Agilent Technologies 4294A, Operating Manual

Page: 134 / 469

126 Chapter 5
Setting Measurement Conditions
Setting Measurement Accuracy, Stability, and Time
Setting Measurement Accuracy, Stability, and Time
Setting measurement bandwidth
Step 1. Press the
[Bw/Avg]
key to display the measurement bandwidth/averaging menu.
Step 2. Press the
BANDWIDTH [ ]
key to display the measurement bandwidth setting menu.
Step 3. Select the measurement bandwidth.
Step 4. Press the
return
key to return to the measurement bandwidth/averaging menu. Note that
the measurement bandwidth currently selected is displayed in the key label
[ ]
of the
BANDWIDTH [ ]
key.
NOTE Setting a greater measurement bandwidth will improve measurement accuracy, but keep in
mind that this requires a longer measurement time.
Averaging between sweeps (sweep-to-sweep averaging)
Sweep-to-sweep averaging computes each data point (vector value) based on an
exponential average of consecutive sweeps weighted by a user-specified averaging factor.
The sweep-to-sweep uses the algorithm shown in Equation 5-1.
Equation 5-1 Sweep-To-Sweep Averaging Algorithm
where:
Measurement bandwidth Key stroke
1 (measurement speed maximized)
1 FAST
2
2
3
3
4
4
5 (measurement accuracy maximized)
5 PRECISE
Softkey label Selected measurement bandwidth
BANDWIDTH [1]
1 (measurement speed maximized)
BANDWIDTH [2]
2
BANDWIDTH [3]
3
BANDWIDTH [4]
4
BANDWIDTH [5]
5 (measurement accuracy maximized)
A
n
S
n
F
-----
1
1
F
---
–
è ø
æ ö
A
n 1 –
´
+ =