Research on Alert Limit of Receiver Autonomous Integrity Monitoring for GNSS Attitude Determination

Two conclusions are given by resolving the equations about the attitude dilution of precision (ADOP) in GNSS Attitude Determination (GNSS-AD) system. One is that the baseline between antennas of is suggested to choose more than 1.5 meters length. Another is that the elevation angle of the reference satellite should be chosen inside (45,50) degrees. Although RAIM is one of the hot research topics today, integrity monitoring and RAIM are mentioned in the position determination system, but they are rarely seen in the literatures about GNSS-AD system. The integrity monitoring Alert Limit (AL) is measured by meter which is fit for position determination. Attitude angle Alert Limit (AAL) measured by attitude angle is proposed which is fit for integrity monitoring of GNSS-AD. The approximate equation which transplants the integrity monitoring alert limit from range to attitude angle is acquired. It can be judged coarsely that the static 1.5 meters baseline attitude determination system loses the integrity when the deviation of attitude angle is more than 0.0082 radian or 0.47 degree.