By reductio ad absurdum, we show that a perfect power combiner of single-mode waveguides is impossible for incoherent input waves of the same frequency and same polarization as it is against the la ...
通过反证法，我们证明了对于同频率、同极化的非相干输入波，单模波导的完美功率合成器是不可能存在的。
{"title":"On the possibility of a perfect power combiner","authors":"Sailing He, Kexin Liu","doi":"10.2528/PIER16092302","DOIUrl":"https://doi.org/10.2528/PIER16092302","url":null,"abstract":"By reductio ad absurdum, we show that a perfect power combiner of single-mode waveguides is impossible for incoherent input waves of the same frequency and same polarization as it is against the la ...","PeriodicalId":54551,"journal":{"name":"Progress in Electromagnetics Research-Pier","volume":"60 1","pages":"1-6"},"PeriodicalIF":6.7,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81186945","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We aim to estimate the average dielectric properties of centimeter-scale volumes of biological tissues. A variety of approaches to measurement of dielectric properties of materials at microwave frequencies have been demonstrated in the literature and in practice. However, existing methods are not suitable for noninvasive measurement of in vivo biological tissues due to high property contrast with air, and the need to conform with the shape of the human body. To overcome this, a method of antenna calibration has been adapted and developed for use with an antenna system designed for biomedical applications, allowing for the estimation of permittivity and conductivity. This technique requires only two calibration procedures and does not require any special manufactured components. Simulated and measured results are presented between 3 to 8 GHz for materials with properties expected in biological tissues. Error bounds and an analysis of sources of error are provided.
{"title":"Antenna Calibration Method for Dielectric Property Estimation of Biological Tissues at Microwave Frequencies","authors":"David C. Garrett, J. Bourqui, E. Fear","doi":"10.2528/PIER16122204","DOIUrl":"https://doi.org/10.2528/PIER16122204","url":null,"abstract":"We aim to estimate the average dielectric properties of centimeter-scale volumes of biological tissues. A variety of approaches to measurement of dielectric properties of materials at microwave frequencies have been demonstrated in the literature and in practice. However, existing methods are not suitable for noninvasive measurement of in vivo biological tissues due to high property contrast with air, and the need to conform with the shape of the human body. To overcome this, a method of antenna calibration has been adapted and developed for use with an antenna system designed for biomedical applications, allowing for the estimation of permittivity and conductivity. This technique requires only two calibration procedures and does not require any special manufactured components. Simulated and measured results are presented between 3 to 8 GHz for materials with properties expected in biological tissues. Error bounds and an analysis of sources of error are provided.","PeriodicalId":54551,"journal":{"name":"Progress in Electromagnetics Research-Pier","volume":"57 1","pages":"73-87"},"PeriodicalIF":6.7,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75360704","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A self-contained electromagnetic theory is developed on a simplicial lattice. Instead of dealing with vectorial field, discrete exterior calculus (DEC) studies the discrete differential forms of electric and magnetic fields, and circumcenter dual is adopted to achieve diagonal Hodge star operators. In this paper, Gauss’ theorem and Stokes’ theorem are shown to be satisfied inherently within DEC. Many other electromagnetic theorems, such as Huygens’ principle, reciprocity theorem, and Poynting’s theorem, can also be derived on this simplicial lattice consistently with an appropriate definition of wedge product between cochains. The preservation of these theorems guarantees that this treatment of Maxwell’s equations will not lead to spurious solutions.
{"title":"Electromagnetic Theory with Discrete Exterior Calculus","authors":"Shu C. Chen, W. Chew","doi":"10.2528/PIER17051501","DOIUrl":"https://doi.org/10.2528/PIER17051501","url":null,"abstract":"A self-contained electromagnetic theory is developed on a simplicial lattice. Instead of dealing with vectorial field, discrete exterior calculus (DEC) studies the discrete differential forms of electric and magnetic fields, and circumcenter dual is adopted to achieve diagonal Hodge star operators. In this paper, Gauss’ theorem and Stokes’ theorem are shown to be satisfied inherently within DEC. Many other electromagnetic theorems, such as Huygens’ principle, reciprocity theorem, and Poynting’s theorem, can also be derived on this simplicial lattice consistently with an appropriate definition of wedge product between cochains. The preservation of these theorems guarantees that this treatment of Maxwell’s equations will not lead to spurious solutions.","PeriodicalId":54551,"journal":{"name":"Progress in Electromagnetics Research-Pier","volume":"38 1","pages":"59-78"},"PeriodicalIF":6.7,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85990510","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this paper we develop a higher order extraction method to accelerate the convergence in the computation of broadband Green’s function (BBGFL) for an arbitrary shaped homogeneous waveguide.The broadband Green’s function is based on modal expansions in which the modal field solutions are frequency independent. The higher order extraction is obtained by using three low wavenumbers in extraction. It gives a modal expansion of Broadband Green’s Function with 6th order convergence requiring fewer evanescent modes for convergence. Numerical results are illustrated for both lossless and lossy dielectric cases. The accuracy of results are verified with direct method of moment (MoM) and HFSS. The higher order BBGFL method is computationally efficient for broadband simulations.
{"title":"High Order Extractions of Broadband Green's Function with Low Wavenumber Extractions for Arbitrary Shaped Waveguide","authors":"T. Liao, K. Ding, L. Tsang","doi":"10.2528/PIER16101003","DOIUrl":"https://doi.org/10.2528/PIER16101003","url":null,"abstract":"In this paper we develop a higher order extraction method to accelerate the convergence in the computation of broadband Green’s function (BBGFL) for an arbitrary shaped homogeneous waveguide.The broadband Green’s function is based on modal expansions in which the modal field solutions are frequency independent. The higher order extraction is obtained by using three low wavenumbers in extraction. It gives a modal expansion of Broadband Green’s Function with 6th order convergence requiring fewer evanescent modes for convergence. Numerical results are illustrated for both lossless and lossy dielectric cases. The accuracy of results are verified with direct method of moment (MoM) and HFSS. The higher order BBGFL method is computationally efficient for broadband simulations.","PeriodicalId":54551,"journal":{"name":"Progress in Electromagnetics Research-Pier","volume":"207 0 1","pages":"7-20"},"PeriodicalIF":6.7,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80627296","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"State-of-the-Art Electromagnetics Research in Electric and Hybrid Vehicles (Invited Paper)","authors":"K. Chau, C. Jiang, W. Han, Christopher H. T. Lee","doi":"10.2528/PIER17090407","DOIUrl":"https://doi.org/10.2528/PIER17090407","url":null,"abstract":"","PeriodicalId":54551,"journal":{"name":"Progress in Electromagnetics Research-Pier","volume":"12 1","pages":"139-157"},"PeriodicalIF":6.7,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73111403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
L. Peng, Xiao-xia Zheng, Kewen Wang, Shuaifei Sang, Yuntian Chen, Gaofeng Wang
In this paper, we study the design and homogenization of bianisotropic metamaterials originated from planar split-ring resonators, which would potentially meet the requirements of the emerging photonic topological insulators and some other types of extotic photonic materials with nontrivial states. We show that the off-diagonal elements in the magneto-electric tensor can be realized by combining the planar split-ring resonators with different orientations. To ease the fabrication process, a layer-by-layer design of metamaterials with desired bianisotropy is proposed. The design and homogenization procedure of such metamaterials are verified through effective parameter retrieval approach and computer based simulation. With the proposed structure, the complex magneto-electric coupling is realized in layered structures through planar techniques, which may be useful in the terahertz and optical range.
{"title":"Layer-by-Layer Design of Bianisotropic Metamaterial and its Homogenization","authors":"L. Peng, Xiao-xia Zheng, Kewen Wang, Shuaifei Sang, Yuntian Chen, Gaofeng Wang","doi":"10.2528/PIER17041502","DOIUrl":"https://doi.org/10.2528/PIER17041502","url":null,"abstract":"In this paper, we study the design and homogenization of bianisotropic metamaterials originated from planar split-ring resonators, which would potentially meet the requirements of the emerging photonic topological insulators and some other types of extotic photonic materials with nontrivial states. We show that the off-diagonal elements in the magneto-electric tensor can be realized by combining the planar split-ring resonators with different orientations. To ease the fabrication process, a layer-by-layer design of metamaterials with desired bianisotropy is proposed. The design and homogenization procedure of such metamaterials are verified through effective parameter retrieval approach and computer based simulation. With the proposed structure, the complex magneto-electric coupling is realized in layered structures through planar techniques, which may be useful in the terahertz and optical range.","PeriodicalId":54551,"journal":{"name":"Progress in Electromagnetics Research-Pier","volume":"64 1","pages":"39-47"},"PeriodicalIF":6.7,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73706095","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The study and design of a wideband aperture coupled microstrip patch array is presented. The proposed design considers the 2.4 to 3 GHz frequency range but may be adapted to other frequencies. A 16 element planar array of the size of about 400 mm by 400 mm by 12.5 mm provides measured gain from 15.4 to 16.8 dBi and Side-Lobe Level (SLL) from 15.3 to 20.7 dB without a reflector within the 2.4 to 3GHz frequency range. With a reflector significant increase in F/B is obtained but at the expense of higher SLL.
{"title":"Wideband Aperture Coupled Patch Array Antennas - High Gain, Low Side Lobe Design","authors":"Dhruva Poduval, Mohammod Ali","doi":"10.2528/PIER17092904","DOIUrl":"https://doi.org/10.2528/PIER17092904","url":null,"abstract":"The study and design of a wideband aperture coupled microstrip patch array is presented. The proposed design considers the 2.4 to 3 GHz frequency range but may be adapted to other frequencies. A 16 element planar array of the size of about 400 mm by 400 mm by 12.5 mm provides measured gain from 15.4 to 16.8 dBi and Side-Lobe Level (SLL) from 15.3 to 20.7 dB without a reflector within the 2.4 to 3GHz frequency range. With a reflector significant increase in F/B is obtained but at the expense of higher SLL.","PeriodicalId":54551,"journal":{"name":"Progress in Electromagnetics Research-Pier","volume":"16 1","pages":"71-87"},"PeriodicalIF":6.7,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85221734","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ming Fang, Zhixiang Huang, W. Sha, X. Xiong, Xianliang Wu
Applications of metallic metamaterials have generated significant interest in recent years. Electromagnetic behavior of metamaterials in the optical range is usually characterized by a local-linear response. In this article, we develop a finite-difference time-domain (FDTD) solution of the hydrodynamic model that describes a free electron gas in metals. Extending beyond the local-linear response, the hydrodynamic model enables numerical investigation of nonlocal and nonlinear interactions between electromagnetic waves and metallic metamaterials. By explicitly imposing the current continuity constraint, the proposed model is solved in a self-consistent manner. Charge, energy and angular momentum conservation laws of high-order harmonic generation have been demonstrated for the first time by the Maxwell-hydrodynamic FDTD model. The model yields nonlinear optical responses for complex metallic metamaterials irradiated by a variety of waveforms. Consequently, the multiphysics model opens up unique opportunities for characterizing and designing nonlinear nanodevices.
{"title":"Full Hydrodynamic Model of Nonlinear Electromagnetic Response in Metallic Metamaterials (Invited Paper)","authors":"Ming Fang, Zhixiang Huang, W. Sha, X. Xiong, Xianliang Wu","doi":"10.2528/PIER16100401","DOIUrl":"https://doi.org/10.2528/PIER16100401","url":null,"abstract":"Applications of metallic metamaterials have generated significant interest in recent years. Electromagnetic behavior of metamaterials in the optical range is usually characterized by a local-linear response. In this article, we develop a finite-difference time-domain (FDTD) solution of the hydrodynamic model that describes a free electron gas in metals. Extending beyond the local-linear response, the hydrodynamic model enables numerical investigation of nonlocal and nonlinear interactions between electromagnetic waves and metallic metamaterials. By explicitly imposing the current continuity constraint, the proposed model is solved in a self-consistent manner. Charge, energy and angular momentum conservation laws of high-order harmonic generation have been demonstrated for the first time by the Maxwell-hydrodynamic FDTD model. The model yields nonlinear optical responses for complex metallic metamaterials irradiated by a variety of waveforms. Consequently, the multiphysics model opens up unique opportunities for characterizing and designing nonlinear nanodevices.","PeriodicalId":54551,"journal":{"name":"Progress in Electromagnetics Research-Pier","volume":"89 1","pages":"63-78"},"PeriodicalIF":6.7,"publicationDate":"2016-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90996174","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this paper, an efficient lightweight double-layer microwave absorber with impedance- matching structure at X-Ku bands was designed, optimized and implemented. First, genetic algorithm (GA) was considered to optimize the thicknesses and material properties for better absorption of the incident electromagnetic wave and reduction of radar cross section (RCS). Next, with the aid of the obtained dielectric and magnetic properties, the microwave absorber was fabricated from magneto- dielectric composite materials besides a natural rubber. Finally, the analytical and numerical results were compared with the measurements to check the validity of the design. Experiments showed that the reflection coefficient for each layer backed with a metallic sheet was insufficient; however, for the double layer absorber, the reflectivity measurement values reached up to −28 dB in the case of normal incidence and −17 dB for oblique incidence.
{"title":"Design of Compact Double-Layer Microwave Absorber for X-Ku Bands Using Genetic Algorithm","authors":"H. El-Hakim, K. Mahmoud, A. A. Abdelaziz","doi":"10.2528/PIERB15111702","DOIUrl":"https://doi.org/10.2528/PIERB15111702","url":null,"abstract":"In this paper, an efficient lightweight double-layer microwave absorber with impedance- matching structure at X-Ku bands was designed, optimized and implemented. First, genetic algorithm (GA) was considered to optimize the thicknesses and material properties for better absorption of the incident electromagnetic wave and reduction of radar cross section (RCS). Next, with the aid of the obtained dielectric and magnetic properties, the microwave absorber was fabricated from magneto- dielectric composite materials besides a natural rubber. Finally, the analytical and numerical results were compared with the measurements to check the validity of the design. Experiments showed that the reflection coefficient for each layer backed with a metallic sheet was insufficient; however, for the double layer absorber, the reflectivity measurement values reached up to −28 dB in the case of normal incidence and −17 dB for oblique incidence.","PeriodicalId":54551,"journal":{"name":"Progress in Electromagnetics Research-Pier","volume":"1 1","pages":"157-168"},"PeriodicalIF":6.7,"publicationDate":"2016-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76128616","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
E. Rothwell, J. L. Frasch, Sean M. Ellison, P. Chahal, R. Ouedraogo
A method for predicting the behavior of the permittivity and permeability of an engineered material by examining the measured S-parameters of a material sample is devised, assuming that the sample is lossless and symmetric. The S-parameter conditions under which the material parameters extracted using the Nicolson-Ross-Weir method may be associated with a lossless homogeneous material are described. Also, the relationship between the signs of the real and imaginary parts of the permittivity and permeability are determined, both when the extracted material parameters are real and when they are complex. In particular, the conditions under which metamaterials exhibit double-negative properties may be predicted from the S-parameters of a metamaterial sample. The relationships between material characteristics and the S-parameters should prove useful when synthesizing materials to have certain desired properties. Examples, both from experiment and simulation, demonstrate that the relationships may be used to understand the behavior of several different categories of engineered materials, even when the materials have appreciable loss.
{"title":"Analysis of the Nicolson-Ross-Weir Method for Characterizing the Electromagnetic Properties of Engineered Materials","authors":"E. Rothwell, J. L. Frasch, Sean M. Ellison, P. Chahal, R. Ouedraogo","doi":"10.2528/PIER16071706","DOIUrl":"https://doi.org/10.2528/PIER16071706","url":null,"abstract":"A method for predicting the behavior of the permittivity and permeability of an engineered material by examining the measured S-parameters of a material sample is devised, assuming that the sample is lossless and symmetric. The S-parameter conditions under which the material parameters extracted using the Nicolson-Ross-Weir method may be associated with a lossless homogeneous material are described. Also, the relationship between the signs of the real and imaginary parts of the permittivity and permeability are determined, both when the extracted material parameters are real and when they are complex. In particular, the conditions under which metamaterials exhibit double-negative properties may be predicted from the S-parameters of a metamaterial sample. The relationships between material characteristics and the S-parameters should prove useful when synthesizing materials to have certain desired properties. Examples, both from experiment and simulation, demonstrate that the relationships may be used to understand the behavior of several different categories of engineered materials, even when the materials have appreciable loss.","PeriodicalId":54551,"journal":{"name":"Progress in Electromagnetics Research-Pier","volume":"123 1","pages":"31-47"},"PeriodicalIF":6.7,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85686574","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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