JP6028692B2 - Antenna device - Google Patents

Description

  The present invention has two stages: analog stage interference suppression for performing interference suppression by signal processing in a radio frequency band and digital stage interference suppression for performing interference suppression by digital signal processing after digitizing a signal after analog stage interference suppression. The present invention relates to an antenna device that suppresses interference.

  As a conventional antenna apparatus that performs interference suppression, for example, there is an antenna apparatus described in Patent Document 1. In the antenna device described in Patent Document 1, first, a reception signal in a radio frequency band is converted into N (N is a natural number) beam signals by a multi-beam forming circuit. Next, the reception signal level of the N beam signals output from the multi-beam forming circuit is detected, and M (M is a natural number) beam signals are selected based on the detection result. Subsequently, the M beam signals are frequency-converted by a down converter, and then converted to a digital signal by an analog-digital converter (hereinafter referred to as ADC). Finally, interference suppression processing is performed by digital signal processing. Thus, by selecting M beams from N beams, the number of downstream downconverters and ADCs can be reduced, and the scale of the digital unit in the final stage has been reduced.

JP 2000-244223 A

  Since the conventional antenna device selects a beam signal based on the received signal level of the beam signal, the noise power observed in the band increases depending on the beam signal band, and interference occurs when the level of the incoming interference wave is small. There was a problem that waves could not be detected and communication performance deteriorated. Further, when the power level of the interference wave is large, the signal after analog / digital conversion occupies most of the dynamic range, and there is a problem that the dynamic range of the desired wave component cannot be secured.

  The present invention has been made in order to solve the above-described problems. A beam signal is divided into predetermined frequency division units (hereinafter referred to as subchannels) after ADC, and level detection is performed using a received signal for each subchannel. The purpose of the present invention is to obtain an antenna device that can reduce the noise power observed in the band and improve the detection accuracy of interference waves compared to the case of detecting the received signal level with a beam signal. To do.

  Furthermore, this invention can improve the interference suppression performance of the analog stage by reducing interference by signal processing of the radio frequency signal for the beam signal based on the detection information, and can reduce the interference wave component to the ADC, An object of the present invention is to obtain an antenna device that can secure a desired wave component in an ADC dynamic range.

  The antenna device of the present invention includes a plurality of element antennas, an analog beam forming unit that combines signals received by the plurality of element antennas in a radio frequency band to form a plurality of beam signals, and the analog beam forming unit outputs In addition to a plurality of beam signals, a radio frequency band beam signal for communication is combined with a beam signal for interference wave suppression in which an amplitude phase is adjusted by a first excitation weight and output, and interference suppression is performed. An analog stage interference suppression unit that outputs a beam signal in a radio frequency band, a plurality of analog / digital conversion units that convert each of a plurality of beam signals output by the analog stage interference suppression unit into a digital signal, and the plurality Each of the digital signals converted by the analog-to-digital converter is divided into a plurality of subchannel signals in a predetermined frequency division unit. The amplitude phase of the demultiplexing filter bank and the plurality of subchannel signals divided by the demultiplexing filter banks are adjusted by the second excitation weight, and the communication beam signal is divided in predetermined frequency division units. A digital stage interference suppressor for synthesizing the digital signal and a combined filter bank for synthesizing a band of the digital signal divided by a predetermined frequency division unit synthesized by the digital stage interference suppressor and outputting a beam signal for communication And an interference suppression control unit that determines a first excitation weight and a second excitation weight from a plurality of subchannel signals divided by the plurality of demultiplexing filter banks.

  According to the present invention, the beam signal is divided into predetermined frequency division units after the ADC, and the level detection is performed with the reception signal for each subchannel. Therefore, compared with the case of the reception signal level detection with the beam signal. The noise power observed in the band can be reduced, and the interference wave detection accuracy can be improved.

  In addition, according to the present invention, interference suppression performance of the analog stage is improved by performing interference suppression on the beam signal by signal processing of the radio frequency signal based on the detection information of the interference wave, and the interference wave component to the ADC And the desired wave component in the ADC dynamic range can be secured.

It is a block diagram which shows an example of a structure of the antenna device of Embodiment 1 of this invention. It is a figure which shows the structural example of the interference suppression control part of the antenna apparatus of Embodiment 1 of this invention. It is a figure which shows the structural example of the analog stage interference suppression part of the antenna apparatus of Embodiment 1 of this invention. It is a figure which shows the structural example of the digital stage interference suppression part of the antenna apparatus of Embodiment 1 of this invention. It is a flowchart which shows an example of operation | movement of the antenna apparatus of Embodiment 1 of this invention. It is a block diagram which shows an example of a structure of the antenna device of Embodiment 2 of this invention. It is a figure which shows the structural example of the interference suppression control part of the antenna device of Embodiment 2 of this invention. It is a figure which shows the structural example of the analog stage interference suppression part of the antenna apparatus of Embodiment 2 of this invention. It is a flowchart which shows an example of operation | movement of the antenna device of Embodiment 2 of this invention.

  The antenna device according to the present invention includes an analog stage interference suppression that suppresses interference by analog signal processing in a radio frequency band, and a digital stage interference suppression that performs interference suppression by digital signal processing after digitizing the signal after analog stage interference suppression And two-stage interference suppression to improve the communication quality of the communication beam signal. Hereinafter, an example of the configuration and operation of the antenna device of the present invention will be described.

Embodiment 1 FIG.
The antenna apparatus according to Embodiment 1 of the present invention performs analog stage interference suppression that performs interference suppression by analog signal processing in a radio frequency band, and performs digital signal processing after performing digital signal processing after performing analog stage interference suppression. Two-stage interference suppression is performed, including digital stage interference suppression.

  1 is a block diagram showing an example of the configuration of an antenna device according to Embodiment 1 of the present invention. In FIG. 1, a plurality of receiving element antennas 1-1 to 1-K (K pieces, K is an arbitrary natural number) receive signals. The analog beam forming unit 2 combines the signals received by the plurality of element antennas 1-1 to 1-K in a radio frequency band and combines a plurality of beam signals B-1 to BN (N lines, where N is an arbitrary number). Natural number.). The analog stage interference suppression unit 3a uses a radio frequency band signal for communication (here, B-1) for the plurality of beam signals B-1 to BN output from the analog beam forming unit 2. In addition, a beam signal (in this case, B-2 to B-2) for suppressing interference waves, in which the amplitude and phase (hereinafter also referred to as amplitude phase) are adjusted by the first excitation weights W1-2 to W1-N. (B-N) are combined and output as a signal S1-1, and beam signals in a radio frequency band for interference wave suppression are output as signals S2-1 to SN-1. The plurality of analog-to-digital converters (ADC) 4-1 to 4-N are connected with the plurality of beam signals S1-1 to SN-1 output from the analog stage interference suppression unit 3a as inputs, and the analog beam signals Each is converted to a digital signal. The plurality of demultiplexing filter banks 5-1 to 5-N are connected to correspond to the ADCs 4-1 to 4-N, and each of the digital signals converted by the ADCs 4-n (n = 1 to N) has a predetermined frequency. Divided into a plurality of subchannel signals Cn-1 to CnM (here, divided into M signals, where M is an arbitrary natural number). The digital stage interference suppression unit 6 converts the plurality of subchannel signals Cn-1 to Cn-M divided by the plurality of demultiplexing filter banks 5-1 to 5-N into the second excitation weight W2-2. The amplitude and phase are adjusted by 1 to W2-N-M, and the communication beam signal is synthesized into digital signals F-1 to FM divided by a predetermined frequency division unit. The multiplexing filter bank 7 band-synthesizes the digital signals F-1 to FM divided by a predetermined frequency division unit synthesized by the digital stage interference suppressing unit 6 and outputs a communication beam signal. The interference suppression control unit 8a uses the first excitation of the analog stage interference suppression unit 3a used for adjusting the amplitude and phase of the signal from the plurality of subchannel signals divided by the plurality of demultiplexing filter banks 5-1 to 5-N. The weight and the second excitation weight of the digital stage interference suppression unit 6 are determined.

  Here, the first excitation weight and the second excitation weight each include a weight for adjusting the amplitude and the phase, and the second excitation weight is represented by a complex number.

  The beam signals before being input to the plurality of analog / digital conversion units 4-1 to 4-N are beam signals in the radio frequency band, and the radio frequency band beam signal for communication and the radio for interference suppression are used. A distinction can be made between beam signals in the frequency band. Each of the analog / digital conversion units 4-1 to 4-N converts an analog beam signal obtained by down-conversion (down converter not shown) from the radio frequency band to the baseband into a digital beam signal. To do. Therefore, analog stage interference suppression is processed in the radio frequency band, and digital stage interference suppression is processed in the baseband.

  FIG. 2 is a diagram illustrating a configuration example of an interference suppression control unit of the antenna device according to the first embodiment of the present invention. In FIG. 2, the subchannel monitor unit 81 of the interference suppression control unit 8a uses a plurality of subchannel signals C-1-1-1 to C-N-M divided by a plurality of demultiplexing filter banks 5-1 to 5-N. Output the measured power values PC-1-1 to PC-N-M of a predetermined frequency division unit, and interfere by level detection from the power values PC-1-1 to PC-N-M of the predetermined frequency division unit. A wave is detected, and interference wave detection signals DC- 2-1 to DC-N-M in a predetermined frequency division unit and interference wave detection signals DB 1-2 to DB 1 -N in a plurality of beam signal units are output. The analog interference suppression control unit 82 is configured to generate an analog stage based on the interference detection signals DB1-2 to DB1-N and the power values PC-1-1 to PC-N-M in units of a plurality of beam signals from the subchannel monitor unit 81. First excitation weights W1-2 to W1-N that allow the interference suppression unit 3a to adjust the amplitude and phase of a plurality of beam signals are set. The digital interference suppression control unit 83 receives a plurality of subchannel signals C- 1-1 to C-N-M divided by the plurality of demultiplexing filter banks 5-1 to 5 -N and a predetermined number of sub-channel monitoring units 81. A second excitation weight W2-2 that causes the digital stage interference suppression unit 6 to adjust the amplitude and phase of the plurality of subchannel signals based on the interference wave detection signals DC-2-1 to DC-NM in frequency division units. 1 to W2-N-M are set.

  In this way, in the interference suppression control unit 8a, the analog excitation suppression control unit 82 sends the first excitation weight to the analog stage interference suppression unit 3a, and the digital interference suppression control unit 83 sends the second excitation weight to the digital stage interference suppression unit. 6 is output.

  Next, an outline of the operation of the antenna device according to the first embodiment of the present invention will be described based on each configuration of FIG.

  First, in FIG. 1, an analog beam forming unit 2 synthesizes signals received by the element antennas 1-1 to 1-K in a radio frequency band and converts them into N beam signals B-1 to BN. To do. Here, it is assumed that one desired wave arrives and (N-1) waves of interference waves arrive. The arrival directions of a total of N (N waves) radio waves are estimated by the MUSIC (Multiple Signal Classification) method, which is a known technique, and each beam is directed to each N wave. Further, it is assumed that the interference wave arrives at the same frequency as the desired wave in the radio frequency band. The received signal may be input to each of the receiving element antennas 1-1 to 1-K via a reflecting mirror.

  The analog stage interference suppressing unit 3a transmits the beam signals B-1 to BN based on the first excitation weights W1-2 to W1-N designated by the analog interference suppression control unit 82 of the interference suppression control unit 8a. Interference suppression is performed by performing signal processing in the band.

  Here, FIG. 3 is a diagram illustrating a configuration example of the analog stage interference suppressing unit of the antenna device according to the first embodiment of the present invention. The analog stage interference suppression unit 3a includes first signals indicating weights for adjusting the amplitude and phase from the analog interference suppression control unit 82 of the interference suppression control unit 8a and the beam signals B-1 to BN from the analog beam forming unit 2. Excitation weights W1-2 to W1-N are input. In FIG. 3, power distributors 31a-n (2 ≦ n ≦ N) distribute the beam signal B-n into a distribution signal Sn-1 and a distribution signal Sn-2. The distribution signal Sn-1 (2 ≦ n ≦ N) is output from the analog stage interference suppression unit 3a to the ADC 4-n without adjusting the amplitude and phase in order to be used for interference suppression by subsequent digital signal processing. The distribution signal Sn-2 has the amplitude and phase first excitation weights W1-2 to W1-N as adjustment weights, and the digital phase shifter 32-n (2 ≦ n ≦ N) changes the phase to W1-n ( p), then the digital attenuator 33-n (2 ≦ n ≦ N) adjusts the amplitude with the weight of W1-n (a). The first power combiner 34 combines the distribution signals whose amplitude and phase are adjusted. The second power combiner 35 combines the signal combined by the first power combiner 34 and the beam signal B-1 and outputs the combined signal S1-1 to the ADC 4-1. The first power combiner 34 and the second power combiner 35 may be configured as one power combiner.

  In FIG. 1, ADC4-n (1 ≦ n ≦ N) samples and quantizes each signal S1-1 to SN-1 output from the analog stage interference suppression unit 3a, and converts the analog signal to a digital signal. To do.

  The demultiplexing filter bank 5-n (1.ltoreq.n.ltoreq.N) has the frequency of each digital signal converted by the ADC 4-n (1.ltoreq.n.ltoreq.N) in a predetermined frequency division unit, here, M subchannels. To divide. Here, it is assumed that the demultiplexing filter bank 5-n (1 ≦ n ≦ N) divides the Sn−1 digital signal into subchannel signals Cn−1 to CnM.

  The digital stage interference suppression unit 6 performs amplitude and phase for each subchannel based on the second excitation weights W2-2-1 to W2-NM specified from the digital interference suppression control unit 83 of the interference suppression control unit 8a. Are adjusted and synthesized into subchannel signals F-1 to FM.

  4 is a diagram illustrating a configuration example of a digital stage interference suppressing unit of the antenna device according to the first embodiment of the present invention. In FIG. 4, a multiplier 61-nm (2 ≦ n ≦ N, 1 ≦ m ≦ M) is input from the digital interference suppression control unit 83 of the interference suppression control unit 8a to the subchannel signal C-nm. Product the second excitation weight. Next, the adder 62-m (1 ≦ m ≦ M) adds the signal multiplied by the second excitation weight and the subchannel signal C-1-m.

  The multiplexing filter bank 7 band-synthesizes and outputs the subchannel signals F-1 to FM divided into M of the communication beam signals output from the digital stage interference suppression unit 6.

  An outline of the operation of the interference suppression control unit 8a will be described based on each configuration of FIG.

  In FIG. 2, the sub-channel monitor unit 81 has a predetermined frequency division measured from a plurality of sub-channel signals C-1-1 to C-N-M divided by a plurality of demultiplexing filter banks 5-1 to 5-N. Outputs a power value in units, detects subchannels on which interference waves arrive by level detection from power values PC-1-1 to PC-N-M in predetermined frequency division units, and interferes with predetermined frequency division units Interference wave detection signals DC-2-1 to DC-N-M indicating that a wave has been detected and interference wave detection signals DB1-2 to DB1-N indicating that an interference wave has been detected in units of a plurality of beam signals are output. To do.

  The analog interference suppression control unit 82 performs analog processing based on the interference wave detection signals DB1-2 to DB1-N and power values PC-1-1-1 to PC-N-M in units of a plurality of beam signals from the subchannel monitor unit 81. First excitation weights W1-2 to W1-N that allow the interference suppression unit 3 to adjust the amplitude and phase of a plurality of beam signals are set.

  Here, when the interference wave detection signals DB1-2 to DB1-N are input, the analog interference suppression control unit 82 is input from the subchannel monitor unit 81 while changing the excitation weight of the output amplitude and phase. For example, the power values are set to the first excitation weights W1-2 to W1-N that minimize the combined power. Since no interference wave has arrived in the beam signal whose interference wave detection signal does not indicate detection, the attenuation of each digital attenuator 33-n (2 ≦ n ≦ N) is set so as not to operate the analog stage interference suppression unit 3a. Control to set the amount to the maximum value.

  The digital interference suppression control unit 83 receives a plurality of subchannel signals C- 1-1 to C-N-M divided by the plurality of demultiplexing filter banks 5-1 to 5 -N and a predetermined number of sub-channel monitoring units 81. A second excitation weight W2-2 that causes the digital stage interference suppression unit 6 to adjust the amplitude and phase of the plurality of subchannel signals based on the interference wave detection signals DC-2-1 to DC-NM in frequency division units. 1 to W2-N-M are set.

  Here, when receiving the interference detection signals DC-2-1 to DC-N-M, the digital interference suppression control unit 83 uses the second excitation weight W2-2-1 for suppressing interference at the digital stage. Calculate ~ W2-N-M. For example, the excitation weight is determined so that the combined power of each subchannel is minimized. The excitation weight of each subchannel is output to the digital stage interference suppressing unit 6.

  FIG. 5 is a flowchart showing an example of the operation of the antenna device according to the first embodiment of the present invention. In FIG. 5, the operation of the antenna device will be described separately for the case where no interference wave is detected and the case where an interference wave is detected.

  First, a flow when no interference wave is detected will be described. The antenna elements 1-1 to 1-K receive signals (step ST1), and the analog beam forming unit 2 forms a plurality of beam signals (step ST2).

  First, when no interference wave is detected in the beam signal or the subchannel signal, the interference suppression and digital stage interference suppression unit 6 of the analog stage interference suppression unit 3a does not operate, and the signal passes as it is. That is, a plurality of beam signals are digitized in ADCs 4-1 to 4-N (step ST3), and are divided into subchannel units in the demultiplexing filter banks 5-1 to 5-N (step ST4). The subchannel monitor unit 81 performs power measurement in units of subchannels (step ST5). If it is determined that no interference wave is detected in the beam signal or the subchannel signal, analog stage interference suppression (step ST6) and digital stage interference suppression are performed. (Step ST8) is determined to be unnecessary (No). In the multiplexing filter bank 7, the digital signals divided in subchannel units are band-synthesized and output as digital signals (step ST11).

  Further, when an interference wave is detected in the beam signal or the subchannel signal, the interference suppression of the analog stage interference suppression unit 3a and the digital stage interference suppression unit 6 operates. That is, after processing from step ST1 to step ST4, the subchannel monitor unit 81 performs power measurement for each subchannel (step ST5), and if it is determined that an interference wave is detected, analog stage interference suppression (step ST6). The digital stage interference suppression (step ST8) is determined to be necessary (Yes).

  First, when an interference wave is detected in the beam signal by power measurement in units of subchannels, the analog interference suppression unit 3 is operated (step ST6). For example, the amplitude and phase of the beam signals B-2 to BN are adjusted so that the combined power of the beam signals B-1 to BN in the radio frequency band in which the interference wave is detected is minimized (step ST7). ). Here, the amplitude and phase are adjusted and repeated from the power measurement (step ST5), and the first excitation weights W1-2 to W1-N are determined so that the combined power has the minimum amplitude and phase.

  Next, when an interference wave is detected in the subchannel signal, the digital stage interference suppression unit 6 is operated (step ST8). For example, the second excitation weights W2-2-1 to W2-NM are calculated so that the combined power for each subchannel is minimized (step ST9). For example, using a power inversion standard (for example, Non-Patent Document 1: Nobuyoshi Kikuma, “Adaptive Antenna Technology”, Ohm Publishing, published on October 10, 2003, p. 85-91), which is a known technique, A second excitation weight is calculated from the digital signal in units of subchannels. Each of the second excitation weights is multiplied by the subchannel signal and added in units of subchannels (step ST10). Thereafter, the multiplexing filter bank 7 band-synthesizes the digital signals divided in units of subchannels and outputs the digital signals (step ST11).

  As described above, according to the first embodiment of the present invention, after the digitized beam signal is divided into subchannels by the demultiplexing filter bank, the subchannel monitor unit detects the interference wave in units of subchannels. Therefore, the detection accuracy of the interference wave can be improved.

  Further, according to the first embodiment of the present invention, the excitation weight for adjusting the amplitude and phase in beam signal units is set based on the power value of the interference wave detected in subchannel units. The interference suppression performance of the beam signal in the stage interference suppression unit can be improved.

  Further, according to the first embodiment of the present invention, interference wave components input to the ADC can be reduced by performing interference suppression in the analog stage, so that a desired wave component within the dynamic range of the ADC can be ensured. it can.

  Furthermore, according to Embodiment 2 of the present invention, analog stage interference suppression performance can be improved by performing analog stage interference suppression based on subchannel unit power information, and interference waves input to the ADC can be reduced. Can do.

  Note that analog stage interference suppression is not limited to only one subchannel, but may be a plurality of subchannels.

Embodiment 2. FIG.
In Embodiment 1 of the present invention, analog stage interference suppression for performing interference suppression by signal processing in a radio frequency band, and digital stage interference for performing interference suppression by digital signal processing after digitizing a signal after analog stage interference suppression is performed. An antenna apparatus that performs two-stage interference suppression with suppression has been described.

  Next, in the second embodiment of the present invention, not only the analog stage interference suppression based on the power information of each subchannel shown in the first embodiment and the digital stage interference suppression by digital signal processing are performed, but also the radio frequency band. By performing the analog stage interference suppression in the entire beam signal band in the first stage of the ADC shown in the first embodiment of the present invention, interference suppression in the entire beam signal band and interference using only the band in which interference arrives are performed. What is performed in the two stages of suppression will be described.

  FIG. 6 is a block diagram showing an example of the configuration of the antenna device according to the second embodiment of the present invention. In FIG. 6, the analog stage interference suppressing unit 3 b uses a radio frequency band signal for communication (here, B-1) for the plurality of beam signals B- 1 to B-N output from the analog beam forming unit 2. And the amplitude and phase (hereinafter also referred to as amplitude phase) adjusted by the first excitation weights W1-2 to W1-N and the third excitation weights W3-2 to W3-N. A radio frequency band beam signal for suppression (in this case, B-2 to B-N) is synthesized and output as a signal S1-1, and a radio frequency band beam signal for interference wave suppression is output as a signal S2. Output as -1 to SN-1. The interference suppression control unit 8b includes a plurality of subchannel signals divided by the plurality of demultiplexing filter banks 5-1 to 5-N and signal amplitudes from S1-1 to SN-1 output from the analog stage interference suppression unit 3b. The first excitation weight of the analog stage interference suppression unit 3b, the third excitation weight, and the second excitation weight of the digital stage interference suppression unit 6 to be used for phase adjustment are determined.

  Here, the first to third excitation weights include weights for adjusting the amplitude and the phase, respectively, and the second excitation weight is represented by a complex number.

  Further, in FIG. 6, a plurality of receiving element antennas 1-1 to 1-K, an analog beam forming unit 2, a plurality of analog / digital converting units (ADC) 4-1 to 4-N, and a plurality of demultiplexing filter banks 5 are provided. −1 to 5-N, the digital stage interference suppressing unit 6 and the multiplexing filter bank 7 are configured in the same manner as the components with the same reference numerals shown in FIG. 1 as the antenna device according to the first embodiment of the present invention. In order to operate and function, individual descriptions are omitted.

  Note that the first excitation weight received by the analog stage interference suppression unit 3b is received from the interference suppression control unit 8a as shown in FIG. 3 in the analog stage interference suppression unit 3a of the first embodiment of the present invention. The difference is that the interference suppression control unit 8b receives the third excitation weight together. Further, the second excitation weight received by the digital stage interference suppression unit 6 is received from the interference suppression control unit 8a as shown in FIG. 4 in the digital stage interference suppression unit 6 of the first embodiment of the present invention. Although the difference is that it is received from the interference suppression control unit 8b, the configuration, function, and operation of the digital stage interference suppression unit 6 are the same.

  FIG. 7 is a diagram illustrating a configuration example of an interference suppression control unit of the antenna device according to the second embodiment of the present invention. In FIG. 7, the beam signal monitoring unit 84 of the interference suppression control unit 8b includes power values PB-1 to PB in units of a plurality of beam signals measured from the signals S1-1 to SN-1 output from the analog stage interference suppression unit 3b. -N is output, interference waves are detected by level detection from the power values PB-1 to PB-N in units of a plurality of beam signals, and interference wave detection signals DB2-2 to DB2-N in units of a plurality of beam signals are obtained. Output. The second analog interference suppression control unit 85 suppresses analog stage interference based on the interference detection signals DB2-2 to DB2-N and power values PB-1 to PB-N in units of a plurality of beam signals from the beam signal monitoring unit 84. Third excitation weights W <b> 3-2 to W <b> 3 -N that allow the unit 3 b to adjust the amplitude and phase of the plurality of beam signals are set.

  In FIG. 7, the subchannel monitor unit 81, the analog interference suppression control unit 82, and the digital interference suppression control unit 83 are components having the same reference numerals shown in FIG. 2 as the antenna device according to the first embodiment of the present invention. Since it is configured, operates, and functions in the same manner as above, individual descriptions are omitted.

  Thus, the interference suppression control unit 8b receives the first excitation weight from the internal analog interference suppression control unit 82 to the analog stage interference suppression unit 3b, and receives the third excitation weight from the second analog interference suppression control unit 85. The second excitation weight is output from the digital interference suppression control unit 83 to the digital stage interference suppression unit 6 to the analog stage interference suppression unit 3b and, similarly to the interference suppression control unit 8a of the first embodiment.

  Next, an outline of the operation of the antenna device according to the second embodiment of the present invention will be described based on each configuration of FIG. Here, the operations of analog stage interference suppression section 3b and interference suppression control section 8b having different configurations from those of the antenna apparatus according to Embodiment 1 of the present invention will be described.

  In FIG. 6, the analog stage interference suppression unit 3b outputs the beam signals B-1 to BN to the first excitation weights W1-2 to W1-N designated by the analog interference suppression control unit 82 of the interference suppression control unit 8b. And interference suppression is performed by performing signal processing in the radio frequency band based on the third excitation weights W3-2 to W3-N. Here, the analog stage interference suppression unit 3b performs interference suppression in the entire beam signal band in the first stage, and two-stage interference suppression using only the band in which interference arrives in the second stage.

  Here, FIG. 8 is a diagram illustrating a configuration example of the analog stage interference suppressing unit of the antenna device according to the second embodiment of the present invention. The analog stage interference suppression unit 3b includes first weights indicating beam signals B-1 to BN from the analog beam forming unit 2 and weights for adjusting amplitude and phase from the analog interference suppression control unit 82 of the interference suppression control unit 8b. Excitation weights W1-2 to W1-N and third excitation weights W3-2 to W3-N are input. In FIG. 8, the power distributor 31b-n (2 ≦ n ≦ N) distributes the beam signal B-n into three distribution signals Sn-1, Sn-2, and Sn-3. The distribution signal Sn-1 (2 ≦ n ≦ N) is output from the analog stage interference suppression unit 3b to the ADC 4-n without adjusting the amplitude and phase in order to be used for interference suppression by subsequent digital signal processing. Similarly to the first embodiment, the distribution signal Sn-2 is a digital phase shifter 32-n (2 ≦ n ≦ N) with the amplitude and phase first excitation weights W1-2 to W1-N as adjustment weights. ) Adjusts the phase with the weight of W1-n (p), and then the digital attenuator 33-n (2 ≦ n ≦ N) adjusts the amplitude with the weight of W1-n (a). The first power combiner 34 combines the distribution signals whose amplitude and phase are adjusted. The second power combiner 35 combines the signal combined by the first power combiner 34 and the beam signal B-1 and outputs the combined signal S1-1 to the ADC 4-1. The first power combiner 34 and the second power combiner 35 may be configured as one power combiner. In addition, the distribution signal Sn-3 has the amplitude and phase third excitation weights W3-2 to W3-N as adjustment weights, and the digital phase shifter 36-n (2 ≦ n ≦ N) changes the phase to W3−3. The digital attenuator 37-n (2 ≦ n ≦ N) then adjusts the amplitude with the weight of W3-n (a) with the weight of n (p). The third power combiner 38 combines the distribution signals whose amplitude and phase are adjusted. The fourth power combiner 39 combines the signal combined by the third power combiner 38 and the beam signal B-1, and outputs the combined signal to the ADC 4-1. The third power combiner 38 and the fourth power combiner 39 may be configured as one power combiner. Further, the first to fourth power combiners may be configured as one power combiner.

  An outline of the operation of the interference suppression control unit 8b will be described based on each configuration of FIG. Here, the operations of the beam signal monitoring unit 84 and the second analog interference suppression control unit 85 added to the configuration of the interference suppression control unit 8a of the antenna device according to the first embodiment of the present invention will be described.

  In FIG. 7, the beam signal monitor unit 84 performs power measurement over the entire bandwidth of each beam signal. Interference detection signals DB2-2 to DB2- indicating that interference has been detected by detecting the power values PB-1 to PB-N of the beam signals from which interference has been detected and the power values PB-1 to PB-N. N is output to the second analog interference suppression control unit 85.

  When the interference detection signal is input, the second analog interference suppression control unit 85 observes the combined value of the power of the beam signal input from the beam signal monitor unit 84 while adjusting the amplitude and phase. Third excitation weights W3-2 to W3-N for adjusting the amplitude and phase to be minimized are set. On the other hand, when the interference detection signal is not input, the attenuation amount of the digital attenuators 37-2 to 37-N is set to the maximum value so that the interference suppression is not operated.

  FIG. 9 is a flowchart showing an example of the operation of the antenna device according to the second embodiment of the present invention. In FIG. 9, the operation of the antenna device will be described separately for the case where no interference wave is detected and the case where an interference wave is detected. Here, what is given the same step number as the flowchart showing the operation of the antenna apparatus according to the first embodiment of the present invention in FIG. Step ST5 to step ST11 are the same as the flowchart showing the operation of the antenna device according to the first embodiment of the present invention, so the description of the flowchart of FIG. 7 is partially omitted.

  First, a flow when no interference wave is detected will be described. The antenna elements 1-1 to 1-K receive signals (step ST1), and the analog beam forming unit 2 forms a plurality of beam signals (step ST2).

  When no interference wave is detected in the beam signal or the subchannel signal, the interference suppression of the analog stage interference suppression unit 3b and the digital stage interference suppression unit 6 does not operate, and the signal passes as it is. The beam signal monitor unit 84 performs power measurement in units of beam signals (step ST13), and the subchannel monitor unit 81 performs power measurements in units of subchannels (step ST5) to detect interference waves in the beam signals and subchannel signals. If determined not to be performed, it is determined that analog stage interference suppression (step ST14 and step ST6) and digital stage interference suppression (step ST8) are unnecessary (No), respectively. In the multiplexing filter bank 7, the digital signals divided in subchannel units are band-synthesized and output as digital signals (step ST11).

  Further, when an interference wave is detected in the beam signal or the subchannel signal, the interference suppression of the analog stage interference suppression unit 3b and the digital stage interference suppression unit 6 operates. That is, after processing from step ST1 to step ST2 in the same manner as the flowchart of FIG. 7, the beam signal monitor unit 84 performs power measurement in units of beam signals (step ST13), and when it is determined that an interference wave is detected, The analog stage interference suppression (step ST14) is determined to be necessary (Yes), and the second analog interference suppression control unit 85 observes the combined power while changing the third excitation weight of the beam signal, and the combined power is minimized. 3 is set (step ST15). Thereafter, from step ST3 to step ST11, the analog stage interference suppression (step ST6) and the digital stage interference suppression (step ST8) are determined to be necessary (Yes) and processed in the same manner as the flowchart of FIG.

  As described above, according to the second embodiment of the present invention, as in the first embodiment of the present invention, after the digitized beam signal is divided into subchannels by the demultiplexing filter bank, the subchannel monitor unit Since the interference wave is detected in units of sub-channels, the detection accuracy of the interference wave can be improved.

  Further, according to Embodiment 2 of the present invention, similarly to Embodiment 1 of the present invention, the amplitude and phase are adjusted in units of beam signals based on the power value of the interference wave detected in units of subchannels. Since the excitation weight is set, the interference suppression performance of the beam signal in the analog stage interference suppression unit can be improved.

  Further, according to the second embodiment of the present invention, as in the first embodiment of the present invention, the interference wave component input to the ADC can be reduced by performing the interference suppression in the analog stage, so that the dynamics of the ADC The desired wave component within the range can be ensured.

  Furthermore, according to Embodiment 2 of the present invention, analog stage interference suppression performance can be improved by performing analog stage interference suppression based on power information in units of subchannels, as in Embodiment 1 of the present invention. Interference waves input to the ADC can be reduced.

  Further, according to the second embodiment of the present invention, the beam signal monitoring unit measures the power of each beam signal in the radio frequency band, and operates the second analog interference suppression control unit based on the power value. Since the analog stage interference suppression for the entire beam signal is performed, the amount of interference wave input to the ADC can be suppressed without using the digital stage, and the ADC can be used when a strong power interference wave arrives. It is possible to contribute to ensuring the dynamic range of the desired wave signal.

  Note that analog stage interference suppression is not limited to only one subchannel, but may be a plurality of subchannels, as in the first embodiment of the present invention.

  1-1 to 1-K Multiple receiving element antennas, 2 Analog beam forming units, 3a, 3b Analog stage interference suppressing units, 4-1 to 4-N Multiple analog / digital converting units (ADC), 5-1 5-N multiple demultiplexing filter banks, 6 digital stage interference suppression units, 7 multiplexing filter banks, 8a and 8b interference suppression control units, 31a and 31b power dividers, 32-2 to 32-N digital phase shifters, 33-2 to 33-N digital attenuator, 34 first power combiner, 35 second power combiner, 36-2 to 36-N digital phase shifter, 37-2 to 37-N digital attenuator, 38 third power combiner, 39 fourth power combiner, 61-2-1 to 61-NM multiplier, 62-1 to 61-M adder, 81 subchannel monitor unit, 82 analog interference suppression Control unit, 83 digital Interference suppression control unit, 84 beam signal monitor unit, 85 second analog interference suppression controller.

Claims (6)

A plurality of element antennas;
An analog beam forming unit that forms a plurality of beam signals by combining signals received by the plurality of element antennas in a radio frequency band;
The multiple beam signals output by the analog beam forming unit are combined with a radio frequency band signal for communication and a radio frequency band beam signal for interference wave suppression in which the amplitude phase is adjusted with a first excitation weight. An analog stage interference suppression unit that outputs a beam signal in the radio frequency band for interference suppression, and
A plurality of analog-digital converters for converting each of the plurality of beam signals output from the analog stage interference suppressing unit into digital signals;
A plurality of demultiplexing filter banks for dividing each of the digital signals converted by the plurality of analog / digital conversion units into a plurality of subchannel signals in a predetermined frequency division unit;
The amplitude phase of the plurality of subchannel signals divided by the plurality of demultiplexing filter banks is adjusted by a second excitation weight, and the communication beam signal is synthesized into the digital signal divided by the predetermined frequency division unit. A digital stage interference suppression unit that
A multiplexing filter bank that band-synthesizes the digital signal divided by the predetermined frequency division unit synthesized by the digital stage interference suppression unit and outputs the beam signal for communication;
An antenna apparatus comprising: an interference suppression control unit that determines the first excitation weight and the second excitation weight from the plurality of subchannel signals divided by the plurality of demultiplexing filter banks. The antenna device according to claim 1,
The interference suppression control unit
The power measurement value of the predetermined frequency division unit measured from the plurality of subchannel signals is output, and an interference wave is detected by level detection from the power measurement value, and the predetermined frequency division unit and the plurality of beam signals are detected. A subchannel monitor unit for outputting each unit interference wave detection signal;
The first excitation weight in the analog stage interference suppression unit is determined based on the power measurement value in the predetermined frequency division unit in the subchannel monitor unit and the interference wave detection signal in the plurality of beam signal units. The second excitation weight in the digital stage interference suppression unit is determined based on the analog interference suppression control unit, the plurality of subchannel signals, and the interference wave detection signal of the predetermined frequency division unit in the subchannel monitor unit An antenna device comprising a digital interference suppression control unit. The antenna device according to claim 2, wherein
The interference suppression control unit
Outputs a power measurement value of the beam signal measured from the plurality of beam signals from the analog stage interference suppression unit, detects an interference wave by level detection from the power measurement value, and detects an interference wave of the plurality of beam signals A beam signal monitor for outputting a signal;
A second analog interference suppression control unit that determines a third excitation weight in the analog stage interference suppression unit based on interference wave detection signals of the plurality of beam signals in the beam signal monitor unit and the power measurement value. ,
The analog stage interference suppression unit is an interference suppression radio frequency band in which an amplitude phase is adjusted by the first excitation weight and the third excitation weight with respect to the plurality of beam signals in the radio frequency band for interference suppression. The antenna apparatus outputs the beam signal in the radio frequency band for interference suppression while combining and outputting the beam signal in the radio frequency band for communication. The antenna device according to claim 2 or 3,
The analog interference suppression control unit causes the analog stage interference suppression unit to adjust the amplitude phases of the plurality of beam signals to minimize the combined power of the predetermined frequency division unit in which the interference wave is detected. An antenna device for determining a first excitation weight. The antenna device according to claim 2 or 3,
The digital interference suppression control unit is configured to reduce the second excitation weight that minimizes a combined power of the predetermined frequency division unit based on a power measurement value of the predetermined frequency division unit measured from the plurality of subchannel signals. Determine the antenna device. The antenna device according to claim 3, wherein
The second analog interference suppression control unit determines the third excitation weight that minimizes the combined power of the beam signals by causing the analog stage interference suppression unit to adjust the amplitude phases of the plurality of beam signals. Antenna device.

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