In the last decades many new surveying techniques have become available, each characterized by a specific accuracy and field of application. At the same time new complex databases have been developed with the aim to overlay different representations of the territory, in many cases derived from different kinds of survey. Consequently, it grew the need to use for the higher number of applications the same common reference system in order to “speak the same language”. In particular in Italy there is a ministerial decree that states that is mandatory for all the public administrations to use an official reference frame, being it the ETRF2000 at the epoch 2008.0. Therefore, is of the major importance for every surveyor to have methods and infrastructures allowing him to properly refer its coordinates to the official reference frame. In this paper it has been analyzed the way to provide a reliable access to the official reference frame for all those applications where the sub-centimeter accuracy is not requested, whilst one of the most important aspects is the reduction of the time needed for the survey. The PPP technique has been considered, being it one of the most important innovations of the last decades in geodesy, but it has been done under the light of a future use for technical applications, thus considering observing-sessions of few hours (24, 12, 6, 3, 1, 1/2). Being PPP solutions natively aligned to the global reference frame, which is properly linked to the other intra-plate reference frames. Therefor, this technique allows a direct access to all the well defined reference systems for which are known the transformation parameters with respect to the others. Furthermore, despite the longer observation time needed to reach the centimeter level accuracy, PPP may have some advantage in particular in certain remote areas or in particular catastrophic scenarios. Looking at the more classic GNSS applications, have been evaluated the actual precisions that one could reach by using the NRTK technique, and some possible critical issues. After several tests this technique has demonstrated to be a powerful tool that allows to reach few-centimeter accuracy after less than ten minutes of measuring in good working conditions. Nevertheless, NRTK has shown some critical aspects that force not to rely completely on this technique. The passive geodetic reference networks materialized on the ground have been considered as a complement of the NRTK infrastructures to support every kind of GNSS survey, being it done with NRTK or with a classical static post-processing or RTK techniques.
Luca Tavasci (2016). THE USE OF GEODETIC REFERENCE FRAMES FOR MODERN GNSS SURVEYS. Padova : Antonio Vettore.
THE USE OF GEODETIC REFERENCE FRAMES FOR MODERN GNSS SURVEYS
Luca Tavasci
2016
Abstract
In the last decades many new surveying techniques have become available, each characterized by a specific accuracy and field of application. At the same time new complex databases have been developed with the aim to overlay different representations of the territory, in many cases derived from different kinds of survey. Consequently, it grew the need to use for the higher number of applications the same common reference system in order to “speak the same language”. In particular in Italy there is a ministerial decree that states that is mandatory for all the public administrations to use an official reference frame, being it the ETRF2000 at the epoch 2008.0. Therefore, is of the major importance for every surveyor to have methods and infrastructures allowing him to properly refer its coordinates to the official reference frame. In this paper it has been analyzed the way to provide a reliable access to the official reference frame for all those applications where the sub-centimeter accuracy is not requested, whilst one of the most important aspects is the reduction of the time needed for the survey. The PPP technique has been considered, being it one of the most important innovations of the last decades in geodesy, but it has been done under the light of a future use for technical applications, thus considering observing-sessions of few hours (24, 12, 6, 3, 1, 1/2). Being PPP solutions natively aligned to the global reference frame, which is properly linked to the other intra-plate reference frames. Therefor, this technique allows a direct access to all the well defined reference systems for which are known the transformation parameters with respect to the others. Furthermore, despite the longer observation time needed to reach the centimeter level accuracy, PPP may have some advantage in particular in certain remote areas or in particular catastrophic scenarios. Looking at the more classic GNSS applications, have been evaluated the actual precisions that one could reach by using the NRTK technique, and some possible critical issues. After several tests this technique has demonstrated to be a powerful tool that allows to reach few-centimeter accuracy after less than ten minutes of measuring in good working conditions. Nevertheless, NRTK has shown some critical aspects that force not to rely completely on this technique. The passive geodetic reference networks materialized on the ground have been considered as a complement of the NRTK infrastructures to support every kind of GNSS survey, being it done with NRTK or with a classical static post-processing or RTK techniques.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
