Space Mapping Design Framework Exploiting Tuning Elements

Inspired by the ideas of ¿simulator-based¿ tuning, implicit space mapping, and surrogate optimization, we propose an implementable microwave design framework. In this framework, we alter an electromagnetic (EM) model by embedding suitable tuning elements. The resulting tuning model is aligned with the original unaltered EM model. We then designate the aligned tuning model as surrogate for design optimization purposes. We illustrate our tuning space mapping framework using a simple microstrip line example. Several microwave examples, including a low-temperature co-fired ceramic filter demonstrate the framework's implementation and robustness.

I. Introduction

Electromagnetic (EM) simulation is accurate, but CPU intensive; hence, using a full-wave EM simulator to optimize a complex structure may be prohibitive. An approach is to use decomposition, i.e., to break down an EM-based model and combine the components within a circuit simulator in the hope of reducing CPU demand. Co-simulation or co-optimization of EM/circuits [1]–[7] is a common industry solution to blend EM-simulated components into circuit models. These methods embed parameterized EM or interpolated EM components in a circuit simulator to form a surrogate for optimization. Swanson et al. [8], [9] and Rautio [10] propose a “simulator-based” tuning method in which circuit-theory-based tunable elements are embedded in an EM simulator through internal ports created in the EM model. The resulting surrogate can be optimized.