Design of microphone phased arrays for acoustic beamforming

  • Filipe Ramos do AmaralEmail author
  • Juan Carlos Serrano Rico
  • Marcello Augusto Faraco de Medeiros
Technical Paper


The design of a microphone array affects the performance of beamforming algorithms in the localization and evaluation of acoustic noise sources. This paper addresses a circular phased array design for near-field aeroacoustic measurements in a closed-test-section wind tunnel. Microphones were distributed in rings and occupied an equal aperture area—each ring could have a different number of microphones. The array performance was evaluated through the dynamic range and array resolution given by the beamwidth. The array designed for the exploration of the novel approach had 112 microphones and 950-mm aperture. In comparison with classical designs, also optimized for the same number of microphones and aperture, the approach provided the best array resolution and a high dynamic range level almost uniform over the frequency range of interest (800 to 20,000 Hz). Microphone shading was also assessed for improving the array performance, and the employment of only the outermost microphones (the innermost ones were shaded) reduced approximately 40% the array beamwidth.


Aeroacoustics Microphone phased array design Acoustic beamforming technique 



F.R.A. received funding from Coordination for the Improvement of Higher Education Personnel (CAPES/Brazil), Grant #DS00011/07-0. J.C.S.R. received support from National Council for Scientific and Technological Development (CNPq/Brazil), Grant #140211/2014-4. M.A.F.M. received support from CNPq/Brazil, Grant #304859/2016-8. The authors also acknowledge the Sao Paulo Research Foundation (FAPESP/Brazil) and EMBRAER S.A./Brazil, Grant #2006/52568-7, Funding Authority for Studies and Projects (FINEP/Brazil), Grant #01.09.0334.04, for their financial support, Mr. Christian Salaro Bresci and Mr. Matheus Maia Beraldo, for their technical support with the loudspeaker experiment and Mrs. Angela Giampedro for her support with the scientific writing.


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Copyright information

© The Brazilian Society of Mechanical Sciences and Engineering 2018

Authors and Affiliations

  1. 1.Department of Aeronautical EngineeringUniversity of Sao PauloSao CarlosBrazil
  2. 2.Programa Ingeniería Mecánica, Universidad de PamplonaPamplonaColombia

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