Joint complex regularised zero‐forcing equalisation and CFO compensation for MIMO SC‐FDMA systems

Abstract

In single carrier frequency division multiple access (SC-FDMA) systems, frequency domain equalisers suffer performance degradation due to several channel impairments such as inter-symbol interference, inter-carrier interference (ICI), especially in multiple access/multiple input multiple output (MIMO) systems. This study presents a joint complex regularised zero forcing (JCRZF) equaliser that is able to compensate the channel impairments and to mitigate the ICI induced by the carrier frequency offset (CFO) in mobile channel environments. JCRZF equaliser is also able to eliminate the inter antenna interference resulting from the MIMO channel coupling by transforming the MIMO channel into equivalent SISO channels. Simulation results show that the JCRZF equaliser outperforms ZF based equalisers in terms of bit error rate while preserving their potential complexity and appropriate robustness to CFO estimation errors.