毕业设计英文翻译——认知无线电频谱感知算法仿真精编.doc

*仅供参考 上 海 电 力 学 院 毕业设计（英文翻译） 课题名称 认知无线电频谱感知算法仿真 院（系） 专 业 班 级 学 生 学 号 Implementation Issues in Spectrum Sensing for Cognitive Radios 认知无线电频谱感知的实现问题 Abstract:There are new system implementation challenges involved in the design of cognitive radios, which have both the ability to sense the spectral environment and the flexibility to adapt transmission parameters to maximize system capacity while co-existing with legacy wireless networks. The critical design problem is the need to process multi-gigahertz wide bandwidth and reliably detect presence of primary users. This places severe requirements on sensitivity, linearity, and dynamic range of the circuitry in the RF front-end. To improve radio sensitivity of the sensing function through processing gain we investigated three digital signal processing techniques: matched filtering, energy detection, and cyclostationary feature detection. Our analysis shows that cyclostationary feature detection has advantages due to its ability to differentiate modulated signals, interference and noise in low signal to noise ratios. In addition, to further improve the sensing reliability, the advantage of a MAC protocol that exploits cooperation among many cognitive users is investigated. 摘要：出现了一些新系统的实施挑战，其涉及认知无线电——具有感知频谱环境下的传输参数既适应能力和灵活性，以最大限度地提高系统容量，同时并存于传统无线网络。关键设计问题是需要处理多千兆赫宽的带宽，可靠地检测主用户的存在。这对灵敏度，线性度和在RF前端电路的动态范围有严格要求。为了通过处理增益而提高无线电灵敏度，我们调查了三种数字信号处理技术的感测功能：匹配滤波，能量检测和循环平稳特征检测。我们的分析表明：由于能够区分调制信号，干扰和噪声在低信噪比，循环平稳特征检测更有优势。此外，为了进一步提高检测的可靠性，MAC协议，它利用在许多认知用户合作的优势已经在这一块研究很久了。 I. INTRODUCTION 一、介绍 1. It is commonly believed that there is a spectrum scarcity at frequencies that can be economically use