Innovative design of CIC FIR filter functions

An innovative design of CIC (Cascaded-Integrator-Comb) FIR (finite impulse response) filter functions based on spreading the delays in the CIC filter comb stages is described. The method is given in a closed-form which provides the impulse response coefficients analytically. The benefit of the new filter class is shown through a few example filter functions and their comparisons with existing classical CIC structures and some improvements given in the recent papers. The novel cascaded-filter architecture shows valuable benefits: increased minimum attenuation in stopband, smaller impulse response coefficient values, and decreased passband droop.