JP2007215043A - Wireless communication method and wireless communication apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wireless communication method and a wireless communication apparatus whereby the communication quality for a plurality of communication opposite parties is properly selected by forming a transmission beam when the same information is transmitted to the communication opposite parties and a whole communication capacity is increased by effectively utilizing a space resource and obtaining an array gain. <P>SOLUTION: A channel information acquisition circuit 105 acquires a channel response matrix of each communication opposite party. A transmission weight candidate arithmetic circuit 106 applies singular decomposition to the received channel response matrix to calculate characteristic vectors and characteristic values. A common transmission weight arithmetic circuit 107 uses two or more of obtained characteristic vectors, multiplies a correction value with the characteristic vectors, and determines the summed vectors as a common transmission weight whereby variations of received power estimated by each communication opposite party are made constant. Thus, the common transmission weight can be determined, whereby the transmission quality closer to each communication opposite party is attained. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention uses the same frequency channel, spatially multiplexes and transmits independent signal sequences from a plurality of different transmission antennas, receives signals using a plurality of reception antennas, and obtains a channel response matrix between the transmission and reception antennas. In a high-speed wireless access system that uses MIMO (Multiple-Input Multiple-Output) communication that demodulates data on the receiving station side and simultaneously transmits information to multiple communication partners, In addition, the present invention relates to a wireless communication method and a wireless communication apparatus that transmit the same information.

  In recent years, the IEEE802.11g standard, the IEEE802.11a standard, and the like are remarkable as high-speed wireless access systems using the 2.4 GHz band or the 5 GHz band (for example, Non-Patent Document 1). In these systems, an orthogonal frequency division multiplexing (OFDM) modulation method, which is a technique for stabilizing characteristics in a multipath fading environment, is used, and a transmission rate of 54 Mbps at the maximum is realized. However, the transmission rate here is the transmission rate on the physical layer, and the transmission efficiency in the MAC (Medium Access Control) layer is actually about 50 to 70%, so the upper limit of the actual throughput is It is about 30 Mbps. Such a decrease in actual throughput is due to the fact that the terminal station does not transmit while the base station is transmitting, and that each terminal station takes the back-off time after the transmission is completed. . In considering future wireless communication, it is assumed that the terminal station performs directivity control and performs transmission by complex scheduling. In such a case, a decrease in throughput due to the MAC layer causes a decrease in overall communication quality. This will greatly hinder improvement.

  A MIMO technology that includes a plurality of antenna elements in each of the transmission device and the reception device and performs communication is effective in improving frequency utilization efficiency. This MIMO technology is such that different independent signals are transmitted on the same channel from a plurality of transmitting antennas on the transmitting station side, and signals are received using the same plurality of antennas on the receiving station side, between each transmitting antenna / receiving antenna. The channel response matrix is obtained, the independent signal transmitted from each antenna is estimated on the transmitting station side using this matrix, and the data is reproduced.

In FIG. 7, the number of antenna elements of the transmitting apparatus is M _T , the number of antenna elements of the receiving apparatus that is the communication partner is M _R , and the number of communication sequences transmitted simultaneously in the same frequency band is L. Indicates sex control. FIG. 7 is a configuration example of a transmission unit in the prior art that controls transmission directivity so as to be optimal for a propagation environment and performs spatial multiplexing to improve the transmission rate.

7, reference numeral 900 is a data dividing circuit, 901-1~901-L is a modulation circuit, _{903-1~903-M T} wireless unit, _{904-1~904-M T} is the antenna element, 905 channel response A matrix acquisition circuit 906 is an antenna selection determination circuit.

Antenna element _{904-1~904-M T} and the radio part _{903-1~903-M T} is capable of transmitting and receiving radio signals, each of the transmission unit via these antennas 904-1～904- the channel response matrix between the antennas of the communication partner M _T can be estimated in the channel response matrix acquiring circuit 905.

Although this method obtains the channel response matrix is not specified here, the feedback included in the estimate based on whether or received signal information obtained when performing the reception of the known signal in the antenna 904-1~904-M _T Information on the channel response matrix is acquired based on the information included in the information.

  When the communication partner that transmits the same information is determined, the channel response matrix acquisition circuit 905 acquires the channel response matrix of the corresponding communication partner, and this information is input to the antenna selection determination circuit 906, and is used for transmission. To decide.

For data to be transmitted, one signal is divided into L signal series in the data dividing circuit 900 and input to the modulation circuits 901-1 to 901 -L. Here, after a preamble signal and the like for MIMO channel estimation are given and modulated, these signals are input to an antenna selection circuit (not shown). Here, the transmission data is input to the radio section 903-1~903-M _T of the selected antenna, and transmitted as a radio signal through the selected antenna.

The k-th communication partner channel response matrix H _k (M _R (k) × M _T matrix) obtained in the channel response matrix acquisition circuit 905 can be expressed by the following equation.

Here, H _{k, ab} represents a channel response matrix from the b-th antenna of the transmission device to the a-th antenna of the reception device.

Here, it is considered that two communication sequences X = (x ₁ , x ₂ ) ^T are transmitted to two communication partners using the first antenna and the second antenna. () ^T represents a transposed matrix. Each of the two communication partners has two receiving antennas. The received signal Y ₁ = (y _1,1 , y _1,2 ) of the first communication partner, the received signal Y ₂ = (y _2,1 , y _2,2 ) of the second communication partner is selected Using the selected channel response matrix H ^s _k (2 × 2 matrix) between the transmitting antenna and the receiving antenna of the communication partner, it can be expressed as follows.

Each communication partner estimates the transmitted signal using the received signal. For example the inverse matrix and the selected channel response matrix to the received signal _{Y k,} and a method called ZF (Zero Forcing) method for multiplying a pseudo-inverse matrix, or MMSE (Minimum Mean Square Error) method, MLD (Maximum Likelihood Detection) method or the like Can be used to decode the transmission signal X.
Supervised by Masahiro Morikura and Shuji Kubota, “Revised 802.11 High-Speed Wireless LAN Textbook”, 2004

  However, when a signal is transmitted by such control, there are some problems as described below, which are the same whether the signal sequence to be transmitted is two or more or one.

1. It is necessary to set the amount of information of the transmission signal X to be low according to the communication partner with poor communication quality. If there is a large difference in the absolute value or eigenvalue distribution of the channel response matrix selected by each communication partner, the throughput is greatly reduced. To do.

2. Since the signal is radiated to the entire space, the space resources are used up, and it is difficult to perform other communications using the remaining spatial channels.

3. Even if the transmission / reception apparatus has many antenna elements, a large increase in throughput cannot be expected unless the number of receiving antennas of the communication partner is small.

  The present invention has been made in view of such circumstances, and when transmitting the same information to a plurality of communication partners, by forming a transmission beam, the communication quality for the communication partner is appropriately selected and effectively It is an object of the present invention to provide a wireless communication method and a wireless communication apparatus that increase the overall communication capacity by obtaining an array gain using spatial resources.

  The present invention according to claim 1 includes a plurality of antenna elements, estimates a channel response matrix representing a propagation environment between antennas of communication partners, determines a transmission weight, and performs transmission weighting on a transmission signal A wireless communication method for transmitting the same transmission signal to a plurality of communication partners, and calculating an eigenvector and an eigenvalue obtained from a transmission side correlation matrix of a channel response matrix corresponding to the communication partner transmitting common data. And a step of using two or more of the obtained eigenvectors, multiplying each by a correction value, and determining the added vector as a common transmission weight.

  The present invention according to claim 2 includes a plurality of antenna elements, estimates a channel response matrix representing a propagation environment between antennas of communication partners, determines a transmission weight, and performs transmission weighting on a transmission signal A wireless communication method for transmitting the same transmission signal to a plurality of communication partners, and calculating an eigenvector obtained from a transmission side correlation matrix of a channel response matrix corresponding to a communication partner transmitting common data; Estimating the received signal received by the other communication partner when using the eigenvalue for the communication partner from the inner product value, and correcting to the selected eigenvector so that the same received signal is received by each communication partner And a step of multiplying values, adding together, and determining a common transmission weight.

  The present invention according to claim 3 includes a plurality of antenna elements, estimates a channel response matrix representing a propagation environment between antennas of communication partners, determines a transmission weight, and performs transmission weighting on a transmission signal A wireless communication method for transmitting the same transmission signal to a plurality of communication partners, and calculating an eigenvector and an eigenvalue obtained from a transmission side correlation matrix of a channel response matrix corresponding to the communication partner transmitting common data. A step of determining which eigenvector to use for each communication partner, a step of determining an inner product value of the eigenvector determined to be used for a certain communication partner, and an eigenvector of the other communication partner, and an inner product value Estimate the received signal received by the other communication partner when using the eigenvalue for a certain communication partner, and the equivalent received signal for each communication partner A step of multiplying the selected eigenvector by a correction value and adding together to determine a common transmission weight, and a reception beam of the reception side device when using the common transmission weight obtained from the channel response matrix. A wireless communication method comprising: calculating an orthogonal spatial channel response matrix composed only of components orthogonal to each other; and determining again as a second transmission weight using the orthogonal spatial channel response matrix is there.

  The present invention according to claim 4 is the wireless communication method according to claim 3, wherein a common transmission weight is calculated from a channel response matrix, an orthogonal spatial channel response matrix is calculated from the common transmission weight and the channel response matrix, and orthogonal A second common transmission weight is calculated from the spatial channel response matrix, a second orthogonal spatial channel response matrix is calculated from the second common transmission weight and the orthogonal spatial channel response matrix, and from the second orthogonal spatial channel response matrix, A wireless communication method is characterized in that a third common transmission weight is calculated and the above processing is repeated to determine transmission weights for an arbitrary number of communication sequences.

  The present invention according to claim 5 includes a plurality of antenna elements, estimates a channel response matrix representing a propagation environment between antennas of communication partners, determines a transmission weight, and performs transmission weighting on a transmission signal A wireless communication method for transmitting the same transmission signal to a plurality of communication partners, dividing the communication partners transmitting the same information into the same group, and dividing the communication partners to be transmitted into a plurality of groups; When determining the transmission weight to a certain group, the step of defining an interference space basis vector from the channel response matrix of the communication partner not belonging to the group and the channel response matrix of the communication partner of the group A step of calculating an orthogonal spatial channel response matrix that is an orthogonal component with respect to a spatial basis vector, and a communication partner that transmits common data The eigenvector obtained from the transmission side correlation matrix of the corresponding orthogonal spatial channel response matrix, the step of calculating the eigenvalue, the step of determining which eigenvector to use for each communication partner, and the use for a certain communication partner are determined. The inner product value of the other eigenvector and the eigenvector of the other communication partner, and when the eigenvalue for the communication partner is used from the inner product value, the received signal received by the other communication partner is estimated and equal to each communication partner And a step of multiplying a selected eigenvector by a correction value so as to receive the received signal and adding the correction values to determine a common transmission weight.

  The present invention according to claim 6 includes a plurality of antenna elements, estimates a channel response matrix representing a propagation environment between antennas of communication partners, determines a transmission weight, and performs transmission weighting on a transmission signal A wireless communication method for transmitting the same transmission signal to a plurality of communication partners, dividing the communication partners transmitting the same information into the same group, and dividing the communication partners to be transmitted into a plurality of groups; When determining the transmission weight to a certain group, the step of defining an interference space basis vector from the channel response matrix of the communication partner not belonging to the group and the channel response matrix of the communication partner of the group A step of calculating an orthogonal spatial channel response matrix that is an orthogonal component with respect to a spatial basis vector, and a communication partner that transmits common data The eigenvector obtained from the transmission side correlation matrix of the corresponding orthogonal spatial channel response matrix, the step of calculating the eigenvalue, the step of determining which eigenvector to use for each communication partner, and the use for a certain communication partner are determined. A step of obtaining the inner product value of the eigenvector of the other communication partner and the other communication partner, and estimating the received signal received by the other communication partner when the eigenvalue for the communication partner is used from the inner product value. Multiplying the selected eigenvectors by a correction value so as to receive an equivalent received signal, adding together, and determining a common transmission weight, and the obtained common transmission weight of the orthogonal spatial channel response matrix of the group A second orthogonal spatial channel response matrix consisting only of components orthogonal to the received beam of the receiving apparatus when using A step of computing, using a quadrature spatial channel response matrix, which is a wireless communication method characterized by again comprises determining a second common transmission weight, a.

  The present invention according to claim 7 is the radio communication method according to claim 6, wherein a common transmission weight is calculated from an orthogonal spatial channel response matrix of communication partners belonging to the group, and the common transmission weight and the orthogonal spatial channel response matrix are calculated. A second orthogonal spatial channel response matrix is calculated from the second orthogonal spatial channel response matrix, a second common transmission weight is calculated from the second orthogonal spatial channel response matrix, and a third is calculated from the second common transmission weight and the second orthogonal spatial channel response matrix. And calculating the third common transmission weight from the third orthogonal spatial channel response matrix and repeating the above processing to determine the transmission weight of an arbitrary number of communication sequences. A wireless communication method characterized by the above.

  The present invention according to claim 8 is the wireless communication method according to claim 6, wherein when there is one communication partner corresponding to the group, an orthogonal spatial channel response matrix obtained for the communication partner Is a wireless communication method characterized in that a vector obtained by linear calculation is used as a transmission weight.

  According to a ninth aspect of the present invention, in the wireless communication method according to any one of the first to seventh aspects, the first eigenvector is selected as the eigenvector to be selected for each communication partner. is there.

  According to a tenth aspect of the present invention, in the wireless communication method according to any one of the first to seventh aspects, the wireless communication is characterized in that, as the eigenvector to be selected for each communication partner, one having a value close to the eigenvalue corresponding to the eigenvector is selected. Is the method.

The present invention according to claim 11 is constituted by a transmitting station having a plurality of antenna elements and a plurality of communication partner stations having one or a plurality of antenna elements. Via a MIMO (Multiple Input Multiple Output) channel composed of antenna elements or beams formed on these antenna elements, one or a plurality of signal sequences are sent to the same frequency channel and the same time for a plurality of communication counterpart stations. In a wireless communication apparatus that transmits common transmission data for M _u communication partners in a wireless communication system capable of performing spatially multiplexed MIMO communication, M _T (M _T > 1: integer) antennas Element and connected to each antenna element. To the channel information acquisition circuit, and at the time of transmission, a radio unit that transmits the transmission signal as a radio signal from the antenna element, and a channel response matrix for the communication partner is estimated from the signal input from the radio unit, and communication is performed. When the partner and the transmission signal are determined, each communication partner is based on the channel information acquisition circuit that outputs the channel response matrix of the communication partner to be transmitted to the transmission weight candidate calculation circuit, and the channel response matrix input from the channel information acquisition circuit. The transmission weight candidate calculation circuit for calculating the transmission weight candidate for the transmission weight and the transmission weight candidate for each communication partner output from the transmission weight candidate calculation circuit are multiplied by the correction value, added together, the transmission weight is determined, and the transmission signal is converted. Common output to the modulation circuit and data division circuit that is output to the circuit and applied to each communication series A transmission weight determination circuit composed of a transmission weight calculation circuit, the channel response matrix acquisition circuit, a transmission weight candidate calculation circuit, and a common transmission weight calculation circuit, and data division for dividing transmission data into the number of communication sequences according to the modulation method A circuit, a modulation circuit that modulates each signal series, and a transmission weight determined by a transmission weight calculation circuit for each modulated communication series, and outputs to a radio unit connected to the corresponding antenna element A wireless communication apparatus comprising a transmission signal conversion circuit.

  According to a twelfth aspect of the present invention, in the wireless communication device according to the eleventh aspect, the transmission weight determination block estimates a channel response matrix for a communication partner from a signal input from a wireless unit, and transmits the communication partner and a transmission signal. Is determined, a channel information acquisition circuit that outputs a channel response matrix of a communication partner to be transmitted to a transmission weight candidate calculation circuit, and a transmission obtained by singular value decomposition based on the channel response matrix input from the channel information acquisition circuit The eigenvector used to calculate the common transmission weight is determined from the transmission weight candidate calculation circuit that calculates the side eigenvector and the eigenvalue and outputs to the common transmission weight calculation circuit, and the eigenvector for each communication partner input from the transmission weight candidate calculation circuit. When the selected eigenvector is used for another communication partner Estimate the received signal at the other party, weight the eigenvectors so that the received power at all the other party is almost equal, add together, determine the transmission weight, and output to the transmission signal conversion circuit. And a common transmission weight calculation circuit that outputs a modulation method applied to the modulation circuit and the data division circuit.

  According to a thirteenth aspect of the present invention, in the radio communication apparatus according to the eleventh aspect, the transmission weight determination block estimates a channel response matrix for the communication partner from a signal input from the radio unit, and transmits the communication partner and the transmission signal. Is determined, the channel response acquisition circuit that outputs the channel response matrix of the communication partner to be transmitted to the transmission weight candidate calculation circuit, and the channel response matrix input from the channel information acquisition circuit or the orthogonal spatial channel calculation circuit Based on the input orthogonal spatial channel response matrix, the transmission side eigenvector and eigenvalue obtained by singular value decomposition are calculated and output to the common transmission weight calculation circuit, and the transmission weight candidate calculation circuit is input. Used to determine the common transmission weight from the eigenvectors for each communication partner Determine the presence vector, calculate the inner product value of the selected eigenvector and the eigenvector of the channel response matrix of the other communication partner, and the signal of the other communication partner when the eigenvector selected by the other communication partner is used as the transmission weight In consideration of leakage, weights are added to the eigenvectors so that the reception powers at all communication partners are substantially equal, and the transmission weights are determined and output to the transmission signal conversion circuit and the orthogonal spatial channel arithmetic circuit, Reception side when using transmission weight from common transmission weight calculation circuit that outputs modulation method applied to each communication series to modulation circuit and data division circuit, input transmission weight, and channel response matrix of each communication partner The orthogonal space that calculates the orthogonal spatial channel response matrix orthogonal to the reception beam of the device and outputs it to the transmission weight candidate calculation circuit And Yaneru arithmetic circuit, a wireless communication device characterized by comprising a.

  According to a fourteenth aspect of the present invention, in the wireless communication apparatus according to the eleventh aspect, the transmission weight determination block estimates a channel response matrix for the communication partner from the signal input from the wireless unit, and the communication partner and the transmission signal are determined. Then, a communication partner grouping circuit for grouping communication partners that transmit the same information as the same group, a channel information acquisition circuit that outputs a channel response matrix of the communication partner performing the transmission to the orthogonal spatial channel arithmetic circuit, A channel response matrix corresponding to a communication partner that does not belong to the kth group and whose transmission weight is not determined, with respect to a channel response matrix of a communication partner that belongs to the kth group that determines the input transmission weight; The k-th group first interference space basis vector calculated from the transmission weight input from the transmission weight calculation circuit. And an orthogonal spatial channel response matrix inputted from the orthogonal spatial channel computation circuit, and an orthogonal spatial channel computation circuit for computing the first orthogonal spatial channel response matrix of the k-th group orthogonal to each other and outputting them to the transmission weight candidate computation circuit Based on the transmission side eigenvector and eigenvalue obtained by singular value decomposition, from the transmission weight candidate calculation circuit that outputs to the common transmission weight calculation circuit, and the eigenvector for each communication partner input from the transmission weight candidate calculation circuit, When the eigenvector used to calculate the common transmission weight is determined, the inner product value of the selected eigenvector and the eigenvector of the channel response matrix of the other communication partner is calculated, and the eigenvector selected by a certain communication partner is used as the transmission weight In consideration of signal leakage to other communication partners, all communication partners The eigenvectors are weighted and added together to determine the transmission weight, and output to the transmission signal conversion circuit and the orthogonal spatial channel arithmetic circuit so that the received power is almost equal, and the modulation scheme applied to each communication sequence is modulated. A wireless communication apparatus comprising a circuit and a common transmission weight calculation circuit for outputting to a data dividing circuit.

  According to a fifteenth aspect of the present invention, in the wireless communication apparatus according to the eleventh to fourteenth aspects, the transmission weight determination block is configured to perform orthogonal spatial channel calculation from transmission weights determined in a transmission weight calculation circuit or a common transmission weight calculation circuit In the circuit, a process of obtaining a channel response matrix or an orthogonal spatial channel response matrix orthogonal to the reception beam of the reception side apparatus when using this transmission weight and determining the transmission weight again via the transmission weight candidate calculation circuit. Transmission weight calculation circuit or common transmission weight calculation circuit, orthogonal space channel calculation circuit, transmission weight candidate calculation circuit capable of calculating transmission weights for a common communication partner for any number of communication sequences by repeating an arbitrary number of times A wireless communication apparatus comprising:

  According to a sixteenth aspect of the present invention, in the wireless communication device according to any one of the eleventh to fourteenth aspects, the transmission weight determination block uses the input eigenvector as a transmission weight when there is one communication partner belonging to the group. A wireless communication apparatus including a weight calculation circuit.

  According to a seventeenth aspect of the present invention, in the wireless communication apparatus according to any one of the eleventh to fourteenth aspects, the transmission weight determination block is used to obtain a common transmission weight from the eigenvector for each communication partner input from the transmission weight candidate calculation circuit. A wireless communication apparatus comprising a transmission weight calculation circuit or a common transmission weight calculation circuit that selects a first eigenvector when determining an eigenvector.

  The present invention according to claim 18 is the wireless communication apparatus according to any one of claims 11 to 14, wherein the transmission weight determination block is used to obtain a common transmission weight from an eigenvector for each communication partner input from the transmission weight candidate calculation circuit. The wireless communication apparatus includes a transmission weight calculation circuit or a common transmission weight calculation circuit that selects an eigenvector that takes a value close to an eigenvalue corresponding to the eigenvector when determining the eigenvector.

  According to the present invention, when the same information is transmitted to a plurality of communication partner stations, it is possible to determine a common transmission weight that achieves close transmission quality at each communication partner. By controlling in this way, it is possible to avoid transmitting signals in extra space, and when used in combination with other directivity control methods, the advantage of greatly reducing the amount of freedom of the transmission antenna There is. It is also possible to group several communication partners that transmit common information and perform transmission to each group simultaneously. Also in this case, the degree of freedom of the transmission antenna can be used more effectively than in the case where a transmission beam is formed independently for each communication partner.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
FIG. 1 shows a configuration example of a transmission unit in the first embodiment of the present invention. In Figure 1, 100 is data dividing circuit, 101-1 to 101-L is the modulation circuit, 102 transmitting signal conversion circuit, 103-1 to _{103-M T} wireless unit, 104-1 to _{104-M T} antenna 105 is a channel information acquisition circuit, 106 is a transmission weight candidate calculation circuit, and 107 is a common transmission weight calculation circuit. Reference numeral 110 denotes a transmission weight determination block. The transmission weight determination block 110 includes a channel information acquisition circuit 105, a transmission weight candidate calculation circuit 106, and a common transmission weight calculation circuit 107.

M _{T is} the number of antenna elements of the transmitting device, M _{R is} the number of all receiving antenna elements of all communicating parties that are communicating simultaneously, and M _R (k) is the number of receiving elements of the k-th communicating party. Let L be the number of communication sequences to be performed. As in the prior art, the antenna 104-1 to _{104-M T} and the radio unit 103-1 to _{103-M T} is capable of transmitting and receiving radio signals, the radio unit 103-1～103- based on the converted received signal in M _T, the channel between the channel information obtaining circuit 105, a receiving antenna or reception beams, each antenna 104-1 to 104-M _T and a plurality of communication partner of the transmission unit A response matrix can be estimated. Although this method obtains the channel response matrix is not specified here, the feedback included in the estimate based on whether or received signal information obtained when performing the reception of the known signal in the antenna 104-1 to 104-M _T Information on the channel response matrix for each communication partner is acquired based on the information included in the information.

  When the communication partner and the data to be transmitted are determined, the channel information acquisition circuit 105 outputs the channel response matrix of the corresponding communication partner to the transmission weight candidate calculation circuit 106. In the transmission weight candidate calculation circuit 106, the input channel response matrix is used, and the transmission weight candidate and channel response matrix obtained by linear calculation are output to the common transmission weight calculation circuit 107.

  The common transmission weight calculation circuit 107 uses at least one of the input transmission weight candidates, determines a common transmission weight obtained by performing linear calculation on the candidates, and encodes a modulation scheme and error correction from the expected transmission quality. The transmission mode including the rate is determined, and the information is output to the data division circuit 100, the modulation circuits 101-1 to 101-L, and the transmission signal conversion circuit 102.

Transmission data is divided into L signal series in data division circuit 100 and input to modulation circuits 101-1 to 101-L. Here, a preamble signal or the like for MIMO channel estimation is added and modulated, and then these signals are input to the transmission signal conversion circuit 102. Here, transmission data is multiplied by a transmission weight, is input to the radio unit 103-1 to _{103-M T,} is transmitted as a radio signal through the antenna 104-1 to _{104-M T.}

An example of the control method of the first embodiment of the present invention shown in FIG. 1 is shown below. Here, the same signal sequence is transmitted to two communication partners. The number of transmitting elements is M _T , and the number of receiving antenna elements of the kth communication partner is M _R (k).

First, the transmission weight candidate calculation circuit 106 performs singular value decomposition on the input channel response matrices H ₁ and H ₂ as follows,
H _k = U _k D _k V _k ^H
Eigenvector V _k obtained by singular decomposition
V _k = (v _{k, 1} , v _{k, 2} ,..., V _{k, M (k)} )
Then, the eigenvalues λ _{k, 1} , λ _{k, 2} ,..., Λ _{k, M (k)} are calculated and output to the common transmission weight calculation circuit 107.

M (k) is the number of people transmitting element number _{M T} small receiving antenna element number _M R (k). The eigenvalue is the diagonal component of D _k ,
λ _{k, 1} > λ _{k, 2} >...> λ _{k, M (k)}
And v _{k, 1} , v _{k, 2} ,..., v _{k, M (k)} correspond to these eigenvalues. The transmission weight candidate calculation circuit 106 performs a common transmission weight calculation on the transmission weight candidate, V _k , and the expected transmission quality, λ _{k, 1} , λ _{k, 2} ,..., Λ _{k, M (k).} Output to the circuit 107.

  In the common transmission weight calculation circuit 107, the following calculation is performed between the input eigenvectors of the communication partner.

chi _{kl, ij} denotes the i th eigenvector of the k th communication partner, the inner product of the l th j th eigenvector of the communication _partner, α _kl, ijj the chi _kl, amplitude values _ij, theta _{kl, ij} Represents the phase angle of χ _{kl, ij} . χ _{kl, ij} = χ _{lk, ji}

When the i-th eigenvector v _{k, i} of the _k-th communication partner is used for the l-th communication partner, the total power P _{l, k, i} received at the l-th communication partner can be expressed as follows: it can.

  First, consider forming one communication sequence common to the first and second communication partners according to the present invention. It is desirable that a common communication line has the same communication quality for all communication partners that communicate using a common beam. The present invention is characterized in that the communication partner k-th and l-th eigenvectors are used together.

If the first eigenvector is used, a common transmission weight capable of transmitting a large amount of information to both can be determined. At this time, it is assumed that the first eigenvalue of the second communication partner is smaller than the first eigenvalue of the first communication partner. At this time, first, the received power of the first communication partner when using the first eigenvector of the second communication partner is estimated from Equation 4. At this time, if the reception power of the first communication partner is equal to the first eigenvalue of the second communication partner, this is set as a transmission weight.
Hereinafter, a common weight calculation method for realizing the maximum transmission capacity when the received power of the first communication partner is equal to or less than the first eigenvalue of the second communication partner will be described.

Assume that the ratio of the first eigenvector of the first communication partner is η ₁ , the ratio of the first eigenvector of the second communication partner is η ₂ , and the phase rotation angle given to the second eigenvector is φ. | Η ₁ v _1,1 + η ₂ v _2,1 | = 1. Then, by common beam expected in the first communication partner, the received power gamma _C1,1 of the first communication partner, the received power gamma _c1,2 of the second communication partner, represented as follows be able to.

In order to maximize the received power, it is only necessary to set φ = −θ ₁₂ , _11, and the distribution ratio η ₂ / η ₁ for realizing Γ _c1,2 = Γ _c1,2 by the common beam is as follows. The solution can be obtained from the following equation and | η ₁ v _1,1 + η ₂ v _2,1 | = 1, 1 ≧ η ₁ ≧ 0, 1 ≧ η ₂ ≧ 0.

Further, the transmission weight w _c1 for forming the common beam can be expressed as follows.

Next, consider a case where the received power of the first communication partner is equal to or greater than the first eigenvalue of the second communication partner. In this case, when there is no other communication stream that needs to be transmitted to the first communication partner, the first eigenvector of the second communication partner may be used as the transmission weight. However, when it is necessary to transmit other information to the first communication partner, the common weight has used excessive space resources, and control is performed so as to reduce the reception power at the first communication partner. There is a need. In this case, the additional eigenvector v _{1, M (1) +1} orthogonal to the transmission side eigenvector v _{1,1 to} v _{1 , M (1) of the first} communication partner is newly calculated. For example, the additional eigenvector is obtained by subtracting the non-orthogonal component from the inner product of v _1,1 to v _{1 , M (1)} from the first eigenvector of the second communication partner and obtaining the second first eigenvector. If it is determined to have a high correlation value with the eigenvector, the quality degradation of the second communication partner can be reduced.
The received power of the first and second communication partners is represented by the superposition of the additional eigenvector of the first communication partner and the first eigenvector of the second communication partner as follows.

The distribution ratio η ₂ / η ₁ for realizing Γ _c1,2 = Γ _c1,2 by the common beam can be obtained from the quadratic equation as in Equation 6, and the common transmission weight is expressed as follows: Can do.

Even when the number of communication partners is larger than 2, the common weight can be determined in the same manner. However, if there are M _c communication partners, in this case, the phase rotation angle φ ₁ to _φ1MC cannot be determined uniquely. The received powers Γ _c1,1 , Γ _c1,2 ... _{ΓΓ1 , Mc} can be expressed as follows.

  FIG. 2 shows a transmission flow in the first embodiment of the present invention. In FIG. 2, before performing communication, a channel response matrix corresponding to a communication partner performing transmission is estimated in advance (step S101).

When communication partners are determined (step S102) and transmission data is determined (step S103), eigenvectors and eigenvalues are calculated for each communication partner using the channel response matrix of the corresponding Mc communication partners (step S103). S104) For each communication partner, it is determined which eigenvector is used to determine the common transmission weight (step S105). Here the k th t _k th determined for the communication partner of eigenvectors, inner product value with all eigenvectors in the communication partner other than k-th is calculated (step S106), the inner product values and eigenvalues of the determined vectors between Then, a common transmission weight is calculated by adding the eigenvectors, and a transmission mode including a modulation scheme and a coding rate is determined (step S107).

The data to be transmitted is subjected to modulation processing and addition of a known signal (step S108), and the processing in the signal conversion circuit is performed in symbol units. For example, the signal vector at the symbol for the kth communication partner is S _k, and k If the transmission weight for the second communication partner is W _k , a signal conversion process for performing a signal conversion process of S _k → W _k · S _k is performed (step S109). In this way, the processed baseband signal is converted into an RF signal by a radio unit corresponding to each antenna and transmitted (step S110).

(Second Embodiment)
FIG. 3 shows a configuration example of the transmission weight determination block 110 in the second exemplary embodiment of the present invention. In FIG. 3, 205 is a channel information acquisition circuit, 206 is a transmission weight candidate calculation circuit, 207 is a common transmission weight calculation circuit, and 208 is an orthogonal spatial channel calculation circuit.

  When the communication partner and the data to be transmitted are determined, the channel response matrix of the corresponding communication partner is output from the channel information acquisition circuit 205 to the transmission weight candidate calculation circuit 206 and the orthogonal spatial channel calculation circuit 208. The transmission weight candidate calculation circuit 206 uses the input channel response matrix and outputs the transmission weight candidate and channel response matrix obtained by linear calculation to the common transmission weight calculation circuit 207.

  The common transmission weight calculation circuit 207 uses at least one of the input transmission weight candidates, determines a common transmission weight obtained by performing linear calculation on the candidates, and determines the modulation scheme and error correction code from the expected transmission quality. The transmission mode including the conversion rate is determined, and these pieces of information are output to the data division circuit 100, the modulation circuits 101-1 to 101-L, the transmission signal conversion circuit 102, and the orthogonal spatial channel arithmetic circuit 208.

  The orthogonal spatial channel calculation circuit 208 calculates an orthogonal spatial channel response matrix for each communication partner from a component orthogonal to the reception beam of the communication partner when a common transmission weight is used for the input channel response matrix, The data is output to the transmission weight candidate calculation circuit 206.

An example of the control method according to the second embodiment of the present invention will be described below. In the second embodiment of the present invention, it is assumed that a plurality of signal sequences are transmitted by a common beam, and it is considered that the same signal sequence is transmitted to Mc communication partners. The number of transmitting elements is M _T , and the number of receiving antenna elements of the kth communication partner is M _R (k).

First, the transmission weight candidate calculation circuit 206 outputs the transmission weight candidates and channel response matrix obtained by linear calculation to the common transmission weight calculation circuit 207 using the input Mc channel response matrices. The common transmission weight calculation circuit 207 calculates the first common transmission weight w _c1 (M _T × 1 vector) and outputs it to the orthogonal spatial channel calculation circuit 208, as in the first embodiment.

The orthogonal spatial channel arithmetic circuit 208 estimates the reception weight used by the communication partner when the common weight is used, and calculates the orthogonal spatial channel response matrixes H ′ _{1 to} H ′ _Mc so that the transmission signal does not interfere with this reception weight. Calculate. For example, the i th row vector of the k th channel response matrix H _k is h _{k, i} (1 × M _T vector), and the i th row vector of the k th orthogonal spatial channel response matrix H ′ _k is h ′. _k, and i (1 × _{M T} vector), the interference spatial vector for the k-th communication partner obtained by multiplying the common weight to the k-th channel response matrix w _'k = and _w ^cl _H H _^k H H ^k Then, the kth orthogonal channel response matrix can be calculated as follows.

Based on the orthogonal spatial channel response matrixes H ′ _{1 to} H ′ _Mc obtained in this way, the second common transmission weight w is obtained using the orthogonal channel response matrix in the same manner as the method described in the first embodiment. _c2 can be calculated.

Further, when transmitting the third communication sequence by the common beam, the second common transmission weight w _c2 obtained as described above is output to the orthogonal spatial channel arithmetic circuit 208, and the second common weight is obtained. When used, a second orthogonal spatial channel response matrix H ″ _{1 to} H ″ _Mc , which is a matrix orthogonal to the reception weight formed by the communication partner, is calculated. When the interference space vector for the k-th communication partner obtained by multiplying the k-th channel response matrix by the common weight is w ″ _k = w _c2 ^H H ′ _k ^H H ′ _k , attention is paid to the k-th communication partner. Then, it can be calculated as follows.

By obtaining the orthogonal spatial channel response matrix in this way, an arbitrary number of common transmission weights of min (M _R (k)) or less can be determined.

  FIG. 4 shows a transmission flow in the second embodiment of the present invention. In FIG. 4, before performing communication, a channel response matrix corresponding to a communication partner performing transmission is estimated in advance (step S201).

When a communication partner is determined (step S202) and transmission data is determined (step S203), an eigenvector is assigned to each communication partner using the channel response matrix or orthogonal spatial channel response matrix of the corresponding Mc communication partners. The eigenvalue is calculated (step S204), and for each communication partner, it is determined which eigenvector is used to determine the common transmission weight (step S205). Here the k th t _k th determined for the communication partner of eigenvectors, inner product value with all eigenvectors in the communication partner other than k-th is calculated (step S206), the inner product values and eigenvalues of the determined vectors between Then, a transmission mode including the common transmission weight, the modulation scheme, and the coding rate is determined (step S207).

  At this time, it is determined whether or not all transmission weights of the communication series to be transmitted are determined (step S208). If not determined, estimate the reception weight used by the communication partner when the transmission weight is used for the channel response matrix or orthogonal spatial channel response matrix for which the eigenvector is calculated from the obtained transmission weight, and this reception beam The orthogonal spatial channel response matrix orthogonal to is calculated (step S209), and the transmission weight determination flow is repeated again.

If determined, the data to be transmitted is divided into L sequences based on the transmission mode determined for each communication sequence (step S210), modulation processing and addition of a known signal are performed (step S211), and signal conversion is performed. The processing in the circuit is performed on a symbol-by-symbol basis. For example, if the signal vector at the symbol for the kth communication partner is S _k and the transmission weight for the _kth communication partner is W _k , then S _k → W _k · S _k The signal conversion process for performing the signal conversion process is performed (step S212). Thus, the processed baseband signal is converted into an RF signal by a radio unit corresponding to each antenna and transmitted (step S213).

(Third embodiment)
FIG. 5 shows a configuration example of the transmission weight determination block 110 in the third embodiment of the present invention. In FIG. 5, 305 is a channel information acquisition circuit, 306 is a transmission weight candidate calculation circuit, 307 is a transmission weight calculation circuit, 308 is an orthogonal spatial channel calculation circuit, and 309 is a communication partner grouping circuit.

  In the third embodiment of the present invention, it is assumed that communication partners that perform transmission using a common beam are grouped in advance, a common beam is determined for each determined group, and transmission is performed.

When the communication partner and the data to be transmitted are determined, the communication partner grouping circuit 309 divides the communication partner using the common communication sequence into M _g (> 1) groups, and is requested for the group information and the communication sequence. Is output to the channel information acquisition circuit 305.

  The channel information acquisition circuit 305 outputs the channel response matrix of the corresponding communication partner to the orthogonal spatial channel calculation circuit 308 from the input information.

  In the orthogonal spatial channel calculation circuit 308, when first obtaining the transmission weight of the first group, at least a part of the channel response matrix other than the first group is defined as an interference spatial channel response matrix, and for these interference spaces, A first group channel response matrix having orthogonal components and a first group first orthogonal spatial channel response matrix are obtained and output to the transmission weight candidate calculation circuit 306.

  The transmission weight candidate calculation circuit 306 outputs the transmission weight candidate and channel response matrix obtained by linear calculation to the transmission weight calculation circuit 307 using the input first group first orthogonal spatial channel response matrix.

  The transmission weight calculation circuit 307 uses at least one of the input transmission weight candidates, determines the first transmission weight of the first group obtained by performing linear calculation on the candidates, and determines the modulation method from the expected transmission quality. And the transmission mode including the error correction coding rate and the like are output to the data division circuit 100, the modulation circuits 101-1 to 101-L, the transmission signal conversion circuit 102, and the orthogonal spatial channel arithmetic circuit 308. .

  In the orthogonal spatial channel calculation circuit 308, when the second transmission weight of the first group is subsequently determined, the first group of the first group of the first orthogonal spatial channel response matrix of the first group is determined. When the transmission weight is used, the second orthogonal spatial channel response matrix of the first group, which is a component orthogonal to the reception beam formed by the communication partner, is calculated and output to the transmission weight candidate calculation circuit 306 again. The second transmission weight can be determined in the same manner as the first transmission weight of one group. Further, by repeating such processing an arbitrary number of times, it is possible to determine the transmission weight of an arbitrary number of communication sequences in the first group.

Next, a transmission weight common to the second group is determined. In the orthogonal spatial channels arithmetic circuit 308, do not belong to the second group, and at least a portion of the channel response matrix to the communication counterpart belonging to the 3～M _g th group, with a transmission weight to the first group A vector corresponding to the received beam formed by the communication partner is defined as an interference spatial channel response matrix, and a second group of channel response matrices having a component orthogonal to the interference space, the second group first An orthogonal spatial channel response matrix is obtained and output to the transmission weight candidate calculation circuit.

  In the transmission weight candidate calculation circuit 306, the input second group first orthogonal spatial channel response matrix is used, and the transmission weight candidate and channel response matrix obtained by linear calculation are output to the transmission weight calculation circuit 307.

  The transmission weight calculation circuit 307 uses at least one of the input transmission weight candidates, determines the first transmission weight of the second group obtained by performing linear calculation on them, and determines the modulation scheme and the like from the expected transmission quality. A transmission mode including an error correction coding rate and the like is determined, and these pieces of information are output to the data division circuit 100, the modulation circuits 101-1 to 101-L, the transmission signal conversion circuit 102, and the orthogonal spatial channel arithmetic circuit 308.

  In the orthogonal spatial channel arithmetic circuit 308, when the second transmission weight of the second group is subsequently determined, the first of the second group of the first orthogonal spatial channel response matrix of the second group is determined. When the transmission weight is used, the second orthogonal spatial channel response matrix of the second group, which is a component orthogonal to the reception beam formed by the communication partner, is calculated and output to the transmission weight candidate calculation circuit 306 again. Similar to the first transmission weight of the second group, the second transmission weight of the second group can be determined. Further, by repeating such processing an arbitrary number of times, it is possible to determine the transmission weight of an arbitrary number of communication sequences in the first group.

  By performing the above calculation on each group, transmission weights for all groups can be determined. The communication partner may belong to a plurality of groups, and the group may be composed of one communication partner. Further, the order of determining the transmission weight can be arbitrarily changed.

  An example of the control method according to the third embodiment of the present invention will be described below. Here, it is assumed that transmission is performed to the first to fifth communication partners, the first to third, third to fourth communication partners need common information, and the fourth and fifth communications are further performed. Assume that the other party needs an independent signal sequence. First, the grouping circuit includes the first to third communication partners as the first group, the third to fourth communication partners as the second group, the fourth communication partner as the third group, and the fifth communication. The opponent is determined to be the fourth group.

First, the channel information acquisition circuit 305 outputs the channel response matrices of the five communication partners to the orthogonal spatial channel calculation circuit 308. The orthogonal space channel calculation circuit 308 first calculates an interference space basis vector from the fourth and fifth communication partners other than the first group. The first interference space matrix is represented as [H ₍₄₎ ^T , H ₍₅₎ ^T ] ^T ((M _R (4) + M _R (5)) × M _T matrix)
If a signal is transmitted to a space constituted by this matrix, it becomes an interference signal to communication partners of other groups.

Interference space matrix [H ₍₄₎ ^T , H ₍₅₎ ^T ] By using the orthogonalization method for the row vector of ^T , the first interference space basis vector can be determined. The number of interference space basis vectors does not need to be (M _R (4) + M _R (5)). For example, by assuming reception weights for the fourth and fifth communication partners, one or more M _R ( 4) + M _R (5) M _I (1) interference space basis vectors which are the following numbers can be selected.

In order to obtain such an interference basis vector, the interference space matrix [H ₍₄₎ ^T , H ^{₍₅₎ T]} Select _M I (1) number of row vectors from ^T, the configuration and matrix as _{G (1) (M I (} 1) × M T matrix), the a-th row vector g _{1 and a} , the first interference space basis vectors e _1,1 , e ₁ , ₂ ,..., E _{1, MI (1)} are as follows. It can be obtained as follows.

E ₍₁₎ = [e _1,1 ^T , e ₁ , ₂ ^T , ... e _{1, MI (1)} ^T ] ^T
Is the first interference space basis vector group for the communication partner of the first group.

Further, as this first interference space basis vector, singular value decomposition is performed on channel response matrices H ₍₄₎ and H ₍₅₎ corresponding to communication partners other than the communication partner of the first group,
H ₍₄₎ = U ₍₄₎ D ₍₄₎ V ₍₄₎ ^H ,
H ₍₅₎ = U ₍₅₎ D ₍₅₎ V ₍₅₎ ^H
Transmitter eigenvector V in ₍₄₎
V ₍₄₎ = (v _4,1 ,..., V _{4, MR (4)} ),
V ₍₅₎ = (v _5,1 ,..., V _{5, MR (5)} )
A vector obtained by using the orthogonalization method for the conjugate complex vector can be selected as E ₍₁₎ .

Next, first orthogonal spatial channel response matrices H ′ _{(1) to} H ′ ₍₃₎ for the first to third communication partners are obtained using the first interference interference basis vector. The first orthogonal spatial channel response matrices H ′ _{(1) to} H ′ ₍₃₎ are matrices composed of vectors that are completely orthogonal to all or part of the channels of the first to third communication partners. .

If the transmission weight is determined in the first orthogonal space, it is possible to reduce interference with other communication sequences for the fourth to fifth communication partners. The first orthogonal spatial channel response matrix H ′ _{(1) to} H ′ ₍₃₎ is the channel response matrix H ( ₁ ).
H ( ₁ ) = [h _1,1 ^T , h _1,2 ^T ,..., H _{1, MR (1)} ^T ] ^T ,
^{_{H (2) = [h 2,1}} T, h 2,2 T, ···, h 2, MR (2) T ] ^T ,
H ( ₃ ) = [h _3,1 ^T , h _3,2 ^T ,..., H _{3, MR (3)} ^T ] ^T
And interference space basis vector group E ₍₁₎
E ₍₁₎ = [e _1,1 ^T , e ₁ , ₂ ^T , ..., e _{1, MI (1)} ^T ] ^T
Can be obtained as follows.

The first orthogonal spatial channel response matrices H ′ _{(1) to} H ′ ₍₃₎ are output to the transmission weight candidate calculation circuit 306, and these channel matrices are subjected to singular value decomposition.
H ′ _k = U ′ _k D ′ _k V ′ _k ^H (k = 1, 2, 3)
Eigenvector V ′ _k obtained by singular decomposition
V ′ _k = (v ′ _{k, 1} , v ′ _{k, 2} ,..., V ′ _{k, M (k)} )
And eigenvalues λ ′ _{k, 1} , λ ′ _{k, 2} ,..., Λ ′ _{k, M (k)}
Is output to the transmission weight calculation circuit 307.

M (k) is the number of smaller transmission element number _{M T} and the receiving antenna element number _M R (k). The eigenvalue is the diagonal component of D _k ,
λ ′ _{k, 1} > λ ′ _{k, 2} >...> λ ′ _{k, M (k)}
, And v ′ _{k, 1} , v ′ _{k, 2} ,..., V ′ _{k, M (k)} correspond to these eigenvalues.

The transmission weight candidate calculation circuit 306 transmits the transmission weight candidate, V ′ _k , and the expected transmission quality, λ ′ _{k, 1} , λ ′ _{k, 2} ,..., Λ ′ _{k, M (k)} . The data is output to the weight calculation circuit 307. (K = 1, 2, 3)

  In the transmission weight calculation circuit 307, the following calculation is performed between the input eigenvectors of the communication partner.

χ ^(1,1) _{kl, ij} represents the inner product of the i-th eigenvector of the k-th communication partner in the first group and the j-th eigenvector of the l-th communication partner, and α ^{(1,1 )} _{Kl, ij} represents the amplitude value of χ ^(1,1) _{kl, ij} , and θ ^(1,1) _{kl, ij} represents the phase angle of χ ^(1,1) _{kl, ij} .
χ ^(1,1) _{kl, ij} = χ ^(1,1) _{lk, ji}
It becomes.

Hereinafter, as in the first embodiment, an arbitrary number of common transmission weights can be determined for the group 1. Here, it is assumed that the number of transmission weights determined for the group 1 is 2, and these common weights are w _1c1 and w _1c2 .

  When the transmission weight to group 1 is determined, the transmission weight to group 2 is then determined. For this purpose, a second orthogonal spatial channel response matrix corresponding to the second group is calculated.

In the orthogonal spatial channel arithmetic circuit 308, first, the channel response matrix of the fifth communication partner that has not yet determined the transmission weight other than the second group and the first group that has already been determined. The interference space basis vector is calculated from the transmission weights w _1c1 and w _{1c2 of} .

The reception weights formed by the first to third communication partners with respect to the common transmission weight to the first group are [H ₍₁₎ W _1c1 , H ₍₂₎ W _1c1 , H ₍₃₎ W _1c1 , H ' ₍₁₎ W _1c2 , H' ₍₂₎ W _1c2 , H ' ₍₃₎ W _1c2 ] ^* * Represents a complex conjugate.
Using the complex conjugate matrix of the reception weight, the second interference space matrix [(w _1c1 ^H H ₍₁₎ ^H H ₍₁₎ ) ^T , (w _1c1 ^H H ₍₂₎ ^H H ₍₂₎ ) ^T , (W _1c1 ^H H ₍₃₎ ^H H ₍₃₎ ) ^T , (w _1c2 ^H H ′ ₍₁₎ ^H H ′ ₍₁₎ ) ^T , (w _1c2 ^H H ′ ₍₂₎ ^H H ′ ₍₂₎ ) ^T , (w _1c2 ^H H ′ ₍₃₎ ^H H ′ ₍₃₎ ) ^T , H ₍₅₎ ^T ] ^T ((6 + M _R (5)) × M _T matrix) When a signal is transmitted to space, it becomes an interference signal to communication partners of other groups.

By using the orthogonalization method for the row vector of the second interference space matrix, the second interference space basis vector can be determined. The number of interference space basis vectors need not be (2 + M _R (5)), and M _I (2) interference space basis vectors, which is a number between 1 and 2 + M _R (5), can be selected. For example, assuming a reception weight W _f (M _T (5) × M ′ _T (5)) at the communication partner, the second interference space matrix is expressed as [(w _1c1 ^H H ₍₁₎ ^H H ₍₁₎ ) ^T , (w _1c1 ^H H ₍₂₎ ^H H ₍₂₎ ) ^T , (w _1c1 ^H H ₍₃₎ ^H H ₍₃₎ ) ^T , (w _1c2 ^H H ′ ₍₁₎ ^H H ′ ₍₁₎ ) ^T , (w _1c2 ^H H ′ ₍₂₎ ^H H ′ ₍₂₎ ) ^T , (w _{1c 2} ^H H ′ ₍₃₎ ^H H ′ ₍₃₎ ) ^T , (W _f ^H H ₍₅₎ ) ^T ] It can be used as ^T. M ′ _T (5) ≦ M _T (5). Alternatively, M _I (2) row vectors can be selected from the second interference space matrix to form G ₍₂₎ (M _I (2) × M _T matrix). M _I (2) ≦ (6 + M _R (5)). At this time, there may be an interference signal on the receiving side, but it can be removed by the decoding means of the communication partner. When the a-th row vector of the reception G ₍₂₎ is g _{2, a} , the second interference space basis vectors e _2,1 , e _2,2 ..., E _{2, MI (2)} are Can be asking.

E ₍₂₎ = [e _2,1 ^T , e _2,2 ^T ,..., E _{2, MI (2)} ^T ] ^T is the second interference space basis vector group for the communication partner of the second group is there.

Next, using this first interference interference basis vector, second orthogonal spatial channel response matrices H ″ ₍₃₎ and H ″ ₍₄₎ for the third to fourth communication partners are obtained. This second orthogonal spatial channel response matrix H ″ ₍₃₎ , H ″ ₍₄₎ is completely the communication sequence to the first group and all or part of the channel of the fifth communication partner. It is a matrix composed of orthogonal vectors. By determining the transmission weight in the first orthogonal space, it is possible to reduce the interference of the first group of communication sequences and the fifth communication partner with other communication sequences.

The second orthogonal spatial channel response matrix H ″ ₍₃₎ , H ″ ₍₄₎ is obtained by the channel response matrix H ( ₃ ) = [h _3,1 ^T , h _3,2 ^T ,..., H _{3 , MR (3)} ^T ] ^T ,
H ( ₄ ) = [h _4,1 ^T , h _4,2 ^T ,..., H _{4, MR (4)} ^T ] ^T
And interference space basis vector group E ₍₂₎
E ₍₂₎ = [e _1,1 ^T , e ₁ , ₂ ^T , ... e1 _{, MI (2)} ^T ] ^T
Can be obtained as follows.

An eigenvector and an eigenvalue are calculated from the second orthogonal spatial channel response matrix thus obtained, and an arbitrary number of common transmission weights can be determined as described in the first embodiment. Here, it is assumed that there is one communication series for the second group and the transmission weight w _2c1 for the second group is determined.

Next, the transmission weight to the third group is determined. For this purpose, a third orthogonal spatial channel response matrix corresponding to the third group is calculated. In the orthogonal spatial channel arithmetic circuit 308, the channel response matrix of the fifth communication partner, which is a communication partner that has not yet determined the transmission weight, other than the third group, and the first group that has already been determined. transmitting weight _{w 1c1, w 1c2} and calculates the interference spatial basis vectors from the transmit weights _{w 2c1} of the second group.

The third interference space matrix [(w _1c1 ^H H ₍₁₎ ^H H ₍₁₎ ) ^T , (w _1c1 ^H H ₍₂₎ ^H H ₍₂₎ ) ^T , (w _1c1 ^H H ₍₃₎ ^H H _{( ^{3)) T, (w 1c2}} H H '(1) H H' (1)) T, (w 1c2 H H '(2) H H' (2)) T, (w 1c2 H H '(3) ^H H ′ ₍₃₎ ) ^T , (w _2c1 ^H H ″ ₍₃₎ ^H H ″ ₍₃₎ ) ^T , (w _2c1 ^H H ″ ₍₄₎ ^H H ″ ₍₄₎ ) ^T , H _{(5) When} ^T ] ^T ((8 + M _R (5)) × M _T matrix) is defined, when a signal is transmitted to a space configured by this matrix, it becomes an interference signal to communication partners of other groups.

The third interference space matrix [(w _1c1 ^H H ₍₁₎ ^H H ₍₁₎ ) ^T , (w _1c1 ^H H ₍₂₎ ^H H ₍₂₎ ) ^T , (w _1c1 ^H H ₍₃₎ ^H H _{( ^{3)) T, (w 1c2}} H H '(1) H H' (1)) T, (w 1c2 H H '(2) H H' (2)) T, (w 1c2 H H '(3) ^H H ′ ₍₃₎ ) ^T , (w _2c1 ^H H ″ ₍₃₎ ^H H ″ ₍₃₎ ) ^T , (w _2c1 ^H H ″ ₍₄₎ ^H H ″ ₍₄₎ ) ^T , H ₍₅₎ ^T ] By using the orthogonalization method for the row vector of ^T , the third interference space basis vector can be determined.

The number of interference space basis vectors does not need to be (3 + M _R (5)), and M _I (3) interference space basis vectors, which is a number not less than 1 and not more than 3 + M _R (5), are assigned to the second group. And G ₍₃₎ (M _I (3) × M _T matrix) can be formed. Assuming that the a-th row vector of G ₍₃₎ is g _{3, a} , the third interference space basis vectors e _3,1 , e _3,2 ..., E _{3, MI (3)} are as follows: Can be requested.

E ₍₃₎ = [e _3,1 ^T , e _3,2 ^T , ... e3 _{, MI (3)} ^T ] ^T
Is a third interference space basis vector group for the communication partner of the third group.

The third orthogonal spatial channel response matrix H ′ ″ ₍₄₎ can be calculated from the third interference space basis vector group thus obtained and the channel response matrix H ₍₄₎ . Here, since only the fourth communication partner belongs to the third group, the transmission weight is determined from a vector obtained by a linear operation from the third orthogonal spatial channel response matrix H ′ ″ _(4). it can.

For example, singular value decomposition H ′ ″ ₍₄₎ = U ′ ″ ₍₄₎ D ′ ″ ₍₄₎ V ′ ″ ₍₄₎ ^H
The column vector of the eigenvector V ′ ″ ₍₄₎ obtained from the above can be determined as the transmission weight. Here, it is assumed that the transmission weight w _3c1 to the third group is determined.

Finally, the transmission weight to the fourth group is determined. Here, since there is no communication partner whose transmission weight is not determined except for the fourth group, the fourth interference is set so as not to cause interference in the transmission weight determined for the communication sequence to the first to third groups. Spatial matrix [(w _1c1 ^H H ₍₁₎ ^H H ₍₁₎ ) ^T , (w _1c1 ^H H ₍₂₎ ^H H ₍₂₎ ) ^T , (w _1c1 ^H H ₍₃₎ ^H H ₍₃₎ ) ^T , (W _1c2 ^H H ′ ₍₁₎ ^H H ′ ₍₁₎ ) ^T , (w _1c2 ^H H ′ ₍₂₎ ^H H ′ ₍₂₎ ) ^T , (w _1c2 ^H H ′ ₍₃₎ ^H H ′ _{( 3)} ) ^T , (w _2c1 ^H H ″ ₍₃₎ ^H H ″ ₍₃₎ ) ^T , (w _2c1 ^H H ″ ₍₄₎ ^H H ″ ₍₄₎ ) ^T , (w _3c1 ^H H from '' ^{_'(4) H} H' ^{_"(4)) T] T,} fourth orthogonal space channel response matrix H ''_{'' (5)} calculated, belongs communication partner is one this From the transmission weight can be determined from the vector obtained by linear operation from the fourth orthogonal spatial channel response matrix H ''_{'' (5).}

  Although the present invention has been described so far using the first eigenvector of the channel response matrix or the orthogonal spatial channel response matrix, an arbitrary eigenvector may be used. For example, the transmission weight may be determined as in Equations (5) to (9) using eigenvectors corresponding to the channel response matrix of each communication partner or the eigenvalue of the orthogonal spatial channel response matrix that are close to each other. it can. Alternatively, the second and lower rank eigenvectors can be used according to the required transmission rate.

Here, considering that the common transmission weight is calculated for the Mc communication partners, the tkth eigenvector is used for the _kth communication partner. Then, Formula (8) can be expressed as follows.

Here, Γ _c1,1 , Γ _c1,2 ,..., Γ _{c1, Mc} are set to the same value as much as possible, or min (Γ _{c1, k} ) is minimized, or min (Γ _{c1 , k)} a to the maximum and max a (Γ _{c1, j)} to a minimum, η ₁ ² ~η _Mc ² and _{θ 12,} τ1τ2 ² ~θ _1Mc, the _Tau1tauMc ² can be determined. k refers to 1 to M _C all of the communication partner, j points to the communicating party needs to communicate with another.

  FIG. 6 shows a transmission flow in the third embodiment of the present invention. In FIG. 6, before performing communication, a channel response matrix corresponding to a communication partner performing transmission is estimated in advance (step S301).

  When a communication partner is determined (step S302) and transmission data is determined (step S303), grouping is performed for each communication partner that transmits the same transmission data, and a response matrix for the communication partner is estimated (S133-1). ) Transmission weights are determined in order from the first group (m = 1) (step S305).

An interference space basis vector group is calculated from the channel response matrix of a communication partner that does not belong to the mth group and whose transmission weight is not determined (step S306), and the mth so as to be orthogonal to these interference space basis vectors. An orthogonal spatial channel response matrix of the channel response matrix for communication partners belonging to the group is obtained (step S307). Using the orthogonal spatial channel response matrix of Mc (m) communication partners belonging to the mth group, eigenvectors and eigenvalues are calculated for each communication partner (step S308), and which eigenvector is used for each communication partner. To determine the common transmission weight (step S309). Here the k th t _k th determined for the communication partner of eigenvectors, inner product value with all eigenvectors in the communication partner other than k-th is calculated (step S310), the inner product values and eigenvalues of the determined vectors between Then, a transmission mode composed of the common transmission weight, the modulation scheme, and the coding rate is determined (step S311).

  At this time, it is determined whether all the transmission weights of the communication sequences to be transmitted to the mth group have been determined (step S312). If all transmission weights of the communication sequence to be transmitted to the m-th group have not been determined, the communication partner is determined for the determined transmission weight with respect to the orthogonal spatial channel response matrix in which the eigenvector is calculated from the obtained transmission weight. A second orthogonal spatial channel response matrix composed of components orthogonal to the reception weight to be formed is calculated (step S313), and the transmission weight determination flow is repeated again.

  If all transmission weights of the communication sequence to be transmitted to the mth group have been determined, it is determined whether transmission weights have been determined for all groups (step S314).

  If transmission weights have not been determined for all groups, m is incremented (step S315), the interference space basis vector is calculated for the (m + 1) th group, and transmission weights are similarly determined.

If transmission weights are determined for all groups, the data to be transmitted is divided into L sequences based on the transmission mode determined for each communication sequence (step S316), and modulation processing and addition of known signals are performed. (Step S317) The processing in the signal conversion circuit is performed on a symbol-by-symbol basis. For example, if the signal vector at the symbol for the k-th communication partner is S _k and the transmission weight for the k-th communication partner is W _k , S A signal conversion process for performing a signal conversion process of _k → W _k · S _k is performed (step S318). In this way, the processed baseband signal is converted into an RF signal by the radio unit corresponding to each antenna and transmitted (step S319).

  As described above in detail, according to the embodiment of the present invention, when the same information is transmitted to a plurality of communication partner stations, it is possible to determine a common transmission weight that achieves close transmission quality at each communication partner. . By controlling in this way, it is possible to avoid transmitting signals in extra space, and when used in combination with other directivity control methods, the advantage of greatly reducing the amount of freedom of the transmission antenna There is. It is also possible to group several communication partners that transmit common information and perform transmission to each group simultaneously. Also in this case, the degree of freedom of the transmission antenna can be used more effectively than in the case where a transmission beam is formed independently for each communication partner.

  The present invention uses the same frequency channel, spatially multiplexes and transmits independent signal sequences from a plurality of different transmission antennas, receives signals using a plurality of reception antennas, and obtains a channel response matrix between the transmission and reception antennas. Basically, it can be used for MIMO communication in which data is demodulated on the receiving station side.

FIG. 3 is a diagram illustrating a configuration example of a transmission unit according to the first embodiment of the present invention. It is a figure which shows the transmission flow in the 1st Embodiment of this invention. It is a figure which shows the structural example of the transmission weight determination block in the 2nd Embodiment of this invention. It is a figure which shows the transmission flow in the 2nd Embodiment of this invention. It is a figure which shows the structural example of the transmission weight determination block in the 3rd Embodiment of this invention. It is a figure which shows the transmission flow in the 3rd Embodiment of this invention. It is a figure which shows the structural example of the transmission part in a prior art.

Explanation of symbols

100: Data division circuits 101-1 to 101-L ... Modulation circuit 102 ... Transmission signal conversion circuits 103-1 to 103-M _T ... Radio units 104-1 to 104M _T ... Antenna 105 ... Channel information acquisition circuit 106 ... Transmission weight candidate calculation circuit 107 ... Common transmission weight calculation circuit 110 ... Transmission weight determination block 205 ... Channel information acquisition circuit 206 ... Transmission weight candidate Arithmetic circuit 207 ... Common transmission weight arithmetic circuit 208 ... Orthogonal spatial channel arithmetic circuit 305 ... Channel information acquisition circuit 306 ... Transmission weight candidate arithmetic circuit 307 ... Transmission weight arithmetic circuit 308 ... Orthogonal Spatial channel arithmetic circuit 309 ... Communication partner group division circuit 900 ... Data division circuit

Claims (18)

Equipped with multiple antenna elements, estimate the channel response matrix representing the propagation environment between the antennas of the communication partner, determine the transmission weight and perform transmission weighting on the transmission signal, A wireless communication method for transmitting a transmission signal,
Calculating an eigenvector and an eigenvalue obtained from a transmission side correlation matrix of a channel response matrix corresponding to a communication partner transmitting common data;
Using two or more of the obtained eigenvectors, multiplying each by a correction value, and determining the added vector as a common transmission weight;
A wireless communication method comprising: Equipped with multiple antenna elements, estimate the channel response matrix representing the propagation environment between the antennas of the communication partner, determine the transmission weight and perform transmission weighting on the transmission signal, A wireless communication method for transmitting a transmission signal,
Calculating an eigenvector obtained from a transmission side correlation matrix of a channel response matrix corresponding to a communication partner transmitting common data;
Estimating a received signal received by another communication partner when using an eigenvalue for a communication partner from an inner product value;
Multiplying a selected eigenvector by a correction value so as to receive an equivalent reception signal for each communication partner, adding together, and determining a common transmission weight;
A wireless communication method comprising: Equipped with multiple antenna elements, estimate the channel response matrix representing the propagation environment between the antennas of the communication partner, determine the transmission weight and perform transmission weighting on the transmission signal, A wireless communication method for transmitting a transmission signal,
Calculating an eigenvector and an eigenvalue obtained from a transmission side correlation matrix of a channel response matrix corresponding to a communication partner transmitting common data;
Determining which eigenvector to use for each communication partner;
Obtaining an inner product value of the eigenvector determined to be used for a certain communication partner and the eigenvector of the other communication partner;
When the eigenvalue for a certain communication partner is used from the inner product value, the received signal received by the other communication partner is estimated, and the correction value is set to the selected eigenvector so that the same received signal is received by each communication partner. Multiplying, adding, and determining a common transmission weight;
Calculating an orthogonal spatial channel response matrix consisting only of components orthogonal to the reception beam of the receiving apparatus when using the common transmission weight obtained from the channel response matrix;
Determining again as a second transmission weight using an orthogonal spatial channel response matrix;
A wireless communication method comprising: A wireless communication method according to claim 3, wherein
Calculate the common transmission weight from the channel response matrix,
Calculate orthogonal spatial channel response matrix from common transmission weight and channel response matrix,
Calculating a second common transmission weight from the orthogonal spatial channel response matrix;
Calculating a second orthogonal spatial channel response matrix from the second common transmission weight and the orthogonal spatial channel response matrix;
Calculating a third common transmission weight from the second orthogonal spatial channel response matrix;
A wireless communication method characterized by determining a transmission weight of an arbitrary number of communication sequences by repeating the above processing. Equipped with multiple antenna elements, estimate the channel response matrix representing the propagation environment between the antennas of the communication partner, determine the transmission weight and perform transmission weighting on the transmission signal, A wireless communication method for transmitting a transmission signal,
Dividing the communication partners that transmit the same information into the same group, and dividing the communication partners to be transmitted into a plurality of groups;
When determining a transmission weight to a certain group, defining an interference space basis vector from a channel response matrix of a communication partner not belonging to the group;
Calculating an orthogonal spatial channel response matrix that is an orthogonal component with respect to the interference space basis vector using the channel response matrix of the communication partner of the group;
Calculating an eigenvector and an eigenvalue obtained from a transmission side correlation matrix of an orthogonal spatial channel response matrix corresponding to a communication partner transmitting common data;
Determining which eigenvector to use for each communication partner;
Obtaining an inner product value of the eigenvector determined to be used for a certain communication partner and the eigenvector of the other communication partner;
When the eigenvalue for a certain communication partner is used from the inner product value, the received signal received by the other communication partner is estimated, and the correction value is set to the selected eigenvector so that the same received signal is received by each communication partner. Multiplying, adding, and determining as a common transmission weight;
A wireless communication method comprising: Equipped with multiple antenna elements, estimate the channel response matrix representing the propagation environment between the antennas of the communication partner, determine the transmission weight and perform transmission weighting on the transmission signal, A wireless communication method for transmitting a transmission signal,
Dividing the communication partners that transmit the same information into the same group, and dividing the communication partners to be transmitted into a plurality of groups;
When determining a transmission weight to a certain group, defining an interference space basis vector from a channel response matrix of a communication partner not belonging to the group;
Calculating an orthogonal spatial channel response matrix that is an orthogonal component with respect to the interference space basis vector using the channel response matrix of the communication partner of the group;
Calculating an eigenvector and an eigenvalue obtained from a transmission side correlation matrix of an orthogonal spatial channel response matrix corresponding to a communication partner transmitting common data;
Determining which eigenvector to use for each communication partner;
Obtaining an inner product value of the eigenvector determined to be used for a certain communication partner and the eigenvector of the other communication partner;
When the eigenvalue for a certain communication partner is used from the inner product value, the received signal received by the other communication partner is estimated, and the correction value is set to the selected eigenvector so that the same received signal is received by each communication partner. Multiplying, adding, and determining a common transmission weight;
Calculating a second orthogonal spatial channel response matrix consisting only of components orthogonal to the reception beam of the reception side device when using the obtained common transmission weight of the orthogonal spatial channel response matrix of the group;
Determining again a second common transmission weight using an orthogonal spatial channel response matrix;
A wireless communication method comprising: The wireless communication method according to claim 6, comprising:
The common transmission weight is calculated from the orthogonal spatial channel response matrix of communication partners belonging to the group,
Calculating a second orthogonal spatial channel response matrix from the common transmission weight and the orthogonal spatial channel response matrix;
Calculating a second common transmission weight from a second orthogonal spatial channel response matrix;
Calculating a third orthogonal spatial channel response matrix from the second common transmission weight and the second orthogonal spatial channel response matrix;
Calculating a third common transmission weight from the third orthogonal spatial channel response matrix;
A wireless communication method characterized by determining a transmission weight of an arbitrary number of communication sequences by repeating the above processing. The wireless communication method according to claim 6, wherein
A radio communication method characterized in that, when there is one communication partner corresponding to a group, a vector obtained by linear calculation from an orthogonal spatial channel response matrix obtained for the communication partner is used as a transmission weight. The wireless communication method according to claim 1,
A wireless communication method, wherein a first eigenvector is selected as an eigenvector to be selected for each communication partner. The wireless communication method according to claim 1,
A radio communication method characterized by selecting, as eigenvectors to be selected for each communication partner, a vector having a close eigenvalue corresponding to an eigenvector. A transmitter station with multiple antenna elements;
It is composed of a plurality of communication partner stations equipped with one or a plurality of antenna elements,
One or a plurality of signals are transmitted to a plurality of communication partner stations via a MIMO (Multiple Input Multiple Output) channel constituted by a transmitting station and a plurality of communication partner station antenna elements or beams formed on the antenna elements. In a wireless communication apparatus that transmits common transmission data for M _u communication partners in a wireless communication system capable of performing MIMO communication by spatially multiplexing a sequence at the same frequency channel and the same time,
M _T (M _T > 1: integer) antenna elements,
A radio unit connected to each antenna element, converting a received signal into a baseband signal at the time of reception and outputting it to a channel information acquisition circuit; and transmitting a radio signal from the antenna element as a radio signal at the time of transmission;
A channel information acquisition circuit that estimates a channel response matrix for a communication partner from a signal input from a wireless unit, and outputs a channel response matrix of a communication partner to be transmitted to a transmission weight candidate calculation circuit when a communication partner and a transmission signal are determined When,
Based on the channel response matrix input from the channel information acquisition circuit, a transmission weight candidate calculation circuit that calculates transmission weight candidates for each communication partner,
A transmission weight candidate for each communication partner output from the transmission weight candidate calculation circuit is multiplied by a correction value, added together, a transmission weight is determined, output to the transmission signal conversion circuit, and applied to each communication sequence. A common transmission weight calculation circuit that outputs to the modulation circuit and the data division circuit;
A transmission weight determination block including the channel response matrix acquisition circuit, a transmission weight candidate calculation circuit, and a common transmission weight calculation circuit;
A data division circuit that divides transmission data into the number of communication sequences according to the modulation method, a modulation circuit that modulates each signal sequence,
A transmission signal conversion circuit that multiplies each modulated communication sequence by the transmission weight determined by the transmission weight arithmetic circuit and outputs the result to the radio unit connected to the corresponding antenna element;
A wireless communication apparatus comprising: The wireless communication device according to claim 11, wherein
The transmission weight determination block includes:
A channel information acquisition circuit that estimates a channel response matrix for a communication partner from a signal input from a radio unit, and outputs a channel response matrix of a communication partner to be transmitted to a transmission weight candidate calculation circuit when a communication partner and a transmission signal are determined When,
Based on the channel response matrix input from the channel information acquisition circuit, a transmission side eigenvector and eigenvalue obtained by singular value decomposition are calculated, and a transmission weight candidate calculation circuit that outputs to the common transmission weight calculation circuit,
From the eigenvector for each communication partner input from the transmission weight candidate calculation circuit, the eigenvector used for obtaining the common transmission weight is determined, and the received signal at the communication partner when the selected eigenvector is used for another communication partner is determined. Estimate and weight the eigenvectors so that the received powers at all communication partners are almost equal, add together, determine the transmission weight, output to the transmission signal conversion circuit, and apply the modulation method applied to each communication sequence A common transmission weight calculation circuit that outputs to the modulation circuit and the data division circuit;
A wireless communication apparatus comprising: The wireless communication device according to claim 11, wherein
The transmission weight determination block includes:
Channel information for estimating the channel response matrix for the communication partner from the signal input from the radio unit, and outputting the channel response matrix of the communication partner for transmission to the transmission weight candidate calculation circuit when the communication partner and the transmission signal are determined An acquisition circuit;
Based on the channel response matrix input from the channel information acquisition circuit or the orthogonal spatial channel response matrix input from the orthogonal spatial channel calculation circuit, the transmission side eigenvector and eigenvalue obtained by singular value decomposition are calculated, and the common transmission weight is calculated. A transmission weight candidate calculation circuit to be output to the calculation circuit;
Determine the eigenvector used to calculate the common transmission weight from the eigenvector for each communication partner input from the transmission weight candidate calculation circuit, and calculate the inner product value of the selected eigenvector and the eigenvector of the channel response matrix of the other communication partner In consideration of leakage of signals to other communication partners when the eigenvector selected for a certain communication partner is used as a transmission weight, the eigenvectors are weighted so that the reception powers of all communication partners are substantially equal, Adding, determining a transmission weight, outputting to a transmission signal conversion circuit and an orthogonal spatial channel arithmetic circuit, a common transmission weight arithmetic circuit outputting a modulation scheme applied to each communication series to the modulation circuit and the data division circuit,
An orthogonal spatial channel response matrix that is orthogonal to the reception beam of the receiving side device when using the transmission weight is calculated from the input transmission weight and the channel response matrix of each communication partner, and is output to the transmission weight candidate calculation circuit. A spatial channel arithmetic circuit;
A wireless communication apparatus comprising: The wireless communication device according to claim 11, wherein
The transmission weight determination block includes:
A communication partner grouping circuit that estimates a channel response matrix for a communication partner from a signal input from the wireless unit, and groups the communication partner that transmits the same information as the same group when the communication partner and the transmission signal are determined. When,
A channel information acquisition circuit that outputs a channel response matrix of a communication partner that performs transmission to an orthogonal spatial channel arithmetic circuit;
A channel response matrix corresponding to a communication partner that does not belong to the kth group and whose transmission weight is not determined, with respect to a channel response matrix of a communication partner that belongs to the kth group that determines the input transmission weight; From the transmission weight input from the transmission weight calculation circuit, the calculated k-th group first interference space basis vector and the orthogonal k-th group first orthogonal spatial channel response matrix are calculated, and the transmission weight candidate calculation circuit An orthogonal spatial channel arithmetic circuit to output,
A transmission weight candidate calculation circuit that calculates a transmission side eigenvector and eigenvalue obtained by singular value decomposition based on the orthogonal space channel response matrix input from the orthogonal space channel calculation circuit, and outputs to the common transmission weight calculation circuit;
Determine the eigenvector used to calculate the common transmission weight from the eigenvector for each communication partner input from the transmission weight candidate calculation circuit, and calculate the inner product value of the selected eigenvector and the eigenvector of the channel response matrix of the other communication partner In consideration of leakage of signals to other communication partners when the eigenvector selected for a certain communication partner is used as a transmission weight, the eigenvectors are weighted so that the reception powers of all communication partners are substantially equal, Adding, determining a transmission weight, outputting to a transmission signal conversion circuit and an orthogonal spatial channel arithmetic circuit, a common transmission weight arithmetic circuit outputting a modulation scheme applied to each communication series to the modulation circuit and the data division circuit,
A wireless communication apparatus comprising: The wireless communication device according to claim 11, wherein:
The transmission weight determination block includes:
From the transmission weight determined in the transmission weight arithmetic circuit or the common transmission weight arithmetic circuit, in the orthogonal spatial channel arithmetic circuit, the channel response matrix orthogonal to the reception beam of the receiving apparatus when this transmission weight is used, or the orthogonal spatial channel By obtaining the response matrix and repeating the process of determining the transmission weight again through the transmission weight candidate calculation circuit, it is possible to calculate the transmission weight for the common communication partner for any number of communication sequences. A wireless communication apparatus comprising a transmission weight arithmetic circuit or a common transmission weight arithmetic circuit, an orthogonal spatial channel arithmetic circuit, and a transmission weight candidate arithmetic circuit. The wireless communication device according to claim 11, wherein:
The transmission weight determination block includes:
A wireless communication apparatus comprising a transmission weight calculation circuit that uses an input eigenvector as a transmission weight when there is one communication partner belonging to a group. The wireless communication device according to claim 11, wherein:
The transmission weight determination block includes:
A transmission weight arithmetic circuit or a common transmission weight arithmetic circuit for selecting a first eigenvector is provided when determining an eigenvector used to obtain a common transmission weight from eigenvectors input to each communication partner inputted from the transmission weight candidate arithmetic circuit. A wireless communication apparatus. The wireless communication device according to claim 11, wherein:
The transmission weight determination block includes:
A transmission weight calculation circuit that selects an eigenvector that takes a value close to the eigenvalue corresponding to the eigenvector when determining the eigenvector used for obtaining the common transmission weight from the eigenvector for each communication partner input from the transmission weight candidate calculation circuit, or Common transmission weight calculation circuit,
A wireless communication apparatus comprising:

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