{"title":"Unbalanced-Fed TCDA Performance Improvement Using a Scan Impedance Model","authors":"Eric D. Robinson;Carey M. Rappaport","doi":"10.1109/OJAP.2024.3413012","DOIUrl":null,"url":null,"abstract":"Unbalanced-fed Tightly-Coupled Dipole Arrays (TCDAs) allow for the realization of ultrawideband, wide-scanning phased arrays without the need for baluns, which may increase size, weight, and cost. However, unbalanced-fed TCDAs often have additional radiating modes and common-mode resonances which may degrade performance. In this paper, a scan impedance model is presented which describes performance in terms of a combination of even and odd monopole and dipole radiating modes. An intermodal coupling term is included to account for performance when scanning in the E-plane. Each mode is calculated individually in a full-wave solver and the model is then validated by comparing the proposed combination to a full simulation of the unbalanced-fed TCDA. A coaxial extension technique is then introduced to increase the impedance of the monopole-like radiating even mode, allowing the unbalanced-fed array to match the performance of the balanced-fed version without shorting posts or significant redesign of the elements or lattice.","PeriodicalId":34267,"journal":{"name":"IEEE Open Journal of Antennas and Propagation","volume":"5 5","pages":"1340-1350"},"PeriodicalIF":3.5000,"publicationDate":"2024-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10555425","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"IEEE Open Journal of Antennas and Propagation","FirstCategoryId":"1085","ListUrlMain":"https://ieeexplore.ieee.org/document/10555425/","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ENGINEERING, ELECTRICAL & ELECTRONIC","Score":null,"Total":0}
引用次数: 0
Abstract
Unbalanced-fed Tightly-Coupled Dipole Arrays (TCDAs) allow for the realization of ultrawideband, wide-scanning phased arrays without the need for baluns, which may increase size, weight, and cost. However, unbalanced-fed TCDAs often have additional radiating modes and common-mode resonances which may degrade performance. In this paper, a scan impedance model is presented which describes performance in terms of a combination of even and odd monopole and dipole radiating modes. An intermodal coupling term is included to account for performance when scanning in the E-plane. Each mode is calculated individually in a full-wave solver and the model is then validated by comparing the proposed combination to a full simulation of the unbalanced-fed TCDA. A coaxial extension technique is then introduced to increase the impedance of the monopole-like radiating even mode, allowing the unbalanced-fed array to match the performance of the balanced-fed version without shorting posts or significant redesign of the elements or lattice.