Research On Precise Point Positioning Technology-related Issues

Precise Point Positioning has been become a new GPS technology in recent years. Itcan get same accurate absolute positioning with ITRF，and its precision is close to theprecision of traditional relative positioning model. It processes more simply andefficiency，It has a lot of obvious advantages in many field.This thesis study several key problems in PPP technology，such as quality control ofraw observation data，PPP mathematical model and basic theory，error impact factor，PPP in application，have lucubrate research.The accuracy of precise point positioning is subject to raw observation data，Thisthesis study pre-processing scheme to raw observation data， put forward a newpre-processing flow. In this discuss the impact of result of PPP from the combination ofraw data.In the research of mathematical model，we mainly choose the traditional model，theUofc model，the ambiguity free model to research using theory deduct and exampleanalysis. And discuss in detail to the key problem of PPP－kalman filter.In the research of error impact factor,we mainly study ionosphere delay,troposphericdelay,solid earth tide,ocean tide loading,satellite antenna phase centeroffset,relativity,earth rotation etc factor.Based on the application of PPP, we analyze the positioning results in differentperiods, including centimeter-level positioning capabilities and corresponding thepositioning accuracy. We analyze the main factors affecting the convergence time of PPP,a new strategy derived from robust estimation to improve the convergence time of PPP ispresented. And the positioning results show that robust estimation is effective to improvethe positioning accuracy, especially significant in small span. For non-differentialtechnology advantages in water vapor extraction, by using precise point positioning, thethesis study water vapor extraction algorithm and the corresponding analysis.