An energy detection scheme based on hysteresis-threshold for cognitive radio

Cognitive radio system offers opportunistic spectrum access to licensed spectrum and significantly improves the spectrum utilization. Energy detection is a spectrum sensing technology widely utilized to find spectrum opportunities. Based on single-threshold, double-threshold energy detection is proposed to get a better detection performance. But a third state that the received energy locates between thresholds will exist in the double-threshold detection scheme, resulting in the decline of detection reliability. Hence this paper proposes a novel hysteresis-threshold energy detection scheme. Both theoretical analysis and simulation indicate that the proposed scheme outperforms the traditional double-threshold detection algorithm in detecting probability and spectrum utilization, at the cost of an acceptable increment of the collision probability.