Reliability of CSRS-PPP for Validating the Egyptian Geodetic Cors Networks

Abstract

The development, utilization, and maintenance of continuously operating reference stations (CORS) network are vital in many areas of surveying and geodesy, such as controllinggeodetic networks, developinglocal ionospheric models, and estimating the tectonic plate movements. Accordingly, the Egyptian Surveying Authority (ESA) established a CORS network consisting of 40 stations covering the Nile valley and its delta in 2011. CORS collect global navigation satellite system (GNSS) data. Recently, Egypt has witnessed rapid growth in many infrastructure projects and the development of new cities on a national scale. Therefore, there is an urgent need to investigate the ESA-CORS accuracy; the quality of data from the ESA-CORS must be considered for monitoring continuous tectonic motion, coordinating changes, and for Egypt’s development plan. Contemporary research worldwide identified considerable benefits of the precise point positioning (PPP) solution of dual- or single-frequency GNSS data. This study investigates the reliability of using the CSRS-PPP service for three consecutive observation days of 32 ESA-CORS networks in Egypt and the surrounding six international GNSS services (IGS)-CORS. For ESA-CORS, the PPP solution showed a root mean square error (RMSE) value of 6 mm (standard deviation [SD] = 3–4 mm) in east and north; for the height direction, the solution indicated an RMSE value of 22 mm (SD was about 14 mm). At a confidence level of 95%, this study revealed that SD95% was 2 mm in east and north directions and 6–7 mm for the height direction. This study shows that the PPP solution shown from the ESA-CORS stations is associated with two times better for horizontal and four times for the height direction than the delivered form ESA-CORS stations.

Method of Development of a New Regional Ionosphere Model (RIM) to Improve Static Single-Frequency Precise Point Positioning (SF-PPP) for Egypt Using Bernese GNSS Software

“…For all observation days and all stations, the findings for the east direction indicate an error range of 0.006-0.45 m with an average value of 0.15 m. It can be seen that DOY 202 reported the least errors, while DOY 203 reported the greatest errors due to some data quality problems; more details about the data quality are explained in ref. [36]. This may include factors such as differences in solar activity and ionospheric conditions.…”

“…SA-CORS stations, a locally constrained network solution was produced for the remaining stations; all relevant information regarding the reference solution is provided in refs. [36,37]. Figure 4 shows the IGS-CORS and Egy.…”

“…The possible explanation for losing the observation data is the poor Global System for Mobile Communications (GSM) transfer from CORS stations to the data center in Cairo, as explained in ref. [36]. Table 3 shows the availability of Rinex observation data for the validation stations throughout the study period.…”

“…The possible explanation for losing the observation data is the poor Global System for Mobile Communications (GSM) transfer from CORS stations to the data center in Cairo, as explained in ref. [36].…”

A Review of Selected Applications of GNSS CORS and Related Experiences at the University of Palermo (Italy)

“…Analogously, in Egypt, the Egyptian Surveying Authority (ESA) has established a CORS network consisting of more than 40 stations covering the Nile valley and its delta to assess the quality of ESA-CORS data to monitor tectonic movements. The study analyses the reliability of free Canadian Spatial Reference System Precise Point Positioning (CSRS-PPP) software over more than 30 ESA-CORS claiming millimetric accuracy [29].…”