EXFO IQS-12004B DWDM Passive Component Test System for IQS-500 - Manual (Page 422)

Definitions and Calculation Methods
410 IQS-12004B
Central Wavelength (nm)
The central wavelength is the wavelength at the midpoint between the
lower and upper wavelengths at BW1 dB level from the peak. Note that
the central wavelength is not necessarily the peak wavelength.
Insertion Loss (dB)
The insertion loss (IL) of a filter or multiplexer channel can be described
in many different ways. The DWDM Passive Component Test System uses
the following method to determine the insertion loss:
³
Maximum attenuation within the BW1 interval
The BW1 value you specified will be used as an interval on which the
highest loss will be taken. This is illustrated below:
Increasing loss
Wavelength
0 dB loss line
3 dB
λ
c
IL measured at highest loss
within the defined BW1 region