Fast simulation‐driven feature‐based design optimization of compact dual‐band microstrip branch‐line coupler. Issue 1 (24th July 2015)

• Record Type: Journal Article
• Authors: Koziel, Slawomir; Bekasiewicz, Adrian
• Is Part Of: International journal of RF and microwave computer-aided engineering. Volume 26:Issue 1(2016)
• Page Start: 13
• Page End: 20
• Publication Date: 2015-07-24
• Subjects: simulation‐driven design -- miniaturized microwave circuits -- microstrip couplers -- dual‐band couplers -- feature‐based optimization -- surrogate modeling; Microwave devices -- Computer-aided design -- Periodicals; Computer-aided engineering -- Periodicals; 621.3813
• DOI: 10.1002/mmce.20923
• Languages: English
• ISSNs: 1096-4290

Abstract

ABSTRACT: Design of miniaturized microwave components is a challenging task. On one hand, due to considerable electromagnetic (EM) cross‐couplings in highly compressed layouts full‐wave EM analysis is necessary for accurate evaluation of the structure performance. Conversely, high‐fidelity EM simulation is computationally expensive so that automated determination of the structure dimensions may be prohibitive when using conventional numerical optimization routines. In this article, computationally efficient simulation‐driven design of a miniaturized dual‐band microstrip branch‐line coupler is presented. The optimization methodology relies on suitably extracted features of a highly nonlinear response of the coupler structure under design. The design objectives are formulated in terms of the feature point locations, and the optimization is carried out iteratively with the linear model of the features utilized as a fast predictor. The entire process is embedded in the trust‐region framework as convergence safeguard. Owing to only slightly nonlinear dependence of the features on the geometry parameters of the circuit at hand, the optimized design satisfying prescribed performance requirements is obtained at the low computational cost of only 24 high‐fidelity EM simulations of the structure. Experimental validation of the fabricated coupler prototype is also provided. © 2015 Wiley Periodicals, Inc. Int J RF and Microwave CAE 26:13–20, 2016.