Operation of the contemporary permanent GNSS reference station boils down to continuous recording of satellite signals with the set measurement interval at the point with precisely determined coordinates. The recorded observations are controlled, next they are processed and, at the next stage, they are made available to the interested users in the form of various services the basic task of which is to support satellite measurements carried out by means of different techniques and requiring various accuracy levels. KRUR permanent station constitutes an example of a local station making observations of GPS and GLONASS systems satellite signals. It started to operate on 1 November 2009 and it has been in continuous operation since then. The receiving antenna (GPS + GLONASS) is placed on an observation pillar built especially for that purpose in Building C at the Faculty of Environmental Engineering and Surveying of Agricultural University in Krakow. KRUR station is equipped with a multi-frequency and multi-system GPS and GLONASS signal receiver and Zephyr Geodetic 2 antenna. Measurements of satellite signals are made every 1 s. Owing to such continuity of satellite signal measurements, it was possible to set time coordinate series (sequences) with the resolution of 1 h. Such series ...
Surveying devices like tachymeters and levels might be monitored and if it is necessary - calibrated. Similar procedures should apply to GNSS (Global Navi-gational Satellite System) measuring sets. The semi-calibrating research on two GNSS antennas (Trimble 5800) shows that antennas are different and the calibration files have different influence on both. it means that probably individual calibrations files are needed.Antenna calibration and correct orientation of antenna during the GNSS survey may lead to better positions' accuracies. ...
The paper presents the method of testing the precision and accuracy of satellite measurements made with the Trimble NetR9 receiver model with a Zephyr Geodetic Model 2 antenna (TRM55971.00 TZGD), which was additionally equipped with a snow shield. The tests covered the results of static measurements in the form of geocentric coordinates XYZ, calculated with the automatic POZGEO service, operating under the ASG-EUPOS system. The observations were made in measuring sessions of 1h, 2h, and 3h. The statistical tests were conducted to check if the distributions of their errors correspond to normal distribution, which would determine the accuracy of the performed test calculations and measurements, and consequently the usefulness of the tested satellite receiver in geodetic surveys. The correctness tests of the executed measurements and calculations applied three statistical tests: the parametric test, the D' Kolmogorov statistic, and the V and V' Kuiper statistics. The conducted analyses and studies provided conclusions on the correctness of the survey and calculation results and the usefulness of the tested measurement system in the execution of various geodetic operations. ...
Lately we can see a very fast development of the satellite systems created mainly in order to raise the precision, compatibility and interoperation of satellite positioning. Besides functioning American GPS and Russian GLONASS other systems become, like for example Japanese: QZSS (Quazi- Zenith Satellite System), MSAS (Multifunction Augmentation Transport Satellites), Indian: IRNSS (Indian Radionavigation Satellite System), GAGAN (GPS and GEO Augmentation System), Chinese COMPAS, SNAS (Satellite Navigation Augmentation System) or Nigerian NIGCOMSAT (Nigerian Communications Satellite SBAS). The paper shows the results of measuring campaign carried out in Krakow (Poland) on a reference point with the aim to determine reliable accuracy of differential correction in one of SBAS systems - Satellite Based Augmentation System[Narkiewicz, 2003]. Testing control measurements were carried out using simple real-time DGPS procedure in the form of differential corrections from EGNOS system. Carried out detailed analysis of the results let us come to the conclusion, that GMS-2 receiver with EGNOS correction increases the real accuracy of positioningalong the X axis to 2.6m, along the Y axis to 2.1m and the height H to 3.1m. It could then be used to collect data for GIS with possibility of coordinates registration in different reference systems plus making photo documents. ...
