeicherten Kanälen die
Empfangsstärken der digitalen Rundfunkwellensignale, die den Kanälen entsprechen,
deren Gebietscodes mit dem Gebietscode des momentan empfangenen Kanals zusammenfallen,
der vorbestimmte Wert oder niedriger geworden sind, und
wobei der zweite Schritt ferner einen Schritt umfasst, in dem, wenn bestimmt wird,
dass die Empfangsstärke des digitalen Rundfunkwellensignals, das dem momentan empfangenen
Kanal entspricht, und die Empfangsstärken eines vorbestimmten Anteils oder mehr der
digitalen Rundfunkwellensignale, die den Kanälen entsprechen, deren Gebietscodes mit
dem Gebietscode des digitalen Rundfunkwellensignals, das dem momentan empfangenen
Kanal entspricht, zusammenfallen, der vorbestimmte Wert oder niedriger geworden sind,
die Empfangsfrequenz des Tuners (2) geändert wird und eine Liste empfangbarer Kanäle
von den empfangbaren digitalen Rundfunkwellensignalen, deren Empfangsstärken den vorbestimmten
Wert übersteigen, erzeugt wird.
8. Verfahren nach einem der Ansprüche 5-7, wobei der dritte Schritt ferner einen Schritt
des Speicherns, in dem Voreinstellspeicher (10), nur von Kanälen, die digitalen Rundfunkwellensignalen
mit einem am häufigsten extrahierten Gebietscode entsprechen, von den durch das Abtasten
extrahierten empfangbaren Kanälen umfasst.
1. Appareil de réception de diffusion numérique, comprenant :
un syntoniseur (2) configuré pour recevoir un signal d'onde de diffusion numérique
dont la fréquence de réception correspond à celle d'un canal recherché, le signal
d'onde de diffusion numérique comprenant un indicatif de zone représentant une zone
dans laquelle l'onde de diffusion du canal recherché peut être reçue ;
un moyen de détermination (11) de la puissance de réception configuré pour déterminer
le fait de savoir si oui ou non une puissance de réception du signal reçu d'onde de
diffusion numérique a pris une valeur prédéterminée ou une valeur inférieure ;
un moyen de traitement par balayage (12) configuré pour modifier la fréquence de réception
du syntoniseur (2) et pour générer une liste de canaux qui peuvent être reçus à partir
des canaux correspondant à des signaux d'ondes de diffusion numérique aptes à être
reçus, dont les puissances de réception dépassent la valeur prédéterminée, à l'exception
de canaux correspondant à des signaux d'ondes de diffusion numérique dont les indicatifs
de zones coïncident avec l'indicatif de zone du signal d'onde de diffusion numérique
en train d'être reçu, lorsque le moyen de détermination (11) de la puissance de réception
détermine que la puissance de réception a pris la valeur prédéterminée ou une valeur
inférieure ; et
un moyen de mise à jour préétabli (13) configuré pour procéder à une mise à jour et
pour mémoriser la liste de canaux qui peuvent être reçus, générée par le moyen de
traitement par balayage (12), dans une mémoire préétablie (10).
2. Appareil de réception de diffusion numérique selon la revendication 1, dans lequel
le signal d'onde de diffusion numérique est un signal d'onde de diffusion numérique
modulé en utilisant un procédé de modulation numérique conforme à au moins une norme
choisie parmi une norme ISDB ou une norme DAB.
3. Appareil de réception de diffusion numérique selon la revendication 1 ou 2, dans lequel
le moyen de détermination (11) de la puissance de réception est configuré pour déterminer
le fait de savoir si oui ou non une puissance de réception du signal d'onde de diffusion
numérique en train d'être reçu a pris la valeur prédéterminée ou une valeur inférieure,
et lorsque le moyen de détermination (11) de la puissance de réception détermine que
la puissance de réception a pris la valeur prédéterminée ou une valeur inférieure,
le moyen de détermination (11) de la puissance de réception est en outre configuré
pour déterminer le fait de savoir si oui ou non, parmi les canaux présentement mis
en mémoire dans la mémoire préétablie (10), des puissances de réception de signaux
d'ondes de diffusion numérique correspondant à des canaux dont les indicatifs de zones
coïncident avec l'indicatif de zone du signal d'onde de diffusion numérique correspondant
au canal en train d'être reçu ont pris la valeur prédéterminée ou une valeur inférieure
; et
dans lequel, lorsque le moyen de détermination (11) de la puissance de réception détermine
que la puissance de réception du signal d'onde de diffusion numérique correspondant
au canal en train d'être reçu et que des puissances de réception d'une proportion
prédéterminée ou plus des signaux d'ondes de diffusion numérique correspondant aux
canaux dont les indicatifs de zones coïncident avec l'indicatif de zone du signal
d'onde de diffusion numérique correspondant au canal en train d'être reçu ont pris
la valeur prédéterminée ou une valeur inférieure, le moyen de traitement par balayage
(12) est configuré pour modifier la fréquence de réception du syntoniseur (2) et pour
générer une liste de canaux qui peuvent être reçus à partir des signaux d'ondes de
diffusion numérique aptes à être reçus, dont les puissances de réception dépassent
la valeur prédéterminée.
4. Appareil de réception de diffusion numérique selon l'une quelconque des revendications
1 à 3, dans lequel le moyen de mise à jour préétabli (13) est configuré pour mettre
en mémoire, dans la mémoire préétablie (10), uniquement des canaux qui correspondent
à des signaux d'ondes de diffusion numérique qui possèdent un indicatif de zone extrait
le plus fréquemment parmi les canaux qui peuvent être reçus extraits par le moyen
de traitement par balayage (12).
5. Procédé destiné à la réception d'un signal d'onde de diffusion numérique, comprenant
:
une première étape consistant à déterminer le fait de savoir si oui ou non une puissance
de réception d'un signal d'onde de diffusion numérique correspondant à un canal en
train d'être reçu par un syntoniseur (2) a pris une valeur prédéterminée ou une valeur
inférieure, le signal d'onde de diffusion numérique comprenant un indicatif de zone
représentant une zone dans laquelle l'onde de diffusion peut être reçue ;
une deuxième étape consistant à modifier la fréquence de réception du syntoniseur
(2) et à générer une liste de canaux qui peuvent être reçus à partir des signaux d'ondes
de diffusion numérique aptes à être reçus, dont les puissances de réception dépassent
la valeur prédéterminée, à l'exception de canaux correspondant à des signaux d'ondes
de diffusion numérique dont les indicatifs de zones coïncident avec un indicatif de
zone du signal d'onde de diffusion numérique en train d'être reçu, lorsqu'il est déterminé
que la puissance de réception a pris la valeur prédéterminée ou une valeur inférieure
; et
une troisième étape consistant à procéder à une mise à jour et à une mise en mémoire
de la liste générée de canaux qui peuvent être reçus, dans une mémoire préétablie
(10).
6. Procédé selon la revendication 5, dans lequel le signal d'onde de diffusion numérique
est un signal d'onde de diffusion numérique modulé en utilisant un procédé de modulation
numérique conforme à au moins une norme choisie parmi une norme ISDB ou une norme
DAB.
7. Procédé selon la revendication 5 ou 6,
dans lequel la première étape englobe en outre une étape consistant à, lorsqu'il est
déterminé que la puissance de réception du signal d'onde de diffusion numérique correspondant
au canal en train d'être reçu a pris la valeur prédéterminée ou une valeur inférieure,
déterminer en outre le fait de savoir si oui ou non, parmi les canaux présentement
mis en mémoire dans la mémoire préétablie (10), les puissances de réception des signaux
d'ondes de diffusion numérique correspondant aux canaux dont les indicatifs de zones
coïncident avec l'indicatif de zone du canal en train d'être reçu ont pris la valeur
prédéterminée ou une valeur inférieure ; et
dans lequel la deuxième étape englobe en outre une étape consistant à, lorsqu'il est
déterminé que la puissance de réception du signal d'onde de diffusion numérique correspondant
au canal en train d'être reçu et que les puissances de réception d'une proportion
prédéterminée ou plus des signaux d'ondes de diffusion numérique correspondant aux
canaux dont les indicatifs de zones coïncident avec l'indicatif de zone du signal
d'onde de diffusion numérique correspondant au canal en train d'être reçu ont pris
la valeur prédéterminée ou une valeur inférieure, modifier la fréquence de réception
du syntoniseur (2) et générer une liste de canaux qui peuvent être reçus à partir
des signaux d'ondes de diffusion numérique apte à être reçus, dont les puissances
de réception dépassent la valeur prédéterminée.
8. Procédé selon l'une quelconque des revendications 5 à 7, dans lequel la troisième
étape englobe en outre une étape consistant à mettre en mémoire, dans la mémoire préétablie
(10), uniquement des canaux qui correspondent aux signaux d'ondes de diffusion numérique
qui possèdent un indicatif de zone extrait le plus fréquemment parmi les canaux qui
peuvent être reçus, extraits par le balayage.