21 Band 1/3-Octave Filter bank for digital hearing aids

ANSI S1.11 1/3 Octave Filter bank is popular in acoustic applications due to well matching the frequency characteristics of human ears. However high computation complexity limits its usage. This paper deals with the digital hearing aids which consumes less power and cover the human voiced speech frequency correctly. The technique called the complexity-effective multirate FIR filter bank algorithm with a systematic coefficient design flow is proposed to reduce the order of the filter. In existing method 18 bands were used. It cover the frequency range from 140Hz to 8979Hz. It didn´t cover the human voice frequency fully. Because the voiced speech of a typical adult male starts from 80Hz to 145Hz. Here 21 bands are used with Finite Impulse Response (FIR) filters. This filter has been simulated in Synopsys. The proposed method consumes less power which is 30%-79% less of other methods and cover the human voiced speech frequency.