Low Complexity Adaptive Group Detection in Layered Space-Time MIMO Wireless Communications

It discusses the detection techniques of the LAST (also known as the vertical Bell Laboratories layered space-time (V-BLAST) scheme) for both single user (SU) and multiuser(MU) MIMO wireless communication systems. To strike a better tradeoff between computational complexity and performance, a simple, yet effective group detection with adaptive group order successive interference cancellation (AGOSIC) is addressed. The new approach sequentially peels off the detected signals group by group in a descending order of power levels, and, most noticeable, the number of users in each group are adaptively determined based on the average of the post signal to noise ratio (SNR) to achieve a better ordering of signals. More specifically, according to the threshold, which is stage dependent, the remaining signals in each stage are partitioned into two groups: the desired group and the residual group. After conducting the layered space-time processing scheme, the signals in the desired group, whose SNRs are all greater than or equal to the threshold, are then removed. The whole process is repeated until all users are detected. The new scheme can suppress the effect of multiple access interference (MAI) in the MU-MIMO, and adaptively mitigate the effect of multiple access interferences (MSI) in both SU-MIMO and MU-MIMO. Simulations show that proposed scheme in both scenarios can yield close and sometime even better than, bit error rate (BER) performance as that of the previous works, but with substantially reduced complexity and latency