一种用于听力矫正系统中非均匀余弦调制滤波器组的设计

A Design of Non-Uniform Cosine Modulated Filter Banks for Hearing Correction System

为改善多通道滤波器组分解导致语音质量下降的问题,本文提出了一种应用于听力矫正系统的非均匀余弦调制滤波器组的设计算法。该算法设计步骤简单且性能优越,它根据听损患者听力图的变化趋势,对变化平缓的频率范围对应的均分余弦调制滤波器组的通道进行合并,从而使滤波器的分解更加符合听力矫正系统的验配需要。波形实验结果显示,信号经非均匀余弦调制滤波器组后,时域波形与语谱图相较于原始输入信号无明显失真,差异较小。语音质量实验结果显示,本文提出的非均匀滤波器组的主观语音质量评估值较高,语音信号通过滤波器组后失真程度小,滤波器组性能优于传统的设计方法。

Efficient design of non-uniform cosine modulated filter banks for hearing correction system is proposed to promote the performance of traditional multi-channel filter banks which lead to speech quality degradation.The advantages of the proposed structure are simple,less complexity and excellent performance.According to the trend of audiogram of hearing impaired persons,the adjacent channels which have low or gradual slopes of a uniform filter banks are merged,which satisfies the decomposition filters requirements of hearing aids fitting better.Simulation results show that the signal processed by the proposed filterbanks is similar to the original signal in time-domain waveform and spectrogram and has no significant distortion or difference.Results of speech quality show the proposed method has the better perceptual evaluation of speech quality and the less distortion than the traditional design.