Improving Performance and Detection Schemes of Mimo-Ofdm Systems in the Presence of Phase Noise and Doubly-Selective Fading Where Channel is Both Time and Frequency Selective

Abstract

MIMO-OFDM technology is a combination of multiple-input multiple-output (MIMO) wireless technology with orthogonal frequency division multiplexing (OFDM) that has been recognized as one of the most promising techniques to support high data rate and high performance in different channel conditions. In this paper we analyze the impacts of phase noise to multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) systems over doubly selective Rayleigh fading. Where channel is both time and frequency selective. Similar to single-antenna OFDM, Orthogonal frequency division multiplexing (OFDM) techniques have been investigated extensively to combat the effect of multipath delay. MIMO-OFDM suffers from significant performance degradation due to phase noise and time-selective fading, which causes intercarrier 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, using a minimum mean-squared error-based scheme to mitigate the effect of both phase noise and time-selective fading. Equally we evaluated and compared various detection schemes and their performances combined with the proposed CPE mitigation scheme. With numerical results, we examined the relative performances and the potential error floors of these detection schemes which show a total reduction of noise to 5%.