Multiuser detector for hybrid CDMA systems based on the Bareiss algorithm

At the base station in hybrid CDMA systems, multi-user detection (MUD) techniques are exploited to alleviate both multiple access (MAI) and inter-symbol (ISI) interference. MMSE MUD algorithms solve a linear problem where the system matrix has a block-Toeplitz shape. Sub-optimal algorithms with reduced complexity are mandatory to reduce the high computational load imposed by exact inversion techniques. However, when computational complexity is strongly reduced, sub-optimal algorithms may suffer performances degradation and severe near-far effects. In this paper, we introduce a new detector scheme that uses the block-Bareiss algorithm. This detector shows good performances and low computational power requirements, comparing favorably with simple implementations based on block-Fourier techniques. Simulations are presented and discussed for the specific TD-SCDMA application.