On interference cancellation ordering of V-BLAST detectors

In this paper, the ordering effect of interference cancellation (IC) of V-BLAST detectors is evaluated in three different systems, which are the conventional V-BLAST system, the V-BLAST system with antenna selection, and the V-BLAST system with both antenna selection and adaptive modulation. The performance of different IC ordering algorithms, i.e. the optimal ordering algorithm and the fixed ordering algorithm, in these systems is compared through intensive simulations. It is shown that the performance of the optimal ordering, in terms of bit error rate and distribution of post-detection signal-to-noise ratio is superior to that of the fixed ordering algorithm in the conventional V-BLAST system, at cost of heavy computational load. The performance gap in terms of throughput becomes smaller when a simple antenna selection scheme is introduced in the V-BLAST system. In the system with both antenna selection and adaptive modulation, the effect of the ordering is not consistent and the throughput of the optimal ordering algorithm may sometimes even be worse than that of the fixed ordering algorithm.