Optimal cascading design approach for digital dual-frequency notch filter

Digital dual-frequency notch filter is mainly used to remove or restrain the sinusoidal interferences with two frequencies contained in a digital signal. Firstly, the design method of the gain controlled filter with one notch frequency is presented in the paper. Secondly, using the special magnitude response control strategy and cascading two notch filters, the optimal design of the digital dual-frequency notch filter is realized. Finally, the practicability and effectiveness of the proposed design approach are verified by a series of simulation experiments.