A Doppler Reciprocity based Key Generation Method for C-V2X System

In this paper, we design a key generation system based on the C-V2X protocol, which employs the Doppler reciprocity between two vehicles. By exploiting the symmetric measurements of the Doppler frequency offset as the secret source, nodes in vehicular networks aim to obtain identical secret keys. A simulation system is designed using the measured vehicle movement in the Next Generation Simulation (NGSIM) dataset. The effect of the frequency offset of the crystal oscillator is also taken into account. Simulation results show that the proposed Doppler reciprocity based key generation method could achieve a low key disagreement rate (KDR) and good randomness under different vehicular networks scenarios.