Analysis of BDS ARAIM Integrity Support Data Parameters

The realization of the advanced receiver autonomous integrity monitoring (ARAIM) algorithm relies on integrity support data (ISD). To support the use of the BeiDou Navigation Satellite System (BDS) in ARAIM applications, the ISD parameters for BDS are analyzed. Global averages and worst-case signal-in-space ranging errors (SISREs) are computed using data from July 2020 to July 2022. The data cover three open signals: B1I, B1C, and B2a, which are committed for civilian aviation uses. The complementary Gaussian cumulative distribution function is used to bound the SISREs of different signals for all satellites. The results show that the global SISRE values are less than 0.6 m (root mean square) for B1I, B1C, and B2a signals, and the worst-case SISRE can be bounded by a zero-mean Gaussian distribution with a standard deviation of 4.0 m at the 4.0 × 10–5 level. Furthermore, a general discussion of Pconst and bnom is presented, with some recommendations.