Complexity reduction for lattice reduction aided detection in MIMO-OFDM systems

A Lattice reduction (LR) aided receiver for multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) systems can achieve near ML detector performance. However, Performing LR for each subcarrier can result in a large complexity. To deal with this problem, a low complexity scheme for lattice reduction (LR) aided detection in the MIMO OFDM system is presented. From exploiting frequency correlation among the neighboring channel matrix and the uni-modular transformation matrix of the preceding subcarrier, nearly LR reduced channel matrix is produced. Simulation results show that the proposed scheme can achieve the same performance with the conventional system while its complexity is significantly lower.