Cooperative Antijamming Relaying for Control Channel Jamming in Vehicular Networks

Radio Frequency jamming attacks constitute a major threat to the availability of the vehicular networks. In particular, if the control channel is under persistent jamming attacks, the victim vehicles may fail to receive the safety related messages from the Road Side Unit, which can possibly cause tremendous economic loss and claim human lives. In this paper, we propose a cooperative relaying scheme to circumvent the control channel jamming problem in the vehicular networks, whereby the vehicles outside of the jamming area serve as relays to help forward the received control channel signal to the victim vehicles through another jamming-free service channel. By combining the signals from all relays using the selection combining or maximum-ratio combining methods, the spatial diversity provided by the relays can be effectively exploited to reduce the outage probability of the victim vehicles. Theoretical models are developed to characterize the performance of this cooperative antijamming relaying scheme, which take into account both the large-scale path loss and small-scale channel fading between relaying and victim vehicles under different jamming scenarios. We also propose a relay selection scheme to optimize the performance of the victim vehicles under the relay number constraint. Simulation results are provided to show the performance of the proposed cooperative relaying scheme and relay selection algorithm under different network settings.