Figure 1: Alumina substrate based microstrip filter (3D model)
Figure 2: Frequency response
Description
Microstrip filter based on open/shorted stubs.
Design Method
Design method is based on solving of electromagnetic scattering problem of double-discontinuity junctions of strip/microstrip lines. Semi-numerical solution is derived for several types of open and shorted stubs. The obtained formulation is represented as fortran code and compiled into design tool. The design tool consists of four program modules; filter synthesizer, frequency response simulator, and optimizer and HFSS/AutoCAD converter. Accuracy of software is within manufacturing and tuning margins.
