NTL Record

Title Excitation of Surface Electromagnetic Waves on Railroad Rail
Record ID 45730
Personal Name
Creator
Goben, C.A.; Davarpanah, M.
Source 65 p. in various pagings
Corporate Creator University of Missouri--Rolla
Publisher United States. Urban Mass Transportation Administration
Publication Date 19780331
Language English
Abstract UMTA's Office of Rail Technology research programs aim to improve urban rail transportation systems safety. This rail-transit research study attempts to develop an onboard, separate and independent obstacle-detection system--Surface Electromagnetic Wave (SEW)--so that rear-end train collisions can be avoided. The use of SEW for communication, control, and obstacle-detection on guided railroad systems is already underway in the United States, United Kingdom, Japan, and Canada. SEW have been sucessfully used on the surface of standard railroad rail and other metallic surfaces. In this report, the preliminary investigation of the propagation properties of SEW on rail surfaces indicates that there exist applications in train-and-obstacle detection. The excitation efficiencies of two types of SEW couplers (prism and grating) are measured as functions of frequency, vertical displacement (h) of the coupler above the rail, horizontal displacement (a) of the coupler from rail center, pitch angle (Phi) of the couler, and yaw angle (Psi) of the coupler. The coupling efficiencies for both prism and grating couplers show a dependence on vertical displacement above the rail; horizontal displacement from rail center, pitch, roll, and yaw angles of the couplers. Measurements of radiation patterns are also made on the two types of SEW couplers in the vicinity of the rail and in isolation at several microwave frequencies. The results of radiation pattern data show that to meet the FCC specification of 500 uV/m at 100 ft from the coupler for 100 mW input, the couplers must be redesigned. The data indicate that both the prism coupler and grating coupler will operate successfully on a moving track-guided vehicle.
Rosap ID dot:9631
Rosap URL https://rosap.ntl.bts.gov/view/dot/9631
TRT Terms Detectors; Detection and identification technologies; Hazards; Navigational obstructions; Crashes; Prevention; Electromagnetic radiation; Electromagnetic waves; Railroad transportation
Classification NTL - RAIL TRANSPORTATION - RAIL TRANSPORTATION;
NTL - RAIL TRANSPORTATION - Rail Safety;
NTL - SAFETY AND SECURITY - SAFETY AND SECURITY
Geographical
Coverage
United States
TRIS Online
Accession No
348804
Report Number DOT-TSC-UMTA-76-19; UMTA-MA-06-0025-77-18
Availability Volpe National Transportation Systems Center, Technical Reference Center
Resource type Tech Report
URL https://ntlrepository.blob.core.windows.net/lib/45000/45700/45730/DOT-TSC-UMTA-76-19.pdf
Format PDF
Database NTL Digital Repository