Constant Envelope OFDM

This paper describes a transformation technique aimed at solving the peak-to-average power ratio (PAPR) problem associated with OFDM (orthogonal frequency-division multiplexing). Constant envelope OFDM (CE-OFDM) transforms the OFDM signal, by way of phase modulation, to a signal designed for efficient power amplification. At the receiver, the inverse transformation--phase demodulation--is applied prior to the conventional OFDM demodulator. The performance of CE-OFDM is analyzed in additive white Gaussian noise (AWGN) and fading channels. CE-OFDM is shown to achieve good performance in dense multipath with the use of cyclic prefix transmission in conjunction with a frequencydomain equalizer (FDE). By way of computer simulation and hardware realization, CE-OFDM is shown to compare favorably to conventional OFDM.

• Type: Journal
• Year: 2008
• Where: TCOM
• Authors: Steve C. Thompson, Ahsen U. Ahmed, John G. Proakis, James R. Zeidler, Michael J. Geile
• Keywords: Constant Envelope Ofdm, Conventional Ofdm, OFDM, TCOM 2008