认知无线电中频谱感知技术

固定频谱分配政策导致频谱使用率低下,为克服这一缺点,人们提出使用认知无线电技术实现动态频谱接入,从而有效利用频谱空穴。频谱感知是认知无线电的关键技术。文中介绍了目前已提出的频谱感知技术:发射机检测(包括匹配滤波器检测、能量检测和周期平稳特征检测)、合作检测、接收机检测及基于干扰温度的检测,仿真分析了各种方法的优缺点及有待解决的问题。为满足多用户环境和实时性要求,仍需探讨新的频谱感知方法,提高检测性能。

Spectrum Sensing Technologies for Cognitive Radios

Today's wireless networks are governed by a fixed spectrum assignment policy which results in low efficiency in spectrum utilization.Cognitive radio has been proposed to use dynamic spectrum access so as to use spectrum holes efficiently.In this paper,several spectrum sensing technologies are introduced in detail which includes transmitter detection,cooperation detec- tion,receiver detection and interference temperature-based detection.The main advantages and shortcomings of each method are also analyzed.However,novel spectrum sensing methods still need to be searched to solve the multi-user problem and reduce the detection time.