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).