ADL5303 to measure power transmitted over Fibre Optic Cables

Document created by analog-archivist Employee on Feb 23, 2016
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The project is a hand held tester for a technician in the field, for GPON.
I want to measure the power transmitted over the fiber optic cable, for
Passive Optical Networks. As the transmission may be in the 2.4GHz frequency
range I would like to
know whether the device can directly (without down converting) handle this,
using a photodiode connected to the inputs?


In general, GPON could be TDM-GPON or WDM-GPON.

TDM-GPON signal channel is composed of two wavelength signals: downstream
(1490nm) and upstream (1310nm).

The Dowstream signal is a continuous mode signal. You can use any optical power
meter to measure the signal channel optical power by using an optical coupler.
The Upstream signal is a burst mode signal. You may not be able to monitor the
burst mode signal power with a normal optical power meter. In this case, your
power meter receiver should be fast to detect each burst frame average optical
power. So a special design is needed for this application.

WDM-GPON uses individual wavelength to communicate between the CO to each
of thesubscribers. In this case, normal optical power meter should be no
problem at
all. Somehow, you need to know which wavelength you are interested in when you
measure the channel signal power.