FIELD OF INVENTION
[0001] The present invention relates generally to antenna devices and more particularly
to an antenna device for use in a portable radio communication device providing a
diversity function.
BACKGROUND
[0002] The application of internal antennas in a mobile phone puts some constraints on the
configuration of the radiating element of the antenna. In particular, in a portable
radio communication device the space for an internal antenna device is limited. These
constraints may make it difficult to find a configuration of the antenna device that
provides for desired use.
[0003] One specific application operating in a relatively low frequency band is the FM radio
application. The FM operating band is defined as frequencies between 88-108 MHz in
most of the world and frequencies between 76-90 MHz in Japan. Prior art conventional
antenna configurations, such as loop antennas or monopole antennas, fitted within
the casing of a portable radio communication device will result in unsatisfactory
operation in that the antenna either has too bad performance over a sufficiently wide
frequency band or sufficient performance over a too narrow frequency band.
[0004] Instead, a conventional FM antenna for portable radio communication devices is usually
provided in the headset wire connected to the communication device. This configuration
with a relatively long wire permits an antenna length that is sufficient also for
low frequency applications. However, if no external antenna is permitted due to design
choices, this solution is obviously not feasible.
[0005] The interaction between antenna, telephone body and close-by environment, such as
e.g. the user himself, will become more important as the wireless terminals become
smaller and smaller. It is thus a formidable task to manufacture such compact and
versatile terminals, which exhibit good antenna performance under a variety of conditions.
[0006] Further, a portable radio communication device is today many times provided with
frequency operational coverage for other frequency bands then FM, such as GSM900,
GSM1800, GPS, BT, WLAN, WCDMA and GPS. A portable radio communication device has limited
space and it is thus desirable to, if possible, add multiple functionality to an antenna
device.
SUMMARY OF THE INVENTION
[0007] An object of the present invention is to provide an antenna device for a portable
radio communication device, which efficiently utilizes available space of the portable
radio communication device and is adaptable to varying communication environment.
[0008] This object, among others, is according to the present invention attained by an antenna
device, an antenna system and a portable radio communication device, respectively,
as defined by the appended claims.
[0009] By providing an antenna device for a portable radio communication device, wherein
the antenna device comprises an elongated radiating element, first switching means
connected between a first end of the elongated radiating element and ground, and second
switching means connected between a second end of the elongated radiating element,
opposite the first end thereof, and first filtering means and second filtering means,
wherein the first switching means is configured to connect the elongated radiating
element to ground when the second switching means is configured to connect the elongated
radiating element to the first filtering means, and the first filtering means is configured
to disconnect the elongated radiating element from ground when the second switching
means is configured to connect the elongated radiating element to the second filtering
means, an antenna device able to work as an electric resonant antenna and as a magnetic
resonant antenna with a single radiating element is provided.
[0010] Preferably the second end of the elongated radiating element is configured to be
connected to a FM receiver.
[0011] Preferably, the antenna device is further configured for simultaneous multi frequency
band operation wherein four different antennas are combined into one antenna device
providing simultaneous operation with good isolation between all antennas as well
as good performance for all antennas.
[0012] The configuration of the antenna device is preferably such that it effectively works
as a monopole antenna for BT, GPS and WCDMA Rx operating frequencies, respectively,
and as a magnetic resonant antenna for FM operating frequencies in a default mode,
and effectively work as an electric resonant monopole antenna for FM operating frequencies
in a diversity mode.
[0013] By preferably supporting the first, second and third elongated radiating elements
on a dielectric carrier a cost efficient and robust installation of the antenna device
is provided. Advantageously the dielectric carrier is part of the back cover of the
portable radio communication device.
[0014] Preferably the first, second, fifth, seventh and eighth filtering means are provided
as RF chokes, whereby good quality blocking is achieved, and the third, fourth and
sixth filtering means are preferably provided as capacitors, whereby low cost blocking
is achieved. By alternatively providing the first, second, fifth, seventh and eighth
filtering means as a simple inductances low cost blocking is achieved.
[0015] By preferably connecting the third filtering means to the second elongated radiating
element close to the second filtering means and configuring the second and third filtering
means together to block GPS operating frequencies, in order to improve isolation between
BT and GPS operation. Alternatively, the third filtering means is connected to the
second elongated radiating element close to the first filtering means and the first
and third filtering means are together configured to block GPS operating frequencies.
[0016] Further preferred embodiments are defined in the dependent claims.
BRIEF DESCRIPTION OF DRAWINGS
[0017] The present invention will become more fully understood from the detailed description
of embodiments given below and the accompanying figures, which are given by way of
illustration only, and thus, are not limitative of the present invention, wherein:
FIG. 1 is a schematic diagram showing a first embodiment of an antenna device according
to the present invention.
FIG. 2 is a schematic diagram showing a second embodiment of an antenna device of
the present invention.
FIG. 3 is a schematic diagram showing a third embodiment of an antenna device according
to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0018] In the following description, for purpose of explanation and not limitation, specific
details are set forth, such as particular techniques and applications in order to
provide a thorough understanding of the present invention. However, it will be apparent
for a person skilled in the art that the present invention may be practiced in other
embodiments that depart from these specific details. In other instances, detailed
description of well-known methods and apparatuses are omitted so as not to obscure
the description of the present invention with unnecessary details.
[0019] In the following description and claims, the term radiating element is used. It is
to be understood that this term is intended to cover electrically conductive elements
configured for receiving and/or transmitting radio signals. Further the term IFA type
antenna is also used, which is to be understood as a radiating element comprising
feeding and grounding points in one end thereof and the other end being open. Also,
the term loop type antenna is used, which is to be understood as an antenna having
an effective radiating structure of essentially a loop. The term a magnetic resonant
antenna is to be understood as a radiator of magnetic nature made resonant with a
matching component for FM frequencies. The term an electric resonant monopole antenna
is to be understood as a radiator of electric nature made resonant with a matching
component for FM frequencies.
[0020] An antenna device for a portable radio communication device according to a first
embodiment of the present invention will now be described with reference to Fig. 1.
[0021] The antenna device comprises an elongated radiating element 1, first switching means
2 and second switching means 3. The first switching means 2 is connected to a first
end of the elongated radiating element 1 and to ground, and the second switching means
3 is connected to a second end of the elongated radiating element 1, opposite the
first end thereof, to first filtering means 4 and to second filtering means 5.
[0022] The first filtering means 4 is connected between the second filtering means 3 and
ground. The first filtering means 4 is capacitive, and is in a simple form provided
as a capacitor of about 30 pF. The second filtering means 5 is connected between the
second filtering means 3 and ground. The second filtering means 5 is inductive, and
is in a simple form provided as an inductor of about 470 nH.
[0023] The second end of the elongated radiating element 1 is also connected to a FM receiver
6. The elongated radiating element 1 is preferably positioned over a printed wiring
board 7 of the portable radio communication device, providing a ground plane for the
elongated radiating element 1.
[0024] The elongated radiating element 1 is configured to provide a diversity function for
the FM receiver 6, working as an electric resonant monopole antenna in a first state,
diversity mode, and working as a magnetic resonant half-loop antenna in a second state,
default mode.
[0025] In the first state the first switching means 2 disconnects the first end of the elongated
radiating element 1 from ground, making the first end of the elongated radiating element
1 being open ended. In the first state the second switching means 3 connects the second
end of the elongated radiating element 1 to the second filtering means 5, which tunes
the elongated radiating element 1 to FM frequencies.
[0026] In the second state the first switching means 2 connects the first end of the elongated
radiating element 1 to ground, and the second switching means 3 connects the second
end of the elongated radiating element 1 to the first filtering means 4, which tunes
the elongated radiating element 1 to FM frequencies.
[0027] Further, a high impedance amplifier, together with associated components, such as
ESD protection components, is preferably provided between the FM receiver 6 and the
elongated radiating element 1.
[0028] The FM receiver 6 preferably selects which state to work the FM antenna in, based
on signal quality. The FM receiver 6 utilizes one or more of the following diversity
functions. A user interaction diversity, wherein a user close to or holding the portable
radio communication device affects an electric resonant monopole antenna more than
a magnetic resonant half-loop antenna. An EMI diversity, wherein EMI (electromagnetic
interference) or other environmental noise is dominated by either a electronic or
magnetic component. A pattern diversity, wherein the reception pattern is likely not
equally strong in different directions of the FM antenna. A polarization diversity,
wherein reception polarization is likely not equally strong in different polarizations
of the FM antenna.
[0029] The FM antenna and the FM receiver together make up an antenna system. The antenna
system preferably comprises a FM transceiver instead of a FM receiver, providing the
same diversity function for FM reception as with only a FM receiver. The state of
the FM antenna for FM transmission is preferably based on which state provides the
highest gain during design of the FM antenna and the portable radio communication
device.
[0030] The processing technique for the diversity function could e.g. use switching and
selecting.
[0031] An antenna device for a portable radio communication device according to a second
embodiment of the present invention will now be described with reference to Fig. 2.
[0032] The antenna device comprises a first elongated radiating element 10, a second elongated
radiating element 11, and a third elongated radiating element 12. The antenna device
further comprises first filtering means 13 connected between a first end of the first
elongated radiating element 10 and a first end of the second elongated radiating element
11, and second filtering means 14 connected between a second end of the second elongated
radiating element 11, opposite the first end thereof, and a first end of the third
elongated radiating element 12. The second radiating element 12 is connected to ground
through third filtering means 15.
[0033] A second end of the first elongated radiating element 10, opposite the first end
thereof, is connected to fourth filtering means 16, which in turn is connected to
a BT (Bluetooth) transceiver 17 and first switching means 18. The first switching
means 18 is also connected to ground through eighth filtering means 32, which serves
as a matching component for the BT transceiver.
[0034] A second end of the third elongated radiating element 12, opposite the first end
thereof, is connected to a WCDMA (Wideband Code Division Multiple Access) Rx receiver
19, preferably a diversity receiver, and a GPS receiver 20. The WCDMA receiver 19
and GPS receiver 20 are preferably connected through a WCDMA/GPS diplexer 21, which
diplex filter 21 e.g. is implemented as a standard component or integrated on chips.
Additionally, a matching network 22 is preferably provided between the diplex filter
21 and the second end of the third radiating element 12, for matching of the WCDMA
receiver 19. The matching network 22 is preferably a capacitor of about 0.5 pF.
[0035] A FM transceiver 23 is connected to fifth filtering means 24, which in turn is connected
to the first elongated radiating element 10 close to the second end thereof, and to
second switching means 25. The second switching means 25 is further connected to ground
through sixth filtering means 26 and seventh filtering means 27, respectively.
[0036] Third switching means 28 is connected between ground and the third radiating element
12 close to the second end thereof.
[0037] In a first state, default mode, of the antenna device the first switching means 18
disconnects the BT transceiver from the eighth filtering means 32, the second switching
means 25 connects the first elongated radiating element 10 to the sixth filtering
means 26, and the third filtering means 28 connects the third elongated radiating
element 12 to ground. In this way the FM receiver 23 exhibits a magnetic resonant
loop structure, and the BT, GPS and WCDMA receivers exhibit a monopole structure.
[0038] In a second state, diversity mode, of the antenna device the first switching means
18 connects the BT transceiver to the eighth filtering means 32, the second switching
means 25 connects the first elongated radiating element 10 to the seventh filtering
means 27, and the third filtering means 28 disconnects the third elongated radiating
element 12 from ground. In this way the FM receiver 23 exhibits an electric resonant
monopole structure, and the BT transceiver 17 still exhibits a monopole structure,
but the GPS receiver 20 and the WCDMA receiver 19 do no longer work in the diversity
mode.
[0039] The first, second and third elongated radiating elements 10, 11 and 12 together have
a length 29 configured for FM operation, about 110 mm. The first elongated radiating
element 10 have a length 30 configured for BT operation, about 35 mm. The length between
the connection point of the second switching means 25 on the first elongated radiating
element 10 and the second end thereof is configured for matching of the BT transceiver
19, about 10 mm. The third elongated radiating element 12 has a length 31 configured
for WCDMA Rx operation, about 35 mm. The length 32 for GPS operation is preferably
about 70 mm. The length between the connection point of the third switching means
28 on the third elongated radiating element 12 and the second end thereof is configured
for matching of the WCDMA Rx receiver 19, and is typically about 10 mm. The first
filtering means 13 and the third filtering means 15 are together configured for blocking
of GPS operation, and the length there between is about 5 mm. The exemplary lengths
given above are dependent on e.g. distance above a ground plane device 7, in this
case based on the distance of about 6 mm and filtering means values.
[0040] The first filtering means 13 is preferably provided as an RF choke, but could also
be provided as a simple inductor, of about 20 nH, and could alternatively be provided
as a parallel resonant circuit. The first filtering means 13 is in such a way configured
to pass FM operation and to block BT operation. The second filtering means 14 is preferably
provided as an RF choke, but could also be provided as a simple inductor, of about
15 nH, and could alternatively be provided as a parallel resonant circuit. The second
filtering means 14 is in such a way configured to pass FM and GPS operation and to
block WCDMA operation. The third filtering means 15 is preferably provided as a capacitor
of about 5 pF. The first and third filtering means 13 and 15 are in such a way configured
to block GPS operation.
[0041] The fourth filtering means 16 is preferably provided as a capacitor of about 1 pF.
The fourth filtering means 16 is in such a way configured to pass BT operation and
to block FM operation. The fifth filtering means 24 is preferably provided as an inductor
of about 56 nH. The fifth filtering means 24 is in such a way configured as a low
pass filter for FM frequencies, and thus blocks e.g. BT operating frequencies. The
antenna device is in such a way configured to simultaneously with FM frequencies operate
at BT, GPS and WCDMA Rx frequencies.
[0042] In the default mode the antenna device thus exhibits a ground and feed point near
the second end of the first elongated radiating element and an open end in first end
of the first elongated radiating element, for BT frequencies. In the default mode
the antenna device also exhibits a ground and feed point in the second end of the
third elongated radiating element and an open end in the combined first and third
filtering means, for GPS frequencies. In the default mode the antenna device further
exhibits a ground and feed point in the second end of the third elongated radiating
element and an open end in the second filtering means, for WCDMA frequencies. In the
default mode the antenna device also exhibits a loop structure from the fifth filtering
means to grounding near the second end of the third elongated radiating element 12,
for FM frequencies. The antenna device needs no diplexer for implementing FM frequencies.
The isolation between all antennas is good, as well as the performance of all antennas,
for such an antenna device.
[0043] The first, second and third elongated radiating elements are preferably planar elements
supported by a dielectric carrier, such as radiating portions on a dielectric flexible
film supported by a carrier. The dielectric carrier is preferably a portion of the
back cover of the portable radio communication device. Alternatively the dielectric
carrier is e.g. a portion of the middle deck the portable radio communication device.
With the first, second and third elongated radiating elements supported by a dielectric
carrier the RF choke is preferably mounted thereon. Further, the first, second and
third elongated radiating elements are alternatively self-supported, and the RF choke
is in this case preferably mounted on a printed wiring board onto which the radiating
elements are mounted on.
[0044] The antenna device preferably forms a half-loop radiating element for FM operation.
A half-loop antenna is a virtual loop antenna, by being provided over a ground plane
device 7 of the portable radio communication device. The second end of the first elongated
radiating element 10 and the second end of the third elongated radiating element 12
protrudes out of the feed and ground for the FM loop structure, but these parts are
seen as open-ended stubs protruding from a loop, by the FM transceiver, which stubs
affect FM operation very little.
[0045] The BT, GPS and WCDMA antennas utilize parts of the FM antenna, which antennas thus
are added to an originally configured active FM antenna without essentially increasing
utilization of available space in the portable radio communication device. All antennas
are preferably configured to operate on their respective ground tone, which thereby
minimizes their sensitivity to the environment.
[0046] Due to that the BT transceiver and the FM transceiver have feed points closely located
on the first elongated radiating element 10 they can be provided as a single module
combo transceiver without long transmission lines.
[0047] For configuration of the antenna device the first filtering means 13 is preferably
positioned at the voltage maxima for the BT antenna, the second filtering means 14
is preferably positioned at the voltage maxima for the WCDMA antenna, and the third
filtering means 15 is preferably positioned at the current maxima for the GPS antenna,
respectively.
[0048] An antenna system for the first embodiment of the antenna device preferably comprises
the antenna device, the switching means, the filtering means and the receivers and
transceivers.
[0049] A third embodiment of an antenna device for a portable radio communication device
according to the present invention is illustrated in Fig. 3. The main difference between
the second embodiment and the third embodiment is that the GPS receiver is connected
to the first elongated radiating element instead of the third elongated radiating
element.
[0050] The antenna device comprises a first elongated radiating element 10, a second elongated
radiating element 11, and a third elongated radiating element 12. The antenna device
further comprises first filtering means 13 connected between a first end of the first
elongated radiating element 10 and a first end of the second elongated radiating element
11, and second filtering means 14 connected between a second end of the second elongated
radiating element 11, opposite the first end thereof, and a first end of the third
elongated radiating element 12. The second radiating element 12 is connected to ground
through third filtering means 15.
[0051] A second end of the first elongated radiating element 10, opposite the first end
thereof, is connected to fourth filtering means 16, which in turn is connected to
a BT (Bluetooth) transceiver 17, a GPS receiver 20, preferably connected through a
BT/GPS diplexer 33, and first switching means 18. The first switching means 18 is
also connected to ground through eighth filtering means 32. The diplex filter 33 is
e.g. implemented as a standard component or integrated on chips.
[0052] A second end of the third elongated radiating element 12, opposite the first end
thereof, is connected to a WCDMA (Wideband Code Division Multiple Access) Rx receiver
19, preferably a diversity receiver, Additionally, a matching network 22 is preferably
provided between the WCDMA receiver 19 and the second end of the third radiating element
12, for matching of the WCDMA receiver 19. The matching network 22 is preferably a
capacitor of about 0.5 pF.
[0053] A FM transceiver 23 is connected to fifth filtering means 24, which in turn is connected
to the first elongated radiating element 10 close to the second end thereof, and to
second switching means 25. The second switching means 25 is further connected to ground
through sixth filtering means 26 and seventh filtering means 27, respectively.
[0054] Third switching means 28 is connected between ground and the third radiating element
12 close to the second end thereof.
[0055] In a first state, default mode, of the antenna device the first switching means 18
disconnects the fourth filtering means 16 from the eighth filtering means 32, the
second switching means 25 connects the first elongated radiating element 10 to the
sixth filtering means 26, and the third filtering means 28 connects the third elongated
radiating element 12 to ground. In this way the FM receiver 23 exhibits a magnetic
resonant loop structure, and the BT, GPS and WCDMA receivers exhibit an monopole structure.
[0056] In a second state, diversity mode, of the antenna device the first switching means
18 connects the fourth filtering means 16 to the eighth filtering means 32, the second
switching means 25 connects the first elongated radiating element 10 to the seventh
filtering means 27, and the third filtering means 28 disconnects the third elongated
radiating element 12 from ground. In this way the FM receiver 23 exhibits an electric
resonant monopole structure, and the BT transceiver 17 still exhibits a monopole structure,
but the GPS receiver 20 and the WCDMA receiver 19 do no longer work in the diversity
mode.
[0057] The first, second and third elongated radiating elements 10, 11 and 12 together have
a length 29 configured for FM operation, about 110 mm. The first elongated radiating
element 10 have a length 30 configured for BT operation, about 35 mm. The length between
the connection point of the second switching means 25 on the first elongated radiating
element 10 and the second end thereof is configured for matching of the BT transceiver
19, about 10 mm. The third elongated radiating element 12 has a length 31 configured
for WCDMA Rx operation, about 35 mm. The length 32 for GPS operation is preferably
about 70 mm. The length between the connection point of the third switching means
28 on the third elongated radiating element 12 and the second end thereof is configured
for matching of the WCDMA Rx receiver 19, and is typically about 10 mm. The second
filtering means 13 and the third filtering means 15 are together configured for blocking
of GPS operation, and the length there between is about 5 mm. The exemplary lengths
given above are dependent on e.g. distance above a ground plane device 7, in this
case based on the distance of about 6 mm and filtering means values.
[0058] The first filtering means 13 is preferably provided as an RF choke, but could also
be provided as a simple inductor, of about 20 nH, and could alternatively be provided
as a parallel resonant circuit. The first filtering means 13 is in such a way configured
to pass FM and GPS operation and to block BT operation. The second filtering means
14 is preferably provided as an RF choke, but could also be provided as a simple inductor,
of about 15 nH, and could alternatively be provided as a parallel resonant circuit.
The second filtering means 14 is in such a way configured to pass FM operation and
to block WCDMA operation. The third filtering means 15 is preferably provided as a
capacitor of about 5 pF. The second and third filtering means 13 and 15 are in such
a way configured to block GPS operation.
[0059] The fourth filtering means 16 is preferably provided as a capacitor of about 1 pF.
The fourth filtering means 16 is in such a way configured to pass BT operation and
to block FM operation. The fifth filtering means 24 is preferably provided as an inductor
of about 56 nH. The fifth filtering means 24 is in such a way configured as a low
pass filter for FM frequencies, and thus blocks e.g. BT operating frequencies. The
antenna device is in such a way configured to simultaneously with FM frequencies operate
at BT, GPS and WCDMA Rx frequencies.
[0060] Due to that the BT transceiver, the FM transceiver and the GPS receiver have feed
points closely located on the first elongated radiating element 10 they can be provided
as a single module combo transceiver without long transmission lines.
[0061] For configuration of the antenna device the first filtering means 13 is preferably
positioned at the voltage maxima for the BT antenna, the second filtering means 14
is preferably positioned at the voltage maxima for the WCDMA antenna, and the third
filtering means 15 is preferably positioned at the current maxima for the GPS antenna,
respectively.
[0062] It will be obvious that the present invention may be varied in a plurality of ways.
Such variations are not to be regarded as departure from the scope of the present
invention as defined by the appended claims. All such variations as would be obvious
for a person skilled in the art are intended to be included within the scope of the
present invention as defined by the appended claims.
1. An antenna device for a portable radio communication device, characterized in that
said antenna device comprises an elongated radiating element (1), first switching
means (2) connected between a first end of said elongated radiating element and ground,
and second switching means (3) connected between a second end of said elongated radiating
element, opposite said first end thereof, and first filtering means (4) and second
filtering means (5),
wherein said first switching means (2) is configured to be connected to ground when
said second switching means (3) is connected to said first filtering means (4), and
said first filtering means (2) is configured to be disconnected from ground when said
second switching means (3) is connected to said second filtering means (5).
2. The antenna device according to claim 1, wherein said second end of said elongated
radiating element (1) is configured to be connected to a FM receiver.
3. The antenna device according to claim 1 or 2,
wherein said first filtering means (4) is capacitive and said second filtering means
(5) is inductive.
4. An antenna device for a portable radio communication device, characterized in that
said antenna device comprises an elongated radiating element (1) configured to, in
a first state, work as an electric resonant monopole antenna and to, in a second state,
work as a magnetic resonant half-loop antenna.
5. The antenna device according to claim 4, wherein said elongated radiating element
(1) is configured to provide diversity function for FM reception.
6. The antenna device according to claim 5, wherein said elongated radiating element
(1) is configured to provide diversity function for BT reception.
7. The antenna device according to any of claims 4-6, comprising first switching means
(2) connected between a first end of said elongated radiating element and ground,
and second switching means (3) connected between a second end of said elongated radiating
element, opposite said first end thereof, and first filtering means (4) and second
filtering means (5),
wherein said first switching means (2) is configured to be connected to ground when
said second switching means (3) is connected to said first filtering means (4), and
said first filtering means (2) is configured to be disconnected from ground when said
second switching means (3) is connected to said second filtering means (5).
8. The antenna device according to any of claims 4-7,
wherein said first filtering means (4) is capacitive and said second filtering means
(5) is inductive.
9. An antenna device for a portable radio communication device, characterized in that
said antenna device comprises a first elongated radiating element (10), a second elongated
radiating element (11), a third elongated radiating element (12), first filtering
means (13), second filtering means (14), third filtering means (15), fourth filtering
means (16), fifth filtering means (24), sixth filtering means (26), seventh filtering
means (27), eighth filtering means (32), first switching means (18), second switching
means (25), and third switching means (28),
wherein said first filtering means (13) is connected between a first end of said first
elongated radiating element (10) and a first end of said second elongated radiating
element (11), said second filtering means (14) is connected between a second end of
said second elongated radiating element (11), opposite the first end thereof, and
a first end of said third elongated radiating element (12), said third filtering means
(14) is connected between said second elongated radiating element (11) and ground,
said fourth filtering means (16) is connected between a second end of said first elongated
radiating element (10), opposite the first end thereof, and said first switching means
(18), said fifth filtering means (24) is connected to said first elongated radiating
element (10) and to said second switching means (25), said sixth filtering means (26)
is connected between said second switching means (25) and ground, said seventh filtering
means (27) is connected between said second filtering means (25) and ground, said
eighth filtering means (32) is connected between said first switching means (18) and
ground, said third switching means (28) is connected between said third elongated
radiating element (12) and ground, and
wherein, in a first state, said first switching means (18) is configured to disconnect
said fourth filtering means (16) from said eighth filtering means (32), said second
switching means (25) is configured to connect said first elongated radiating element
(10) to said sixth filtering means (26), and said third switching means (28) is configure
to connect said third filtering means (12) to ground and in a second state said first
switching means (18) is configured to connect said fourth filtering means (16) to
said eighth filtering means (32), said second switching means (25) is configured to
connect said first elongated radiating element (10) to said seventh filtering means
(27), and said third switching means (28) is configure to disconnect said third filtering
means (12) from ground.
10. The antenna device according to claim 9, wherein said first and second filtering means
(13, 14) each is a RF choke.
11. The antenna device according to claim 10, wherein said third filtering means (15)
is connected to said second elongated radiating element (11) close to said second
filtering means (14) and said second and third filtering means (14, 15) are together
configured to block GPS operating frequencies.
12. The antenna device according to claim 10, wherein said third filtering means (115)
is connected to said second elongated radiating element (11) close to said first filtering
means (13) and said first and third filtering means (13, 15) are together configured
to block GPS operating frequencies.
13. An antenna system for a portable radio communication device characterized in that it comprises an antenna device according to any previous claim and a FM receiver.
14. A portable radio communication device, characterized in that it comprises an antenna system according to claim 13, and a ground plane device (7),
wherein said elongated radiating elements are arranged over said ground plane device.