Research On The Carrier-phase Combined Observations Of GALILEO/GPS And Their Applications In The Ambiguity Resolution When Positioning With RTK

With the Galileo system's been constructed,full-operation and the GPS modernization,the future will be a new era which there are many navigation positioning systems syncretized and the function to be more perfect, the service to be more comprehensive, the application to be more popular, the fields involved to be broader.Therefore, the research on the combined observations,it's very significant in the theory and practice when the multi-system satellites will be used to positioning in the future.The paper is mainly composed of some contents, as follows:1) The Galileo system has been introduced in detail and comprehensively, including the Galileo system's composition, the present situation of construction, the parameter design of the system as well as the services the Galileo system provides; And it has made the introduction on the GPS modernization contents. In system parameters and performance, it has compared between the two of the Galileo system, GPS and GLONASS system.2) The functions of the Galileo System Simulation Facility (GSSF V2.11) have been Introduced in detail, And the theories and the methods which the satellite constellation influence the pointing accuracy have been introduced systematically.All kinds of DOP's values have been defined to describe the satellite-geometry intensity factor quantificationally and have been taken as the main evaluating indicators.With the GSSFV2.11 software, the global scale's satellite visibility and all kinds of DOP's values in some day have been simulated, the distribution rule and the distributed curve of the Galileo system's satellite visibility and the DOP's values along with the space and the time have been obtained; And the analyses have been made by comparing with the GPS;when the Galileo system is used to navigate and position ,the number of the visible satellites will be more;the DOP's values will be even smaller; the change is not obvious, and the distribution is even well-proportioned., and it has obtained that the constellation designment of the Galileo system is superior to GPS.3) In the article,the GNSS' observation model and the main error sources and the measures which are used to eliminate or reduce the affect these errors result in have been discussed.The non-difference combined observation and the double-difference combined observation Expressions have been given in single-system and double-system, and it has made the analyses on the corresponding error terms of the combined observations. The criterions which are used to select the combined observations have been listed and some super-performance combined observations have been selected.4) The present situation and the existed insufficiency of RTK has been discussed ; And the current ambiguity resolutions has been summarized; TCAR/MCAR has been introduced in detailjand the TCAR / MCAR method based on the Galileo / GPS carrier-phase combined observations has been researched;and it has obtained some valid combined observations which are used to resolve the ambiguity fast.