认知无线电网络中协作中继技术的研究

发布时间：2018-03-16 04:01

本文选题：认知无线电　切入点：协作传输　出处：《山西大学》2014年硕士论文　论文类型：学位论文

【摘要】：移动终端尤其是智能终端和无线应用的广泛使用,使无线通信技术和移动通信产业得到飞速发展,但同时也给我们带来了很多挑战。比如作为移动通信中不可再生的稀缺资源,无线频谱的需求也呈指数型增长。因此如何有效地使用频谱来提高提高频谱利用率是目前重要的问题。认知无线电(Cognitive Radio, CR)技术和协作中继传输(Cooperative Relay Transmission, CRT)技术作为能够解决上述问题的新型技术受到广泛的关注。认知无线电技术是一种允许认知用户感知周围环境,通过检测找到周围的空闲授权频谱并智能地利用这些频谱来传输数据的技术。协作传输技术是指用户通过中继的协作增大传输距离,提高分集增益,有效地抵抗信道衰落。将协作传输技术应用于认知网络中不仅能够提高系统的频谱利用率,而且还使用户在中继节点的协助下提高了传输速率。因此,本论文以基于协作中继的认知网络为研究对象,研究了以下内容：首先,本文研究了一种次用户通过帮助主用户传输数据获得频谱接入机会的协作模型。研究结果表明,这种协作模型将频谱分成两部分来分别传输主用户和次用户的数据,既可以避免用户之间的相互影响,又可以提高资源的使用率,而且还提高了增加了次用户的传输速率。本论文第三章详细叙述了这种模型中数据传输过程和数值仿真结果。此外,本论文还研究了一种主用户与多个次用户共存的协作模型,并且基于此模型提出了协作功率和频谱资源分配算法,并在改变主用户传输距离情况下对次用户的传输速率和主用户的中断概率进行了数值仿真。研究结果表明,这种协作模型可以在不增加发射功率的条件下提高系统性能。本论文第四章详细叙述了这种模型中数据传输过程和数值仿真结果。
[Abstract]:With the wide use of mobile terminals, especially intelligent terminals and wireless applications, the wireless communication technology and the mobile communication industry have developed rapidly, but at the same time, it has brought us many challenges, such as being a scarce and non-renewable resource in mobile communications. The demand for wireless spectrum is also increasing exponentially. Therefore, how to use spectrum effectively to improve spectrum efficiency is an important issue. Cognitive Radio Cognitive Radiotechnology and Cooperative Relay Transmission (CRT) Technology. New technologies that can solve these problems have received widespread attention. Cognitive radio is a technology that allows cognitive users to perceive the surrounding environment. Technology that detects the free spectrum around it and uses it intelligently to transmit data. Cooperative transmission means that users increase transmission distance and diversity gain through relay cooperation. The application of cooperative transmission technology in cognitive networks can not only improve the spectral efficiency of the system, but also increase the transmission rate with the assistance of relay nodes. In this thesis, the cognitive network based on cooperative relay is taken as the research object, and the following contents are studied: firstly, this paper studies a cooperative model for secondary users to obtain spectrum access opportunities by helping primary users to transmit data. The results show that:. This collaboration model divides the spectrum into two parts to transmit the data of the primary and secondary users, which can avoid the interaction between users and increase the utilization of resources. In chapter 3, the data transmission process and numerical simulation results of this model are described in detail. In addition, this paper also studies a cooperative model in which primary users and multiple secondary users coexist. Based on this model, a cooperative power and spectrum resource allocation algorithm is proposed, and the secondary user's transmission rate and the primary user's interrupt probability are numerically simulated under the condition of changing the transmission distance of the primary user. This cooperative model can improve the system performance without increasing the transmission power. The data transmission process and numerical simulation results of this model are described in detail in Chapter 4th of this paper.
【学位授予单位】：山西大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN925

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