延时反馈多天线信道的线性预编码方案

Linear precoding scheme for MIMO channels with delayed feedback

为了充分利用多天线系统发送端的延时信道参数,基于B ayes ian准则提出等误码准则和最小误比特率准则下的优化线性预编码方案。该方案考虑发送端的延时误差给系统带来的影响并对信道状态信息的条件期望进行奇异值分解。仿真结果表明:采用等误码准则下的优化方案使得系统在误比特率为10-4时获得约2.5 dB的信噪比增益,并且使各空间子信道的性能更接近,另外最小误比特率准则下的优化预编码方案也在稍增加系统复杂度的前提下有效地抑制延时信道对系统性能的影响并降低系统误比特率。

A powerful Bayesian linear precoding scheme which utilizes the delayed channel response was developed for equal error and minimum bit error rate criteria in multi-input-multi output communication systems. The transmitter design was based on the singular value decomposition of the conditional mean of the CSI. Simulation results show that the system achieves about 2.5 dB signal-to-noise ratio gains with a bit error rate of 10^-4 for equal error criterion and gives all the subchannels approximately equal transmission qualities. Furthermore, the scheme for the minimum bit error rate criterion also reduces the time delay effects and significantly reduces the average bit error rate with a marginal increase of complexity.