Location Verification Systems for VANETs in Rician Fading Channels

In this paper, we propose and examine location verification systems (LVSs) for vehicular ad hoc networks (VANETs) in the realistic setting of Rician fading channels. In our LVSs, a single authorized base station (BS) equipped with multiple antennas aims to detect a malicious vehicle that is spoofing its claimed location. We first determine the optimal attack strategy of the malicious vehicle, which, in turn, allows us to analyze the optimal LVS performance as a function of the Rician K-factor of the channel between the BS and a legitimate vehicle. Our analysis also allows us to formally prove that the LVS performance limit is independent of the properties of the channel between the BS and the malicious vehicle, provided the malicious vehicle's antenna number is above a specified value. We also investigate how tracking information on a vehicle quantitatively improves the detection performance of an LVS, showing how optimal performance is obtained under the assumption of the tracking length being randomly selected. The work presented here can be readily extended to multiple BS scenarios and, therefore, forms the foundation for all optimal location authentication schemes within the context of Rician fading channels. Our study closes important gaps in the current understanding of LVS performance within the context of VANETs and will be of practical value to certificate revocation schemes within IEEE 1609.2.