Time domain holography: Forward projection of simulated and measured sound pressure fields

In this article, the fundamental principles of forward projecting time domain acoustic pressure fields are summarized. Four different numerical approaches are presented and compared both with simulated and measured signals. The approaches differ in their definition domain: Frequency/time and space/wave vector domains. The simulated source is a planar baffled piston excited with a Gaussian pulsed velocity. The pressure radiated by two different real sources has been measured: The first source is made up of two baffled loudspeakers (a Gaussian white noise can be radiated by a third loudspeaker). The second one is a baffled aluminum plate excited by a short impact at its center. The influence of parameters such as the sound source radius, the array size, the number of microphones and the propagation distance is studied. Finally, results concerning the optimization of the sampling of the sound field are presented.