
Associate Professor Todd Humphries (right) and 3 of his students from the University of Texas Radionavigation Lab
We’ve got an addiction to open GPS.
Since the artificial limits were removed from civilian global positioning during the Clinton administration, GPS has become a ubiquitous technology. We use it not just to navigate but to find lost objects, and engineers have integrated it into their work in a host of other ways. Thanks to drone combat, our war machines are also GPS dependent.
Last year, the University of Texas Radionavigation Lab made international headlines by hijacking a drone in front of Department of Homeland Security officials. By sending a fake GPS satellite signal, they were able to trick an unmanned vehicle with false data about its orientation relative to the ground and by doing so make it change direction. This technique is called “spoofing.” On Friday at SXSW Interactive, Associate Professor Todd Humphries of the Radionavigation Lab, along with three of his students, presented their research into spoofing and other extreme forms of GPS.
The ease with which the Lab hijacked a drone — the parts for their device cost only about $1,000 — highlights the serious issues we have with the proliferation of GPS. The FCC restricts broadcasts in the necessary frequency, but that would provide little barrier to a determined criminal; this may have happened already in instances where our drones crashed in foreign countries. Humphries cautioned that while no technique is foolproof, our GPS systems currently have no protections at all. Instead, it would be relatively simple to analyze the timing of messages to calculate how long they take to travel between the satellite and the receiver.
Humphries and his students are also exploring other uses for “extreme” GPS. A potential use of GPS is for augmented reality. In augmented reality applications, a camera or a device like Google Glass shows us an alternate view of reality. This could give us useful data about our surroundings or plunge us into an entertaining game world that interacts with our own. But like other forms of virtual reality, it’s largely been a bust — Humphries quipped that AR has been “disappointing users since 1990.”
Simulating the real world in order to change it is a daunting task. Google Streetview has mapped the world to a startling degree, but this is an order of magnitude simpler than what would be needed to truly map the world in order to create immersive augmented reality, requiring detail down to the centimeter level. Even if you had someone pass through an area using a backpack-mounted camera array, small changes to the area would quickly render the data obsolete.
An alternative under development at the Lab is to combine existing technologies in new ways. A technique called Parallel Tracking And Mapping (PTAM) allows computers to create complex simulations of the space around a user, but isn’t tied into absoute real world location. However, this limitation can be overcome when combined with Carrier Phase GPS — a tool used now only by land surveyors.
Humphries and his students showed off a crude prototype of a device using both. It was about the size of a toaster oven, including a tablet and a bulky antenna, but clearly showed what can be built and developed today. Humphries envisioned most of the rig shrinking down to the size of a phone, though the antenna is difficult to miniaturize. A short video showed a University of Texas rooftop, but with computer generated images of a door and a machine part placed precisely in the world by GPS.
Todd Humphries believes handheld devices are more socially acceptable than wearable glasses-style devices. He suggested that we like knowing when we have someone’s undivided attention. We can tell when our friend or colleague is checking text messages or reading email, but that ability vanishes when the device is always on our face. Instead, he envisioned something more like binoculars or a monocle which we hold up to our face as needed.
More: #HyperGPS Tweets on Storify, curated by Kit
Photo by Kit O’Connell, all rights reserved.




7 Comments

Terrorists. It won’t be long before we see our government go after them for their investigations/interventions. They have the requisite characteristic: they are young and tech savvy. That’s about all the government needs to know.
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Spoofed GPS signals and targeted assasination using drones. What possibly could go wrong there?
Exactly.
I thought there was a secure GPS channel used by the military?
Yes. I am surprised this kind of innovation is not already illegal and persecuted — after all, they publicly pointed out a weak point in our war machine.
I don’t know the answer to this. Evidently the drones were, and still are vulnerable to spoofing whether or not such a channel exists.
Of course the military is aware of GPS spoofing attacks. Of course, they have wargamed countermeasures. But radio is still radio, and it is all-too-easy to just jam the GPS frequencies. Take that, massive drone offensive.