The Multi-Level Mapping Sequential Gaussian Approximation for MIMO Detection

This paper presents a low complexity detection scheme, based on sequential Gaussian Approximation, called multi-level mapping SGA detection, for multi-input multi-output wireless communication systems with high-order QAM modulation. In the SGA detection, only part of transmit symbol combinations contributing significantly to posterior probabilities are retained, having a complexity linear with retained branches number. Due to the property of high-order QAM formats, the new scheme calculates the sequence weight in step of two bits, resulting in a complexity reduction from exponential in the modulation order to linear, compared to basic SGA detection. Simulation results show that the multi-level mapping SGA can provide near the performance of the basic SGA detection