Date Added: Apr 2012
Cognitive Radio (CR) technology is one of the strong candidate technologies to solve the spectrum scarcity problems. In this paper, the authors tackle the problem of secure data transmission between a secondary user transmitter and receiver through a relay in the presence of an eavesdropper in a cognitive radio network. The proposed scheme selects the best Decode-and-Forward relay among different relays to assist the transmitter, and to maximize the achievable secrecy rate without harming the primary user. Simulation results show that the secrecy capacity of the network using this scheme will almost be double the capacity when selecting the conventional scheme of relay selection.