CABLE TRANSMISSION NETWORK BACKBONES COMMUNICATIONS FOR MASS TRANSIT SYSTEM

TO SERVE THE WASHINGTON, D. C. AND NEARBY MARYLAND AND VIRGINIA SUBURBS, A 98-MILE MASS TRANSIT SYSTEM IS UNDER CONSTRUCTION. PROVIDING THE BACKBONE TRANSMISSION MEDIUM FOR THE VARIOUS COMMUNICATIONS FACILITIES IS A CABLE TRANSMISSION SYSTEM, WHICH COMPRISES THE PHYSICAL CABLE PLAN, MULTIPLEXERS, AMPLIFIERS, AND ANCILLARY EQUIPMENT NEEDED TO PROVIDE CHANNELS FOR THE INDIVIDAUL SYSTEMS. FOR FULL REDUNDANCY, EACH LINK EMPLOYS AT LEAST TWO PHYSICALLY SEPARATE CABLES. EMANATING FROM THE CENTRAL CONTROL COMPLEX, TRUNK LINES FOLLOW TRANSIT TRACK ROUTES IN A RADIAL PATTERN, WITH EACH PASSENGER STATION SERVING AS A TERMINAL POINT FOR ITS SYSTEM AREA. THESE CHANNELS WILL PROVIDE HIGH-QUALITY CIRCUITS TO SUPPORT AUTOMATIC SWITCHING CENTRAL OFFICE TELEPHONE EQUIPMENT, LOW- AND MEDIUM-SPEED DATA TRANSMISSION, AND SPECIAL TELEPHONE AND RADIO CIRCUIT APPLICATIONS. ALL MULTI-CHANNEL EQUIPMENT WHICH CAN AFFECT MORE THAN ONE VOICE CHANNEL WILL BE PROTECTED BY REDUNDANT INSTALLATIONS, WHICH WILL BE ON-LINE AT ALL TIMES TO PRECLUDE SWITCHING DELAY IN THE EVENT OF FAILURE. ADDITIONALLY, TEST AND PATCH FACILITIES WILL ALLOW TROUBLESHOOTING AND CIRCUIT RESTORATION. /AUTHOR/

• Corporate Authors:

  Communications Design

  ,    
• Publication Date: 1973-2

Media Info

• Features: Figures;
• Pagination: p. 12-3

Subject/Index Terms

• TRT Terms: Cables; Communication systems; Data communications; Public transit; Redundancy; Transmission lines
• Subject Areas: Highways; Operations and Traffic Management; Public Transportation;

Filing Info

• Accession Number: 00226712
• Record Type: Publication
• Files: TRIS
• Created Date: Aug 5 1981 12:00AM