Study on the Mechanism of Duct Active Sound Attenuation and Review on the Related Elements Development

The authors summarize the sound wave interference attenuation principle and impedance control attenuation mechanism of duct active noise attenuation technology, and the development of microphone, loudspeaker and controller elements. The research achievements and progresses, especially the applications of smart materials in this area, are particularly discussed. At last, the developing trends for further study on these subjects are forecast