Harmonic interference removal using a fractional delay filter

Treats the harmonic interference removal where the frequency of the interference is a rational number and known in advance. In order to remove the interference from the corrupted signal without distortion we propose a structure, which uses a comb filter with a fractional delay. The polyphase structure with two output branches approximates a fractional delay. The proposed structure is convenient for the case when the delay is a ratio of high integers.