PORT SELECTION WITH LOW COMPLEXITY

Systems and methods are disclosed for port selection for a wireless communication system. In one embodiment, a method performed by a Radio Access Network (RAN) node comprises dividing a channel matrix of one subcarrier of a Multiple-Input-Multiple-Output (MIMO) channel between an antenna array of the RAN node and a particular User Equipment (UE) into sub-matrices. The method further comprises forming a re-ordered channel matrix as a concatenation of the sub-matrices and forming a port-sorting matrix based on eigen vector matrices and eigen value matrices obtained via Eigen Value Decompositions (EVDs) performed on channel covariance matrices for the sub-matrices. The method further comprises applying the port-sorting matrix to the re-ordered channel matrix, re-ordering column vectors in the port-sorted channel matrix based on eigen values obtained from the EVDs, and applying grouping of the re-ordered, port-sorted channel matrix and port sorting accordingly to obtain a final port-sorted channel matrix.