TD-LTE非理想信道互易性下的下行单用户波束成形算法

Downlink SU-MIMO Beamforming Strategy for Non-ideal Channel Reciprocity in TD-LTE

在TD-LTE系统中由于上下行信道的时变特性、干扰非对称特性以及射频器件非对称特性会影响基于信道互易性的波束成形技术应用,降低系统增益。针对非理想信道互易性下的预编码矩阵设计问题,以最大化接收信号平均信干噪比做为目标函数,通过计算信道状态信息(CSI)估计值以及互易性误差的统计自相关矩阵,构造正则矩阵束,将最大化接收信干噪比的预编码矩阵求解问题转化为正则矩阵束的广义特征向量求解问题。计算机仿真验证了算法设计的预编码矩阵能有效增强系统的鲁棒特性。

The channel information time-varying character,asymmetric cell interference and the RF paths in antennas and the baseband module between uplink and the downlink will worsen the application of reci-procity and reduce the beamforming gain in TD-LTE system. Aiming at designing pre-coding for non-ideal reciprocity,a cost function with maximizing the Signal-to-Interference plus Noise Ratio（SINR） in statisti-cal average way is proposed. The regularization matrix pencil is deduced with the statistical correlation ma-trix of the prior channel state information（CSI） matrix and the reciprocity mismatch error matrix. The pre-coding matrix designing can be translated to the deriving generalized eigenmatrix. The simulation shows that the algorithm can build a robust system.