节点文献
多发送天线系统下检测算法的研究
Detection Algorithms in the Multi-transmit Antenna System
【作者】 陈超;
【导师】 王东昱;
【作者基本信息】 北方工业大学 , 信号与信息处理, 2012, 硕士
【摘要】 多输入多输出(MIMO)技术是未来无线通信的发展方向,它改变了以往的单天线收发结构,在发射端和接收端同时使用多天线,不仅能够大幅度提高信道容量,而且能够提供复用增益和分集增益,同时提高信息传输速率和改善信号接收质量。垂直分层空时码(V-BLAST)是MIMO系统中一种典型的分层空时码,可以获得很高的频带利用率和较低的系统复杂度,是实现MIMO系统的优秀解决方案之一。MIMO系统接收端检测算法的设计对系统的误码率性能和复杂度有着较大的影响,研究高性能、低复杂度的MIMO信号检测算法具有重大意义。本文在国内外相关研究工作的基础上对MIMO系统信号检测技术进行了研究。首先分析了MIMO系统V-BLAST结构的模型,其次介绍了基本的检测算法,包括最大似然检测算法(ML)、迫零检测(ZF)、最小均方误差检测(MMSE).连续干扰抵消检测(SIC)、排序连续干扰抵消检测(OSIC)以及正交三角(QR)分解检测等,并通过理论分析和性能仿真对检测算法的性能和复杂度进行了比较。本文随后重点研究了球形检测(SD),在阐述球形检测基本原理的基础上,对多种球形检测算法初始半径选择方法以及搜索半径更新策略进行了理论分析和性能比较,并讨论了K-BEST检测和我们提出的改进搜索策略的K-BEST检测。理论分析和仿真结果均表明,改进的K-BEST检测在几乎不损失性能的同时大幅降低了复杂度。
【Abstract】 As one of the development direction of future wireless communications, multi-input multi-output technology has changed the previous single antenna system structure and uses multiple antennas at the transmitter and receiver both, which not only can increase the channel capacity significantly, but also can provide reuse gain and diversity gain, increase the information transmission rate and improve the signal reception quality. V-BLAST is a typical layered space-time code in MIMO system and an excellent solution for MIMO system, which can get higher bandwidth efficiency and lower system complexity. Design of the MIMO system receiver detection algorithm has a greater impact on the system BER performance and complexity, which makes great significance on the research of MIMO system detection algorithm with high performance and low complexity.In this paper, we do some research work on MIMO system detection algorithm on the basis of relevant research work at home and abroad. First, we have an analysis on the structure model of the MIMO system, then we have an introduction of the basic detection algorithm, including maximum likelihood detection, zero forcing detection, minimum mean square error detection, successive interference cancellation detection, ordered successive interference cancellation detection and orthogonal decomposition of triangular detection and so on, finally we compare their performance and complexity through theoretical analysis and performance simulation.The paper will then focus on sphere detection. On the basis of describing the basic principle of the sphere detection, we do theoretical analysis and performance simulation on a variety of initial radius selection methods and search radius update strategy of sphere detection algorithm, and discuss the K-BEST detection algorithm and our proposed improved search strategy K-BEST algorithm. Both the theoretical analysis and simulation results shows that the improved K-BEST algorithm reduces the complexity dramatically while with almost no loss of the performance.