基于图论的认知无线电频谱与功率联合分配算法研究

发布时间：2019-04-23 23:17

【摘要】：随着无线通信技术的快速发展,频谱资源的需求急剧增长。而目前频谱固定的分配策略严重制约了无线通信和服务应用的持续发展。认知无线电(Cognitive Radio, CR)技术能主动检测无线通信环境,动态地接入未被授权用户使用的空闲频段,实现频谱资源的共享,从而显著提高通信系统容量和频谱利用率。资源分配是认知无线电的关键技术,是实现认知无线电的重要环节。本文主要对认知无线电系统中基于图论模型的频谱与功率资源联合优化分配算法进行了研究,主要工作如下：(1)阐述了资源分配的研究背景和意义,总结了国内外研究现状,介绍了认知无线电资源分配技术以及图论的基本理论。(2)针对现有图论模型无法实现频谱与功率联合分配及频谱利用率较低问题,提出了基于改进图论模型的频谱与功率联合分配算法(简称为JSPA-IGTM算法),算法模型中充分考虑了次级用户之间的干扰情况,量化了次级用户之间的干扰,并用干扰阈值向量度量干扰程度,根据干扰程度分配频谱和相应的功率,利用粒子群优化方法实现了JSPA-IGTM算法资源联合分配的寻优过程。仿真实验结果表明,JSPA-IGTM算法与基于现有图论模型的资源分配算法相比,有效提高了频谱利用率。(3)针对粒子群优化(Particle Swarm Optimization, PSO)算法实现频谱与功率的联合优化分配容易陷入局部最优的问题,提出了实现频谱与功率优化分配的改进算法(简称为JSPA-IPH算法)。该算法结合了PSO算法与和声搜索(Harmony Search, HS)算法的优点,即JSPA-IPH算法不仅具备了HS算法良好的全局寻优能力,而且具备了PSO算法收敛速度快的特性。仿真实验结果表明,JSPA-IPH算法很好地适应于改进的联合资源分配图论模型,显著提高了系统吞吐量性能。
[Abstract]:With the rapid development of wireless communication technology, the demand for spectrum resources increases sharply. At present, the fixed spectrum allocation strategy seriously restricts the sustainable development of wireless communication and service applications. Cognitive radio (Cognitive Radio, CR) technology can actively detect the wireless communication environment, dynamically access the idle band used by unauthorized users, and realize the sharing of spectrum resources, thus significantly improving the capacity and spectrum efficiency of the communication system. Resource allocation is the key technology of cognitive radio and an important link to realize cognitive radio. This paper mainly studies the joint optimal allocation algorithm of spectrum and power resources based on graph theory model in cognitive radio system. The main work is as follows: (1) the research background and significance of resource allocation are described. This paper summarizes the research status at home and abroad, introduces the cognitive radio resource allocation technology and the basic theory of graph theory. (2) aiming at the problem that the existing graph theory model can not realize the joint allocation of spectrum and power and the low spectrum efficiency, A joint spectrum and power allocation algorithm (called JSPA-IGTM algorithm) based on improved graph theory is proposed. The interference between secondary users is fully considered and the interference between secondary users is quantized in the algorithm model. The interference threshold vector is used to measure the interference degree, and the spectrum and the corresponding power are allocated according to the interference degree. Particle swarm optimization (PSO) is used to realize the optimization process of the joint resource allocation of the JSPA-IGTM algorithm. The simulation results show that compared with the resource allocation algorithm based on the existing graph theory model, the JSPA-IGTM algorithm effectively improves the spectrum efficiency. (3) Particle Swarm Optimization (Particle Swarm Optimization,). PSO) algorithm is easy to fall into the local optimization problem to realize the joint optimal allocation of spectrum and power. An improved algorithm (JSPA-IPH algorithm for short) is proposed to realize the optimal allocation of spectrum and power. This algorithm combines the advantages of PSO algorithm and harmony search (Harmony Search, HS) algorithm, that is, JSPA-IPH algorithm not only has the good global optimization ability of HS algorithm, but also has the characteristics of fast convergence speed of PSO algorithm. The simulation results show that the JSPA-IPH algorithm is well suited to the improved joint resource allocation graph theory model, and the throughput performance of the system is significantly improved.
【学位授予单位】：东北大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN925

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