随着无线电授权频段的日益紧缺和ISM公用频段的日益拥挤，无线传感器网络的研究和应用不可避免地要解决获取频谱资源的难题。而且，无线传感器网络的低成本特性使得花费大量资金注册申请频谱使用权的做法并不合理。因此，本文探讨了基于认知无线电技术为传感器网络寻找新的可用频谱资源，提出了衰落信道下两种基于能量检测的协作频谱检测方法。仿真结果表明，所提出的检测方法具有可靠的频谱检测概率，为寻找可用频谱资源奠定了基础。

With the increasing lack of allocable spectrum and crowding of ISM (Industrial, Scientific and Medical) bands, the research and application of wireless sensor networks (WSN) will face a major difficulty that acquire usable spectrum. Moreover，purchasing spectrum rights with lots of money is unreasonable under an emphasis on low cost to WSN. Thus an alternate method based on the concept of Cognitive Radio is explored to capturing spectrum for WSN. Two cooperative detection techniques based on energy detection are introduced, with the consideration of channel shadowing or fading. The simulation results show that the proposed energybased cooperative spectrum sensing methods lead to a favorable performance in detection probability, which makes a foundation for exploring usable spectrum for WSN.