论文期刊

Shape recognition of acoustic scatters by using the singularity expansion method




作者: Pei Cao, Jiu Hui Wu
发表/完成日期: 2017-03-01
期刊名称: Journal of Applied Physics
期卷: Vol.121, No.10
相关文章: Shape recognition of acoustic scatters by using the singularity expansion method.pdf   
论文简介
Acoustic target recognition for two-dimensional (2D) acoustic scatterers is investigated using the
singularity expansion method (SEM). Based on the Watson transformation series of the scattering
field, the SEM poles can be calculated and their physical interpretation given, along with the exact
normal mode for any acoustic scattering problem. Typical oscillatory phenomena appear as a series
of damped sinusoidal signals in the time domain and as a standing-wave distribution in the space.
These external oscillation modes are associated with the SEM poles. We note that the positions of
these poles in the complex frequency plane are uniquely determined by the shape and flexible characteristics
of the target regardless of the waveforms and positions of the incident signals. We then
infer that SEM poles can be used as the characteristic parameters for target shape recognition. The
relationship between the positions of SEM poles and the geometrical characters of 2D scatterers
has been established not only for cylinders but also for other general 2D scatterers. The new
method and the related calculation results provide an effective way to perform shape recognition
using an acoustic scattering field, with potential applications in non-destructive testing and acoustic
imaging.