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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...

Automated Broken Spike Detection – Phase I

Rail spikes connect railroad rails to the supporting crossties and secure tie plates and crossties together. Recent field inspections and observations have revealed broken spike failures (cut spikes and drive/screw spikes) when used with elastic fastener tie plates in mountainous, high-degree...

Acoustical Warning Devices as Emergency Warning Signals, Phase 2

The Federal Railroad Administration (FRA) sponsored a project to demonstrate the effectiveness of an Acoustical Warning Device (AWD) to be used for generating a secondary Emergency Warning Signal (EWS). The focus of this Phase 2 work is to warn trespassers of an approaching train through the...