Diversity Effect of OFDM Communication with IQ Imbalance in the Rayleigh Fading Channel

Abstract

Orthogonal frequency division multiplexing (OFDM) has been used widely in several communication systems. However, OFDM is very sensitive to the radio frequency (RF) impairments. One of the serious major impairments is the IQ imbalance between In-phase (I) and Quadrature (Q) branches. This IQ imbalance can be the mail reason of bit error rate (BER) performance degradation in the high-speed OFDM communication system. In this paper, the closed form of BER of OFDM with IQ imbalance is derived in the Rayleigh fading channel and novelly investigates the effect of transmit and receive diversity on this OFDM communication system with Q imbalance in the Rayleigh fading channel. Via the computer simulation, it is verified that analytical result is very close to simulation result. So, it is very useful and convenient to evaluate the BER performance of multi-input multi-output (MIMO) system with IQ imbalance in the Rayleigh fading environment.