An adaptive noise canceller for hearing aids using two nearby microphones

Area of Science:

• Audiology
• Signal Processing
• Acoustics

Background:

• Hearing aids often struggle to isolate speech in noisy environments.
• Adaptive noise cancellation aims to improve speech clarity for hearing aid users.
• Two-stage adaptive filtering offers a potential solution for enhanced noise reduction.

Purpose of the Study:

• To evaluate an adaptive noise cancellation (ANC) scheme using two-stage adaptive filtering.
• To assess the effectiveness of the ANC system in a behind-the-ear (BTE) hearing aid configuration.
• To measure improvements in speech intelligibility for hearing-impaired individuals in background noise.

Main Methods:

• Implemented a two-stage adaptive filtering ANC scheme.
• Utilized two identical directional microphones in an endfire configuration within a BTE hearing aid.
• Conducted speech intelligibility tests with normal-hearing subjects and hearing aid users in a realistic noise environment.

Main Results:

• Achieved a significant improvement in the speech reception threshold (SRT).
• The average improvement in SRT was greater than 5 dB in background noise.
• Demonstrated enhanced speech reception capabilities of the tested ANC system.

Conclusions:

• The adaptive noise cancellation scheme shows promise for improving hearing aid performance.
• The two-stage adaptive filtering approach effectively reduces background noise.
• This technology can lead to better speech understanding for individuals with moderate hearing loss.