R3765/67G Series Network Analyzer Operation Manual
7.4 RESPONSE Block
7-30
The following describes about averaging and smoothing.
(1)
Averaging
In the averaging function, the measured data are averaged with time weight before format-
ting it. Since vector quantity is averaged, there also is an effect that reduces the noise level.
•
Averaging process
(n) : nth averaged data
Y(n) : nth data not averaged yet
N
: Number of times for averaging
(2)
Smoothing
The smoothing obtains the moving average between adjacent pieces of formatted data.
Since scaler quantity is averaged, the noise width is reduced but the noise level will not be
reduced.
•
Smoothing process
(n) : nth format data already smoothed
D(n) : nth format data not smoothed yet
2m
: Smoothing aperture
The aperture for the setting value is obtained using the following equation:
That equation means that the aperture is set by the percentage for the number of the mea-
surement points. Even if the number of the measurement points has been changed, the
setting value of the aperture will be maintained and the aperture <2m> will be calculated
again by the number of the measurement points after the change.
(Example)
Number of measurement points : 101(Point)
Y(n)=
n
n - 1
Y(n - 1) +
n
1
×
Y(n)
Y(n)=
N - 1
Y(n - 1) +
1
×
Y(n)
N
N
(n
>
N)
(n
<
N)
×
×
Y
D(n) =
2m+1
D(n-m) +
• •
+D(n) +
• •
+D(n+m)
D
Aperture<2m> =
( measurement points) - 1
100
<value>
×
2(%)
101-1
100
Measurement points :
n-1
n
n+1
Aperture<2m>=2
Aperture :
Aperture <2m> =
2 = 2
×
