Sound Source Localization - Door seal leaks: Beamforming + near-field focalization

This example tests the acoustic transparency of car door sealings. The set-up consists of a loudspeaker that generates acoustic excitations inside the car. The LMS Test.Lab High Definition Camera is used to measure acoustic leaks outside the care, both in the far field, using the beamforming technique, as well as in the near field, using near-field focalization. 
The left of figure 15 shows beamforming results measured at a distance of 60 cm. 2 leaks are found, one on the lower right part of the door, and one at the intersection of door and window. When zooming-in on this with near-field focalization, a more precise localization is possible, exactly on the door sealing, with an improved spatial resolution. Also 2 secondary sound sources are found, just above the main leak, and on the upper part of the door sealing. 












Figure 15: Door seal leaks from the far field and near field with dynamic range of 8dB 


More information on:

• Sound Source Localization technologies
• Acoustic beamforming technique and near-field focalization
• Acoutics holography technique
• Spherical beamforming technique for interior sound source localization