Credible Positioning of BDS RTK/INS Integration Based on Multi-Information Cross-Validation

The requirement for credible and reliable positioning of a multi-sensor integration system is an essential foundation for comprehensive PNT (Positioning, Navigation, and Timing) services. However, the credibility of positioning results based on multi-sensor integration is difficult to evaluate and even there is no effective mode at present. To try to solve such a problem, a credible positioning model based on the tight integration of BDS Real Time Kinematic (RTK) and Inertial Navigation System (INS) is presented in this paper. In such a model, a multi-information cross-validation algorithm is introduced to ensure the credibility of RTK/INS tight integration. Meanwhile, a backward quality checking model is generated based on the result of the calculated credible positioning error level, which can optimize the positioning results of RTK/INS integration furtherly. After the mathematical model descriptions, a simulated test and a real experiment are adopted to evaluate this presented method. Results illustrated that: 1) envelope level of the credible factor for the real error can reach the centimeter level and the average probability of unenveloped error is within 2%; 2) after applying the quality control scheme based on credible positioning feedback information, the positioning results of RTK/INS integration are improved by 67.6%, 78.9%, and 77.3% on average.