Secure and Privacy-Preserving Physical-Layer-Assisted Scheme for EV Dynamic Charging System

Dynamic charging system will enable moving electrical vehicles (EVs) to charge their batteries through magnetic induction by charging pads (CPs) placed on a portion of the roadbed. To realize such a system, the EVs need to communicate with the various parts of the system that include a bank, a charging service provider (CSP), road side units (RSUs), and CPs. In this paper, we propose a secure and privacy-preserving physical-layer-assisted scheme for dynamic charging systems to secure payment and authentication and also preserve the drivers' location privacy. We develop an efficient hierarchical authentication scheme that considers the scalability nature of the system. Efficient cryptosystems are used to authenticate the EVs to the bank, CSP, and RSUs, but our evaluations indicate that the contact time of fast moving EVs and the CPs is too short to exchange multiple messages and execute time consuming operations. Therefore, we develop an efficient physical-layer-based authorization scheme that utilizes autocorrelation demodulation and hypothesis testing to enable the CPs to identify and charge the authorized EVs. Through extensive analysis, simulation, and practical experiments, we demonstrate that the proposed scheme is secure against the considered attacks and can achieve fast authentication and high authorization rate. Moreover, the proposed scheme can achieve full anonymity where no entity or even colluding entities can know the drivers' locations.