Radiated noise sources location based on MVDR near-field focused beamforming

Noise sources image can be used to determine the spatial distribution of the major noise sources. Thereby we can adopt damping and noise-reducing measures pertinently. In the near-field, compared to the conventional beamforming (CBF), focused beamforming should compensates the time-delay difference and the magnitude attenuation by spherical wave rules according to the different curvature radiuses between the source and array elements, and the time-delay difference value is the 2-dimensional function of both bearing and range. In this paper, the MVDR near-field focused beamforming algorithm and wideband MVDR near-field focused beamforming algorithm are presented. The location performance of both single frequency line spectrum noise and wideband noise signal is improved markedly. Because of making use of various spectrum band signal energy fully, we can scale the noise sources spatial distribution more roundly.