自适应OFDM系统中基于压缩感知的反馈压缩新方法

Compressed Sensing Based Feedback Compression in Adaptive OFDM Systems

在多用户无线通信系统中,采用自适应调制与调度技术能够有效提高系统吞吐量。为此,必须反馈信道质量指示(Channel Quality Indication,CQI)。在多载波自适应正交频分复用(Orthogonal Frequency Division Multiple-xing,OFDM)系统中CQI反馈速率非常高,令系统难以承受。因此,必须对反馈信息加以压缩。近年来提出了一种新理论,称为压缩感知(Compressed Sensing,CS)。基于CS理论提出了一种新的CQI反馈方案。通常,基于离散余弦变换的压缩方案被认为是最佳压缩方案,仿真结果表明所提出的新方法性能优于基于离散余弦变换的压缩方案。

In muhiuser wireless communication systems, adaptive modulation and scheduling are promising techniques for increasing the system throughput. To achieve this goal, it is necessary to feedback the information of channel quality indication （CQI）. The required feedback rate can be prohibitively high in adaptive orthogonal frequency division multiplexing （OFDM） systems, so the feedback information needs to be compressed. In this paper, a novel CQI feedback scheme is proposed based on the recently pro- posed theory of compressed sensing, and its performance is shown to outperform the compression method based on the discrete cosine transform which is usually considered as the best.