Comparison of classical CIC and a new class of stopband-improved CIC filters formed by cascading non-identical comb sections

In this paper we propose a new class of selective CIC filters in recursive and nonrecursive form. The filters use a modification of CIC concept, which is achieved by applying a set of non-identical comb sections in cascade. We illustrate examples of the proposed filter function and calculate integer coefficients of filter impulse response. Detailed comparison between the proposed selective filter class and classical CIC filters is given. The results show that the stopband selectivity can be improved significantly in comparison with classical CIC filters with the same filter complexity.