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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

High Accuracy Global Positioning System Tests: Phase I

Document Series
Technical Reports
Federal Railroad Administration
Report Number
Subject Positive Train Control
High Accuracy Global Positioning System, HA-GPS, GPS, base station, railroad, Nationwide Differential Global Positioning System, NDGPS, Positive Train Control, PTC, Vital Positive Train Control, VPTC, Differential Global Positioning System, DGPS
HA-GPS Phase I.pdf (2.61 MB)

Transportation Technology Center, Inc. (TTCI) constructed a prototype High Accuracy Global Positioning System (HA-GPS) base station at the Transportation Technology Center (TTC) under contract by the Federal Railroad Administration (FRA) to broadcast carrier code and phase measurement data at 1 kilowatt and 458 kilohertz to remote users to obtain sub decimeter real time kinematic GPS positional solutions within a 200-nautical mile radius. The operation and accuracy of the solution obtained via HA-GPS was successfully tested under a variety of conditions related to railroad operations. 

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Last updated: Friday, May 21, 2021