MIMO-OFDM系统中一种有效的信道估计方法

Efficient channel estimation method for MIMO-OFDM systems

为降低信道估计算法的复杂度,给出了MIMO OFDM(MultipleInputandMultiplwOutput OrthogonalFreuencyDivisionMultiplexing)系统中的一种信道估计实现方案,采用STBC(Space TimeBlockCode)训练序列,LMS(LeastMeanSquare)迭代算法估计信道响应,避免了矩阵的求逆运算,与基于MMSE(MinimumMeanSquoreEr ror)和LS(LeastSquare)的MIMO信道估计算法相比,具有运算复杂度低、跟踪能力强的优点,计算机仿真结果也显示了它的有效性和优越性。

The growing demand for high-speed multimedia services has created the need for improving the data transmission rates and the spectral efficiency of the wireless communications, and the MIMO-OFDM(Multiple Input and Multiplw Output-Orthogonal Freuency Division Multiplexing) technique is one of the effective measures to solve the problem. In a MIMO-OFDM system, an accurate channel estimator is key to ensure the performance of the system. A simple channel estimation method for a MIMO-OFDM system is presented, which uses LMS(Least Mean Square) iterative algorithm using the STBC(Space Time Block Coded) training blocks. Compared with the channel estimator algorithms based on MMSE(Minimum Mean Squore Error) and LS(Least Square) althorithms, it offers a lower complexities and a better ability to track the channels. Finally the validity and advantages of the method proposed are demonstrated in the numerical results.