关键词: 多用户, 多输入多输出, 预编码, 有限反馈, 码本扰动

Abstract: Concerning the problem of performance loss due to limited feedback in multiuser MIMO downlink systems, a new limited feedback precoding for multiuser Multiple Input Multiple Output (MIMO) systems based on double codebook was proposed. The maximum SINR criteria was used for selecting optimal codeword from the Grassmannian codebook and perturbation codeword at the receiving, and feedback the Grassmannian precoding codeword index and perturbation codeword index to the transmitter, then the perturbation codeword was used at the transmitter to get optimal capacity, and compensating for the capacity performance loss due to the limited feedback. The simulation results show that the proposed method ensures Bit Error Rate (BER) performance and the cost of the feedback link, and the system throughput is improved effectively.

Key words: multiuser, Multiple Input Multiple Output (MIMO), precoding, limited feedback, codebook perturbation