The Sequential Parameter Extraction for EM-based Design of Dielectric-resonator Bandpass Filter

In this paper, an efficient electromagnetic based design and optimization approach for dielectric-resonator bandpass filters is presented by exploiting sequential single terminal coupling matrix extraction and the space mapping techniques. This approach follows a sequential procedure in which the filter is designed by cascading resonators to a one-port sub-network successively. A single terminal sub-coupling matrix is built to extract newly added coupling elements and resonance frequencies by evaluating input impedance from the group delay feature points. Space mapping technique is exploited to efficiently approximate the best solution of geometric parameters in the electromagnetic model. Interpolation technique is also exploited during the optimization process to approximate the mapping using information from earlier optimization. An eight-pole dielectric-resonator bandpass filter is designed and optimized efficiently using Matlab and HFSS simulator to validate the proposed approach.