Cooperative Spectrum Sensing in Cognitive Radio Network

In Cognitive Radio Network, Co-operative Spectrum Sensing (CSS) plays an important role. In CSS, each Secondary User (SU) submits their results to the Fusion Centre (FC). The FC performs the data fusion and generates a cooperative decision. It uses the hard combining technique to perform this data fusion. In hard combining OR rule, AND rule or maximum voting can be used. The OR rule is conservative, this can raise the false alarm probability. The AND rule is aggressive, this can raise the miss detection probability, and the maximum voting rule works on the majority of the SU result. In these cases, the probability of correct detection of Primary User (PU) signal reduces. To alleviate this problem, we have proposed a weighted strategy fusion decision technique for the FC in this paper. In this technique, the FC decides a weight factor for next sensing slot fusion decision, based on the present and previous spectrum sensing slots performance of the SUs. We compare the result of proposed weighted strategy fusion decision technique, with OR, AND and Maximum voting rule fusion decision techniques; where we found that the proposed technique offers better midway between aggressive AND and conservative OR than the simple Maximum voting rule