8-BAND HETEROGENEOUS BANK OF FIR FILTERS WITH HIGH COMPUTATIONAL EFFICIENCY FOR HEARING AIDS

Abstract

This article discusses recursive filters with finite impulse response and filter banks. The filter bank is an array of bandpass filters. The analysis filter block divides the input signal into several components, with each of the sub-filters carrying one frequency sub-band of the original signal. On the contrary, the synthesis filter block combines the output data of the sub-bands to restore the original input signal. In most applications, certain frequencies are more important than others. Filter blocks can isolate various frequency components in the signal. This way we can put more effort into processing more important components and less effort into processing less important components. Subband filters can be combined with step-down or step-up sampling to form a bank of multi-speed filters. Filter banks are widely used for speech recognition and speech quality improvement. Currently, filter banks have expanded their application to video and image processing. In addition, filter blocks are very useful in communication systems, including digital receivers and transmitters, pre-coding of filter blocks for channel alignment, discrete multi-tone modulation and blind channel alignment. The use of these filters for hearing aids is considered. An 8-band heterogeneous bank of recursive filters with finite impulse response (FIR) with high computational efficiency for hearing aids has been developed. The computational complexity (BC) of a recursive filter with a finite impulse response (RCIHF) is also compared with the computational complexity of non-recursive filters with a finite impulse response (NCIHF).