Design formulas for stepped impedance distributed and digital wave maximally flat and Chebyshev low-pass prototype filters

Design formulas are obtained for the basic stepped impedance distributed low-pass prototype filter which exhibits a maximally flat or equiripple insertion loss response characteristic. Explicit formulas are given for the coefficients of a truncated power series in the bandwidth scaling factor for the characteristic impedances. For the low-sensitivity digital wave filter based upon this prototype, the multiplier values are given. Computer results on the analysis of the prototype filter using the new design equations are cited, showing the vast improvement over the narrow band, lumped element, explicit design formulas.