Cooperative Spectrum Sensing Algorithm Based on Date Fusion under Bandwidth Constraints

Cooperative spectrum sensing enables a Cognitive Radio (CR) networks to reliably detect primary users and avoid causing interference to primary user´s communications, and data fusion technique is a key component of it. However, when the number of CR users tends to be large, the bandwidth for reporting their sensing results to the fusion center will be very enormous. In this paper, censoring schemes based on ¿AND¿ rule and ¿OR¿ rule for cooperative spectrum sensing are proposed to decrease the average number of sensing bits to the fusion center. Consequently, the bandwidth is saved efficiently. The performance of spectrum sensing is investigated for perfect reporting channels, imperfect reporting channels with same bit error and imperfect reporting channels with different bit error, and the close formulations are presented. Simulation results show that the average number of sensing bits decreases greatly at the expense of a little sensing performance loss using these two methods, and they both have their own advantages.