Convex-optimization-based precoding for MIMO downlinks  

作　　者：LI Xin-min BAI Bao-ming 

机构地区：[1]State Key Laboratory of Integrated Services Networks, Xidian University, Xi＇an 710071, China [2]Xi＇an University of Science and Technology, Xi＇an 710054, China

出　　处：《The Journal of China Universities of Posts and Telecommunications》2011年第6期22-26,共5页中国邮电高校学报（英文版）

基　　金：supported by the National Natural Science Foudation of China (60972046);the S&T Major Special Project (2009ZX03003-11-05, 2010ZX03003-003);the Scientific Research Program Funded by Shaanxi Provincial Education Commission (2010JK666)

摘　　要：In this paper, the design of linear leakage-based precoders is considered for multiple-input multiple-output （MIMO） downlinks. Our proposed scheme minimizes total transmit power under each user＇s signal-to-leakage-plus-noise ratio （SLNR） constraint. When the base station knows perfect channel state information （CSI）, suitable reformulation of design problem allows the successful application of semidefinite relaxation （SDR） techniques. When the base station knows imperfect CSI with limited estimation errors, the design problem can be solved using semidefinite program （SDP）. At the same time, it can dynamically allocate each user＇s SLNR threshold according to each user＇s channel state, so it is more feasible than other similar S1NR-based precoding methods. Simulation results show that using large SLNR thresholds, the proposed design has better bit error rate （BER） performance than maximal-SLNR precoding method at high signal-to-noise ratio （SNR）. Moreover, when the base station knows imperfect channel state information, the proposed precoder is robust to channel estimation errors, and has better BER preformance than other similar SINR-based precoding methods.In this paper, the design of linear leakage-based precoders is considered for multiple-input multiple-output （MIMO） downlinks. Our proposed scheme minimizes total transmit power under each user＇s signal-to-leakage-plus-noise ratio （SLNR） constraint. When the base station knows perfect channel state information （CSI）, suitable reformulation of design problem allows the successful application of semidefinite relaxation （SDR） techniques. When the base station knows imperfect CSI with limited estimation errors, the design problem can be solved using semidefinite program （SDP）. At the same time, it can dynamically allocate each user＇s SLNR threshold according to each user＇s channel state, so it is more feasible than other similar S1NR-based precoding methods. Simulation results show that using large SLNR thresholds, the proposed design has better bit error rate （BER） performance than maximal-SLNR precoding method at high signal-to-noise ratio （SNR）. Moreover, when the base station knows imperfect channel state information, the proposed precoder is robust to channel estimation errors, and has better BER preformance than other similar SINR-based precoding methods.

关 键 词：MIMO signal-to-leakage-plus-noise ratio （SLNR） linear precoding convex optimization 

分 类 号：TN929.5[电子电信—通信与信息系统] TP391[电子电信—信息与通信工程]