Real Time Advanced Receiver Autonomous Integrity Monitoring in DLR’s Multi-Antenna GNSS Receiver

Abstract

The present paper introduces a real-time implementation of Advanced Receiver Autonomous Integrity Monitoring (ARAIM) implemented in DLR’s array antenna receiver “GALANT”. The receiver is capable of tracking multiple frequency measurements both from GPS and Galileo signals. The position, velocity and time (PVT) unit and the Multi- Hypothesis Solution Separation (MHSS) based ARAIM unit are closely coupled and operate in a real-time processing environment within the receiver demonstrator. The presented MHSS based RAIM is extended with Fault Detection and Exclusion (FDE) functionality that can identify large measurement faults in one or multiple range measurements, and adapt its measurement model to mitigate the effects of such biases. Different concepts to obtain such FDE functionality are discussed and compared. A series of measurements using the Galileo Testbed GATE has been recorded and processed in real time using the presented hardware/software platform. Feared event scenarios were generated by introducing biases to one or multiple pseudorange observations on signal level, i.e. at the GATE processing facility. The PVT and integrity results for nominal and feared event scenarios are presented. The ability of MHSS ARAIM to provide a robust navigation solution in the presence of such large faults is assessed and the improvement of positioning accuracy introduced through the application of FDE methods is demonstrated.