JP2006157588A - Wireless receiver - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the calculation amount of a weighting factor while maintaining high-quality reception characteristics. <P>SOLUTION: A plurality of FFT calculators are arranged to a plurality of receivers respectively including an antenna element. The FFT calculator divides the received signal received with the corresponding receiver into signals in plural frequency bands by Fourier transformation and outputs the signals. The weighting factors respectively corresponding to each of the signals in the same frequency band outputted from each of a plurality of the FFT calculators are acquired from a weighting factor storage and multiplied to each of the signals in the same frequency band. The signals are synthesized. When the change of the composite signal satisfies a prescribed weighting factor update reference by monitoring the change of the composite signal, a weighting factor corresponding to the same frequency band is calculated in each FFT calculator by using each of the signals in the same frequency band outputted from a plurality of the FFT calculators. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a wireless reception device.

The adaptive array receiver calculates a weight for each received signal based on the received signals received by a plurality of antenna elements, weights each received signal using the calculated weight, and synthesizes these weighted received signals. . According to this, a good reception characteristic can be obtained even if the frequency selective fading characteristic differs for each path. When such an adaptive array receiving apparatus is used in a multi-carrier transmission system or the like, first, the received signal received by each antenna element is divided into signals of a plurality of frequency bands. Next, a weight is calculated for each subcarrier in the same frequency band, each subcarrier is weighted using the calculated weight, and these weighted subcarriers are combined. This is performed for each frequency band.
JP 2000-332666 A

  However, calculation of the weight requires an enormous amount of calculation, and calculating the weight every reception increases the calculation load.

  In the conventional proposed method (see Patent Document 1), when the power level of the combined signal is detected and the power level is reduced, or when the error rate of the combined signal is detected and the error rate is increased. Although a technique for recalculating the weights is shown, this conventional proposed method divides a received signal into a plurality of frequency bands and performs processing for each frequency band as used in a multi-carrier transmission method or the like. No consideration is given to the weight calculation in the system.

  The present invention has been made to solve the above-described problem, and an object of the present invention is to provide a radio reception apparatus that can reduce the amount of calculation while maintaining high-quality reception characteristics.

  According to one aspect of the present invention, a wireless reception device includes a plurality of reception units each including an antenna element, and a plurality of reception units arranged corresponding to the plurality of reception units, and a plurality of reception signals received by the corresponding reception units by Fourier transform. A plurality of FFT (Fast Fourier Transform) computing units that divide and output the signals in frequency bands; a weighting factor storage unit that stores a weighting factor corresponding to each of the plurality of frequency bands for each FFT computing unit; The weighting coefficient corresponding to each signal of the same frequency band output from each of the plurality of FFT calculation units is acquired from the weighting factor storage unit and multiplied, and the signal of the same frequency band multiplied by the weighting factor is obtained. Weight synthesis means for synthesizing the signals, and changes in the synthesized signal generated by the weight synthesis means, and the changes in the synthesized signal satisfy a predetermined weight coefficient update criterion. Transmission path change monitoring means for determining whether or not to add, and when the change of the composite signal satisfies the predetermined weight coefficient update criterion, the signals of the same frequency band output from the plurality of FFT operation units And a weighting factor calculation unit that calculates a weighting factor corresponding to the same frequency for each FFT operation unit and stores the calculated weighting factor in the weighting factor storage unit.

  According to the present invention, the amount of calculation can be reduced while maintaining high quality reception characteristics.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(First embodiment)
FIG. 1 shows a configuration example of an adaptive array antenna radio receiving apparatus according to the present embodiment.

  The plurality of antenna elements 101-1 to 101-n in this adaptive array antenna radio receiving apparatus receive radio signals (for example, OFDM symbols) by the multicarrier transmission scheme. Radio signals received by the antenna elements 101-1 to 101-n are converted into electrical analog signals, and further converted into digital signals by AD conversion (see FIG. 8).

  FFT (Fast Fourier Transform) arithmetic units 102-1 to 102-n are arranged corresponding to the antenna elements 101-1 to 101-n, and the FFT arithmetic units 102-1 to 102-n are connected to the corresponding antenna elements. The input signal is divided into a plurality of (first to m-th) frequency band signals, and the divided first to m-th frequency band signals are output as first to m-th subcarrier signals, respectively. The first subcarrier signals output from the FFT operation units 102-1 to 102-n are input to the multipliers 103-1-1 to 103-n-1 and the weighting factor calculation unit 108-1, and the FFT operation unit 102 The m-th subcarrier signals output from −1 to 102-n are input to the multipliers 103-1-m to 103-nm and the weight coefficient calculation unit 108-m.

  Multipliers 103-1-1 to 103-n-1 multiply the first subcarrier signals input from FFT operation units 102-1 to 102-n by corresponding weighting factors. The weighting factor to be multiplied by each first subcarrier signal is stored in the weighting factor storage unit 107-1 in the weighting factor calculation unit 108-1. The weight coefficient storage unit 107-1 may be disposed outside the weight coefficient calculation unit 108-1.

  Similarly, multipliers 103-n-m to 103-nm multiply the m-th subcarrier signals output from FFT operation units 102-1 to 102-n by corresponding weighting factors. A weighting factor to be multiplied to each of the m-th subcarrier signals is stored in the weighting factor storage unit 107-m in the weighting factor calculation unit 108-m.

  Adder 104-1 combines the signals multiplied by the weighting coefficients output from multipliers 103-1-1 to 103-n-1, and outputs the combined signal as a first combined subcarrier signal. Similarly, adder 104-m synthesizes the signals multiplied by the weighting coefficients output from multipliers 103-1-m to 103-nm, and uses the synthesized signal as the m-th synthesized subcarrier signal. Output.

  The first to m-th combined subcarrier signals are input to demodulation section 105 and demodulated for each combined subcarrier signal. The 1st to m-th combined subcarrier signals are input to transmission path change detection sections 106-1 to 106-m arranged corresponding to the 1st to m-th combined subcarrier signals.

  The transmission path change detection units 106-1 to 106-m monitor the change of the input combined subcarrier signal and determine whether or not the change satisfies a predetermined criterion. Specifically, the transmission path change detection units 106-1 to 106-m each store the state of a reference signal (reference signal), and the state of the input composite subcarrier signal is the state of the reference signal. To monitor the change in the combined subcarrier signal. When the transmission path change detection units 106-1 to 106-m detect that the change of the combined subcarrier signal satisfies a predetermined standard, the transmission path change detection units 106-1 to 106-m A weight coefficient update signal for instructing update is output. Also, the transmission path change detection units 106-1 to 106-m update the reference signal using the combined subcarrier signal that is targeted when the change of the combined subcarrier signal satisfies a predetermined reference.

  When the weight coefficient update signals are input from the transmission path change detection units 106-1 to 106-m, the weight coefficient calculation units 108-1 to 108-m are received from the FFT calculation units 102-1 to 102-n, respectively. Using the input first to mth subcarrier signals (based on OFDM symbols received from the next time onward, the first to mth subcarriers input from each of the FFT operation units 102-1 to 102-n A new weighting factor is calculated, and the weighting factors in the weighting factor storage units 107-1 to 107-m are updated with the calculated new weighting factor.

  For example, the weighting factor calculation unit 108-1 includes the first subcarrier signals input from the FFT calculation units 102-1 to 102-n according to a known algorithm such as MSN (maximum signal to noise ratio). To be applied to each of the first subcarrier signals output from the FFT calculation units 102-1 to 102-n in the future (for example, based on the OFDM symbol received next, the FFT calculation units 102-1 to 102-102). A new weighting factor is applied (applied to each of the first subcarrier signals output from -n). Then, the weighting factor calculation unit 108-1 updates the weighting factor in the weighting factor storage unit 107-1 with the calculated new weighting factor. The weighting coefficient in the weighting coefficient storage unit 107-1 is held until it is updated next time.

  In the above, the case of multicarrier communication has been described as an example. However, the present invention is not limited to multicarrier communication as long as the communication method divides a received signal into a plurality of frequency bands.

  In the above, all the combined subcarrier signals output from the adders 104-1 to 104-m are monitored, but only a specific combined subcarrier signal may be monitored. In this case, if a change in a certain synthesized subcarrier signal satisfies a predetermined criterion, it is highly likely that a change in another synthesized subcarrier signal having a center frequency close to that synthesized subcarrier signal also satisfies the predetermined criterion. The weighting factor is also updated for a synthesized subcarrier signal that is adjacent to the certain synthesized subcarrier signal or that has a similar center frequency. As a result, the number of combined subcarrier signals to be monitored is reduced, so that the amount of calculation can be further reduced. Further, the amount of calculation can be further reduced by monitoring the combined subcarrier signal at regular time intervals or at arbitrary time intervals.

  As described above, according to the present embodiment, it is possible to turn on / off the calculation of the weighting coefficient for each subcarrier according to the change in the transmission path, thereby calculating while maintaining high quality reception characteristics. The amount can be reduced.

(Second Embodiment)
In this embodiment, an example in which a change in signal strength is monitored as a change in the combined subcarrier signal will be described.

  FIG. 2 is a diagram illustrating a first configuration example of a transmission path change detection unit in the adaptive array antenna radio reception apparatus of FIG.

  The signal strength measurement unit 202 in the transmission line change detection unit 201 (any one of 106-1 to 106-m) receives the xth composite subcarrier signal (x = 1, 2,... M). Is done. The signal strength measuring unit 202 measures the signal strength of the input x-th combined subcarrier signal and outputs the measured signal strength to the comparing unit 204.

  The comparison unit 204 calculates the difference between the signal strength of the input xth synthesized subcarrier signal and the signal strength of the reference signal. The signal strength of the reference signal is, for example, the signal strength of the x-th combined subcarrier signal that triggered the output of the previous weighting factor update signal or the signal strength of the x-th combined subcarrier signal input immediately before. The comparison unit 204 calculates the magnitude of the difference (signal strength difference) between the calculated signal strength of the x-th combined subcarrier signal and the signal strength of the reference signal as the signal strength stored in the threshold storage unit 203. Compared with the threshold value, if the magnitude of the signal strength difference is equal to or greater than the signal strength threshold value, a weight coefficient update signal is output.

  FIG. 3 is a diagram illustrating an example in which the magnitude of the difference between the signal strength of the combined subcarrier signal and the signal strength of the reference signal is equal to or greater than the signal strength threshold.

  In FIG. 3, the signal strengths of seven combined subcarrier signals S1 to S7 (the combined subcarrier signals S1 to S7 are seven consecutive combined subcarrier signals among the first to nth combined subcarrier signals); The signal strengths of the reference signals R1 to R7 corresponding to the combined subcarrier signals S1 to S7 are shown. The difference D4 between the signal strength of the combined subcarrier signal S4 and the signal strength of the reference signal R4, and the difference D5 between the signal strength of the combined subcarrier signal S5 and the signal strength of the reference signal R5 are equal to or greater than the signal strength threshold. . Accordingly, in this case, the comparison unit corresponding to the combined subcarrier signal S4 and the comparison unit corresponding to the combined subcarrier signal S5 each output a weight coefficient update signal.

  Here, the signal strength threshold value in the threshold value storage unit 203 shown in FIG. 2 may be fixed or dynamically changed by the comparison unit 204. In the latter case, the comparison unit 204, for example, based on the signal strengths of several xth synthesized subcarrier signals input in the past or the signals of several xth synthesized subcarrier signals input in the past. A new signal strength threshold is determined based on the strength and the signal strength threshold in the threshold storage unit 203.

  Further, the signal strength threshold value in the threshold value storage unit 203 may be set equal for each subcarrier (frequency band), or may be changed for each subcarrier. For example, in the case of OFDM (orthogonal frequency division multiplexing) wireless communication compliant with IEEE802.11a, pilot subcarriers play an important role. Therefore, in order to combine pilot subcarriers with high accuracy, the signal strength threshold applied to the pilot subcarrier is set low, and the signal strength threshold is set high for other subcarriers in order to reduce the amount of computation. It can happen.

  As described above, according to the present embodiment, a change in the signal strength of the subcarrier is detected, and the weighting coefficient is recalculated according to the change in the signal strength, so that the weighting coefficient can be accurately calculated with a small amount of calculation. Can be updated.

(Third embodiment)
In the present embodiment, an example will be described in which a change in phase is monitored as a change in the combined subcarrier signal.

  FIG. 4 is a diagram illustrating a second configuration example of the transmission path change detection unit in the adaptive array antenna radio reception apparatus of FIG. 1.

  The phase measurement unit 302 in the transmission path change detection unit 301 (any one of 106-1 to 106-m) receives the x-th synthesized subcarrier signal (any of x = 1, 2,... M). The The phase measurement unit 302 measures the phase of the input x-th combined subcarrier signal and outputs it to the comparison unit 204.

  The comparison unit 304 calculates the difference between the phase of the input xth composite subcarrier signal and the phase of the reference signal. The phase of the reference signal is, for example, the phase of the xth combined subcarrier signal that triggered the output of the previous weighting factor update signal, the phase of the xth combined subcarrier signal input immediately before, or the like. The comparison unit 304 compares the calculated difference between the phase of the x-th synthesized subcarrier signal and the phase of the reference signal (phase difference) with the phase threshold value stored in the threshold value storage unit 303. If the magnitude of the phase difference is greater than or equal to the phase threshold value, a weight coefficient update signal is output.

  The phase threshold value in the threshold value storage unit 303 may be fixed or may be dynamically changed by the comparison unit 304. In the latter case, the comparison unit 304, for example, based on the phase of several xth synthesized subcarrier signals input in the past or as the phase of several xth synthesized subcarrier signals input in the past. A new phase threshold value is determined based on the phase threshold value in the threshold value storage unit 303.

  Further, the phase threshold value in the threshold value storage unit 303 may be set equal for each subcarrier or may be changed for each subcarrier. For example, in the case of OFDM (orthogonal frequency division multiplexing) wireless communication compliant with IEEE802.11a, pilot subcarriers play an important role. Therefore, in order to accurately combine the pilot subcarriers, the phase threshold applied to the pilot subcarrier can be set low, and the phase threshold can be set high for other subcarriers in order to reduce the amount of calculation. possible.

  As described above, according to the present embodiment, the weighting coefficient can be updated with high accuracy and with a small amount of calculation by detecting the phase change of the subcarrier and recalculating the weighting coefficient according to the phase change. .

(Fourth embodiment)
In the present embodiment, an example will be described in which a change in signal strength and a change in phase are monitored as changes in the combined subcarrier signal.

  FIG. 5 is a diagram illustrating a third configuration example of the transmission path change detection unit in the adaptive array antenna radio reception apparatus of FIG. 1.

  The signal intensity and phase measurement unit 402 in the transmission path change detection unit 401 (any one of 106-1 to 106-m) has an x-th synthesized subcarrier signal (any of x = 1, 2,... M). Is entered. The signal strength and phase measurement unit 402 measures the signal strength and phase of the input xth composite subcarrier signal and outputs the measured signal strength and phase to the comparison unit 404.

  The comparison unit 404 calculates the difference between the signal strength and phase of the input xth synthesized subcarrier signal and the signal strength and phase of the reference signal. The signal strength and phase of the reference signal are, for example, the signal strength and phase of the xth composite subcarrier signal that triggered the output of the previous weighting factor update signal, or the signal strength of the xth composite subcarrier signal input immediately before And phase. The comparison unit 404 uses the signal strength threshold stored in the threshold storage unit 403 to calculate the magnitude of the difference between the calculated signal strength and phase of the x-th combined subcarrier signal and the signal strength and phase of the reference signal. Compared with the value and the phase threshold value, and when the magnitudes of these differences are both equal to or larger than the threshold value, a weight coefficient update signal is output.

  The signal intensity threshold value and the phase threshold value in the threshold value storage unit 403 may be fixed or dynamically changed by the comparison unit 404. In the latter case, the comparison unit 404, for example, based on the signal strength and phase of several xth synthesized subcarrier signals input in the past, or some xth synthesized subcarrier signals input in the past. A new threshold is determined based on the signal intensity and phase of the signal and the signal intensity threshold and phase threshold in the threshold storage unit 403.

  Further, the signal strength threshold value and the phase threshold value in the threshold value storage unit 403 may be set equal for each subcarrier (frequency band) or may be changed for each subcarrier (frequency band). For example, in the case of OFDM (orthogonal frequency division multiplexing) wireless communication compliant with IEEE802.11a, pilot subcarriers play an important role. Therefore, in order to synthesize pilot subcarriers with high accuracy, the signal strength threshold value and phase threshold value applied to the pilot subcarriers are set low, and these thresholds are set for other subcarriers in order to reduce the amount of calculation. It is possible to set the value high.

  As described above, according to the present embodiment, the signal strength change and the phase change of the subcarrier are detected, and the weighting coefficient is recalculated according to the signal strength change and the phase change. The weighting factor can be updated with the quantity.

(Fifth embodiment)
FIG. 6 shows a configuration example of an adaptive array antenna radio receiving apparatus according to the present embodiment.

  This adaptive array antenna radio receiving apparatus is obtained by adding a fixed time measurement unit 501 to the adaptive array antenna radio receiving apparatus of FIG. The other parts are the same as in FIG. 1, and the same parts as those shown in FIG.

  The fixed time measuring unit 501 in FIG. 6 measures the time from when the weighting factor calculating units 108-1 to 108-m last updated the weighting factor to the present, and a fixed time (first set time) has elapsed. At the time, an update instruction signal is output to the corresponding weight coefficient calculation units 108-1 to 108-m. Alternatively, the fixed time measurement unit 501 always outputs an update instruction signal every time the fixed time (second set time) elapses regardless of the time when the weighting coefficient is updated last time.

  The weighting factor calculation units 108-1 to 108-m that have received the update instruction signal calculate the weighting factor in the same manner as in the first embodiment, and the weighting factor in the weighting factor calculation units 108-1 to 108-m. The weighting factors stored in the storage units 107-1 to 107-m are updated with the calculated weighting factors.

  The first setting time or the second setting time may be set equal for each subcarrier (frequency band), or may be changed for each subcarrier (frequency band). For example, in the case of OFDM (orthogonal frequency division multiplexing) wireless communication compliant with IEEE802.11a, pilot subcarriers play an important role. Therefore, in order to combine the pilot subcarriers with high accuracy, the first setting time or the second setting time applied to the pilot subcarriers is set short, and the other subcarriers are used to reduce the calculation amount. It is possible to set the first or second set time longer.

  In addition, when the packet error rate and the bit error rate are low in the demodulator 105, the set time may be adaptively changed, for example, by increasing the first set time or the second set time in order to reduce the amount of calculation. .

  As described above, according to the present embodiment, since the weighting coefficient is updated at least every certain time, it is possible to prevent the weighting coefficient from being updated due to some problem.

(Sixth embodiment)
FIG. 7 shows a configuration example of an adaptive array antenna radio receiving apparatus according to the present embodiment.

  Transmission path change detection sections 701-1 to 701-m detect changes in the first to m-th combined subcarrier signals and output the detected change amounts.

  Maximum change subcarrier detection units 702-1 to 702-L are respectively assigned to some specific transmission line change detection units, and receive the change amounts output from the corresponding transmission line change detection units. For example, the maximum change subcarrier detection unit 702-1 is assigned to x transmission path change detection units 701-1 to 701-x (assigned to the first to xth combined subcarrier signals). The amount of change output from these transmission line change detectors 701-1 to 701-x is received.

  Maximum change subcarrier detectors 702-1 to 702-L specify the largest change amount among the received change amounts, and update the weighting coefficient for the subcarrier (frequency band) having the specified change amount. Update on signal is output, and an update off signal is output for other subcarriers (frequency bands).

  For example, the maximum change subcarrier detection unit 702-1 has the largest change amount input from the transmission line change detection units 701-1 to 701-x, when the one from the transmission line change detection unit 701-1 is the largest. An update-on signal is output for the input from the transmission line change detection unit 701-1 (for the first frequency band), and the input from the other transmission line change detection units 701-2 to 701-x. The update off signal is output (for the second to xth frequency bands).

  Weight coefficient calculation units 703-1 to 703-L are arranged corresponding to maximum change subcarrier detection units 702-1 to 702-L. A switch is disposed between each of the weight coefficient calculation units 703-1 to 703-L and the FFT operation units 102-1 to 102-n. For example, x switches 704-1 to 704-x are arranged in the weight coefficient calculation unit 703-1. The switch 704-1 turns on / off the input of the first subcarrier signal output from the FFT calculation units 102-1 to 102-n to the weighting factor calculation unit 703, and the switch 704-x includes an FFT calculation unit. The input to the weighting coefficient calculation unit 703 of the x-th subcarrier signal output from 102-1 to 102-n is turned on / off.

  The update on signal and the update off signal output from the maximum change subcarrier detection units 702-1 to 702-L are respectively input to the corresponding switches. For example, the update on signal or the update off signal related to the first frequency band output from the maximum change subcarrier detection unit 702-1 is input to the switch 704-1. When the update ON signal is input, the switch 704-1 inputs the first subcarrier signal output from the FFT calculation units 102-1 to 102-n to the weighting coefficient calculation unit 703-1, and updates OFF. When a signal is input, input of the first subcarrier signal output from the FFT calculation units 102-1 to 102-n to the weighting coefficient calculation unit 703-1 is blocked.

  When the subcarrier signal is input from the FFT operation units 102-1 to 102-n, the weighting factor calculation units 703-1 to 703-L calculate the weighting factor using the input subcarrier signal and calculate The weighting factor in the weighting factor storage units 705-1 to 705-L is updated with the weighting factor thus obtained. For example, when the first subcarrier signal is input from the FFT operation units 102-1 to 102-n, the weighting factor calculation unit 703-1 calculates and calculates the weighting factor using the first subcarrier signal. The weighting factor in the weighting factor storage unit 705-1 is updated with the weighting factor.

  In the above, the maximum change subcarrier detection units 702-1 to 702-L identify the maximum change amount every time the change amount is input, and send an update on signal for the combined subcarrier signal having the maximum change amount. The update ON signal may be output only when the maximum change amount exceeds a certain threshold value.

  In the above description, the weighting coefficient is updated only for the combined subcarrier signal having the largest change amount. However, for another combined subcarrier signal adjacent to the combined subcarrier signal or close to the center frequency, The weighting factor may be updated with the same value as the updated weighting factor.

  As described above, according to the present embodiment, the calculation amount can be reduced because the weighting coefficient is updated for subcarriers having a large transmission path change.

(Seventh embodiment)
FIG. 8 shows a configuration example of an adaptive array antenna radio receiving apparatus according to the present embodiment.

  Between the antenna elements 101-1 to 101-n and the FFT operation units 102-1 to 102-n, the radio signals received by the antenna elements 101-1 to 101-n are converted into electrical analog signals. Radio units 801-1 to 801-n and AD converters 802-1 to 802-n that convert analog signals generated by the radio units 801-1 to 801-n into digital signals are arranged. In addition, an on / off control unit 803 that performs on / off control of operations of the radio units 801-1 to 801-n and the AD converters 802-1 to 802-n is provided. Since the configuration of the other parts is the same as that of FIG. 1, the same reference numerals are given to the same parts as in FIG. 1, and the detailed description is omitted.

  When the weight count calculation units 108-1 to 108-m calculate new weighting coefficients based on the update instruction signals from the transmission path change detection units 106-1 to 106-m, the calculated new weighting coefficients are turned on / off. Output to the off control unit 803. The on / off control unit 803 determines whether there is an antenna element with relatively small received power based on the input new weighting factor. For example, when there is a weighting factor whose difference from the average of the input weighting factors is smaller than a predetermined threshold, the antenna element corresponding to the weighting factor determines that the received power is small, and the radio unit corresponding to the antenna element And the operation of the AD converter is turned off. When the operation is turned off, the on / off control unit 803 notifies the FFT operation unit, multiplier, adder, and the like corresponding to the wireless unit and AD converter that are turned off.

  As described above, when there is an antenna element with low reception power, power consumption can be reduced by stopping reception processing from the antenna element.

It is a block diagram which shows the structural example of the adaptive array antenna radio | wireless receiver according to the 1st Embodiment of this invention. It is a block diagram which shows the 1st structural example of a path | route change detection part. It is a figure which shows the example from which the magnitude | size of the difference of the signal strength of a synthetic | combination subcarrier signal and the signal strength of a reference signal becomes more than a signal strength threshold value It is a block diagram which shows the 2nd structural example of a path | route change detection part. It is a block diagram which shows the 3rd structural example of a path | route change detection part. It is a block diagram which shows the structural example of the adaptive array antenna radio | wireless receiver according to the 5th Embodiment of this invention. It is a block diagram which shows the structural example of the adaptive array antenna radio | wireless receiver according to the 6th Embodiment of this invention. It is a block diagram which shows the structural example of the adaptive array antenna radio | wireless receiver according to the 7th Embodiment of this invention.

Explanation of symbols

101-1 to 101-n Antenna elements 102-1 to 102-n FFT operation units 103-1-1 to 103-nm multipliers 104-1 to 104-m adder 105 demodulation units 106-1 to 106- m, 201, 301, 401, 701-1 to 701-m Transmission path change detection units 107-1 to 107-m, 705-1 to 705-L Weight coefficient storage units 108-1 to 108-m, 703-1 703-L Weight coefficient calculation unit 202 Signal strength measurement unit 203, 303, 403 Threshold storage unit 204, 304, 404 Comparison unit 302 Phase measurement unit 402 Signal strength and phase measurement unit 501 Constant time measurement unit 702-1 702-L Maximum change subcarrier detection unit 801-1 to 801-n Radio unit 802-1 to 802-n ADC
803 On / off control unit

Claims (6)

A plurality of receiving units each including an antenna element;
A plurality of FFT (Fast Fourier Transform) arithmetic units that are arranged corresponding to the plurality of receiving units and that divide and output the received signals received by the corresponding receiving units into signals of a plurality of frequency bands by Fourier transform;
A weighting factor storage unit that stores a weighting factor corresponding to each of the plurality of frequency bands for each FFT calculation unit;
The same frequency band multiplied by the weighting coefficient obtained by multiplying the weighting coefficient corresponding to the signal of the same frequency band output from each of the plurality of FFT operation parts by multiplying it from the weighting coefficient storage unit Weighting synthesis means for synthesizing the signals of
A transmission line change monitoring unit that monitors a change in the combined signal generated by the weighting combining unit, and determines whether the change in the combined signal satisfies a predetermined weight coefficient update criterion;
When the change of the combined signal satisfies the predetermined weight coefficient update criterion, the same frequency band signal output from the plurality of FFT calculation units is used to set the same frequency for each FFT calculation unit. A weighting factor calculating unit that calculates a corresponding weighting factor and stores the calculated weighting factor in the weighting factor storage unit;
A wireless receiving device. The transmission path change monitoring means is
A signal intensity calculating means for calculating the signal intensity of the combined signal, using the combined signal as an input;
The radio reception apparatus according to claim 1, wherein a difference between a signal strength of the synthesized signal and a signal strength of the synthesized signal input in the past is monitored as a change in the synthesized signal. The transmission path change monitoring means is
Phase calculation means for calculating the phase of the combined signal, using the combined signal as an input;
The radio reception apparatus according to claim 1, wherein a difference between a phase of the synthesized signal and a phase of the synthesized signal input in the past is monitored as a change in the synthesized signal. The transmission path change monitoring means is
A signal intensity phase calculating means for calculating a signal intensity and a phase of the synthesized signal with the synthesized signal as an input;
The radio reception apparatus according to claim 1, wherein a difference between a signal strength and a phase of the composite signal and a signal strength and a phase of the composite signal input in the past is monitored as a change in the composite signal.   5. The weighting factor calculation unit calculates the weighting factor when a change in the combined signal does not satisfy the predetermined weighting factor update criterion for a predetermined time. 5. The wireless receiving device according to claim 1.   When the weighting factor is calculated by the weighting factor calculating means, it is determined whether or not there is a weighting factor that does not satisfy a predetermined weighting factor criterion in the calculated weighting factor. The radio reception apparatus according to claim 1, further comprising an on / off control unit that stops the operation of the reception unit related to the weighting coefficient.

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