Design of multiplierless compensator for multistage decimation filter.

This paper investigates how to correct the pass-band droop in a CIC (cascaded-integrator-comb) filter with multiple stages. This filter has been recently proposed in the literature. However, the method to correct the pass-band characteristic is not considered. Instead, the technique utilized for sharpening CIC is applied. The structure requires a minimum number of adders per output sample (APOS) for a given minimum worst-case folding band attenuation and pass-band edge. We consider the designs for narrow-band and wide-band cases. The magnitude characteristic in the wide-band case is chosen as a product of two sinusoidal, while one single sinusoidal function is utilized in the narrow-band case. The design parameters are the amplitudes of the sinusoidal functions in both cases. We propose applying particle swarm optimization (PSO) to find optimal values of design parameters. Next, the optimal parameters are presented in a power-of-two form to get a multiplier-less design. The proposed technique is illustrated with examples. [ABSTRACT FROM AUTHOR]