An accurate MATLAB-based CAD algorithm for analyzing microstrip-based stepped-impedance resonator (SIR) low-pass filters is reported. The algorithm uses a circuit theory approach to implement speedy computations, compared to computations done using electromagnetic theory.
The accuracy of the proposed algorithm is verified for two widely different practical examples, against results obtained using Ansoft’s simulation tool. The agreement between the two sets of data is seen to be excellent for most cases, and practically acceptable in the worst-case.