JP2019050497A - Antenna device - Google Patents

Abstract

To provide an antenna device capable of reliably preventing degradation of reception characteristics without complicating the configuration of the collective antenna of multiple types of antennas.SOLUTION: An input limitation circuit 160 is branch-connected at the upstream of an amplifier 50 which may amplify mixed signals caused by wraparound, etc. of signals transmitted from two other antennas in addition to a weak signal received by an antenna 43. The input limitation circuit 160 comprises: an ON-OFF switch 161 for switching the branch-connected line to a conduction or non-conduction state; and a BPF162 configured to guide a signal transmitted from at least one of the other two antennas to a ground line. The ON-OFF switch 161 is configured to allow the line to be conductive only when both of the other antennas are transmitting a signal respectively to thereby prevent generation of the mixed signal.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an antenna device in which a plurality of types of antennas performing reception or transmission / reception of different frequency bands are collected.

  Patent Document 1 discloses a collective antenna device as an example of an on-vehicle antenna device in which a plurality of types of antennas are gathered inside a case. This collective antenna apparatus comprises an antenna for a mobile telephone network and an antenna for V2X (Vehicle to Everything) which are disposed substantially perpendicularly to a ground plane, and an antenna (patch antenna) for Global Navigation Satellite System (GNSS) parallel to the ground plane. It is an apparatus provided. The frequency band transmitted and received by the mobile phone network antenna is any one of 700 MHz band, 800 MHz band, and 900 MHz band. V2X is a wireless communication system for performing inter-vehicle communication, road-to-vehicle communication and the like, and the frequency of transmission and reception with the V2X antenna is 5850 MHz to 5925 MHz. GNSS is a global positioning satellite system, and frequencies of L1 (1575.42 MHz), L2 (1227.60 MHz), L3 (1381.05 MHz), L4 (1379.913 MHz), and L5 (1176.45 MHz) are allocated. .

Patent Document 2 also includes an antenna for LTE (Long Term Evolution) and a GPS (Global
There is disclosed an on-vehicle antenna device including a positioning system antenna. In LTE, various bands are allocated in the 2 GHz band. The application and frequency band of GPS is the same as GNSS.

JP, 2015-159354, A JP, 2013-219757, A

  One of the problems that arise when collecting multiple types of antennas that transmit and receive different frequencies as in the antenna devices disclosed in Patent Documents 1 and 2 is that each antenna in a limited space It is the influence of the electrical characteristics in each frequency band due to the optimization of the arrangement and the presence of other antennas.

  In this regard, in the antenna device disclosed in Patent Document 1, the forward radiation gain of the antenna that radiates a relatively high frequency is improved by devising the arrangement order of the antennas and the position of the feeding point. There is. Further, in Patent Document 2, a first antenna orthogonal to a reference surface (surface of a pedestal) and a second antenna disposed parallel to the reference surface are provided, and the end face of the second antenna is viewed from the side. By arranging so as to overlap with the main surface of the first antenna, an antenna device smaller than the conventional one is realized.

However, in the antenna devices disclosed in Patent Documents 1 and 2, for example, the influence on the received signals in other frequency bands when two antennas are transmitting signals (carrier signal and signal component) at the same time There is no consideration of When an amplifier for amplifying a weak reception signal is formed of a semiconductor circuit, a signal transmitted from a nearby antenna may wrap around and interfere with the original reception signal. , Can not be found in 2.
The above-mentioned situation can be avoided to some extent by providing shielding for each frequency band or connecting a filter circuit or the like in a multistage connection at the front stage of the amplifier. However, this not only complicates the configuration of the antenna device, but also causes problems such as deterioration of reception characteristics.

  An object of the present invention is, in view of the above problems, to provide an antenna apparatus that suppresses deterioration of reception characteristics without complicating a configuration when a plurality of types of antennas are gathered.

  The antenna apparatus provided by the present invention is different from a first antenna transmitting a signal of a first frequency band, a second antenna transmitting a signal of a second frequency band, and the first frequency band and the second frequency band. It is possible to amplify a mixed signal generated by mixing the signal of the first frequency band and the signal of the second frequency band in addition to the third antenna receiving the signal of the third frequency band and the signal received by the third antenna And an input limiting circuit for limiting the input of at least one of the signal of the first frequency band and the signal of the second frequency band to the amplifier.

  According to the present invention, since the input limiting circuit limits the input of at least one of the signal of the first frequency band and the signal of the second frequency band to the amplifier, the generation of mixed signals can be suppressed, which is simple. It is possible to prevent the deterioration of the reception characteristic of the amplifier for amplifying the signal of the third frequency band although it is the configuration.

(A) is a top view of the antenna apparatus of 1st Embodiment, (b) is a side view, (c) is a rear view. The external appearance perspective view which shows the structural example of an antenna part. The block diagram of the antenna part in 1st Embodiment. The other block diagram of the antenna part in 1st Embodiment. Noise figure characteristic view in a 1st embodiment. The block diagram of the antenna part in 2nd Embodiment. The block diagram of the antenna part in 3rd Embodiment. The noise figure characteristic chart which becomes a comparative example of a 2nd embodiment and a 3rd embodiment. The block diagram of the antenna part in 4th Embodiment. The block diagram of the antenna part in 5th Embodiment.

  Hereinafter, an embodiment in which the present invention is applied to a low-profile antenna device attached to a vehicle roof will be described. This antenna device is a collection of multiple types of antennas. In the following description, for the sake of convenience, the vehicle roof side is downward, vertically upward from the vehicle roof upward, the longitudinal direction of the antenna case or antenna base described later is front to back, front to back, and longitudinal The vertical direction is referred to as the left-right direction. Moreover, although the up-down direction may be expressed as the front and back, respectively, the expression similar to them may be used, but it is synonymous.

First Embodiment
1 (a) is a top view of the antenna device 1 according to the first embodiment, FIG. 1 (b) is a side view, and FIG. 1 (c) is a rear view. The antenna device 1 of the present embodiment has a case portion in which a storage space is formed, and an antenna portion stored in the storage space. The case portion has an antenna case 10 made of synthetic resin, which is a radio wave transmitting member having an opening surface portion on the lower surface side, an antenna base 20 on which the antenna case 10 is fitted, that is, the opening surface portion of the antenna case 10 While attaching the apparatus 1 to a vehicle roof, the capture part 30 for taking a ground (grounding) is provided.

  The antenna case 10 is formed in a streamlined shape which becomes thinner and lower toward the front (toward the tip) and has a curved side curved inwardly (toward the central longitudinal axis). The antenna case 10 and the antenna base 20 on which the antenna case 10 is fitted are formed in a shape conforming to the shape of the mounting surface of the vehicle roof (not shown) (the bottom of the portion on the vehicle roof side to which the antenna device 1 is attached, the same applies hereinafter) .

  An example of the structure of the antenna unit is shown in FIG. FIG. 2 is an external perspective view of the storage space with the antenna case 10 removed. In the present embodiment, the antenna unit is attached to the top of the antenna base 20. The antenna unit includes a first antenna 41, a second antenna 42, and a third antenna 43. The first antenna 41 is an antenna that transmits and receives signals in the V2X frequency band (first frequency band), and is formed in a planar shape, for example, by pattern-printing a metal member on a dielectric plate. The first antenna 41 is erected on a first substrate 411 fixed to the upper surface of the antenna base 20. The second antenna 42 is a planar antenna that transmits and receives signals in the frequency band (second frequency band) of any band of LTE, and is erected on a second substrate 421 fixed on the upper surface of the antenna base 20. Ru. The first antenna 41 may be a single tin-plated steel plate whose upper edge corresponds to the shape of the inner wall of the top portion of the antenna case 10. Although the second antenna 42 is a single tin-plated steel plate whose upper edge corresponds to the shape of the inner wall of the top portion of the antenna case 10, pattern-printing a metal member on the dielectric plate of the illustrated shape It may be formed into a planar shape.

  The third antenna 43 is a receiving antenna of the satellite positioning system, and is a patch antenna provided on the upper surface of the third substrate 431 disposed at a position lower than the upper edges of the first antenna 41 and the second antenna 42 is there. Although frequency bands used for communication from the satellite positioning system are various, in this embodiment, an example of GNSS communication will be described.

  Although not shown, a third electronic circuit that amplifies the GNSS signal received by the third antenna 43 is mounted on the back of the third substrate 431. In the third electronic circuit, an amplifier formed of a semiconductor circuit and an input limiting circuit are mounted together with a ground line.

  FIG. 3 is a block diagram of an amplification system of the GNSS signal, and a block circuit diagram is shown. Referring to FIG. 3, one end of the input limiting circuit 160 is branch-connected between the feeding portion of the third antenna 43 and the front stage of the amplifier 50, and the other end is connected to the ground line. The amplifier 50 is a semiconductor circuit for amplifying a signal of the third frequency band. The signal amplified by the amplifier 50 is output to a receiver (not shown) on the vehicle side through the output terminal 101. A control signal SEL is input from the receiver on the vehicle side to the input limiting circuit 160 through the input terminal 102.

The reason for providing the input limiting circuit 160 will be described in detail. The reception level of the GNSS signal at the third antenna 43 is around -100 dBm or less, which is extremely weak. Therefore, the amplification degree of the amplifier 50 which is a semiconductor circuit is designed to be quite high, and the noise factor is generally designed to approach 1 without limit.
The noise figure is the ratio of input signal (S: signal level) to noise (N: noise level), that is, the ratio of input S / N to output S / N, and the closer to 1 (0 dB), the clearer the signal Is an indicator that indicates that the

  On the other hand, the transmission signals from the first antenna 41 and the second antenna 42 which are close to the third antenna 43 and whose height is higher than that of the third antenna 43 are signals even if the frequency is different from that of the GNSS signal The level is large and affects the operation of the GNSS signal amplification system. That is, a part of the signal of the first frequency band transmitted from the first antenna 41 and a part of the signal of the second frequency band transmitted from the second antenna 42 wrap around through the third antenna 43 and the feeder thereof. It is assumed that the signal is input to the amplifier 50. Since harmonics are also present in these loop signals in addition to the use frequency, if the frequency of the mixed signal in which they are mixed in the amplifier 50 is generated in the third frequency band that the third antenna 43 receives, the third The GNSS signal in the frequency band is distorted, the noise figure of the amplifier 50 is significantly increased, and the GNSS reception performance of the third antenna 43 is degraded. The increase of the noise factor causes the important problem that the reception quality of the GNSS signal is degraded and the accuracy of the position measurement is degraded.

As an example, a mixed signal (1050 to 1250 MHz) of the difference between the second frequency band (4605 to 4800 MHz) of 5850 MHz of V2X which is the first frequency band and Band 40 (2300 MHz to 2400 MHz) of LTE which is the second frequency band , GNSS L2 band of the third frequency band (1197 to 1249 MHz).
In addition, a mixed signal (1563 MHz to 2220 MHz) of the difference between the frequency of V2X and the third harmonic (7488 MHz to 8070 MHz) of Band 41 (2496 MHz to 2690 MHz) of LTE, which is the second frequency band, is in the third frequency band. It occurs within the GNSS L1 band (1559 MHz to 1606 MHz). The difference between the frequency of V2X and the third harmonic (7500 MHz to 7710 MHz) of Band 7 of LTE (2500 MHz to 2570 MHz) is also the same.
In the following, it is described that a mixed signal of the frequency of the difference between the frequency of V2X and the second harmonic of Band 40 of LTE is generated in the GNSS L2 band.

  If the first antenna 41, the second antenna 42, and the third antenna 43 are shielded so as not to interfere with the other antennas, the influence of the signal can be mitigated. However, this not only complicates the configuration of the antenna device, but also causes deterioration of reception characteristics due to the shield. Therefore, it is necessary to have a mechanism for preventing the generation of the signal of the difference frequency inside the amplifier 50 without complicating the configuration of the antenna device and without deteriorating the reception characteristic. The input limiting circuit 160 is provided for that purpose.

  In the present embodiment, it is assumed that the first antenna 41 transmits and receives a V2X (5850 MHz) signal, and the second antenna 42 transmits and receives an LTE Band 40 (2300 MHz to 2400 MHz) which is the second frequency band. Further, it is assumed that the third antenna 43 receives a GNSS signal (a signal of L1 band (1559 MHz to 1606 MHz) and L2 band (1197 to 1249 MHz) of GNSS) and inputs it to the amplifier 50.

Referring to FIG. 3, the input limiting circuit 160 is configured of an open / close switch (line switch circuit) 161 which opens and closes a branch-connected line, and a BPF (band pass filter) 162. The BPF 162 minimizes (resonates) the impedance between the input and the output in the first frequency band or the second frequency band, and guides the signal of that frequency to the ground line. The BPF 162 can be configured, for example, by a series resonant circuit in which a capacitor and a coil are connected in series.
Here, it is assumed that the BPF 162 is designed to resonate at the Band 40 of LTE and to minimize its impedance.

  The open / close switch 161 conducts (closes) or does not conduct (opens) the branch-connected line in accordance with a control signal SEL sent from the receiver on the vehicle side. The on / off switch 161 conducts the line of the branch connection in a period in which both the first antenna 41 and the second antenna 42 transmit signals. During this period, the signal of Band 40 of LTE is led to the ground line through BPF 162, thereby limiting the input to amplifier 50, so that the second harmonic of Band 40 of LTE and the frequency band of V2X The mixed signal of the difference frequency of is not generated, and the occurrence of distortion when amplifying the GNSS signal in the amplifier 50 can be prevented.

  The open / close switch 161 makes the line of the branch connection nonconductive except during the above period. As a result, since the reception signal of the third antenna 43 is directly input to the amplifier 50, the loss due to the insertion of the circuit component and the deterioration of the noise factor in the amplifier 50 are avoided.

  Although FIG. 3 shows an example of the input limiting circuit 160 in which one set of the open / close switch 161 and the BPF 162 is used, two or more sets may be provided. FIG. 4 shows an example of the input limiting circuit 260 in which a set of the first open / close switch 2611 and the first BPF 2621 and a set of the second open / close switch 2612 and the second BPF 2622 are connected in parallel.

  The first BPF 2621 is designed to resonate at 5850 MHz of V2X, for example, to minimize the impedance. In addition, the second BPF 2622 is designed to resonate at Band 40 (2300 MHz to 2400 MHz) of LTE and to minimize the impedance.

  The first open / close switch 2611 conducts (closes) the line of the branch connection during transmission of the first antenna 41 and guides the signal of V2X to the ground line. Then, when the first antenna 41 is not transmitting, the line is made non-conductive (open). The open / close operation of the first open / close switch 2611 is performed based on the first control signal SEL1 input through the first input terminal 103.

  The second open / close switch 2612 conducts (closes) the branch connection line while the second antenna 42 is transmitting, and guides the signal of the LTE Band 40 to the ground line. Then, when the second antenna 42 is not transmitting, the line is made non-conductive (open). The open / close operation of the second open / close switch 2612 is performed based on the second control signal SEL2 input through the second input terminal 104.

  This limits the input of the V2X signal and the LTE Band 40 signal to the amplifier 50, so that a mixed signal of the frequency difference between the V2 X signal and the LTE second harmonic of the Band 40 does not occur. The generation of distortion when amplifying the GNSS signal in the amplifier 50 can be more effectively prevented as compared with the example of the input limiting circuit 160.

  In the present embodiment, an example in which the on / off switches 161, 2611, and 2612 are provided in the input limiting circuits 160 and 260 has been described. However, in the case of an application in which the configuration is simpler, these can be omitted. That is, one end of the BPF 162, the first BPF 2621, and the second BPF 2622 may be branch-connected between the third antenna 43 and the amplifier 50, and a ground line may be connected to the other end.

  FIG. 5 is a diagram showing the relationship between the noise figure of the amplifier 50 and the use frequency in the case where the switch 161 is not provided and in the input limiting circuit 160. When the open / close switch 161 is not provided, the BPF 162 is always connected to the third antenna 43 and the amplifier 50. As shown in FIG. 5, by providing the input limiting circuit 160, an effect is obtained in which the noise figure at frequencies of 1200 MHz or later approaches 1; such an effect is obtained by opening and closing when using the BPF 161, 2621, 2622. It does not largely depend on the presence or absence of the switch 161. However, if the on-off switch 161 is provided, the noise figure is surely lowered.

  Also, in the input limiting circuit 160, the BPF 162 is designed to resonate at the Band 40 of LTE and its impedance is minimized, but the BPF 162 is designed to resonate at the frequency of V2X and its impedance is minimized. It may be designed to resonate at both the Band 40 of LTE and the frequency of V2X and to minimize its impedance. Further, in the input limiting circuit 160, the open / close switch 161 conducts the branch connection line in a period during which both the first antenna 41 and the second antenna 42 are transmitting signals, respectively. It may be a period during which at least one of the antenna 41 and the second antenna 42 is transmitting a signal.

Second Embodiment
Next, a second embodiment of the present invention will be described. The antenna device of the second embodiment differs from that of the first embodiment in the configuration of the input limiting circuit. The configurations of the case portion and the antenna portion of the antenna device shown in FIGS. 1 and 2 are the same as those of the first embodiment, and therefore, the same reference numerals are given and duplicate explanations are omitted.

  FIG. 6 is a block diagram of an input limiting circuit provided in the antenna device of the second embodiment, and a block circuit diagram is shown. The input limiting circuit 360 is configured of a band elimination filter (BEF) 362 interposed between the third antenna 43 and the amplifier 50. The BEF 362 is, for example, a parallel resonant circuit in which a coil and a capacitor are connected in parallel, and is designed to resonate at, for example, Band 40 of LTE (2300 MHz to 2400 MHz) to maximize impedance.

When the signal of the Band 40 of LTE is transmitted from the second antenna 42, the input limiting circuit 360 blocks the signal in the direction of the amplifier 50 by the BEF 362. Therefore, since the input of the signal to the amplifier 50 is limited, even if the V2X 5850 MHz signal transmitted from the first antenna 41 flows into the amplifier 50, the second harmonic of the Band 40 of LTE is generated. Since it does not, the mixed signal of the above-mentioned difference frequency is not generated, either. Therefore, as in the first embodiment, the influence of the GNSS signal on the amplification system can be mitigated.
The BEF 362 may be designed to resonate at 5850 MHz of V2X, or may be designed to resonate at both 5850 MHz of V2 X and Band 40 of LTE.

Third Embodiment
Next, a third embodiment of the present invention will be described. The antenna device of the third embodiment differs from that of the first embodiment in the configuration of the input limiting circuit. The configurations of the case portion and the antenna portion of the antenna device shown in FIGS. 1 and 2 are the same as those of the first embodiment, and therefore, the same reference numerals are given and duplicate explanations are omitted.

  FIG. 7 is a block diagram of an input limiting circuit provided in the antenna device of the third embodiment, and a block circuit diagram is shown. The input limiting circuit 460 is a switch (path that selectively switches between a first path P1 in which the BEF 462 is interposed between the third antenna 43 and the amplifier 50 and a second path P2 in which the BEF 462 is bypassed. A switching circuit) 461 is included. The changeover switch 461 selects the first path P1 when both of the first antenna 41 and the second antenna 42 are transmitting, and otherwise selects the second path P2.

  The BEF 462 is, for example, a parallel resonant circuit in which a coil and a capacitor are connected in parallel, and is designed to resonate at an LTE Band 40 (2300 MHz to 2400 MHz) to maximize impedance.

  In the input control circuit 460 configured in this manner, the input to the amplifier 50 of the signal transmitted from the second antenna 42 is limited when both the first antenna 41 and the second antenna 42 are transmitting. Therefore, since the second harmonic of LTE Band 40 does not occur in amplifier 50, the influence of the GNSS signal on the amplification system can be mitigated.

FIG. 8 shows the noise figure and the operating frequency of the amplifier 50 in the case where the input limiting circuit 460 having the changeover switch 461 is provided and in the case where the input limiting circuit 360 having no changeover switch is provided as in the second embodiment. It is a figure which shows a relation. The former is not affected by the BEF 462 because the second path P2 is selected when the V2X signal and the LTE Band 40 signal are not transmitted, but the latter is for the transmission of the V2X signal and the LTE Band 40 signal. Regardless of the presence or absence, it will be affected by the BEF 362 being inserted.
As shown in FIG. 8, when the input limiting circuit 460 with the changeover switch 461 is provided, it is understood that the noise figure after the frequency around 1200 MHz is significantly improved as compared with the input limiting circuit 360 without the changeover switch.

  Furthermore, in the input limiting circuit 460, the BEF 462 is designed to resonate at the Band 40 of LTE to maximize the impedance, but the BEF 462 is designed to resonate at the frequency of V2X to maximize the impedance. It may be designed so that the impedance is maximized by resonating at both of the LTE Band 40 and V2X frequencies.

  Further, in the input limiting circuit 460, the switch 461 selects the first path P1 when both of the first antenna 41 and the second antenna 42 are transmitting, and otherwise selects the second path P2. However, when at least one of the first antenna 41 and the second antenna 42 is transmitting, the first path P1 may be selected, and when not, the second path P2 may be selected.

Fourth Embodiment
Next, a fourth embodiment of the present invention will be described. The antenna device of the fourth embodiment differs from the first embodiment in the configuration of the input limiting circuit. The configurations of the case portion and the antenna portion of the antenna device shown in FIGS. 1 and 2 are the same as those of the first embodiment, and therefore, the same reference numerals are given and duplicate explanations are omitted.

  FIG. 9 is a block diagram of an input limiting circuit provided in the antenna device of the fourth embodiment, and a block circuit diagram is shown. The input limiting circuit 560 connects a switching switch (path switching circuit) 561 for switching between the first path P1 in which the BEF 562 is inserted and the second path P2 in which the BEF 562 is bypassed to the feeding portion of the third antenna 43. And be configured. The changeover switch 561 is controlled by a control signal SEL input from the receiving device on the vehicle side through the input terminal 102. BEF 562 is a filter with the same electrical constant as BEF 462 of the third embodiment. The changeover switch 561 selects the first path P1 when both of the first antenna 41 and the second antenna 42 are transmitting, and otherwise selects the second path P2. Therefore, the same effect as that of the third embodiment can be obtained.

  Further, the fourth embodiment can suppress the decrease in the received power of the third antenna 43 in the path from the third antenna 43 to the amplifier 50 as compared with the third embodiment. This is considered to be because the third antenna 43 is not branched to the first path P1 when the second path P2 is selected.

Fifth Embodiment
Next, a fifth embodiment of the present invention will be described. The antenna device of the fifth embodiment differs from the fourth embodiment in the configuration of the input limiting circuit. The configurations of the case portion and the antenna portion of the antenna device are the same as in the first to fourth embodiments, and therefore, the same reference numerals are given and redundant description will be omitted.

  FIG. 10 is a block diagram of an input limiting circuit provided in the antenna device of the fifth embodiment, and a block circuit diagram is shown. The input limiting circuit 660 is a first changeover switch (a first path switching circuit for switching between a first path P1 in which the BEF 662 is interposed and a second path P2 in which the BEF 662 is bypassed. ) 661 and an input stage of the amplifier 50 is connected with a second changeover switch (second path switching circuit) 663 for switching between the first path P1 and the second path P2. The first changeover switch 661 is controlled by a control signal SEL1 input from the receiver on the vehicle side through the input terminal 102. The second changeover switch 663 is controlled by a control signal SEL2 input from the receiving device on the vehicle side through the input terminal 103. In addition, BEF662 is a filter of the same electrical constant as BEF462 of 3rd Embodiment.

  The first changeover switch 661 and the second changeover switch 663 select the first path P1 when both of the first antenna 41 and the second antenna 42 are transmitting, and otherwise select the second path P2 . Therefore, the same effect as that of the third embodiment can be obtained. In the fifth embodiment, since the BEF 662 is completely cut off when the second path P2 is selected, the third antenna in the path from the third antenna 43 to the amplifier 50 is compared with the fourth embodiment. There is an effect that the reduction of the reception power of 43 can be further suppressed.

  In the first to fifth embodiments, the first antenna 41 transmits a signal of V2X, the second antenna 42 transmits a signal of Band 40 of LTE, and the third antenna 43 transmits L1 band and L2 of GNSS. Although the example in the case of receiving the signal of a zone was explained, the frequency band of each antenna 41, 42, 43 is an illustration, and is not limited to the contents of the description. There are various frequency bands in V2X and LTE, and the frequency bands passed by BPF 162, 1st BPF 2621, and 2nd BPF 2622, or the frequency bands restricted in BEF 362, 462, 562, 662 depending on the frequency band used. Appropriate changes can be made.

The third frequency band is not limited to the L1 band and L2 band of GNSS, and may be a frequency band of SXM (2320 MHz to 2345 MHz). This is because the difference between V2X (5850 MHz to 5925 MHz) and the second harmonic of Band 4 (1710 MHz to 1755 MHz) of LTE overlaps with SXM (2320 MHz to 2345 MHz).
The present invention is also applicable to an antenna apparatus in which an antenna or the like for satellite digital audio radio service (SDARS) is gathered in one case unit, not limited to GNSS communication and SXM communication. .

  The embodiment of the present invention is as described above, but one of the features in each of the above-described embodiments is an amplifier 50 which should originally amplify only the signal of the third frequency band received by the third antenna 43. However, if it is possible to amplify also the signal of the third frequency band generated by the mixing of the signal of the first frequency band and the harmonics of the second frequency band, the signal of the first frequency band and the signal of the second frequency band Inputs to at least one of the amplifiers 50 are limited by the input limiting circuits 160, 260, 360, 460, 560, 660, whereby the first frequency band signal and the second harmonic generated from the second frequency band are mixed. A configuration that can suppress the generation of signals in three frequency bands and that can exhibit the same function and effect is within the scope of the disclosure of the present invention.

  Further, the input limiting circuits 160 and 260 in the first embodiment are branch-connected between the third antenna 43 and the amplifier 50, and a signal of at least one of the first frequency band or the second frequency band is a ground line Function including the BPFs 162, 2621, and 2622 which lead to the operation of the third embodiment 43 without providing a physical shield member or the like around the third antenna 43 etc. Can be played.

  Further, the input limiting circuit 260 is branch-connected between the third antenna 43 and the amplifier 50, and guides the signal of the first frequency band to the ground line and the signal of the second frequency band to the ground line. Since the 2BPF 2622 is configured, the input to the amplifier 50 of signals of two frequency bands can be limited. Therefore, since the input to both amplifiers 50 of the signal of the first frequency band transmitted from the first antenna 41 and the signal of the second frequency band transmitted from the second antenna 42 can be limited, the amplification system of the third frequency band can be used. The impact can be eliminated more strongly.

  Further, the input limiting circuits 160 and 260 according to the first embodiment further include open / close switches (line opening and closing circuits) 161, 2611 and 2612 for turning on and off the branched lines. The line is made conductive only while both the antenna 41 and the second antenna 42 are transmitting signals, and the input limiting circuit 260 is only transmitted while at least one of the first antenna 41 and the second antenna 42 is transmitting signals. Can be implemented to strictly limit the unnecessary input to the amplifier 50, and the noise figure of the amplifier 50 can be further reduced and improved (FIG. 5).

  Further, the input limiting circuit 360 according to the second embodiment passes signals in at least one of the first frequency band and the second frequency band, which are interposed between the third antenna 43 and the amplifier 50. Since it is comprised only by BEF362 which restricts, the antenna device of simpler composition can be realized.

  Further, the input limiting circuits 460, 560, 660 in the third to fifth embodiments are configured such that at least one of the frequencies of the signals in the first frequency band and the second frequency band is provided between the third antenna 43 and the amplifier 50. Switches 461, 561, 661, 663 for switching between the first path P1 in which the BEFs 462, 562, 662 are interposed, and the second path P2 in which the BEFs 462, 562, 662 are bypassed. Since the first path P1 is selected only while both the first antenna 41 and the second antenna 42 transmit signals, the amplification system of the third frequency band affected by the harmonics is included. Can be more efficiently mitigated (Figure 8).

The antenna apparatus provided by the present invention is different from a first antenna transmitting a signal of a first frequency band, a second antenna transmitting a signal of a second frequency band, and the first frequency band and the second frequency band. It is possible to amplify a mixed signal generated by mixing the signal of the first frequency band and the signal of the second frequency band in addition to the third antenna receiving the signal of the third frequency band and the signal received by the third antenna And an input limiting circuit for limiting the input of at least one of the signal of the first frequency band and the signal of the second frequency band to the amplifier.
The input limiting circuit is, for example, a band pass filter which is branched and connected between the third antenna and the amplifier and guides a signal of at least one of the first frequency band or the second frequency band to a ground line. And a line open / close circuit for making the branch-connected line conductive or non-conductive, wherein the line open / close circuit transmits the signal while at least one of the first antenna and the second antenna transmits a signal. Conduct the line.
Alternatively, the input limiting circuit is branched and connected between the third antenna and the amplifier, and guides the signal of the first frequency band to a ground line, and the signal of the second frequency band. A second band pass filter leading to a ground line, and a line switching circuit for making the branched line conductive or nonconductive, the line switching circuit comprising at least one of the first antenna and the second antenna The line is made conductive while transmitting a signal.
Alternatively, band elimination that restricts the passage of signals in at least one of the first frequency band and the second frequency band between the other third antenna and the amplifier. And a path switching circuit that selectively switches between a first path in which a filter is inserted and a second path in which the band elimination filter is bypassed. The first path is selected while at least one of the antenna and the second antenna is transmitting a signal.

Claims (9)

A first antenna transmitting a signal in a first frequency band;
A second antenna transmitting a signal in a second frequency band;
A third antenna for receiving a signal of a third frequency band different from the first frequency band and the second frequency band;
An amplifier capable of amplifying a mixed signal generated by mixing the signal of the first frequency band and the signal of the second frequency band in addition to the signal received by the third antenna;
An input limiter circuit for limiting the input of at least one of the first frequency band signal and the second frequency band signal to the amplifier;
An antenna device comprising the The input limiting circuit includes a band pass filter which is branched between the third antenna and the amplifier and guides a signal of at least one of the first frequency band or the second frequency band to a ground line. Composed of
The antenna device according to claim 1. The input limiting circuit is branch-connected between the third antenna and the amplifier, and guides the signal of the first frequency band to the ground line, and the ground line of the signal of the second frequency band. Comprising a second band pass filter leading to
The antenna device according to claim 1. The input limiting circuit further includes a line open / close circuit for making the branch connected line conductive or nonconductive.
The line opening / closing circuit conducts the line while at least one of the first antenna and the second antenna is transmitting a signal.
The antenna device according to claim 2 or 3. The input limiter circuit is a band-elim for limiting the passage of signals of at least one of the first frequency band and the second frequency band, which is interposed between the third antenna and the amplifier. Is a nation filter,
The antenna device according to claim 1. The input limiting circuit includes a band elimination filter between the third antenna and the amplifier for limiting passage of signals in at least one of the first frequency band and the second frequency band. And a path switching circuit that selectively switches between the inserted first path and the second path through which the band elimination filter is bypassed,
The path switching circuit selects the first path while at least one of the first antenna and the second antenna is transmitting a signal.
The antenna device according to claim 1. The first frequency band is a V2X frequency band,
The second frequency band is any frequency band of LTE,
The third antenna is a satellite communication reception antenna,
The amplifier is a semiconductor circuit for amplifying a satellite communication signal received by the third antenna,
A mixed signal of the difference between the first frequency band and the second harmonic or the third harmonic of the second frequency band is generated in the third frequency band,
The antenna device according to any one of claims 1 to 6. Radio wave transparent antenna case,
And an antenna base on which the antenna case is fitted.
The first antenna, the second antenna, the third antenna, the amplifier, and the input limiting circuit are mounted in a storage space formed between the inside of the antenna case and the upper portion of the antenna base.
The antenna device according to any one of claims 1 to 7. The first antenna and the second antenna are planar antennas erected on the antenna base,
The third antenna is a patch antenna disposed at a position lower than upper edges of the first antenna and the second antenna.
The antenna device according to claim 8.

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