Anritsu MS9740B - Page 200

Chapter 5 Measurement Functions
5-50
If Fitting Span is set outside the screen wavelength range, the ASE
level cannot be calculated.
*2: Masked Span is smaller than Fitting Span.
*3: Pol Loss is used by the polarization nulling method.
● Fitting Span
This sets the target data range for ASE Fitting as the width centered
around the peak wavelength.
● Masked Span
This sets the target data range excluded from ASE Fitting as the width
centered around the peak wavelength.
● NF Select
This selects the NF calculation method.
S-ASE:
The noise figure is calculated from the beat noise between the optical
signal and the ASE.
Total:
The noise figure is calculated from the sum of the following noise
values.
•
Beat noise between optical signal and ASE optical output
•
Beat noise between ASE optical output
•
Optical signal shot noise
•
ASE optical output shot noise
● NF Cal
This sets the calibration factor used at NF calculation.
● O.BPF Lvl Cal
This sets the pass and filter levels for the optical bandpass filter
inserted between the optical amplifier and MS9740B. Set 0 dB when no
filter is inserted or when the characteristics of an optical amplifier
with built-in filter are evaluated.
Light
Source
Optical
Amplifier
O. BPF Lvl Cal
MS9740B
Optical Spectrum
Analyzer
Optical Bandpass Filter