Limitations of the Virtual Rotating Array Method

Abstract

The virtual rotating array method is a widely used approach for the characterization of rotating sound sources. Because of its operation in the frequency domain it has some advantages compared to methods in the time domain. The most important are the extensive applicability of deconvolution algorithms and low computational costs. In the present study some limitations of the method are shown. A parametric study on several influencing factors is done. The goal is to find out how a ring array must be designed in order for the method to work for a particular test case. It can be shown that the incident sound waves must be spatially sampled with at least two microphones per wavelength for the interpolation to work. This is influenced by the angle of incidence of the sound, which depends on the radius of the source rotation and the ring array as well as their distance.