The Satellite Positioning Evolution in Coastal
Processes
A. Angrisano1; S. Gaglione1; C. Gioia1; M. Vultaggio1.
1
Department of Applied Sciences - Parthenope University of Naples, Italy
Abstract
In order to guarantee future generations a fair and consistent level of environmental quality is necessary to ensure sustainable development of coastal resources. Adopting a static mode approach towards sea-level rise conflicts with sustaining a dynamic coastal system that responds to perturbations via sediment movement and long-term evolution. In the monitoring of this long-term evolution ancient technologies has played a very important role. Among these the satellite positioning is becoming more and more relevant.
This paper presents a brief survey of the evolution of GNSS (Global Navigation
Satellite Systems) application in coastal processes. The Global Position System
(NAVSTAR GPS) is the best known of these satellite navigation systems. Global
Navigation Satellite System (GNSS) is the standard generic term for satellite navigation systems that provide autonomous geo-spatial positioning with global coverage. A GNSS allows small electronic receivers to determine their location
(longitude, latitude, and height) to within a few metres using the signals as transmitted by the GNSS satellites. In the same process the receivers also calculate the precise time of the signal reception and as such GNSS receivers can be used as highly accurate clocks.
Currently, the United States NAVSTAR Global Positioning System (GPS) is the only fully operational GNSS. The Russian GLONASS is a GNSS in the process of being restored to full operation. The European Union's Galileo positioning system is a next generation GNSS in the initial deployment phase. China has indicated it may expand its regional Beidou (also called COMPASS) navigation system into a global system. India's IRNSS, is also a next generation GNSS.
However, its status and future is unclear as India seems to have entered into a close cooperation with the Russians on the GLONASS system. Satellite
Positioning, for this reason, is very popular and its accuracy can support a large
number of navigation and timing applications. However, it is generally recognized that these systems lacks the accuracy, integrity, and availability to satisfy the more critical applications. This has led to the development of techniques to augment the basic GPS service.
The goal of this paper is to introduce an overview of aforesaid technologies and to present the improvement outcome from their integration (multi constellation) and their augmentation (SBAS – Satellite Based Augmentation Systems) in terms of positioning accuracy, very important in the definition of long-term sediment movement and system integrity.
Keywords: GNSS, Augmentation
1 Introduction
The increasing attention paid to protecting the environment and the consequent need of mapping and surveying areas at risk, such as the coasts subject to erosion and sedimentation, have fostered the use of GNSS (Global Navigation Satellite
Systems) systems in this area. Satellite navigation systems have not only revolutionized navigation, but also geodetic survey. By means of satellite range measurements, it is possible to obtain positioning accuracies previously impossible to obtain, especially for long baselines. With such systems it is possible both the control and the relief of the areas at risk, such as ridges subject to landslides. The advantage of GNSS systems are the simplicity of using them and speed of survey; in addition, along with the suitable augmentation techniques, they offer accuracy comparable to those reached by traditional means of survey.
2 GNSS Systems
2.1 GPS Overview
The Global Positioning System (GPS) is a space-based radionavigation system which is managed for the Government of the United States by the U.S. Air Force
(USAF), the system operator; it is a dual use,
