ABSTRACT
The SFT-NAH (Spatial Fourier Transform Nearfield Acoustic Holography; Chen & Bi 2013) is a technology of sound field transform based on fluctuation acoustic. It uses the measurement results of a variable acoustic in the sound field of a region near the sound source, for example the distribution of complex sound pressure, to reconstruct an acoustic hologram of other regions including the sound source surface and the spatial distribution of a variety of variable acoustical in the near field and the far field. The basic flowchart of the PNAH
1 INTRODUCTION
Since the use of the acoustic holography technology to measure submarine radiated noise, which was proposed first by Williams et al. (1985, 1999) from the Naval Research Laboratory, military powers have carried on acoustic holography technology research and military applications. However, the countries that have truly made this technology practical include only the USA and France, and a handful of countries.
