|
KMID : 0372919980190060623
|
|
Journal of Biomedical Engineering Research
1998 Volume.19 No. 6 p.623 ~ p.629
|
|
|
Amplification and Howling Suppression of Telephonic Speech for the Hearing-Impaired Person
|
|
Lee Sang-Min
|
|
|
Abstract
|
|
|
|
To provide sufficient sound to the hearing-impaired person(HIP) who have many difficulty in communication with others using general telephone, big amplification is needed. But big amplification can occur howling as a side effect. In this study we developed the new technique of big amplification without howling, manufactured and estimated the new hearing aid telephone. Telephone speech is divided to three frequency band, amplified respectively and fitted to HIP’s hearing ability. The telephone speech frequency is monitored by counter in time domain. The counter transfers the sinusoidal sound to rectangular wave using comparator and counts the number of rectangular wave in a certain time period, that is frequency, to monitor the howling. Telephone have microphone and speaker, which are fitted in a rigid structure and frequency band of telephone sound is limited, so howling occurs in the limited frequency band. If the counter notices that howling conditions happen, microprocessor decreases quickly the gain of the related frequency band. The result of test of our new hearing aid telephone showed that we can amplifiy the sound as much as 40dB, which is meaningful level to many HIP, and make HIP increase their perception ability from 20% to 60.8% in 1 syllable test and from 28.9% to 78% in 2 syllable test.
|
|
|
KEYWORD
|
|
|
Hearing impairment, Hearing aid telephone, Howling suppression
|
|
|
FullTexts / Linksout information
|
|
|
|
|
|
Listed journal information
|
|
|
|
|