ACOUSTIC BESSEL BULLETS

✍ Scribed by P.R. Stepanishen

• Book ID: 102606204
• Publisher: Elsevier Science
• Year: 1999
• Tongue: English
• Weight: 370 KB
• Volume: 222
• Category: Article
• ISSN: 0022-460X
• DOI: 10.1006/jsvi.1998.2040

✦ Synopsis

Acoustic Bessel Bullets (BB) are de®ned to be a new class of band-limited Transient Bessel Beams or localized waves which maintain their shape and amplitude as they propagate in space. The space±time properties of acoustic BB ®elds generated by planar spatial apertures excited with gated sinusoidal excitations are investigated using a recently developed generalized impulse response approach. Analytical results are presented for the general characteristics of acoustic BB ®elds generated by in®nite and ®nite planar apertures as a function of center excitation frequency and bandwidth. Numerical results are then presented to illustrate the space±time properties of the on-axis ®eld for acoustic BB ®elds relative to those of a conventional piston source. The near to far®eld transition distance for acoustic BB ®elds is investigated and compared to the Rayleigh distance for a piston source. Important edge wave eects and anomalous spatial decay rates are observed and discussed.