Research On The Troposphere Model And Algorithm Based On Virtual Reference Station

Virtual Reference Station (VRS) technology, is a computer network management technology, Internet technology, wireless communication technology and GPS technology in one, using the most advanced multi-base station network RTK algorithms following the conventional RTK technology represents a new generation of positioning technology after the direction of development. Network RTK with the fundamental principle is that in a certain area (or a city), the establishment of several (three or more) of continuous operation of GPS base station, based on these observed values of GPS base station (due to a long period of GPS base station of observational data, so point and coordinates of high precision), the establishment of the major GPS error model of the region (such as the ionosphere, troposphere, satellite orbit error models, etc.), system operation is that these errors will be observed from the base station by subtracting the value of to form a "no error" of observations, and then use the error-free observations and a mobile station (user - single station GPS receiver) and observations by the effective combination of the mobile station in the vicinity (a few meters to tens of meters ) to establish a virtual reference station and mobile stations and a virtual reference station RTK corrections, real-time RTK. Compared with conventional RTK, the main advantages of this method for wide coverage, high positioning accuracy and reliability, providing real-time centimeter-level positioning, application of a bright future.Papers in the Virtual Reference Station (VRS) system components and principles are introduced, based on the right, including the ionosphere error, troposphere error, track error and other errors, including the major sources of systematic errors were analyzed, focusing describes the troposphere error handling methods and models, and are mainly aimed at weakening the troposphere errors analysis of factors with a station height difference interpolation method to calculate pairs of differential tropospheric delay parameter model, error modeling and separation from the system point of view of VRS technology, the accuracy and reliability are discussed. Comparative analysis of the interpolation error based on an integrated method to calculate the number of differential correction coefficient and the mobile stations by the parameters of initial position accuracy.Experiment a "continuous operation of GPS reference stations in Kunming system" data to calculate the various reference points of the double difference between the baseline tropospheric delay, with a station height difference factor interpolation algorithm pairs of differential tropospheric delay and comprehensive error interpolation, and with the true value to compare the experimental results well verify the correct number generator, error separation, as well as the parameters of validity of the model.