In-Band Spectrum Sensing in Cognitive Radio Networks: Energy Detection or Feature Detection?

In a Cognitive Radio Network (CRN), in-band spectrum sensing is essential for the protection of legacy spectrum users, with which the presence of Primary Users (PUs) can be detected promptly, allowing Secondary Users (SUs) to vacate the channels immediately. For in-band sensing, it is important to meet the detectability requirements, such as the maximum allowed latency of detection (e.g., 2 seconds in IEEE 802.22) and the probability of mis-detection and false-alarm. In this paper, the authors propose an efficient periodic in-band sensing algorithm that optimizes sensing-frequency and sensing-time by minimizing sensing overhead while meeting the detectability requirements.