Availability Analysis of GNSS RAIM with Multiple Outliers Based on MUPB

Abstract

The combination of multiple constellations of the Global Navigation Satellite System (GNSS) provides a great possibility to improve the integrity of the satellite navigation. However, with the increase of the number of satellites, the probability of multiple outliers increases. Although a number of studies analyzed the performance of the combined GNSS Receiver Autonomous Integrity Monitoring (RAIM), the analysis of the case of multiple outliers is still lacking. In this paper, a Maximum Undetectable Position Bias (MUPB) scheme based on Bias Integrity Threat (BIT), is used to analyze the horizontal availability of RAIM with multiple outliers. The theoretical background for BIT and MUPB has been analyzed. Next, detailed simulations and analyses with single or combined GPS/BDS (BeiDou Satellite Navigation System)/GLONASS constellations were conducted to evaluate the performance of RAIM. In the simulated scenarios with 70 satellites (GPS 32+BDS 14+GLONASS 24) and 2 or 3 outliers occurring simultaneously, this paper compared the MUPB and the Horizontal Alert Level (HAL) of different aviation approach phases and analyzed the results.