Acoustic Technology, Department of Electrical Engineering, Technical University of Denmark, Building 352, DK-2800 Kongens Lyngby, Denmark.
J Acoust Soc Am. 2011 Jun;129(6):3461-4. doi: 10.1121/1.3575603.
Spherical near field acoustic holography (spherical NAH) is a technique that makes it possible to reconstruct the sound field inside and just outside a spherical surface on which the sound pressure is measured with an array of microphones. This is potentially very useful for source identification. The sphere can be acoustically transparent or it can be rigid. A rigid sphere is somewhat more practical than an open sphere. However, spherical NAH based on a rigid sphere is only valid if it can be assumed that the sphere has a negligible influence on the incident sound field, and this is not necessarily a good assumption when the sphere is very close to a radiating surface. This Letter examines the matter through simulations and experiments.
球近场声全息术（spherical NAH）是一种能够重建球面上测量的声压的声场内及外部声场的技术，该球面可以是声学透明的，也可以是刚性的。刚性球比开球更实用。然而，基于刚性球的球近场声全息术只有在假设球对入射声场的影响可以忽略不计的情况下才有效，而当球非常接近辐射面时，这并不一定是一个好的假设。本研究通过模拟和实验研究了这一问题。
