Institute of Information Science, Academia Sinica

Under COVID-19, sound control in public spaces becomes more important to realize personal audio and silent workspace. Active noise control (ANC) is one of the solutions to realize a comfortable sound environment in public spaces. However, there are several challenges to implementing ANC in public spaces. One of the challenges is the spillover problem, the other is the size of the zone of quiet. Spillover means the increased sound pressure level outside the target area due to the directivity of the secondary loudspeaker. One of the solutions is to use a parametric speaker (PAL) as a secondary source. The second challenge is how to expand the zone of quiet (in short ZoQ). The size of ZoQ is strongly related to target noise frequency. One of the solutions is to use a special film speaker. This presentation focuses on the expanding ZoQ of semi-open booths with ANC using film speakers. Finally, I’d like to highlight the future challenges for improving ANC performance.

Yoshinobu Kajikawa received his B.E. and M.E. degrees, both in Electronic Engineering from Kansai University, Japan in 1991 and 1993, respectively, and D.E. degree in Communication Engineering from Osaka University in 1997. He joined Fujitsu Ltd. in 1993. In 1994, he joined Department of Electronic Engineering, Faculty of Engineering in Kansai University, Japan. He is currently a Professor of Department of Electrical, Electronic, and Information Engineering, Faculty of Engineering Science in Kansai University. His research interests are audio and acoustic signal processing including active noise control, directional sound system, spatial sound processing, and acoustic transducer design.
He received the 2012 Sato Prize Paper Award from the Acoustical Society of Japan (ASJ), the 2017 Sadaoki Furui Prize Paper Award from the Asia-Pacific Signal and Information Processing Association (APSIPA), and the 2020 Paper Award from the IEICE. He has published more than 250 international refereed journals and conferences, and has granted more than 40 Japanese, US, European, and Taiwan patents.
He is currently a Fellow of the IEICE and a Senior Member of IEEE. He served as the Editor-in-Chief of IEICE Trans. on Fundamentals of Electronics, Communications and Computer Sciences (2019-2021) and the chair of IEEE Signal Processing Society Kansai Chapter. He is currently serving as a BoG member (2022-2024) in APSIPA, the President (2023-2024) of IEICE Engineering Science Society (ESS), and a member of several IEEE SPS and CTSoC technical committees.
More information can be found in his website: 【Yoshinobu Kajikawa website】