Research On Multi-GNSS Precise Point Positioning Technology And Application On The Basis Of RTS Products

With the official launch of IGS real-time stream,contributes the development of GNSS precise point positioning technology,and it has became one of the research hotspots in filed of GNSS precise navigation and position.Because of the effects of network transmission and other uncertain factors,the RTS products is difficult to avoid the existence of interrupt and discontinuity phenomenon,witch hardly affects the discontinuity and accuracy of PPP under consumers' process.Based on IGS RTS products,we develop a series of research about quality analysis and data interruptions distribution of RTS products,next we use IGS sites' data to analyze and verify the accuracy of real-time precise point position.At the same time,we verify the feasibility of pelagic GNSS tidal measurements by using RT-PPP technology.The main researches of the paper focus on the following aspects:(1)Quality analysis on IGS RTS products,include: data availability?data interruptions characteristic and distribution?accuracy analysis of GPS?GLONASS real-time orbit and clock products.(2)Research on RTS products' interruptions repair.From the Angle of the quasi real-time interrupt repair,we repair RTS clock interruptions by three methods include Lagrange interpolation?Lagrange interpolation and cubic spline interpolation,at the same times,analyze and compare the repair result.From the Angle of the real-time interrupt repair,we analyze super short-term forecast factors: initial data length and forecast data length.Finally,we propose a new method “data combine repair” on the basis of study on system error between different RTS products,which make products repair each other,to realize RTS data real-time repair.(3)we choose IGS sites cover all of the world,use IGS products to process real-time GNSS precise point position,verify its accuracy and analyze the convergence time of ambiguity.Position accuracy is test in GPS,GLONASS,combined system real-time precise point position.The horizontal and vertical accuracies about GPS positioning tests are within 3cm and 5cm respectively.The horizontal and vertical accuracies about GLONASS positioning tests are within 5cm and 4cm respectively.The horizontal and vertical accuracies about combined systems positioning tests are within 2cm and 3cm respectively.Based on measurements of the ship,we carry on pelagic GPS tidal measurements by using RT-PPP technology.Tidal measurements results by PPP are compared with results by tide register and their accuracies are 10.64 cm,which verify the feasibility of pelagic GNSS tidal measurements by using RT-PPP technology.