An Efficient Algorithm Design of MIMO-OFDM Systems for Co-Channel Interference Mitigation

In this paper, we present an efficient algorithm of co-channel interference (CCI) mitigation for uplink multi-input multi-output orthogonal frequency division multiplexing (MIMO-OFDM) systems by exploiting the smoothness of OFDM channels in the frequency domain. Given the pilot sequences being synchronized, the proposed algorithm computes the time-domain equalizer by solving a high-dimensional block Toeplitz system, requiring no explicit estimation of the channels and interference-plus-noise covariance matrices (ICMs). We also present a technique to determine the order of equalizer, which is adaptive to the length of the time-domain finite-impulse-response (FIR) channel. The numerical experiments conducted on a fifth-generation (5G) new radio (NR) simulator show that the proposed algorithm outperforms the state-of-the-art schemes with even lower computational complexity.