Trigonometrical approach to design a simple wideband comb compensator

This paper presents a trigonometrical approach to design a simple second order wideband compensator of a comb decimation filter. The method is based on the similarity of the inverse passband comb characteristic and the squared sine function. The design parameter B, which is the amplitude of the squared sine function, depends only on the number K of the cascaded comb filters. Considering that the parameter B can be expressed in terms of only addition and shift operations, we may obtain a multiplierless filter. The proposed filter performs wideband compensation efficiently using a maximum of four additions/subtractions, and for a given K, can be applied to any value of the decimation factor M.