Abstract:

From the foundation of the investigation of the multi-user detection algorithm based on the subspace method, we propose a multiuser detection technology combined with array antennas reception—space-time multi-user detection technology to increase the capacity of the DS-CDMA system and improve the performance of the SNR and the bit error rate(BER). This technology makes it possible to apply multi-user detection to the overloaded system and increase the system capacity. The improved newOPAST algorithm is applicable to the blind space-time multi-user detector. Simulation results show that this scheme provides the output SNR and BER similar to those by the classic algorithm with stable global convergence and less computation complexity.

Key words: CDMA, multi-user detection, subspace tracking