基于迫零检测的异步V-BLAST最优发射功率分配  

Optimal Transmit Power Allocation for Asynchronous V-BLAST System Using Zero-Forcing Detecting

作　　者：官鹭[1] 唐友喜[1] 邵士海[1] 邓凯[1] 

机构地区：[1]电子科技大学通信抗干扰技术国防科技重点实验室,成都610054

出　　处：《电子与信息学报》2010年第4期786-789,共4页Journal of Electronics & Information Technology

基　　金：国家自然科学基金(60902027;60832007;60901018)资助课题

摘　　要：由于异步发射V-BLAST各路子流的符号在时间上未对齐,同步V-BLAST所采用的逐符号功率分配方法不再适用。针对这个问题,该文提出了一种以块平均误比特率为优化目标,逐符号块进行功率分配的方法。该方法首先计算每个符号的瞬时信噪比,然后求出异步符号块的平均误比特率,最后求解优化问题得到各天线的最优发射功率值。平坦瑞利衰落信道下的仿真表明:两发两收、BPSK调制、迫零检测的异步V-BLAST,误比特率为10?3时最优功率分配有2dB的性能改善。Since different delay offsets are applied to the spatially multiplexed data streams of asynchronous vertical Bell Labs layered space-time （V-BLAST）,the symbol-by-symbol power allocation method used in synchronous systems is invalid. According to this issue,a block-by-block power allocation algorithm is proposed to minimize the Block Average Bit Error Rate （BABER）. This algorithm firstly computes the instantaneous SNR per symbol. Then BABER of asynchronous block is worked out. Finally,the optimum transmit power of each antennas is obtained from the solution of an optimization problem. Simulation results in flat Rayleigh fading channel show that the proposed algorithm has 2 dB gain at BER of 10？ 3compared to the 2Tx2Rx asynchronous V-BLAST using BPSK modulation and zero-forcing detection.

关 键 词：无线通信 V-BLAST 异步 迫零检测 发射功率分配 块平均误比特率 

分 类 号：TN92[电子电信—通信与信息系统]