Abstract: A multiuser space-time coding system combined with the Turbo-BLAST scheme is presented. Since the conventional iterative receiver with symbol-level cancellation (SLC) has high computation complexity, a low complexity iterative receiver scheme with bit-level cancellation (BLC) and detection is proposed which can perform bit-level cancellation by decomposing an M-QAM constellation into a linear combination of binary constellations. Theoretical analysis and simulation results show that the proposed scheme has lower complexity compared with the conventional receiver without introducing performance degradation, while the spectral efficiency is improved due to the BLAST structure used at the transmitter.

Key words:

space-time coding, Turbo-BLAST, iterative receiver, soft interference cancellation, bit-level cancellation