Getting at the truth

Research output: Contribution to specialist publicationArticle


The article deals with the problem of position authentication. The term 'position authentication is taken to mean the process of checking whether position reports made by a remote user are truthful. Position authentication will be indispensable to many envisioned civilian applications. For example, in the national airspace of the future, some traffic control services will be based on self-reported positions broadcast via ADS-B by each aircraft. The RF carrier broadcast by each GPS satellite is modulated by the coarse/acquisition (C/A) code, which is known and which can be processed by all users, and the encrypted P(Y) code, which can be decoded and used by Department of Defense (DoD) authorized users only. The features for GPS position authentication should be very hard to reproduce and unique to different locations and time. In this case, the authentication process is reduced to detecting these features and checking if these features satisfy some time and space constraints.

Original languageEnglish (US)
Number of pages7
Specialist publicationGPS World
StatePublished - Jan 1 2013


Dive into the research topics of 'Getting at the truth'. Together they form a unique fingerprint.

Cite this