Resolution Bandwidth and Time Record Length(Digital Demod)

Resolution bandwidth (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.) depends on the time-record length determined by Result Length and cannot be specified separately. Resolution bandwidth is defined in the VSA according to this formula:

For a more in-depth explanation of how time and frequency parameters are related, see the Understanding Time and Frequency parameters and How ResBW Interacts With Other Parameters topics.

Time Record Length

In the digital demodulator, the time record length is determined as follows (Result Length is in symbols).

For Spectrum, Inst Spectrum, and Time traces:

For other traces: