MIMO-OFDM系统下基于频谱利用率的自适应发射方案选择  

Spectrum Efficiency Based Adaptive Transmission Approach in MIMO-OFDM System

作　　者：廖韫婧[1] 何迪[1] 

机构地区：[1]上海交通大学电子工程系,上海200240

出　　处：《无线通信技术》2009年第2期20-25,共6页Wireless Communication Technology

基　　金：国家自然科学基金项目(No.60772100);上海市重大科技攻关项目(No.06DZ15013)。

摘　　要：本文提出并分析了一种MIMO-OFDM系统下,考虑相关空间信道的自适应发射方案选择算法。采用比特交织卷积编码,在以下三种发射模式间进行选择:空间复用、空间分集和复用/分集的混合模式。我们通过对MIMO-OFDM系统中采用迫零(ZF)接收机在高信噪比条件下的错误概率的简化分析,得出空间相关的多天线系统下的自适应选择算法,在给定的误码率条件下可获得使频谱利用率最大化的编码速率、调制模式和发射模式,并反馈到发射端,有效改善了系统的性能。In this paper we propose an adaptive transmission approach for spacially correlated MIMO - OFDM system. It considers switching among three transmission modes with bit - interleaved convolutional coder： space multiplexing, space diversity and the combination mode of multiplexing and diversity. By simplifying the BER expression under high SNR in MIMO - OFDM system with ZF receiver, we derive an adaptive transmission algorithm in a spaciaUy correlated MIMO system. Given a BER limit, the approach can select a combination of code - rate, modulation mode and transmission mode that can maximize the system spectrum efficiency, and feed back the results to the transmission end. From simulation results it can be found that the scheme improves the system performance effectively.

关 键 词：MIMO—OFDM 迫零检测 空时编码 频谱利用率 

分 类 号：TN911[电子电信—通信与信息系统]