Design of FIR fan filters using FIR hilbert transformer
Kiyoshi Nishikawa, Eiko Yamamoto · Electronics and Communications in Japan (Part III Fundamental Electronic Science) · 1992
Abstract A new, more direct method for synthesizing FIR fan filters and quadrantal fan filters using a FIR Hilbert transformer as the one‐dimensional (1‐D) prototype filter is described. Only the case 3 transfer function of the Hilbert transformer is available. When an equiripple design is used for the transformer, the ripple amplitudes in the passbands and stopbands of the resulting fan filter are nearly the same as the ripple amplitude of the transformer. The transfer function of the fan filter has only a few nonzero coefficients because the Hilbert transformer is required to be of even order. Illustrative examples of fan filter synthesis are presented.