Partial FFT demodulation: A detection method for doppler distorted OFDM systems

Abstract

In mobile OFDM systems, such as underwater acoustic and digital video broadcasting (DVB) systems, time variation causes severe inter-carrier interference (ICI) which limits data detection performance. To address this problem, a signal processing strategy using several partial-interval FFTs instead of a conventional full-interval single FFT is proposed. Weighted combining of the partial FFT outputs coupled with standard OFDM processing, allows high performance symbol-by-symbol detection even in highly time-varying channels. Numerical examples show performance gains of several dB over a conventional receiver, thus indicating that an order of magnitude reduction in BER is achievable at a minimal increase in complexity.