中文摘要：

鉴于能量检测对信道环境的敏感性，采用理论推导加数值实验的方法，研究认知无线电中衰落环境下的能量检测性能。首先，在等效低通数字域上通过严格的数学推导，给出能量检测的虚警和漏检概率解析式，然后在统计意义上给出了能量检测在瑞利衰落和阴影衰落环境下的检测性能表达式。此外，还在统计意义上，在大信噪比和小信噪比两种条件下对能量检测器的检测概率与观测点数或检测器抽样速率之间的关系进行了分析。最后，在Matlab环境下进行了数值实验，结果表明：在瑞利衰落环境下能量检测器的检测性能明显下降；在阴影衰落环境下能量检测器的检测性能进一步恶化；能量检测器可以通过适当增加观测点数或提高抽样频率来补偿信噪比的下降。

英文摘要：

Owing to energy detection＇ s sensitivities to channel environment, its performances under fading channels are researched by theoretical derivation and numerical experiments. Starting from a derivation of the expressions of false alarm and miss detection probabilities for energy detection, the corresponding ex- pressions are given when in Rayleigh and shadow fading channels. Moreover, the relationships between sig- nal to noise ratio（SNR） and observation points and sampling rates is analysed under the conditions of big and low two kinds of SNRs. Numerical experiments results show that the performances of energy detection decline significantly in Rayleigh fdaing channels and it is further degraded under shadow fading channels and that SNR can be compensated by increasing the observing points or sampling rates appropriately.