Joint physical network coding and destination aided cooperative jamming for secure wireless sensor networks

In this paper, we investigate physical layer network coding (PNC) and destination assisted cooperative jamming (DACJ) for physical layer security in wireless sensor networks, in which there is one source, one destination, a cluster of intermediate nodes, and multiple eavesdroppers. Under the PNC protocol, the considered two-hop wireless sensor network implements a complete transmission process in two phases. In the first phase, through sending a jamming signal from the destination and exploiting the PNC at the relay, the relay decodes the exclusive-or (XOR) performed form of the source and the jamming message. Therefore, the jamming signal can degrade the wire-tap channels without hampering the legitimate channel. In the second phase, the relay transmits the re-encoded message to the destination while eavesdroppers are out of work as they cannot extract information from the signal. Thus, the proposed design can significantly improve the performance of secure wireless communications. Meanwhile, the proposed schemes select one optimal node from the intermediate nodes and give an optimal solution of power allocation to maximize secrecy capacity. Numerical simulation results show that the proposed schemes have a better and more stable secrecy performance than the conventional schemes at the same power consumption. ? 2016 IEEE.EI2016-Jul