Session A2: Next Generation Satellite Navigation Technology

Combining Galileo’s Assisted Commercial Authentication Service (ACAS) with Vestigial Signal Search for Good Protection
Jon Winkel, Independent Consultant; Ignacio Fernandez Hernandez, European Commission; Cillian O'Driscoll, Independent Consultant
Location: Seaview Ballroom
Date/Time: Wednesday, Jan. 24, 11:48 a.m.

Peer Reviewed

Combining Assisted Commercial Authentication Service (ACAS) with additional algorithms, in particular Vestigial Signal Search (VSS), and processing in the receiver, significantly enhances the defenses against advanced spoofing attacks, including any form of meaconing. This paper compares two VSS strategies applied to Galileo ACAS. In the first one, the vestigial signal is searched across all the uncertainty period, defined by the receiver loose time synchronization parameter, which can go up to several seconds. In the second strategy, the vestigial signal is searched over a 4-ms period of uncertainty, corresponding to one E1-B/C code, and then handed over to E6.