Abstract
Recently, security and energy efficiency for wireless communication has attracted great attention due to the economic, environmental and military concern. We investigated the secrecy capacity and energy efficiency of the wireless cognitive radio networks (CRNs) in the presence of multiple primary users and multiple malicious eavesdroppers. The secrecy capacity and energy efficiency of the CRNs have studied, where the primary and secondary users cooperate with each other. Especially we proposed a system model to enhance the secrecy capacity and energy efficiency. We proposed a cooperative model, in which the secondary user acts as both a relay node to relay packet for the primary user and a jammer against the eavesdropper to create artificial interference. For the relay selection, we used a relay selection algorithm to enhance the energy efficiency of the network. To further improve the secrecy capacity of the network, we used the cooperative jamming technique and proposed an algorithm to interfere the eavesdropping channels. The validity of our proposed algorithm is investigated through simulation, and it significantly increases the energy efficiency and the secrecy capacity of the networks.