JP3348506B2 - Telephone / GPS common plane antenna and telephone / GPS common transmitting / receiving device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a planar antenna which can be used for both telephone and GPS, and a telephone / GPS common transmitting / receiving apparatus using the common planar antenna.

[0002]

2. Description of the Related Art Planar antennas for automobile telephones embedded in a roof of a vehicle are known (for example, see IEICE AP87-98, "Embedded planar antenna for automobile telephones", Kondo et al.). This planar antenna is a vertically polarized antenna in which a circular patch is provided on a ground plane serving as a ground pole with a short pin for impedance matching interposed therebetween, and a center pin of a coaxial cable penetrating the ground plane has a circular patch. It is connected to the center and supplied with power, and is excited in the axis symmetric mode to transmit or receive vertically polarized radio waves horizontally between the patch and the ground plane.

There is also known a planar antenna for a telephone which enables a plurality of receiving systems by independently supplying power to the respective antennas of a planar diversity antenna for a mobile telephone (for example, the Electronic Information Communication System of 1990). The National Conference of the Fall Society, "How to Feed Multifunctional Diversity Antennas," Iwashita et al.). In this planar antenna, a patch is installed on a ground plane via a short pin, similarly to the planar antenna. The patch is formed from a double-sided board. A vertically polarized antenna is formed by the board on the lower surface of the patch facing the ground plate and the ground plate, and another antenna is formed by forming an antenna pattern on the upper surface of the patch. The vertically polarized antenna is fed to the substrate on the lower surface of the patch, and the antenna on the upper surface of the patch is fed through the short pin so that each antenna operates separately.

On the other hand, GPS (Global
Navigation systems that receive the signal waves of the Positioning System (Positioning System) and measure the current position of the vehicle have been put to practical use and are widely used. The GPS receiving antenna is a planar antenna, and is a circularly polarized antenna capable of receiving a circularly polarized wave from above perpendicular to the patch in order to receive a signal radio wave from a satellite.

[0005]

By the way, if a space diversity is constituted by using two planar antennas for a telephone and a GPS receiver is to be installed, a total of three antennas is required.
One antenna must be installed on the roof of the vehicle, for example, and there is a problem that the installation space of the antenna becomes too large. Since both the antenna for the mobile phone and the antenna for the GPS are similar planar antennas, if they are shared, the installation space can be saved.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a planar antenna which can be used for both telephone and GPS, and a telephone / GPS common transmitting / receiving apparatus using the shared planar antenna.

[0007]

The invention according to claims 1 and 2 will be described with reference to FIGS. 1 and 2 showing an embodiment. The invention according to claim 1 is based on the base plate 1 and the base plate 1. This is a telephone / GPS shared planar antenna provided with a substantially circular patch 3 of conductors 3a and 3b provided in parallel with the ground plate 1 with a plurality of short pins 2a to 2d interposed therebetween. The patch 3 has a first feeding point at the center of the first surface (3a) facing the main plate 1,
The second and third power supply points are located on the circumference of a predetermined radius from the center of the second surface (3b) on the opposite side of the second surface and at a central angle of 90 degrees, and the plurality of short pins 2a to 2d is provided at a position at a central angle of 90 degrees on the circumference of a predetermined radius from the center of the patch 3, and passes through the adjacent two short pins 2c and 2d among the plurality of short pins 2a to 2d.
And the third feeding point, and the first feeding point, thereby operating as the vertically polarized antenna 4 and the second feeding point.
The antenna operates as a circularly polarized antenna 5 by feeding signals having phases different from each other by 90 degrees to the third feeding point. According to a second aspect of the present invention, there is provided a telephone / GPS shared transmitting / receiving apparatus using the telephone / GPS shared planar antenna according to the first aspect, wherein the transmitting / receiving apparatus is connected to the second and third feeding points and is 90 degrees from an input signal. And a phase circuit 11 for generating two signals having a phase difference of: and a telephone transceiver connected to a first feeding point when transmitting and receiving a telephone, and a GPS receiver connected via a phase circuit 11 when receiving a GPS signal. And a switching circuit 10 connected to the second and third feeding points. One embodiment will be described with reference to FIG. 3 to describe the invention of claim 3 and claim 4. The invention of claim 3 is directed to a telephone / telephone using two telephone / GPS common planar antennas according to claim 1. A GPS shared transmitting / receiving apparatus, which is connected to second and third feeding points of a first planar antenna 9a, and generates a first phase circuit 11a that generates two signals having a phase difference of 90 degrees from an input signal. A second phase circuit 11b connected to the second and third feeding points of the second planar antenna 9b and generating two signals having a phase difference of 90 degrees from the input signal; 2 planar antennas 9a, 9b
And a comparison circuit 14a for comparing the signal level received at the first feed point of the first and the telephone transceiver 12, usually connected to the first feed point of the first planar antenna 9a,
The GPS receiver 13 is connected to the second phase circuit 11b via the second phase circuit 11b.
Of the planar antenna (9a or 9b) having a higher signal level as a result of comparison by the comparison circuit 14a when receiving a telephone call. The telephone transceiver 12 is connected to the point, and the planar antenna (9a
Or 9b) switching circuits 10a, 10b, 14 for connecting the GPS receiver 13 to the second and third feeding points via the first or second phase circuit (11a or 11b).
a, 14b. According to a fourth aspect of the present invention, there is provided a telephone / GPS common transmitting / receiving apparatus using two telephone / GPS common planar antennas according to the first aspect, wherein the first vertically polarized antenna 4a is provided by switching a feeding point. Alternatively, a first planar antenna 9a operating as the first circularly polarized antenna 5a and two planar antennas 9a connected to the feed point of the first circularly polarized antenna 5a and having a phase difference of 90 degrees from the input signal. A first phase circuit 11a for generating a signal is connected to a feed point of a first vertically polarized antenna 4a, or
First circularly polarized antenna 5a via the phase circuit 11a of FIG.
A first feeding point switching circuit 10a for switching whether or not to connect to a second feeding point;
And a second planar antenna 9b operating as the vertically polarized antenna 4b or the second circularly polarized antenna 5b, and a feed point of the second circularly polarized antenna 5b, and 90 degrees from the input signal. A second phase circuit 11b for generating two signals having a phase difference of
Power supply point switching circuit 10b for switching between connection to the power supply point of the second antenna or connection to the power supply point of the second circularly polarized antenna 5b via the second phase circuit 11b; and a telephone transceiver. A telephone antenna switching circuit 1 for switching whether to connect the power supply 12 to a first power supply point switching circuit 10a or to a second power supply point switching circuit 10b
4a, a GPS antenna switching circuit 14b for switching whether the GPS receiver 13 is connected to the first feeding point switching circuit 10a or to the second feeding point switching circuit 10b, and a first and a second antenna switching circuit 14b. Planar antenna 9
a and a comparison circuit 14a for comparing the signal levels received by the vertical polarization antennas 4a and 4b, respectively.
Normally, the telephone transceiver 12 is transmitted via the telephone antenna switching circuit 14a and the first feeding point switching circuit 10a.
Is connected to the feed point of the first vertically polarized antenna 4a, and the GPS receiver 13 is connected to the second antenna via the GPS antenna switching circuit 14b, the second feed point switching circuit 10b, and the second phase circuit 11b. 2 circularly polarized antenna 5b
When receiving a telephone call, the result of the comparison by the comparison circuit 14a indicates that the feed point of the vertical polarization antenna (4a or 4b) of the planar antenna (9a or 9b) having the higher signal level is determined. , Telephone antenna switching circuit 14a
And a telephone transmitter / receiver 12 via the first or second feed point switching circuit (10a or 10b), and a circularly polarized antenna of the planar antenna (9a or 9b) having a lower signal level. (5a or 5b) to the feeding point via the GPS antenna switching circuit 14a, the first or second feeding point switching circuit (10a or 10b), and the first or second phase circuit (11a or 11b). The GPS receiver 13 is connected.

[0008]

A vertically polarized antenna for a mobile phone and a circularly polarized antenna for a GPS are incorporated into a planar antenna having a single structure, and the feed points are switched to form a vertically polarized antenna or a circularly polarized antenna. Make it work. As a result, a flat antenna with a single structure can be used for car phones and GPs.
The antenna can be shared with the antenna for S, so that the installation space for the antenna can be reduced and the cost can be reduced. Further, power is supplied to the second and third feeding points of the circularly polarized antenna through two adjacent short pins among a plurality of short pins provided between the ground plane and the patch. Thereby, a simple and rational antenna structure can be obtained. A planar antenna with a single structure incorporating a vertically polarized antenna and a circularly polarized antenna is used for a mobile phone by connecting a telephone transceiver to the vertically polarized antenna when transmitting and receiving a telephone, At the time of GPS reception, the GPS receiver is connected to a circularly polarized antenna via a phase circuit and used for GPS. As a result, it is possible to perform a telephone call and receive a GPS signal using a single planar antenna, and it is possible to reduce the installation space and cost of the antenna. A space diversity antenna is configured by using two planar antennas each having a single structure in which a vertically polarized antenna and a circularly polarized antenna are incorporated,
Usually, a telephone transmitter / receiver is connected to the vertical polarization antenna of one of the planar antennas and used for an automobile telephone, and the GPS receiver is connected to the circular polarization antenna of the other planar antenna via a phase circuit. Connect a device and use it for GPS. When receiving a telephone call, a planar antenna having a higher high-frequency level of radio waves received by both vertically polarized antennas is used for a mobile phone, and the other is used for a GPS.
As a result, it is possible to reduce the effect of fading in the car phone, to enable good communication, and to receive the GPS signal with either of the two antennas, so that the car phone and the GPS receiver are installed in the vehicle. However, the antenna installation space can be reduced, and the cost can be reduced.

In the means and means for solving the above problems which explain the constitution of the present invention, the drawings of the embodiments are used to make the present invention easy to understand. However, the present invention is not limited to this.

[0010]

FIG. 1 is a perspective view showing an antenna unit according to one embodiment.
FIG. 2 is a side view of the antenna portion shown in FIG.
A circular patch 3 as an antenna element is placed on a ground plate 1 serving as a ground pole with four short pins 2a to 2d for impedance matching therebetween. Both surfaces of the patch 3 are formed on a metal surface, and the lower metal surface 3 facing the main plate 1 is formed.
a and the ground plane 1 constitute a vertically polarized planar antenna 4, and the upper metal surface 3 b of the patch 3 and the ground plane 1 constitute a circularly polarized planar antenna 5. The short pins 2a to 2d are provided at positions at a central angle of 90 degrees on the circumference of the radius r from the center of the patch 3. The center pin 6a of the coaxial cable 6 is located at the center of the lower metal surface 3a of the patch 3.
And feeds power to the vertically polarized antenna 4 via the coaxial cable 6. On the other hand, the inside of the short pins 2c and 2d is passed through the coaxial cables 7 and 8 from the base plate 1 side, respectively.
The center pins 7a and 8a of the coaxial cables 7 and 8 are connected to the upper metal surface 3b of the patch 3, and power is supplied to the circularly polarized antenna 5 via these two coaxial cables 7 and 8. The feed point is switched by the feed point switch 10 to the vertically polarized antenna 4 and the circularly polarized antenna 5, and the circularly polarized antenna 5 is further fed through the circularly polarized wave excitation phase shifter 11. The feed point switching device 10 uses a coaxial switch or the like,
The phase shifter 11 uses a 90-degree hybrid coupler or the like.

In general, the design of a microstrip antenna is performed as follows. Now, assuming that the target reception frequency is f and the permittivity between the ground plane and the patch is εr, the effective radius Ae of the antenna can be obtained by the following equation.

(Equation 1) However, the actual radius A of the patch is smaller than the effective radius Ae due to leakage of the electric field from the arc (end) of the patch. The thickness of the dielectric between the ground plane and the patch is t
Then, the radius A is obtained by the following equation.

(Equation 2) In this embodiment, if the thickness of the substrate of the patch 3 is small and the dielectric of the substrate is selected to have a low dielectric constant, the dielectric between the patch 3 and the ground plane 1 is originally air and the dielectric constant is 1 Therefore, εr is

## EQU3 ## It can be considered that εr ≒ 1. Since the frequency of the 1.5 GHz band digital telephone and the GPS are close to each other and the bandwidth of the GPS signal is only 2 MHz, according to the above microstrip antenna design formula, a patch of the same size is used for the telephone and the GPS. It is possible to share them for use.

The metal surface on the upper side of the patch may be made smaller and used as a higher frequency circularly polarized wave antenna. Further, the metal surface of the patch does not need to be a perfect circle, and if the metal surface is substantially circular, the patch itself need not be circular. Further, the ground plate 1 is formed on a double-sided substrate, and the upper metal surface facing the patch 3 is used as a ground plate for a planar antenna, and both antennas 4 and 5 are formed on the lower metal surface.
The high-frequency circuit section from the feeding point to the feeding point switch 10 may be formed as a metal pattern.

FIG. 3 is a functional block diagram showing the configuration of one embodiment. The bold line in the figure indicates a coaxial cable,
Thin lines represent control lines. In this embodiment, an example will be described in which two telephone and GPS shared planar antennas 9 each having a vertically polarized antenna 4 and a circularly polarized antenna 5 shown in FIGS. 1 and 2 are installed in a vehicle. Hereinafter, one of the two planar antennas is referred to as a main antenna 9a, and the other is referred to as a sub-antenna 9b. The telephone transceiver 12 is connected to the main antenna 9a via a level comparison / feed point switching circuit 14a, a telephone band pass filter 15a and a feed point switch 10a, and a level comparison / feed point switching circuit 14a, It is connected to the sub-antenna 9b via the band-pass filter 15b and the feed point switch 10b. On the other hand, the GPS receiver 13 is
The antenna switching circuit 14b, the GPS bandpass filter and the preamplifier 16a, and the feed point switching unit 10a are connected to the main antenna 9a via the antenna switching circuit 14b, the GPS bandpass filter and the preamplifier 16b, and the feeding point switching unit 10b. Connected to the sub-antenna 9b via the antenna.

Level comparison / feed point switching circuit 14a
Controls the above-described feeding point switching devices 10a and 10b to control the main antenna 9a and the sub-antenna 9b when the telephone is used.
Is switched. Based on the control signal from the telephone transceiver 12, the time of transmission and the time of reception of the telephone are determined. At the time of transmission, the power supply point of the main antenna 9a is switched to the power supply point of the telephone vertical polarization antenna 4a. Sub antenna 9b
Is switched to the feeding point of the GPS circularly polarized antenna 5b for GPS. On the other hand, during reception, both the feeding points of the main antenna 9a and the sub-antenna 9b are
The high-frequency signal levels are compared by switching to the feeding points a and 4b, and the higher one of the two antennas 9a and 9b is switched to the telephone and the lower one is switched to the GPS. The antenna switching circuit 14b controls the feed point switching units 10a and 10b to normally set the sub-antenna 9b for GPS, and receives an antenna switching command from the level comparison / feed point switching circuit 14a when receiving a telephone call. Main antenna 9
Switch a for GPS.

FIG. 4 is a flowchart showing an antenna switching operation according to one embodiment. The operation of the embodiment will be described with reference to this flowchart. In this example, usually
The main antenna 9a is for telephone and the sub antenna 9b is G
It is set for PS and both antennas 9
a, 9b of the radio wave received by the vertically polarized antennas 4a, 4b, which has a higher high-frequency signal level, is used for telephones,
The lower one is used for GPS. In step S1, the main antenna 9a is connected to the telephone transceiver 12, and the feeding point is switched to the vertically polarized antenna 4a.
The sub-antenna 9b is connected to the GPS receiver 13, and the feeding point is switched to the circularly polarized antenna 5b, and the process proceeds to step S2 to determine whether or not to use a telephone.
If the telephone is used, the process proceeds to step S3, and if not, the process proceeds to step S4. When the telephone is not used, in step S4, the main antenna 9a is connected to the telephone transceiver 12, and the power feeding point is connected to the vertical polarization antenna 4.
a, the sub antenna 9b is connected to the GPS receiver 13, and the feeding point is set to the circularly polarized antenna 5b.
To end the process.

On the other hand, when using a telephone, step S3
It is determined whether or not the transmission is performed. If the transmission is performed, the process returns to step S1. If the transmission is not performed, the process proceeds to step S5. Step S5
Then, it is determined whether or not it is reception. If it is reception, the process proceeds to step S6, and if not, the process returns to step S2. At the time of receiving a telephone call, in step S6, the high-frequency signal levels of radio waves received by the vertically polarized antennas 4a and 4b of the main antenna 9a and the sub-antenna 9b are compared, and the level of the main antenna 9a is compared with that of the sub-antenna 9b. If it is higher, the process proceeds to step S7, where the main antenna 9a is connected to the telephone transceiver 12, the feeding point is switched to the vertically polarized antenna 4a, the sub-antenna 9b is connected to the GPS receiver 13, and The point is switched to the circularly polarized antenna 5b, and the process returns to step S5. On the other hand, when the high-frequency signal level of the sub-antenna 9b is higher than the level of the main antenna 9a, it is determined in step S8 whether or not a call is received.
Then, the main antenna 9a is connected to the GPS receiver 13, the feed point is switched to the circularly polarized antenna 5a, the sub antenna 9b is connected to the telephone transceiver 12, and the feed point is vertically polarized. It switches to the antenna 4b for use and returns to step S5. If it is determined in step S8 that the call has not been received, the process returns to step S1.

In the above-described embodiment, a space diversity for a mobile phone is constituted by using two planar antennas each having a single structure in which a vertically polarized antenna and a circularly polarized antenna are incorporated. Although the example of sharing the GPS antenna for GPS reception has been described above, it is of course possible to use such a planar antenna alone to share the antenna for the mobile phone and the GPS.

In the configuration of the above embodiment, the vertically polarized antenna 4 is a vertically polarized antenna, the circularly polarized antenna 5 is a circularly polarized antenna, the ground plane 1 is a ground plane, and the short pins 2a to 2d Is the short pin, patch 3 is the patch,
The planar antenna 9 is a planar antenna, the phase shifter 11 is a phase circuit, the feed point switcher 10 is a switching circuit, the vertical polarization antennas 4a and 4b are the first and second vertical polarization antennas, Circularly polarized antennas 5a and 5b
Compares the first and second circularly polarized antennas, the planar antennas 9a and 9b compare the first and second planar antennas, and the phase shifters 11a and 11b compare the first and second phase circuits. The feeding point switching circuit 14a is a comparison circuit, the feeding point switching units 10a and 10b, the level comparison / feeding point switching circuit 14a and the antenna switching circuit 14b are switching circuits, and the feeding point switchers 10a and 10b are first and second. Power supply point switching circuit,
The level comparison / feed point switching circuit 14a is a telephone antenna switching circuit, and the antenna switching circuit 14b is a GP.
The antenna switching circuit for S is constituted respectively.

[0019]

According to the present invention as described above, according to the present invention, and for the planar antenna of the single structure car phone GP
The antenna can be shared with the antenna for S, so that the installation space for the antenna can be reduced and the cost can be reduced. Also it is a rational antenna structure inch simple. According to the second aspect of the present invention, it is possible to perform a telephone call and a reception of a GPS signal with a single planar antenna, and it is possible to reduce the installation space and cost of the antenna. In the invention of claim 3 and claim 4,
According to this, the effect of fading in a car phone can be reduced, good communication can be performed, and a GPS signal can be received by either of two antennas. Therefore, when a car phone and a GPS receiver are installed in a vehicle, However, the antenna installation space can be reduced, and the cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view of an antenna unit according to an embodiment.

FIG. 2 is a side view of the antenna unit shown in FIG. 1;

FIG. 3 is a functional block diagram showing the configuration of one embodiment.

FIG. 4 is a flowchart showing an antenna switching operation according to one embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Ground plate 2a-2d Short pin 3 Patch 3a, 3b Metal surface 4, 4a, 4b Vertical polarization antenna 5, 5a, 5b Circular polarization antenna 6, 7, 8 Coaxial cable 6a, 7a, 8a Center pin 10, 10a, 10b Feeding point switcher 11, 11a, 11b Phaser 12 Telephone transceiver 13 GPS receiver 14a Level comparison / feeding point switching circuit 14b Antenna switching circuit 15a, 15b Telephone bandpass filter 16a, 16b GPS bandpass Filters and preamplifiers

Claims (4)

(57) [Claims] 1. A telephone / GPS common plane type comprising: a ground plate; and a substantially circular patch of a conductor provided in parallel to and opposed to the ground plate with a plurality of short pins interposed between the ground plate and the ground plate. An antenna , wherein the patch has a first feeding point at a center of a first surface facing the ground plane, and has a circle having a predetermined radius from a center of a second surface opposite to the first surface. Central angle 9 on the circumference
The second and third feeding point possess the 0 degree position, the plurality of short pins is the plant from the center of the patch
It is provided at every center angle 90 degrees on the circumference of a constant radius,
Two adjacent shorts among the plurality of short pins
Feeds the second and third feed points through a pin
Then, by feeding power to the first feeding point, the vertical polarization
The antenna operates as an antenna and communicates with the second and third feeding points.
By feeding signals that differ in phase by 90 degrees
Telephone characterized by operating as a polarization antenna /
GPS shared planar antenna. 2. A telephone / GPS common transmitting / receiving apparatus using the telephone / GPS common planar antenna according to claim 1.
Te is connected to a feeding point of the second and third, from the input signal
Phase circuit for generating two signals having a phase difference of 90 degrees
And a telephone transceiver for transmitting and receiving telephones to the first power feeding point.
Connect and connect the GPS receiver when receiving GPS signals.
The second and third feeding points are connected via the phase circuit.
And a switching circuit connected to the telephone.
GPS shared transceiver. 3. The telephone / GPS common plane according to claim 1.
Phone / GPS shared transceiver using two antennas
And the second and third feeds of the first planar antenna
2 connected to a point and having a phase difference of 90 degrees from the input signal
A first phase circuit for generating two signals, and the second and third feeds of the second planar antenna
2 connected to a point and having a phase difference of 90 degrees from the input signal
A second phase circuit for generating two signals, and the first feed of the first and second planar antennas
A comparison circuit for comparing the signal level received at a point, and usually a telephone transceiver for the first planar antenna.
Connect to the first feed point and connect the GPS receiver
The second planar antenna through the second phase circuit
Connected to the second and third feeding points of
As a result of the comparison by the comparison circuit,
The telephone to the first feeding point of one of the planar antennas
Connect the transceiver for
The second and third feed points of one of the planar antennas
To the GPS receiver via the first or second phase circuit.
A switching circuit for connecting a transceiver.
Telephone / GPS common use transceiver. 4. The telephone / GPS common plane according to claim 1.
Phone / GPS shared transceiver using two antennas
Then, by switching the feeding point, the first vertical polarization
Operating as a tenor or a first circularly polarized antenna
A first planar antenna connected to a feed point of the first circularly polarized antenna;
Generate two signals having a phase difference of 90 degrees from the signals
Connecting to a first phase circuit and a feed point of the first vertically polarized antenna,
Or for the first circularly polarized wave via the first phase circuit
First feeding for switching to connect to feeding point of antenna
A point switching circuit and a second vertical polarization amplifier by switching a feeding point.
Operating as a tena or a second circularly polarized antenna
A second planar antenna connected to a feed point of the second circularly polarized antenna;
Generate two signals having a phase difference of 90 degrees from the signals
A second phase circuit , connected to a feed point of the second vertically polarized antenna,
Or for the second circularly polarized wave via the second phase circuit
The second feed for switching whether to connect to the feed point of the antenna
A point switching circuit and a telephone transceiver connected to the first feeding point switching circuit
Or connect to the second feed point switching circuit.
A telephone antenna switching circuit for switching between a telephone and a GPS receiver to the first feed point switching circuit;
Or connect to the second feed point switching circuit
A GPS antenna switching circuit for switching between the first and second planar antennas.
Comparison circuit for comparing the signal level received by the antenna
With the door, usually, the telephone antenna switching circuit and the first
Forwards the telephone transceiver via a feed point switching circuit
Connected to the feed point of the first vertically polarized antenna.
The GPS antenna switching circuit and the second power supply.
Via a point switching circuit and the second phase circuit
GPS receiver at the feeding point of the second circularly polarized antenna
Connected, and when receiving a telephone call, as a result of comparison by the comparison circuit,
The antenna for vertical polarization of the planar antenna with the higher level
The antenna switching circuit for the telephone and the
Via the first or second feed point switching circuit.
Connect a telephone transceiver and
Feeding the circularly polarized antenna of the lower planar antenna
At this point, the GPS antenna switching circuit and the first antenna
Or the second feed point switching circuit and the first or second
A telephone / GPS shared transmission / reception device, wherein the GPS receiver is connected via a phase circuit .