In environments characterized by low signal-to-noise ratios (SNR),the traditional double-threshold algorithm applies a fixed threshold, leading to less than ideal detection results. In order to enhance the detection probability while simultaneously minimizing the false alarm probability, an improved energy detector, equipped with an adaptive double threshold (IED_ADT), has been employed. This advanced mechanism allows for dynamic threshold adjustments, optimizing performance under various conditions. By utilizing an adaptive approach, the IED_ADT effectively reduces the likelihood of false alarms, thus ensuring more accurate detection.The detector adjusts the decision threshold based on the Neyman-Pearson criterion, correlates the current decision result with previous and subsequent moments, and then derives a detection probability formula for an improved adaptive strategy under a single-user. Subsequently, it further fuses the decision information from each node to obtain the cooperative spectrum sensing result. Theoretical analysis, accompanied by simulation results, has shown that the IED_ADT scheme, notably, offers superior performance compared to conventional detection algorithms. This is particularly evident in the detection probability (Pd), especially when the signal-to-noise ratio (SNR) is fixed at -8 dB. At this SNR level, the IED_ADT method, which incorporates an adaptive double threshold, significantly enhances detection accuracy, far exceeding the capabilities of traditional algorithms.The optimal improved detection power exponent for this scheme is found to be 2.5.The proposed adaptive double-threshold detection algorithm presented in this paper demonstrates a 72.6% improvement in system sensing performance for a single user, in contrast to the conventional double-threshold detection algorithm under enhanced energy detection conditions. In low Signal-to-Noise Ratio environments, ranging from -5 dB to 2 dB, the proposed adaptive double-threshold detection algorithm significantly outperforms traditional detection methods in terms of detection performance. Similarly, when SNR is below 0 dB and multi-user collaborative spectrum sensing is applied, the fusion decision strategy notably enhances the performance of the IED_ADT detector.No matter whether the “AND” criterion or the “OR” criterion is adopted by the fusion center, the system’s detection performance improves by over 50%.
