The U.S. Department of Transportation (DOT) has unveiled its Complementary Positioning Navigation and Timing (CPNT) Action Plan, which contains steps the department is taking to drive CPNT adoption across the United States transportation system and within other critical infrastructure areas. This plan was mentioned by Robert Hampshire — Deputy Assistant Secretary for Research and Technology and Chief Science Officer, U.S. DOT — during his keynote address at the annual Civil GPS Service Interface Committee (CGSIC) meeting on September 12, at ION GNSS+, which GPS World’s Editor-in-Chief, Matteo Luccio, is attending.
In 2020, the U.S. DOT Volpe National Transportation Systems Center conducted field demonstrations of various PNT technologies that could offer complementary service if GPS is disrupted. The department was able to gather information on PNT technologies at a high technology readiness level that can work in the absence of GPS.
The U.S. DOT have selected 11 candidate technologies to demonstrate positioning or timing functions:
- Two vendors demonstrated low-Earth orbit satellite PNT technologies — one L-band and one S-band;
- two vendors demonstrated fiber-optic timing systems, both based on the White Rabbit Precision Time Protocol;
- one vendor demonstrated localized database map matching database, inertial measurement unit, and ultra-wideband technologies; and,
- six vendors demonstrated terrestrial radio frequency PNT technologies across low frequency, medium frequency, ultra-high frequency, and Wi-Fi/802.11 spectrum bands.
Five of the selected technologies were demonstrated at Joint Base Cape Cod in Massachusetts, and six were demonstrated at NASA Langley Research Center in Virginia. The demonstrations were scenario-based implementations modeled on critical infrastructure use cases under different operating conditions.
Two central recommendations from the demonstration were made: the U.S. DOT should develop system requirements for PNT functions that support safety-critical services; and the U.S. DOT should develop standards, test procedures, and monitoring capabilities to ensure that PNT services, and the equipage that utilize them, meet the necessary levels of safety and resilience identified in recommendation one.
For the full U.S. CPNT Action Plan, click here.
Request for information
The U.S. DOT has also released a request for information (RFI) as one of the steps in driving adoption of complementary PNT services to augment GPS. The department is planning a resiliency test, evaluation, and performance monitoring strategy for PNT-dependent transportation systems.
If any readers are interested in participating, click here for more information.