Abstract :
Much of the tedium of filter design has been eliminated by previously published tabulations of element values, pole locations, polynomial coefficients, and similar data for several conventional types of filters. The transient responses of some of the same types of filters have been computed and plotted in this paper. The curves presented are the normalized impulse and step responses of the first ten orders of the low-pass and high-pass Butterworth (maximally-flat) and Tchebycheff (equal-ripple) types, with band-pass ripple of 0.5, 1, and 2 db for the latter, and the low-pass Bessel (maximally-flat time delay) type. The method of calculation of the responses is described in detail, and some interesting properties of the pole loci are explained. The calculations were performed with a digital computer.
