Scattering properties and echo modeling of diver´s lung

Underwater diver is a critical object to research in underwater target detection. The key scattering factors of a diver include human body, dry diving suit, scuba bottle, open-circuit bubble cloud, etc. Of all these factors, human lung is an important scatterer. In this paper, ignoring the influences of acoustic attenuation on tissues and considering shear wave in human lung tissue, we proposed a double-layered elastic sphere model as diver´s lung. Based on the proposed model, the scattering field of lung is presented and formula of its form function is obtained. From the form function, the echo wave form is predicted. Simulation results show that if incident by a single CW pulse, lung will scatter a series of pulses.