Research Group, GN ReSound A/South, Lautrupbjerg 7, 2750 Ballerup, Denmark.
J Acoust Soc Am. 2011 Jul;130(1):350-63. doi: 10.1121/1.3592240.
Feedback whistling is a severe problem with hearing aids. A typical acoustical feedback path represents a wave propagation path from the receiver to the microphone and includes many complicated effects among which some are invariant or nearly invariant for all users and in all acoustical environments given a specific type of hearing aids. Based on this observation, a feedback path model that consists of an invariant model and a variant model is proposed. A common-acoustical-pole and zero model-based approach and an iterative least-square search-based approach are used to extract the invariant model from a set of impulse responses of the feedback paths. A hybrid approach combining the two methods is also proposed. The general properties of the three methods are studied using artificial datasets, and the methods are cross-validated using the measured feedback paths. The results show that the proposed hybrid method gives the best overall performance, and the extracted invariant model is effective in modeling the feedback path.
反馈啸叫是助听器的一个严重问题。典型的声反馈路径表示从接收器到麦克风的波传播路径，其中包括许多复杂的效应，在给定特定类型的助听器的情况下，对于所有用户和所有声学环境，其中一些效应是不变的或几乎不变的。基于这一观察，提出了一种由不变模型和变体模型组成的反馈路径模型。基于公共声极点和零点模型的方法和基于迭代最小二乘搜索的方法用于从一组反馈路径的脉冲响应中提取不变模型。还提出了一种结合两种方法的混合方法。使用人工数据集研究了三种方法的一般特性，并使用测量的反馈路径对方法进行交叉验证。结果表明，所提出的混合方法具有最佳的整体性能，并且提取的不变模型在反馈路径建模方面非常有效。
