Hi @Dogmus, welcome to the forum 
It’s not clear what you’re asking here.
Our 1 dimensional echosounder devices communicate with the ping1d message set of the ping-protocol. The profile data is already somewhat filtered from the raw voltages that are measured by the ADC, but that’s primarily for getting cleaner intensity estimates at each distance range within the profile.
You’ll note that the profile message also includes a distance field, with a corresponding confidence estimate (which can alternatively be retrieved using the distance_simple message), which correspond to the sonar’s internal estimate of the distance to the main object/surface that’s reflecting its transmitted pulses, based on the profile values over time.
If you’re wanting to make your own Kalman filter, what would that be tracking? You could apply that to the sonar’s distance estimate, or its intensity measurements, but I’m not sure how helpful it would be to do either.