A Quantization Scheme based on Kullback-Leibler Divergence for Cooperative Spectrum Sensing in Cognitive Radio

Abstract—Cognitive radio (CR) is one of the most promising next-generation communication systems due to its ability to improve spectrum utilization by the detection and the use of vacant channels of licensed users. Reliable detection of the licensed user signal is a pre-requirement for avoiding interference to the licensed user in a CR network. Cooperative spectrum sensing (CSS) is able to offer AN improved sensing performance compared to individual sensing. However, in CSS transmission of raw data from cognitive user (CU) to the fusion center (FC) requires large bandwidth of control channel, long latency and high consumption power. A quantization scheme, in which the raw data can be quantized with few bits at the CU and then be reported to the FC, can solve these problems of raw data transmission. In this paper, we proposed a quantization scheme based on Kullback-Leibler (KL) Divergence for reducing the number of quantization bits while keeping the similar sensing performance to the case that raw sensing data are used. Through simulation, it shown that the proposed scheme can achieve better sensing performance than that of uniform quantization scheme. Keywords-cognitive radio; quantization; Kullback-Leibler Divergence; cooperative spectrum sensing. I