An Approach to Reduce Overhead under the VLQ Transmission Scheme for Cooperative Spectrum Sensing in Cognitive Radio

Weighted Cooperative Spectrum Sensing (WCSS), an important technique in Cognitive Radio (CR), requires all the Secondary Users (SU) to send their sensing data to the Fusion Center (FC) periodically, ignoring the fact that the difference between two consecutive sensing data of the same SU could be small. In order to reduce the overhead transmission in the WCSS, this paper seeks an effective scheme from two aspects. First, a quantization method is introduced to help reduce overhead transmission. To further reduce the amount of overhead, a differential scheme in which each SU sends only the difference between its two consecutive sensing data is proposed. The whole work is conducted under the Variable Length Quantification (VLQ) transmission scheme.