On/Off-Osnr Method; Challenge; Principle Of "On/Off-Osnr Measurement; Setup - Viavi 8100 V2 Series User Manual

2 Move the cursor on to the channel that is to serve as the reference.
3 Press the
The results are recalculated with respect to this channel of reference.

On/Off-OSNR Method

Challenge

This is a precise out-of-service method used for measuring the in-band OSNR of stan-
dard and also of polarization-division multiplexed (PDM) systems.

Principle of "On/Off-OSNR Measurement"

The On/Off-OSNR method is based on measuring the noise power when the transmis-
sion channel is switched-off.
This is a 2 step method:
1 Switch-on all channels and perform a standard WDM measurement
All parameters like power (P
instrument
2 Switch-off the channel carrying PDM signals and perform a second measure-
ment
The channel power measured at the deactivated channel wavelength will indicate
the in-band noise P
In-band OSNR is calculated based on P

Setup

Select 'Measurements Mode' = OO-OSNR'
Figure 147 OSA Setup: OO-OSNR configuration
Set Ref. Channel
on
= noise power
off
User Manual
Chapter 8 Optical Spectrum Measurement
key.
) and wavelength are measured and stored in the
and P
on
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On/Off-OSNR Method
off
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