COMMUNICATIONS SATELLITES--PAST, PRESENT, AND FUTURE

Growth of commercial satellite communications, following introduction of the geosynchronous type in 1965, has proceeded rapidly. High-frequency systems of up to 30 GHz provide spot beams that eliminate interference to adjacent ground areas so they may use the same frequency bands. Implementation of mobile satellite communications is costly, requiring volume to be very heavy to justify any commercial introduction. Communications carriers will continue to increase the effectiveness with which they utilize present technology; NASA ultimately plans for a high-frequency, large-capacity satellite system with vastly increased capacity, including provision for mobile communications.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/08992029
• Supplemental Notes:
  • Technical Papers presented at General Sessions and Committee Workshops 1980 Annual Meeting Communication and Signal Division, AAR, Washington Hilton, Washington, D.C., August 19-21, 1980.
• Corporate Authors:

  Association of American Railroads

  Communication and Signal Division, 1920 L Street, NW
  Washington, DC  United States  20036
• Authors:
  • Dement, D K
• Publication Date: 1980

Media Info

• Features: Figures; References;
• Pagination: p. 88-96
• Serial:
  • Publication of: ASSOCIATION OF AMERICAN RAILROADS
  • Publisher: Association of American Railroads
  • ISSN: 0899-2029

Subject/Index Terms

• TRT Terms: Artificial satellites; Data communications; Radio; Railroad trains; Telecommunications
• Old TRIS Terms: Train radio
• Subject Areas: Railroads; Vehicles and Equipment;

Filing Info

• Accession Number: 00335561
• Record Type: Publication
• Files: TRIS
• Created Date: Sep 16 1981 12:00AM