Primary Activity Awareness Based Secondary Transmission Gains in Smart Sensing CR

Abstract

False alarm and mis-detection probabilities are two major performance bottlenecks on spectrum sensing in cognitive radio (CR) systems. The false alarm leads to throughput loss of the secondary network whereas mis-detection causes interference to the primary network. Another issue with CR environments is that the primary user (PU) activity may change at any moment during the transmission of secondary user (SU) which may cause interference (excluding the interference due to mis-detection). All the aforementioned problems can be addressed if the SU exactly knows the PU’s activity. In this paper, a novel transmission protocol for a multi-antenna SU is proposed to implement smart sensing, where the PU helps SU in obtaining its activity status. Here, the SU gets the exact information of PU’s activity without performing spectrum sensing, therefore, it is expected that the proposed transmission protocol can achieve more throughput since the sensing time overhead and throughput loss due to SU’s false alarm are saved at the cost of paying back to PU for its activity information sharing. Thus, the proposed protocol helps in realizing a smart sensing CR environment by saving the losses that occur due to spectrum sensing. In this work, we have analyzed the performance of the proposed transmission protocol in terms of SU’s average throughput and derived the tight closed-form approximation. Lastly, numerical results validate the analysis and provide insights on the performance gain of our proposed transmission protocol.