Local Atmosphere Augmentation Based on CORS for Real-Time PPP

Real-time precise point positioning (PPP) is mainly limited by the initialization speed. This paper utilizes different local atmosphere augmentation products based on continuously operating reference system (CORS) to improve the convergence time of uncombined PPP, and studies the effects of different atmosphere products on PPP float solution, and then assesses their accuracy and validity of them. The results of the real-time PPP experiments show that, comparing with the traditional PPP, ionosphere products improve PPP convergence time on E (East)-direction significantly, N (North)-direction moderately and U (Up)-direction finitely. Besides, the local PPP ionosphere products based on traditional uncombined PPP (helping improvce 85%, 61%, 18% respectively) are superior to the local smooth ionosphere products based on the geometry-free carrier-phase smoothing code pseudorange method. On the other hand, troposphere products can largely improve U-direction convergence time of PPP by 52%. Moreover, the local PPP ionosphere products and local troposphere products combined PPP has better performance than the single product or other combined products constrained PPP, which improves, the E, N, U directions by 85%, 63%, 69% respectively.