FAQs from Rohde & Schwarz

How to Measure the Bandwidth of a Transmission Channel


I have to measure the bandwidth of a filter or transmission channel. How can I do this?


In the Spectrum Analyzer mode, you can use several markers and delta markers and find

the bandwidth manually. However, using the "n dB down" marker function is more convenient:

"n dB down" activates the temporary markers that are n dB below the active reference marker.

They are placed to the left and right of the reference marker.

The value n can be entered in a dialog box.

If a negative value is entered, the markers are placed n dB above the active reference marker.

This is the “n dB up” function that can be used for notch filter measurements.