JP2007116414A - Radio communication apparatus and radio communication method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a radio communication apparatus capable of detecting a weight generation error generated during communication. <P>SOLUTION: The radio communication apparatus is provided with: a plurality of antenna elements 201 for receiving a radio signal; an RF receiving part 203 for converting the radio signal into a receiving baseband signal; a propagation path estimation part 204 for estimating a propagation path response matrix from the receiving baseband signal; a receiving weight multiplication part 205 for preparing receiving weight from the propagation path response matrix and multiplying the receiving baseband signal by the receiving weight; and a weight generation error detection part 209 for detecting a weight generation error from the receiving baseband signal after the multiplication of the receiving weight. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a wireless communication apparatus that performs beamforming communication using a plurality of antenna elements.

  In recent years, using a wireless communication device having a plurality of antenna elements, a signal transmitted from each antenna element is multiplied by a complex weight, the amplitude and phase are individually controlled, a directional beam is created, and communication is performed. Attention is focused on technology. In the beamforming technology, transmission beamforming in which only a transmission-side wireless communication device forms a beam and performs communication, and transmission / reception beamforming in which both transmission and reception-side wireless communication devices form a beam and perform communication There is. Improve signal-to-noise power ratio (SNR) and signal-to-interference noise ratio (SINR: Signal-to-Interference and Noise power Ratio) during signal reception by using beamforming technology As a result, it is possible to improve communication quality and transmission speed, and expand the communicable distance.

In the beam forming technique, in order to obtain a desired beam pattern, the amplitude / phase distribution between a plurality of antenna elements must be as calculated. However, an actual wireless communication device includes a frequency converter and a high power amplifier (HPA) on the transmission side.
There are imperfections in the characteristics of various analog elements such as frequency converters on the receiving side, low noise amplifiers (LNA), filters, etc. I have it.

  Therefore, even if complex weight multiplication is performed without considering these effects and beam formation is performed, a desired beam pattern cannot be obtained. When a beam is formed by a radio communication device on the receiving side, even if there is an amplitude / phase deviation, it is not a big problem because the optimum weight including it can be applied at the time of reception and transmission. When a beam is formed by the wireless communication apparatus on the side, such an optimum weight cannot be applied at the time of transmission, so it is necessary to correct the amplitude / phase deviation between the antenna branches.

  Furthermore, when beam forming is performed using the relativity of propagation path responses between wireless communication apparatuses that perform transmission and reception, such as transmission and reception beam forming using singular value decomposition in a MIMO (Multi-Input Multi-Output) system. When determining the beam pattern using the propagation path response obtained in the reverse link, if there is the amplitude / phase fluctuation described above, the propagation path response from the first wireless communication apparatus to the second wireless communication apparatus Then, since the relativity of the propagation path response from the second wireless communication apparatus to the first wireless communication apparatus is not maintained, an efficient beam pattern cannot be formed. Therefore, it is necessary to correct the amplitude / phase deviation between the first wireless communication device and the second wireless communication device (see, for example, Non-Patent Document 1).

  In such a case, the characteristics of each analog element of each wireless communication device are measured and stored, and a weight that cancels the deviation of the characteristic is obtained, and this weight is multiplied by the transmission signal to correct the amplitude / phase deviation. It is generally done. Such a correction method is called “calibration”. Hereinafter, the weight for correcting the amplitude / phase deviation obtained as a result of the calibration is referred to as a calibration weight.

Also, it is known to perform calibration by transmitting and receiving a training signal including a known signal for propagation path estimation between two wireless communication devices that perform communication at the start of communication or data transmission (for example, patents) Reference 1).

  FIG. 11 is a diagram illustrating an example of a calibration procedure in a conventional wireless communication apparatus. This calibration is performed between the first wireless communication device and the second wireless communication device. In FIG. 11, communication from the first wireless communication device to the second wireless communication device is referred to as a forward link, and communication from the second wireless communication device to the first wireless communication device is referred to as a reverse link.

  The first wireless communication apparatus transmits a calibration request signal (step S1101). The second wireless communication apparatus that has received the calibration request signal transmits the first training signal (step S1102). The first training signal includes a known signal for estimating the reverse link propagation path response. The first wireless communication apparatus that has received the first training signal estimates the propagation path response of the reverse link (step S1103).

  Next, the first wireless communication apparatus transmits a second training signal (step S1104). The second training signal includes a known signal for estimating the forward link propagation path response. When the second wireless communication apparatus receives the second training signal, the second wireless communication apparatus estimates the forward link propagation path response (step S1105). The second wireless communication apparatus includes the estimated forward link propagation path response in the forward link response estimated value notification signal and transmits it to the first wireless communication apparatus (step S1106).

  At this time, since the first wireless communication apparatus has the estimated values of the propagation path responses of both the forward link and the reverse link, the calibration weight is calculated so that these satisfy the relativity (step S1107). The first wireless communication apparatus transmits a calibration weight used by the second wireless communication apparatus when transmitting the reverse link as a calibration weight notification signal to the second wireless communication apparatus (step S1108).

  In this way, the amplitude / phase deviation due to the analog element is corrected. However, if the amplitude / phase deviation of the analog element changes over time, the calibration matrix created at the start of communication or data transmission will have poor calibration accuracy, and the relativity of the channel response will be low. Since it cannot be maintained, the performance of the wireless communication device is deteriorated.

In such a case, calibration can be performed not only at the start of communication but at regular intervals, and the weight for correcting the amplitude / phase deviation can be updated to cope with fluctuations in the amplitude / phase deviation. In addition, the temperature inside the wireless communication device is monitored, and calibration is performed when the amount of temperature change during a certain period exceeds a predetermined threshold value. It is known to correspond (for example, refer to Patent Document 2).
Special table 2004-534456 gazette JP 2001-53661 A Motohiko Isaka, “Coding and Modulation in MIMO Channels”, IEICE Transactions, December 2003, Vol. J86-A, no. 12, p. 1292-1301

  However, when signals are transmitted / received by a wireless communication apparatus having a plurality of antenna elements, mutual coupling of the antenna elements occurs between the plurality of antenna elements. As a result, a signal component transmitted or received by a certain antenna element leaks into another antenna element, thereby generating an amplitude / phase deviation.

  In addition, signal components that leak into other antenna elements vary depending on the directivity inherent to the antenna elements, the arrangement of the antenna elements, the incident angle of the radio signal, etc., and the amplitude / phase deviation due to coupling between the antenna elements is also affected by this. . Therefore, if the direction of arrival of radio waves changes due to movement or changes in the surrounding environment, or if the angle of the antenna when using a wireless communication device changes, the amount of coupling between antenna elements changes, and the amount of amplitude and phase deviation changes. . In addition, when there is a conductor such as a human body or metal near the antenna, coupling occurs not only between the antenna elements but also between the antenna element and the conductor, so the amplitude / phase deviation amount changes. .

  As a result, the amplitude / phase deviation amount at the analog element changes from the start of communication during communication, and the calibration weight obtained at the start of communication cannot correct the amplitude / phase deviation, and the relativity of the propagation path response cannot be maintained. End up. When communication is continued in such a state, there is a problem that an increase in error rate in the wireless communication device and an increase in interference given to other wireless communication devices occur.

  The present invention solves the above-described conventional problems, and detects and corrects weight deviations due to amplitude and phase deviations during communication, thereby maintaining the relativity of propagation path responses and providing a radio signal with an efficient beam pattern. It is an object of the present invention to provide a wireless communication apparatus that can receive a message.

  In order to solve the above-described conventional problems, a wireless communication apparatus according to the present invention includes a plurality of antenna elements that receive wireless signals, an RF receiver that converts wireless signals into received baseband signals, and propagation from the received baseband signals. A propagation path estimator for estimating a path response matrix, a reception weight multiplier for creating a reception weight from the propagation path response matrix and multiplying the reception baseband signal by the reception weight, and a weight from the reception baseband signal after reception weight multiplication. A weight generation error detection unit that detects a generation error.

  According to this configuration, it is possible to detect that the amplitude / phase deviation amount has changed during communication using the beamforming technique as a weight generation error obtained from the received baseband signal. In this way, changes in the amplitude and phase deviation amount can be detected at any time during data reception, so that accurate beamforming communication can be realized.

  In the wireless communication apparatus of the present invention, it is preferable that the weight generation error detection unit detects a weight generation error by observing an imaginary component of the reception baseband signal after reception weight multiplication.

  According to this configuration, when there is no weight generation error, the received baseband signal after reception weight multiplication does not have an imaginary component term, so by observing this imaginary component, it is determined whether there is a weight generation error. Can be detected.

  In the wireless communication apparatus of the present invention, it is preferable that the weight generation error detection unit detects the weight generation error by observing the phase rotation of the reception baseband signal after reception weight multiplication.

  According to this configuration, when there is no weight generation error, there is no phase rotation in the received baseband signal after reception weight multiplication, and therefore, it is detected whether there is a weight generation error by observing this phase rotation. be able to.

In the wireless communication apparatus of the present invention, it is preferable that the weight generation error detection unit detects a weight generation error from a signal obtained by averaging a plurality of reception baseband signals after reception weight multiplication.

  According to this configuration, the noise component included in the signal vector after reception weight multiplication is averaged, and the influence of the noise component when detecting the weight generation error can be reduced. As a result, accuracy in weight generation error detection can be improved.

  In the wireless communication apparatus of the present invention, it is preferable that the weight generation error detection unit determines that there is a weight generation error when the weight generation error is a predetermined value or more.

  According to this configuration, it is possible to prevent erroneous determination of a weight generation error due to a noise component or the like. As a result, accuracy in weight generation error detection can be improved.

  A wireless communication device of the present invention includes a plurality of antenna elements that receive a radio signal, an RF receiver that converts a radio signal into a received baseband signal, and a propagation path estimator that estimates a propagation path response matrix from the received baseband signal And a weight generation error detector for acquiring an error detection matrix by multiplying the channel response matrix by a Hermitian transpose matrix of the channel response matrix and detecting a weight generation error from the error detection matrix.

  According to this configuration, it is possible to detect a weight generation error due to a change in the amplitude / phase deviation amount from the error detection matrix obtained from the propagation path response matrix during data reception. In this way, changes in the amplitude and phase deviation amount can be detected at any time during data reception, so that accurate beamforming communication can be realized.

  In the wireless communication apparatus of the present invention, it is preferable that the weight generation error detection unit determines that there is a weight generation error when the off-diagonal term component of the error detection matrix is a predetermined value or more.

  According to this configuration, when there is no weight generation error, no value appears in the off-diagonal term component of the error detection matrix, so by observing this off-diagonal term component, it is determined whether there is a weight generation error. Can be detected.

  In the wireless communication device of the present invention, it is preferable that the weight generation error detection unit determines that there is a weight generation error when the imaginary component of the diagonal term component of the error detection matrix is equal to or greater than a predetermined value.

  According to this configuration, when there is no weight generation error, an imaginary number component does not appear in the diagonal term of the error detection matrix, so it is possible to detect whether there is a weight generation error by observing this imaginary number component. it can.

  In the wireless communication apparatus of the present invention, it is preferable that the weight generation error detection unit determines that there is a weight generation error when the phase rotation of the diagonal term component of the error detection matrix is equal to or greater than a predetermined value.

  According to this configuration, when there is no weight generation error, phase rotation does not appear in the diagonal term of the error detection matrix, so it is possible to detect whether there is a weight generation error by observing this phase rotation.

  In the wireless communication apparatus of the present invention, it is preferable that the weight generation error detection unit detects a weight generation error using a matrix obtained by averaging a plurality of error detection matrices.

According to this configuration, when the propagation path response matrix is estimated by the propagation path estimation unit, the error component included in the matrix is averaged, and the influence of the error component in detecting the weight generation error can be reduced. As a result, accuracy in weight generation error detection can be improved.

  The radio communication apparatus of the present invention preferably further includes a training generation unit that generates a training signal for generating or updating weights, and the weight generation error detection unit notifies the weight generation error to the training generation unit.

  According to this configuration, calibration can be performed according to detection of a weight generation error. By doing in this way, the calibration that has been conventionally performed at the start of communication or at regular intervals can be performed according to the occurrence of a weight generation error, so that the accuracy of beamforming communication can be improved.

  In the wireless communication apparatus of the present invention, it is preferable that the training generation unit generates a training signal for estimating a channel response matrix using a weight generation error.

  According to this configuration, the transmitting-side wireless communication device that has received the training signal can estimate the propagation path response matrix after the amplitude / phase deviation amount change, and can generate the transmission weight matrix with high accuracy.

  In the wireless communication apparatus of the present invention, it is preferable that the training generation unit generate a training signal for calibrating the relativity of the channel response matrix using the weight generation error.

  According to this configuration, the wireless communication device on the transmission side that has received the training signal can perform calibration to maintain the duality of the propagation path of the forward link and the reverse link after the amplitude / phase deviation amount change. it can.

  In the wireless communication apparatus of the present invention, it is preferable that the training generation unit generates a training signal including an estimated value of the propagation path response matrix estimated by the propagation path estimation unit using the weight generation error.

  According to this configuration, the wireless communication device on the transmission side that has received the training signal uses the channel estimation value of the reverse link estimated from the training signal and the channel estimation value of the forward link included in the training signal. It is possible to obtain the calibration weight after the amplitude / phase deviation amount change.

  In the wireless communication apparatus of the present invention, it is preferable that the training generation unit generates a training signal including a calibration matrix using a weight generation error.

  According to this configuration, the transmitting-side wireless communication apparatus that has received the training signal can correct the amplitude / phase deviation using the calibration matrix included in the training signal.

  The wireless communication apparatus of the present invention further includes a calibration matrix multiplier between the RF receiver and the propagation path estimator, and the weight generation error detector detects the weight generation error when detecting the weight generation error. It is preferable to notify the calibration matrix multiplier, and the calibration matrix multiplier preferably multiplies the received baseband signal by a calibration weight.

According to this configuration, when detecting a weight generation error, the radio communication device on the reception side multiplies the received baseband signal by a calibration weight that minimizes the weight generation error, thereby changing the changed amplitude. -Phase deviation can be corrected. In this way, when the amplitude / phase deviation change occurs in the analog element of the reception-side wireless communication device, the amplitude / phase deviation can be changed without performing signal exchange with the transmission-side wireless communication device. Phase deviation can be corrected.

  In the wireless communication device of the present invention, the weight generation error detection unit trains the weight generation error when the weight generation error detection unit detects the weight generation error even after the calibration matrix multiplication unit multiplies the calibration weight. It is preferable to notify the generation unit.

  According to this configuration, it is possible to correct the amplitude / phase deviation of the wireless communication devices on the reception side and the transmission side.

  The wireless communication method of the present invention includes a step of receiving a wireless signal with a plurality of antenna elements, a step of converting the wireless signal into a received baseband signal, a step of estimating a propagation path response matrix from the received baseband signal, and a propagation A step of generating a reception weight from the path response matrix, multiplying the reception baseband signal by the reception weight, and a step of detecting a weight generation error from the reception baseband signal after reception weight multiplication.

  According to this configuration, it is possible to detect that the amplitude / phase deviation amount has changed during communication using the beamforming technique as a weight generation error obtained from the received baseband signal. In this way, changes in the amplitude and phase deviation amount can be detected at any time during data reception, so that accurate beamforming communication can be realized.

  According to the wireless communication device of the present invention, during beamforming communication, the amplitude / phase deviation between transmission / reception antenna branches in the wireless communication device performing transmission / reception changes, and the relativity of the wireless propagation path cannot be maintained, and weight generation is performed. Even if an error occurs, the error detection unit can detect a relative shift. Furthermore, when a relative shift is detected, by correcting the shift, it is possible to correct an amplitude / phase deviation between transmission / reception antenna branches and transmit / receive a radio signal with an efficient beam pattern.

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

(Embodiment 1)
FIG. 1 is a block diagram showing a configuration of a transmitting-side radio communication apparatus that performs beam forming and transmits a radio signal to the radio communication apparatus according to the first embodiment. The wireless communication apparatus includes an encoder 101, a distributor 102, 1 or more integer SS baseband modulators 103-1 to SS, a preamble signal generator 104, a preamble signal multiplexer 105, a transmission weight multiplier 106, The calibration matrix multiplying unit 107, one or more integer M RF transmitting units 108-1 to M, and M antenna elements 109-1 to M are provided.

  FIG. 2 is a block diagram showing a configuration of the wireless communication apparatus according to the first embodiment. The radio communication apparatus shown in FIG. 2 detects a weight generation error while receiving a beamformed radio signal from the transmission-side radio communication apparatus shown in FIG. 1, and performs calibration if there is a weight generation error. Perform

The wireless communication apparatus shown in FIG. 2 includes one or more integer N antenna elements 201-1 to 201-N, N transmission / reception changeover switches 202-1 to N, N RF receiving units 203-1 to N, and propagation paths. Estimator 204, received weight multiplier 205, SS baseband demodulators 206-1 to SS, combiner 207, decoder 208, weight generation error detector 209, training generator 210, N RF transmitters 211 -1 to N.

  In the wireless communication apparatus shown in FIG. 2, when only the reception weight is multiplied without multiplying the transmission weight, the transmission / reception changeover switches 202-1 to N, the training generation unit 210, and the RF transmission units 211-1 to N are Not a required configuration.

  The wireless communication apparatus shown in FIG. 2 generally has the configuration of the wireless communication apparatus shown in FIG. 1 as a matter of course. However, the wireless communication apparatus may have only the configuration shown in FIG. On the other hand, the wireless communication apparatus shown in FIG. 1 generally includes the RF receiving units 203-1 to 203-N and the propagation path estimating unit 204 shown in FIG.

  Hereinafter, in the first embodiment, the transmitting-side wireless communication apparatus shown in FIG. 1 is referred to as a transmitting terminal A, and the receiving-side wireless communication apparatus illustrated in FIG. In addition, the matrix used in the following description is defined as follows.

  Here, the amplitude / phase deviation received by each analog element is expressed in a matrix as an amplitude / phase deviation matrix, the calibration weight is expressed in a matrix as a calibration matrix, and before RF modulation of the radio communication device on the transmission side A BB (Baseband-to-Baseband) propagation path response matrix, a BB propagation path response matrix after calibration weight multiplication, representing the propagation path response of the receiving-side radio communication apparatus until after RF demodulation as a matrix. Is called a corrected propagation path response matrix.

  3 and 4 are diagrams showing the relationship of the matrix in the first embodiment. Further, the matrix satisfies the following equation (1).

  In transmission terminal A shown in FIG. 1, information bit sequence b (i) that is transmission data is encoded by encoder 101. Here, i = 1 to I represents an index of the information bit series, and I is an integer of 1 or more. The encoded bit sequence c (j) is distributed into SS pieces by the distributor 102. Here, j = 1 to J represents an index of the coded bit sequence, and J is an integer of 1 or more. The output of the distributor 102 is represented by an equation (2) as an SS × 1 bit stream vector.

  Here, k = 1 to K is a bit index of each stream, and K is an integer of 1 or more. The SS bit streams are baseband modulated by the baseband modulators 103-1 to 103-3 and become modulation symbols.

  Next, the preamble signal generated by preamble signal generation section 104 is multiplexed into a modulation symbol by preamble signal multiplexing section 105.

  FIG. 5 is a diagram showing a frame configuration when the preamble signal in the first embodiment is multiplexed before the modulation symbol. The SS preamble signal units 501-1 to SS shown in FIG. 5 are configured to be orthogonal to each other in any one of time, frequency, space, eigenvector space, code, and polarization.

  The SS × 1 modulation symbol vector after preamble multiplexing is expressed by Equation (3).

  Here, p = 1 to P represents modulation symbol indexes.

Transmission weight multiplication section 106 multiplies the preamble-multiplexed modulation symbol vector by a transmission weight matrix. The calibration matrix multiplication unit 107 multiplies the signal vector after the transmission weight multiplication by the calibration matrix K _{A, tx} . The signal after the calibration matrix multiplication is RF-modulated in the RF transmitters 108-1 to 108-M. At this time, the amplitude / phase deviation represented by the amplitude / phase deviation matrix C _{A, tx} is received. The signal after RF modulation is transmitted from antenna elements 109-1 to 109-M.

  Here, the transmission signal vector S is expressed by Expression (4).

  Further, the transmission signal vector S can be expressed by Expression (5).

Here, W _tx represents a transmission weight matrix (M × SS dimension) multiplied by the transmission weight multiplier 106.

  On the other hand, the receiving terminal B shown in FIG. 2 receives the radio signal transmitted from the transmitting terminal A by the antenna elements 201-1 to 201-N.

The received radio signal is converted into reception baseband signals r _{1 to} r _N by RF reception units 203-1 to 203-1 through transmission / reception changeover switches 202-1 to 202- _N . At this time, a received baseband signal vector r composed of N received baseband signal sequences is expressed by Equation (6).

  The received baseband signal vector r can be expressed by the following equation (7).

  Here, z represents an additive Gaussian noise vector.

  The propagation path estimation unit 204 uses the preamble signal unit included in the received baseband signal vector to generate a matrix.

Estimate Hereinafter, this matrix is referred to as a post-beamforming propagation path response matrix.

The reception weight multiplication unit 205 creates a reception weight matrix W _rx (SS × N dimension) from the post-beamforming propagation path response matrix estimated by the propagation path estimation unit 204 and multiplies the reception baseband signal vector r. The signal vector y after reception weight multiplication is represented by Expression (8).

  Further, the signal vector y after reception weight multiplication can be expressed by Equation (9).

  The elements of the signal vector y after reception weight multiplication are respectively baseband demodulated by the baseband demodulators 206-1 to 206-1, combined by the combiner 207 into one sequence, and decoded by the decoder 208.

Here, in the first embodiment, a transmission weight matrix based on singular value decomposition (SVD) of the propagation path response between the transmission terminal A and the reception terminal B is used as the transmission weight matrix W _tx . The transmission weight matrix W _tx is obtained by the following procedure.

  1) The transmitting terminal A sends a corrected propagation path response from the receiving terminal B to the transmitting terminal A.

Is estimated.

  2) Corrected channel response from the transmitting terminal A to the receiving terminal B by using the relationship of the above formula (1)

Is estimated.

  3) Corrected propagation path response given by the following equation (10)

Perform singular value decomposition of.

  Here, the diagonal elements of the N × M matrix Σ are

This singular value is expressed by the following equation (11).

λ _i is

Represents the i-th eigenvalue (i = 1, 2,..., N _{e in} descending order). N _e is equal to the smaller of M or N. All elements other than the diagonal of Σ are zero. In Equation (10), U is an N × N unitary matrix and each column is

Eigenvector, V is an M × M unitary matrix, and each column is

Represents the eigenvector of.

  4) Of the unitary matrix V,

The M × SS matrix V _SS composed of the eigenvectors up to the SSth of the.

5) Let the M × SS matrix V _SS be the transmission weight matrix W _tx .

  At this time, Expression (7) can be expanded as the following Expression (12).

Here, _ΣMXSS is an N × SS dimensional matrix composed of the first to _{SSth columns} of Σ, and I ₀ is an (M × SS) matrix expressed by the following equation (13).

In the first embodiment, the Hermitian transpose matrix of the post-beamforming propagation path response matrix is used as the reception weight matrix W _rx.

Is used. In this case, the signal vector y after reception weight multiplication is expressed by the following equation (14).

Here, Σ _SS is an SS × SS diagonal matrix composed of the first to SS-th rows of Σ _MXSS , and its diagonal elements are

The first to SSth singular values are taken.

From Equation (14), since Σ _SS ² is a diagonal matrix, each element of the signal vector y after reception weight multiplication is obtained by multiplying each element of the modulation symbol vector x by a real number.

Here, the amplitude / phase deviation matrix C _{B, rx} received by the reception RF units 203-1 to 203-N of the reception terminal B during communication is

Consider the case where At this time, Expression (7) is expressed by the following Expression (15).

  Here, using equation (16), the signal vector after reception weight multiplication

Is represented by the following equation (17).

  From equation (17), the product of all the matrices applied to the modulation symbol vector x is not diagonalized, and the signal vector after reception weight multiplication

Each element includes an inter-stream interference component.

The weight generation error detection unit 209 detects the weight generation error by observing the inter-stream interference component of the signal vector after reception weight multiplication. Specifically, the imaginary component of the signal vector after reception weight multiplication is observed. When the SNR is sufficiently high, when there is no weight generation error, the imaginary component of the signal vector after reception weight multiplication is small enough to be ignored.
However, when there is a weight generation error and the inter-stream interference component is included in the signal vector after reception weight multiplication, an imaginary component appears.

  Therefore, the weight generation error detection unit 209 determines that there is a weight generation error when the imaginary component of the signal vector after reception weight multiplication is larger than a predetermined value, and notifies the training generation unit 210 of the presence of the weight generation error. Output a signal.

  Further, in the examples given in Expression (15) and Expression (17), the amount of coupling between the antenna elements of the receiving terminal B is changed, and the amplitude / phase deviation matrix received by the RF receivers 203-1 to 203-N of the receiving terminal B is changed. Although the case where it changed is demonstrated as an example, not only in this case, but also the amplitude / phase deviation matrix received by the RF transmitting units 108-1 to M of the transmitting terminal A, and the amplitude / phase deviation matrix received by the RF receiving unit of the transmitting terminal A , Weight generation even when any one or any combination of four types of amplitude / phase deviation matrices of the amplitude / phase deviation matrix received by the RF transmitters 211-1 to 211 -N of the receiving terminal B, or any combination thereof is changed The error detection unit 209 can detect a weight generation error.

  The training generation unit 210 performs calibration and generates a training signal for updating weights when a signal notifying the presence of a weight generation error is sent from the weight generation error detection unit 209. The generated training signals are RF-modulated by the RF modulators 211-1 to 211 -N, and then transmitted from the antenna elements 201-1 to 201 -N through the transmission / reception changeover switches 202-1 to 202 -N. After this, calibration is performed according to step S1002 and subsequent steps of the calibration procedure described above.

  FIG. 6 is a diagram showing the procedure of the weight generation error detection process in the first embodiment. Receiving terminal B observes the imaginary component of the signal vector after reception weight multiplication by weight generation error detection section 209 (step S601). Next, the weight generation error detection unit 209 compares the imaginary component of the signal vector after reception weight multiplication with a predetermined value. If the imaginary number component of the signal vector after reception weight multiplication is smaller than the predetermined value (No in step S602), the process returns to step S601, and observation of the imaginary number component of the signal vector after reception weight multiplication is continued. On the other hand, when the imaginary component of the signal vector after reception weight multiplication is larger than the predetermined value (step S602, Yes), the weight generation error detection unit 209 determines that there is a weight generation error, and the training generation unit 210 receives the weight. The presence of a generation error is notified (step S603). Upon receiving the notification, the training generation unit 210 creates a training signal and transmits it to the transmission terminal A (step S604).

  According to such a configuration, the weight generation error can be detected during reception of the radio signal transmitted from the transmission terminal A. If there is a weight generation error, the training signal is transmitted to the transmission terminal A and the calibration is performed. The amplitude / phase deviation between the transmitting and receiving antenna branches changed by the coupling between the antenna elements can be corrected.

In the first embodiment, the reception weight W _rx is

Of the unitary matrix U shown in Equation (10),

Hermite transposed matrix of M × SS matrix U _SS composed of up to SS-th eigenvectors

May be used.

  At this time, the signal vector y after reception weight multiplication is expressed by the following equation (18).

In this equation, since Σ _SS is a diagonal matrix, each element of the signal vector y after reception weight multiplication is obtained by multiplying each element of the modulation symbol vector x by a real number. Also,

Since the norm of is 1,

Is a vector obtained by rotating the additive Gaussian noise vector z.

As reception weight W _rx

However, the reception weight obtained by the minimum mean square error criterion may be used. In this way, the mean square error between the signal vector after reception weight multiplication and the signal vector before transmission weight multiplication can be minimized. In this case, the reception weight W _rx is expressed by the following equation (19).

  At this time, the signal vector y after reception weight multiplication is expressed by the following equation (20).

Is a matrix with only diagonal components, so each element of the signal vector y after multiplication of the reception weight is a real multiple of each element of the modulation symbol vector x, and the imaginary number component of the signal vector after reception weight multiplication is observed Thus, a weight generation error can be detected.

Further, in the first embodiment, as the transmission weight matrix W _tx, it was used M × SS matrix V _SS, the average value of M × SS matrix V _SS

And the equation (21) given by the minimum mean square error criterion may be used as the reception weight matrix.

  In this way, the mean square error between the signal vector after reception weight multiplication and the signal vector before transmission weight multiplication can be minimized. Also in this case, since the inter-stream interference component is minimized, the weight generation error can be detected by observing the imaginary component of the signal vector after reception weight multiplication.

In the first embodiment, weight generation error detection section 209 observes the imaginary component of the signal vector after reception weight multiplication, but may observe the phase rotation of the signal vector after reception weight multiplication. Since the inter-stream interference component appears as a phase rotation in the signal vector after reception weight multiplication, a weight generation error can be detected when the phase rotation of the signal vector after reception weight multiplication is greater than a predetermined value. . Of course, you may observe both the imaginary component and phase rotation of the signal vector after reception weight multiplication. By doing so, the accuracy of weight generation error detection can be further improved.

  In the first embodiment, the weight generation error detection unit 209 detects the weight generation error using the signal vector after reception weight multiplication. Alternatively, the weight generation error detection unit 209 may use an averaged signal vector after reception weight multiplication. Good. By doing so, the noise component included in the signal vector after reception weight multiplication is also averaged, and the influence of the noise component at the time of detecting the weight generation error can be reduced.

Further, in the first embodiment, transmitting terminal A uses preamble signal multiplexing section 105 to multiplex preamble signal sections 501-1 to SS with data signal sections 502-1 to SS shown in FIG. was multiplied by the transmission weight W _tx in part 106, after it has been multiplied by the transmission weight W _tx to the data signal portion 502-1~SS in transmission weight multiplying unit 106, a preamble signal portion 501-1~SS the preamble signal multiplexing unit 105 May be multiplexed. In this way, when the propagation path estimation unit 204 of the receiving terminal B estimates the propagation path response, the transmission weight W _tx is not applied to the preamble units 501-1 to SS, so the corrected propagation path response matrix

Can be estimated.

  In the first embodiment, as shown in FIG. 5, the preamble signal units 501-1 to SS are multiplexed before the data signal units 502-1 to SS. You may multiplex in the back and arbitrary positions in the data signal part 502-1 to SS.

  Further, in the first embodiment, the transmission terminal A is a propagation path estimator and the corrected propagation path response from the reception terminal B to the transmission terminal A

However, first, the transmitting terminal A transmits the BB propagation path response from the receiving terminal B to the transmitting terminal A.

, And then _{multiply this} by _{KB, tx} that the transmitting terminal A has in advance, and the corrected channel response

It is good also as a structure which estimates. By doing in this way, a correction | amendment propagation path response can be estimated from the signal transmitted without performing calibration.

  FIG. 7 is a block diagram showing another configuration of the wireless communication apparatus according to the first embodiment. This wireless communication apparatus includes one or more integer N antenna elements 201-1 to 201-N, N transmission / reception changeover switches 202-1 to N, N RF reception units 203-1 to N, and a propagation path estimation unit 204. , Reception weight multiplication section 205, SS baseband demodulators 206-1 to SS, combiner 207, decoder 208, weight generation error detection section 209, training generation section 210, N RF transmission sections 211-1 to 211-1. N, a switch 701, and a calibration matrix multiplier 702.

  Hereinafter, in the first embodiment, the receiving-side wireless communication apparatus shown in FIG.

  In the receiving terminal B, when the weight generation error detection unit 209 detects the weight generation error, the weight generation error detection unit 209 notifies the training generation unit 210 of a signal notifying the presence of the weight generation error, and the training generation unit 210 transmits the training signal to the transmission terminal A. However, in the receiving terminal C, when the weight generation error detecting unit 209 detects the weight generation error, the receiving terminal C sends a signal notifying the presence of the weight generation error to the switch 701.

  The switch 701 sends a notification signal to the calibration matrix multiplication unit 702. The calibration matrix multiplication unit 702 multiplies the calibration matrix. Even when the signal is received after the calibration matrix multiplication by the calibration matrix multiplication unit 702, if the weight generation error detection unit 209 detects a weight generation error, the switch 701 sends a notification signal to the training generation unit 201. The training generation unit 201 generates a training signal and transmits it to the transmission terminal A.

  In this way, when the weight generation error is caused by a change in the amplitude / phase deviation matrix received by the RF receivers 203-1 to 203-N of the receiving terminal C, the change can be corrected. Further, when a weight generation error is detected even after the calibration matrix multiplication, the training signal is transmitted to the transmission terminal A, thereby changing the amplitude / phase deviation of the RF transmission units 108-1 to M of the transmission terminal A. Can be corrected. That is, changes in amplitude and phase deviation can be accurately corrected at each of the transmission terminal A and the reception terminal C.

(Embodiment 2)
FIG. 8 is a block diagram showing a configuration of the wireless communication apparatus according to the second embodiment. This wireless communication apparatus includes one or more integer N antenna elements 201-1 to 201-N, N transmission / reception changeover switches 202-1 to N, N RF reception units 203-1 to N, and a reception weight multiplication unit 205. SS baseband demodulators 206-1 to SS, combiner 207, decoder 208, weight generation error detector 209, training generator 210, N RF transmitters 211-1 to N, propagation path estimator 801. This wireless communication apparatus has a propagation path estimation unit 801 between a reception weight multiplication unit 205 and a weight generation error detection unit 209.

  The configuration of the wireless communication apparatus on the transmission side in the second embodiment is the same as that shown in FIG. Hereinafter, in the second embodiment, the transmitting-side wireless communication apparatus shown in FIG. 1 is referred to as a transmitting terminal A, and the receiving-side wireless communication apparatus illustrated in FIG. Note that the symbols used in Embodiment 1 are used as they are for symbols such as matrices.

  In the second embodiment, the received baseband signal vector r is expressed by the following equation (22).

  The propagation path estimation unit 801 uses the preamble signal part included in the received baseband signal vector to generate a post-beamforming propagation path response matrix.

And the estimated post-beamforming propagation path response matrix is sent to the weight generation error detector 209.

  The weight generation error detection unit 209 determines the Hermitian transpose matrix of the post-beamforming channel response matrix from the post-beamforming channel response matrix.

Is multiplied by the propagation path response matrix after beam formation. Further, the transmitting terminal A uses V _SS as the transmission weight matrix W _tx . The error detection matrix E _cal after Hermitian transpose matrix multiplication is expressed by the following equation (23).

Since Σ _SS ² is a diagonal matrix, no off-diagonal terms appear in the error detection matrix E _cal .

Here, the amount of coupling between the antenna elements of the receiving terminal D changes, and the amplitude / phase deviation matrix C _{B, rx} received by the RF receivers 203-1 to 203-N of the receiving terminal D is

Consider the case where At this time, the post-beamforming propagation path response matrix obtained by the propagation path estimation unit 801 is

Represented by

The singular value decomposition of is expressed by the following equation (24).

As a result, the error detection matrix E _cal is expressed by the following equation (25).

At this time, the error detection matrix E _cal is not a diagonal matrix, and a component (numerical value) appears in the off-diagonal term.

When the diagonal term component of the error detection matrix E _cal is larger than a predetermined value, the weight generation error detection unit 209 determines that there is a weight generation error and sends a signal notifying the existence of the weight generation error to the training generation unit 210. .

  That is, in the first embodiment, the equation (17)

In the second embodiment, the coefficient portion multiplied by x in Equation (17), that is, E _cal in Equation (25) is observed, so that the weight generation error detection accuracy is increased accordingly. Can do.

Further, in the example given by Expression (25), the amount of coupling between antenna elements of the receiving terminal D is changed, and the amplitude / phase deviation matrix received by the receiving RF circuits 203-1 to 203-N of the receiving terminal D is changed as an example. As described above, not only in this case, the amplitude / phase deviation matrix received by the transmission RF circuits 108-1 to N of the transmission terminal A, the amplitude / phase deviation matrix received by the reception RF circuit of the transmission terminal A, The weight generation error detection unit 209 detects a weight generation error even when any or all of the four types of amplitude / phase deviation matrices of the amplitude / phase deviation matrix received by the transmission RF circuit change or all change. it can.

  When a signal notifying the presence of a weight generation error is sent from the weight generation error detection unit 209, the training generation unit 210 generates a training signal for performing calibration. The generated training signals are RF-modulated by the RF modulators 211-1 to 211 -N, and then transmitted from the antenna elements 201-1 to 201 -N through the transmission / reception changeover switches 202-1 to 202 -N.

  FIG. 9 is a diagram illustrating a procedure of weight generation error detection processing according to the second embodiment. In the receiving terminal D, the propagation path estimation matrix 801 estimates a post-beamforming propagation path response matrix (step S901). Next, the weight generation error detection unit 209 obtains an error detection matrix by calculating a Hermitian transpose matrix of the post-beamforming propagation path response matrix and multiplying the post-beamforming propagation path response matrix (step S902). Next, the weight generation error detection unit 209 compares the non-diagonal term component of the error detection matrix with a predetermined value. If the off-diagonal term component of the error detection matrix is smaller than the predetermined value (step S903, No), the process returns to step S901. On the other hand, if the off-diagonal term component of the error detection matrix is larger than the predetermined value (step S903, Yes), it is determined that there is a weight generation error, and the weight generation error detection unit 209 sends the weight generation error to the training generation unit 210. Is present (step S904). Upon receiving the notification, the training generation unit 210 creates a training signal and transmits it to the transmission terminal A (step S905).

  According to such a configuration, the weight generation error can be detected from the post-beamforming propagation path response matrix estimated by the propagation path estimation unit 801 during reception of the radio signal transmitted from the transmission terminal A. The training signal is transmitted to the transmission terminal A to execute calibration, and the amplitude / phase deviation between the transmission / reception antenna branches changed during communication can be corrected.

In the second embodiment, the weight generation error detection unit 209 detects the weight generation error by observing the off-diagonal component of the error detection matrix E _cal , but the error detection matrix E observed at a plurality of times. _You may observe the component of the off-diagonal term although _cal is averaged. By doing so, when the propagation path response matrix after beam forming is estimated by the propagation path estimation unit 801, the error components included in the matrix are averaged, and the influence of the error components in detecting the weight generation error is reduced. it can.

Further, in Embodiment 2, although the weight generation error detecting unit 209 has observed the components of the non-diagonal terms of the error detection matrix E _cal, even by observing the imaginary component of the diagonal elements of the error detection matrix E _cal Good. When there is no weight generation error, since the diagonal term of E _cal takes only a real number, the weight generation error can be detected in this way.

Further, in Embodiment 2, although the weight generation error detecting unit 209 has observed the components of the non-diagonal terms of the error detection matrix E _cal, even by observing the phase rotation of the diagonal terms of the error detection matrix E _cal Good. In the case where there is no weight generation error, the diagonal term of E _cal does not rotate in phase, and thus the weight generation error can be detected.

In the second embodiment, the weight generation error detection unit 209 observes two or more of the off-diagonal term component, the diagonal imaginary component, and the diagonal phase rotation of the error detection matrix E _cal. The weight generation error may be detected. By doing so, the accuracy of weight generation error detection can be improved.

  In the second embodiment, receiving terminal D may also have the configuration of receiving terminal C shown in FIG.

  Further, in the second embodiment, an error detection matrix acquisition unit is provided between the propagation path estimation unit 801 and the weight generation error detection unit 209, and the Hermitian transpose matrix is added to the propagation path response matrix by the error detection matrix acquisition unit. To obtain an error detection matrix, and the weight generation error detection unit 209 may detect the weight generation error from the error detection matrix.

  In the wireless communication apparatus of the present invention, when the training generation unit 210 receives a signal notifying the presence of a weight generation error from the weight generation error detection unit 209, the training generation unit 210 includes a training signal including a known signal for channel response estimation. A signal is generated and transmitted to the transmission terminal A, for example, an ACK packet, a NACK packet, a retransmission request packet, a data transmission packet, a propagation path estimation packet, a calibration control packet, and the like so as to be transmitted. It may be. By doing in this way, the transmission terminal A that has received the signal including the training signal can estimate the propagation path response and improve the generation accuracy of the transmission weight matrix. Furthermore, by transmitting a training signal, calibration can be executed according to the calibration procedure.

  In the wireless communication apparatus of the present invention, when the weight generation error detection unit 209 detects a weight generation error, the training generation unit 210 generates a calibration request signal and transmits it to the transmission terminal A. good. In this way, when a weight generation error is detected, the calibration procedure can be executed in order from step S1001.

  In the wireless communication apparatus of the present invention, when a weight generation error is detected by the weight generation error detection unit 209, a training signal may be generated including the propagation path response estimated by the propagation path estimation unit 801. In this way, the transmission terminal A that has received the training signal can execute the calibration procedure from step S1007.

  Also, in the wireless communication apparatus of the present invention, when a weight generation error is detected by the weight generation error detection unit 209, calibration is performed according to the calibration procedure described above. However, the present invention is not limited to this, and it is also possible to use another type of calibration procedure in which a training signal is transmitted and received between two wireless communication devices that perform communication.

    FIG. 10 is a diagram showing an example of another procedure of calibration in the second embodiment. For example, calibration may be performed according to the procedure shown in FIG. In the example of FIG. 10, the first wireless communication apparatus transmits a calibration request / training signal that serves as both a calibration request signal and a training signal (step S1001). The calibration request / training signal includes a known signal for estimating the forward link propagation path response. The second wireless communication apparatus that has received the calibration request / training signal estimates the propagation path response of the forward link (step S1002).

  Next, the second wireless communication apparatus transmits a training / forward link response estimated value notification signal (step S1003). The training / forward link response estimated value notification signal includes a known signal for estimating the reverse link propagation path response and the estimated forward link propagation path response. Upon receiving the training / forward link response estimated value notification signal, the first wireless communication apparatus estimates a reverse link propagation path response (step S1004).

  At this time, since the first wireless communication apparatus has the estimated values of the propagation path responses of both the forward link and the reverse link, it calculates the calibration weight so that these satisfy the relativity (step S1005). The first wireless communication apparatus transmits a calibration weight used by the second wireless communication apparatus at the time of reverse link transmission to the second wireless communication apparatus as a calibration weight notification signal (step S1006).

  As described above, in the wireless communication apparatus of the present invention, it is preferable to use a calibration procedure of a type in which the transmitting and receiving wireless communication apparatuses exchange training signals on the same frequency channel.

  In the wireless communication apparatus of the present invention, a multicarrier signal may be used as a wireless signal. In this way, detection of weight generation errors can be performed for each subcarrier, and beamforming communication can be effectively realized in a frequency selective fading environment. In this case, the weight generation error may be detected using only some of the subcarriers instead of all of the subcarriers. Further, subcarriers with a high reception level may be selected and used as some subcarriers for detecting the weight generation error. By doing in this way, the influence of the noise at the time of weight generation error detection can be reduced, and the accuracy of weight generation error detection can be improved.

  In addition, the wireless communication apparatus of the present invention may further include wireless signal arrival direction estimation means, and may detect a weight generation error when the arrival direction changes. In this way, when one or a plurality of strong radio waves arrive from a specific direction, the coupling between the direction-dependent antenna elements changes due to the change in the arrival direction. Thereby, even if the amplitude / phase deviation amount changes, the weight generation error can be detected in accordance with the change.

  In the wireless communication apparatus of the present invention, the weight generation error may be detected when the voice call and the data communication are switched. By doing so, it is possible to cope with changes in the amplitude and phase deviation caused by the amount of coupling between the antenna and the human body (human body proximity effect) due to the difference in the distance between the terminal and the human body during voice communication and data communication. Thus, the weight generation error can be detected.

  In the wireless communication device of the present invention, the weight generation error detection unit causes the weight generation error detection unit to change the amplitude / phase deviation between the transmission / reception antenna branches and maintain the relativity of the propagation path response. Can be transmitted and received with an efficient beam pattern. The wireless communication apparatus of the present invention is useful in a system that performs beam forming to communicate between wireless communication apparatuses having a plurality of antenna elements. Specifically, the present invention can be applied to mobile terminals and access points in a wireless LAN system, and mobile terminals and base stations in a cellular mobile communication system.

FIG. 1 is a block diagram showing a configuration of a transmission-side radio communication apparatus in Embodiment 1 of the present invention. 1 is a block diagram showing a configuration of a wireless communication apparatus according to a first embodiment of the present invention. The figure which shows the relationship of the matrix which concerns on the signal transmission from the radio | wireless communication apparatus of the transmission side in Embodiment 1 of this invention to the radio | wireless communication apparatus of the transmission / reception side. The figure which shows the relationship of the matrix which concerns on the signal transmission from the radio | wireless communication apparatus of the transmission / reception side to the radio | wireless communication apparatus of a transmission side in Embodiment 1 of this invention. The figure which shows the flame | frame structure at the time of multiplexing the preamble signal in Embodiment 1 of this invention before the modulation symbol. The figure which shows the procedure of the detection process of the weight production | generation error in Embodiment 1 of this invention. The block diagram which shows another structure of the radio | wireless communication apparatus of Embodiment 1 of this invention. FIG. 2 is a block diagram showing a configuration of a wireless communication apparatus according to a second embodiment of the present invention. The figure which shows the procedure of the detection process of the weight production | generation error in Embodiment 2 of this invention. The figure which shows the example of another procedure of the calibration in Embodiment 2 of this invention The figure which shows the example of the procedure of the calibration in the conventional radio | wireless communication apparatus

Explanation of symbols

DESCRIPTION OF SYMBOLS 201 Antenna element 202 Transmission / reception changeover switch 203 RF receiving part 204,801 Channel estimation part 205 Reception weight multiplication part 206 Baseband demodulator 207 Combiner 208 Decoder 209 Weight generation error detection part 210 Training generation part 211 RF transmission part 701 switch 702 Calibration matrix multiplication unit

Claims (18)

A plurality of antenna elements for receiving radio signals;
An RF receiver that converts the radio signal into a received baseband signal;
A channel estimator for estimating a channel response matrix from the received baseband signal;
A reception weight multiplier that creates a reception weight from the propagation path response matrix and multiplies the reception baseband signal by the reception weight; and
A weight generation error detector for detecting a weight generation error from the reception baseband signal after reception weight multiplication;
A wireless communication device comprising: The radio communication apparatus according to claim 1, wherein the weight generation error detection unit detects the weight generation error by observing an imaginary component of the reception baseband signal after reception weight multiplication. The radio communication apparatus according to claim 1, wherein the weight generation error detection unit detects the weight generation error by observing a phase rotation of the reception baseband signal after reception weight multiplication. 4. The radio according to claim 1, wherein the weight generation error detection unit detects the weight generation error from a signal obtained by averaging a plurality of the reception baseband signals after reception weight multiplication. 5. Communication device. The radio communication apparatus according to claim 1, wherein the weight generation error detection unit determines that there is the weight generation error when the weight generation error is equal to or greater than a predetermined value. A plurality of antenna elements for receiving radio signals;
An RF receiver that converts the radio signal into a received baseband signal;
A channel estimator for estimating a channel response matrix from the received baseband signal;
A weight generation error detector for multiplying the propagation path response matrix by a Hermitian transpose matrix of the propagation path response matrix to obtain an error detection matrix, and detecting a weight generation error from the error detection matrix;
A wireless communication device comprising: The wireless communication apparatus according to claim 6, wherein the weight generation error detection unit determines that there is a weight generation error when a non-diagonal term component of the error detection matrix is equal to or greater than a predetermined value. The wireless communication apparatus according to claim 6, wherein the weight generation error detection unit determines that there is a weight generation error when an imaginary component of a diagonal term component of the error detection matrix is a predetermined value or more. The wireless communication apparatus according to claim 6, wherein the weight generation error detection unit determines that there is a weight generation error when a phase rotation of a diagonal term component of the error detection matrix is a predetermined value or more. The wireless communication apparatus according to claim 6, wherein the weight generation error detection unit detects the weight generation error using a matrix obtained by averaging a plurality of the error detection matrices. A training generator for generating a training signal for generating or updating weights;
The radio communication apparatus according to claim 1, wherein the weight generation error detection unit notifies the weight generation error to the training generation unit. The wireless communication apparatus according to claim 11, wherein the training generation unit generates a training signal for estimating the propagation path response matrix using the weight generation error. The wireless communication apparatus according to claim 11, wherein the training generation unit generates a training signal for calibrating relativity of the propagation path response matrix using the weight generation error. The radio communication apparatus according to claim 11, wherein the training generation unit generates the training signal including the estimated value of the channel response matrix estimated by the channel estimation unit using the weight generation error. The wireless communication apparatus according to claim 11, wherein the training generation unit generates the training signal including a calibration matrix using the weight generation error. A calibration matrix multiplication unit is further provided between the RF receiving unit and the propagation path estimation unit, and the weight generation error detection unit converts the weight generation error into the calibration matrix when the weight generation error is detected. Notify the multiplier,
The wireless communication apparatus according to claim 1, wherein the calibration matrix multiplication unit multiplies the reception baseband signal by a calibration weight. Even when the calibration matrix multiplication unit multiplies the calibration weight, when the weight generation error detection unit detects the weight generation error, the weight generation error detection unit converts the weight generation error into the training generation. The wireless communication device according to claim 16, which notifies the unit. Receiving wireless signals with a plurality of antenna elements;
Converting the radio signal into a received baseband signal;
Estimating a channel response matrix from the received baseband signal;
Creating a reception weight from the propagation path response matrix and multiplying the reception baseband signal by the reception weight;
Detecting a weight generation error from the reception baseband signal after reception weight multiplication;
A wireless communication method.

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