Efficient detection for space-frequency OFDM transmit diversity scheme

In this paper we propose two efficient symbol detection algorithms for space-frequency OFDM (SF-OFDM) transmit diversity scheme. When the number of subcarriers in the SF-OFDM scheme is small, interference between adjacent subcarriers is generated. The proposed algorithms eliminate this interference in parallel or sequential manner and obtain a considerable performance improvement over the conventional detection algorithm. The bit-error rate (BER) performance of the proposed detection algorithms was evaluated by the simulation. In the case of 2 transmit and 2 receive antennas, at BER=10^-4 the proposed algorithms obtain about 3 dB gain. In the results of logic synthesis using 0.35 μm CMOS technology, the proposed SF-OFDM-PIC and SF-OFDM-SIC symbol detectors are composed of 28K and 26K logic gates, respectively. Since the proposed algorithms cancel the interference caused by the small number of subcarriers and provide an excellent diversity advantage the SF-OFDM scheme with the proposed algorithms can be a good solution for systems with a small number of subcarriers such as wireless LAN.