基于有限反馈的数据流数自适应SDMA

Limited Feedback SDMA with Adaptive Multiplexing Order

针对目前绝大部分有限反馈自适应SDMA由于使用固定满波束发送策略而导致在稀疏网络中严重的用户间干扰的问题,该文提出了一种基于有限反馈的数据流数自适应SDMA,该方案能通过自适应地选择并行发送波束的数目来达到有效控制用户间干扰的目的。具体实现如下:通过用户的有限反馈信息,以及信道的二阶统计信息,基站端使用约束最大似然估计的方法估计出使用不同数目发送波束的发送模式所支持的最大和吞吐量,从而自适应地选择最优的发送模式。仿真结果表明:该文提出的方案能在增加很少反馈量的前提下显著改善现有SDMA方案的性能。

In order to tackle the inter-user interference issue of the limited feedback SDMA which uses a fixed number of active beams to simultaneously transmit signal, this paper proposes a novel limited feedback SDMA capable of adaptively selecting the optimal number of simultaneous beams, i.e., the optimal multiplexing order. In particular, the base station uses the feedback information from users and the spatial correlation matrix at the transmitter to ML estimate the maximum supported sum throughput for different number of active beams, thus the multiplexing order with the optimal performance can be chosen in each implementation of SDMA. Simulation results demonstrate that the proposed SDMA considerably outperforms the conventional SDMA in terms of throughput, with a small additional feedback overhead.