NCJ Number
113263
Journal
Security Management Volume: 32 Issue: 8 Dated: (August 1988) Pages: 51-55
Date Published
1988
Length
5 pages
Annotation
In closed-circuit television (CCTV) security systems, fiber-optic cable, compared to coaxial cable, provides low signal loss, immunity to interference, and nonconduction at a relatively low additional cost.
Abstract
The typical system consists of an optical transmitter that converts the signal from a conventional CCTV camera into a corresponding light signal, fiber optic connecting cable, and an optical receiver that converts the light back into a video signal. The transmitter linearly modulates a light-emitting or laser diode either through simple amplitude or through frequency modulation. Transmitters may be designed for stand-alone use or for mounting directly into the camera. The maximum distance fiber optic video transmission can cover is related to the amount of light coupled into the fiber by the transmitter, the signal losses in the cable, and the sensitivity of the receiver. The maximum distance is determined by comparing the published maximum allowable attenuation specification for the entire system with the losses expected between transmitter and receiver. 9 exhibits.