Analyses and Solutions of Errors on GPS/GLONASS Positioning

This paper focuses mainly on the major errors and their reduction approaches pertaining to combined GPS/GLONASS positioning.To determine the difference in the time reference systems,different receiver clock offsets are introduced with respect to GPS and GLONASS system time.A more desirable method for introducing a independent unknown parameter of fifth receiver,which can be canceled out when forming difference measurements,is discussed.The error of orbit integration and the error of transformation parameters are addressed in detail.Results of numerical integration are given.To deal with the influence of ionospheric delay,a method for forming dual_frequency ionospheric free carrier phase measurements is detailed.