Reduced-Rate OFDM Transmission with Statistics-Based ICI Mitigation

In this paper, we develop a general reduced-rate orthogonal frequency division multiplexing (OFDM) transmission scheme for inter-subchannel interference (ICI) mitigation in a high-mobility environment. By transmit and receive preprocessing, we transform the original N-subcarrier OFDM system into an equivalent K-subcarrier one with significantly reduced ICI. In particular, we develop a general structure of transmit and receive preprocessing matrices so that the K subchannels in the equivalent OFDM system share a common average signal-to-interference ratio (SIR). Without requiring the instantaneous channel state information, we optimize the preprocessing coefficients to maximize the SIR based on channel statistics. Numerical and simulation results demonstrate that the developed reduced-rate OFDM transmission achieves significant performance improvements over the existing ICI self-cancellation schemes.