Mark L. Psiaki

GPS jamming is a continuing threat. A detailed understanding of how the available jammers work is necessary to judge their effectiveness and limitations. A team of researchers from Cornell University and the University of Texas at Austin reports on their analyses of the signal properties of 18...more >>

Anomalous behavior of the L1 C/A-code carrier phase has been detected on PRN07/SVN-48. The anomalies are sudden step-like changes of phase by about 10 degrees/5 millimeters. These steps are followed by negative steps of the same magnitude that restore the original phase time history. These...more >>

A portable spoofer implemented on a digital signal processor mounts a spoofing attack, characterizes spoofing effects, and suggests possible defense tactics. GNSS users and receiver manufacturers should explore and implement authentication methods against sophisticated spoofing attacks.

Researchers sought to determine whether the GIOVE-A L1 binary offset carrier signal could be acquired and the PRN codes uncovered using codeless acquisition and statistical signal processing techniques. The short answer: Yes!

Galileo, Europe's answer to the U.S. Global Positioning System, achieved a milestone on December 28, 2005, with the launch of its first test satellite, GIOVE-A, which began transmitting navigation signals in early January 2006. Since the launch, receiver developers around the world have been...more >>