U.S. Investigating Spoofing

 - September 2, 2012, 2:34 AM

While the Iranian capture of the Sentinel caught public attention, it also allowed researchers to show that spoofing technology has been, and continues to be, closely investigated by a number of military and civilian facilities in the United States.

Probably the leading–or at least the most public–GPS spoofing research center in the U.S. is at the University of Texas at Austin. In April, in response to a Department of Homeland Security (DHS) invitation, a University of Texas team took a commercial unmanned helicopter of the type used by police departments to the DoD White Sands, N.M. proving ground, along with the University’s GPS spoofing system. The helicopter was equipped with an autoflight system directed through GPS inputs, but with a manual control override.

The spoofing equipment was set up about a half mile from the helicopter, which was then launched and set to hover via its autoflight system at 50 feet above the ground. The spoofer was activated and it aligned its signals with the true GPS signals, although at lower power. The researchers then increased the false signal power to capture the helicopter’s autoflight system and at the same time electronically “lowered” the false net of signals now surrounding the helicopter. To its now false GPS driven autoflight system, this indicated that the helicopter was rapidly climbing above its assigned altitude, and the system promptly lowered the helicopter’s nose into a rapid descent, which was arrested 10 feet above the ground by use of the manual control override.

While nowhere near as advanced as the Iranian Sentinel capture, the demonstration suggests that with additional funding, anti-spoofing investigations should expand dramatically.

At press time, the DHS had not issued its comments on the White Sands demonstration, but two straws in the wind suggest that the department may still be unconvinced that, despite the evidence of the Sentinel capture and the University of Texas demonstration, aircraft spoofing and capture is an area it wants to get into. The first straw was a comment made to AIN by a UAS industry manager that DHS officials expected that the U of T White Sands demonstration would fail, which perhaps underlines the lack of any positive statements from the DHS at the time. But the second straw was more significant. A Congressional House Committee on Homeland Security meeting on July 18 was called specifically to hear testimony from University of Texas chief investigator Todd Humphries on his work, including the White Sands demonstration, plus other industry witnesses. But there was no DHS testimony offered to the Committee.

Nevertheless, the Iranian Sentinel capture appears to have energized congressional legislators, and substantially increased funding is expected to be allocated to those government and industry groups currently engaged in spoofing research.