Maynard J.

The ability to reconstruct a sound source using data measured in the nearfield of the source surface is clearly of great benefit in studying vibration and sound. Such reconstructions pose an interesting numerical problem because processing the measured data requires an inversion which is very often singular. The singular behavior arises from the loss of information from modes which decay rapidly away from the source and can be detected only in the nearfield of the source. By contrast, the process of constructing sound fields by propagating away from the source surface is relatively straightforward, and even provides a natural filter of the non-radiating modes. In this paper we present a new method of source reconstruction which uses propagation outward, with its natural filtering, together with a simple iteration scheme, to reconstruct a sound source. The source surface may or may not be a closed surface. Tests indicate that very accurate reconstructions are possible.