摘要
In this paper, we present a very efficient approath for the synthesis of twodimensional (2-D) re-cursive fan filters based on 1-D filter design. The investigation of the elliptical approximation theory mekesit possible to decompose a 1-D analogue filter into a series-parallel combination of all-pass sections. The 1-Ddigital filter obtained from this decomposition, while used as the prototype for 2-D filter synthesis, results ina grearly simplified realization architecture for fan filters. The final transfer function of the fan filter,which is reduced lo a combination of several lower-order all-pass sections, not only has fewer coefficients butalso enjoys optimal magnitude response. Some illustrative examples are given in this paper to show the effec-tiveness and simplicity of the proposed method.
In this paper, we present a very efficient approath for the synthesis of twodimensional (2-D) re-cursive fan filters based on 1-D filter design. The investigation of the elliptical approximation theory mekesit possible to decompose a 1-D analogue filter into a series-parallel combination of all-pass sections. The 1-Ddigital filter obtained from this decomposition, while used as the prototype for 2-D filter synthesis, results ina grearly simplified realization architecture for fan filters. The final transfer function of the fan filter,which is reduced lo a combination of several lower-order all-pass sections, not only has fewer coefficients butalso enjoys optimal magnitude response. Some illustrative examples are given in this paper to show the effec-tiveness and simplicity of the proposed method.