The Vector Tracking Based Ultra-tightly Coupled Navigation System And Its Autonomous Integrity Monitoring

With the progress of science&technology,the navigation technology for high-dynamic vehicles now is facing great challenge.Conventional navigation technology cannot fulfill rigorous dynamic requirement for high-dynamic vehicles,or working in a weak signal environment.In this context,the navigation for high-dynamic vehicles in complex battlefield environments has become a particularly intractability problem.One effective method to solve this question is to combined multi navigation systems,such as GNSS/INS integrated navigation,which has been widely used in industry.Among the existing integrated modes,the ultra-tight couple（UTC）mode is completely different with loosely integrated and tightly integrated modes,for the latter are excessive rely on GNSS receiver performance.Ultra-tight couple focus on vector tracking loop and INS aiding tracking technology,which can improve system’s dynamic performance and anti-jamming ability.Although ultra-tight couple navigation system is well researched,there are still only a few research about UTC receiver integrity monitoring,which makes the reliability of receiver cannot be assured.The research of vector tracking based GNSS/INS UTC navigation system have been done in this paper.The main contributions of this research includes:1)Making an improvement of signal tracking loop.2)The design of navigation filter.3)Making an improvement of RAIM arithmetic.The primary research contents are summarized as follows:（1）The mechanism of superior performance for kalman filter based signal tracking loop is derived from noise bandwidth in this paper.An innovative INS state feedback aiding dual-filter based tracking loop is proposed to decouple code and carrier tracking errors.The validity for this architecture is proved by performing simulation test in high-dynamic and lowC N₀ environments.（2）The principle and advantages of vector tracking loop is discussed,and existing UTC scheme is summarized.A suitable UTC scheme is adopted,as well as the navigation filter design is presented.Moreover,a high-dynamic simulation platform is set up in this paper,and the performance analysis of UTC navigation is performed.（3）A code phase discriminator output based novel RAIM algorithm is proposed in this paper,which can be applied to vector tracking loop.The principle and key parameters of this novel RAIM is listed,and sensitivity validate tests are provided.