Symmetricom TimeSource 3600, Manual

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TimeSource 3600
S S S S S S S S S S S S S S S S S S S S S S S S S S S S S
Antenna
The antenna types include a roof antenna, mechanical window
antenna, self-adhesive window antenna, or wall antenna. All
antennas include a GPS receiver, amplifier, and intermediate-
frequency (IF) downconverter.
The GPS Receiver extracts a clock signal from the GPS satellite
signals. The receiver can process the signals from all satellites in
view, while simultaneously using the Earth location of the receiver
and other factors to determine an accurate clock signal.
The downconverter converts the L1-band GPS signal to IF for
long-distance transport on the coaxial antenna cable. The antenna
cable provides current from the shelf to the antenna, and
transports GPS satellite IF signals from the antenna to the shelf.
IF Interface
An IF interface accepts the signals from the antenna/IF converter,
and provides the clock information to the BesTime Ensemble
Timing Generator.
GPS Receiver
The GPS Receiver continuously tracks up to eight satellites, using both
carrier and code lock. The recovered pseudo-range measurement data
is processed to determine precise time and frequency state estimates
for the local oscillator. The receiver software is optimized to track and
update state estimates, when as few as one satellite is in view.
Local Oscillator
A rubidium oscillator, based on a digitally controlled servo-loop,
provides an ultra-stable local oscillator signal, which is sent to the
BesTime Ensemble Timing Generator.