Timing information in wireless communications and optimal location verification frameworks

Abstract

The verification of location information in wireless networks is a relatively new area of research, but one of growing importance. In this work we explore two formal theoretical frameworks for an optimal location verification system in which physical-layer timing information is the main observational input. In our first framework, we derive an optimal decision-rule using the system input/output mutual information as the optimization metric. In the second framework, a more traditional Bayesian approach is adopted in which the misclassification error is used as the decision-rule's optimization metric. A verification-performance comparison between time-of-arrival (ToA) information and the more easily determined received signal strength (RSS) information is given. Our key finding is that for ToA accuracies attainable in next generation wireless networks, significant improvement in location verification can be expected relative to current RSS-based techniques. Our results are important for a wide range of emerging wireless networks and services, but especially for emerging Intelligent Transport Systems (ITS), where the authentication of location information is of critical importance to the safety and security of system users.