A comparison of iterative sparse equivalent source methods for near-field acoustical holography.

During the past decade, several publications have described the use of compressive sensing principles to extend the frequency range supported by a given irregular microphone array for near-field acoustic holography. The applied numerical source model has typically been of the type used for the equivalent source method, i.e., a mesh of point sources, and a one-norm regularized inverse problem has been solved using a very stable, but slow interior-point optimization algorithm. A few publications have investigated the use of simpler and faster iterative algorithms. The present paper gives a brief description of five such iterative algorithms, and it compares their performances with that of the interior-point algorithm based on a set of simulated measurements. A particular focus is on the suitability for industrial applications. Finally, an optimal choice of methodology is discussed based on the presented limited set of simulated tests.