Integrity Monitoring of BDS/INS Loosely Integrated System Using Multiple Kalman Filters

Performance based navigation (PBN) is the fundamental and key part of ATM optimization, which helps to improve ATM safety, increase airspace and fuel efficiency as well as environmental benefits. As one of the navigation performance requirements, integrity monitoring is used to provide timely warning in case of navigation system malfunction or performance reduction. An effective integrity monitoring algorithm for loosely integrated BDS/INS system is presented in this paper, it uses redundant information from two BDS receivers and three INSs to improve the system's integrity monitoring capability. Multiple Kalman Filters are used for integrity monitoring, the integrated system gives out alert and reconstitute Kalman Filters to avoid error propagation in case of one BDS receiver or one INS failure. It is verified by Monte-Carlo Simulations and the result shows that this algorithm can give out timely warning and isolate the abnormal equipment exactly and effectively when a fault happened.