NCJ Number
85160
Date Published
1975
Length
329 pages
Annotation
This study investigates applications of satellite communications links of various types for criminal justice usage, with the problems of link and ground station security as the major consideration.
Abstract
The report is the result of a very brief study of several aspects of the transmission of different types of signals via geosynchronous satellites for operation within the continental United States (CONUS) of America. Three basic types of signal channels were considered: color television with one program (sound) channel; 1.544 mbps data rate channels similar to, or identical to the Tl carriers used in the Bell Telephone System; and 50 kbps data rate channels. Five types of satellite transponder models were considered: WESTAR, with uplink at 6 GHz, downlink at 4 GHz with single CONUS beam coverage; proposed future US DOMSAT with uplink at 14 GHz, downlink at 12GHz with multiple spot beam coverage of CONUS; AIS-6 type with uplink at 5 GHz and downlink at 4 GHz with very narrow multiple steerable spot beams; CTS type with uplink at 14 GHz and downlink at 12 GHz with narrow multiple steerable spot beams; and ATS-6 type with uplink at 6GHz and downlink at 2.5-2.6 GHz with multiple spot beams. Several different techniques of transmitting the three basic signal channels were investigated. The report discusses techniques and baseline definitions, satellite transmission studies, and link and station security investigations and gives recommendations. Technical data comprise most of the text. (Author summary modified)