SIC and K-best LSD receiver implementation for a MIMO-OFDM system

Abstract

MIMO-OFDM receivers with horizontal encoding are considered in this paper. The successive interference cancellation (SIC) algorithm is compared to the K-best list sphere detector (LSD). The SIC and K-best LSD receivers are designed for a 2 × 2 antenna system with quadrature phase shift keying (QPSK), 16-quadrature amplitude modulation (QAM) and 64-QAM. The linear minimum mean squared error (LMMSE) based SIC detector cancels decoder outputs from the received signal. The performance of the SIC algorithm depends on the channel conditions. The SIC algorithm performs worse than maximum a posteriori probability (MAP) and the K-best list sphere detectors (LSD) when the MIMO streams are highly correlated but the SIC receiver performs better than the K-best LSD with less correlated streams. However, the latency of the K-best LSD is higher than that of the SIC receiver.