Development of GNSS Position Accuracy Simulation System (GPASS) Using 3-D Building Maps, Signal Propagation Model and Receiver Correlator Model

摘要

Current navigation systems provide position information using GNSS, of which position accuracy is gradually improving by the developments of receiver algorithm and antenna performance. However, the GNSS accuracy is very limited in dense urban areas because the signals are blocked, reflected, or diffracted by buildings. This paper describes the development and validation of GPASS (GNSS Position Accuracy Simulation System) that can simulate GNSS position accuracy for dense urban areas using 3-D building maps, signal propagation model and receiver correlator model. The feasibility tests of our system were carried out for the area around the Tokyo Metropolitan Government Building famous for its skyscrapers, and a good agreement was observed between the simulation results and in-situ data. The GPASS is expected to enable the evaluations of navigation serviceability on the spatial and temporal basis, which will be a useful reference for improving the service quality.