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Technical Reports

High Accuracy Global Positioning System Test: Phase II

The High Accuracy Nationwide Differential Global Positioning System (HA-NDGPS) is a prototype position location service that uses carrier phase and code measurement data to obtain precise geolocation information. This project was established to assess the feasibility of improving upon the...

High Accuracy Global Positioning System Tests: Phase I

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...