Spherical microphone arrays and sound field decomposition using spherical harmonics is a well established technique for the analysis of sound fields, room acoustics or spatial audio recording applications. The Sound Field Analysis Toolbox (SOFiA) provides a MATLAB toolbox for the analysis of sound fields using data from spherical microphone arrays. It is freely available under the GNU GPL v3 license. For the evaluation of SOFiA, exemplary datasets from a VariSphear scanning array system are available under the Creative Commons license.
SOFiA can be downloaded here http://code.google.com/p/sofia-toolbox/
An overview of the SOFiA processing chain as well as a closer discussion of selected details can be found in the paper
B. Bernschütz, C. Pörschmann, S. Spors, and S. Weinzierl. SOFiA – Sound field analysis toolbox. In International Conference on Spatial Audio, Detmold, Germany, November 2011. [PDF]