A method and system for performing Maximum Likelihood Detector (MLD) preprocessing in a Multiple-Input Multiple-Output (MIMO) communication system, the method including, obtaining a received signal Y a corresponding channel matrix H and a vector of noise samples n; calculating a whitening filter L.sup.−H; whitening a channel matrix H; selecting one of a first calculation or a second calculation, based on estimated complexity of the calculations; and performing preprocessing of the received signal using the selected calculation. The first calculation includes: whitening the received signal and performing a Cordic based QR decomposition to the whitened channel matrix {tilde over (H)} and the whitened received signal {tilde over (Y)} to obtain triangular matrix R and Y=Q.sup.HL.sup.−HY. The second calculation includes: performing a Cordic based QR decomposition to the whitened channel matrix {tilde over (H)} and the whitening filter L.sup.−H to obtain triangular matrix R and Q.sup.HL.sup.−H, and multiplying the received signal Y by Q.sup.HL.sup.−H to obtain Y=Q.sup.HL.sup.−HY.

Embodiments of this application disclose a channel estimation method and apparatus, and relate to the field of communications technologies, to help reduce indication overheads. The method may include: generating and sending indication information, where the indication information is used to indicate M N-dimensional precoding vectors, each precoding vector is applied to one of M frequency bands, the M N-dimensional precoding vectors form a space-frequency matrix, and the space-frequency matrix is generated by performing weighted combination on a plurality of space-frequency component matrices, where the space-frequency matrix is an M×N-dimensional space-frequency vector or an X×Y space-frequency matrix, X and Y are one and the other of M and N, M≥1, N≥2, and both M and N are integers.

Embodiments of this application disclose a channel estimation method and apparatus, and relate to the field of communications technologies, to help reduce indication overheads. The method may include: generating and sending indication information, where the indication information is used to indicate M N-dimensional precoding vectors, each precoding vector is applied to one of M frequency bands, the M N-dimensional precoding vectors form a space-frequency matrix, and the space-frequency matrix is generated by performing weighted combination on a plurality of space-frequency component matrices, where the space-frequency matrix is an M×N-dimensional space-frequency vector or an X×Y space-frequency matrix, X and Y are one and the other of M and N, M≥1, N≥2, and both M and N are integers.

Embodiments of this application provide a channel estimation method and apparatus, and relate to the field of communications technologies, to help reduce indication overheads. The method includes: generating and sending indication information, where the indication information is used to indicate M N-dimensional precoding vectors, each precoding vector is applied to one of M frequency bands, the M N-dimensional precoding vectors form a space-frequency matrix, and the space-frequency matrix is generated by performing weighted combination on a plurality of space-frequency component matrices, where the space-frequency matrix is an M×N-dimensional space-frequency vector or an X×Y space-frequency matrix, X and Y are one and the other of M and N, M≥1, N≥2, and both M and N are integers.

The present disclosure proposes a method, a network element, and a non-transitory computer readable storage medium for scheduling a user equipment (UE) for transmission. The method comprises: determining, for the UE, a first downlink channel status at a first time point and a second downlink channel status at a second time point which is later than the first time point, respectively, determining, for the UE, a temporal coherence between the first downlink channel status and the second downlink channel status; and scheduling the UE based on the determined temporal coherence.

An apparatus includes a first communication device with multiple antennas, operably coupled to a processor and configured to access a codebook of transformation matrices. The processor generates a set of symbols based on an incoming data, and applies a permutation to each of the symbols to produce a set of permuted symbols. The processor transforms each of the permuted symbols based on at least one primitive transformation matrix, to produce a set of transformed symbols. The processor applies, to each of the transformed symbols, a precode matrix selected from the codebook of transformation matrices to produce a set of precoded symbols. The codebook of transformation matrices is accessible to a second communication device. The processor sends a signal to cause transmission, to the second communication device, of multiple signals, each representing a precoded symbol from the set of precoded symbols, each of the signals transmitted using a unique antenna from the plurality of antennas.

Provided are a QR decomposition-based detection method and apparatus based on overlapped multiplexing. The QR decomposition-based detection method includes: step S1: obtaining a receive sequence, where the receive sequence is a sequence obtained by encoding and modulating an input signal based on a multiplexing waveform matrix and transmitting the signal through a Gaussian channel; and step S2: detecting the receive sequence by using a QR decomposition algorithm, where step S2 includes: decomposing a foreknown multiplexing waveform matrix into a unitary matrix and an upper triangular matrix; performing matrix multiplication processing on the receive sequence based on the unitary matrix, to obtain a data sequence; and performing layer-by-layer detection on the data sequence based on the data sequence, the upper triangular matrix, and a quantized decision factor.

Apparatuses, systems, and techniques to perform signal processing operations in a fifth generation (“5G”) radio signal. In at least one embodiment, one or more processors equalize, in parallel, one or more 5G radio signals.

Embodiments of this application disclose a channel estimation method and apparatus, and relate to the field of communications technologies, to help reduce indication overheads. The method may include: generating and sending indication information, where the indication information is used to indicate M N-dimensional precoding vectors, each precoding vector is applied to one of M frequency bands, the M N-dimensional precoding vectors form a space-frequency matrix, and the space-frequency matrix is generated by performing weighted combination on a plurality of space-frequency component matrices, where the space-frequency matrix is an M×N-dimensional space-frequency vector or an X×Y space-frequency matrix, X and Y are one and the other of M and N, M≥1, N≥2, and both M and N are integers.

An apparatus includes a first communication device with multiple antennas, operably coupled to a processor and configured to access a codebook of transformation matrices. The processor generates a set of symbols based on an incoming data, and applies a permutation to each of the symbols to produce a set of permuted symbols. The processor transforms each of the permuted symbols based on at least one primitive transformation matrix, to produce a set of transformed symbols. The processor applies, to each of the transformed symbols, a precode matrix selected from the codebook of transformation matrices to produce a set of precoded symbols. The codebook of transformation matrices is accessible to a second communication device. The processor sends a signal to cause transmission, to the second communication device, of multiple signals, each representing a precoded symbol from the set of precoded symbols, each of the signals transmitted using a unique antenna from the plurality of antennas.