A New Block-Wise Adaptive Bit and Power Allocation Algorithm in V-BLAST System

摘要

Block-wise adaptive bit and power allocation in V-BLAST system with a target BER and a total transmit power constraint is discussed in this paper. While block-wise allocation scheme greatly reduces feedback overhead, its BER performance suffers from time-variance of channel and error propagation in V-BLAST detection. We analyze the BER performance of the block-wise adaptive V-BLAST system with different kinds of SIC ordering over time-varying channel and find the optimal SIC ordering scheme. In order to reduce the impact of error propagation, a new bit and power allocation algorithm based on error propagation compensation is proposed in this paper. Simulation results show, the new algorithm can effectively improve the BER performance of block-wise adaptive V-BLAST system, increase the block size and decrease feedback overhead.