RICERCA ITALIANA     

Services for the e-Government by satellite positioning

Politecnico di Milano

Abstract

We believe that the item of GPS (GNSS) permanent networks is getting hot at this moment in Italy.
We have therefore decided to make the point on this argument, trying to focus on new themes of research involving both basic and methodological aspects (B) and applications (A) according to the scheme here reported:

B1: strategies and rules for the design of a permanent GPS network
B2: optimisation of data analysis strategies
B3: implementation of the reference frame by a permanent stations network
B4: strategies to model and predict spatially correlated effects
B5: definition of the list of products of the service and of the related quality indexes
B6: optimisation of the exploitation of network data by the users
B7: integration of network data with those of the other sensors (SAR, INS,….)
B8: evolution of the system in view of the implementation of new GNSS

A1: Cadastre updating and problems relative to the assignment of Cadastre to the Communities
A2: creation of a road cadastre
A3: traffic control (car and harbour navigation)
A4: risk prevention and management
A5: implementation of topographic Data Base including positioning data
A6: design and monitoring of structures and infrastructures
A7: location based services

In particular it has to be noted that a new GPS Service is in the implementation phase in the Region Lombardy, for >>>

Principal Investigator

Fernando SANSO' Politecnico di MILANO

Research Objectives

The large worldwide diffusion of permanent networks for positioning from satellite observations (GPS, GLONASS and in future GALILEO) yields to the users community a powerful tool for georeferencing information essential in monitoring the environment and the land use.
Particularly, considering GPS, we distinguish 3 fundamental scales for such networks:
- a global scale (e.g. IGS), on which a global reference frame is defined, essential to understand the global kinematics of the earth
- a continental scale (e.g. EUREF), at which the global frame is more finely implemented and studied
- a local level (e.g. the Swiss AGNES net) that in part contributes to higher order nets and in part is designed to implement the required environmental and land control organized by local government structures
The italian situation is characterized by a particularly fuzzy participation to this global growth; this is also due to the complete lack of a national authority taking care of this matter.
An exception to this situation is given by the Region Lombardy, which in alliance with the Politecnico of Milan is implementing a well designed government network, constituted by 18 receivers fairly homogeneously covering the area of the region; this network is centralized by a data analysis center providing Services to the users. The whole system should be working in a final form by the end of 2004. We hope that such an example will be followed in a well >>>

First Results

Output and Products of Phase 1: the first part of the users handbook will be prepared where existing standard will be described and illustrated with our own practical work. Basically aspect a) and partly aspect b) will be covered.Output and Products of Phase 2: conclusion of the users handbook, including the final optimisation and tuning of existing and new SW, illustrated by the applications to the regional network pf Lombardy (as well as to new permanent networks) and proposed as a new standard for Italy. Implementation of the freeware library for the new SW. This covers the finalization of aspects b) and c) of each research item.

Timescale

24 months

National and international background

A status of the art description of the research must consider four innovations with international relevance:
- Upcoming GPS system modernization with the setup of two new codes in 2005, modulated on the L2 frequency for civil users, and of an additional frequency with the relevant codes in 2007;
- Upcoming GLONASS system restoration, with 18 satellite in 2007 and 24 satellite in 2010;
- Within the decade the constellation of 27 Galileo satellites will be operating, therefore in a generalized manner today we speak about GNNS positioning: Global Navigation Satellite System.
- EGNOS (European Geostationary Navigation Overlay Service) will be completely operating within 2004 and it will improve the horizontal accuracy (95%) from 30 m to 5 m.
This means that positioning precision and accuracy will be improved both in real time (RT) and in post processing (PP), either using differential positioning or precise point positioning (PPP) techniques. Permanent reference stations, or regional (national or sub national) networks of reference stations seem to be less important than in the past; in truth, just for the improvements due to GNSS modernization and for the great spread of positioning techniques, they will assume strategic functions. The reasons of this affirmation must be sought in these two keywords:
- reference frame;
- network products and services with average and wide spread.

Reference frames
One of the >>>