I have discrete time series containing signal with smoothly varied frequency over time (called a "sweep"). How can I design a discrete filter (low-pass or band-pass in my case) of a finite length with linearly varying cut-frequency over time and constant cut-slope?
EDIT: the signal is the sampled
"trace" of the seismic source - a seismic vibrator, which sends the vibrations of the slowly varying frequency down the earth. The dependency of the frequency over time (the sweep) is known (let it be linear, $f(t)=f_1*(1-t)+f_2*t)$, but there is a problem that there might be another vibrators that operate on their own, and the task is to
"band-guard" the trace of this vibrator avoiding the unwanted signals from other ones.