Interference Avoidance Based Multiplex Channel Scheme in High-density C-V2X

For disseminating safety warning messages, the terminal on board needs to multiplex the cellular channel to establish the temporary links in high-density C-V2X. Then, the potential co-channel interference will degrade the performance metrics in the high-density scenarios. In this paper, the terminal on board detects the channel status in single slot early using the energy detection method for multiplexing the channel with interference avoidance. Based on the detection result, the base station can estimate the channel idle status in all slots using the hidden Markov model. And the channel list with idle rate is created according to the defined interference avoidance index. The terminal can multiplex the channel with maximum interference avoidance value as the connection link between the vehicles. Finally, the performance metrics which come from the co-channel interference, the blocking rate of H2H links and the outage probability of V2V links, are derived and analyzed in theory. Simulation results show that the proposed scheme has the minimum interference impact compared with the competition access scheme and interference control scheme.