Accessible Requires Authentication Published by De Gruyter June 27, 2008

Reference frames for GNSS positioning services: Some problems and proposed solutions

B. Benciolini, L. Biagi, M. Crespi, A. M. Manzino and M. Roggero
From the journal


Positioning services based on GNSS Permanent Networks (PNs) disseminate the reference frame to users; hence the networks must be adjusted by constraining the ITRF coordinates of some permanent stations (PS), with the satellite orbits and clocks constrained to the values published by the International GNSS Service (IGS). Furthermore, the positioning service provider must use analysis methods, conventions and practices fully consistent with IGS standards. In this framework some problems arise.

A first one is that long term solutions for the IGS PS coordinates are not always fully consistent with weekly IGS products, requiring an appropriate use of IGS PS weekly solutions. Moreover, the consistence of the reference frame implied by different positioning services must be checked, to avoid discontinuities between neighbouring networks. Clearly, in order to monitor the PS coordinates, the adjustment of a network needs to be performed on a quasi real time continuous (daily or weekly) basis. However, from a practical point of view, a continuous update of the PS coordinates is neither appropriate nor possible and alternative proposals will be presented. Finally, most users of real-time positioning services need coordinates in another reference frame, perhaps a local one or the national one. In this case the real-time service provider must distribute the transformation between the broadcasted frame and the user required reference frame.

In this work some possible solutions of the aforementioned problems are presented, based on experiences obtained during data processing and adjustments of the Piemonte and Lombardia (Northern Italy) networks.

Author information: B. Benciolini, Dipartimento di Ingegneria Civile e Ambientale, Università di Trento, Via Mesiano 77, 38100 Trento, Italy
L. Biagi, DIIAR – Politecnico di Milano, c/o Polo Regionale di Como, Via Valleggio 11, 22100 Como, Italy
M. Crespi, DITS – Area di Geodesia e Geomatica, Sapienza Università di Roma, Via Eudossiana 18, 00184 Roma, Italy. E-mail:
A. M. Manzino, DITAG – Politecnico di Torino, II Facoltà Piazza S. Eusebio 5, 13100 Vercelli, Italy
M. Roggero, DITAG – Politecnico di Torino, II Facoltà Piazza S. Eusebio 5, 13100 Vercelli, Italy

Received: 2007-06-04
Accepted: 2007-08-10
Published Online: 2008-06-27
Published in Print: 2008-April

© de Gruyter 2008