The applet shows the effects of RF filter bandwidth, shape and band-center offset on the detected video of a 100 ns RF pulse of adjustable rise-time, pulse shape, and within-pulse frequency modulation.
The upper left display shows the input RF pulse envelope, and the upper right display shows the pulse RF spectrum and the transfer response of the RF filter selected from the Filter Type drop-down menu.
The lower display shows the resulting filtered output pulse envelope.
A second drop-down menu selects the pulse rise and fallback shapes.
The scrollbars control the pulse rise-time, pulse center frequency, FMOP, and filter characteristics. Modification of the pulse and filter parameters affects the output pulse response.
Default values may be modified and the displays updated using the scrollbars or drop-down menus.
Moving the mouse in signal-time and signal-frequency spaces displays the plotted values relative to the pointer x-axis position.

User Notes:
An example offsetting a pulse in frequency by the filter bandwidth shows that time sidelobes are formed aligned with the pulse rise and fall positions; these can be up to –13-dB relative to the pulse peak amplitude.
This shows that for frequency-offset, fast rise-time pulses, considerable pulse energy is contained in the spectral sidelobes, and these are still passed by the filter.
Increasing the pulse rise-time and optimizing the filter shapes reduces spectral sidelobes and in consequence, the magnitude of time sidelobes.