JP4444300B2 - Wireless communication apparatus and wireless communication method - Google Patents

Description

  The present invention is a wireless communication device that uses the same frequency channel, spatially multiplexes independent signal sequences from a plurality of different transmission antennas, transmits the signals to a plurality of communication partners, and realizes information transmission to the plurality of communication partners, The present invention also relates to a wireless communication method.

In recent years, as the high-speed wireless access system using the 2.4 GHz band or the 5 GHz band, the IEEE802.11g standard, the IEEE802.11a standard, and the like are remarkable. In recent years, the IEEE802.11n standard that enables the frequency utilization efficiency to be increased by a multiple input multiple output (MIMO) technique is also in commercial use, and it is considered that the speed and capacity of wireless communication are further increased.
As a technique for that purpose, a Multiuser (MU: Multi-User) -MIMO technique is known. In MU-MIMO technology, by simultaneously transmitting to multiple communication partners and viewing the receiving antennas of the entire communication partner like a virtual array, it is possible to effectively use space resources and increase frequency utilization efficiency. Can do.

Many of the MU-MIMO techniques still require theoretical examination, but attention has been focused on a block diagonalization directivity control method (hereinafter also referred to as a BD method) that can be realized with a realistic calculation amount. With the BD directivity control method, on the transmitting station side, different independent signals are transmitted from a plurality of transmission antennas on the same channel to a plurality of communication partners, and the reception beams formed by the reception weights of the communication partners are A null is formed, and on the receiving music side, a signal is received without causing interference from other communication partners, the received signal is estimated independently for each communication partner, and data is reproduced.
Hereinafter, the number of antenna elements of the transmitting device is M _t , the number of communication partners is Mu, the number of reception antenna elements of the i-th communication partner is M _r (i), and the i-th communication partner is the same time at the same frequency band. An example of a method for determining a communication partner will be described, assuming that the number of communication sequences to be transmitted (number of data streams) is L (i) and Mt ≧ M _r (i).

FIG. 9 is a block configuration diagram of a transmission unit of a communication apparatus based on a conventional BD directivity control method. The communication apparatus 801 shown in FIG. 9 controls the transmission directivity so as to be optimal for the propagation environment, and improves the transmission rate by spatial multiplexing.
The communication device 801 (transmission unit) includes a data output circuit 900-1, a data division circuit 900-2, a modulation circuit 901-1, ..., 901-L, a transmission signal conversion circuit 902, a radio unit 903-1, and a radio unit 903. , 903-M _t , antennas 904-1, 904-2,..., 904-M _t , channel response acquisition circuit 905, communication quality evaluation communication partner selection circuit 906, transmission weight determination circuit 907, and the like. The

The radio units 903-2,..., 903-M _t and the antennas 904-1, 904-2,..., 904-M _t can transmit and receive radio signals, and the channel response acquisition circuit 905 performs transmission. , 904 -M _t and the channel response matrix between the communication partner antennas are estimated. Method of estimating the channel response matrix is not described in detail here, the antenna 904-1,904-2, ..., in _{904-M t,} estimated based on information obtained when performing the reception of the known signal Or can be estimated from information included in feedback information included in the received signal. The channel response matrix estimation information is input to the communication quality evaluation communication partner selection circuit 906. The communication quality evaluation communication partner selection circuit 906 estimates the transmission quality when the communication partners are combined, and the combination of communication partners that satisfies the criteria. Is output to the transmission weight determination circuit 907. The transmission weight determination circuit 907 outputs transmission weights for the respective antennas 904-1, 904-2,..., 904-M _t of each signal series.

Next, when transmission data to be transmitted is input, the data dividing circuit 900-2 divides one system of signals into L signal series and inputs the signals to the modulation circuits 901-1,. . The modulation circuits 901-1,..., 901 -L modulate the input signals by adding a preamble signal for MIMO channel estimation and the like, and then input these signals to the transmission signal conversion circuit 902. Here, is multiplied by the transmission weight to the transmission data, a radio unit 903-2, ..., are input to _{903-M t,} antennas 904-1,904-2, ..., as a radio signal through a _{904-M t} Sent.

ここで、Ｈ_ｉ，ｊｋは送信装置のｋ番目のアンテナ９０４−ｋからｉ番目の通信相手におけるｊ番目のアンテナまでの伝達係数を表す。右特異行列Ｖｉのうち、Ｖ'ｉは固有値に対応する列ベクトル群を、Ｖ"ｉは「０」に対する列ベクトル群である。シングルユーザに対する通信において、Ｖ'ｉの列ベクトルを送信ウェイトとすることで、対応する固有値λ_ｉ，ｊで表せる信号電力を得ることができる。（λ_ｉ，１≧λ_ｉ，２≧…≧λ_{ｉ，Ｍｒ（ｉ）}）数式（１）において、行列の上付き添え字「Ｈ」は共役複素行列であることを示す。 The channel response matrix Hi (M _r (i) × M _t matrix) representing the channel information for the i-th communication partner obtained in the channel response matrix acquisition circuit 905 is the right singular value decomposition by singular value decomposition as shown in equation (1). The matrix Vi (M _t × M _t matrix), the left singular matrix Ui (M _r (i) × M _r (i) matrix), and the square root √λ of the eigenvalues are used as diagonal elements, and the non -diagonal matrix is set to “0”. Can be divided into a matrix D (M _r × M _t matrix).

Here, H _{i, jk} represents a transmission coefficient from the k-th antenna 904-k of the transmission device to the j-th antenna at the i-th communication partner. Of the right singular matrix Vi, V′i is a column vector group corresponding to the eigenvalue, and V ″ i is a column vector group for “0”. In communication for a single user, by using a column vector of V′i as a transmission weight, signal power that can be expressed by a corresponding eigenvalue λ _{i, j} can be obtained. (Λ _{i, 1} ≧ λ _{i, 2} ≧ ... ≧ λ _{i, Mr (i)} ) In equation (1), the superscript “H” of the matrix indicates that it is a conjugate complex matrix.

ここで、Ｌ（ｉ）はｉ番目の通信相手への送信に用いる通信系列数（データストリーム数）、σ^２は熱雑音の分散値である。 The frequency utilization efficiency achievable for a single user is as follows by selecting V ′ _{i, L (i)} that are _{L (i)} column vectors of the right singular matrix V′i as transmission weights. Can be represented.

Here, L (i) is the number of communication sequences (number of data streams) used for transmission to the i-th communication partner, and σ ² is a thermal noise variance value.

Next, means for selecting a communication partner by the BD method for multi-users will be described. Here, it is assumed that among the communication partners of the multi-user Mu who wants to communicate, the communication is blocked for each communication partner of Mu ′ (t) and transmission is simultaneously performed to the plurality of communication partners at the t-th timing. It is assumed that the numbers of communication partners to be transmitted at the t-th timing are lt (1) to lt (Mu ′ (t)) and iεU (l).
Hereinafter, a method for evaluating the transmission quality when performing transmission by the BD method to Mu ′ (l) communication partners will be described.

ここで、lt(i)はｔ番目のタイミングで同時に送信する通信相手の中でｉ番目の通信相手の番号である。Ｒlt(j)はlt(j)番目の通信相手に仮定した受信ウェイトであり、対角行列とすれば、受信ウェイトの仮定ナシの条件となる。このＨ^＋ _lt(i)(t)に対して特異分解値を行うと、

と表すことができ、Ｖ^＋ _lt(i)(t)は固有値Ｄ^＋ _lt(i)(t)に対応するベクトルであり、Ｖ⁻ _lt(i)(t)は固有値がない、もしくは、固有値０に対応するヌル空間ベクトルである。 First, a method for evaluating the transmission capacity that can be achieved by the i-th communication partner among the communication partners of Mu ′ (t) will be described.
H ⁺ _{lt (i)} is expressed by the following equation as a set matrix of channel response matrices of communication partners that simultaneously transmit to the same frequency band at the t-th timing other than the lt (i) -th communication partner.

Here, lt (i) is the number of the i-th communication partner among the communication partners simultaneously transmitted at the t-th timing. Rlt (j) is a reception weight assumed for the lt (j) -th communication partner, and if it is a diagonal matrix, it is a condition for an assumption of reception weight. When a singular decomposition value is applied to this H ⁺ _{lt (i)} (t),

V ⁺ _{lt (i)} (t) is a vector corresponding to the eigenvalue D ⁺ _{lt (i)} (t), and V ⁻ _{lt (i)} (t) has no eigenvalue or is an eigenvalue A null space vector corresponding to zero.

ここで、Ｖ^† _lt(i)は固有値に対応する固有ベクトル、Ｖ^†† _lt(i)は「０」に対応する固有ベクトルである。Ｄ^† _lt(i)(t)の対角成分の二乗値であるヌル空間固有値λ^† _lt(i),1、…、λ^† _{lt(i),Mr(lt(i))}に対応する品質が得られることになる。
マルチユーザにおける達成可能な周波数利用効率は、送信ウェイトとして、右特異行列Ｖ⁻ _lt(i)Ｖ^† _lt(i)のうちのL(i)個の列ベクトルＷ_lt(i)L(i)を送信ウェイトとして選択することで、次式のように示される。

ここで、Ｒ'_lt(i)はlt(i)番目の通信相手で復号に用いる受信ウェイトである。 Here, when transmission is performed in the transmission space of V ⁻ _{lt (i)} (t), no interference occurs with the reception weight of the communication partner other than lt (i) at the t-th timing. Therefore, in order to evaluate the communication quality obtained in this transmission space, the singularity obtained by multiplying the channel response matrix of the lt (i) th communication partner by the null space weight V ⁻ _{lt (i)} (t). Calculate the value.

Here, V ^† _{lt (i)} is an eigenvector corresponding to the eigenvalue, and V ^†† _{lt (i)} is an eigenvector corresponding to “0”. The quality corresponding to the null space eigenvalues λ ^† _{lt (i), 1} ,..., Λ ^† _{lt (i), Mr (lt (i))} , which is the square value of the diagonal component of D ^† _{lt (i)} (t) Will be obtained.
The frequency utilization efficiency achievable in multi-user is as follows: L (i) column vectors W _{lt (i) L (i) in} the right singular matrix V ⁻ _{lt (i)} V ^† _{lt (i)} Is selected as the transmission weight, the following equation is obtained.

Here, R ′ _{lt (i)} is a reception weight used for decoding by the lt (i) th communication partner.

Q. H. Spencer, A. L. Swindlehurst, and M. Haardt, "Zero-Forcing Methods for Downlink Spatial Multiplexing in Multiuser MIMO Channels," IEEE Trans. Sig. Proceeding, vol.52, issue 2, Feb.2004, pp.461-71.

As described above, for a plurality of communication partners, it is possible to obtain a high transmission capacity by spatial multiplexing at the same time and in the same frequency band, but in the method described above, the combination of communication partners is: “ _Mu C _{Mu ′ (l)} ” exists for all communication partners Mu, and for each combination, the null space eigenvalue λ ^† for each communication partner is calculated by the above method, and the optimum combination of communication partners is determined. To do so requires enormous computational processing.

  The present invention has been made in view of the above points, and there are a plurality of communication partners, and different signal sequences are transmitted to one or more communication partners among them at the same time and in the same frequency band. In this case, an object of the present invention is to provide a wireless communication apparatus and a wireless communication method for easily determining transmission characteristics when communication is performed by a combination of one or more communication partners.

  In order to achieve the above-described object, the present invention provides a wireless communication that includes a plurality of antenna elements, selects a communication partner when transmitting signals to the same frequency band at the same time, and performs communication. A method of calculating a transmission space basis vector for each communication partner performing communication, and a Block Diagonarization (BD) algorithm when a communication partner transmitting at the same time and in the same frequency band is selected from the transmission space vector The method includes the steps of estimating the amount of signal power degradation that occurs in the case of using, and selecting communication partners that best match a predetermined condition from the estimated amount of degradation.

  In addition, the present invention is a wireless communication method that includes a plurality of antenna elements, selects a communication partner when transmitting a signal to the same frequency band at the same time, and performs communication. A signal generated when using a block diagonal algorithm (BD) algorithm when a communication partner to be transmitted in the same frequency band is selected from the step of calculating a transmission space basis vector for each communication partner performing And a step of estimating a power degradation amount, and a step of selecting a transmission mode comprising a modulation scheme and a coding rate from the estimated degradation amount.

  In addition, the present invention can transmit one or a plurality of signal sequences to a plurality of communication partner stations by spatially multiplexing at the same frequency channel and the same time from a transmission device including a plurality of antenna elements. A wireless communication device in a wireless communication system, comprising two or more antennas, connected to each antenna element, and at the time of reception, converts a received signal into a baseband signal and outputs it to a channel information acquisition circuit, A radio unit that transmits a transmission signal as a radio signal from an antenna element at the time of transmission, a channel information acquisition circuit that estimates channel information for a communication partner from a signal input from the radio unit, and outputs the channel information to a transmission space vector arithmetic circuit; A transmission space vector calculation circuit for calculating a transmission space vector group based on the channel information input from the channel information circuit. And from the transmission space vector group input from the transmission space vector arithmetic circuit, a signal power deterioration amount estimation circuit that estimates a signal power deterioration amount generated when combining communication partners, and outputs to a communication partner selection circuit, Based on the deterioration amount input from the signal degradation amount estimation circuit, a communication partner is selected, and the communication partner selection circuit that outputs the selected communication partner to the transmission weight calculation circuit, and the channel information of the selected communication partner, A transmission weight calculation circuit that is acquired from the channel information acquisition circuit, determines a transmission mode including a transmission weight, a modulation scheme, a coding rate, and an interleaving method, and outputs the transmission mode to a data division circuit and a transmission signal conversion circuit, and transmission data Is divided into the number of communication sequences according to the modulation scheme, a modulation circuit that modulates the transmission data divided into the signal sequences, A transmission signal conversion circuit that multiplies the transmission data modulated by the transmission weight determined by the transmission weight calculation circuit and outputs the result to the radio unit connected to the corresponding antenna element. To do.

  According to the present invention, when performing MIMO communication using a spatial weight for one or more signal sequences on the same frequency channel to a plurality of communication partners (stations), an optimal transmission weight is used. By selecting this combination, it is possible to realize good communication characteristics.

  Hereinafter, preferred embodiments of a wireless communication apparatus according to the present invention will be described in detail with reference to the accompanying drawings. In the following description and the accompanying drawings, the same reference numerals are given to components having substantially the same functional configuration, and redundant description is omitted.

FIG. 1 is a block configuration diagram of a transmission unit of radio communication apparatus 1 according to the present embodiment of the present invention. 1 includes a data output circuit 100-1, a data division circuit 100-2, modulation circuits 101-1,..., 101-L, a transmission signal conversion circuit 102, and a wireless unit 103-. _{1,103-2, ..., 103-M t} , antennas _{104-1,104-2, ..., 104-M t} , the channel response obtaining circuit 105, the transmission space vector calculation circuit 106, the signal degradation amount estimation circuit 107, a communication It comprises a partner selection circuit 908, a transmission weight calculation circuit 109, and the like. The channel response acquisition circuit 105, the transmission space vector calculation circuit 106, the signal degradation amount estimation circuit 107, the communication partner selection circuit 908, and the transmission weight calculation circuit 109 constitute a communication partner determination block 110.

Radio section _{103-1,103-2, ..., 103-M t} , antennas 104-1,104-2, ..., _{104-M t} is capable of transmitting and receiving radio signals, the wireless unit 103 - 1, 103-2, ..., 103-M _t , the channel response acquisition circuit 105 communicates with each antenna 104-1, 104-2, ..., 104-M _t of the transmitter. A channel response matrix between each antenna of the other party or between the receiving beams is estimated. Method of estimating the channel response matrix is not described in detail here, the antenna 104-1, 104-2, ..., the _{104-M t,} estimated based on information obtained when performing the reception of the known signal Or can be estimated from information included in feedback information included in the received signal.

  When selecting a communication partner, the channel response matrix of the corresponding communication partner is input to the transmission space vector arithmetic circuit 106. The transmission space vector calculation circuit 106 calculates a transmission space vector group for each communication partner and outputs it to the signal degradation amount estimation circuit 107. The signal degradation amount estimation circuit 107 estimates the attenuation amount of the signal power when the BD method is used by calculation using the transmission space vector, and outputs the result to the communication partner selection circuit 108.

The communication partner selection circuit 108 selects a communication partner that best meets the condition from a product of the estimated attenuation amount of the communication signal and compares it with a predetermined reference value stored, and outputs the communication partner to the transmission weight calculation circuit 109. The transmission weight circuit 109 obtains a transmission weight for the selected communication partner using the BD algorithm, determines a transmission mode including quality, modulation scheme, coding rate, interleaving method, and the like in each communication stream, and the data output circuit 100-1 , 101-L, data division circuit 100-2, modulation circuit 101-1,..., 101-L, and transmission signal conversion circuit 102.

The data dividing circuit 100-2 divides the transmission data transmitted from the data output circuit 100-1 into L signal series, and inputs them to the modulation circuits 101-1, ..., 101-L. Here, the modulation circuits 101-1,..., 101 -L modulate the input signal by adding a preamble signal or the like for MIMO channel estimation, and then input these signals to the transmission signal conversion circuit 102. . Here, is multiplied by the transmission weight to the transmission data, a radio unit 103-1, ..., are input to _{103-M t,} antenna 104-1, 104-2, ..., through _{104-M t} Transmitted as a radio signal.

数式（８）ではユーザ選択の説明のため、lt(i)番目の通信相手として表記したが、ｉ番目として表記しても一般性は崩れない。従って、マルチユーザＭＩＭＯについても同様にｉ番目として表記すると数式（８）は次式のようになる。

Hereinafter, the principle of selecting a communication partner in the wireless communication device 1 will be described in detail. In the frequency utilization efficiency achievable in the propagation path shown by the equation (5), λ ^† _{lt (i), 1} ,..., Λ ^† _{lt (i), Mr (lt (i))} >> σ ² When communication with a high SNR (Signal to Noise ratio) is considered, Equations (2) and (6) are as follows.

In the formula (8), for the explanation of the user selection, it is described as the lt (i) th communication partner, but even if it is expressed as the i th, the generality is not lost. Accordingly, when multi-user MIMO is similarly expressed as i-th, Equation (8) becomes as follows.

と減衰量ａ_ｉ，ｊを定義する（０≦ａ_ｉ,ｊ≦１）。減衰量ａ_ｉ，ｊを用いて、マルチユーザＭＩＭＯの達成可能な周波数利用効率の、シングルユーザＭＩＭＯの達成可能な周波数利用率からの増大度は次式で表される。

Furthermore, λ ^† _{i, j} is expressed using λ _{i, j} ,

And attenuation amounts a _{i, j} are defined (0 ≦ a _{i, j} ≦ 1). Using the attenuation amount a _{i, j} , the degree of increase in the frequency utilization efficiency achievable by multi-user MIMO from the achievable frequency utilization ratio of single-user MIMO is expressed by the following equation.

こうして、同時に通信を行う通信相手数に対する通信特性が得られる。 Here, A _i is a product of attenuation coefficients. In single-user MIMO communication, since transmission to a plurality of communication partners cannot be performed in the same time domain, the effect of increasing the frequency utilization efficiency of multi-user MIMO increases as the number of communication partners increases. The frequency utilization efficiency that can be achieved in total is expressed by Equation (12) for single user MIMO and by Equation (13) for multi-user.

In this way, communication characteristics with respect to the number of communication partners performing simultaneous communication can be obtained.

Next, calculation of communication characteristics with respect to the number of communication partners will be described.
(i) L (1) = Mr (1), L (2) = Mr (2), M′u (t) = 2
Here, consider a case where the number of users is “2” and the number of data streams is equal to the number of receiving antenna elements of the corresponding terminal. The channel response matrixes of the _first communication partner and the second communication partner are set as H ₁ and H _2, and a total product value A ₁ of attenuation values of eigenvalues corresponding to the first communication partner is obtained. Transmission weights W _{1 and L (1)} corresponding to the first communication partner are expressed by the following equations.

と表すことができる。数式（１５）の３行目から４行目でＲ_１’Ｕ_１、６行目から７行目でＶ_１ ^†Ｖ_１ ^†Ｈがそれぞれ除けるのは、受信素子数とデータストリームが同数であるためである。Ｖ_１ ^†のランクが受信素子数であり、かつＨ_１Ｖ_２"の固有ベクトルであるため、Ｈ_１Ｖ_２"に乗算しても固有値の分布に何ら影響しない。 In Equation (10), the product A _{1 of} attenuation is obtained from Equation (9).

It can be expressed as. The reason why R ₁ 'U ₁ is removed from the 3rd to 4th lines and V ₁ ^† V ₁ ^{† H} is removed from the 3rd to 4th lines of Equation (15) is the same as the number of receiving elements and the number of data streams. Because. V ₁ is the number of receiving elements rank ^†, and _"since the eigenvector _{of, H 1 V 2" H 1} V 2 no effect on the distribution of the eigenvalues be multiplied to.

が成り立つ。数式（１６）によれば、信号劣化量推定回路１０７は、新たに固有値に対応しない信号空間Ｖ_１"やＶ_２"を求めることなく、数式（１６）を求めるだけで２つの通信相手における信号減衰量の積を得ることができる。複素数の乗算回数でこの演算負荷を比較すると、直交化法などを用いてＶ_１"やＶ_２"を求める場合は３乗のオーダーの計算であるのに対し、数式（１６）の計算は送信素子数に対しては１乗のオーダーであり、演算量は大変削減されることとなる。この場合の各通信相手に対する達成可能な周波数利用効率は次式で表される。

In addition, Equation (13) and det (I−A ^H A) = det (I−AA ^H )
From the relationship

Holds. According to the equation (16), the signal degradation amount estimation circuit 107 does not newly obtain the signal space V ₁ ″ or V ₂ ″ that does not correspond to the eigenvalue, but merely obtains the equation (16), so that the signals at the two communication partners can be obtained. A product of attenuation can be obtained. Comparing this calculation load with the number of multiplications of complex numbers, when V ₁ "or V ₂ " is obtained using the orthogonalization method or the like, the calculation of the formula (16) is transmitted while it is a calculation of the third power. The number of elements is on the order of the first power, and the amount of calculation is greatly reduced. In this case, the achievable frequency utilization efficiency for each communication partner is expressed by the following equation.

(ii) L (i) = Mr (i), i = 1, 2,..., M′u (t)
Next, consider a case where the number of users is M′u (t) and the number of data streams is equal to the number of receiving antenna elements of the corresponding terminal. The channel response matrix of the _first to M′u (t) communication partners is H ₁ ,..., H _{M′u (t),} and the total product value A ₁ of the attenuation values of the eigenvalues corresponding to the first communication partner. Ask for. Here, for a set matrix H ⁺ ₁ of channel response matrices of communication partners other than the first one that transmits to the same frequency band at the same timing, corresponding to the first communication partner of single user MIMO for each communication partner, Perform singular value decomposition.

と表すことができる。数式（１９）の３行目から４行目でＶ_１ ^†Ｖ_１ ^†Ｈが除けるのは、受信素子数とデータストリームが同数であるため、Ｖ_１ ^†のランクが受信素子数であり、かつＨ_１Ｖ_１ ⁻の固有ベクトルであるため、Ｈ_１Ｖ_１ ⁻に乗算しても固有値の分布に何ら影響しないためである。 Therefore, transmission weight _{W 1} corresponding to the first communication _{partner, L (t)} is _V ¹ - can be expressed as _{V 1} ^†. V ₁ ^† is a transmission side eigenvector of HV ₁ ⁻ . The total product value A ₁ of the attenuation amount is obtained from Equation (15).

It can be expressed as. The reason why V ₁ ^† V ₁ ^{† H} is removed from the third to fourth lines of Equation (19) is that the number of receiving elements and the number of data streams are the same, so the rank of V ₁ ^{† is} the number of receiving elements, and because it is the ^{_{eigenvector, H 1 V 1 - - H}} 1 V 1 is because no effect on the distribution of the eigenvalues be multiplied to.

ここで、（Ｖ_１ ^＋ Ｖ_１ ⁻）はＱＲ分解におけるＱに対応する（Ｍ_ｔ×Ｍ_ｔ）のユニタリ行列、Γ_１は（Ｍ_ｔ×Ｌ^＋(1)）の上三角行列である。Ｌ^＋(1)は１番目の通信相手に形成するデータストリーム数の和である。上三角行列Γ_１の「０」でない要素を含む、上側の（Ｌ^＋(1)×Ｌ^＋(1)）行列をΓ_１ ^＋と定義すると、Ｖ_１ ^＋は次式のように表せる。

According to Equation (19), if V ₁ ⁺ is obtained, the frequency utilization efficiency that can be achieved from Equation (13) can be estimated. Since V ₁ ⁺ is the signal space of the second to M′u (t) communication partners, it can be expressed as follows using QR decomposition.

Here, (V ₁ ⁺ V ₁ ⁻ ) is a unitary matrix of (M _t × M _t ) corresponding to Q in QR decomposition, and Γ ₁ is an upper triangular matrix of (M _t × L ⁺ (1)). L ⁺ (1) is the sum of the number of data streams formed in the first communication partner. If an upper (L ⁺ (1) × L ⁺ (1)) matrix including elements other than “0” of the upper triangular matrix Γ ₁ is defined as Γ ₁ ⁺ , V ₁ ⁺ can be expressed as the following equation.

数式（２２）によれば、信号劣化量推定回路１０７は新たに固有値に対応しない信号空間Ｖ_１"やＶ_２"を求めることなく、数式（２２）を求めるだけで２つのある組み合わせにおける通信相手に対する信号減衰量の積を得ることができる。
例えば、通信相手が「３」の場合、数式（２２）は次式となる。

Therefore, Equation (19) is as follows.

According to the equation (22), the signal degradation amount estimation circuit 107 does not newly obtain the signal space V ₁ ″ or V ₂ ″ that does not correspond to the eigenvalue, but merely obtains the equation (22), and the communication partner in the two combinations. Can be obtained as a product of signal attenuation with respect to.
For example, when the communication partner is “3”, Equation (22) is as follows.

よって、数式（２３）の一行目のｆ２部において、（Ｌ(1)×Ｌ(1)）行列のΞ _１ 、Ξ _２ の演算を行えば、減衰量Ａ_１は数式（２３）を用いることによって、ＢＤ法により直接演算するよりも簡易に求めることができる。

here,

Accordingly, if the calculation of 目の ₁ and 数 式 ₂ of the (L (1) × L (1)) matrix is performed in the f2 part of the first row of Equation (23), Equation (23) is used as the attenuation A _1. Therefore, it can be obtained more easily than the direct calculation by the BD method.

  Even when there are more communication partners than “3”, the fifth line f1 part of the formula (22) is a Hermitian matrix composed of special elements, so that the inverse matrix can be easily calculated from the actual matrix size. Is possible.

(iii) L (i) ≦ Mr (i), i = 1, 2,..., M′u (t)
Next, consider a case where the number of users is M′u (t) and the number of data streams is equal to or less than the number of receiving antenna elements of the corresponding terminal. In this case, the product A ₁ of the attenuation amount for the first communication partner is approximated from Equation (19) as follows:

と定義した場合、Ｖ_１ ^’＋は（Ｍ_ｔ×Ｌ(1)）行列、Ｖ_１ ^’−は（Ｍ_ｔ×（Ｍ_ｔ−Ｌ(1)））行列となる。
Ｖ_１ ^’†は、Ｈ_１Ｖ_１ ^’−を特異値分解した際に得られる固有値に対応する固有ベクトルであり、次式となる。

Here, V ₁ ^{′ ″} is an L (1) -dimensional basis vector extracted from the vector space of V ₁ .

V ₁ ^{′ +} is a (M _t × L (1)) matrix, and V ₁ ^{′ −} is a (M _t × (M _t −L (1))) matrix.
V ₁ ^{′ †} is an eigenvector corresponding to the eigenvalue obtained when singular value decomposition is performed on H ₁ V ₁ ^{′ −,} and is expressed by the following equation.

ここで、α_１は１以下の係数であり、データストリーム数が受信素子数に近いほど、また、送信素子数が多いほど「１」に漸近する。この値は、実環境やシミュレーション等により経験的に設定される値である。 Unlike the case of the equation (19), the equation (25) cannot omit V ₁ ^† V ₁ ^{† H.} Therefore, to estimate the product A ₁ attenuation by approximation. Equation (25) can be expressed as:

Here, α ₁ is a coefficient of 1 or less, and gradually approaches “1” as the number of data streams approaches the number of receiving elements and as the number of transmitting elements increases. This value is set empirically by the actual environment, simulation, or the like.

When the number of data streams to each communication partner is equal to or less than the number of receiving elements, the BD method shifts the communication space so as not to affect each other by updating the reception weight of Equation (3). Improve communication quality. In this case, in Equation ^{_{(27), V 1 ''}} ' is V _1' than the selected high corresponding to eigenvalues L (1) eigenvectors of, it is to chose eigenvector corresponding to a low eigenvalue The amount of attenuation can be small. Therefore, as V ₁ ^{′ ″} , a different combination is selected from V ₁ ′, and the average of the estimated values obtained from A ₁ is calculated by Equation (28), or a value added with a certain weight is used as the attenuation amount. Can do.

For example, using V ₁ ^{′ ″} that has selected the eigenvector of L (1) from the one with the highest eigenvalue, the product of the attenuation obtained from Equation (27) is A ₁ ′, and L ( 1) Among the eigenvectors, an eigenvector group obtained by replacing the L (1) th or (L (1) -1) th eigenvector with the (L (1) +1) th eigenvector is obtained using V ₁ ^{″ ″.} Let A ₁ ″ and A ₁ ^′ ″ denote the products of the obtained attenuation amounts. Here, A ₁ ′ estimated from the eigenvectors corresponding to the higher eigenvectors becomes A ₁ ″ and A ₁ ^′ ″. In the case of taking the largest value in comparison, it can be considered that the transmission weight associated with this high eigenvector converges even after repeated calculations, and A ₁ ′ can be used as A ₁ to estimate the frequency utilization efficiency. Assuming that A ₁ ″ and A ₁ ^′ ”are larger than A ₁ ′, A ₁ is defined as β′A ₁ ′ + β” A ₁ ″ + β ^{′ ″} A ₁ ^{′ ″} , β ′ + β ″ + β ^''' = 1,
If, it is possible to increase the estimation accuracy of the product A ₁ attenuation by calculating.

Next, a method of selecting a communication partner when the assumed correct product A ₁ of the estimated attenuation by the above method will be described. For example, consider a case where the communication partner is “20”, M′u (t) users are multiplexed and transmitted to all communication partners in 10 transmission time intervals. When the first to M′u (t) th communication partners are combined, the frequency utilization efficiency achievable by the BD method is expressed by the following equation.

と、表せる。 Here, C _{m, t} is the achievable frequency utilization efficiency obtained in the t-th transmission time interval by the BD method, and At _{, j} are eigenvalues generated in the i-th communication partner in the t-th transmission time interval. It is the product of attenuation. Taking the ratio of the frequency utilization efficiency that can be achieved by a single user,

It can be expressed.

  Assuming that the communication partner M′u (t) selected at each timing in the equation (30) does not change by the combination of the constant Mu and the number of data streams L (i), the second line of the equation (30) is changed. Since the integral value of one term is always constant, the effect of communication by the BD method is determined by the second term. That is, when determining the combination of communication partners, a value that is proportional to or inversely proportional to A that is obtained while calculating the attenuation A or A can be used as the determination value.

In addition, when M′u (t) is changed according to each transmission timing, it is desirable to increase Mu (t) for a communication partner whose value of the f3 part of Expression (30) is large. This indicates that the higher the frequency utilization efficiency Cs _{, t} that can be achieved by a single user, the greater the effect of increasing the communication partner multiplicity M′u (t) by the BD method. From this, it is possible to reduce the amount of calculation for selecting a communication partner by performing grouping with C _{s and t} in advance and determining M′u (t) allowable for each communication partner.

  Further, when determining the communication partner, the calculation for obtaining the combination of the two communication partners is overwhelmingly smaller than the case of combining more (three or more) communication partners. Therefore, by first evaluating the product of attenuation between two communication partners, grouping together communication partners with smaller attenuation, reducing the number of communication partners to be considered, and considering multiplexing of three or more communication partners The amount of calculation can be reduced.

  In addition, the above-described calculation method can be applied to a case where a BD method is additionally used in orthogonal frequency division multiplexing or code division multiplexing, or a case where a multi-user MIMO transmission technique other than the BD method is used. In frequency division multiplex communication, the attenuation of eigenvalues by the method of the present invention is estimated for channel response matrices of all frequency bands, and a communication partner is selected using the sum or average of them. At this time, not only the information of all frequency bands is used, but also the channel response matrix of one or a plurality of frequency bands can be selected, and the communication partner can be selected from the results. The frequency band to be selected can be determined in advance or a frequency band having a high SNR can be selected. In orthogonal frequency division multiple access, the method of the present invention is applied using channel response matrices of all frequency bands or channel response matrices of one or more frequency bands as communication partners to be multiplexed with respect to frequency blocks. It is also possible to determine a communication partner to be selected for the corresponding frequency block from the result.

と表すことができる。数式３１の３行目の括弧内の値はマルチユーザＭＩＭＯ送信時にｉ番目の通信相手のｊ番目のデータストリームに対応するＳＮＲの期待値になっており、このように推定されたＳＮＲを元に、伝送モードを決定できる。 As described above, the singular value decomposition is performed on the selected communication partner as shown in Equation (5) to obtain the eigenvalue λ ^† , and this eigenvalue corresponds to the SNR (Signal to noise ratio) of the communication path. Thus, an appropriate transmission mode can be determined for each data stream of the communication partner to be purchased. Alternatively, the transmission mode can be determined from the attenuation amount A. Frequency utilization efficiency in multi-user MIMO transmission to the i-th communication partner can be expressed by Equation 11. Note that the first term on the right side of Equation 11 can be approximated by Equation 7, and rewriting Equation 11:

It can be expressed as. The value in parentheses on the third line of Equation 31 is the expected SNR value corresponding to the j-th data stream of the i-th communication partner during multi-user MIMO transmission, and based on the SNR estimated in this way The transmission mode can be determined.

  FIG. 2 is a flowchart of transmission processing in the wireless communication device 1 according to the first embodiment of the present invention. Before performing communication, the wireless communication apparatus 1 acquires a channel response matrix for a communication partner that performs transmission and transmission quality at the time of single user communication (step S200). The product of the attenuation values of the eigenvalues by the combination of communication partners is estimated (step S201). Using Equation (11), the frequency utilization efficiency when using the BD method is estimated, and a combination of communication partners with a greater improvement than that during single user communication is determined (step S202). Transmission data is generated based on the estimated frequency utilization efficiency or the transmission quality newly estimated in detail by the selected communication partner (step S203). Similarly, communication partners other than the selected communication partner are evaluated for combinations that increase the transmission rate, and transmission is performed sequentially.

  FIG. 3 is a flowchart of a transmission process in the wireless communication apparatus 1 according to the second embodiment of the present invention. Before performing communication, the wireless communication apparatus 1 acquires a channel response matrix for a communication partner that performs transmission and transmission quality during single-user communication (step S300). The maximum multiplex number allowable for each communication partner is determined using the transmission quality at the time of single user (step S301). A product of attenuation values of eigenvalues is estimated with a combination of the maximum number of multiplexing or less (step 302). Using Equation (11), the frequency utilization efficiency when using the BD method is estimated, and a combination of communication partners with a greater improvement than during single user communication is determined (step S303). Transmission data is generated based on the estimated frequency utilization efficiency or the transmission quality newly estimated in detail by the selected communication partner (step S304). Similarly, communication partners other than the selected communication partner are evaluated for combinations that increase the transmission rate, and transmission is performed sequentially.

  FIG. 4 is a flowchart of transmission processing in the wireless communication apparatus according to the third embodiment of the present invention. Before performing communication, the wireless communication device 1 acquires a channel response matrix for a communication partner that performs transmission and transmission quality during single-user communication (step S400). The product of the attenuation values of the eigenvalues when the two communication partners are paired is estimated (step S401). In the combination of two communication partners, communication partners having a smaller attenuation product are grouped (step S402). A product of attenuation values of eigenvalues is newly estimated for a combination of two or more communication partners in the group (step S403).

  Using Equation (11), the frequency utilization efficiency when using the BD method is estimated, and a combination of communication partners that is improved more than that during single-user communication is determined (step S404). Transmission data is generated based on the estimated frequency utilization efficiency or the transmission quality newly estimated in detail by the selected communication partner (step S405). Similarly, communication partners other than the selected communication partner are evaluated for combinations that increase the transmission rate, and transmission is performed sequentially.

  FIG. 5 is a flowchart of transmission processing in the wireless communication apparatus according to the fourth embodiment of the present invention. Before performing communication, the wireless communication apparatus acquires a channel response matrix for a communication partner to perform transmission and transmission quality at the time of single user communication (step S500). The maximum multiplex number allowable for each communication partner is determined using the transmission quality at the time of single user (step S501). A product of attenuation values of eigenvalues is estimated with a combination of the maximum number of multiplexing or less (step 502). It is determined whether or not the product of attenuation is equal to or greater than a prescribed value with respect to the communication partner multiplexing number and the transmission quality at the time of single user (step S503). If it is smaller than the prescribed value in step S503, the number of multiplexed communication partners is decreased (step S504), the number of attenuations of eigenvalues due to the combination of communication partners is estimated again (step S505), and the determination is made (step 503).

  When the value exceeds the specified value in step S503, the frequency utilization efficiency when using the BD method with the combination exceeding the specified value is estimated using Equation (11), and the improvement is greater than that during single user communication. A combination of communication partners is determined (step S506). Transmission data is generated based on the estimated frequency utilization efficiency or the transmission quality newly estimated in detail by the selected communication partner (step S507). Similarly, communication partners other than the selected communication partner are evaluated for combinations that increase the transmission rate, and transmission is performed sequentially.

Regarding the wireless communication method as described above, the effect in the case where the number of receiving antenna elements and the number of data streams to each communication partner are the same will be examined below.
Consider three users as communication partners, and consider that each communication partner has two receiving antennas and performs downlink communication from a base station with eight transmitting elements. The channel response matrix between each communication partner and the base station is given as an 8 × 2 matrix, and each element is defined by a completely uncorrelated and complex Gaussian distribution, and a computer simulation was performed. The average SNR when communication between one communication element and another communication element was performed was set to be 35 [dB]. FIG. 6 shows the result of obtaining the frequency utilization efficiency directly achievable by the BD method from Equation (6) on the y axis, and the frequency utilization efficiency obtained from Equation (11) estimated by the method according to the present invention on the x axis. It is a result. FIG. 6 shows that the points are distributed on the diagonal line, and it can be seen that the frequency use efficiency is estimated with high accuracy.

Next, the effect of the method of the present invention is verified when the number of data streams to each communication partner is equal to or less than the number of receiving antenna elements.
Consider two users as communication partners, and consider that each communication partner has three receiving antennas and performs downlink communication from a base station with eight transmitting elements. The channel response matrix between each communication partner and the base station is given as an 8 × 3 matrix, and each element is defined by a completely uncorrelated and complex Gaussian distribution, and a computer simulation was performed. The average SNR when communication between one communication element and another communication element was performed was set to be 35 [dB].

The frequency utilization efficiency obtained from Equation (27) and Equation (11) was estimated, and in Equation (27), eigenvectors corresponding to high first eigenvalues and second eigenvalues were used as V _i ^{′ ″} . FIG. 7 shows the result of obtaining the frequency utilization efficiency directly achievable by the BD method from Equation (6) on the y axis, and the frequency utilization efficiency obtained from Equation (11) estimated by the method of the present invention on the x axis. It is a figure which shows the result. The direct estimation method based on the BD method is a result obtained by updating the reception weight defined by Equation (3) every time a transmission weight is determined and repeating the calculation five times. As can be seen from FIG. 7, when the number of data streams is lower than the number of receiving elements, the estimation accuracy deteriorates, but a value having a high correlation with the actual frequency utilization efficiency can be estimated.

  Similarly, consider two users as communication partners, and consider that each communication partner has three reception antennas and performs downlink communication from a base station with eight transmission elements. The channel response matrix between each communication partner and the base station is given as an 8 × 3 matrix, and each element is defined by a completely uncorrelated and complex Gaussian distribution, and a computer simulation was performed. The average SNR at the time of performing communication for each element of transmission / reception between each communication partner was set to be 35 [dB].

The frequency utilization efficiency obtained from Equation (27) and Equation (11) is estimated. In Equation (27), eigenvectors corresponding to the high first eigenvalue and second eigenvalue are used as V _i ^{″ ″} , As V ^{′ +} _i in 19), the first eigenvalue having a high value, the eigenvector corresponding to the second eigenvalue, and the eigenvector corresponding to the first eigenvalue and the third eigenvalue of another communication partner other than the communication partner , The eigenvectors corresponding to the high eigenvalues are selected as the products A ^′ _i and V _i ^{′ ”of} attenuation obtained from the respective corresponding to the high eigenvalues, and the first and third eigenvectors are used as V ^{′ +} _i . Attenuation products A ^″ _i , V _i ^{′ ”} calculated in the above are selected as eigenvectors corresponding to high eigenvalues, and attenuation products A ^′ calculated using the first and second eigenvectors as V ^{′ +} _i are selected. _{^'' i} the its Each _{calculated, β'A 1 '+ β "A} 1" + β''' A 1 as the attenuation amount ^{_{A i ''',β'}} + β "+ β '''= 1,
The value that can be defined by is used.

here,
When A ^′ _i > A ^″ _i and A ^′ _i > A ^{′ ″} _i , β ′ = 1, β ″ = β ^{′ ″} = 0,
_{^{A 'i <A'' i ,A'}} i> A ''' at the time of _i is, β' = 0.75, β " = 0.25, β '''= 0,
When A ^′ _i > A ^″ _i and A ^′ _i <A ^{′ ″} _i , β ′ = 0.75, β ″ = 0, β ^{′ ″} = 0.25,
When A ^′ _i <A ^″ _i and A ^′ _i <A ^{′ ″} _i , β ′ = 0.5, β ″ = 0.25, β ^{′ ″} = 0.25,
It was.
FIG. 8 is a diagram showing the results of obtaining the frequency utilization efficiency directly achievable by the BD method from Equation (6) on the y axis and the frequency utilization efficiency estimated by the method of the present invention on the x axis. . The direct estimation method based on the BD method is a result after updating the reception weight defined by Equation (3) every time the transmission weight is determined and performing the calculation five times. By controlling in this way, it is possible to improve the estimation accuracy from FIG.

  As described above, according to the present invention, when performing MIMO communication using one or more signal sequences on the same frequency channel at the same time and using spatial weight for a plurality of communication partners (stations). In addition, it is possible to realize good communication characteristics by selecting an optimal combination of transmission weights.

  1 is recorded on a computer-readable recording medium, and the program recorded on the recording medium is read by a computer system and executed to execute wireless communication. You may go. The “computer system” here includes an OS and hardware such as peripheral devices.

Further, the “computer system” includes a homepage providing environment (or display environment) if a WWW system is used.
The “computer-readable recording medium” refers to a portable medium such as a flexible disk, a magneto-optical disk, a ROM, and a CD-ROM, and a storage device such as a hard disk built in the computer system. Furthermore, the “computer-readable recording medium” dynamically holds a program for a short time like a communication line when transmitting a program via a network such as the Internet or a communication line such as a telephone line. In this case, a volatile memory in a computer system serving as a server or a client in that case, and a program that holds a program for a certain period of time are also included. The program may be a program for realizing a part of the functions described above, and may be a program capable of realizing the functions described above in combination with a program already recorded in a computer system.

  The preferred embodiments of the wireless communication apparatus according to the present invention have been described above with reference to the accompanying drawings, but the present invention is not limited to such examples. It will be apparent to those skilled in the art that various changes or modifications can be conceived within the scope of the technical idea disclosed in the present application, and these naturally belong to the technical scope of the present invention. Understood.

The figure which shows the block configuration of the radio | wireless communication apparatus 1 (transmission part) which concerns on this Embodiment. The flowchart which shows the flow of the transmission process in the 1st Embodiment of this invention. The flowchart which shows the flow of the transmission process in the 2nd Embodiment of this invention. The flowchart which shows the flow of the transmission process in the 3rd Embodiment of this invention. The flowchart which shows the flow of the transmission process in the 4th Embodiment of this invention. The figure which shows the estimation result of the frequency utilization efficiency by the BD method and the method of this invention in case of the number of users 3, the number of transmitting elements 8, and the number of receiving elements 2 The figure which shows the estimation result of the frequency utilization efficiency by the BD method and the method of this invention in the case of the number of users 2, the number of transmitting elements 8, the number of receiving elements 3, and the number of data streams 2 The figure which shows the estimation result of the frequency utilization efficiency by the BD method and the method of this invention in the case of the number of users 2, the number of transmitting elements 8, the number of receiving elements 3, and the number of data streams 2 The figure which shows the block configuration of the conventional radio | wireless communication apparatus 801 (transmission part).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ......... Wireless communication apparatus 100-1 ......... Data output circuit 100-2 ......... Data division circuit 101-1, ..., 101-L ......... Modulation circuit 102 ......... Transmission signal conversion circuit 103-1 , 103-2,..., 103-M _t ... Wireless section 104-1, 104-2,..., 104-M _t .. Antenna 105... Channel information acquisition circuit 106. Circuit 107... Signal degradation amount estimation circuit 108... Communication partner selection circuit 109.

Claims (4)

A wireless communication method comprising a plurality of antenna elements, selecting a communication partner when transmitting a signal to the same time and the same frequency band for a plurality of communication partners, and performing communication,
Calculating a transmission space basis vector for each communication partner performing communication;
From the transmission space vector, the product of the amount of signal power attenuation that occurs when selecting a communication partner to transmit at the same time and the same frequency band,

Or

(A ₁ , A ₂ : values obtained by integrating the attenuation amounts of the first and second communication partners. Mu ′ (l): number of communication partners, I: unit matrix, V ₁ : first Right singular matrix of channel response matrix of communication partner, V ′ ₁ , V ′ ₂ : first, and column vector group corresponding to eigenvalues among right singular matrix of channel response matrix of second communication partner, H: Conjugate complex matrix)
Estimating with
Selecting communication partners that best match a predetermined condition from the product of the attenuation amount; and
A wireless communication method comprising: A wireless communication method comprising a plurality of antenna elements, selecting a communication partner when transmitting a signal to the same time and the same frequency band for a plurality of communication partners, and performing communication,
Calculating a transmission space basis vector for each communication partner performing communication;
From the transmission space vector, the product of the amount of signal power attenuation that occurs when selecting a communication partner to transmit at the same time and the same frequency band,

Or

(A ₁ , A ₂ : values obtained by integrating the attenuation amounts of the first and second communication partners. Mu ′ (l): number of communication partners, I: unit matrix, V ₁ : first Right singular matrix of channel response matrix of communication partner, V ′ ₁ , V ′ ₂ : first, and column vector group corresponding to eigenvalues among right singular matrix of channel response matrix of second communication partner, H: Conjugate complex matrix)
Estimating with
Selecting a transmission mode comprising a modulation scheme and a coding rate from the product of the estimated amounts;
A wireless communication method comprising: Wireless communication in a wireless communication system capable of spatially multiplexing and transmitting one or a plurality of signal sequences at the same frequency channel and the same time to a plurality of communication partner stations from a transmission apparatus including a plurality of antenna elements A device,
Two or more antennas,
A radio unit connected to each antenna element, converting a received signal to a baseband signal at the time of reception, outputting to a channel information acquisition circuit, and transmitting a transmission signal from the antenna element as a radio signal at the time of transmission;
A channel information acquisition circuit that estimates channel information for a communication partner from a signal input from the wireless unit and outputs the channel information to a transmission space vector arithmetic circuit;
A transmission space vector arithmetic circuit for calculating a transmission space vector group based on the channel information input from the channel information circuit;
From the transmission space vector group input from the transmission space vector arithmetic circuit, the product of the attenuation amount of the signal power generated when combining communication partners ,

Or

(A ₁ , A ₂ : values obtained by integrating the attenuation amounts of the first and second communication partners. Mu ′ (l): number of communication partners, I: unit matrix, V ₁ : first Right singular matrix of channel response matrix of communication partner, V ′ ₁ , V ′ ₂ : first, and column vector group corresponding to eigenvalues among right singular matrix of channel response matrix of second communication partner, H: Conjugate complex matrix)
And a signal degradation amount estimation circuit that outputs to the communication partner selection circuit, and
Based on the product of the attenuation amount input from the signal degradation amount estimation circuit selects the communication partner, and the communication party selection circuit for outputting a communication partner selected in transmission weight calculating circuit,
The channel information of the selected communication partner is acquired from the channel information acquisition circuit, a transmission weight and a transmission mode including a modulation scheme, a coding rate, and an interleaving method are determined, and a data division circuit and a transmission signal conversion circuit A transmission weight calculation circuit to output to
A data dividing circuit for dividing the transmission data into the number of communication sequences according to the modulation method;
A modulation circuit that modulates the transmission data divided into the signal series;
A transmission signal conversion circuit that multiplies the modulated transmission data by a transmission weight determined by the transmission weight calculation circuit and outputs the result to the radio unit connected to the corresponding antenna element;
A wireless communication apparatus comprising: The communication partner selection circuit is:
Based on the product of the attenuation amount input from the signal deterioration estimating circuit determines a communication partner, and outputs the communication partner selected on the transmission weight computation circuit,
The transmission weight calculation circuit includes:
The transmission quality of the formed signal path is estimated, the transmission mode including the modulation scheme, coding rate, and interleaving method is estimated, and output to the data division circuit, the modulation circuit, and the transmission signal conversion circuit. 3. The wireless communication device according to 3.

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