ABSTRACT:
GPS-based systems have been widely used in different critical sectors, including civilian, military and commercial applications. Despite of being able to provide great benefits, under certain circumstances they show to be highly vulnerable to intentional interferences. In this context, this article aimed to evaluate the vulnerability range of this kind of systems, focusing on different kinds of environments and based on different propagation models, to which the simulations were performed. Results show high vulnerabilities of GPS-based systems even when operating in a well-protected urban environment, in a short range and under low-power sources of radiation. Graphs are presented with the range of effectiveness for different power levels of jammer in different situations. Evaluations are performed not only for the acquisition but also for the tracking processes of the GPS receivers, therefore being possible to establish a safe operation range for having a trustful GPS signal and mitigate malicious actions. The comparisons allow, as well, highlighting the importance of using the correct propagation model, in order to achieve consistent results, depending on the desired situation.
KEYWORDS:
GPS Receivers; Jamming; Vulnerabilities; Propagation models; Friis equation; COST-231 Hata model
