Washington, D.C. — Dr. Humphreys briefed the National Space-Based Positioning, Navigation, and Timing (PNT) Executive Committee (EXCOM) Advisory Board on civil GPS spoofing. His presentation, “Spoofing the Timing Signal: What Else is Vulnerable? Understanding Potential Impacts to Infrastructure,” highlighted the Radionavigation Lab’s radionavigation security research including the RNL civil GPS spoofer (video) and a proposal for GNSS message authentication.
Spotlight
Civil GNSS Security Spliter Meeting, September 2010
Background: The Global Positioning System has been a marvelous success over the past three decades. One consequence of this success is a deepening dependence of the civil infrastructure on GPS—especially for timing synchronization. As civil dependence on GPS grows, the potential for financial gain or high-profile mischief combine to make denial or manipulation of GPS a clear and present risk. European researchers and officials are as concerned about GNSS security as their U.S. counterparts. The launch of Galileo will not solve the navigation and timing security problem because, like civil GPS, the Galileo open service—projected to be by far the most commonly used—will be susceptible to jamming and spoofing.
Goals: European and U.S. researchers and interested observers met in Portland, Oregon in Sepetember 2010 to discuss civil navigation and timing security threats and strategize about (1) how policymakers and manufacturers can be persuaded to take these threats seriously, (2) how to identify effective countermeasures, and (3) how to promote adoption of effective countermeasures.
Meeting: Participants and Agenda
Opening Remarks: Todd Humphreys, The University of Texas at Austin
Overview of Vulnerability: Terence McGurn, consultant and PNT EXCOM Advisory Board member
Unique challenges involved in practical civil GNSS security: Todd Humphreys, The University of Texas at Austin
Video: Spoofing a Time Reference Receiver and Phasor Measurement Unit
Proposals:
- Authentication techniques for GPS and augmentation systems: Sherman Lo, Stanford University
- Cryptographic authentication techniques: Logan Scott, LS Consulting
- Interference mitigation techniques: Christoph Guenther, DLR
- Non-cryptographic authentication: Brent Ledvina, Coherent Navigation
Discussion Notes (provided by Brent Renfro, ARL)
Dr. Humphreys Interviewed on BBC Radio Show “The Naked Scientists,” May 2010
Dr. Humphreys talked with the BBC radio show, “The Naked Scientists,” about potential GNSS vulnerabilities.
Helen: So this sounds to me a little bit like when we had computers and we didn’t yet know anything about computer viruses. Almost that there’s a potential for someone to come along and mess around with the GPS and potentially cause some problems. But so far, we’re okay and the idea is that we should be pre-empting those problems
Todd: That’s right and the analogy with computers is a good one. There was a time, perhaps 20 years ago or more when we didn’t have to worry about computer security. But that time has passed and now we’re realizing that we must also pay attention to navigation and timing security.
Remote Sensing
Remote Sensing
Radio-frequency navigation and timing signals can be excellent sources of remotely-sensed science data, revealing structural details of the ionosphere and neutral atmosphere. Perhaps the most promising technique is GPS-based radio occultation (GPSRO), which yields electron density and precipitable water vapor or temperature profiles useful for numerical weather prediction (including space weather). Together with colleagues at UT and Cornell University, we have developed the first software-defined GPSRO sensor suitable for deployment on a cubesat. We have also developed an instrument for ionospheric scintillation monitoring, which leverages our work in software-defined radio and applies techniques we developed for robust GPS signal tracking during scintillation.