一种联合TOA与DPS估计的MIMO OFDM系统信道估计算法

An algorithm of channel estimation based on the joint estimation of TOA and DPS for MIMO OFDM systems

本文提出了一种基于联合TOA(到达时间)与DPS(时延功率谱)估计的MIMO OFDM系统信道估计算法,该算法借助导频设计,通过联合TOA与DPS估计对各路径时延位置进行精确定位,并在此基础上,对初始时域信道估计进行非线性滤波,从而改善了大时延扩展信道条件下由于导频子载波受限所导致的估计性能恶化现象。此外,文中还进一步分析、推导了该算法所适用的信道多径时延条件。最后,仿真结果也表明该算法可有效对抗大时延扩展信道,而且其MSE、BER性能要优于传统的时域最小二乘信道估计算法。

In this paper, an algorithm of channel estimation based on the joint estimation of TOA and DPS is proposed, which adopt the joint estimation of TOA and DPS for accurately positioning the multi-path delay by the pilot design. On the base of it, the initial channel estimation in time-domain can be nonlinearly filtered to improve the decreased performance of estimation for that the pilot subcarrier is limited under the channel condition of the large delay spread. Furthermore, the conditions of the multi-path delay adapting to the algorithm is also deeply analyzed and concluded. Finally, simulations also show that the algorithm can effectively resist the MIMO channel of large delay spread, and outperform the traditional TD-LS-CE in the performances of the MSE and BER.