Generalized CIC-cosine decimation filter

This paper presents a new multistage CIC-cosine decimation filter. The cascade of expanded cosine prefilters is added to improve the stopband CIC characteristic. The passband characteristic of this filter is improved by adding the simple 2M-order compensation filter, where M is the decimation factor. Using the multirate identity the compensation filter is moved to a lower rate. The resulting structure is multiplierless and exhibits high aliasing attenuation and a low passband droop. For the special case where the decimation factor is in the form 2^k, where k is an integer, a speed and a low power structure is presented. The proposed method is compared with the selected existing methods.