I would like to take a time series of several spikes or narrow Gaussians and bandpass using an ift/ifft together with a frequency domain mask to create a series containing band-limited spikes. This is pretty simple but I have an additional desire - that the resulting band-limited spikes are causal - that is each band limited spike has a sharp onset (at the position of the original spike) followed by a tail dependent on the bandpass parameters.
The ultimate goal is a series that looks superficially like a superposition of a multitude of earthquakes.
Is there a simple way to do this?
Thanks very much for any guidance.