多天线OFDM系统的线性优化

从Jakes信道模型出发,用KKT优化方法,从信道部分特性已知的情况推导了多天线OFDM系统中发射机与接收机的线性最优化设计问题。仿真比较了多天线OFDM系统的各个子载波之间采用合作的线性优化与非合作的线性优化两种方法在不同最大多普勒频移和反馈时延下发送符号的均方误差。仿真结果表明,当信道特性部分已知时,子载波之间合作的线性优化较之非合作的线性优化有更小的均方误差。可为存在反馈时延的多天线OFDM系统设计提供指导

Linear optimization in multiple antenna OFDM system

When the channel state information or the partial channel state information is known, the linear joint transmitter and receiver optimization has a better performance than the space-time coding and spatial multiplexing methods. Based on Jakes model and KKT optimization method, the linear joint transmitter and receiver optimization is derived when partial channel state information is known. The mean square error(MSE) using the cooperated linear optimization between sub-carriers and the independent linear optimization between sub-carriers with different feedback time delays and different maximal Doppler frequent shifts in OFDM systems are compared through digital simulation. The result indicates that the cooperated method outperforms the independent one in MSE, which can provide a reference for the design of multiple antenna OFDM systems with feedback time delay.