JP2020141289A - Wireless device - Google Patents

Abstract

To improve the reception performance with a simple configuration.SOLUTION: A wireless device includes a plurality of branches that perform signal processing on respective received signals, a correlation calculation unit that calculates an autocorrelation value of the processing signal of each of the branches and a cross-correlation value between the processing signals of the respective branches from the processing signal of the branches. A reference branch determination unit that determines a branch having the maximum autocorrelation value from the plurality of branches as a reference branch, a coefficient output unit that outputs a weight coefficient without phase compensation of the processing signal of the reference branch on the basis of the cross-correlation value, a weighting processing unit that weights the processing signal of each of the branches using the weight coefficient output by the coefficient output unit, and a synthesis unit that synthesizes the processing signals of the respective branches weighted by the weighting processing unit.SELECTED DRAWING: Figure 4

Description

The present invention relates to a wireless device.

In recent years, wireless communication has become widespread. Diversity reception is known as a technology related to wireless communication. Diversity reception is a technique performed by a receiving device having a plurality of antennas, and is a selective diversity method in which a branch signal obtained by one of the antennas is preferentially used, or each obtained by each of the plurality of antennas. The signal-to-noise ratio can be improved by a maximum ratio synthesis diversity method for synthesizing branch signals.

Such diversity reception is disclosed in, for example, the following Patent Documents 1 to 3. Specifically, Patent Document 1 discloses a technique for synthesizing each branch signal with appropriate weighting in diversity reception. Patent Document 2 discloses a technique for improving reception quality, operation certainty, and the like in diversity reception. Patent Document 3 discloses a technique for appropriately selecting a selective diversity method and a maximum ratio synthetic diversity method.

Japanese Unexamined Patent Publication No. 2012-44399 Japanese Unexamined Patent Publication No. 2008-42728 JP-A-2007-189316

However, the technique described in Patent Document 1 has complicated functions for autocorrelation peak detection, peak interval determination, and the like, and the circuit scale becomes bloated. Further, in the technique described in Patent Document 1, although the gain of the branch signal is adjusted, the phase component is not considered. Therefore, it has been difficult to improve the reception performance with a simple circuit configuration by the technique described in Patent Document 1 and also by the technique described in other patent documents.

Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to provide a new and improved wireless device capable of improving reception performance with a simple configuration. There is.

In order to solve the above problem, according to a certain viewpoint of the present invention, a plurality of branches that perform signal processing on the received signals corresponding to each, and autocorrelation of the processed signals of each branch from the processed signals of each branch. The correlation calculation unit that calculates the value and the cross-correlation value between the processed signals of each branch, the reference branch determination unit that determines the branch having the maximum autocorrelation value from the plurality of branches as the reference branch, and the cross-correlation. Based on the value, the processing signal of each branch is weighted by using the coefficient output unit that outputs the weight coefficient without phase compensation of the processing signal of the reference branch and the weight coefficient output by the coefficient output unit. Provided is a wireless device including a weighting processing unit and a synthesis unit that synthesizes processing signals of the respective branches weighted by the weighting processing unit.

The coefficient output unit includes a plurality of weight coefficient calculation units and an output switch located between the plurality of weight coefficient calculation units and the weighting processing unit, and is included in the plurality of weight coefficient calculation units. Each weight coefficient calculation unit calculates the weight coefficient with the phase compensation of the processing signal of the other branch without the phase compensation of the processing signal of any branch, and the output switch is determined as the reference branch. The weighting coefficient calculation unit for calculating the weighting coefficient without phase compensation of the branch processing signal may be connected to the weighting processing unit.

The coefficient output unit further has an input switch located between the correlation calculation unit and the plurality of weight coefficient calculation units, and the input switch is the correlation calculation unit and a branch determined as the reference branch. A weight coefficient calculation unit that calculates a weight coefficient without phase compensation of the processed signal may be connected.

The weight coefficient calculation unit has one eigenvector of a correlation matrix having an autocorrelation value of the processed signal of each branch as a diagonal component and a cross-correlation value between the processed signals of each branch as an off-diagonal component. It may be calculated as a weight coefficient.

Each branch may include an antenna, a filter, an AD converter and a mixer.

The processed signal of the branch may be a signal obtained by subjecting the received signal received by the antenna to signal processing including filtering, AD conversion, and down conversion.

According to the present invention described above, it is possible to improve the reception performance with a simple configuration.

It is explanatory drawing which shows the structure of the wireless communication system for disaster prevention radio by embodiment of this invention. It is explanatory drawing which shows the comparative example of diversity reception. It is explanatory drawing which shows the structure of the receiver 30 by embodiment of this invention. It is explanatory drawing which shows the structure of the maximum ratio synthesis part 370. It is explanatory drawing which shows the specific example of the weighting performed by the weighting processing unit 376. It is a flowchart which shows the operation of the maximum ratio synthesis part 370.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the present specification and the drawings, components having substantially the same functional configuration are designated by the same reference numerals, so that duplicate description will be omitted.

Further, in the present specification and drawings, a plurality of components having substantially the same functional configuration may be distinguished by adding different alphabets after the same reference numerals. For example, a plurality of configurations having substantially the same functional configuration or logical significance are distinguished as necessary, such as receiver 30A and receiver 30B. However, when it is not necessary to particularly distinguish each of the plurality of components having substantially the same functional configuration, only the same reference numerals are given to each of the plurality of components. For example, when it is not necessary to distinguish between the receiver 30A and the receiver 30B, each receiver is simply referred to as a receiver 30.

<1. Overview of wireless communication system>
An embodiment of the present invention relates to a wireless device that performs diversity reception. The wireless device is applied to, for example, a wireless communication system for disaster prevention radio. A wireless communication system for disaster prevention radio is a system for reporting emergency broadcasts or warnings regarding disasters such as earthquakes, tsunamis, typhoons or heavy rains. An outline of a wireless communication system for such disaster prevention radio will be described with reference to FIG.

FIG. 1 is an explanatory diagram showing a configuration of a wireless communication system for disaster prevention radio according to an embodiment of the present invention. As shown in FIG. 1, the wireless communication system for disaster prevention radio according to the embodiment of the present invention includes an operation console 10, a master station radio 20, a receiver 30, and a relay station radio 40. ..

The console 10 is a device for inputting voice and inputting operation settings of the receiver 30 by the operator when making a report by a wireless communication system. More specifically, the operator uses the console 10 to input the content of the report, the target of the report, the operation setting at the time of the report, and the like. The console 10 transmits the input information to the master station radio 20 via the wired network.

The master station radio 20 transmits a radio signal indicating information input from the console 10 to the receiver 30 and the relay station radio 40.

The receiver 30 is a wireless device having a ringing function, and is installed in, for example, a house, a hospital, a public facility, or the like. The receiver 30 receives the radio signal transmitted by the master station radio 20 and makes a report based on the radio signal. More specifically, the receiver 30 determines whether or not the own station is included in the target of the report, and if the own station is included in the target, the receiver 30 reflects the operation setting included in the wireless signal. , Make a report using the built-in speaker. Further, the receiver 30 has a plurality of antennas as shown in FIG. The receiver 30 can perform diversity reception, which will be described later, by utilizing a plurality of antennas.

The relay station radio 40 is a radio device that relays a radio signal transmitted by the master station radio 20. More specifically, the relay station radio 40 converts the radio signal transmitted by the master station radio 20 into a radio signal having a frequency different from the frequency of the radio signal, and receives the converted radio signal. It is transmitted to the machine 30. As a result, it is possible to make a report even in an area where the radio signal transmitted from the master station radio 20 does not reach. In the example shown in FIG. 1, even if the radio signal transmitted from the master station radio 20 does not reach the receiver 30B, the receiver 30B receives the radio signal from the relay station radio 40 and makes a report. Is possible. The relay station radio 40 also has a plurality of antennas like the receiver 30, and by utilizing the plurality of antennas, it is possible to execute diversity reception described later.

<2. Background ＞
Embodiments of the present invention relate to the above-mentioned wireless communication system, in particular, diversity reception that can be executed by the receiver 30 and the relay station radio 40 and the like. In order to further clarify the superiority of diversity reception according to the embodiment of the present invention, a comparative example of diversity reception will be described prior to the description of diversity reception according to the embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a comparative example of diversity reception. Specifically, FIG. 2 shows the time-series changes in the autocorrelation of the two branch signals. In the autocorrelation of the branch signal 1, peaks appear at 1 symbol length intervals. In the autocorrelation of the planch signal 2, there is an error between the peak interval and one symbol length. Since it is desirable that the peak interval is ideally one symbol length, it can be said that the signal quality of the branch signal 1 is higher than the signal quality of the branch signal 2 in the example shown in FIG.

Therefore, in the comparative example of diversity reception, the autocorrelation of each branch signal is calculated, the peak of the autocorrelation is detected, the peak interval of the autocorrelation is specified, and the difference length between the peak interval and one symbol length is calculated. A circuit is used for determining the magnitude relationship of the difference length of each branch signal and setting the gain of each branch signal according to the determination result. For example, in the comparative example of diversity reception, the gain of the branch signal having a small difference length is set high, and the gain of the branch signal having a large difference length is set low. The multiplier weights each branch signal according to the gain setting, and the maximum ratio synthesizer adds the weighted branch signal and outputs the composite signal. The branch signal is, for example, a received signal obtained by removing the guard period and weighting (gain, phase compensation) by a weight coefficient based on the channel estimation result from the FFT output.

However, in the above-mentioned comparative example of diversity reception, the functions for autocorrelation peak detection, peak interval determination, and the like are complicated, and the circuit scale becomes bloated. In addition, the gain is adjusted by comparing the difference length between the peak interval of the autocorrelation and the ideal symbol length with the reference value, so the reference value or gain adjustment amount is optimized according to the actual device performance and communication system. It is complicated to set. Further, in the comparative example of diversity reception, although the gain of each branch signal is adjusted based on the signal quality of each branch signal, the adjustment of the phase component based on the signal quality of each branch signal is not considered.

The inventor of the present invention has come to create a technique according to an embodiment of the present invention with the above circumstances as the first point of view. According to the embodiment of the present invention, it is possible to improve the reception performance with a simple configuration. Hereinafter, the configuration of the receiver 30 to which the technique according to the embodiment of the present invention is implemented will be described. Since the configuration of the receiver 30 described below can be similarly applied to the configuration for reception of the relay station radio 40, detailed description of the configuration of the relay station radio 40 will be omitted.

<3. Receiver configuration>
FIG. 3 is an explanatory diagram showing the configuration of the receiver 30 according to the embodiment of the present invention. As shown in FIG. 3, the receiver 30 according to the embodiment of the present invention has two antennas 32, an analog unit 34, and a digital unit 36.

(antenna)
The antenna 32 receives the radio signal transmitted from the master station radio 20 or the relay station radio 40, and outputs a high-frequency reception signal to the analog unit 34. One antenna 32 of the two antennas 32 constitutes branch 1, and the other antenna 32 constitutes branch 2. Although FIG. 3 shows an example in which the number of branches is two, the number of branches is not limited to two and may be three or more.

(Analog part)
The analog unit 34 is configured to process a signal in the analog region. Specifically, the analog unit 34 has BPF 342, LNA 344, mixer 346, and ADC 348 that form branch 1, and BPF 342, LNA 344, mixer 346, and ADC 348 that form branch 2.

The BPF (Band-Pass Filter) 342 passes a predetermined frequency band of the high frequency signal input from the antenna 32. The LNA (Low Noise Amplifier) 344 amplifies the signal input from the BPF 342. The mixer 346 down-converts the signal input from the LNA 344. The ADC (Analog-to-digital converter) 348 samples the analog format signal input from the mixer 346 and outputs the digital format signal.

(Digital section)
The digital unit 36 is configured to process a signal in the digital domain. Specifically, the digital unit 36 includes the BPF 362, the mixer 364, the RRC filter 366, the Hilbert filter 368, and the mixer 369 that form the branch 1, and the BPF 362, the mixer 364, the RRC 366, and the Hilbert filter 368 that form the branch 2. It has a mixer 369 and. Further, the digital unit 36 has a maximum ratio synthesis unit 370, a delay detection unit 390, and a demodulation unit 392.

The BPF 362 passes a predetermined frequency band of the signal input from the ADC 348. The mixer 364 shifts the frequency band of the signal input from the BPF 362. The RRC (root-raised cosine) filter 366 filters the signal input from the mixer 364 to satisfy the Nyquist condition. The Hilbert filter 368 converts the signal input from the RRC filter 366 into Hilbert. The mixer 369 orthogonally modulates the signal input from the Hilbert filter 368. In the following, the baseband signal output from the mixer 369 constituting the branch 1 is referred to as a branch signal 1 or a processing signal of the branch 1, and the baseband signal output from the mixer 369 constituting the branch 2 is referred to as a branch signal 2 or a branch. It may be referred to as a processing signal of 2.

A branch signal 1 and a branch signal 2 are input to the maximum ratio synthesis unit 370. The maximum ratio synthesizing unit weights each of the input branch signal 1 and branch signal 2 using a weighting coefficient, and synthesizes and outputs the weighted branch signal 1 and branch signal 2. The delay detection unit 390 performs delayed detection of the composite signal input from the maximum ratio synthesis unit 370, and the demodulation unit 392 uses, for example, a π / 4DQPSK (Differential Quadrature Phase Shift Keying) method for the signal input from the delay detection unit 390. Demodulate with.

<4. Configuration of maximum ratio synthesizer>
Here, a more specific configuration of the maximum ratio synthesis unit 370 will be described with reference to FIG.

FIG. 4 is an explanatory diagram showing the configuration of the maximum ratio synthesis unit 370. As shown in FIG. 4, the maximum ratio synthesis unit 370 includes a correlation calculation unit 372, a reference branch determination unit 373, a weight coefficient calculation unit 374, a weighting processing unit 376, a composition unit 378, and an input switch S1. , And an output switch S2. Each function such as the correlation calculation unit 372, the reference branch determination unit 373, the weight coefficient calculation unit 374, the weighting processing unit 376, and the synthesis unit 378 may be realized by the cooperation of hardware and software. For example, each function can be realized by the processor running software in memory.

(Correlation calculation unit)
The correlation calculation unit 372 performs a correlation calculation on each branch signal to obtain a correlation matrix. The correlation matrix has an autocorrelation value of each branch signal as a diagonal component and a cross-correlation value between each branch signal as an off-diagonal component. For example, the correlation calculation unit 372 performs a correlation calculation on the branch signal 1 (x ₁ [k]) and the branch signal 2 (x ₂ [k]), and obtains the correlation matrix Rxx shown in the following equation 1.

In Equation 1, K is the number of samples of data used in the calculation, and the subscript * indicates the complex conjugate. Further, the value a in Equation 1 indicates the autocorrelation value of the branch signal 1, the value c indicates the autocorrelation value of the branch signal 2, and the values b and b * represent the cross-correlation values of the branch signal 1 and the branch signal 2. Shown. The correlation calculation unit 372 outputs the value a and the value c to the reference branch determination unit 373, and outputs the correlation matrix shown in the equation 1 to the input switch S1.

(Reference branch judgment unit)
The reference branch determination unit 373 determines from a plurality of branches the branch having the maximum autocorrelation value of the branch signal as the reference branch. For example, when the value a, which is the autocorrelation value of the branch signal 1, is higher than the value c, which is the autocorrelation value of the branch signal 2, the reference branch determination unit 373 determines branch 1 as the reference branch. Then, the reference branch determination unit 373 outputs the determination result of the reference branch to the input switch S1 and the output switch S2. Since the height of the autocorrelation value of the branch signal depends on the quality of the branch signal, the reference branch having the maximum autocorrelation value is considered to be the branch having the highest reception quality.

(Weight coefficient calculation unit)
The weight coefficient calculation unit 374 calculates the weight coefficient for all branches without phase compensation of the processing signal of any branch by using the correlation matrix input from the correlation calculation unit 372 via the input switch S1. .. For example, the weight coefficient calculation unit 374 # 1 calculates the weight coefficient W ₁ with the phase compensation of the branch signal 2 without the phase compensation of the branch signal 1. The weight coefficient calculation unit 374 # 2 calculates the weight coefficient W ₂ with the phase compensation of the branch signal 1 and without the phase compensation of the branch signal 2. Here, an example in which the number of branches is two is shown, but if the number of branches is N, the weight coefficient calculation unit 374 # 1 for calculating the weight coefficient at which the phase compensation component of the branch signal 1 becomes 0. , Weight coefficient calculation unit 374 # 2, which calculates the weight coefficient at which the phase compensation component of the branch signal 2 becomes 0, ..., Weight for calculating the weight coefficient at which the phase compensation component of the branch signal (N-1) becomes 0. The coefficient calculation unit 374 # (N-1) and the weight coefficient calculation unit 374 # N for calculating the weight coefficient at which the phase compensation component of the branch signal N becomes 0 are provided.

Here, the input switch S1 is located between the correlation calculation unit 372 and the plurality of weight coefficient calculation units 374. The input switch S1 has a correlation calculation unit 372 and a weight coefficient calculation unit 374 that calculates a weight coefficient without phase compensation of the branch signal of the reference branch based on the determination result of the reference branch input from the reference branch determination unit 373. And connect. For example, when the reference branch is branch 1, the input switch S1 connects the correlation calculation unit 372 and the weight coefficient calculation unit 374 # 1. On the other hand, when the reference branch is branch 2, the input switch S1 connects the correlation calculation unit 372 and the weight coefficient calculation unit 374 # 2.

Further, the output switch S2 is located between the plurality of weight coefficient calculation units 374 and the weighting processing unit 376. The output switch S2 includes a weight coefficient calculation unit 374 and a weight processing unit 376 that calculate a weight coefficient without phase compensation of the branch signal of the reference branch based on the determination result of the reference branch input from the reference branch determination unit 373. To connect. For example, when the reference branch is branch 1, the output switch S2 connects the weight coefficient calculation unit 374 # 1 and the weight processing unit 376. On the other hand, when the reference branch is branch 2, the output switch S2 connects the weight coefficient calculation unit 374 # 2 and the weight processing unit 376.

Therefore, when the reference branch is a branch 1, the correlation matrix obtained by the correlation calculation unit 372 is input to the weight coefficient calculating section 374 # 1, the weight coefficient calculating section 374 # 1 calculates the weight coefficients W _1, The output switch S2 outputs the weight coefficient W ₁ to the weighting processing unit 376. On the other hand, when the reference branch is branch 2, the correlation matrix obtained by the correlation calculation unit 372 is input to the weight coefficient calculation unit 374 # 2, and the weight coefficient calculation unit 374 # 2 calculates the weight coefficient W ₂ and outputs it. The switch S2 outputs the weight coefficient W ₂ to the weight processing unit 376.

That is, the weight coefficient calculation unit 374, together with the input switch S1 and the output switch S2, outputs the weight coefficient W with phase compensation of the processing signals of the other branches of the reference branch and without phase compensation of the processing signals of the reference branch. Functions as a coefficient output unit.

The method of calculating the weight coefficient W by each weight coefficient calculation unit 374 is not particularly limited. For example, each weight coefficient calculation unit 374 may calculate one eigenvector of the correlation matrix as the weight coefficient W. Hereinafter, the eigenvalue of the correlation matrix is shown in Equation 2, the maximum eigenvalue is shown in Equation 3, and a specific example of the eigenvector corresponding to the maximum eigenvalue is shown in Equation 4.

(Weighting processing unit)
Each branch signal is input to the weighting processing unit 376. Further, any weight coefficient W is input to the weighting processing unit 376 via the output switch S2. The weighting processing unit 376 weights each branch signal using the weighting coefficient W input via the output switch S2. Then, the weighting processing unit 376 outputs each weighted branch signal to the synthesis unit 378.

Here, "λ _1- c" and "λ _1- a" shown in Equation 4 are real numbers, and "b" and "b ^* " are basically complex numbers. Therefore, when the reference branch is branch 1 and the weight coefficient W ₁ is input to the weighting processing unit 376, the branch signal 1 is weighted with gain correction but not phase compensation. On the other hand, the branch signal 2 is weighted with gain correction and phase compensation so that the branch signal 1 is in phase.

On the contrary, when the reference branch is branch 2 and the weight coefficient W ₂ is input to the weight processing unit 376, the branch signal 1 is accompanied by gain correction and the phase compensation is such that the branch signal 2 is in phase. Weighting is performed with. On the other hand, the branch signal 2 is weighted with gain correction but not phase compensation.

A specific example of weighting performed by such a weighting processing unit 376 will be described with reference to FIG.

FIG. 5 is an explanatory diagram showing a specific example of weighting performed by the weighting processing unit 376. FIG. 5 shows a signal point p1 in the IQ plane of the branch signal 1 and a signal point p2 in the IQ plane of the branch signal 2. If branch 1 is a reference branch, by a weighting with weighting coefficients W _1, the signal point p2 of the branch signal 2 is rotated by an angle d, the phase of the branch signal 2 is oriented in the phase branch signal 1.

(Synthesis part)
The synthesis unit 378 adds (synthesizes) each of the weighted branch signals input from the weighting processing unit 376, and outputs the composite signal.

<5. Operation of maximum ratio synthesizer>
The configuration of the maximum ratio synthesis unit 370 has been described above. The operation of the maximum ratio synthesizing unit 370 will be summarized below with reference to FIG.

FIG. 6 is a flowchart showing the operation of the maximum ratio synthesis unit 370. As shown in FIG. 6, first, the correlation calculation unit 372 calculates the correlation matrix of each branch signal (S410). Then, the reference branch determination unit 373 determines from the plurality of branches the branch having the maximum autocorrelation value of the branch signal as the reference branch (S420).

After that, the input switch S1 connects the weight coefficient calculation unit 374 for calculating the weight coefficient without phase compensation of the branch signal of the reference branch and the correlation calculation unit 372, and the output switch S2 connects the phase of the branch signal of the reference branch. The weight coefficient calculation unit 374 for calculating the weight coefficient without compensation and the weighting processing unit 376 are connected (S430).

Then, the weight coefficient calculation unit 374 connected by the input switch S1 and the output switch S2 calculates the weight coefficient (S440). Next, the weighting processing unit 376 weights each branch signal using the weight coefficient W input via the output switch S2 (S450), and the synthesis unit 378 weights each branch signal by the weighting processing unit 376. Is synthesized and a synthesized signal is output (S460).

<6. Action effect>
As described above, according to the embodiment of the present invention, it is assumed that there is a branch having a low reception quality (reception gain) by aligning the phase of another branch signal with the branch signal of the reference branch having the highest reception quality. However, it is possible to suppress deterioration of demodulation accuracy.

Further, since the autocorrelation value used for determining the reference antenna is a parameter calculated in the method of calculating the weight coefficient by eigenvalue decomposition, the calculation of the autocorrelation value does not add a function. Since the weight coefficient can be switched by switching the weight coefficient calculation unit (calculation formula), it does not correspond to a new implementation of a block having a high calculation load. Therefore, in the embodiment of the present invention, it is possible to improve the reception performance while suppressing the enlargement of the circuit scale. In the technique according to the embodiment of the present invention, since the theoretical performance of the maximum ratio synthesis is maintained, there is an advantage that a certain performance can be exhibited without any special adjustment.

Although preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, the present invention is not limited to such examples. It is clear that a person having ordinary knowledge in the field of technology to which the present invention belongs can come up with various modifications or modifications within the scope of the technical ideas described in the claims. , These are also naturally understood to belong to the technical scope of the present invention.

For example, each step in the processing of the receiver 30 of the present specification does not necessarily have to be processed in chronological order in the order described as a flowchart. For example, each step in the processing of the receiver 30 may be processed in an order different from the order described in the flowchart, or may be processed in parallel.

Further, although the example in which the wireless communication system according to the embodiment of the present invention is applied to the disaster prevention radio has been described above, the application destination of the wireless communication system according to the embodiment of the present invention is not limited to the disaster prevention radio. For example, the wireless communication system according to the embodiment of the present invention may be applied to other communication such as cellular communication or wireless LAN.

10 Operation console 20 Master station radio 30 Receiver 32 Antenna 34 Analog section 36 Digital section 40 Relay station radio 342 BPF
344 LNA
346 Mixer 348 ADC
362 BPF
364 Mixer 366 RRC filter 368 Hilbelt filter 369 Mixer 370 Maximum ratio synthesis unit 372 Correlation calculation unit 373 Reference branch determination unit 374 Weight coefficient calculation unit 376 Weight processing unit 378 Synthesis unit 390 Delay detection unit 392 Demodulation unit S1 Input switch S2 Output switch

Claims (6)

Multiple branches that perform signal processing on the received signal corresponding to each,
A correlation calculation unit that calculates the autocorrelation value of the processing signal of each branch and the mutual correlation value between the processing signals of each branch from the processing signal of each branch.
A reference branch determination unit that determines the branch having the maximum autocorrelation value from the plurality of branches as a reference branch,
A coefficient output unit that outputs a weight coefficient without phase compensation of the processing signal of the reference branch based on the cross-correlation value, and a coefficient output unit.
A weighting processing unit that weights the processing signal of each branch using the weighting coefficient output by the coefficient output unit, and a weighting processing unit.
A compositing unit that synthesizes the processing signals of each branch weighted by the weighting processing unit, and a compositing unit.
A wireless device. The coefficient output unit includes a plurality of weight coefficient calculation units, and an output switch located between the plurality of weight coefficient calculation units and the weighting processing unit.
Each weight coefficient calculation unit included in the plurality of weight coefficient calculation units calculates a weight coefficient with phase compensation of the processing signal of the other branch without phase compensation of the processing signal of one branch.
The wireless device according to claim 1, wherein the output switch connects a weight coefficient calculation unit that calculates a weight coefficient without phase compensation of a processing signal of a branch determined as the reference branch and the weight processing unit. The coefficient output unit further includes an input switch located between the correlation calculation unit and the plurality of weight coefficient calculation units.
The input switch according to claim 1 or 2, wherein the input switch connects the correlation calculation unit and a weight coefficient calculation unit that calculates a weight coefficient without phase compensation of the processing signal of the branch determined as the reference branch. Wireless device. The weight coefficient calculation unit has one eigenvector of a correlation matrix having an autocorrelation value of the processed signal of each branch as a diagonal component and a cross-correlation value between the processed signals of each branch as an off-diagonal component. The wireless device according to claim 2 or 3, which is calculated as a weight coefficient. The wireless device according to any one of claims 1 to 4, wherein each branch includes an antenna, a filter, an AD converter, and a mixer. The wireless device according to claim 5, wherein the processed signal of the branch is a signal obtained by subjecting the received signal received by the antenna to signal processing including filtering, AD conversion, and down conversion.

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