Spectrum Sensing in Non-Time-Slotted Full-Duplex Cognitive Radio Networks

Compared with conventional cognitive radio networks (CRNs), the efficiency can be improved if secondary users (SUs) have full duplex (FD) communication capabilities. We discuss FD spectrum sensing in non-time-slotted CRNs and study two work modes of SUs, transmitting-sensing (TS) mode and transmitting-receiving (TR) mode. SUs work alternately in two modes. In such a context, we analyze the sensing performance, probabilities of detection and false-alarm, and the SU throughput. An optimal time allocation strategy between TS and TR is proposed. And closed-form expressions of the allocation proportion of TR and TS are provided respectively, as with the detection and false-alarm probabilities. Numerical and simulation results have proved that our strategy can achieve much better performance.