JP5846211B2 - Interference wave suppressing device and interference wave suppressing method - Google Patents

Description

  The present invention relates to an interference wave suppressing device and an interference wave suppressing method for suppressing interference waves in wireless communication.

  In addition to reducing the side lobe and increasing the directivity of the main lobe, there are techniques to suppress the interference wave using multiple antennas as a technique to suppress the interference wave incident from the side lobe of the wireless communication antenna ( For example, Patent Document 1). Here, the side lobe means a ring-shaped portion of directivity other than the main lobe where the directivity of the antenna is the maximum direction.

  In the sidelobe canceller described in Patent Document 1, the sum signal of two antenna outputs that receive a desired wave and the amplitude of the difference signal are aligned, and after the adaptive filter is applied to the difference signal, the sum signal and the adaptive filter The received signal in which the interference wave is suppressed is generated by taking the difference from the output signal.

Japanese Patent Laid-Open No. 11-88208

  If the above-described technique for increasing the directivity of the main lobe is used to suppress the interference wave, there is a problem that the configuration of the antenna becomes complicated and becomes large. Further, in the technology for suppressing interference waves using the difference between two received signals as described in Patent Document 1, two antennas must be prepared to receive one desired wave. There was a problem.

  An object of the present invention is to provide an interference wave suppressing device and an interference wave suppressing method capable of solving the above-described problems.

In order to solve the above-described problem, an interference wave suppressing apparatus according to the present invention includes an interference wave having a frequency different from a desired wave of two or more antennas whose directing directions are respectively directed to two or more different communication destinations. enter the respective output signals including bets, respectively distributes to the number corresponding to the number of the antennas, a plurality of distributor corresponding to the number of the antennas, the direction of the desired wave to the distributor is distributed A first combiner that calculates and outputs a signal corresponding to a difference between a signal corresponding to the output signal of the received antenna and a signal corresponding to the output signal of the antenna directed in a direction different from the direction of the desired wave; The sum of the signal corresponding to the output signal of the antenna directed in the direction of the desired wave distributed by the distributor and the signal corresponding to the output signal of the antenna directed in a direction different from the direction of the desired wave Different corresponding second combiner for the output signal calculated by the that, with the distributor direction of the corresponding signal and the desired wave to the output signal of the antenna oriented in the direction of the desired wave among the output signals distributed Each of the output signals distributed by the distributor after adjusting the phase of at least one of the signals corresponding to the output signal of the antenna directed in the direction to set the signal corresponding to the sum to the maximum amplitude and adjusting the phase And adjusting the amplitude of at least one of the signal corresponding to the output signal of the antenna directed in the direction of the desired wave and the signal corresponding to the output signal of the antenna directed in a direction different from the direction of the desired wave And an adjustment unit that minimizes the interference wave in the signal corresponding to.

Also, the interference wave suppression method inputs each output signal including a desired wave of two or more antennas whose directing directions are respectively directed to two or more different communication destinations and an interference wave having a frequency different from the frequency of the desired wave. Then, each of the antennas is distributed in a number corresponding to the number of the antennas, and the signal corresponding to the distributed output signal of the antenna directed in the direction of the desired wave and the direction of the antenna directed in a direction different from the direction of the desired wave A signal corresponding to the difference from the signal corresponding to the output signal is calculated and output, and the signal corresponding to the output signal of the antenna directed in the direction of the distributed desired wave is directed in a direction different from the direction of the desired wave was then calculates and outputs a signal corresponding to the sum of the corresponding signal to the output signal of the antenna, signals corresponding to the antenna output signal directed in the direction of the desired wave among the output signals distributed Wherein the maximum amplitude of adjusting at least one of the phase signal corresponding to the sum of the desired signal corresponding to the antenna output signal directed in a direction different from the direction of, after adjusting the phase, the distribution The amplitude of at least one of the signal corresponding to the output signal of the antenna directed in the direction of the desired wave and the signal corresponding to the output signal of the antenna directed in a direction different from the direction of the desired wave among each output signal Adjust and minimize the interference wave in the signal corresponding to the difference.

  According to the interference wave suppressing device of the present invention, it is possible to suppress the interference wave using one relatively small and simple antenna for each desired wave.

It is a block diagram which shows the basic composition of the interference wave suppression apparatus concerning 1st embodiment of this invention. It is a block diagram which shows the structural example of the interference wave suppression apparatus concerning 1st embodiment of this invention. FIG. 3 is a block diagram illustrating a configuration example of an interference canceller in FIG. 2. 4 is a flowchart showing an example of adjustment operations of an amplitude adjuster and a phase adjuster in FIG. 3. It is a block diagram which shows the structural example of the interference wave suppression apparatus concerning 2nd embodiment of this invention. FIG. 6 is a block diagram illustrating a configuration example of an interference canceller in FIG. 5. It is a flowchart which shows an example of adjustment operation of the amplitude adjuster and phase adjuster of FIG. FIG. 6 is an explanatory diagram for explaining a signal flow when the interference wave suppressing device of FIG. 5 is controlled using an external control device.

First Embodiment Hereinafter, an embodiment of an interference wave suppressing device according to the present invention will be described with reference to the drawings. First, a basic configuration of an interference wave suppressing device 100 according to the first embodiment of the present invention will be described with reference to FIG. The interference wave suppressing apparatus 100 shown in FIG. 1 is installed between an antenna and a receiver in a point-to-point wireless communication system, and receives an interference wave incident from a side lobe of the wireless communication antenna. It is a device for suppressing. Here, the point-to-point wireless communication means wireless communication performed between a pair of communication devices facing one-to-one.

The interference wave suppression device 100 shown in FIG. 1 includes interference suppression means 110. The interference suppression unit 110 inputs the output signals of two or more antennas whose directing directions are respectively directed to two or more different communication destinations. In other words, the interference suppression means 110 includes a signal corresponding to the output signal of the antenna directed in the direction of a certain one communication wave (referred to as a desired wave) and an output of the antenna directed in a direction different from the direction of the desired wave. A signal corresponding to the signal is input. Here, the two or more antennas whose directing directions are respectively directed to two or more different communication destinations are installed such that each antenna is adjusted in the directivity direction in a direction facing a predetermined communication destination antenna. Is used when performing point-to-point wireless communication with a predetermined communication destination.
Also, the positional relationship between the antenna directed in the direction of the desired wave and the antenna directed in a direction different from the direction of the desired wave is different from the direction of the desired wave for the antenna directed in the direction of the desired wave. The radio wave directed to the antenna directed to becomes an interference wave, and for the antenna directed to a direction different from the direction of the desired wave, the radio wave directed to the antenna directed to the desired wave direction can be an interference wave. Have a positional relationship of. Then, the interference suppression unit 110 includes a signal corresponding to the output signal of the antenna directed in the direction of the desired wave and a signal corresponding to the output signal of the antenna directed in a direction different from the direction of the desired wave among the output signals. A signal corresponding to the difference is output to the receiver of the desired wave.

With the above configuration, the interference wave suppression device 100 according to the present invention monitors the output signal of the antenna directed in a direction different from the direction of the desired wave, and “subtracts” from the antenna output signal directed in the direction of the desired wave. By performing the “corresponding process”, the signal component of the interference wave included in the output signal of the antenna directed in the direction of the desired wave is reduced. Here, “processing corresponding to subtraction” has two meanings including the following first and second arithmetic processing, that is, subtraction processing and addition processing. In other words, the first calculation process is to subtract an interference wave having the same phase (that is, a phase difference of 0 degree or 360 degrees) from the interference wave included in the output signal of the antenna directed to the desired wave. Here, the interference wave to be subtracted is an interference wave included in the output signal of the antenna directed in a direction different from the direction of the desired wave.
The second calculation process is a process of adding an interference wave having an opposite phase (that is, a phase difference of 180 degrees) to the interference wave included in the output signal of the antenna directed to the desired wave. Here, the interference wave to be added is an interference wave included in the output signal of the antenna directed in a direction different from the direction of the desired wave. In this way, the interference wave suppressing device 100 uses the output signal of the antenna directed to the desired wave and the output signal of the antenna directed to a direction different from the direction of the desired wave to The side lobe can be null (that is, the sensitivity in the direction of the interference wave can be reduced). Thus, by using the interference wave suppressing device 100, for example, it is not necessary to lower the side lobe level over a wide area, and an antenna having a simple configuration can be used. Also, when removing the interference wave signal from the received signal of the desired wave antenna for a certain communication destination, since the received signal of the antenna for the other communication destination is used, a plurality of antennas are connected to the same communication destination. There is no need to prepare, and only one antenna is required for each communication destination. It is also possible to use a plurality of antennas for one communication destination.
Interference wave suppressing apparatus 100 suppresses an interference wave received by an antenna directed to a desired wave by using the same interference wave received by an antenna directed in a direction different from the direction of the desired wave. der Ru (i.e. Ru der those reduce interference signals by combining offset the same interference wave each other received by the two antennas). That is, the desired wave and interference wave, not good a radio signal of a different frequency.

Second Embodiment Next, a second embodiment of the interference wave suppression device 100 shown in FIG. 1 will be described with reference to FIGS. FIG. 2 is a block diagram showing a configuration example of an interference wave suppression device 100a as a second embodiment of the interference wave suppression device 100 shown in FIG. In FIG. 2, the interference wave suppression device 100a includes distributors 2-1 and 2-2, interference cancellers 3-1 and 3-2, and a receiver 5-1 connected to antennas 1-1 and 1-2, respectively. And 5-2 connected to 5-2 and 5-2, respectively. The interference wave suppressing device 100a is connected to the interference cancellers 3-1 and 3-2, and when performing phase adjustment and amplitude adjustment in the interference cancellers 3-1 and 3-2, the interference canceller 3-1 and An output unit 17 that displays 302 outputs is provided. For example, the output unit 17 can indicate the outputs of the interference cancellers 3-1 and 302 by numerical values or graphs.

  The antennas 1-1 and 1-2 are, for example, parabolic antennas or the like, and are installed to perform point-to-point communication with opposite stations in different directions. The distributors 2-1 and 2-2 receive the signals received by the antennas 1-1 and 1-2 to the D port (desired signal port) and U port (interference signal port) of the interference cancellers 3-1 and 3-2, respectively. Distribute. That is, the divider 2-1 receives the reception signal output from the antenna 1-1, distributes it to the D port of the interference canceller 3-1, and the U port of the interference canceller 3-2, and outputs it. The distributor 2-2 receives the reception signal output from the antenna 1-2, distributes the received signal to the D port of the interference canceller 3-2 and the U port of the interference canceller 3-1, and outputs the distributed signal. Here, the distributors 2-1 and 2-2 do not have to be equally distributed. For example, the distribution amount to the U port may be reduced.

  The interference cancellers 3-1 and 3-2 process the received signals of the two antennas 1-1 and 1-2, remove the interference, extract only the desired signal, and output it from the Δ port. From each Δ port of the interference cancellers 3-1 and 3-2, a signal input to each D port is used as a desired wave signal, and a signal input from each U port is used as an interference wave signal. A signal corresponding to the difference is output. In addition, from each Σ port of the interference cancellers 3-1 and 3-2, the signal input to each D port is used as a desired wave signal, and the signal input from each U port is used as an interference wave signal. Signals corresponding to the sum of the signals (that is, the sum of the signals) are output.

  The receiver 5-1 receives the signal received by the antenna 1-1 as a desired wave, and is selectively connected to the Δ port and the Σ port of the interference canceller 3-1 through the switch 4-1. Is done. That is, the receiver 5-1 receives one of the signals of each port by switching the switch 4-1. Similarly, the receiver 5-2 receives the signal received by the antenna 1-2 as a desired wave, and selects it as the Δ port and Σ port of the interference canceller 3-2 via the switch 4-2. Connected. That is, the receiver 5-2 receives one of the signals of each port by switching the switch 4-2.

  The switches 4-1 and 4-2 may be switched manually, or a control signal output from a control device such as a computer built in or connected to the interference wave suppression device 100a (not shown). You may make it carry out according to.

Referring to FIG. 3, there is shown a detailed configuration of the interference cancellers 3-1 and 3-2 shown in FIG. Here, the interference cancellers 3-1 and 3-2 have the same internal configuration. In FIG. 3, the amplitude adjuster 6 adjusts the amplitude of the signal input to the U port. The phase adjuster 7 inputs the signal input to the U port via the amplitude adjuster 6 and adjusts the phase thereof. The amplitude adjuster 6 and the phase adjuster 7 constitute an adjustment unit 67. The signal whose amplitude and phase are adjusted is distributed by the distributor 8-2 and input to the Δ synthesizer 9 and the Σ synthesizer 10.
The signal input to the D port is distributed by the distributor 8-1 and input to the Δ combiner 9 and the Σ combiner 10. The Δ synthesizer 9 performs a D port signal-U port signal (that is, subtracting the signal from the U port from the signal from the D port) and outputs the result.
The synthesizer 10 performs the D port signal + U port signal (that is, the addition process of the signal from the D port and the signal from the U port) and outputs the result.

The amplitude and phase adjustment in the amplitude adjuster 6 and the phase adjuster 7 may be performed manually or according to a control signal output from a control device such as a computer (not shown). May be. The amplitude can be adjusted by the amplitude adjuster 6 by using, for example, an attenuator capable of adjusting the attenuation rate continuously or stepwise and setting the attenuation rate manually or automatically. Note that the case of automatic setting will be described later with reference to FIG.
The phase adjustment by the phase adjuster 7 can be performed, for example, by manually or automatically setting the phase shift value using a phase shifter (that is, a phase shifter) capable of adjusting the phase continuously or stepwise. . The amplitude and phase adjustment values performed on the amplitude adjuster 6 and the phase adjuster 7 change the attenuation rate and the phase shift value of the amplitude adjuster 6 and the phase adjuster 7 when manually adjusting. It can be set by manually changing the on / off state of the switch to be turned on and the state of the variable element. In the case of automatic adjustment, voltage control and motor control (that is, mechanical control) control the on / off state of the switch that changes the attenuation factor and phase shift value of the amplitude adjuster 6 and the phase adjuster 7 and the state of the variable element. This can be done by changing. In the case of automatic adjustment, each control value is set in the amplitude adjuster 6 and the phase adjuster 7 or in an external control device (not shown) provided in the interference cancellers 3-1 and 3-2. Is stored in a non-volatile memory or the like.

Next, operations of the interference cancellers 3-1 and 3-2 shown in FIG. 3 will be described with reference to FIG.
In the process shown in FIG. 4, the amplitude adjuster 6 and the phase adjuster 7 in the interference cancellers 3-1 and 3-2 are adjusted. Here, a case where the operator performs manual adjustment will be described.

First, the operator switches the switch 4-1 in FIG. 2 to connect the Σ port of the interference canceller 3-1 to the receiver 5-1. In this state, the operator adjusts the phase adjuster 7 of the interference canceller 3-1 while observing the Σ port of the interference canceller 3-1 with the receiver 5-1, and outputs the output ( That is, the adjustment value of the phase adjuster 7 is set so that the input level of the receiver 5-1 is maximized (step S11). Here, the output of the interference canceller 3-1 (that is, the input level of the receiver 5-1) is displayed on the output unit 17. Therefore, the operator changes the adjustment value of the phase adjuster 7 while observing the result output to the output unit 17, and outputs the interference canceller 3-1 (that is, the input level of the receiver 5-1). The adjustment ends when becomes the maximum. Thus, the adjustment value of the phase adjuster 7 is set when the output of the interference canceller 3-1 (that is, the input level of the receiver 5-1) becomes maximum.
In this case, the desired wave received by the antenna 1-1 via the distributor 2-1 (that is, the desired wave for the antenna 1-1 and the receiver 5-1) is connected to the D port of the interference canceller 3-1. ) Signal and an interference wave signal are input. However, the signal level of the interference wave input to the D port is a sufficiently small value determined according to the directivity of the antenna 1-1 as compared with the signal level of the desired wave. On the other hand, an interference wave received by the antenna 1-2 via the distributor 2-2 (that is, a desired wave for the antenna 1-2 and the receiver 5-2) is provided to the U port of the interference canceller 3-1. And the signal of the desired wave are input. However, the signal level of the desired wave input to the U port is a sufficiently small value determined according to the directivity of the antenna 1-2 as compared with the signal level of the interference wave.

As an example, the frequencies of the desired wave and the interference wave are slightly different, and the ratio between the main lobe and the side lobe of the antenna 1-1 and the antenna 1-2 is 9: 1 (the maximum value of the main lobe: the maximum value of the side lobe). Further, the distribution ratio of the distributor 2-1 and the distributor 2-2 to the D port and the U port is 9: 1 (D port distribution ratio: U port distribution ratio).
In this case, assuming that the magnitude of the output signal of the antenna 1-1 is 1, the magnitude of the desired wave input to the D port of the interference canceller 3-1 is 0.81 = 0.9 × 0.9, and the interference The magnitude of the wave is 0.09 = 0.1 × 0.9. On the other hand, assuming that the magnitude of the output signal of the antenna 1-2 is 1, the magnitude of the desired wave input to the U port of the interference canceller 3-1 is 0.01 = 0.1 × 0.1, and the interference wave Is 0.09 = 0.9 × 0.1.
Therefore, from the Σ port of the interference canceller 3-1, the 0.81 desired wave input from the D port and the 0.01 desired wave input from the U port are added in consideration of the phase difference. , 0.09 interference wave input from the D port and 0.09 interference wave input from the U port are added in consideration of the phase difference.
In this example, the 0.09 phase difference input from the U port and the 0.09 phase difference input from the D port are adjusted to the same phase (that is, the phase difference is 0 degree or 360 degrees). If the input desired wave of 0.01 is ignored, the desired wave of 0.81 and the interference wave of 0.18 = 0.09 + 0.09 are output from the Σ port of the interference canceller 3-1. The result of adding and is output.
Here, the desired wave and the interference wave output from the Σ port of the interference canceller 3-1 are strengthened or weakened by the phase difference. However, in this example, since the frequency of the desired wave and the frequency of the interference wave are slightly different, the signal level output from the Σ port of the interference canceller 3-1 changes with a frequency difference between different frequencies. Will (ie fluctuate).
Therefore, the operator adjusts the maximum value of the changing signal level output from the Σ port in the receiver 5-1 to be the maximum so that the interference wave included in the input signal of the D port and the input signal of the U port The phase difference of the interference wave contained in can be made substantially the same phase.

Next, the operator switches the switch 4-1 to connect the Δ port of the interference canceller 3-1 to the receiver 5-1. Then, the operator, while observing the Δ port interference canceller 3-1 receiver 5-1 to adjust the amplitude adjuster 6 of the interference canceller 3-1, sets the adjustment value of the amplitude adjuster 6 ( Step S12). Here, the output of the interference canceller 3-1 (that is, the input level of the receiver 5-1) is displayed on the output unit 17. Thus, the operator, while viewing the results that are output to the output unit 17, by changing the adjustment value of the amplitude adjuster 6, and terminates the adjustment. Accordingly, the adjustment value of the amplitude adjuster 6 is set.
In this case, the signal of the desired wave and the signal of the interference wave received by the antenna 1-1 via the distributor 2-1 are input to the D port of the interference canceller 3-1. An interference wave signal and a desired wave signal received by the antenna 1-2 via the distributor 2-2 are input to the U port of the interference canceller 3-1. However, the phase of the interference wave input to the D port and the phase of the interference wave input to the U port are adjusted to be approximately the same in step S11. Using the above example, when the desired wave of 0.01 input from the U port is ignored, the desired wave of 0.81 input from the D port and D A signal obtained by subtracting the 0.09 interference wave input from the U port from the 0.09 interference wave input from the port is output. That is, when the 0.09 interference wave input from the U port minus the 0.09 interference wave input from the D port is zero, the Δ port of the interference canceller 3-1 Thus, the desired wave of 0.81 input from is output without including the interference wave. Here, when the amplitude of the 0.09 interference wave input from the D port matches the amplitude of the 0.09 interference wave input from the U port, the amplitude is adjusted by the amplitude adjuster 6. Is not necessary. On the other hand, if they do not match, the amplitude is adjusted by the amplitude adjuster 6 so that the 0.09 interference wave input from the D port and the 0.09 interference wave input from the U port are efficiently obtained. Can cancel each other.

  Next, the operator switches the switch 4-2 to connect the Σ port of the interference canceller 3-2 to the receiver 5-2. Then, the operator adjusts the phase adjuster 7 of the interference canceller 3-2 while observing the Σ port of the interference canceller 3-2 with the receiver 5-2, and outputs the interference canceller 3-2 (that is, the receiver 5). The adjustment value of the phase adjuster 7 is set so that (−2 input level) is maximized (step S13). The operation in step S13 is the same as that in step S11. Here, the output of the interference canceller 3-2 (that is, the input level of the receiver 5-2) is displayed on the output unit 17. Therefore, the operator changes the adjustment value of the phase adjuster 7 while looking at the result output to the output unit 17, and outputs the interference canceller 3-2 (that is, the input level of the receiver 5-1). The adjustment ends when becomes the maximum. Thus, the adjustment value of the phase adjuster 7 is set when the output of the interference canceller 3-2 (that is, the input level of the receiver 5-2) is maximized.

Next, the operator switches the switch 4-2 to connect the Δ port of the interference canceller 3-2 to the receiver 5-2. Then, the operator, while observing the Δ port interference canceller 3-2 receiver 5-2 to adjust the amplitude adjuster 6 of the interference canceller 3-2, sets the adjustment value of the amplitude adjuster 6 ( Step S14). The operation in step S14 is the same as that in step S12. Here, the output of the interference canceller 3-2 (that is, the input level of the receiver 5-2) is displayed on the output unit 17. Thus, the operator, while viewing the results that are output to the output unit 17, by changing the adjustment value of the amplitude adjuster 6, and terminates the adjustment. Accordingly, the adjustment value of the amplitude adjuster 6 is set.

In the above processing, by adjusting the phase so that the output signal of the Σ port becomes the maximum in steps S11 and S13, the interference wave included in the input signal of the D port and the interference wave included in the input signal of the U port The adjustment value of the phase adjuster 7 can be set so that the phase difference approaches the minimum. Further, by adjusting the output signal amplitude of Δ port in step S12 and S14, the residuals when subtracting the interference waves included from interference wave included in the input signal of the D port of an input signal U port The size can be reduced. That is, by adjusting the phase so that the output signal of the Σ port is maximized, and by adjusting the output signal amplitude of Δ ports, are input to the D port using an interference signal that is input to the U port Further, the effect of removing the interference component in the desired signal can be maximized.

  The above adjustment can be automatically performed by a predetermined control device, or can be manually performed by a person. In addition, the above adjustment usually needs to be performed only once when the system is installed.

In the point-to-point wireless communication, the link of the antenna 1-1 is assumed to be the link 1, the link of the antenna 1-2 is assumed to be the link 2, and the interference suppression operation for the link 1 will be described as follows. In other words, the link 2 signal received by the antenna 1-1 and the link 2 signal received by the antenna 1-2 can be made in phase by the operation of step S11. Next, it is possible to obtain a difference by equalizing the signal of the link 2 received by the antenna 1-1 and the signal of the link 2 received by the antenna 1-2 by the operation of step S12. Therefore, the interference of the link 2 to the antenna 1-1 can be efficiently removed.
As described above, the embodiment according to the present invention has the following effects.

  The first effect is that the side lobes in the interference link direction are nulled to eliminate interference, so that it is not necessary to reduce the side lobes over a wide area, and the antenna configuration can be simplified.

  The second effect is that interference can be removed and the SNR (signal to noise ratio) can be improved, so that the required antenna gain can be reduced and a small antenna can be used.

  The third effect is that there is no decrease in transmission capacity because, for example, adjustment for interference removal usually only needs to be performed at the time of system installation, for example, it is not necessary to insert a pilot in a transmission signal during communication.

Third Embodiment Next, a third embodiment of the interference wave suppressing device 100 shown in FIG. 1 will be described with reference to FIGS. FIG. 5 is a block diagram showing a configuration example of an interference wave suppression device 100b as a third embodiment of the interference wave suppression device 100 shown in FIG. In the interference wave suppressing apparatus 100b, an interference canceller is further devised to cope with N links in point-to-point wireless communication. In FIG. 3, the interference wave suppressing apparatus 100b includes N distributors 11-1 to 11-N and N interference cancellers 12-1 to 12 connected to N antennas 1-1 to 1-N, respectively. -N, and N switches 13-1 to 13-N connected to N receivers 14-1 to 14-N, respectively.

  The distributors 11-1 to 11-N distribute the reception signals of the antennas 1-1 to 1-N to the interference cancellers 11-1 to 11-N. For example, the distributor 11-1 receives the reception signal of the antenna 1-1, distributes it to the D port of the interference canceller 12-1, and each U port of the interference cancellers 12-2 to 12 -N and outputs it. . Further, for example, the distributor 11-2 receives the reception signal of the antenna 1-2, and receives the D port of the interference canceller 12-2 and the U ports of the interference cancellers 12-1 and 12-3 to 12-N. To distribute to and output. Further, for example, the distributor 11 -N receives the reception signal of the antenna 1 -N, and receives the D port of the interference canceller 12 -N and the U ports of the interference cancellers 12-1 to 12-(N−1). To distribute to and output. Further, the interference cancellers 12-1 to 12-N process the signals of the antennas 1-1 to 1-N to remove the interference and extract the signals of the desired links.

  FIG. 6 shows the configuration of one of the interference cancellers 12-1 to 12-N. The interference cancellers 12-1 to 12-N have the same internal configuration. Each interference canceller 12-1 to 12-N shown in FIG. 6 includes (N-1) amplitude adjusters 6-1 to 6- (N-1) and (N-1) phase adjusters 7. -1-7- (N-1), synthesizer 15, distributors 8-1 and 8-2, Δ synthesizer 9 and Σ synthesizer 10. In addition, the same code | symbol is attached | subjected to the structure same as what was shown in FIG.2 and FIG.3. Each interference canceller 12-1 to 12-N has one D port and N-1 U ports, and each U port is input to an amplitude adjuster 6-1 to 6- (N-1). It is connected. The amplitude adjusters 6-1 to 6- (N-1) have a function equivalent to that of the amplitude adjuster 6 described above. The outputs of the amplitude adjusters 6-1 to 6- (N-1) are connected to the inputs of the phase adjusters 7-1 to 7- (N-1), respectively. The phase adjusters 7-1 to 7- (N-1) have a function equivalent to that of the phase adjuster 7 described above. The signals whose amplitude or phase has been adjusted by the amplitude adjusters 6-1 to 6- (N-1) and the phase adjusters 7-1 to 7- (N-1) are synthesized by the synthesizer 15. The output of the combiner 15 is distributed to the Δ combiner 9 and the Σ combiner 10 by the distributor 8-2. On the other hand, the signal at the D port is distributed to the Δ combiner 9 and the Σ combiner 10 by the distributor 8-1. The Δ synthesizer 9 outputs a difference (that is, a difference) between the two inputs. The synthesizer 10 outputs the sum (that is, the sum) of the two inputs.

  Next, referring to FIG. 7, adjustment of amplitude adjusters 6-1 to 6- (N-1) and phase adjusters 7-1 to 7-7 in interference cancellers 12-1 to 12-N shown in FIG. The adjustment operation of-(N-1) will be described. Here, an external control device (not shown) is used, and the outputs of the receivers 14-1 to 14-N are monitored by the control device, while the interference cancellers 12-1 to 12-N and the switches 13-1 to 13- are monitored. A case where each adjustment value is set by controlling N will be described.

  First, the external control device initializes the variable n to 1 (step S21). Here, the variable n is a loop variable used in the loop processing of steps S22 to S25.

  Next, the external control device outputs the phase adjusters 7-1 to 7- (N-1) of the interference canceller 12-n while observing the Σ port of the interference canceller 12-n with the receiver 14-n. Are adjusted in order so as to be maximized (step S22).

Next, an external control device, the amplitude adjuster 6-1~6- (N-1) the order in the interference canceller 12-n while observing the Δ port interference canceller 12-n by the receiver 14-n Adjust to.

  Next, the external control device adds 1 to the variable n (step S24), and when the variable n is N or less (that is, in the case of “no” in step S25), executes the processing after step S22. Therefore, the external control device performs the processes of steps S22 and S23 on the interference canceller 12-1 when n = 1, and the interference cancellers 12-2 to 12-12 when n = 2 to N. The processes of steps S22 and S23 are repeated for -N. Then, when the variable n becomes N + 1 (that is, when step S25 becomes “yes”), the external control device ends the process.

  Next, with reference to FIG. 7, the operation when the link of the antenna 1-n in the point-to-point wireless communication is the link n (n = 1 to N) will be described. First, the signal of each link n (n = 2 to N) received by the antenna 1-1 by the operation of step S22 and each link n (n = 2) received by each antenna 1-n (n = 2 to N). ˜N) can be in phase. Next, the signal of each link n (n = 2 to N) received by the antenna 1-1 by the operation of step S23 and each link n (n = 2) received by each antenna 1-n (n = 2 to N). ˜N) can be made equal in amplitude and the difference taken. Therefore, interference of each link n (n = 2 to N) to the antenna 1-1 can be suppressed. Thereafter, the processing of steps S22 and S23 is executed for each link n (n = 2 to N), so that each link n (n = 1 to N) to antennas 1-2 to 1 to N, where Interference (excluding links of the own antennas 1-2 to 1 to N) can be suppressed.

An example of a signal flow when the interference wave suppressing device 100b shown in FIG. 5 is controlled using an external control device will be described with reference to FIG. In FIG. 8, the same components as those shown in FIG. In the example illustrated in FIG. 8, the external control device 16 transmits signals corresponding to the magnitudes (for example, amplitude values) of the signals output from the switches 13-1 to 13-2 to the receivers 14-1 to 14-14. Input from -n. The signals input from the receivers 14-1 to 14-n may be analog signals having a voltage value corresponding to the amplitude value, for example, or in a predetermined format representing a value corresponding to the amplitude value. It may be a digital signal. Further, the external control device 16 outputs a signal for adjusting and setting the amplitude and phase to each adjustment unit 67 in each interference canceller 12-1 to 12-N. Further, the external control device 16 outputs a signal for switching the connection state of the switches 13-1 to 13-N. In such a connection state, the external control device 16 switches each of the switches 13-1 to 13-N and switches each of the switches 13-1 to 13-2 input from the receivers 14-1 to 14-n. Based on the signal corresponding to the magnitude of the output signal, a signal for adjusting and setting the amplitude and phase is output to each adjustment unit 67.
That is, the control device 16 sets the adjustment value of the phase adjuster 7 so that the output of the interference canceller 3-2 (that is, the input level of the receiver 5-2) is maximized. The control device 16 sets the adjustment value of the amplitude adjuster 6 so that the output of the interference canceller 3-2 (that is, the input level of the receiver 5-2) is minimized.

  As described above, according to the interference wave suppressing device according to the second embodiment of the present invention, in point-to-point wireless communication in which N points using N antennas that are adjacent or adjacent to each other are used as communication destinations. By using a simple and small antenna, interference between the links can be reduced.

  Further, according to the interference wave suppression devices of the first embodiment and the second embodiment according to the present invention, when a plurality of antennas having side lobes are used, signals of different links are received and interference between the links is caused. This problem can be improved by using a small antenna with a simple configuration.

Fourth Embodiment The embodiment of the interference wave suppressing device according to the present invention is not limited to the above. For example, in the interference cancellers 3-1 and 3-2 shown in FIG. 3, the amplitude and phase are adjusted for the interference signal input from the U port, but in addition to or instead of the D port The amplitude and / or phase may be adjusted with respect to the desired signal input from.

In the process shown in FIG. 4 or 7, the order of phase adjustment and amplitude adjustment is reversed, or after adjusting one of the phases or amplitudes for all or some of the antennas, The other of the phase and the amplitude may be adjusted with respect to some or some of the antennas. In addition, the interference wave suppressing device 100a and the interference wave suppressing device 100b can incorporate a control circuit for adjustment described above as an external control device.

Sixth Embodiment Further, instead of monitoring the reception levels of the receivers 5-1, 5-2 and 14-1 to 14-N, a switch 4-in the interference wave suppressing device 100a or the interference wave suppressing device 100b. An electronic circuit or the like for monitoring the output signal levels of 1, 4-2 and 13-1 to 13-N may be provided.

  This application claims priority based on Japanese Patent Application No. 2011-237595 for which it applied to Japan on October 28, 2011, and uses the content here.

  According to the interference wave suppressing apparatus according to the present invention, in a point-to-point communication or the like, an interference wave is suppressed using one relatively small and simple antenna for each desired wave.

DESCRIPTION OF SYMBOLS 100 Interference wave suppression apparatus 100a Interference wave suppression apparatus 100b Interference wave suppression apparatus 110 Interference suppression means 1-1, 1-2, 1-N Antenna 2-1, 2-2, 11-1, 11-2, 11-N Distributor 3-1, 3-2, 12-1, 12-2, 12-N Interference canceller 4-1, 4-2, 13-1, 13-2, 13-N Switch 5-1, 5-2 , 14-1, 14-2, 14-N receiver 6, 6-1, 6- (N-1) amplitude adjuster 7, 7-1, 7- (N-1) phase adjuster 8-1, 8-2 Distributor 9 Δ Synthesizer 10 Σ Synthesizer 15 Synthesizer

Claims (2)

Enter the respective output signal including an interference wave having a frequency different from 2 or more different directivity direction to the communication destination is 2 or more antennas oriented respectively desired wave and the frequency of the desired wave, the number of the antenna A plurality of distributors corresponding to the number of antennas, each distributing to a corresponding number;
Corresponds to the difference between the signal corresponding to the output signal of the antenna directed in the direction of the desired wave distributed by the distributor and the signal corresponding to the output signal of the antenna directed in a direction different from the direction of the desired wave. A first synthesizer that calculates and outputs a signal;
Corresponding to the sum of the signal corresponding to the output signal of the antenna directed in the direction of the desired wave distributed by the distributor and the signal corresponding to the output signal of the antenna directed in a direction different from the direction of the desired wave A second synthesizer that calculates and outputs a signal to be output;
In the signals corresponding to antenna output signal directed to a direction different from the direction of the corresponding signal and the desired wave to the output signal of the antenna oriented in the direction of the desired wave among the output signals the distributor is distributed After adjusting at least one of the phases and setting the signal corresponding to the sum to the maximum amplitude and adjusting the phase, the output signal of the antenna directed in the direction of the desired wave among the output signals distributed by the distributor An adjustment unit that adjusts the amplitude of at least one of the corresponding signal and the signal corresponding to the output signal of the antenna directed in a direction different from the direction of the desired wave, and minimizes the interference wave in the signal corresponding to the difference ; ,
The interference wave suppression apparatus provided with the interference suppression part which has. Enter the respective output signal including an interference wave having a frequency different from 2 or more different directivity direction to the communication destination is 2 or more antennas oriented respectively desired wave and the frequency of the desired wave, the number of the antenna Distribute each to the corresponding number,
A signal corresponding to a difference between a signal corresponding to the output signal of the antenna directed in the direction of the distributed desired wave and a signal corresponding to the output signal of the antenna directed in a direction different from the direction of the desired wave is calculated. Output,
The signal corresponding to the sum of the signal corresponding to the output signal of the antenna directed in the direction of the desired wave and the signal corresponding to the output signal of the antenna directed in a direction different from the direction of the desired wave is calculated. Output
Among the distributed output signals, at least one phase of a signal corresponding to the output signal of the antenna directed in the direction of the desired wave and a signal corresponding to the output signal of the antenna directed in a direction different from the direction of the desired wave , The signal corresponding to the sum is set to the maximum amplitude, the phase is adjusted, and the signal corresponding to the output signal of the antenna directed in the direction of the desired wave among the distributed output signals and the desired wave at least one of adjusting the amplitude to minimize the interference wave in the signal corresponding to the difference, interference suppression method of the signals corresponding to the antenna output signal directed in a direction different directions.

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