V-BLAST OFDM最大发射分集度分析

Maximum transmit diversity gain analysis of V-BLAST OFDM

V-BLAST OFDM可以利用多径信道的频域选择性改善分集性能。目前相关研究缺乏分集度的理论分析,未能明确给出一种获取最大分集度的方法。针对这一问题,首先分析了V-BLAST系统可获得的最大分集度,然后找出了获得它所必须的条件,最后给出了一种可获得最大分集度的信号发射方法。在两发两收、BPSK调制、M.1225步行测试信道下的仿真结果表明:在误比特率为1e-3时,所提方法有2 dB的性能改善。

V-BLAST OFDM can use the frequency selectivity to improve diversity performance. However, related researches are lack of the performance analysis at the present day, and short of a method to obtain the maximum diversity gain. Focusing on this problem, this paper firstly analyzes the value of the maximum achievable diversity gain, and then finds the necessary condition to achieve it. Finally an effective transmit scheme is proposed to attain the gain. Simulation results in M.1225 pedestrian test channel show that the proposed algorithm has 2dB gain at BER of 1e-3 compared to conventional method using BPSK modulation.