MIMO系统V-BLAST自适应迭代极大似然检测研究

为了提高系统传输性能,有效利用信道资源,提高频谱利用率.在时变衰落信道下采用了分层垂直空时结构,同时文中提出了一种自适应极大似然估计检测方法,系统根据各平均误码率及反馈信噪比自适应地选择调制类型,按列检出数据,该方法收敛时间快,高阶调制牺牲增益低的信道换取整体频谱效率提高.试验结果表明自适应垂直BLAST迭代检测每0.1%误码率可以比传统检测算法提高4.1dB.自适应极大似然估计检测的分层垂直空时结构其频谱效率优于单纯的垂直BLAST检测.

Adaptive iterative likelihood detection algorithm for V-BLAST MIMO system

A novel iterative likelihood detection algorithm of adaptive modulation for V-BLAST MIMO communication system over time-varying fading channel is proposed to utilize channel resource sufficiently.The system selects adaptive modulation according to the average bit error rate and improves the spectrum ratio.Based on the Vertical Layered Space-Time(BLAST) structure,an adaptive iterative detection data stream algorithm using the maximum likelihood estimate was obtained.Firstly,the adaptive modulation mode was decided by a set of thresholds of receiver average BER defining constellation size;secondly,the data stream was detected by the adaptive iterative likelihood detection equation.The theoretic analysis and simulation results show that the novel adaptive V-BLAST likelihood detection algorithm is robust and easy to implement.The BER of per 0.1% of the proposed algorithm can obtain 4.1 dB gain performance more than that of the traditional algorithm.The spectral efficiency of the algorithm is superior to that of the pure V-BLAST method.