RC Constant-Argument Driving-Point Admittances

This paper deals with a class of RC driving-point immittances characterized by nearly constant argument over an extended frequency range. These arguments may have an average value between the limits zero and \pi/2 radians. Networks having near constant argument are of importance in shaping the phase character of the forward gain in feedback systems. These networks have arguments that oscillate about a mean value and the nature of this oscillation is discussed. The poles of admittance are geometrically spaced along the negative-real frequency axis, and consequently the elements of the network' can be thought of as "spaced." The immittance functions and argument oscillations for the 22-1/2° , 45° and 67- 1/2° cases as a function of spacing are fully discussed. An application to a feedback amplifier design is given.