R&S NRP2, Руководство пользователя

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Instrument Functions
R&S
®
NRP2
79 User Manual 1173.9157.02 ─ 03
Edit
Activates the edit mode in the selected field.
The entry can be confirmed with the
↵
MENU or aborted with the ESC/LOCAL key. After-
wards, the table editor is again in the selection mode.
Insert
Inserts a new row containing the values of the selected row.
The maximum table size provides 80 rows.
Delete
Deletes the marked row
Sort
Sorts the rows in the table so that the frequencies in the rows are in ascending order.
Name
Renames the selected table to identify it more easily. Use of the character editor is
described in
​
chapter 3.5.9, "Digit and letter panels" , on page 56.
SCPI command:
​
MEMory:
​
TABLe:
​
MAP
​
on page 252
4.2.3 Filter / averaging
The averaging filter is used to reduce fluctuations in the measurement result to the extent
wanted. Such fluctuations can be caused by inherent noise of the measuring instrument,
modulation of the measurement signal or beats from the superposition of adjacent car-
riers. A more stable display has to be traded off against longer measurement times.
In manual mode, “longer measurement” does not mean that it takes longer to display a
new result, but rather that it takes longer for the result to settle when the power changes.
The filter settings of the "Trace & Statistics" mode and the other modes, which exclusively
provide average power values, differ significantly. The filter dialog box thus displays dif-
ferent parameters depending on the selected display mode. Filtering in the "Trace & Sta-
tistics" mode is described in
​
chapter 4.5.3.3, "Filtering settings" , on page 117.
All average power values are obtained from a three-stage averaging process. First, a
mean value is formed for the acquisition interval given in
​
table 4-2 - either by weighted
or unweighted summation of samples.
A second measurement with reversed polarity of the detector output signal is then per-
formed to suppress offset voltages and 1/f noise of the amplifier. A first result is formed
by subtracting the second measured value from the first measured value. The sequence
of two consecutive measurements is repeated N times. The average value, which is
obtained from the individual measurement results, is output. The number N is the aver-
aging number ("AvgNo"). To obtain a high output data rate, averaging in manual mode
is performed continuously, i.e. a new result is fed into the averaging filter after two
Data acquisition and parameters