MIMO-OFDM广义空间信道频率响应间的相关性分析

Correlation Analysis Among Frequency Responses of MIMO-OFDM Wide-Sense Space Channels

多输入多输出-正交频分复用(MIMO-OFDM)技术被普遍认为是宽带无线通信的一种最具前景的技术。以往的研究重点放在如何利用收发天线间的多路空间信道,该文首次提出混合天线信道与波束信道的广义空间信道这一新概念。在不增加天线数目的前提下,广义空间信道能够增加空间信道的数量。当独立多径数远大于阵元数时,广义空间信道频率响应间的相关性较小,因此能够使空频码(SFC)的分集、编码及复用增益得到提高,从而提高MIMO-OFDM系统的性能。

The Multiple-Input Multiple-Output Orthogonal Frequency-Division Multiplexing （MIMO-OFDM） technique is widely accepted as the most prospective technique for broadband wireless communications. Previous studies have put emphasis on how to utilize space channels between receiving and emitting antennas. For the first time, a new conception of wide-sense space channels is proposed which combined antenna channels and beam channels. With no increasing the number of antennas, wide-sense space channels can increase the number of space channels. Under the condition of the multi-paths number was greater than the array elements number, the correlations among frequency responses of wide-sense space channels are very weak, hence, the diversity, coding and multiplexing gain of Space-Frequency Code （SFC） can be increased, so wide-sense space channels can improve the performance of MIMO-OFDM systems.