The Spectrum Application
FPC1000
67
User Manual 1178.4130.02 ─ 02
Therefore you can adjust the color map to the overall shape of the signal you are mea-
suring. Let us say, for example, that the signal has an amplitude range of about 30
dB
with the maximum amplitude at about -80
dBm and the minimum amplitude at about
-120
dBm. With the default settings, the spectrogram is made up exclusively of red col-
ors and it is not easy to distinguish amplitude levels. That is because the purple color
shades are completely out of range.
To get a better result, change the spectrogram reference level to a level near the maxi-
mum power level that has been measured first.
1. Press the "Meas" key to open the measurement menu.
2. Select the "Level Range" menu item to open the level range menu.
3. Select the "Reference Level" menu item.
The R&S
FPC1000 opens an input field to enter the spectrogram reference level.
The reference level should be near the maximum level that has been measured
while the spectrogram was running. In the example, the reference level should be
at about -80
dBm.
4. Enter the reference level you need.
The R&S
FPC1000 now shifts the reference level of the spectrogram to the value
you have entered.
Note that the spectrogram reference level does not affect the
spectrum analyzer itself. In the same way, the reference level of the spectrum ana-
lyzer does not affect the spectrogram. The spectrum trace therefore remains
exactly the same.
Measurements and Result Displays
北京海洋兴业科技股份有限公司（证券代码：839145）
www.hyxyyq.com
