Drop parameter estimation from underwater noise produced by raindrop impact

Abstract

A study is presented of the acoustic signals produced by raindrops impacting on the surface of water contained in a sensor assembly. The impact generates low frequency damped pressure waves in water. The low frequency spectrum of this signal is seen to be fairly consistent and is used for measuring the kinetic energy of the raindrops from which the drop-size distribution and the rain intensity are estimated. The proposed method is computationally efficient and can be implemented with simple DSP hardware.