USING EXTRAPOLATION METHOD TO SEPARATE COHEREN T SOUND SOURCES

摘要

Patch near-field acoustic holography (NAH) can measure large source by a small holography surface to a great extent. However, accumulative error is increasing in the process of extrapolation and reconstruction of the data on holography surface. For reducing the accumulative error of patch NAH, a new method, directly extrapolating data on holography surface to reconstruct surface based on statistically optimal NAH (SONAH), is proposed and then applied to the sound field separation of coherent sound sources with double measurement surfaces based on SONAH and wave superposition algorithm in three steps. Firstly, setting two reconstruction surfaces near the two holography surfaces with SONAH, respectively; Secondly, more data on reconstruction surfaces can be obtained by less data on holography surfaces; Finally, separating the pressure of single source by wave superposition algorithm. Numerical simulations have been performed to compare the new separation method to the conventional one, and experiment has been done to verify the extrapolation method.