A method for improving the performance of successive cancellation in mobile spread MIMO OFDM

Bell Labs layered space-time (BLAST) promises to increase greatly the capacity of future broadband mobile communications. However, in MIMO communication systems, the decoded BER performance of successive cancellation receivers is limited by the performance of the stream with the highest mean squared error. The paper presents a novel method to determine the different power weighting to be applied by the transmitter to each BLAST data stream in frequency-selective communications to improve the performance of a successive cancellation receiver. In addition, the new method predetermines the successive cancellation decoding order, thus simplifying the receiver. Simulation results for a spread OFDM system show up to a 5.0 dB improvement in frequency-selective channels over BLAST with equal power on each stream.