Low-complexity soft-input soft-output detection based on EVD for MIMO systems

In this paper, we propose a low-complexity soft-input soft-output (SISO) detection algorithm for MIMO-OFDM systems, based on Eigen-Value decomposition (EVD), which using the real diagonal matrix inversion instead of the complex matrix inversion to reduce the complexity of the iterative receiver. The main objective of this paper is focused on the reduction of overall implementation complexity of the SISO detector based on the Minimum Mean Square Error(MMSE) criterion through three components: the Soft Modulation, the MMSE Equalizer and the Soft-Symbol Demapper. Simulation and complexity analysis results show that the proposed low-complexity SISO-MMSE detector achieves basically the same performance comparing with the classical SISO-MMSE detector, while providing a tremendous complexity reduction.