EURASIP Journal on Applied Signal Processing 
Volume 2004 (2004), Issue 10, Pages 1508-1519
doi:10.1155/S1110865704310139

Bandwidth Efficient OFDM Transmitter Diversity Techniques

King F. Lee1 and Douglas B. Williams2

 1Multimedia Architecture Lab, Motorola Labs, Schaumburg, 60196, IL, USA
2School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta 30332-0250, GA, USA
Received 17 December 2002; Revised 2 September 2003

Abstract

Space-time block-coded orthogonal frequency division multiplexing (OFDM) transmitter diversity techniques have been shown to be efficient means of achieving near-optimal diversity gain in frequency-selective fading channels. However, these known techniques all require a cyclic prefix to be added to the transmitted symbols, resulting in bandwidth expansion. In this paper, iterative space-time and space-frequency block-coded OFDM transmitter diversity techniques are proposed that exploit spatial diversity to improve spectral efficiency by eliminating the need for a cyclic prefix.