Optimization Of Cooperative Spectrum Sensing With Transmit Diversity And Adaptive Diversity Scheme in Cognitive Radio

Abstract

we have studied and analysed cooperative spectrum sensing in cognitive radio (CR) networks and techniques to
optimize it.the analytic detection results show that the performance of cooperative spectrum sensing is limited by probability
of reporting errors. To deal with this limitation a transmit diversity based cooperation spectrum sensing method is
introduced.
Moreover, we have studied an adaptive diversity scheme with best relay selection. Exact closed -form expressions of
the outage probability of secondary transmissions ,referred to as secondary outage probability, ar derived under the
constraint of satisfying a required outage probability of primary transmission (primary outage probability) for both the
traditional non-cooperation and the proposed adaptive cooperation scheme over Rayleigh fading channel. In addition , we
generalized the traditional definition of the diversity gain, which can notbe applied directly in coginitive radio networks since
mutual interference between the primary and secondary users should be considered. We derive the generalized diversity gain
and show that, with a guaranteed primary outage probability, the full diversity order is achieved using the mentioned
adaptive cooperation scheme.