FFT-Based Trellis Receiver for SEFDM Signals

Abstract

A new FFT-based trellis receiver for multicarrier signals with nonorthogonal frequency spacing (spectrally efficient frequency division multiplexing, SEFDM) is proposed. It is based on FFT and max-log-MAP algorithm, which is adapted to work with frequency samples of received signal. The iterative version of demodulator is also developed. The performance of proposed iterative QPSK-SEFDM demodulation is comparable with the one of classic coded QPSK modulation while the spectral efficiency remains very high. The proposed algorithms can demodulate SEFDM signals with large number of subcarriers.