Fast redesign and geometry scaling of multiband antennas using inverse surrogate modeling techniques

Abstract

Redesign of antenna structures for various operating conditions or substrate parameters is a practically important problem in antenna engineering. At the same time, it is challenging because finding an optimum set of geometry parameters for a specified operating/material conditions requires going through an entire design optimization process. The problem is even more challenging for multiband antennas where 2 or more bands need to be independently controlled and the joint influence of some of antenna dimensions on several bands has to be taken into account. In this work, we propose a simple technique for rapid dimension scaling of multiband antennas, which uses inverse surrogate modeling techniques. The inverse surrogate model constructed using a set of reference designs optimized for several values of operating frequencies allows us to predict optimum dimensions of the antenna structure of interest corresponding to a required set of operating frequencies. The model is constructed at the level of coarse‐discretization electromagnetic simulations; therefore, it undergoes enhancement so as to be reliably used to redesign the antenna at the level of its high‐fidelity electromagnetic model. A correction procedure is further applied to accommodate the initial scaling errors. Our approach is demonstrated using a triple‐band uniplanar dipole antenna.

Expedited Feature-Based Quasi-Global Optimization of Multi-Band Antenna Input Characteristics With Jacobian Variability Tracking

“…The performance of the adopted approach is verified by analyzing the results obtained for multiple independent algorithm runs from random initial designs. Our benchmark set comprises two antenna structures: dual- [39] and triple-band [40] uniplanar dipoles shown in Fig. 4.…”

“…Exemplary reflection characteristics of (a) dual-[39]) and (b) triple-band antenna[40] at three different designs; characteristic points corresponding to the coordinates of the antenna resonances marked with (o); intended operating frequencies marked with vertical lines. Local (gradient-based) optimization routines starting from the designs (---) and (-) fail in the case of minimax formulation of the objective function as in(2).…”

“…Benchmark uniplanar dipole antenna structures used for verification of the proposed algorithm: (a) dual-[39] and (b) triple-band[40] antenna.…”

“…Operation of conventional routines for a triple-band antenna[40] (Algorithms 1 and 2), as well as their feature-based counterparts (Algorithms 3 and 4) for the representative algorithm runs starting from various initial designs: (1) reference TR algorithm with full FD Jacobian update, (2) expedited TR routine with Jacobian variability tracking, (3) basic version of the feature-based algorithm, and (4) expedited feature-based routine with Jacobian variability tracking.…”

Accelerated Re-Design of Antenna Structures Using Sensitivity-Based Inverse Surrogates

“…One of practical problems here is that as the number of operating conditions that are handled increase, so is the number of the reference designs needed to ensure uniqueness of the inverse model identification. For example, in [25], a total of 27 reference designs have been employed for addressing dimension scaling of triple-band antennas. In general, the number of such designs grows at a polynomial rate, more specifically, it is proportional to the second power of the number of the considered operating conditions.…”