10
FIBER LINK
2. Introduction
2.1 Description
The Fiber Link supports the transmission of video from a camera to a monitoring
station and a data signal back to the camera over one multimode fiber. A single
coaxial cable at each end of the link is used to connect the appropriate equipment
to the system. In up-the-coax systems, video signals travel in one direction and
control signals travel in the other direction for full-duplex operation. Video is
transmitted from the camera back to the control center over coaxial cable. In
conventional coax systems, signals travel in only one direction at a time. Control
signals to operate the pan-tilt-zoom (PTZ) functions are transmitted from the
control station out to the receiver/driver at the camera station. The Fiber Link is a
single-fiber link that uses two different wavelengths (850 and 1300 nm) for two-way
transmission.
The control signals are transmitted during the vertical blanking period of the
video signal. In addition to video and control, the Fiber Link provides for the
transmission of response signals from the camera station to the control station. It
also provides for transmission of embedded genlock sync if genlocking is a feature
of the particular control system used. It works with all major brands of up-the-coax
systems.
The Fiber Link features extensive LED diagnostics, with input/output indicators
for video, command, response, genlock sync, and optical signal strength.
Table 2-1. Available Models
Model
Enclosure
Fiber
Number
Maximum Wavelength
Type
Size
of Fibers Attenuation
Transmitter
4 x 4 (10 x 10 cm)
62.5µ
1
13 dB
850/1300 nm
Receiver
501R
62.5µ
1
13 dB
850/1300 nm
2.2 Additional Features
• Operating distances of 10,000 feet (3048 m) make possible expanded, simpler
systems.
• Built-in automatic gain control compensates for optical loss within a system.
