Anritsu MS9740B - Changing Data Capturing Method

4.3 Changing Data Capturing Method
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Changing Measurement Conditions
4.3 Changing Data Capturing Method
The following measurement conditions can be set.
Resolution
This sets the optical wavelength resolution for measuring the optical
spectrum (wavelength resolution determined by built-in grating).
The actual resolution at the Center wavelength can be displayed.
For the resolution and actual resolution, refer to 1.3 “Glossary”.
VBW
This sets the bandwidth of the internal optical receiver amplifier.
A narrower VBW reduces noise. Set a wider bandwidth when measuring
modulated light.
Averaging
This suppresses randomly generated noise. There are three types of
averaging processing: point average, sweep average, and smoothing.
Point and sweep averaging suppress noise by performing repeated
measurements and averaging the results.
● Point average:
Performs measurement for set number of times at each sampling point
and finds average
● Sweep average
Performs wavelength sweeping for set number of times and finds
average from each measured data
The sweep average is calculated by the following formula.
When sweep count < sweep average set count:
When sweep count ≥ sweep average set count:
(
)
( ) ( ) ( )
N
nMnYN
n
Y
+−×−
=
1
1
Y (n):Average value, M(n): Measurement value, N: Sweep average setting
count, n: Sweep count
Smoothing suppresses noise by averaging multiple data in the
wavelength direction.
Two or more average processing can be performed simultaneously.
(
)
( ) (
) ( )
n
nM
nYn
nY
+
−×−
=
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