Symmetricom TimeSource 3100, Руководство пользователя

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TimeSource 3100
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Description
097-72020-01 Issue 9: November 2003
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Antenna
The antenna housing includes a volute antenna, 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.
An amplifier in the antenna provides 23 dB of signal gain.
A downconverter converts the L-band GPS signal to IF for long-distance transport on the
coaxial antenna cable. The antenna cable provides 125 mA power 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, and provides the clock information to
the BesTime Ensemble Timing Generator.
Local Oscillator
A digitally controlled, oven-controlled crystal oscillator (OCXO) develops a highly stable
local oscillator signal, independent of factors that exist outside the shelf. This signal is sent
to the BesTime Ensemble Timing Generator.