本地监测系统可以增强卫星导航系统的性能以满足航空用户的需求。针对目前单接收机本地监测系统在进近着陆应用中各导航性能存在的不足,提出了一种基于多接收机的本地监测系统完好性监测算法。该算法考虑了地面接收机故障对用户安全造成的影响,从而提高了系统的完好性。另外,该算法通过利用既有的增强系统完好性信息,改善了系统对本地差分修正误差的监测能力;并且通过使用卫星信号双频观测量,提高了用户的观测精度。上述优化可有效降低保护门限值,最终达到提高系统可用性的目的。应用该算法增强北斗卫星导航(区域)系统,可在我国及周边地区满足I类精密进近的性能指标要求,并且平均可用性达到95.57%。
The Local Area Monitor can significantly improve the performance of GNSS, and meet the require- ment of aviation users. A Range-Domain Integrity Algorithm of Multi-receivers Local Area Monitor is proposed for the significant challenge in using single receiver. This algorithm monitors the one-receiver-fauh condition, to achieve the integrity requirements. Then it simultaneously reduces the local monitoring biases leveraging the error estimate of the augmentation system and the user confidence values using the dual-frequency signals, in order to ob- tain the minimum protection level and reasonable availability. Finally, the algorithm is applied to evaluate the per- formance of BeiDou Navigation Satellite (regional) system for CAT I precision approach and landing, and the simu- lation suggest that it can provide acceptable availability of 95.57%.