GNSS augmentation

About: GNSS augmentation is a research topic. Over the lifetime, 2478 publications have been published within this topic receiving 28513 citations. The topic is also known as: SBAS & Satellite Based Augmentation System.

Satellite clocks characterization and monitoring for global navigation satellite systems

Abstract: In Global Navigation Satellite Systems (GNSS) the user's position is determined measuring the time of flight of the signals broadcast from satellites, which is proportional to the distance between the user and each satellite of the constellation. Time and frequency metrology has an essential role in satellite navigation systems: since a distance can be measured from a time, any error on the measure of time leads to an error on the user's position. Hence, it is fundamental to have precise and stable atomic clocks on board satellites. Therefore the on board clock behaviour has to be continuously monitored and any malfunctioning has to be detected immediately to ensure the adequacy of the timing system to the positioning service and users' needs. This paper will describe the main methodologies for characterization of onboard clocks and their implementation in a robust software developed at INRIM and also used in the framework of the European project Galileo.

Security considerations in the design of tamper resistant GNSS receivers

Abstract: The evolution of Global Navigation Satellite Systems (GNSS) will see the introduction of new security services both in the civil and military domain. The threat of attacks against GNSS such as spoofing has lead to the design of GNSS signals and receiver technologies that attempt to address the problem both at the signal, data and receiver level. In particular, it is expected that modern GNSS will provide both in the civil and government domain access control to the signal through spreading code encryption or access control and/or authentication at the navigation data level. This will require the support on GNSS receiver for secure cryptographic keys and the implementation of security functions. The different security functions are identified and explained. The paper reviews a number of vulnerabilities of these security functions, and provides a number of design considerations in order to mitigate these attacks.