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Adaptive Spectrum Sensing Algorithm Under Different Primary User Utilizations

Spectrum sensing is one of the key technologies to realize dynamic spectrum access in cognitive radio (CR) systems. In this letter, a novel adaptive threshold spectrum sensing algorithm is proposed to achieve an efficient trade-off between the detection and false alarm probability. The proposed adaptive threshold algorithm demonstrates a better spectrum efficiency for both primary users (PUs) and secondary users (SUs) in comparison with the conventional fixed one. A closed-from expression between PUs' spectrum utilization ratio and the proposed adaptive threshold is derived and simplified.