关键词: 多载波, 垂直分层空时码, 预编码, 有限反馈, 码本扰动

Abstract: 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.

Key words: multi-carrier, vertical bell labs layered space time codes, precoding, limited feedback, codebook perturbation