Comparative analysis of ZF and MMSE detections for nakagami-m faded MIMO channels

In this paper, we studied the bit error rate (BER) for zero forcing (ZF) and minimum mean square error (MMSE) detection methods in spatially multiplexed multi-input-multi-output (SM-MIMO) systems over nakagami-m flat fading channels using binary phase shift keying (BPSK), quadrature phase shift keying (QPSK) and 16-ary phase shift keying (16-PSK) modulations. The coefficients of nakagami-m channel matrix has been generated from the gamma random variables (RVs). The analysis assumes that MIMO channels are limited by the Gaussian noise and receiver has complete knowledge of these channels. The results for spatially multiplexed MIMO system with two inputs two outputs with ZF and MMSE receivers for different values of fading parameter `m' and scale parameter `Ω' are illustrated using BER plots. Performance comparison of SM-MIMO system and single-input-multiple-output (SIMO) system is also presented in the results. Eye diagrams for received symbols after ZF and MMSE are also shown separately using 4-ary quadrature amplitude modulation (4-QAM).