Digital Multiple Notch Filter Design Based on Genetic Algorithm

Digital multiple notch filters are applied to remove or suppress several narrow-band interference components simultaneously in a digital signal while preserve the other frequency components unchanged. A novel design method of an infinite impulse response (IIR) multiple notch filter is presented in this paper. It is based on genetic algorithm (GA) which is one of the very effective tools of optimization. Firstly, the rational system function of the notch filter is constructed and the optimized objects are determined. Secondly, the pole angles related notch bandwidths are optimized by genetic algorithm. Finally, the effectiveness and practicability are verified by some experimental results. The proposed design method obtains better magnitude response than the traditional cascading design method. It has good versatility and can be applied in speech processing, communication, biomedical engineering and other technical fields.