提出一种基于叠加训练序列的MIMO信道估计模型,该模型信道估计方法不占用额外的信号带宽并具有较高的估计精度。通过最小二乘(LS)方法,推导出模型信道估计误差的均方差、信道容量的下限以及更加紧凑的Cramer-Rao界。数值模拟结果表明,相同条件下,采用叠加的训练序列要比直接采用训练序列对系统容量的改善5 dB左右。此外,模型所采用的算法结构简单,计算量小,有很大的实际应用前景。
An MIMO channel estimation model using superimposed training sequences is proposed, which doesn't take any extra signal spectral and has high accuracy. Through exploiting the least square method, a closed-form solution for the estimation of variance and the lower bound of channel capacity, as well as a rather compact Cramer-Rao bound are derived. Simulation results show that the system has higher performance by using superimposed training sequences than that using training sequences, which is improved about 5 dB. Moreover, the algorithm has a simple structure and low computation complexity, which is very promising in the reality wireless communication.