Article Abstract:
AT&T has developed the Electronic Messaging System (EMS) for the Summer Olympics in Los Angeles. The system is a network of 1700 terminals, 300 printers, 7000 paging devices, fourteen minicomputers, all connected by 300 miles of light-guide cable. The messaging component of the system is menu-driven with soft keys so that it is easy to use and can be learned quickly. Mailboxes, notice boards, telex, and paging services are available through the EMS. The 3BNet, 10-megabit local area network aids in the monitoring of the entire system. Statistical multiplexors allow the terminals to operate at high speeds for short access times. Use of the UNIX operating system also speeds access times. Television signals are sent from event sites to the International Broadcast Center over the Digital Television Lightwave System on FT3C light-wave lines. Diagrams and a map show the organization of the EMS. Screen displays illustrate the messaging system and the terminals that monitor the system.
User Contributions:
Comment about this article or add new information about this topic:
Article Abstract:
Because of Alaska's vast size and scattered population, the telecommunications satellite serving telephone needs and radio and television broadcasting is important. The Satcom 5 satellite serves widely scattered villages providing entertainment and educational television as well as dial telephone service. Teleconferencing is made possible by the modern network and is used by the legislature and for education. Development is continuing similarly to technologies of developing nations. Maps and diagrams illustrate communication techniques used.
User Contributions:
Comment about this article or add new information about this topic:
Article Abstract:
A new system of emergency alert via satellite will aid in the rescue of passengers and crew members of sinking ships or crashed airplanes anywhere around the world. A small, battery-powered transmitter would be activated in an accident and a low-power omnidirectional signal would be picked up by a satellite. The satellite would relay the signal to an earth station for proper action. Both a polar-orbit and a geostationary system are being studied. Diagrams explain system operation and the generation and reception of distress signals.
User Contributions:
Comment about this article or add new information about this topic: