协作多点多用户时偏补偿算法研究与性能分析

发布时间：2018-05-20 20:06

本文选题：协作多点 + 符号定时偏差　；参考：《西安电子科技大学》2014年硕士论文

【摘要】：随着IMT-Advanced技术的演进,新一代宽带无线通信领域中出现了一系列的新技术。协作多点通信技术是一个颇具前瞻性的概念,旨在提高小区边缘用户的通信质量。在协作多点多用户通信系统中,通过基站间协作降低干扰对系统性能的影响,带来增益。但是面临的问题是协作多点技术给系统带来的增益是在系统完全同步的理想情况下产生的,而在实际系统中,由于用户的移动性,协作多点多用户通信系统的符号定时同步会出现偏差,带来码间干扰,严重影响系统服务质量。本文针对该问题,对协作多点多用户通信系统的时偏补偿算法进行了研究,并对其性能作了详细的分析,所取得的主要研究成果为:1.对协作多点多用户通信系统的符号定时偏差的补偿算法进行了研究。提出了一种基站实现预补偿,用户实现后补偿的增强型联合补偿算法。在证明协作多点多用户的时偏不能完全消除的情况下,增加了剩余时偏量在可容忍的时偏范围内的约束,建立带约束优化方程,完成了增强型的符号定时偏差补偿算法的建模。2.根据建立的带约束优化方程,对求解算法进行了研究。研究了两种算法,一个是广义逆矩阵显示封闭求解,一个是带约束的矩阵QR分解循环迭代的开放式求解。重点研究了LSQR分解法,对基本的求解方法做了改进,引入约束条件,采用循环迭代的方式进行计算,最终计算得到各个预补偿值和后补偿值。3.利用计算机,以LTE-A下行链路为例进行了仿真,对增强型时偏补偿算法的性能进行了验证。仿真结果表明两种优化求解算法均能实现时偏补偿方法,降低了系统的误码率。对两种优化求解算法的消耗时间与补偿性能进行了对比。4.针对协作多点多用户的信号开销对系统的性能影响进行了分析。针对时偏补偿算法的开销信息和剩余时偏量对系统用户吞吐量的影响分别进行了研究,并用计算机仿真。结果表明选择适当协作基站数和进行时偏补偿的重要性。
[Abstract]:With the evolution of IMT-Advanced technology, a series of new technologies have emerged in the new generation broadband wireless communication field. Cooperative multipoint communication technology is a forward-looking concept aimed at improving the communication quality of cell edge users. In the cooperative multipoint multiuser communication system, the interference is reduced by the cooperation between the base stations, which brings the gain. However, the problem is that the gain brought by the cooperative multi-point technology is generated under the ideal condition of complete synchronization of the system, and in the real system, because of the mobility of the user, Symbol timing synchronization in cooperative multiuser communication systems will cause inter-symbol interference (ISI), which will seriously affect the quality of service (QoS) of the system. In this paper, the time offset compensation algorithm for cooperative multipoint multiuser communication system is studied, and its performance is analyzed in detail. The main research result is: 1. The compensation algorithm of symbol timing deviation in cooperative multi-user communication system is studied. In this paper, an enhanced joint compensation algorithm for base station and user is proposed. When it is proved that the time offset of the cooperative multi-point and multi-user can not be completely eliminated, the constraint of the residual time offset in the tolerance range of time offset is added, the optimization equation with constraints is established, and the modeling of the enhanced symbol timing offset compensation algorithm is completed. 2. According to the constrained optimization equation, the algorithm is studied. Two algorithms are studied, one is the generalized inverse matrix display closed solution, the other is the open iterative solution of the constrained matrix QR decomposition cycle iteration. The LSQR decomposition method is studied emphatically, and the basic solution method is improved. The constraint condition is introduced, and the cyclic iteration method is used to calculate. Finally, each pre-compensation value and post-compensation value .3are calculated. The performance of the enhanced time-offset compensation algorithm is verified by computer simulation with LTE-A downlink as an example. The simulation results show that both algorithms can achieve time-offset compensation and reduce the bit error rate (BER) of the system. The cost time and compensation performance of the two optimization algorithms are compared. 4. 4. The effect of signal overhead on the performance of the system is analyzed. The effects of the overhead information of the time-offset compensation algorithm and the residual time-offset on the throughput of the system are studied and simulated by computer. The results show that it is important to select the appropriate number of cooperative base stations and compensate the time bias.
【学位授予单位】：西安电子科技大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN929.5

【相似文献】