Design and synthesis of filter bank structures based on low order constrained least square and minimum phase methods for audiogram matching in digital hearing aids

AbstractFrequency decomposer or filter bank plays acritical role in the design of digital hearing aid systems.This paper proposes filter bank structures suitable for the design of optimal hearing aid systems.The performance indices such as complexity, power dissipation, area utilization, delay, matching error of the filter banks are very competitive when compared to the designs in literature.Constrained least square finite impulse response filter with smooth transition band characteristics is used in the first method.The second method is based on Minimum phase filters with reduced number of coefficients which exhibit the smallest passband group delay in the family of filters with the same magnitude response characteristics.Hardware complexity is reduced very much since there is significant reduction in multiplications per sample in both the methods.Full cycle responses of individual filters are considered for calculation of overall response of the filter bank.Coefficient decimation method is used in the reconfigurable structure to enable the filter banks to adapt variation in audiogram pattern during the course of time.Synthesis results by Cadence Encounter(R.) R.T.L. Compiler software also justify the theoretical claims
Source: Health and Technology - Category: Information Technology Source Type: research