MIMO-OFDM Systems in the Presence of Phase Noise and Doubly Selective Fading

In this paper, we analyze the effects of phase noise to multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) systems over doubly selective Rayleigh fading channels. Similar to single-antenna OFDM, MIMO-OFDM suffers from significant performance degradation due to phase noise and time-selective fading, which causes inter- carrier interference (ICI). We derive the expressions of carrier- to-interference and signal-to-interference-plus-noise ratios. After characterizing the common phase error (CPE) caused by phase noise and ICI caused by phase noise, as well as time-selective fading, we then derive a minimum mean-squared error-based scheme to mitigate the effect of both phase noise and time-selective fading. We also evaluate and compare the performances of various detection schemes combined with the proposed CPE mitigation scheme. Through numerical results, we examine the relative performances and the potential error floors of these detection schemes.