Microwave Circuit Optimization Exploiting Tuning Space Mapping

Abstract

This thesis contributes to the development of tuning space mapping (TSM) for computer-aided design and optimization of microwave circuits. Tuning space mapping applies the traditional engineering tuning idea into the realm of space mapping. It takes advantage of both the efficiency of space mapping and the expertise required for tuning of engineering devices. We present the state of the art in tuning space mapping and selected applications, and discuss how it relates to regular space mapping. A TSM algorithm is illustrated and implemented. Tuning space mapping shifts the burden of optimization from expensive electromagnetic (EM) models to cheap and fast tuning models. Meanwhile, design accuracy is achieved by keeping the EM simulation result in an S-parameter file in the circuit simulator, while performing optimization only on certain circuit theory-based components that are introduced into the tuning model. One important step in this tuning approach is to translate the tuning parameters to adjustments in the design parameters. Up to now, this was implemented by experience. Scarcely any systematic algorithm was suggested. In this thesis, we introduce a systematic "calibration" process which aims at calibrating the EM dimensions by the optimizable tuning parameters. Several calibration methods can accomplish this translation process. They are demonstrated here by applications.