GNGTS 2017 - 36° Convegno Nazionale

GNGTS 2017 S essione 1.2 183 Furthermore, repeatability tests have been made on a single benchmark (installed on the roof of the CRS venue in Udine) to test both reliability and performance of the system (see Fig. 3). LZER0 is still a prototype to be improved and developed but inexpensive and easy to command, useful for research and teaching activities. Acknowledgements We thank Giorgio Durì, Elvio Del Negro, and Sandro Urban for their support in the maintenance of the CRS GNSS networks and Carla Barnaba who managed the bureaucracy inside the Italian national teaching program “Progetto Formativo Alternanza Scuola Lavoro” and found a student for testing LZER0. We thank Massimiliano Chersich and Davide Curone for the support during installation and setup of the Cazzaso GNSS monitoring network. Tab. 2 - IGM 040801 in Palmanova (UD) is an IGM benchmark used as references for the second LZER0 test. The Reference Frame used is ETRF2000 (2008.0), plane coordinates are UTM 33 and the quote is the ellipsoidal height of the benchmark. Differences between the reference coordinates and the LZER0 results (both post –processing mode and real- time RTK) are taken into account. LZER0 RTK coordinates are the average of 5 measures; each of them is taken after the reboot of the RTKLIB module RTKRCV. LZER0 POST-PROC coordinates are the result of a post-processing procedure performed with the Topcon Tools Ver.8.2.3 from Topcon. The Master station is UDI1, 15 km faraway and belonging to FReDNet. For the calculus a 30 min session of GNSS data, sampled at 1 s, has been used. IGM 040801 Palmanova benchmark TYPE NORTH [m] EAST [m] H. ELL. [m] IGM reference 5084917,016 368909,649 71,181 LZER0 POST-PROC. 5084917,015 368909,651 71,256 DIFF. 0,001 -0,002 -0,075 IGM reference 5084917,016 368909,649 71,181 LZER0 RTK (FLOAT) 5084917,113 368909,598 71,346 DIFF. -0,097 0,051 -0,165 Fig. 3 - A Linux tcsh script has been written to repeatedly check the RTK engine inside LZER0. LZER0 during the tests is fixed on a benchmark with well-known coordinates. Every dot represents a single test where LZER0 is forced to restart its RTKRCV module and to reach a final solution within a given timeout. Timeout is 5min and includes not only the RTK search algorithm but also the connection to the RTK service available on the remote server. A green dot is a FIX status representing a correct solution found within the timeout and matching the benchmark coordinates. The yellow dot represents an incomplete solution because of the reached timeout. No false FIX is present. False FIX usually appears when a solution is reached within the timeout but it does not match the right coordinates of the given benchmark. Some statistics are given about the time needed to reach a correct solution.