The Surface-Wave Transmission Line and Its Use in Communicating with High-Speed Vehicles

The potential use of surface waves for the communication and control link with high-speed trains is being studied for the U. S. Department of Transportation, Office of High-Speed Ground Transportation. The results are presented for the first part of this study, which dealt with the feasibility of using the surfacewave transmission line (SWTL) as this link, including its characteristics, launching energy onto the line, coupling to and from the line, and communication capacity. The SWTL shows promise in providing the bandwidth and economy required to meet the demands of a high-speed ground transportation system, without requiring the allocation of space in the crowded radio spectrum.