Novel design for deeply integrated GPS/INS navigation system

In order to enhance the tracking performance and navigation accuracy in high-dynamic and severe jamming conditions, a new deeply integrated navigation scheme of strapdown inertial navigation system/global positioning system (SINS/GPS) based on vector tracking was proposed. This scheme utilized the feedback loop of integrated Kalman filter to replace the independent and parallel tracking loops in traditional receivers, which enabled GPS receivers accomplish the tasks of available GPS satellite signals tracking and integrated navigation information processing synchronously. Vector tracking algorithm was used to enhance the correlations of tracking channels and strengthen the adaptability of changes of carrier-to-noise power density ratio (C/N₀) for tracking channels, so that it could improve navigation performance during brief signal outage. This deeply integrated system treated the Is and Qs measurements as the measurements of the navigation filter directly, which could decrease residual errors of the filter and improve the navigation accuracy and tracking performance of this navigation system. The simulation results indicate that this deep integration scheme based on vector tracking could not only guarantee the navigation precision and reliability of the integrated system during brief signal outage, but also improve perfect tracking performance and anti-jamming capability at low (C/N₀) level.