User`s guide

Functions and Measurements 3
N9320A Spectrum Analyzer 41
Decreasing the Resolution Bandwidth
Resolution bandwidth settings affect the level of internal
noise without affecting the level of continuous wave (CW)
signals. Decreasing the RBW by a decade reduces the noise
floor by 10 dB.
1 Refer to the first procedure “Reducing Input Attenuation” on
page 39 and follow steps 1, 2 and 3.
2 Decrease the resolution bandwidth:
Press and
The low- level signal appears more clearly because the noise
level is reduced (see Figure 12).
Figure 12 Decreasing Resolution Bandwidth
A “#” mark appears next to the Res BW annotation in the
lower left corner of the screen, indicating that the resolution
bandwidth is uncoupled.
BW/
Avg
FM
NOTE
The analyzer allows you to change the RBW in a 1-3-10 sequence by
the data control keys. The RBWs below 1 kHz are digital and have a
selectivity ratio of 5:1 while RBWs at 1 kHz and higher have a 15:1
selectivity ratio. The maximum RBW is 3 MHz and minimum is 10 Hz.