Quantitative Assessment of GNSS Vulnerability based on D-S Evidence Theory

Abstract

With the increasing attention paid to Global Navigation Satellite System (GNSS) vulnerability, there is an urgent need to develop a systemic and feasible approach to weight the GNSS vulnerability degree. A novel model of quantitative assessment for GNSS vulnerability relying on several predefined metrics of vulnerability performance is proposed to measure the impact of vulnerability factors on service availability. This model applies the theory of Dempster-Shafer evidence reasoning to fuse three metrics of vulnerability performance, which are designed carefully to reflect the reliability of service availability in three different perspectives. This model includes three steps: determining performance metrics, calculating vulnerability index and characterizing the vulnerability state of service availability. This approach chooses metrics from the system’s point of view, ignores the more abstract attributes of vulnerability factors but seeks concrete observables, calculates quantitative vulnerability index and provides evolution of vulnerability state over time. Experiments based on GNSS vulnerability physical simulation, verification platform established in our lab show that this method measures the vulnerability index accurately. Moreover, it lays the foundation for future threat inferences and remedy operations under the influence of vulnerability.