JP2012029274A - Interference control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an interference control device capable of suppressing interference due to a sneak-path wave in both directions by attaining a simple configuration while minimizing deterioration of communication quality.SOLUTION: An interference control device includes coupling means for extracting a part of transmission signals transmitted from an antenna of a first radio communication equipment from a power feed line of the first radio communication equipment and conveying the transmission signals to a power feed line of a second radio communication equipment and extracting a part of transmission signals transmitted from an antenna of the second communication equipment from the power feed line of the second radio communication equipment and conveying the transmission signals to the power feed line of the first radio communication equipment, and adjustment means, which is installed between the antenna connected to the power feed line and the coupling means in at least one of the power feed lines of the first radio communication equipment and the second radio communication equipment, for adjusting at least a phase out of the phase and power level of the signals conveyed on the power feed line according to a transmission timing of the first radio communication equipment and the second communication equipment.

Description

  The present invention relates to an interference suppression apparatus that suppresses interference caused by a sneak wave from an antenna of one wireless communication device to an antenna of the other wireless communication device in two wireless communication devices for transmission and reception having different use frequencies. .

  Conventionally, as described in Patent Documents 1 and 2, for example, interference caused by a sneak wave that propagates through the space from the transmission antenna of the first wireless communication device to the reception antenna of the second wireless communication device is suppressed, that is, in the received signal. There is known an interference suppression apparatus for reducing a mixed sneak wave component.

  This interference suppression device (interference wave removing device, interference noise removing device) includes means for extracting a part of a transmission signal transmitted from a transmission antenna, means for adjusting at least the phase of the extracted signal, and an adjusted signal. Is coupled to the received signal of the receiving antenna, and the sneak wave component included in the received signal is canceled by the adjusted signal.

Japanese Patent Laid-Open No. 7-30459 JP 2008-259195 A

  In the conventional interference suppression devices disclosed in Patent Literatures 1 and 2, one of the two wireless communication devices is dedicated to reception, and suppresses interference due to a sneak wave from the transmission antenna (or transmission / reception antenna) to the reception antenna. Can do. However, in the two wireless communication devices for transmission and reception, interference due to a sneak wave from the antenna of the first wireless communication device to the antenna of the second wireless communication device and the antenna of the first wireless communication device from the antenna of the second wireless communication device. Both interferences due to sneak waves cannot be suppressed.

  For example, by providing another set of interference suppression devices disclosed in Patent Documents 1 and 2, interference caused by a sneak wave from the antenna of the first wireless communication device to the antenna of the second wireless communication device and the antenna of the second wireless communication device It is also conceivable to suppress both interference due to sneak waves from the antenna to the antenna of the first wireless communication device.

  In this case, since two means for extracting a part of the transmission signal and two means for coupling to the reception signal are required, the configuration is complicated, thereby increasing the cost.

  In view of the above problems, an object of the present invention is to provide an interference suppression apparatus capable of suppressing interference caused by a sneak wave in both directions with a simple configuration while suppressing deterioration in communication quality.

  In order to achieve the above object, an interference suppression apparatus according to claim 1 includes a coupling means. When the first wireless communication device transmits and the second wireless communication device receives, the coupling means extracts a part of the transmission signal that propagates through the power supply line of the first wireless communication device, and supplies power to the second wireless communication device. Tell (distribute) to the line. For this reason, a transmission signal that is not transmitted to the power supply line of the second wireless communication device but remains in the power supply line of the first wireless communication device is transmitted to the outside from the antenna of the first wireless communication device.

  On the other hand, when the second wireless communication apparatus transmits and the first wireless communication apparatus receives, the coupling means extracts a part of the transmission signal propagating through the power supply line of the second wireless communication apparatus, and the first wireless communication apparatus (Distribute) to the power supply line. For this reason, a transmission signal that is not transmitted to the power supply line of the first wireless communication device and remains in the power supply line of the second wireless communication device is transmitted to the outside from the antenna of the second wireless communication device.

  In addition, an adjustment unit that adjusts at least the phase of the phase and the power level is provided between the antenna and the coupling unit in at least one of the feeding lines of the first wireless communication device and the second wireless communication device. This adjusting means is a signal that propagates through a power supply line provided with the adjusting means according to the transmission timing of the first wireless communication device and the second wireless communication device (the transmission signal and the antenna before being transmitted from the antenna to the outside). At least one of the reception signals of the sneak wave received in step (b). The reception signal of the sneak wave transmitted from the antenna of the first radio communication apparatus and received by the antenna of the second radio communication apparatus is canceled by the signal distributed by the coupling means from the first radio communication apparatus to the second radio communication apparatus. As described above, at least the phase is adjusted by the adjusting means. Further, the reception signal of the sneak wave transmitted from the antenna of the second wireless communication device and received by the antenna of the first wireless communication device is a signal distributed by the coupling means from the second wireless communication device to the first wireless communication device. At least the phase is adjusted by the adjusting means so as to be canceled by.

  As described above, according to the present invention, interference due to a sneak wave can be bi-directionally suppressed in two wireless communication apparatuses having different operating frequencies by one coupling means and adjusting means. Therefore, it is possible to provide an interference suppression device capable of suppressing interference caused by sneak waves in both directions with a simple configuration while suppressing deterioration in communication quality.

  The adjusting means is set in advance based on the arrangement of the antennas and the feed lines that constitute both wireless communication devices so as to cancel out the sneak wave. Further, cancellation means reducing a sneak wave component in the received signal.

  Of the first wireless communication device and the second wireless communication device, as described in claim 2, when the adjustment means is provided only in the power supply line of the first wireless communication device, the adjustment means is provided in each of the power supply lines of the two wireless communication devices. Compared to the configuration in which the apparatus is provided, the apparatus configuration can be simplified.

  At this time, as described in claim 3, when the first wireless communication device transmits and the second wireless communication device receives, the first adjustment for adjusting the transmission signal transmitted from the antenna of the first wireless communication device The second adjustment means for adjusting the received signal received by the antenna of the first wireless communication device is selected when the means is selected, transmitted by the second wireless communication device and received by the first wireless communication device. good.

  On the other hand, as described in claim 4, when the adjusting means has a variable phase shifter, and the first wireless communication device transmits and the second wireless communication device receives, the variable phase shifter transmits the first wireless communication. When the phase of the transmission signal transmitted from the antenna of the communication device is adjusted, the second wireless communication device transmits, and the first wireless communication device receives, the variable phase shifter receives at the antenna of the first wireless communication device. A configuration in which the phase of the signal is adjusted may be employed.

  As described in claim 5, a 4-port directional coupler can be adopted as the coupling means. Furthermore, as described in claim 6, it is possible to adopt a configuration in which the output direction of the signal extracted by the coupling means (directional coupler) is the feeding point side in any feeding line.

  In addition, as described in claim 7, when a 6-port directional coupler is employed as the coupling means, the second wireless communication apparatus is a diversity system having two sets of an antenna and a feed line connected to the antenna. In the wireless communication device, interference due to a sneak wave can be suppressed in both directions by one coupling means and adjusting means. Therefore, it is possible to provide an interference suppression device capable of suppressing interference caused by sneak waves in both directions with a simple configuration while suppressing deterioration in communication quality. Furthermore, as described in claim 8, it is possible to adopt a configuration in which the output direction of the signal extracted by the coupling means (directional coupler) is the feeding point side in any feeding line.

  As described in claim 9, the power supply line of the first wireless communication device and the power supply line of the second wireless communication device are configured as microstrip lines with respect to the same dielectric substrate, and a part of both power supply lines If the microstrip line type directional coupler is used as the coupling means, the configuration of the interference suppression device can be further simplified.

It is a figure which shows schematic structure of the radio | wireless communication apparatus to which the interference suppression apparatus which concerns on 1st Embodiment of this invention was applied. It is a perspective view which shows schematic structure of the interference suppression apparatus shown in FIG. It is a figure which shows the interference suppression by a sneak wave when a 1st radio | wireless communication apparatus transmits and a 2nd radio | wireless communication apparatus receives. It is a figure which shows the interference suppression by a sneak wave when a 2nd wireless communication apparatus transmits and a 1st wireless communication apparatus receives. It is a figure which shows the measurement result of a passage loss. It is a block diagram which shows the modification of the radio | wireless communication apparatus to which the interference suppression apparatus was applied. It is a perspective view which shows schematic structure of the interference suppression apparatus shown in FIG. It is a figure which shows schematic structure of the radio | wireless communication apparatus with which the interference suppression apparatus which concerns on 2nd Embodiment was applied. It is a figure which shows schematic structure of a variable phase shifter. It is a perspective view which shows schematic structure of the interference suppression apparatus shown in FIG. It is a figure which shows the measurement result of a passage loss. It is a figure which shows the other modification of the radio | wireless communication apparatus to which the interference suppression apparatus was applied. It is a figure which shows the other modification of the radio | wireless communication apparatus to which the interference suppression apparatus was applied. It is a figure which shows the other modification of the radio | wireless communication apparatus to which the interference suppression apparatus was applied.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, the same code | symbol shall be provided to a common thru | or related element.

(First embodiment)
In FIG. 1, not only the interference suppression device 30 according to the present embodiment but also a wireless communication device to which the interference suppression device 30 is applied is shown.

  As shown in FIG. 1, the wireless communication apparatus includes a first transceiver 10 (also referred to as a wireless circuit or a power feeding circuit) having a transmission unit, a reception unit, and a switching unit (for example, a diplexer) that switches between transmission and reception, which are not illustrated. A second transceiver 20 (wireless) having a first wireless communication device S1 that is connected to the antenna 11 via a first feed line 12, a transmission unit, a reception unit, and a switching unit (for example, a diplexer) that switches between transmission and reception (not shown). A second wireless communication device S <b> 2 in which the second antenna 21 is connected by a second power supply line 22. In addition, the first wireless communication device S1 can also be referred to as a first wireless communication system, and the second wireless communication device S2 can also be referred to as a second wireless communication system.

  Thus, the two wireless communication devices S1 and S2 are transmission / reception wireless communication devices. Moreover, the 1st antenna 11 and the 2nd antenna 21 are arrange | positioned closely so that a sneak wave may mix.

  In the present embodiment, the first wireless communication device S1 is a vehicle-to-vehicle wireless communication device that uses the 720 MHz band as a use frequency and performs data communication between the host vehicle and another vehicle. The second wireless communication device S2 is a wireless communication device for DCM (Data Communication Module) that uses the 850 MHz band as a use frequency and performs data communication between the vehicle and the center. That is, the first radio communication device S1 and the second radio communication device S2 use different frequencies and are close to each other.

  In the first wireless communication device S1 and the second wireless communication device S2, the interference suppression device 30 causes the transmission wave of the first wireless communication device S1 (first antenna 11) to be transmitted to the second wireless communication device by coupling between the antennas 11 and 21. For suppressing interference given to the device S2 (second antenna 21) and interference given by the transmission wave of the second wireless communication device S2 (second antenna 21) to the first wireless communication device S1 (first antenna 11) Device. In other words, this is a device for suppressing a decrease in the S / N ratio (signal-to-noise ratio) due to the sneak wave mixed into the received signals at the antennas 11 and 21.

  The interference suppression device 30 extracts a part of the first transmission signal transmitted from the first antenna 11 from the first power supply line 12 and transmits (distributes) it to the second power supply line 22, and at the same time the second antenna 21. A four-port directional coupler 31 is provided as a coupling means for extracting (transmitting) a part of the second transmission signal transmitted from the second feeder line 22 from the second feeder line 22 and transmitting (distributing) it to the first feeder line 12. The directional coupler 31 is inserted in the power supply lines 12 and 22 of the wireless communication devices S1 and S2.

  In the present embodiment, among the four ports P1 to P4 of the directional coupler 31, a portion on the feeding point 13 side in the first feeding line 12 is connected to the first port P1, and the first feeding line is connected to the second port P2. 12 is connected to the first antenna 11 side. Further, a portion on the feeding point 23 side in the second feeding line 22 is connected to the third port P3, and a portion on the second antenna 21 side in the second feeding line 22 is connected to the fourth port P4. When the first wireless communication device S1 transmits, that is, when the first transmission signal is input from the first transceiver 10 to the first port P1 through the feeding point 13, the first transmission signal is connected to the second port P2. The data is output to the third port P3. When the second wireless communication device S2 transmits, that is, when the second transmission signal is input from the second transceiver 20 to the third port P3 via the feeding point 23, the second transmission signal is connected to the fourth port P4. It is output to the first port P1.

  In addition, the interference suppression device 30 serves as an adjustment unit provided between the first antenna 11 and the connection point of the directional coupler 31 in the first feed line 12, and includes at least one of the phase and the power level of the first transmission signal. A first adjustment unit 32 that adjusts the phase and a second adjustment unit 33 that adjusts at least the phase of the phase and power level of the received signal received by the first antenna 11 are provided. The first adjustment unit 32 corresponds to the first adjustment unit described in the claims, and the second adjustment unit 33 corresponds to the second adjustment unit.

  In the present embodiment, the first adjustment unit 32 includes a phase shifter 32a that adjusts the phase of the first transmission signal before being transmitted by the first antenna 11, and an attenuator that adjusts the power level of the first transmission signal. 32b. The phase shifter 32a and the attenuator 32b are provided on the transmission side selection path 12b (see FIG. 2), which will be described later, of the first feed line 12. The second adjustment unit 33 includes a phase shifter 33a that adjusts the phase of the reception signal received by the first antenna 11, and an attenuator 33b that adjusts the power level of the reception signal. The phase shifter 33a and the attenuator 33b are provided in the selection path 12c (see FIG. 2) on the receiving side, which will be described later, of the first feed line 12.

  The phase shifter 32a and the attenuator 32b transmit a signal based on a sneak wave transmitted from the first antenna 11 and received by the second antenna 21 from the first port P1 to the third port P3 in the directional coupler 31. In order to adjust the phase and power level of the first transmission signal transmitted from the first antenna 11 so as to be offset by a part of the first transmission signal (hereinafter referred to as a first distribution signal) output to It is set in advance. Specifically, the phase of the signal based on the sneak wave received by the second antenna 21 at the portion where it is combined with the first distribution signal is opposite to the phase of the first distribution signal (180 ° deviation). It is set to become. In addition, the power level of the signal based on the sneak wave received by the second antenna 21 at the portion where it is combined with the first distribution signal is set to be approximately the same as the power level of the first distribution signal. Yes.

  On the other hand, the phase shifter 33a and the attenuator 33b receive a signal based on a sneak wave transmitted from the second antenna 21 and received by the first antenna 11 from the third port P3 in the first direction. In order to adjust the phase and power level of the reception signal received by the first antenna 11 so as to be offset by a part of the second transmission signal output to the port P1 (hereinafter referred to as a second distribution signal), Is set. Specifically, the phase of the signal based on the sneak wave received by the first antenna 11 at the portion where it is combined with the second distribution signal is opposite to the phase of the second distribution signal (180 ° deviation). It is set to become. In addition, the power level of the signal based on the sneak wave received by the first antenna 11 at the portion where it is combined with the second distribution signal is set to be approximately the same as the power level of the second distribution signal. Yes.

  The interference suppression apparatus 30 selects the first adjustment unit 32 when the first wireless communication device S1 transmits through the first antenna 11 and the second wireless communication device S2 receives through the second antenna 21, and the second adjustment device 32 selects the second adjustment unit 32. As a selection means for selecting the second adjustment unit 33 when the wireless communication device S2 transmits through the second antenna 21 and the first wireless communication device S1 receives through the first antenna 11, a pair of switches 34 and 35, and these And a selection signal generation unit 36 that generates a signal for switching the switches 34 and 35.

  The switches 34 and 35 are provided between the connection points of the first antenna 11 and the directional coupler 31 in the first feed line 12 so as to sandwich the first adjustment unit 32 and the second adjustment unit 33. A switch 34 is provided on the directional coupler 31 side, and a switch 35 is provided on the first antenna 11 side.

  In the selection signal generation unit 36, when the first antenna 11 transmits and the second antenna 21 receives, the switches 34 and 35 select the first adjustment unit 32, the second antenna 21 transmits, and the first antenna 11 Is generated so that the switches 34 and 35 select the second adjustment unit 33 when the signal is received, according to the transmission / reception states of the first wireless communication device S1 and the second wireless communication device S2.

  In the present embodiment, as shown in FIG. The control unit 37 controls the transmission / reception mode (transmission / reception timing) of the first transceiver 10 of the first wireless communication device S1 and the second transceiver 20 of the second wireless communication device S2. The selection signal generation unit 36 acquires a mode signal for setting a transmission state from the control unit 37, and generates a selection signal based on the mode signal. When the first wireless communication device S1 is in the transmission mode and the second wireless communication device S2 is in the reception mode, a signal for selecting the first adjustment unit 32 is generated, and the second wireless communication device S2 is in the transmission mode and the first wireless communication device. When the communication device S1 is in the reception mode, a signal for selecting the second adjustment unit 33 is generated. When both wireless communication devices S1 and S2 are in the transmission mode, a signal for selecting either one of the predetermined communication devices (for example, the first adjustment unit 32) is generated, and both wireless communication devices S1 and S2 are in the reception mode. In this case, a signal for selecting one of the predetermined ones (for example, the second adjustment unit 33) is generated.

  Next, a specific configuration example of the above-described interference suppression device 30 will be described.

  Reference numeral 40 shown in FIG. 2 is a dielectric substrate made of resin or ceramic, and a ground plane 41 (in other words, a reflection plate) is provided on one surface of the planar rectangular dielectric substrate 40. A microstrip line 42 formed by patterning a conductive foil such as copper is disposed on the surface of the dielectric substrate 40 opposite to the ground plane installation surface. The ground plane 41 and the microstrip line 42 arranged in parallel via the dielectric substrate 40 constitute a microstrip line.

  Two microstrip lines 42 are arranged on the dielectric substrate 40, one of which forms the first power supply line 12 and the other of which forms the second power supply line 22. The second power supply line 22 has a planar crank shape, and one end of the crank-shaped second power supply line 22 is located at the end of the long side of the planar rectangular dielectric substrate 40 and serves as a power supply point 23. A second antenna 21 having a monopole structure is mounted on the other end of the crank-shaped second feeding line 22.

  On the other hand, the first power supply line 12 has a planar crank shape from the power supply point 13 to the switch 34, and one end forming the power supply point 13 is at the end of the long side of the dielectric substrate 40 that is the same as the power supply point 23. positioned. The portion of the crank-shaped first power supply line 12 and the crank-shaped second power supply line 22 have parallel portions 12a and 22a arranged in parallel at a predetermined interval, and these parallel portions 12a. , 22a constitutes a microstrip line type directional coupler 31. Note that the length of the parallel portions 12a and 22a (the length in the direction orthogonal to the interval direction) is about λ / 4 with respect to either wavelength λ of the two wireless communication devices S1 and S2. Is set to the length of

  In addition, in a portion between the portions where the switches 34 and 35 are inserted in the first power supply line 12, a selection path 12b on the transmission side and a selection path 12c on the reception side are arranged in parallel. One of the selection paths 12b and 12c arranged in parallel with the microstrip line 42 is used as the first feed line 12 by the switches 34 and 35 so as to electrically connect the first antenna 11 and the feed point 13. It is provided to be selected. The transmission side selection path 12b is provided with a phase shifter 32a and an attenuator 32b, and the phase shifter 32a is configured by a microstrip line 42 having a predetermined length. The selection path 12c on the receiving side is provided with a phase shifter 33a and an attenuator 33b, and the phase shifter 33a is also composed of a microstrip line 42 having a predetermined length.

  The first antenna 11 having a monopole structure is mounted on the end of the first power feed line 12 opposite to the feed point 13.

  In the example shown in FIG. 2, the selection signal generation unit 36 that serves as a selection unit together with the switches 34 and 35 is provided separately from the dielectric substrate 40, and the switches 34 and 35 and the selection signal generation unit 36 are electrically connected. Illustration of wiring (for example, the microstrip line 42) connected to is omitted. However, a configuration in which the selection signal generation unit 36 is mounted on the dielectric substrate 40 can be employed.

  Next, the interference suppression effect by the above-described interference suppression device 30 will be described.

  First, the case where the second antenna 21 of the second radio communication device S2 receives the signal transmitted from the first antenna 11 of the first radio communication device S1 by inter-antenna coupling will be described with reference to FIG. Based on the instruction signal from the control unit 37, the transmission unit of the first transceiver 10 generates a first transmission signal. The first transmission signal propagates through the first feed line 12 via the feed point 13 and is input to the first port P1 of the directional coupler 31. And it outputs from the 2nd port P2 connected to the 1st electric power feeding line 12, and the 3rd port P3 connected to the part by the side of the electric power feeding point 23 of the 2nd electric power feeding line 22. FIG. Thus, a part of the first transmission signal is distributed from the first power supply line 12 to the second power supply line 22. Hereinafter, a signal distributed to the second power supply line 22 is referred to as a first distribution signal.

  The first transmission signal output from the second port P2 of the directional coupler 31 passes through the selection path 12b selected by the switches 34 and 35 as the selection means and the selection signal generation unit 36, and enters the selection path 12b. The phase and power level are adjusted by the provided first adjustment unit 32. Then, it is transmitted from the first antenna 11.

  Of the first transmission signal transmitted from the first antenna 11 to the outside, a sneak wave that propagates in space and is received by the second antenna 21 passes through the second feed line 22 and passes through the fourth directional coupler 31. The signal is input to the port P4 and output from the third port P3. Then, the second distribution line 22 is coupled and offset with the first distribution signal at a portion closer to the feeding point 23 than the directional coupler 31. Thus, at the timing when the first antenna 11 of the first wireless communication device S1 transmits, a signal based on the sneak wave of the first transmission signal transmitted from the first antenna 11 interferes with the reception signal of the second antenna 21. Can be suppressed.

  Next, the case where the first antenna 11 of the first radio communication device S1 receives the signal transmitted by the second antenna 21 of the second radio communication device S2 by inter-antenna coupling will be described with reference to FIG. Based on the instruction signal from the control unit 37, the transmission unit of the second transceiver 20 generates a second transmission signal. The second transmission signal propagates through the second feed line 22 via the feed point 23 and is input to the third port P3 of the directional coupler 31. And it outputs from the 4th port P4 connected to the 2nd electric power feeding line 22, and the 1st port P1 connected to the part by the side of the electric power feeding point 13 of the 1st electric power feeding line 12. FIG. Thus, a part of the second transmission signal is distributed from the second power supply line 22 to the first power supply line 12. Hereinafter, a signal distributed to the first power supply line 12 is referred to as a second distribution signal.

  The second transmission signal output from the fourth port P4 of the directional coupler 31 propagates through the second feed line 22 and is transmitted from the second antenna 21 to the outside. Of the second transmission signal transmitted from the second antenna 21, the sneak wave propagated through the space and received by the first antenna 11 is input to the first feed line 12 and selected by the switches 34 and 35 as selection means. The phase and power level are adjusted by the second adjustment unit 33 provided on the selection path 12c through the selection path 12c selected by the signal generation unit 36.

  The adjusted reception signal is input to the second port P2 of the directional coupler 31 via the first power supply line 12, and is output from the first port P1. Then, the first distribution line 12 is coupled / cancelled with the second distribution signal at a portion closer to the feeding point 13 than the directional coupler 31. Thus, at the timing when the second antenna 21 of the second wireless communication device S2 transmits, a signal based on the sneak wave of the second transmission signal transmitted from the second antenna 21 interferes with the reception signal of the first antenna 11. Can be suppressed.

  As described above, according to the interference suppression device 30 according to the present embodiment, one directional coupler 31 (coupling unit), two adjustment units 32 and 33 (adjustment unit), switches 34 and 35, and a selection signal generation unit 36 are provided. By the (selection means), interference due to a sneak wave can be suppressed bidirectionally in the two wireless communication devices S1 and S2 having different operating frequencies. Therefore, it is possible to provide the interference suppression device 30 that can suppress interference caused by the sneak wave in both directions with a simple configuration while suppressing deterioration in communication quality.

  The inventor made a prototype of the interference suppression device 30 shown in FIG. 2 in which the antennas 11 and 21 are mounted on the dielectric substrate 40, and measured the passage loss. The result is shown by a solid line in FIG. A broken line shown in FIG. 5 indicates a passage loss without the interference suppression device 30. As shown in FIG. 5, by providing the interference suppression device 30, the passage loss is reduced in both the first wireless communication device S1 (720 MHz band) and the second wireless communication device S2 (850 MHz band). Also from this, it is clear that communication quality deterioration was suppressed by interference suppression.

  In the present embodiment, the first power supply line 12 and the second power supply line 22 are configured as a microstrip line 42 with respect to the same dielectric substrate 40, and one of the first power supply line 12 and the second power supply line 22 is configured. A microstrip line type directional coupler 31 is used. Therefore, the configuration of the interference suppression device 30 can be further simplified. In FIG. 2, the feed lines 12 and 22 are formed on the surface of the dielectric substrate 40 opposite to the ground plane 41, and the parallel portions 12 a and 22 a are arranged in parallel to the surface of the dielectric substrate 40. The example which makes the directional coupler 31 was shown. However, a directional coupler 31 in which the dielectric substrate 40 is a multilayer substrate and the parallel portions 12a and 22a are arranged in parallel in the thickness direction of the dielectric substrate 40 may be employed.

  Further, in the present embodiment, the first adjusting unit 32 and the second adjusting unit 33 include phase shifters 32a and 33a, respectively, and each phase shifter 32a and 33a is configured by a microstrip line 42 having a predetermined length. ing. Therefore, the configuration of the interference suppression device 30 can be further simplified.

(Modification)
In the present embodiment, the example in which the first adjustment unit 32 includes the phase shifter 32a and the attenuator 32b, and the second adjustment unit 33 includes the phase shifter 33a and the attenuator 33b is shown. However, the 1st adjustment part 32 and the 2nd adjustment part 33 should just have the phase shifters 32a and 33a at least. For example, by adjusting the degree of coupling of the directional coupler 31, the power level at the portion where the signal based on the sneak wave received by the second antenna 21 is combined with the first distribution signal is changed to the first distribution signal. The power level at the portion where the signal based on the sneak wave received by the first antenna 11 is combined with the second distribution signal is approximately the same as the power level of the second distribution signal. It can also be made.

  Moreover, although the phase shifters 32a and 33a have shown the example comprised by the microstrip line 42 which has predetermined length, the phase shifters 32a and 33a are not limited to the said example, Well-known thing Can be adopted. For example, phase shifters 32a and 33a composed of lumped constant elements may be employed.

  In this embodiment, when the directional coupler 31 of the four ports P1 to P4 inputs the first transmission signal to the first port P1, the directional coupler 31 outputs to the second port P2 and the third port P3, and outputs to the third port P3. An example of a configuration in which two transmission signals are input to the fourth port P4 and the first port P1 is shown. That is, an example of a right-handed coupler formed using a material (so-called right-handed material) having positive values of both dielectric constant and magnetic permeability is shown as the directional coupler 31. However, as shown in FIG. 6, when the first transmission signal is input to the first port P1, it is output to the second port P2 and the fourth port P4, and when the second transmission signal is input to the fourth port P4, the third transmission signal is output. A directional coupler 31 configured to output to the port P3 and the first port P1 may be employed. That is, as the directional coupler 31, a left-handed coupler formed using a material having a negative dielectric constant and permeability (so-called left-handed material) may be employed.

  When the directional coupler 31 having such a configuration is employed, the configuration of the interference suppression device 30 using the microstrip line 42 is as shown in FIG. In this configuration, the end of the first feeding line 12 on the feeding point 13 side is arranged on the end side of the second feeding line 22 on the second antenna 21 side. Therefore, in the configuration shown in FIG. A connection via 43 provided in the body substrate 40 is connected to a connector or a coaxial cable on the arrangement surface side of the ground plane 41 of the dielectric substrate 40. The ground plane 41 is formed so as to avoid the formation site of the connection via 43.

(Second Embodiment)
In this embodiment, one of the two wireless communication devices S1 and S2 is a diversity wireless communication device. In FIG. 8 shown as an example, the second wireless communication device S2 is a diversity wireless communication device.

  The second wireless communication device S2 connects one second transceiver 20 (also referred to as a wireless circuit or a power feeding circuit), two antennas 21 and 51, and each antenna 21 and 51 and the second transceiver 20 respectively. Two power supply lines 22 and 52 are provided. That is, two sets of antennas and feeds, that is, the second antenna 21 and the second feed line 22 connected to the second antenna 21, and the third antenna 51 and the third feed line 52 connected to the third antenna 51. Has a line.

  Of the antennas 21 and 51 of the second wireless communication device S2, the second antenna 21 is a transmission / reception antenna, and the third antenna 51 is a reception antenna. Further, the first antenna 11 and the second antenna 21, and the first antenna 11 and the third antenna 51 are arranged close to each other so that a sneak wave is mixed therein.

  In the present embodiment, the first wireless communication device S1 is a vehicle-to-vehicle wireless communication device that uses the 720 MHz band as a use frequency and performs data communication between the own vehicle and another vehicle, as in the first embodiment. Yes. The second wireless communication device S2 is a wireless communication device for telephones that uses the 900 MHz band as a use frequency. That is, the first radio communication device and the second radio communication device have different transmission / reception frequencies and are close to each other.

  The interference suppression device 30 extracts a part of the first transmission signal transmitted from the first antenna 11 of the first wireless communication device S1 from the first power supply line 12, and extracts both the power supply lines 22 of the second wireless communication device S2. , 52 and a part of the second transmission signal transmitted from the second antenna 21 of the second wireless communication device S2 is extracted from the second power supply line 22 and the first power supply line of the first wireless communication device S1 is extracted. As a coupling means for transmitting to 12, a 6-port directional coupler 31 is provided. The directional coupler 31 is inserted into the power supply lines 12, 22, and 52 of the wireless communication devices S1 and S2.

  In the present embodiment, of the six ports P1 to P6 of the directional coupler 31, a portion on the feeding point 13 side in the first feeding line 12 is connected to the first port P1, and the first feeding line is connected to the second port P2. 12 is connected to the first antenna 11 side. Further, a portion on the feeding point 23 side in the second feeding line 22 is connected to the third port P3, and a portion on the second antenna 21 side in the second feeding line 22 is connected to the fourth port P4. In addition, a portion on the feeding point 53 side in the third feeding line 52 is connected to the fifth port P5, and a portion on the third antenna 51 side in the third feeding line 52 is connected to the sixth port P6.

  When the first wireless communication device S1 transmits, that is, when the first transmission signal is input from the first transceiver 10 to the first port P1 via the feeding point 13, the first transmission signal is transmitted to the second port P2. Are output to the third port P3 and the fifth port P5. When the second wireless communication device S2 transmits, that is, when the second transmission signal is input from the second transceiver 20 to the third port P3 via the feeding point 23, the second transmission signal is connected to the fourth port P4. It is output to the first port P1.

  In the present embodiment, the power level of the signal based on the sneak wave received by the second antenna 21 and the third antenna 51 at the portion combined with the first distribution signal is the power level of the first distribution signal. So that the power level of the signal based on the sneak wave received by the first antenna 11 at the portion where it is combined with the second distribution signal is approximately the same as the power level of the second distribution signal. The degree of coupling of the directional coupler 31 is set. For this reason, it does not have an attenuator as the adjusting means described later.

  In addition, the interference suppression device 30 includes a variable phase shifter 38 as an adjustment unit provided between the first antenna 11 and the connection point of the directional coupler 31 in the first feed line 12. In this embodiment, as shown in FIG. 9, a so-called hybrid variable phase shifter using a coil and a capacitor is employed as the variable phase shifter 38. Specifically, coils 37a, 37b, 37d, 37e, 37i, 37l, 37m, 37q, capacitors 37c, 37f, 37g, 37k, 37n, 37o, 37s, variable capacitance diodes (varactors) 37h, 37p, Resistors 37j and 37r are provided. Then, the capacitance values of the variable capacitance diodes 37h and 37p change in accordance with a signal (voltage) from the capacitance adjustment unit 39 described later.

  In addition, the interference suppression device 30 changes the capacitance values of the variable capacitance diodes 37h and 37p in the variable phase shifter 38 according to the transmission / reception timings of the first wireless communication device S1 and the second wireless communication device S2. have. In the present embodiment, the capacity adjustment unit 39 controls the transmission / reception mode (transmission / reception timing) of the first transceiver 10 of the first wireless communication device S1 and the second transceiver 20 of the second wireless communication device S2. Then, a mode signal for setting the transmission state is acquired, and a capacity adjustment signal is generated based on the mode signal.

Specifically, during the transmission of the first wireless communication device S1 and the reception of the second wireless communication device S2, the capacity adjustment unit 39 increases the voltage of the capacity adjustment signal, and thereby the variable capacitance diodes 37h and 37p. Increase the capacity value. Then, the phase of the first transmission signal is adjusted, and the phase of the signal based on the sneak wave received by the second antenna 21 and the third antenna 51 at the portion combined with the first distribution signal is the first distribution. The phase is opposite to that of the signal (180 ° deviation). That is, the sneak wave is canceled out. In addition, during the transmission of the second wireless communication device S2 (second antenna 21) and the reception of the first wireless communication device S1, the capacity adjustment unit 39 sets the voltage of the capacity adjustment signal at the time of transmission of the first wireless communication device S1. Accordingly, the capacitance values of the variable capacitance diodes 37h and 37p are reduced. Then, the phase of the signal based on the sneak wave received by the first antenna 11 is adjusted, and the phase of the signal based on the sneak wave at the portion combined with the second distribution signal is the phase of the second distribution signal. And a reverse phase (180 ° deviation). That is, the sneak wave is canceled,
Next, a specific configuration example of the above-described interference suppression device 30 will be described with reference to FIG. Also in the present embodiment, as in the first embodiment, a ground plane 41 (in other words, a reflection plate) is provided on one surface of the planar rectangular dielectric substrate 40, and on the surface opposite to the ground plane installation surface in the dielectric substrate 40. A microstrip line 42 is disposed. The ground plane 41 and the microstrip line 42 arranged in parallel via the dielectric substrate 40 constitute a microstrip line.

  Three microstrip lines 42 are arranged on the dielectric substrate 40, and form a first power supply line 12, a second power supply line 22, and a third power supply line 52, respectively. One end of each power supply line 12, 22, 52 is located at the same long side end portion of the planar rectangular dielectric substrate 40, and is a power supply point 13, 33, 53, respectively. Monopole antennas 11, 21, 51 are mounted on the other ends of the power supply lines 12, 22, 52, respectively.

  Each of the power supply lines 12, 22, and 52 is, as a part thereof, located between the power supply lines 22 and 52 of the second wireless communication device S2 and the first power supply line 12 of the first wireless communication device S1. It has parallel parts 12a, 22a, 52 arranged in parallel with the adjacent power supply line with a predetermined interval. These parallel portions 12a, 22a, and 52a constitute a microstrip line type directional coupler 31. Note that the length of the parallel portions 12a, 22a, 52a (the length in the direction orthogonal to the interval direction) is λ / with respect to one of the wavelengths λ of the two wireless communication devices S1, S2. The length is set to about 4.

  The variable phase shifter 38 is mounted on a portion of the microstrip line 42 that constitutes the first feed line 12 between the first antenna 11 and the directional coupler 31. In the example shown in FIG. 9, the capacity adjustment unit 39 is provided separately from the dielectric substrate 40, and the wiring (for example, the microstrip line 42) that electrically connects the variable phase shifter 38 and the capacity adjustment unit 39. The illustration is omitted. However, a configuration in which the capacity adjustment unit 39 is mounted on the dielectric substrate 40 can also be adopted.

  Next, the interference suppression effect by the above-described interference suppression device 30 will be described.

  According to the interference suppression device 30 according to the present embodiment, two radio communications using one directional coupler 31 (coupling means) and a variable phase shifter 38 (adjusting means) with different operating frequencies and one of which is a diversity system. In the machines S1 and S2, interference caused by sneak waves can be suppressed in both directions. Therefore, it is possible to provide the interference suppression device 30 that can suppress interference caused by the sneak wave in both directions with a simple configuration while suppressing deterioration in communication quality.

  The inventor made a prototype of the interference suppression device 30 shown in FIG. 10 in which the antennas 11, 21, and 51 are mounted on the dielectric substrate 40, and measured the passage loss. The result is shown by a solid line in FIG. A broken line shown in FIG. 11 indicates a passage loss without the interference suppression device 30. As shown in FIG. 11, by providing the interference suppression device 30, the passage loss is reduced in both the first wireless communication device S1 (720 MHz band) and the second wireless communication device S2 (900 MHz band). Also from this, it is clear that communication quality deterioration was suppressed by interference suppression.

  In the present embodiment, each of the power supply lines 12, 22, 52 is configured as the microstrip line 42 on the same dielectric substrate 40, and is a microstrip line type formed by a part of each power supply line 12, 22, 52. A directional coupler 31 is employed. Therefore, the configuration of the interference suppression device 30 can be further simplified. In FIG. 10, the feed lines 12, 22, 52 are formed on the surface of the dielectric substrate 40 opposite to the ground plane 41, and the parallel portions 12 a, 22 a, 52 a are in a direction parallel to the surface of the dielectric substrate 40. An example in which the directional coupler 31 is formed in parallel is shown. However, the directional coupler 31 in which the dielectric substrate 40 is a multilayer substrate and the parallel portions 12a, 22a, and 52a are arranged in parallel in the thickness direction of the dielectric substrate 40 may be employed.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

  In this embodiment, the example which employ | adopts the microstrip line type directional coupler 31 as a coupling means was shown. However, a part of the first transmission signal transmitted from the first antenna 11 of the first wireless communication device S1 is extracted from the first power supply line 12, distributed to the second power supply line 22, and the second wireless communication device. If a part of the second transmission signal transmitted from the second antenna 21 of S2 can be extracted from the second feed line 22 and distributed to the first feed line 12, it is adopted as a coupling means. Can do. For example, a directional coupler 31 other than the microstrip line type may be employed. A capacitor that couples the first power supply line 12 and the second power supply line 22 can also be employed.

  In the present embodiment, an example in which the variable phase shifter 38 is employed in a configuration in which one of the two wireless communication devices S1 and S2 is a diversity wireless communication device is shown. However, as shown in FIG. 12, the variable phase shifter is used as the adjusting means even in the configuration in which both the first radio communication device S1 and the second radio communication device S2 are not of the diversity system (configuration having only one set of antenna and feed line). 38 can be adopted.

  In the present embodiment, in the configuration in which both the first wireless communication device S1 and the second wireless communication device S2 are not diversity systems (configuration having only one set of an antenna and a feeding line), the adjustment units 32 and 33 as adjustment means, and selection The example which employ | adopts the switches 34 and 35 and the selection signal production | generation part 36 as a means was shown. However, as shown in FIG. 13, in a configuration in which one of the two wireless communication devices S1 and S2 is a diversity wireless communication device, adjustment units 32 and 33 as adjustment means and a switch 34 as selection means. , 35 and a selection signal generation unit may be employed.

  In the present embodiment, an example in which adjustment means for adjusting at least the phase of the phase and the power level (amplitude) is provided in only one of the two wireless communication devices S1 and S2 is shown. However, in the two wireless communication devices S1 and S2 for transmission and reception, it is also possible to employ a configuration in which adjustment means are provided in the power supply line through which the transmission signal and the reception signal based on the sneak wave propagate. In FIG. 14 shown as an example, a variable phase shifter 38 is provided in each of the first feeding line 12 and the second feeding line 22 in a configuration in which both the first wireless communication device S1 and the second wireless communication device S2 are not of the diversity system. Yes. Further, the first power supply line 12 and the second power supply line 22 may be provided with adjustment units 32 and 33 as adjustment means and switches 34 and 35 as selection means, respectively.

DESCRIPTION OF SYMBOLS 11 ... 1st antenna 12 ... 1st feed line 21 ... 2nd antenna 22 ... 2nd feed line 30 ... Interference suppression apparatus 31 ... Directional coupler (coupling means)
32 ... 1st adjustment part (1st adjustment means)
33 ... 2nd adjustment part (2nd adjustment means)
34, 35 ... switch (selection means)
36... Selection signal generator (selection means)
38 ... Variable phase shifter (adjustment means)
42 ... microstrip line 51 ... third antenna 52 ... third feed line S1 ... first wireless communication device S2 ... second wireless communication device

Claims (9)

In the first wireless communication device and the second wireless communication device for transmission / reception that use frequencies different from each other, a sneak wave from the antenna of the first wireless communication device to the antenna of the second wireless communication device, and the second wireless communication An interference suppression device for suppressing interference due to a sneak wave from the antenna of the machine to the antenna of the first wireless communication device,
A part of the transmission signal transmitted from the antenna of the first wireless communication device is extracted from the power supply line of the first wireless communication device and transmitted to the power supply line of the second wireless communication device, and the second wireless communication A coupling means for extracting a part of the transmission signal transmitted from the antenna of the communication device from the power supply line of the second wireless communication device and transmitting it to the power supply line of the first wireless communication device;
At least one of the power supply lines of the first wireless communication device and the second wireless communication device is provided between the antenna connected to the power supply line and the coupling means, and the first wireless communication device and the second wireless communication device. Adjusting means for adjusting at least the phase and the power level of the signal transmitted through the power supply line according to the transmission timing of the wireless communication device,
The sneak wave transmitted from the antenna of the first wireless communication device and received by the antenna of the second wireless communication device is fed from the power supply line of the first wireless communication device by the coupling means to the power supply of the second wireless communication device. Offset by the signal transmitted to the line,
The sneak wave transmitted from the antenna of the second wireless communication device and received by the antenna of the first wireless communication device is fed from the power supply line of the second wireless communication device by the coupling means. An interference suppression apparatus, wherein the interference suppression apparatus is canceled by a signal transmitted to a line.   The adjusting means is provided between the antenna in the power supply line of the first wireless communication device and the connection point of the coupling means, and the antenna of the first wireless communication device transmits the sneak wave to the second wireless communication. When the antenna of the wireless communication device receives the signal, the transmission signal transmitted from the antenna of the first wireless communication device is adjusted, and the antenna of the second wireless communication device transmits the sneak wave of the wireless communication device of the first wireless communication device. The interference suppression device according to claim 1, wherein when the antenna receives, the received signal received by the antenna of the first wireless communication device is adjusted. As the adjustment means, first adjustment means for adjusting a transmission signal transmitted from the antenna of the first wireless communication device, and second adjustment means for adjusting a reception signal received by the antenna of the first wireless communication device. When,
When the antenna of the first wireless communication device transmits and the wraparound wave is received by the antenna of the second wireless communication device, the first adjustment means is selected, and the antenna of the second wireless communication device transmits Selecting means for selecting the second adjusting means when the antenna of the first wireless communication device receives the sneak wave;
The first adjustment means is transmitted from the antenna of the first wireless communication device, and the sneak wave received by the antenna of the second wireless communication device is transmitted from the power supply line of the first wireless communication device by the coupling means. Set to be canceled by the signal transmitted to the power supply line of the second wireless communication device,
The second adjustment means is transmitted from the antenna of the second wireless communication device, and the sneak wave received by the antenna of the first wireless communication device is transmitted from the power supply line of the second wireless communication device by the coupling means. The interference suppression device according to claim 2, wherein the interference suppression device is set so as to be canceled by a signal transmitted to the power supply line of the first wireless communication device. The adjusting means has a variable phase shifter for adjusting the phase;
The variable phase shifter is a transmission transmitted from the antenna of the first wireless communication device when the antenna of the first wireless communication device transmits and the wraparound wave is received by the antenna of the second wireless communication device. The received signal received by the antenna of the first wireless communication device when the phase of the signal is adjusted and the antenna of the second wireless communication device transmits and the wraparound wave is received by the antenna of the first wireless communication device The interference suppression device according to claim 2, wherein the phase of the interference suppression device is adjusted.   The interference suppressing apparatus according to claim 1, wherein the coupling unit is a 4-port directional coupler.   A part of the transmission signal extracted from the power supply line of the first wireless communication device by the directional coupler is output to the power supply point side of the power supply line of the second wireless communication device, and the second wireless communication device 6. The interference suppression apparatus according to claim 5, wherein a part of the transmission signal extracted from the power supply line is output to a power supply point side in the power supply line of the first wireless communication device. The second wireless communication device is a diversity wireless communication device having two sets of an antenna and a feeding line connected to the antenna,
The coupling means extracts a part of the transmission signal transmitted from the antenna of the first wireless communication device from the power supply line of the first wireless communication device and transmits the extracted signal to both power supply lines of the second wireless communication device. 6-port directional coupling for extracting a part of the transmission signal transmitted from the antenna of the second wireless communication device from the power supply line of the second wireless communication device and transmitting it to the power supply line of the first wireless communication device The interference suppression device according to claim 1, wherein the interference suppression device is a device.   A part of the transmission signal extracted from the power supply line of the first wireless communication device by the directional coupler is output to the power supply point side of the power supply line of the second wireless communication device, and the second wireless communication device The interference suppression apparatus according to claim 7, wherein a part of the transmission signal extracted from the power supply line is output to a power supply point side in the power supply line of the first wireless communication device. The power supply line of the first wireless communication device and the power supply line of the second wireless communication device are configured as microstrip lines with respect to the same dielectric substrate,
The directional coupler is configured as a microstrip line type directional coupler by a part of a feeding line of the first wireless communication device and a part of a feeding line of the second wireless communication device. Item 9. The interference suppression device according to any one of Items 5 to 8.

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