毕业论文：认知无线电频谱分配技术及其应用分析.doc

认知无线电频谱分配技术 及其应用分析 摘要 近年来，随着无线通信技术的不断发展，频谱资源的使用日趋频繁，整个无线电频谱空间被划分的所剩无几。然而，从一些研究结果可以看到，频谱资源的缺乏更多是由于对不同无线接入技术的频谱分配不合理引起的。认知无线电技术在这样的背景下应运而生，它能够主动检测频谱使用情况，自适应的改变自身通信参数，择机的选择主用户暂不使用的频段进行通信，具有灵活、频谱利用率高等优点。 但是，对频谱的灵活应用要求认知无线电系统能够准确的检测并动态的分配频谱资源，其间还要为主用户的出现实现退避和切换功能，因此，频谱分配问题是认知无线电无线资源管理中的核心问题之一。目前，对认知无线电中的频谱分配问题研究已较为广泛，出现了基于图论理论等频谱分配问题模型，但是本领域的研究还刚刚开始。 本文首先对CR和频谱分配做简要介绍，主要阐述认知无线电的基本原理、功能，另外，着重介绍了认知无线电中频谱分配技术。然后，对频谱分配问题模型进行分析和比较，最后介绍CR在频谱分配的应用，并对结论和发展进行简单叙述。 关键词：认知无线电、频谱分配、图论理论 Cognitive radio spectrum allocation techniques And Its Application Abstract In recent years, with the continuous development of wireless communications technology, the increasingly frequent use of spectrum resources, the entire radio spectrum is divided into the little remaining space. However, the results can be seen from some of the spectrum is due to lack of resources more different wireless access technologies due to spectrum allocation is unreasonable. Cognitive radio technology emerged in this context, it can take the initiative to detect spectrum use, adaptive changes in their own communication parameters, choose the choice of the main users of the band temporarily used to communicate with a flexible, high spectral efficiency advantages . However, the flexible application of cognitive radio system need to detect accurately and allocation dynamic of spectrum resources, during this time it has to achieve the retreat and switching functions for the appearance of the main user, therefore, the problem of spectrum allocation is one of the core issues in the management of the cognitive radio radio resource. Currently, the reserch in the cognitive radio spectrum allocation problem is becoming wider, it has emerged based on graph theory problem of spectrum allocation model, However, the field research has just begun. This article has a brief description of CR and spectrum allocation at first, mainly elaborated the basic principles of cognitive radio functions, also highlights the spectrum