针对多用户多输入多输出(MU-MIMO)下行链路,提出一种基于模式自适应的有限反馈机会传输策略.该策略引入门限机制,在每个时隙仅信道质量满足预设门限要求的移动台(MS)选择适当的传输模式,包括波束成形(BF)和空分复用(SM),并根据传输模式自适应反馈信道信息.基站(BS)根据获得的信道信息从候选用户中选择一个进行通信.最后对所提策略进行理论分析,并通过Monte-Carlo仿真证明,该策略能以少量的反馈开销获得高容量,同时保证低的中断概率.
A mode adaptive opportunistic transmission scheme in multiuser multi-input multi-output(MU-MIMO) downlink with limited feedback is introduced.In each time slot only eligible mobile station(MS) whose channel quality exceeds a preset threshold would select transmission mode,including beamforming(BF) and spatial multiplexing(SM) and adaptively feed channel information.With feedback information,base station(BS) schedules one user out of candidate MS.Analysis is employed in evaluating the proposed scheme.Monte-Carlo simulation shows that the scheme can achieve high capacity as well as low outage probability with limited feedback cost.