Digital Filter design plays a vital role in signal processing and communication applications. This paper proposes a hearing loss system model with Variable Bandwidth FIR Filter (VBF) and adaptive algorithms for the application to listening. The tunable band filter is designed to provide an appropriate sound level. This filter has several sub-filters each of which is designed with set of selected bandwidths. The sub-bands obtained are adjusted with proper magnitude by trial and error method. Algorithms such as Least Mean Square (LMS), Normalized Least Mean Square (NLMS) and Recursive Least Squares (RLS) are incorporated to improve the quality of the signal. The filter thus designed is examined by taking a number of audio signals. The tests on various hearing loss cases with different type of input signal suggest that this method is capable of reproducing a signal which sounds exactly the same as the original signal. The multiple bandwidth filters is analyzed with mild, moderate, profound and severe hearing loss patterns and the results are reported. The matching error is calculated between ideal response and actual response. The result show that the designed filter provides acceptable minimum matching error and it lies in the range 0 to 2.5dB.This filter design is implemented in TMS320C6711 processor and is tested for sinusoidal input signal.

中文翻译：

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自适应算法的多带宽FIR滤波器设计

数字滤波器设计在信号处理和通信应用中起着至关重要的作用。本文提出了一种具有可变带宽FIR滤波器（VBF）和自适应算法的听力损失系统模型，以用于听力应用。可调带通滤波器旨在提供适当的声级。该滤波器具有几个子滤波器，每个子滤波器都设计有一组选定的带宽。通过反复试验法将得到的子带调整为适当的大小。诸如最小均方（LMS），归一化最小均方（NLMS）和递归最小方（RLS）之类的算法已被纳入以提高信号质量。通过获取许多音频信号来检查如此设计的滤波器。对具有不同类型输入信号的各种听力损失病例的测试表明，该方法能够再现听起来与原始信号完全相同的信号。使用轻度，中度，深度和严重的听力损失模式分析多带宽滤波器，并报告结果。匹配误差是在理想响应和实际响应之间计算的。结果表明，所设计的滤波器提供了可接受的最小匹配误差，范围为0至2.5dB。该滤波器设计在TMS320C6711处理器中实现，并经过正弦输入信号测试。匹配误差是在理想响应和实际响应之间计算的。结果表明，所设计的滤波器提供了可接受的最小匹配误差，范围为0至2.5dB。该滤波器设计在TMS320C6711处理器中实现，并经过正弦输入信号测试。匹配误差是在理想响应和实际响应之间计算的。结果表明，所设计的滤波器提供了可接受的最小匹配误差，范围为0至2.5dB。该滤波器设计在TMS320C6711处理器中实现，并经过正弦输入信号测试。