A Quality Evaluation of Precise Point Positioning within the Bernese GPS Software Version 5.0

Abstract

This study examines the degree of precision of precise point positioning system currently implemented in the Bernese GPS software 5.0 by zero differenced observations. The relationship between the accuracy of PPP and observation duration has been investigated using GPS data from a subset of IGS tracking stations observed over 7 days in different periods of year 2007. In the beginning, short reviews about PPP algorithm principle are given. Then, the results of several processing scenarios are presented and their respective precisions and convergence results are analyzed. Finally, with default parameters, accuracy assessments of PPP solutions are discussed. Investigation results have shown that PPP provides cm-level precision quite easily by using appropriate processing parameters within a few hours of observation. A faster convergence can be available for the north component in any case. The east component requires a convergence period more than two times longer than the north component. The east component provides a better precision than the height component after 2-3 h. For the shorter periods of observation, it is impossible to perform a reliable and accurate positioning with PPP due to the unresolved ambiguity. The repeatability and the precision ratio of the positioning are very low and unreliable for observations of a 5-min period. The mean values of RMS errors are about 0.25-0.30 m for north and east, and 0.5 m for up components. A great improvement can be achieved within a 30-min period, where mean RMS errors of 0.09 cm, 0.04 m and 0.11 m, respectively, in north, east and up were obtained. This precision could be improved up to three to five times by using, respectively, 2-8 h observations. It is possible to obtain at mm to cm-level precision at the end of the 12 h observation for all the coordinate components. Finally, 24 h data processing produced 0.0031, 0.0058 and 0.0088 m RMS errors for the north, east and up components in sequence. For all these cases, north components are more precise than up and east.

The application of Precise Point Positioning in Geosciences

“…Selection of stations used for similar analyses varies from regional [3,10,21] to globally distributed sets of stations [14]. Often, different observation lengths are analysed from, among other lengths, 0.5 hour [14] to 6 days [3].…”

“…Attempts have been made to determine convergence time for accuracy thresholds [cf. [13][14][15]. Decimeter-level accuracy is reached within first hour of observation decreasing exponentially to single centimeters for 12 and 24 hour periods.…”

“…Convergence-time analyses for thresholds of 10, 5, 2 and 1 cm were done by Soycan [14]. The convergence claimed by Leandro [15] is 5 cm with over 2-hour period of observation and a little longer for the height component to approach the same error level.…”

Recent Contributions of Some Fields of the Electronics in Development of Forest Operations Technologies

“…That being the case, enhancing GNSS positioning accuracy is a primary goal and it could be reached by integrating GNSS with other technologies like RTK, RBN DGPS [74], IMU sensors [3], or RF [75]. Using RTK, it is possible to reach centimeter-level accuracy [76]. Moreover, it is possible to have a positioning error below 1 m in forest conditions also by using RBN DGPS [74].…”

Satellite clock stability analysis depending on the reference clock type

“…PPP. In this positioning method, the satellite clock error cannot be deleted by differencing observations, and the knowledge of high-quality clock corrections is extremely important (Kouba and Héroux 2001;Lou et al 2016;Soycan 2011). High-rate PPP measurements are in use in the monitoring of natural and anthropological phenomena such as seismic wave motions (Xu et al 2013), permanent stations monitoring (Maciuk 2016a;Szombara and Maciuk 2017), landslides control surveys (Şanlıoğlu et al 2016) and earthquakes observations (Kaloop and Rabah 2016).…”