New Techniques to Enhance the Performance of Stand-Alone GNSS Positioning

This paper focuses on performance enhancement for stand-alone Global Navigation Satellite System (GNSS) positioning. To speed up the realization of satellite position, a novel technique is proposed for GNSS satellite orbit fast fitting, which contributes to the acquisition of GNSS satellite signal deeply. The ephemeris orbit model is imminent by different fitting algorithms and polynomial interpolation is utilized for the purpose. Moreover, Lagrange and Hermite polynomial are compared for orbit approximation. It is here extended by integrating Weighted Least Squares (WLS) method to achieve GNSS position estimates. We creatively make full use of real-time signal quality for weighted matrix estimation in WLS. Moreover, detailed analysis of satellite geometry distribution is given to ensure the receivers robust navigation. Theoretical analysis and simulation results demonstrate that the proposed techniques yield a significant enhancement in stand-alone GNSS positioning.