Hat-type hearing aid system with flexible sound directivity pattern

Takayuki Inoue, Yusuke Ikeda, Yasuhiro Oikawa

Research output: Contribution to journalArticlepeer-review

1 Citation (Scopus)


For speech communication, it is useful to emphasise the sound coming from a target direction. A large-scale microphone array enables a flexible design of the directivity pattern. However, it is difficult to implement a large-sale microphone array onto an ear-type hearing aid system. In this paper, we propose a hat-type hearing aid system composed of 48 MEMS microphones that can increase the flexibility of the sound directivity pattern. We found that it is possible to reduce the number of microphones to be used by considering the hat effect, without affecting the system performance. By compensating the time delays and reducing the number of microphones based on impulse response measurements, the directivity range of the sound directivity pattern was improved by 5 dB. In addition, we conducted a qualitative evaluation that resulted in an intelligibility improvement when using our hearing aid system.

Original languageEnglish
Pages (from-to)22-29
Number of pages8
JournalAcoustical Science and Technology
Issue number1
Publication statusPublished - 2018


  • Delay-and-sum beamforming
  • FPGA
  • MEMS microphone array
  • Single-bit signal processing

ASJC Scopus subject areas

  • Acoustics and Ultrasonics


Dive into the research topics of 'Hat-type hearing aid system with flexible sound directivity pattern'. Together they form a unique fingerprint.

Cite this