Spotlight

September 2023: “Dr. Todd E. Humphreys, known for his fundamental contributions to secure, precise and robust PNT and GNSS software-defined receivers (SDR), received this year’s Johannes Kepler Award. The Institute of Navigation’s (ION) Satellite Division recognized Dr. Humphreys with this prestigious honor, the highest it bestows, during the ION GNSS+ 2023 conference in Denver.” For more details, visit the Inside GNSS article here, the award page from ION here, or an news article from the ASE department at UT Austin here. A video of the hints given before the recipient was announced can be viewed here. Congratulations to Dr. Humphreys!

September 2023: A paper written by the RNL’s Zach Clements titled “Dual-Satellite Geolocation of Terrestrial GNSS Jammers from Low Earth Orbit” got published in Inside GNSS. “In the past decade, there has been a sharp increase in GNSS outages due to deliberate GNSS jamming. Receivers in LEO are uniquely situated to detect, classify and geolocate terrestrial GNSS jammers. This article explores two-step and direct geolocation of terrestrial GNSS jammers from LEO. In our paper titled “Dual-Satellite Geolocation of Terrestrial GNSS Jammers from Low Earth Orbit” we were able to detect and geolocate over 30 GNSS jammers across Syria, Turkey, Iraq, Ukraine, and Israel with pinpoint accuracy.” The publication, selected as the cover story of Inside GNSS+ in September/October 2023, can be found here.

June 2023: RNL member Zach Clements, Todd Humphreys, and Patrick Ellis from Spire Global were awarded the Walter R. Fried Memorial Award for the best overall paper at the 2023 IEEE/ION PLANS conference. Their paper, titled “Dual-Satellite Geolocation of Terrestrial GNSS Jammers from Low Earth Orbit,” presents a comparison of a two-step geolocation method and single-step geolocation method on data captured over the Eastern
Mediterranean. Congratulations to the authors!

July 2023: A group of 6 students dubbed “DJI But Butter” have been working on improving the RNL’s game-engine by extending the Machine Games demos over the summer. The group, along with an RNL graduate student, took a trip to Houston’s NASA facility to get inspired and stave off summer boredom!

During their visit, they were shown around the internals of the facility, talked to members of the Space Medicine team about how they keep astronauts’ health in check, and got to see the new mission control. Furthermore, they were shown some of the reconstructions of the ISS and space shuttle on the ground, used for training.

March 2023: A paper written by the RNL’s Robert Tenny titled “Robust Navigation for Urban Air Mobility via Tight Coupling of GNSS with Terrestrial Radionavigation and Inertial Sensing” got published in Inside GNSS. “Central to the transportation revolution that will be driven by urban air mobility (UAM) is the problem of robust and secure navigation. Urban environments offer more challenges, such as interference and multipath, when compared to open-sky conditions. As the only positioning system that offers absolutely-referenced meter-level accuracy with global coverage, GNSS will no doubt play a significant role in this revolution. If strengthened against jamming and spoofing, carrier-phase-differential GNSS (CDGNSS), coupled with low-cost inertial sensing, will be nearly sufficient for position, velocity and timing (PVT) needs. But nearly sufficient is insufficient: It is not enough for a UAM PVT solution to offer decimeter-accurate positioning with 99% availability, or even 99.9% availability. UAM will demand that its navigation systems offer decimeter-accurate positioning with integrity risk on the order of 10^-7 for a meter-level alert limit and availability with several more 9s than 99.9%.” The publication, selected as the cover story of Inside GNSS+ in March/April 2023, can be found here.

April 2023: “A vehicular pose estimation technique is presented that tightly couples multi-antenna carrier-phase differential GNSS (CDGNSS) with a low-cost MEMS inertial sensor and vehicle dynamic constraints. This work is the first to explore the use of consumer-grade inertial sensors for tightly coupled urban CDGNSS, and first to explore the tightly coupled combination of multi-antenna CDGNSS and inertial sensing (of any quality) for urban navigation. An unscented linearization permits ambiguity resolution using traditional integer least-squares while both implicitly enforcing known-baseline-length constraints and exploiting the multi-baseline problem’s inter-baseline correlations. A novel false fix detection and recovery technique is developed to mitigate the effect of conditioning the filter state on incorrect integers. When evaluated on the publicly available TEX-CUP urban positioning data set, the proposed technique achieves, with consumer- and industrial-grade inertial sensors, respectively, a 96.6% and 97.5% integer fix availability, and a 12.0-cm and 10.1-cm overall (fix and float) 95th percentile horizontal positioning error.” For a video of the webinar, please visit ion.org.

March 2023: “Todd Humphreys began studying electrical engineering at Utah State University with the intention of becoming a patent lawyer. His career path changed, however, thanks to a professor who told him he had the heart of an engineer. […] A third-generation Aggie, Humphreys completed his bachelor’s and master’s degree in electrical engineering from Utah State. As an undergraduate, Humphreys interned at NASA’s Jet Propulsion Laboratory which sparked his interest in aerospace engineering. […] After graduating from Utah State in 2003, Humphreys went to Cornell to pursue a Ph.D. in aerospace engineering and began studying the new world of GPS. […] In addition to being recognized by UT Austin as an outstanding lecturer, he has received prestigious awards from the National Science Foundation including the CAREER award and the Presidential Early Career Awards for Scientists and Engineers. Earlier this year, the USU Electrical Engineering department named him their distinguished alumnus for the year.” More details found here.

March 2023: A paper written by the RNL’s Zach Clements titled “Carrier-phase and IMU based GNSS Spoofing Detection for Ground Vehicles” got published in GPS World. The summary from GPS World is “we look at how carrier-phase measurements combined with those from an inertial measurement unit can guard against a deliberate attack on an automated ground vehicle — something that cannot be discounted in our world these days.” The publication can be found here.