Adaptive cubature Kalman filter for ultra-tightly coupled BDS/INS integration

This paper presents an adaptive cubature Kalman filter to improve the adaptivity of ultra-tightly coupled(UTC) BDS/INS (BeiDou Navigation Satellite System/Inertial Navigation System) integrated system against uncertainty involved in process noise statistic. This method adopts the hypothesis testing method to identify the uncertain process noise statistic and introduces a defined adaptive factor into the prediction covariance to decrease the weight of the prior knowledge on filtering solution. It corrects the state estimation in the occurrence of uncertain process noise statistics and avoids the loss of precision for the state estimation without process noise uncertainty. The effectiveness of the proposed method is verified via the simulation of ultra-tightly coupled BDS/INS integrated system.