Passive imaging of scatterers based on cross-correlations of ambient noise

Recent studies have demonstrated that Green's function between two points can be retrieved from crosscorrelation functions of ambient noise recorded at these two points.Green's function retrieval is applied to road traffic noise and beach surfing noise.Scattered arrival waves are retrieved from cross-correlations of noise recorded at pairs of microphones.Through the least squares approach and Kirchhoff migration algorithm,the feasibUity of passive imaging of scatterers with ambient noise around kilohertz is experimentally demonstrated for the first time.The accuracy of scatterer passive imaging is confirmed by comparison with ground truth measurements.The experimental results indicate that Green's function retrieval using cross-correlations of ambient noise can be a new way for the design of indoor passive acoustic monitoring system,and provides a good prospect of imaging silent target in water by using ocean ambient noise.