Dsp-based Satellite Positioning Signal Processing Algorithms

Nowadays, although 3D positioning has already been achieved pretty precisely by GPS, it requires the GPS user to track at least four satellites . And the receiver of Beidou Double-star positioning system is active, and user needs to contact with centre station for positioning. So the position of the user is easily to be exposured. And the number of users of Beidou system is limited.Enlightened by TRANSIT and GPS's position algorithm, an algorithm that uses Doppler measurement and PseudoRange measurement to reduce the number of satellites required for positioning is presented in this thesis. By analysing the clock error of receiver particular, a dynamic positioning and measuring speed algorithm is deduced . At last, the PseudoDoppler- PseudoRange positioning algorithm is simulated in GPS and Beidou positioning system respectively. And the simulation results show that the algorithm can satisfy the requirement of positioning precision under certain restrictions.The real time positioning that is assive and continuous can be achieved by applying this positioning algorithm to GPS and Beidou Double-star positioning system. And it be referenced to improve the positioning receivers of GPS and Beidou Double-star positioning system .