A zero-forcing approximate log-likelihood receiver for MIMO bit-interleaved coded modulation

This letter considers multiple-input multiple-output (MIMO) systems with bit-interleaved coded modulation. An approximate log-likelihood decoding approach is presented based on a zero-forcing receiver. The implementation complexity is low compared to the maximum likelihood (ML) receiver. We show that the performance gap, compared to ML, reduces when either the number of receive antennas or the modulation order is increased. Results are presented for both narrowband fast-fading, and orthogonal frequency division multiplexing (OFDM) channels. In the OFDM case, we demonstrate performance gaps as low as 0.5 dB for MIMO extensions to the IEEE 802.11a wireless local area network physical layer standard.