MIMO-OFDM系统中一种新的信道估计方法

提出了多输入多输出-正交频分复用(MIMO-OFDM)系统中一种新的信道估计方法.根据最小均方误差的准则,推导出了求解信道频率响应的方程,方程求解的运算量主要集中在一个矩阵的求逆上.对每一个符号,此矩阵是固定的,所以矩阵的求逆仅需计算一次,整个求解过程的运算量较低.计算机仿真给出了这种方法的归一化均方误差和误码率性能.仿真结果表明,本文方法在多普勒频移为60Hz和360Hz下,其归一化的均方误差值相当,表明本文方法可以在不同的移动环境中良好工作.在不同的数据调制方式和不同的多普勒频移下,本文方法的误码率性能优于最小平方算法,略差于线性最小均方误差算法,但复杂度大大降低.

A novel channel estimation method for MIMO-OFDM systems

A novel channel estimation method for multiple input multiple output-orthogonal frequency division multiplexing (MIMO-OFDM) systems was proposed. Based on the criterion of minimum mean square error, an equation of resolving the channel frequency response was then obtained. The computing complexity mainly lay in the solution of inversion of a matrix. For each OFDM symbol, the matrix was constant. So the operation of inversion of the matrix was needed only once and the computing complexity was not high. Computer simulation shows the NMSE(normalized mean square error) and the BER(bit error ratio) performance. The simulation results show that the new channel estimation method has the similar NMSE performance with Doppler shifts of 60Hz and 360Hz. And this means that the proposed novel channel estimation method may work well at different mobile environments. With data modulation of QPSK and 16QAM, and Doppler shifts of 60Hz and 360Hz, the BER performance of the proposed method was better than that of LS method and little worse than that of LMMSE method. However, compared to LMMSE method, the computing complexity of the proposed method decreased dramatically.