宽带无线多媒体集群的信道信息获取及反馈策略研究

发布时间：2018-10-10 16:43

【摘要】：宽带集群通信系统(Boardband Trunking Communication,B-TrunC)在近年来得到了极大发展和广泛应用,基于时分双工的长期演进计划(Time Division Duplex Long Term Evolution,TD-LTE)的B-TrunC物理层是它的一个重要的发展方向。本文研究了基于TD-LTE的B-TrunC系统的信道信息获取、系统反馈策略及其在宽带无线多媒体实验样机上的实现。论文研究了B-TrunC系统基于TD-LTE标准的物理层协议,梳理了下行数据共享信道和上行数据共享信道的总体流程;设计了B-TrunC系统的链路自适应总体流程;搭建了基于TD-LTE的B-TrunC系统在Matlab仿真平台下的基础链路,分析了业务信道在加性高斯白噪声下的性能。论文以莱斯信道为典型信道研究了B-TrunC系统的信道估计技术。论文首先以矩估计法、K-S估计法和最大似然估计法研究了莱斯因子的估计技术,前两种方法只利用了信号的包络,最大似然法由于同时利用了包络和相位进行估计能取得更优的性能,但复杂度较高,而矩估计法能在性能和复杂度之间取得较好的折衷;论文研究了莱斯信道下的最小二乘估计算法和线性最小均方误差估计算法,并提出一种加权并偏移修正的优化算法,理论分析和仿真表明优化算法能增强噪声抑制,且在莱斯因子越大时,噪声抑制能力越强,估计越精确。论文研究了B-TrunC系统的信干噪比估计技术,分析了基于循环前缀相关性、基于空子载波和基于导频干扰抵消的估计算法,利用上述算法估计噪声方差后,论文考虑了存在天线间干扰时基于均衡后数据的信干噪比测量算法,接着分析了衡量总链路性能的信干噪比有效映射算法。论文通过理论分析和数字仿真对比了典型信干噪比估计算法,基于MATLAB搭建了算法仿真链路,完成适于样机实现的信干噪比算法选型。论文研究了B-TrunC系统的链路自适应技术,主要集中在下行链路信道参数反馈算法的研究,分析了信干噪比到信道质量指示的映射方法,分别研究了基于信道相关矩阵和容量的秩指示算法,基于信道矩阵分解和互信息的预编码矩阵指示算法,对其进行了理论分析和数字仿真,结果表明链路自适应技术能保证可靠性的同时增加系统吞吐量最后研究了链路自适应技术在实验样机上的实现。论文最后总结了全文的研究结果,并指出了下一步的研究方向。
[Abstract]:Wideband trunked communication system (Boardband Trunking Communication,B-TrunC) has been developed and widely used in recent years. The B-TrunC physical layer based on time-division duplex long-term evolution plan (Time Division Duplex Long Term Evolution,TD-LTE) is one of its important development directions. In this paper, the channel information acquisition, system feedback strategy and its implementation in wideband wireless multimedia experiment prototype of B-TrunC system based on TD-LTE are studied. This paper studies the physical layer protocol of B-TrunC system based on TD-LTE standard, combs the overall flow of downlink data sharing channel and uplink data sharing channel, and designs the link adaptive overall flow of B-TrunC system. The basic link of B-TrunC system based on TD-LTE under Matlab simulation platform is built, and the performance of traffic channel under additive Gao Si white noise is analyzed. In this paper, we study the channel estimation technology of B-TrunC system using Rice channel as a typical channel. In this paper, the moment estimation method, K-S estimation method and maximum likelihood estimation method are used to study the estimation technique of Rice factor. The first two methods only use the envelope of the signal. The maximum likelihood method can obtain better performance because of the use of both envelope and phase estimation, but the complexity is higher, while the moment estimation method can achieve a better tradeoff between performance and complexity. In this paper, the least square estimation algorithm and the linear least mean square error estimation algorithm in Rice channel are studied, and a weighted and offset correction optimization algorithm is proposed. Theoretical analysis and simulation show that the optimization algorithm can enhance noise suppression. The higher the Rice factor is, the stronger the noise suppression ability is and the more accurate the estimation is. In this paper, the signal-to-noise ratio estimation technology of B-TrunC system is studied, and the estimation algorithm based on cyclic prefix correlation, empty subcarrier and pilot interference cancellation is analyzed. In this paper, the signal-to-noise ratio measurement algorithm based on equalized data is considered in the presence of inter-antenna interference, and then the effective SINR mapping algorithm to measure the performance of the total link is analyzed. Through theoretical analysis and digital simulation, the typical signal-to-noise ratio estimation algorithm is compared, and the algorithm simulation link based on MATLAB is built to complete the selection of signal-to-noise ratio algorithm suitable for the prototype. In this paper, the link adaptive technology of B-TrunC system is studied, which mainly focuses on the downlink channel parameter feedback algorithm, and analyzes the mapping method from signal-to-noise ratio to channel quality indication. The rank indication algorithm based on channel correlation matrix and capacity, the precoding matrix indication algorithm based on channel matrix decomposition and mutual information are studied, and the theoretical analysis and digital simulation are carried out. The results show that the link adaptive technology can guarantee the reliability while increasing the throughput of the system. Finally, the realization of the link adaptive technology on the experimental prototype is studied. Finally, the paper summarizes the research results and points out the next research direction.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN929.52

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