Joint iterative decoding and MMSE-SIC VBLAST detection of LDPC coded MIMO systems

Abstract

A joint iterative low-density parity-check (LDPC) decoding and minimum mean square error with successive interference cancel (MMSE-SIC) vertical-Bell laboratories layered space-time (VBLAST) detection of LDPC coded multiple input multiple output (MIMO) system is proposed in an additive white Gaussian noise (AWGN) channel. It combines the LDPC decoding with VBLAST detection into a unified iterative framework by integrity and united method. It adopts the joint iterative message processing through the VBALST detector and the variable and check nodes of LDPC decoder. So it reduces the unnecessary information loss, which usually happens in separated coding and detection MIMO systems. Simulation results show that the proposed joint LDPC coded binary phase shift keying (BPSK) MIMO schemes outperforms the contrast scheme of simple concatenation about 0.3~0.5 dB at a bit-error-ratio (BER) of 10-5 in an AWGN channel. In addition, it only requires some rational coding and detection complexity, because it employs the sparse check matrices for encoding and applies joint processing for detection too. Therefore, the proposed joint LDPC decoding and MMSE-SIC VBLAST detection of an LDPC coded MIMO system can be efficiently applied in modern wireless digital communications for high performance.