Reduced-Rate OFDM Transmission With Statistics-Based ICI Mitigation
In this paper, the authors develop a general reduced-rate Orthogonal Frequency Division Multiplexing (OFDM) transmission scheme for Inter-sub-Channel Interference (ICI) mitigation in a high-mobility environment. By transmit and receive pre-processing, they transform the original OFDM system into an equivalent one with fewer sub-carriers and significantly reduced ICI. A general structure of transmit and receive pre-processing matrices is developed so that all sub-channels in the transformed OFDM system have a common average Signal-to-Interference Ratio (SIR). By utilizing channel statistics, they further optimize the pre-processing coefficients to maximize the SIR. Numerical and simulation results demonstrate that the proposed reduced-rate OFDM transmission achieves significant performance improvement over the existing ICI self-cancellation schemes.