Constant Envelope OFDM in Multipath Rayleigh Fading Channels

Abstract

In this paper we consider the problem of equalizing constant envelope orthogonal frequency division multiplexing (CE-OFDM) signals that have been corrupted by frequency-selective multipath fading channels. A cyclic prefix guard interval is used to avoid interblock interference (IBI), and to make possible frequency-domain equalization (FDE) using the discrete Fourier transforms. It is shown that CE-OFDM exploits the multipath diversity of the channel due to frequency spreading of the data symbols. CE-OFDM compares favorably with conventional OFDM when the impact of nonlinear power amplification and power backoff is taken into account