94 results about "Conjugate transpose" patented technology

The invention discloses a MIMO pre-coding method with a plurality of subchannels and a pre-coding signal receiving method; in a sender and a receiver, m pre-coding vectors which are the same with that of the receiver are determined in a predefined code book for constructing an original pre-coding matrix V, wherein, m is the number of the subchannels; the Givens angles between two subchannels in the subchannels are acquired, and a Givens pre-coding matrix G is constructed according to all the required Givens angles. The sender uses the product of the original pre-coding matrix V and the Givenspre-coding matrix G as a sending pre-coding matrix and sends signals by using the sending pre-coding matrix; the receiver uses a conjugate transpose matrix of the product of a signal channel matrix H, the original pre-coding matrix V and the Givens pre-coding matrix G as a receiving weight matrix and implements signal receiving and detecting by using the receiving weight matrix. The method of theinvention can greatly reduce the interference among subchannels and improve system performance.

The invention discloses a low-complexity hybrid precoding method in a millimeter wave large-scale MIMO system. In the method, the minimum F norm is got between corresponding positions of a precoding scheme corresponding to each radio frequency link and partially connected with a hybrid precoding scheme and an optimal digital precoding scheme under the condition of not considering the radio frequency link, and thus a digital precoding matrix and an analog precoding matrix of each radio frequency link are got via computation. The phase of the analog precoding matrix of each radio frequency linkis the phase of a maximum singular value vector of the optimal digital precoding matrix, the real part of a digital precoding matrix element is the product of conjugate transpose of the analog precoding matrix and the real part of an optimal digital precoding vector at a corresponding position, and the imaginary part of the digital precoding matrix element is the product of the conjugate transposeof the analog precoding matrix and the opposite number of the imaginary part of the optimal digital precoding vector at the corresponding position. Compared with analog precoding, the method providedby the invention can acquire the higher system accessibility and speed with the lower algorithm complexity.

A receiver includes a channel estimator for estimating a channel impulse response of a radio channel; an equalizer for generating linear minimum mean-square error equalizer coefficients and providing an equalized signal to a correlator; an estimating unit for forming an initial estimate of received data elements on the basis of an equalized signal; and a processing unit. The processing unit is configured to calculate a scaling factor by taking an inverse value, subtracted from a value of one, of a conjugate transpose of a linear minimum mean-square error equalizer coefficient vector multiplied by a channel impulse response vector, and to use the scaling factor for determining reliability of the initial estimate of the received data elements.

This invention provides a multi-user and multi-antenna communication method including: at the base station, carrying out geometrical mean analysis to the channel matrix to get a back filter matrix Q, an up triangle matrix R and a pre-coding matrix P, carrying out linear pre-coding to data emitted to users from the base station by matrix P, utilizing the multiplex conjugate transposed matrix QH of Q to transform the emission signals after pre-code in linearity, utilizing the coefficients in R corresponding to the users to eliminate signal interference among users in the emitted signals to be emitted to the channels and feeding back the QH of the Q to the user ends to be used to carry out linear transformation to the received signals at the receiving end.

A method and apparatus for increasing in the data rate of a multiple-input and/or multiple-output system that has frequency selective fading by using training sequences with both low normalized auto-correlation and low normalized cross-correlation. Both 1) the sum of the square of the normalized auto-correlation of each training sequence over an auto-correlation window and 2) the sum of the square of the normalized cross-correlation of each pair of the training sequences over a cross-correlation window, are significantly less than unity. In one embodiment of the invention the training sequences are shifted versions of each other, and the low normalized cyclic-auto-correlation of cyclic sequences is significantly less than unity, with each cyclic sequence being N′, N′=N−L+1, symbols of one of the at least two training sequences. In another embodiment, the training sequences are ones where the trace of the inverse of the product of the matrix of training sequences' symbols and the conjugate transpose of this matrix is low. The matrix is a function of the number of symbols over which multipaths of significant power can arrive, the number of training sequences, and the number of symbols in a training sequence. More particularly the matrix is a block-toeplitzmatrix composed of the training symbols.

The invention relates to a quick implementation method for passive radar range migration compensation and belongs to the technical field of radar target detection. The method comprises the following steps: (1) a direct wave signal and an echo signal received by a passive radar antenna are segmented and rearranged into two-dimensional matrices; (2) each row of the direct wave and the echo wave is transformed to the frequency domain; (3) the transformed direct wave matrix is multiplied by the conjugate transpose of the transformed echo wave matrix; (4) each row is extracted after being processed by a low-pass filter; (5) each column is subjected to CZT; and (6) each row is transformed to the time domain, and a cross-ambiguity function result subjected to migration compensation is obtained. Compared with a conventional range migration compensation method based on CZT and IFFT to achieve keystone transform, the provided method reduces operation steps and the amount of computation substantially while the gain accumulated is almost the same.

The invention discloses a BD (block diagonalization) pre-coding method and device, wherein the method comprises the following steps: determining a total user channel matrix Hs according to a downlink channel matrix of each user in a system; carrying out QR factorization on a conjugate transpose matrix of the total user channel matrix Hs to obtain a product of an orthogonal matrix Q and an upper triangular matrix R, and expressing the total user channel matrix Hs as the product of a lower triangular matrix L and a conjugate transpose matrix QH of the orthogonal matrix Q; carrying out inverse calculation on the lower triangular matrix L to obtain L-1; according to the inversed L-1 of the lower triangular matrix L and the orthogonal matrix Q, obtaining a null space orthogonal basis of an interference channel matrix of each user; according to the null space orthogonal basis of the interference channel matrix of each user, constructing a linear pre-coding matrix of each user; and carrying out linear pre-coding on a transmitting signal of each user by utilizing the constructed linear pre-coding matrix. The technical scheme disclosed by the invention can reduce the system complexity and improve the coding efficiency.

The invention provides a method and a device for eliminating intercell interference in a multi-cell MIMO wireless communication network. In the method, a mobile terminal selects data stream fluxion transmitted by a service base station according to a downlink physical channel transmission matrix, generates a filtration matrix based on the matrix and the fluxion, carries out precoding processing on detection signals by using a conjugate transpose matrix of the filtration matrix, and then transmits the detection signals to the service base station and an interference base station; and the service base station receives the detection signals from the mobile terminal and the detection signals from the interfered mobile terminal, estimates a downlink equivalent channel transmission matrix from the base station to a serviced mobile terminal and a downlink equivalent channel transmission matrix from the base station to the interfered mobile terminal; generates a precoding matrix based on a predetermined rule, and then carries out precoding process the signals to be transmitted with the matrix and transmits the signals to the serviced mobile terminal. The invention can improve the performance for interference elimination and reduces expense of detection signals without extra signalling expense.

The invention provides a filter bank multicarrier modulation system and a design method thereof. According to the design requirement of the system, a prototype filter is determined, the prototype filter shifts on an angular frequency axis to obtain an integrated filter bank of a sending terminal, and an analysis filter bank of a receiving terminal satisfies a time domain complete reconstruction condition. Compared with the traditional frequency domain design, according to the system and method, a constraint condition that an integrated filter bank is the conjugate transpose of an analysis filter bank in the traditional filter bank multicarrier modulator is abandoned, and the integrated filter bank can be freely designed according to the design requirement of the system. According to the multicarrier modulator in the invention, while the reconstruction condition is completely satisfied, the modulator still has a very high frequency resolution and is especially suitable for being applied in a communication system with a strict frequency resolution requirement.

The invention discloses a data processing device. The data processing device is used for solving a lower triangular matrix L corresponding to an n*n symmetric positive definite matrix R, wherein the R is equal to LDLH, the D is a diagonal matrix, the LH is a conjugate transpose matrix of the L, and the n is an integer larger than or equal to 2. The data processing device comprises a multiplying unit, an accumulator and a summator. The input end of the data processing device is connected with the input end of the multiplying unit, the output end of the multiplying unit is connected with the input end of the accumulator, the output end of the accumulator is connected with the output end of the summator, the input end of the data processing device is also connected with the input end of the summator, the output end of the summator is used for outputting matrix data to a storage device, and the output end of the multiplying unit is also used for outputting matrix data to the storage device. By means of the data processing device, the symmetric positive definite matrix can be decomposed without a large amount of root extraction operation, operation complexity is lowered, and logical operation resources are saved.

The invention discloses a hardware framework for matrix inversion in large-scale MIMO linear detection. The hardware framework comprises a pre-computation module and a matrix inversion sub-module, wherein the pre-computation module comprises a lower triangular pulse multiplier, an adder, a conjugate transpose module, a reciprocal module, a negation module and a vector multiplier, the lower triangular pulse multiplier is respectively connected with the adder and the conjugate transpose module, the adder is connected with the vector multiplier through the reciprocal module and the negation module sequentially, the conjugate transpose module is connected with the vector multiplier, the matrix inversion sub-module is of an IIR filter structure, and the vector multiplier and the reciprocal module are respectively connected with the matrix inversion sub-module. The invention further provides a method for matrix inversion in large-scale MIMO linear detection. By the hardware framework and the method, computation complexity and hardware cost are lowered greatly, optional precision accuracy can be obtained by iterative computation, high flexibility is provided, extra hardware cost is avoided, and good compatibility is achieved.

The invention discloses a multi-user downlink transmission method based on the spatial modulation of a receiving end, for mainly solving the problem that in a multi-user downlink communication system, a base station needs to transmit information to multiple users of a cell at the same time. The method comprises the steps of solving a pre-coding matrix by a base station in a conjugate transpose matrix manner; performing spatial modulation based on the receiving end on transmitted information and performing perturbation on the obtained information, and then multiplying by the pre-coding matrix to obtain the modulated information; then broadcasting the modulated information to K users by the base station; and at last demodulating the modulated information transmitted by the base station by the K users through maximum likelihood, and thereby completing downlink transmission. The multi-user downlink transmission method based on the spatial modulation of the receiving end has the advantages of being low in computing complexity, simple in design of the receiving end, and capable of obtaining greater bit error rate performance gain, and is particularly applicable to the multi-user MIMO system when the quantity of transmission antennas configured by the base station is large.

The invention discloses a precoding treatment method for a multi-input multi-output (MIMO) broadcast channel, and a precoding treatment device and a base station thereof. The method comprises the following steps: utilizing a unit matrix as a decoding matrix of a receiver o obtain a receiver initial decoding matrix; calculating an initial precoding emission matrix corresponding to each user data stream according to the receiver initial decoding matrix and the minimum mean square error standard; utilizing the multiplication of an emission channel matrix and the initial precoding emission matrix as an equivalent channel corresponding to the user, and performing the singular-value decomposition of the equivalent channel corresponding to the user and then selecting a right eigenvector with the maximum eigenvalue from the decomposition results; utilizing the multiplication of the initial precoding emission matrix and the conjugate transpose of the right eigenvector as a first precoding emission matrix; performing the iterative calculation of the final precoding emission matrix and the decoding matrix of the receiver by utilizing the first precoding emission matrix until the preset condition comes into existence. The precoding treatment method increases the convergence rate of calculating the precoding emission matrix and the receiver decoding matrix.

The invention discloses a sphere-decoding detection method with fixed complexity, comprising the following steps: carrying out channel extension on channel matrixes of acquired received signals based on minimum mean squared error (MMSE) criterion to obtain extended channel matrixes; carrying out sequenced QR decomposition on the extended channel matrixes to obtain a group of displacement series as well as unitary matrixes and ordered upper triangular matrixes of elements on diagonal lines; multiplying the conjugate transpose of the unitary matrixes by the received signals to obtain received vectors; setting a parameter P and a parameter Mk (k is equal to 1, 2...P), starting from a last layer, and detecting the processed received signals layer by layer from back to front so as to generate a plurality of survivor paths in accordance with the formula in the specification; and outputting a path with the minimum Euclidean distance as a detection result from the plurality of survivor paths after all layers are detected. By using the sphere-decoding detection method, the complexity of the sphere-decoding detection can be reduced effectively at the same time of ensuring the system performances under the condition of high-order modulation (HOM) and high-dimension antenna configuration.

The invention provides a target detection method based on two-dimensional sliding window robust space-time self-adaptive processing, which can increase the accuracy of target detection. The target detection method comprises the steps of : step 1, receiving echo data through an airborne radar; step 2, carrying out space-time sliding window processing on the echo data; step 3, establishing a target apparent steering vector error boundary matrix; step 4, calculating an autocorrelation matrix of projectional component of the echo data after space-time sliding window processing on an orthogonal complementary space of a subspace formed by the target; step 5, calculating a correlation matrix after diagonal loading of the autocorrelation matrix; step 6, solving a weight vector; step 7, judging whether a module value of a column vector obtained through multiplying a conjugate transpose matrix of the boundary matrix by the weight vector is less than 1, if so, increasing loading factors and then executing step 5 and step 6, otherwise, regarding the weight vector as the optimal weight vector; and step 8, constructing a filter by utilizing the optimal weight vector so as to filter the echo data after space-time sliding window processing, and acquiring target echo data.

The invention relates to the technical field of communication, in particular to a wireless receiving system and a method and a device for channel estimation so as to obtain better noise reducing effect for channel estimation. The method provided by the invention comprises the following steps: extracting a channel estimation result without a virtual carrier component from initial channel estimation results; transforming the channel estimation result without the virtual carrier component to obtain a first transformation result with the conjugate transpose matrix of a decomposed matrix of a partial frequency domain transformation matrix, wherein the first transformation result does not comprises an interference component or a noise component; and transforming the first transformation result with the decomposed matrix to obtain a final channel estimation result. The invention adopts matrix transformation in the channel estimation, and fully considers the influence of the virtual carrier on the noise reduction technology for channel estimation. According to the simulation results, compared with the prior art, the invention has better noise reducing effect and facilitates the engineering practice.

The invention relates to a low complexity orthogonal iterative beam forming method. The method comprises the following steps that: step 1, initialization operation is carried out on a matrix V^K to obtain an initialization value V^0 that is equal to I M*J, wherein the following relation is satisfied: V^< ' >0*V^0=IJ*J and the V^< ' >0 expresses a conjugate transpose matrix of the matrix V^0; step 2, a transmitting terminal transmits V^<*>k-1 and a receiving terminal receives an r, wherein the r satisfies the following relation: r=HV^<*>k-1; step 3, the receiving terminal sends r<*> that expresses a conjugate matrix of the r; and under a time division duplex (TDD) mode, due to channel reciprocity, a reverse channel matrix H(S) is a transposed matrix H<T> of a forward channel matrix H, that is, H(S) is equal to H<T>; and a signal matrix t received by the transmitting terminal satisfies the following relation: t=H(S)R<*>=H<T>r<*>=H<T>H<*>V^k-1, wherein the H<*> is a conjugate matrix of the H; step 4, QR matrix decomposition is carried out at the transmitting terminal; step 5, if a cyclic variable k is greater than or is equal to Niteration, a V that is equal to V^<*>k-1 is output as a beam forming matrix V of the transmitting terminal; and step 6, the transmitting terminal sends the beam forming matrix V and the receiving terminal receives an r that is equal to a result by multiplying an H by a V, and QR matrix decomposition is carried out. According to the invention, beneficial effects are as follows: the system performance can be ensured and algorithm complexity can be substantially reduced.

The invention discloses an MIMO (Multiple Input Multiple Output) signal detection method and a detector on the basis of a K-Best algorithm. The method comprises the following steps of: according to an antenna number and a modulation mode which are designated by a user, configuring a detection layer number; acquiring a product of an upper triangular matrix R of a channel transfer matrix H, which is subjected to QR decomposition, and a conjugate transpose matrix of a unitary matrix and a receiving vector y; expanding all constellation points on a p=Mth layer and PC (Fiber Channel) paths on a p=M-1th layer in parallel and generating two groups of candidate paths in an interweaving mode to carry out parallel processing; expanding the candidate paths in a parallel mode as required to find out K survivor paths and K-2 abandon paths on a pth layer; processing the survivor paths on each detection layer to obtain survivor path outputs and carrying out reusing processing on the abandon paths; and carrying out log-likelihood processing on the K survivor paths and the K-2 abandon paths. The invention can solve the problems of low throughput, poor flexibility, poor detection performance, difficulty in implementing a hardware structure and the like.

The invention provides a sphere decoding detection method based on an ultra large scale integrated circuit, comprising the following steps of: A. carrying out QR decomposition to a channel matrix; B. multiplying conjugate transpose of a Q matrix and received signals to obtain an equalizing signal Rho; C. setting the searching node number Ki of an ith layer; D. determining sphere decoding expression according to an R matrix and Rho, carrying out table-looking-up sequencing to the nodes of the 1st layer and reserving K1 of nodes with minimum Euclidean distances; E. respectively executing searching of the ith layer, carrying out table-looking-up sequencing in nodes according to the sphere decoding expression to the Ki-1 of nodes reserved by the ith-1st layer, calculating weights of subnodes of the Ki-1 of nodes, then carrying out divide-and-conquer sequencing to subnodes of the Ki-1 of nodes by adopting VLSI according to the result of table-looking-up sequencing and reserving Ki of nodes with minimum weights; and F. outputting decoding result when searching the last layer. The sphere decoding detection method can effectively reduce the operation complexity of sphere decoding.

The invention discloses a self-interference suppression method based on block diagonalization and triangular decomposition. The implementation steps are as follows: at first, obtaining a channel matrix of each user, the block diagonalization algorithm is used to obtain the first layer precoding matrix of each user, multiplying the first layer precoding matrix of each user by the channel matrix ofthe corresponding user, the second layer precoding matrix of each user is obtained by triangular decomposition and singular value decomposition of the equivalent channel matrix of each user. Finally,the conjugate transpose matrix of the left unitary matrix of the lower triangular matrix of each user is used as the reception decoding matrix of each user. The second layer precoding matrix of each user is obtained by triangular decomposition and singular value decomposition. The invention can eliminate the interference between users, restrain the interference of multiple antennas of the users themselves, improve the transmission rate of the system users and improve the transmission performance of the system downlink.

The invention discloses a Bi-CGSTAB and SL0 algorithm-based MIMO radar target parameter estimation method and belongs to the MIMO radar target estimation technical field. According to the method, a pseudo-inverse substitution matrix which is represented by a character described in the descriptions of the invention, which is obtained by off-line calculation in an SL0 algorithm, is adopted to replace the pseudo-inverse A<*>(AA<*>)<-1> of a sensing ill-conditioned matrix A, wherein (.)<*> indicates the conjugate transpose operation of the matrix, an improved SL0 algorithm is adapted to process the received signals y of an MIMO radar. Thus, the failure of the SL0 algorithm caused by the ill condition of the sensing ill-conditioned matrix of that the MIMO radar can be avoided, and the robustness of the SL0 algorithm can be improved, so that the SL0 algorithm can have high reconstruction precision; the pseudo-inverse substitution matrix of the sensing ill-conditioned matrix of the MIMO radar is calculated offline and is stored; and when the SL0 algorithm is utilized to estimate the target parameters of the MIMO radar, the value of the pseudo-inverse matrix can be directly called, and therefore, the solution time of an ill-conditioned linear equation set is saved, the reconstruction speed of sparse target signals is accelerated, and the real-time performance of the target parameter estimation of the MIMO radar is improved.

The invention discloses a method for eliminating spatial correlation of a transmitting end channel. The method comprises the following steps that: a receiving end selects a good laboratory practice (GLP) codebook which has the maximum signal to interference plus noise ratio index and serves as a hierarchical structure codebook from a receiving end codebook library according to channel state information; the receiving end feeds a sequence number of the hierarchical structure codebook in the receiving end codebook library back to a transmitting end; the transmitting end selects a GLP codebook from a transmitting end codebook according to the sequence number of the codebook; and the transmitting end calculates the covariance matrix of a transmitting signal to be transmitted and standardizing the product of the extraction of a conjugate transpose of the covariance matrix of the transmitted signal and the GLP codebook so as to construct a new codebook. The codebook constructed by the method can eliminate the spatial correlation of the transmitting end channel, so that the transmitting end can pre-code without being influenced by the spatial correlation of the transmitting end channel. Moreover, in the method, when the receiving end feeds the sequence number of the codebook back to the transmitting end, an increment feedback mechanism is introduced, so that feedback overhead is reduced.

The invention provides a precoding method and a matrix generating device of a CoMP (coordinated multi-point) multiple-user MIMO (multiple-input multi output) system. The method comprises the following steps that: S1, a central control station acquires base station transmitting power Pn (n=1,...,K), channel information Hn,i between a base station n and a user i and the signal-to-noise ratio SNRn,i (i=1,...K) from each cell base station n (n=1,...T) and further obtains the channel information Hi and noise power of each user, wherein T is the number of coordinated cells and K is the number of users in the system; S2, the central control station acquires a complementary channel of each user according to the channel information Hi of each user and carries out channel expansion on each complementary channel to obtain a matrix shown in the specification, wherein I is a unit matrix shown in the specification and Mk represents the number of receiving antennae of a user k; S3, the central control station carries out LQ (leadership quotient) decomposition on the matrix to obtain a unitary matrix Q1; S4, the central control station carries out conjugate transpose on the submatrix of the Qi and multiplies the submatrix subjected to conjugate transpose by Hi, thus obtaining an equivalent channel of each user; S5, the central control station carries out SVD (singular value decomposition) on each equivalent channel so as to obtain a precoding matrix Wi (i=1,...,K) of each user; and S6, the central control station obtains the precoding matrix (n=1,...T) of each base station according to the precoding matrix Wi (i=1,...,K) of each user and transmits each precoding matrix (n=1,...T) to the corresponding cell base station to further carry out precoding.