VBW
Menu Path:
lets you change the analyzer post-detection filter (VBW or “video bandwidth”).
Auto - When checked (default setting), selects automatic coupling of VBW to RBW Resolution Band Width (RBW or ResBW): specifies the minimum frequency bandwith that two separate frequency spectra can be resolved and viewed seperately. For FFT (digital) based VSA's the process is equivalent to passing a time-domain signal through a bank of bandpass filters, whose center frequencies correspond to the frequencies of the FFT bins. For a traditional swept-tuned (non-digital) spectrum analyzer, the resolution bandwidth is the bandwidth of the IF filter which determines the selectivity. using the ratio set by . To decouple VBW from RBW, uncheck this checkbox.
This parameter is only available with Power Spectrum, Adjacent Channel Power and Spectral Emissions Mask measurements.
For Time Input Domain measurements, the VBW value is a desired value that may coerced to an Actual VBW value. The VBW value shown at the bottom of some traces (e.g., Spectrum) is the Actual VBW value (not the desired VBW value).
See Also
