Active Acoustic Treatment (AAT) - A step toward a perfect sound absorber

P. G. Mehta, A. C. Zander, W. P. Patrick, Y. Zhang

Research output: Chapter in Book/Report/Conference proceedingConference contribution


Active Acoustic Treatment (AAT) is proposed as a method to absorb noise propagating in a duct with the objective of reducing the total noise power radiated from the duct exit. The effectiveness of AAT concept in attenuating both planar and higher-order acoustic duct modes is investigated experimentally in a rectangular duct. Decentralized feedback control is proposed as the control solution and is shown to perform satisfactorily. The performance of AAT is measured using 1) acoustic mode decomposition with microphone arrays located in the duct, upstream and downstream of the AAT sheet, and 2) a single microphone located external to the duct exit. Experimental results are included to demonstrate the attenuation of the total acoustic power propagating in the duct, and the reduction of the noise radiated from the duct.

Original languageEnglish (US)
Title of host publicationProceedings of the 1998 American Control Conference, ACC 1998
Number of pages5
StatePublished - 1998
Externally publishedYes
Event1998 American Control Conference, ACC 1998 - Philadelphia, PA, United States
Duration: Jun 24 1998Jun 26 1998

Publication series

NameProceedings of the American Control Conference
ISSN (Print)0743-1619


Other1998 American Control Conference, ACC 1998
Country/TerritoryUnited States
CityPhiladelphia, PA


  • Active noise control
  • Collocated control
  • Decentralized control
  • Duct noise control

ASJC Scopus subject areas

  • Electrical and Electronic Engineering


Dive into the research topics of 'Active Acoustic Treatment (AAT) - A step toward a perfect sound absorber'. Together they form a unique fingerprint.

Cite this