In graduation thesis we discusss impacts on GNSS observables. The evaluation is based on results of post processing of GNSS observations. We performed processing of static observations and analyzed them according to different parameters and models used for reduction of tropospheric and ionospheric impact. We used observations from GPS and GLOASS satellite navigation systems. We analyzed the impact of troposphere by comparing post processing results performed with the usage of different troposphere models. We tested the impact of ionosphere with results obtained by processing observations on two different frequencies and by forming linear combination L3. Quality of computed position was tested from according to the observations duration, combined with the use of less precise broadcast ephemeris and precise final ephemeris IGS. We tested also the impact of different cut-off angle combined with PDOP values. All test results are presented and discussed on the basis of coordinate differences between computed and reference coordinates.
|
