Development of multipolynomial, minkowski function based navigation solutions and the analysis of satellite clock and relativistic error impact on the navigation solution for precise position applications

Abstract

The advent of NAVigation Satellite Timing And Ranging (NAVSTAR) Global Positioning System (GPS) based navigation system has revolutionised the field of navigation particularly in the field of civil aviation sector. The GPS is a satellite based navigation system that provides three dimensional (3D) position, velocity and time for users on or above the earth s surface. Position determination using GPS is based on measuring the distance between the receiver and satellites in known orbits. This distance is referred to as the pseudorange. The pseudorange is calculated by multiplying the radio signal velocity (3×108m/sec) with the signal s travel time from the satellite to the receiver. The user s receiver position can be determined by solving the navigation equations which are formed by measuring the pseudoranges from at least four satellites. The receiver position accuracy is the critical parameter in precise applications like aircraft navigation/landings and is dependent on three important factors: i) measured pseudorange accuracy, ii) quality of geometry of the satellites used to solve the navigation equations known as Geometric Dilution of Precision (GDOP) and iii) the type of navigation solution used. The pseudorange accuracy is affected by several error sources such as ionospheric delay, tropospheric delay, clock bias of satellites, receiver to satellite geometry, multipath and the receiver noise.