CONTINENTAL LAND MOBILE COMMUNICATIONS AND AUTOMATIC POSITION FIXING VIA SATELLITE (FROM CARNAHAN CONFERENCE ON CRIME COUNTERMEASURES - PROCEEDINGS, 1977, BY JOHN S JACKSON - SEE NCJ-57737)

• NCJ Number: 57758
• Author(s): A F BRISKEN; R L FREY
• Date Published: 1977
• Length: 12 pages
• Corporate Author: University of Kentucky
• Publication Format: Document
• Language: English
• Country: United States of America

Annotation

FOCUSING ON GENERAL ELECTRIC RESEARCH AND DEVELOPMENT EFFORTS, THIS ARTICLE EXAMINES THE USE OF SATELLITES IN CONTINENTAL LAND MOBILE COMMUNICATIONS AND AUTOMATIC VEHICLE POSITION FIXING.

Abstract

IN A SERIES OF EXPERIMENTS, THE GENERAL ELECTRIC RESEARCH AND DEVELOPMENT CENTER DEMONSTRATED EFFECTIVE CONTINENTAL LAND MOBILE COMMUNICATIONS AND AUTOMATIC VEHICLE POSITION FIXING TO THE DRUG ENFORCEMENT ADMINISTRATION AND THE IMMIGRATION AND NATURALIZATION SERVICE OF THE U.S. DEPARTMENT OF JUSTICE. A STATION WAGON WAS EQUIPPED WITH A SPECIALLY DESIGNED ANTENNA, A SLIGHTLY MODIFIED COMMERCIAL VERY HIGH FREQUENCY TRANSCEIVER, AND A DIGITAL TONE-CODE COMMUNICATIONS BANDWIDTH RANGING RESPONDER. THE GENERAL ELECTRIC RADIO-OPTICAL OBSERVATORY NEAR SCHENECTADY, N.Y., REPRESENTED THE MAJOR EARTH TERMINAL; A COMMERCIAL VHF BASE STATION WITH A SATELLITE ANTENNA DEPLOYED FIRST IN THE DEA BUILDING IN WASHINGTON, .D.C., AND LATER IN A BORDER PATROL OFFICE IN TUSCON, ARIZ., REPRESENTED THE HEADQUARTERS OR SECTOR OFFICE GROUND STATION. COMMUNICATIONS WERE RELAYED BY THE NATIONAL AERONAUTICS AND SPACE ADMINISTRATION'S ATS-3 GEOSYNCHRONOUS SATELLITE; BOTH ATS-1 AND ATS-3 WERE USED FOR POSITION-FIXING THE VEHICLE. VOICE, SLOW SCAN TELEVISION, AUDIO TEST TONES, INTRUSION SENSOR DATA, AND TELEPHONE PATCHES WERE RELAYED BY THE SATELLITE TO AND FROM THE VEHICLE UNDER A VARIETY OF CONDITIONS IN GREATER WASHINGTON AND THE SOUTHWESTERN U.S. THE EXPERIMENT DEMONSTRATED CONTINENTAL COMMUNICATIONS OF A QUALITY EQUIVALENT TO OR BETTER THAN PRESENT LINE-OF-SIGHT VHF COMMUNICATIONS. DEGRADATIONS IN COMMUNICATIONS WERE OCCASIONALLY OBSERVED WHEN BUILDINGS, MOUNTAINS, BRIDGES, OR TUNNELS OBSCURED THE DIRECT PATH FROM THE VEHICLE TO THE SATELLITE AND IN A NOISY RADIO ENVIRONMENT. VEHICLE POSITIONS TO WITHIN ONE QUARTER MILE WERE ACHIEVED IN REAL TIME AND WITHIN SEVERAL HUNDRED FEET AFTER POSTEXPERIMENT ANALYSIS. TABLES, GRAPHS, MAPS, PHOTOS, AND OTHER ILLUSTRATIONS ARE INCLUDED, ALONG WITH REFERENCES. (AUTHOR ABSTRACT MODIFIED--KBL)