Feedforward controller has been widely used for active noise control systems. IIR or FIR adaptive filter is used for Filtered-X LMS algorithm which can be categorized as feedfoward control. FIR filter is preferred to IIR filter due to IIR filter's instability and nonlinearity problems. However, FIR filter needs a large number of weights to control sounds in a lightly damped system.
In this study, a new adaptive filter, which uses linear combination of IIR filter bases, is proposed. IIR based adaptive filter become a Prony model when impulse responses of IIR filters are in forms of exponential sine and cosine. Using this adaptive filter, we can control sound pressure in a lightly damped field with a small number of IIR filter weights compared to that of FIR type weight, we can selectively choose the control frequency range by appropriately assuming frequencies of Prony model used as IIR filter bases.
Experiments and simulation results demonstrate the feasibility of the proposed method.
