Particle filtering detection in SFBC coded BLAST-OFDM systems

A method based on particle filtering for detection in SFBC-MIMO BLAST systems is proposed. The system achieves transmit diversity using space frequency block code and capacity enhancement through the V-BLAST architecture. In this paper we combine Alamouti's (1998) space frequency block code (SFBC), BLAST and OFDM to obtain transmit diversity and capacity enhancement in frequency selective fading channels. Since optimal ML detection is computationally prohibitive for higher order modulations and the complexity grows exponentially with the number of transmitting antennas we resort to the particle filtering approach. The particle filter (PF) exploits the MIMO-BLAST architecture and provides near-optimum performance. More importantly PF delivers a posteriori symbol probabilities and this information can be used to design an iterative (turbo) receiver to improve the BER performance. The PF demodulator and MAP channel decoder exchange the so called extrinsic information to successively improve the receiver performance.