Cognitive Radio Primary Network Secure Communication Strategy Based on Energy Harvesting and Destination Assistance

Cognitive radio primary network secure communication strategy based on secondary user energy harvesting and primary user destination assistance is investigated to guarantee primary user secure communication in cognitive radio network. In the proposed strategy, the primary network selects the best secondary user to forward the traffic from a primary transmitter (PT) to a primary receiver (PR). The best secondary user implements beamforming technique to assist primary network for secure communication. The remaining secondary transmitters harvest energy and transmit information to secondary receiver over the licensed primary spectrum. In order to further enhance the security of primary network and increase the harvested energy for the remaining secondary users, a destination-assisted jamming signal transmission strategy is proposed. In this strategy, artificial noise jamming signal transmitted by PR not only confuses eavesdropper, but also be used to power the remaining secondary users. Simulation results demonstrate that, the proposed strategy allows secondary users to communicate in the licensed primary spectrum. It enhances primary network secure communication performance dramatically with the joint design of secondary user transmission power and beamforming vectors. Furthermore, physical layer security of primary and secondary network can also be guaranteed via the proposed cognitive radio primary network secure communication strategy.