The GPS network

The network consists of a total of 65 vertices (33 from the pre-existing GPS2000 network, and 32 newly monumented), and 190 baselines.

For the entire duration of the survey, two fixed stations were used : CS17 (the ACTV boatyard) and SC07 (the Vesta area), relying on the data acquired from three permanent stations located in Cavallino, Chioggia and Marghera.

The structure of the network, in most cases, has a baseline configured as concentric ellipses. Each vertex is determined by at least four baselines, and by the observations from the permanent stations.

The vertices of the GPS network are metallic footplates designed to allow precision centering in plan, and the measurement of elevation intervals. The device, built out of non-decaying metal, is made of two parts.

The survey of the network was carried out with GPS methodology in static mode, in two independent sessions of about 2 hours each. The measurements were taken using 6 receivers simultaneously, to ensure the creation of several bases at the same time. The operations contemplated the continuous observation of at least 5 satellites during each measurement session, with the instruments programmed for acquisition at 15-second intervals.