Techniques for suppression of intercarrier interference in OFDM systems

This paper considers an OFDM system over frequency selective time-varying fading channels. The time variations of the channel during one OFDM frame destroy the orthogonality of different subcarriers and result in power leakage among the subcarriers, known as intercarrier interference (ICI), causing a degradation of system performance. In this paper, channel state information is used to minimize the degradation caused by ICI. A simple and efficient polynomial surface channel estimation technique is proposed to obtain the necessary channel state information. Based on the estimated channel information, we describe a MMSE based OFDM detection technique that reduces the degradation caused by ICI distortion. Performance comparisons between conventional OFDM and the proposed MMSE-based OFDM receiver structures under the same channel conditions are provided in this article. Simulation results of the system performance further confirm the effectiveness of the new technique over the conventional OFDM receiver in suppressing ICI in OFDM systems.