码本扰动有限反馈多载波分层空时检测方法

Detection for multi-carrier layered space-time systems with limited feedback based on codebook perturbation

针对有限反馈多载波分层空时方案存在反馈链路开销量减少引起性能缺失的问题,利用矩阵线性变换特性,提出了一种基于码本扰动的有限反馈多载波分层空时预编码检测方法。该方法利用多载波各子载波信道频域之间的相关性,在接收端仅需估计部分子载波信道信息,采用相应的准则从预置码本中选取主码字及扰动码字,用扰动码字对主码字进行线性变换扰动以达到容量最优,在发送端根据反馈的码本矩阵的索引重构各子载波预编码矩阵,最后在接收端采用非线性循环迭代检测方法,以补偿由于有限反馈导致的性能缺失。仿真结果表明,提出的方法在保证反馈链路开销的情况下,一定程度上提高了系统吞吐量,改善了系统误码性能。

Considering the problem of feedback cost and performance loss for multi-carrier layered space-time systems with limited feedback, with linear transformation matrix, an improved nonlinear detection method for multi-carrier layered space-time systems with limited feedback based on codebook perturbation is proposed. This method uses the channel frequency-domain correlations, and only a part channel of subcarrier should be estimated at the receiver. The corresponding standards is used for selecting optimal codewords and disturbance codewords from the Grassmannian codebook at the receiving according to the channel state information. Then the disturbance codewords is used to the optimal codewords for linear transform disturbance in order to achieve the optimal capacity. According to the feedback of the index of the matrix code, gets all sub-carrier reconstruction at the transmitter. Finally using nonlinear iteration detection to compensate for the performance loss due to the limited feedback. Simulation results show that the proposed method ensures system throughput, reduce the cost of the feedback link and BER performance at some extent.