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

摘要

With the increasing attention paid to Global Navigation SatellitenSystem (GNSS) vulnerability, there is an urgent need to develop a systemicnand feasible approach to weight the GNSS vulnerability degree. A novelnmodel of quantitative assessment for GNSS vulnerability relying on severalnpredefined metrics of vulnerability performance is proposed to measure thenimpact of vulnerability factors on service availability. This model appliesnthe theory of Dempster-Shafer evidence reasoning to fuse three metrics ofnvulnerability performance, which are designed carefully to reflect thenreliability of service availability in three different perspectives. This modelnincludes three steps: determining performance metrics, calculatingnvulnerability index and characterizing the vulnerability state of servicenavailability. This approach chooses metrics from the system’s point of view,nignores the more abstract attributes of vulnerability factors but seeksnconcrete observables, calculates quantitative vulnerability index andnprovides evolution of vulnerability state over time. Experiments based onnGNSS vulnerability physical simulation, verification platform established innour lab show that this method measures the vulnerability index accurately.nMoreover, it lays the foundation for future threat inferences and remedynoperations under the influence of vulnerability.