Secrecy Performance Analysis of Cooperative Cognitive Radio Networks with Non-colluding Eavesdroppers

Cooperative cognitive radio networks (CCRNs) are a kind of promising network architectures which can effectively improve spectrum utilization, coverage range and system throughput. However, they are vulnerable to eavesdropping attacks due to the additional transmission of the transmitters’ confidential information at the relay. This paper analyzes the secrecy performance of a CCRN cooperated by a decode-and-forward (DF) relay in the presence of randomly distributed non-colluding eavesdroppers. Based on a system model, we derive expressions of the secure connection probability (SCP) for both direct transmission (DT) and relay transmission (RT) protocols. The lower bound expressions on SCP are further deduced. Simulation results illustrate the impact of network parameters on SCP for both DT and RT protocols and reveal the condition for relay transmission in terms of the source-destination distance.