Noise reduction for hearing aids using digital signal processing

使用数字信号处理降低助听器的噪音

基本信息

批准号：
05452333
负责人：
SONE Toshio
金额：
$ 3.52万
依托单位：
TOHOKU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (B)
财政年份：
1993
资助国家：
日本
起止时间：
1993 至 1994
项目状态：
已结题

项目摘要

1. Algorithm for noise reduction An algorithm for reducing stationary/nonstationary environmental noise has been developed and has been verified via computer simulation. Moreover, total noise reduction system has been constructed using signal processing system. For ebvironmental noise reduction, an adaptive beamforming technique was combined with conventional fixed beamformer to obtain robust attenuation for not only stationary noise but also nonstationary noise. On the other hand, for reducing howling, adaptive feedback canceler was introduced.2. Evaluation The system developed has been applied to real environmental noise and was evaluated in terms of the amount of noise reduction and other issues. The results can be summarized as follows : As for the environmental noise, directional noise with large power was reduced by more than 20 dB,while nondirectional noise such as reverberation is also reduced by 10 dB.As for the howling, howling margin increased by 20 dB.3. Improvement in Speech Intelligibility Noise reduction system has been applied to the speech corrupted by noise, and the listening test was conducted. The results can be summarized as follows : As for the environmental noise reduction, the speech intelligibility was improved from 50 % to 70 % by introducing the proposed system. As for the howling cancellation, periodic signals such as voiced speech is corrupted by the conventional adaptive feedback canceler. However, use of frequency compressor together with adaptive feedback canceler as proposed in our system yields little corruption and no effect on speech intelligibility.

1。降噪算法，已经开发了用于减少固定/非机构环境噪声的算法，并已通过计算机模拟进行了验证。此外，使用信号处理系统构建了总降噪系统。对于降低EBVINCLENTAL噪声，将一种自适应波束形成技术与常规的固定光束形成器结合使用，以获得不仅固定噪声，而且是非平稳噪声的强大衰减。另一方面，为了减少how叫，自适应反馈取消器。2。评估该系统已应用于真实的环境噪声，并根据降低降噪和其他问题进行了评估。结果可以总结如下：至于环境噪声，具有大功率的方向性噪声减少了20 dB，而非方向噪声（例如混响）也减少了10 dB。语音可理解性降低降噪系统的改善已应用于噪音破坏的语音，并进行了听力测试。结果可以总结如下：至于降低环境噪声，通过引入所提出的系统，语音清晰度从50％提高到了70％。至于how叫取消，传统的自适应反馈取消器损坏了诸如声音语音之类的定期信号。但是，使用频率压缩机以及我们系统中提出的自适应反馈取消器的使用几乎没有腐败，对语音清晰度没有影响。