IEEE Antennas and Propagation Society International Symposium 1997. Digest最新文献

Finite difference time domain modeling of an indoor antenna chamber with phased planar array 相控阵室内天线室的时域有限差分建模

IEEE Antennas and Propagation Society International Symposium 1997. Digest Pub Date : 1997-07-13 DOI: 10.1109/APS.1997.631470

Scott E. Metker, R. Luebbers, Joseph, Schuster

引用次数: 1

Critical analysis of Yee and matched layers absorbing boundary conditions for 2-D and 3-D applications of the FDTD method FDTD法在二维和三维应用中Yee和匹配层吸收边界条件的临界分析

IEEE Antennas and Propagation Society International Symposium 1997. Digest Pub Date : 1997-07-13 DOI: 10.1109/APS.1997.631710

C.-W.P. Huang, A. Elsherbeni, C.E. Smith

引用次数: 0

Electromagnetic pulse propagation and scattering from terrain: experimental observation and comparison with theory 电磁脉冲在地形上的传播与散射:实验观察与理论比较

IEEE Antennas and Propagation Society International Symposium 1997. Digest Pub Date : 1997-07-13 DOI: 10.1109/APS.1997.625529

L. Zurk, S. Coutts

{"title":"Electromagnetic pulse propagation and scattering from terrain: experimental observation and comparison with theory","authors":"L. Zurk, S. Coutts","doi":"10.1109/APS.1997.625529","DOIUrl":"https://doi.org/10.1109/APS.1997.625529","url":null,"abstract":"We consider the problem of electromagnetic propagation over variable terrain from both an experimental and a theoretical standpoint. The experimental data were collected by MIT Lincoln Laboratory during an airborne multipath propagation experiment in the fall of 1996. The experiment utilized two planes equipped with UHF and VHF antennas and explored the time-difference-of-arrival (TDOA) observed between the direct and reflected signal in a pulsed radar system. The data was collected over a variety of terrains in New Mexico and Maine ranging from smooth desert floor to rough mountainous terrain. In this paper measurements from selected data sets are compared to theoretical results from Lincoln Laboratory propagation code SEKE which has been modified for wide bandwidth signals using Fourier techniques. This work may be useful for the evaluation of multipath-based height-finding techniques for airborne radars. By estimating the TDOA between the direct and reflected signals one can estimate the target height geometrically. This height-finding technique requires sufficient signal bandwidth to resolve the multiple pulses as well as a propagation environment that will support specular reflections. The goal of this work is to increase our understanding of the propagation environment and to improve our modeling capacity for wide-bandwidth signals over various terrains.","PeriodicalId":283897,"journal":{"name":"IEEE Antennas and Propagation Society International Symposium 1997. Digest","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120972573","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Inclusion of finite substrate effects in the analysis of printed antennas and MICs by the CGF technique 用CGF技术分析印刷天线和MICs的有限基板效应

IEEE Antennas and Propagation Society International Symposium 1997. Digest Pub Date : 1997-07-13 DOI: 10.1109/APS.1997.631537

R. Faraji-Dana, Y. Chow

引用次数: 1

Time domain vector potential formulation for the solution of electromagnetic problems 求解电磁问题的时域矢量位势公式

IEEE Antennas and Propagation Society International Symposium 1997. Digest Pub Date : 1997-07-13 DOI: 10.1109/75.720465

F. D. Flaviis, M. Noro, Rodolfo E. Diaz, Giorgio Franceschetti, Nicolaos G. Alexopoulos

引用次数: 20

FDTD characterization of radiation patterns from flexible microstrip applicators 柔性微带应用器辐射图样的FDTD表征

IEEE Antennas and Propagation Society International Symposium 1997. Digest Pub Date : 1997-07-13 DOI: 10.1109/APS.1997.631471

F. Rossetto, P. Stauffer, D. Deardorff, G. B. Gentili, M. Leoncini

{"title":"FDTD characterization of radiation patterns from flexible microstrip applicators","authors":"F. Rossetto, P. Stauffer, D. Deardorff, G. B. Gentili, M. Leoncini","doi":"10.1109/APS.1997.631471","DOIUrl":"https://doi.org/10.1109/APS.1997.631471","url":null,"abstract":"The FDTD numerical method has been used to calculate the radiation patterns from 915 MHz dual concentric conductor (DCC) applicators which were designed for use in superficial hyperthermia applications. Results are given for radiation from single 2 cm square apertures considering several different electromagnetic feed and tissue coupling configurations, and from multiple element arrays of six adjacent apertures. Radiated electric field distributions are expressed as specific absorption rate (SAR) patterns in a lossy muscle tissue load. The power deposition patterns are illustrated in planes 1 cm deep in tissue (e.g. just under the superficial tumor target) and in a vertical cross section plane cutting through the applicator and layered tissue load. The results demonstrate that when coupled with a 5 mm thick water bolus layer, the thin, flexible and lightweight planar DCC antennas produce effective heating out to the periphery of each aperture to a depth of approximately 1 cm in realistic tissue loads, and may be combined into arrays for relatively uniform heating of larger surface areas with >50% of maximum power deposition extending out to the perimeter of the array.","PeriodicalId":283897,"journal":{"name":"IEEE Antennas and Propagation Society International Symposium 1997. Digest","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124998988","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6

A novel dual polarized aperture coupled patch element with a single layer feed network and high isolation 一种具有单层馈电网络和高隔离度的新型双极化孔径耦合贴片元件

IEEE Antennas and Propagation Society International Symposium 1997. Digest Pub Date : 1997-07-13 DOI: 10.1109/APS.1997.625403

Bjorn Lindmark Allgon

{"title":"A novel dual polarized aperture coupled patch element with a single layer feed network and high isolation","authors":"Bjorn Lindmark Allgon","doi":"10.1109/APS.1997.625403","DOIUrl":"https://doi.org/10.1109/APS.1997.625403","url":null,"abstract":"The aperture coupled patch geometry has been extended to dual polarization by several authors. In Tsao et al. (1988) a cross-shaped slot is fed by a balanced feed network which allows for a high degree of isolation. However, the balanced feed calls for an air-bridge which complicates both the design process and the manufacture. An alleviation to this problem is to separate the two channels onto two different substrate layers separated by the ground plane. In this case the disadvantage is increased cost. Another solution with a single layer feed is presented in Brachat and Baracco (1995) where one channel feeds a single slot centered under the patch whereas the other channel feeds two separate slots placed near the edges of the patch. Our experience is that with this geometry it is hard to achieve a well-matched broadband design since the slots near the edge of the patch present very low coupling. All the above geometries maintain symmetry with respect to the two principal planes if we ignore the small spurious coupling from feed lines in the vicinity of the aperture. We propose to reduce the symmetry to only one principal plane which turns out to be sufficient for high isolation and low cross-polarization. The advantage is that only one layer of feed network is needed, with no air-bridges required. In addition the aperture position is centered under the patch. An important application for dual polarized antennas is base station antennas. We have therefore designed and measured an element for the PCS band (1.85-1.99 GHz).","PeriodicalId":283897,"journal":{"name":"IEEE Antennas and Propagation Society International Symposium 1997. Digest","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125949090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 62

Analysis of antennas on curved multilayer structures by using the GIDMULT routine 利用GIDMULT程序分析弯曲多层结构上的天线

IEEE Antennas and Propagation Society International Symposium 1997. Digest Pub Date : 1997-07-13 DOI: 10.1109/APS.1997.631453

P. Kildal, Z. Šipuš, M. Johansson

引用次数: 2

Fast direct solution algorithm for electromagnetic scattering from 3D planar and quasi-planar geometries 三维平面和准平面几何电磁散射的快速直接求解算法

IEEE Antennas and Propagation Society International Symposium 1997. Digest Pub Date : 1997-07-13 DOI: 10.1109/APS.1997.630087

L. Gurel, Weng Cho Chew

引用次数: 3

Efficient high-order discretization schemes for integral equation methods 积分方程方法的高效高阶离散化方法

IEEE Antennas and Propagation Society International Symposium 1997. Digest Pub Date : 1997-07-13 DOI: 10.1109/APS.1997.631613

S. Gedney, J. Ottusch, P. Petre, J. Visher, S. Wandzura

{"title":"Efficient high-order discretization schemes for integral equation methods","authors":"S. Gedney, J. Ottusch, P. Petre, J. Visher, S. Wandzura","doi":"10.1109/APS.1997.631613","DOIUrl":"https://doi.org/10.1109/APS.1997.631613","url":null,"abstract":"A high-order method is a method that provides extra digits of accuracy with only a modest increase in computational cost. A number of method of moment (MoM) techniques based on high-order basis and testing functions have been presented in the literature. Characteristically, these methods result in a substantial increase in precomputational cost principally due to the expensive numerical integration required for near interactions. This can be accelerated through the use of specialized quadrature schemes when available. Unfortunately, performing the double integration numerically over high-order functions can still be quite computationally intensive. A novel high-order technique based on a locally-corrected Nystrom scheme combined with advanced quadrature schemes is presented. It is shown that this method truly demonstrates high-order convergence for the solution of electromagnetic scattering problems with comparable computational cost to low-order schemes. The elegance of this technique is in its simplicity and ease of implementation. However, the power of the method is its ability to inexpensively provide true high-order convergence.","PeriodicalId":283897,"journal":{"name":"IEEE Antennas and Propagation Society International Symposium 1997. Digest","volume":"92 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1997-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115573952","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 21