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Advanced Construction Materials and Technologies
matched the master station used by the MAC. The dual-frequency GNSS receiver used in this work was a Leica GG AX (Hexagon AB, Stockholm, Sweden), mounted on a pole and equipped with an internet-connected mobile phone to receive differential corrections from the selected station through the NTRIP (Networked Transport of RTCM via Internet Protocol) (Lenz, 2004). The Andalusian Positioning Network (RAP) of the Andalusian regional government was used as the active geodetic network.
3. Results and Conclusions.
The reproducibility and repeatability values of the system were determined using three reference antennas in the RAP network (Pozoblanco, Cazalla, Córdoba), applying the UNE 82009-2:1999 standard. Table 1 shows the repeatability and reproducibility values for the different levels tested, in both position and height.
Table 1 - Repeatability and reproducibility values for the six levels tested.
Repeatability Position Height
Reproducibility
Point
Position
Height
1 0.005 0.012
2 0.006 0.017
3 0.005 0.016
4 0.006 0.009
5 0.006 0.010
6 0.006 0.013
0.014 0.031 0.007 0,038 0.007 0,036 0.014 0.045 0.011 0.023 0.013 0.029
0.011 0.034
Average
0.006 0.013
The average planimetry and altimetry results obtained,
reproducibility, allow us to state that the real-time services offered by the RAP network are suitable for use in construction works for engineering projects. In addition, since the base receiver is one of the antennas in the RAP network, this saves both time and money. Time-wise, this process eliminates the set-up period associated with the GNSS antenna that serves as the master. Moreover, since it is only necessary to acquire a single GNSS receiver, the financial costs associated with the work are further reduced.
4. References
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considering repeatability and