Arbitrary filter design by using nonuniform transmission lines

We develop new formulations of reflection and transmission coefficients of nonuniform transmission lines having unequal reference impedances. By using the ABCD transmission matrix of a transmission line, we express the reflec tion and transmission coefficients of a nonuniform line as polynominal rati os in Z transforms. These formulations, in conjunction with digital signal processing (DSP) techniques and a reconstruction method, lead to the realiz ation of nonuniform lines which satisfy prescribed scattering characteristi cs in frequency domain. Some examples are presented to illustrate the valid ity of this technique.