Spectrum sensing is one of the most important parts of the cognitive radio system. In order to detect the primary user signal, the robust sensing method is required. In this paper, we propose a combination of the energy detection method and the autocorrelation-based detection method with a cascaded architecture to improve the probability of detection. Energy detection involves lower complexity and energy consumption, but it is unreliable at low signal-to-noise ratios (SNRs). Orthogonal frequency division multiplexing signal property is used by an autocorrelation-based detector, which involves more complexity and is more robust at low SNRs. We build the cascaded design of both energy detection and autocorrelation-based detection to take advantage of each technique. The performance of a cascaded detector is then presented. It is shown that the probability of detection of the cascaded design is always better than the probability of detection of a single detector. The design of the cascaded detector has been implemented which does not require additional sensing time. The complexity and utilization of each detector design is then presented to show the efficiency of the proposed design.

中文翻译：

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一种基于能量和自相关检测的 OFDM 信号高效检测的级联方法

频谱感知是认知无线电系统最重要的部分之一。为了检测主要用户信号，需要稳健的感知方法。在本文中，我们提出将能量检测方法和基于自相关的检测方法与级联架构相结合，以提高检测概率。能量检测涉及较低的复杂性和能耗，但在低信噪比 (SNR) 时不可靠。基于自相关的检测器使用正交频分复用信号特性，这涉及更多复杂性并且在低 SNR 时更稳健。我们构建了能量检测和基于自相关的检测的级联设计，以利用每种技术。然后介绍级联检测器的性能。结果表明，级联设计的检测概率总是优于单个检测器的检测概率。级联检测器的设计已经实现，不需要额外的感应时间。然后介绍每个探测器设计的复杂性和利用率，以显示所建议设计的效率。