Design of Low-Pass Filters Using Discrete-Time Domain Techniques

In this paper, a new formulation of equal-length three-section open Stubs having two zeros located on the unit circle and one zero at z = -1 (0 = pi) in the Z-plane is presented. In Particular. new filter configurations consisting of equal-length two-section open stubs, cascade lines, Open Stubs, and three-section Open Stubs are employed to emulate the discrete-time filters. To examine the validity of our formulation. we realized two discrete-time Chebyshev type II low-pass filters in the form of microstrip lines. The frequency responses of these two filters are measured to Validate this new formulation.