고막이식형 마이크로폰을 위한 이식형 인공중이 적응 피드백 제거기 구현

• Published in: 멀티미디어학회논문지 Vol. 19; no. 2; pp. 189 - 199
• Main Authors: 김태윤(Tae Yun Kim), 김명남(Myoung Nam Kim), 조진호(Jin-Ho Cho)
• Format: Journal Article
• Language: Korean
• Published: 한국멀티미디어학회 2016
• Subjects: 전자/정보통신공학; F-IMEHD; Implantable Microphone; Adaptive Feedback Canceller
• ISSN: 1229-7771; 2384-0102
• DOI: 10.9717/kmms.2016.19.2.189

Many implantable hearing aids are being developed as alternatives to conventional hearing aids which has inconveniences for use and social stigma that make hearing-impaired people avoid to wear it. Particularly, the fully-implantable middle ear hearing devices (F-IMEHD) are being actively studied for mixed or sensorineural hearing impaired people. In development of F-IMEHD, the most difficult problem is improving the performance of implantable microphone. Recently, Cho et al. have studied the tympanic membrane installed microphone which has better sensitivity and is easier to operate on patient than the microphone implanted under the skin. But, it may cause howling problem due to the feedback signal via oval window and ossicle chain from the transducer on round window in the middle ear cavity, therefore, a feedback canceller is necessary. In this paper, we designed NLMS (normalized least mean square) adaptive feedback canceller for F-IMEHD with tympanic membrane installed microphone and a transducer implemented at round window, and computer simulation was performed to verify its operation. The designed adaptive feedback canceller has a delay filter, a 64 point FIR fixed filter and a 8-tap adaptive FIR filter. Computer simulation of the feedback path is modeled by using the data obtained through human cadaver experiment.