Pub Date : 2023-02-17DOI: 10.1080/02726343.2023.2192104
Long Jin, Zhibin He, Jiuyang Xiao, Yao Sun, Yangmiao Lin, Ruohan Zhang
ABSTRACT A broadside direction gain-enhanced low-cost dual-polarized microstrip patch antenna has been presented. The proposed antenna consists of a slot-loaded cross-shaped patch and shorting pins. The orthogonal polarized radiating elements works in TM05 and TM12, meanwhile slot-loaded excite TM01. The equivalent magnetic currents (EMCs) amplitude, frequency, and flow direction of the TM12 are controlled by shorting pins to form the broadside gain enhancement. The superposition of them can enhance the gain in the broadside direction. The proposed antenna is coaxial feed. The substrate is divided into two layers: air and FR4. A copper column is added to the air layer to greatly improve the polarized isolation of the antenna. The size of the proposed antenna is 2.29λ 0×2.29λ 0×0.069λ 0 (λ 0 is the wavelength of free space at the central frequency). The simulated maximum realized gain is 12.59 dB, and the realized gain is better than 11.53 dB in operating band. The measured maximum realized gain is 12.05 dB, and the realized gain is better than 10.04 dB. The dual-polarized microstrip patch antenna has the advantages of low cost and high gain, which can be used in the modern wireless communication system.
{"title":"A novel dual-polarized gain-enhanced microstrip patch antenna","authors":"Long Jin, Zhibin He, Jiuyang Xiao, Yao Sun, Yangmiao Lin, Ruohan Zhang","doi":"10.1080/02726343.2023.2192104","DOIUrl":"https://doi.org/10.1080/02726343.2023.2192104","url":null,"abstract":"ABSTRACT A broadside direction gain-enhanced low-cost dual-polarized microstrip patch antenna has been presented. The proposed antenna consists of a slot-loaded cross-shaped patch and shorting pins. The orthogonal polarized radiating elements works in TM05 and TM12, meanwhile slot-loaded excite TM01. The equivalent magnetic currents (EMCs) amplitude, frequency, and flow direction of the TM12 are controlled by shorting pins to form the broadside gain enhancement. The superposition of them can enhance the gain in the broadside direction. The proposed antenna is coaxial feed. The substrate is divided into two layers: air and FR4. A copper column is added to the air layer to greatly improve the polarized isolation of the antenna. The size of the proposed antenna is 2.29λ 0×2.29λ 0×0.069λ 0 (λ 0 is the wavelength of free space at the central frequency). The simulated maximum realized gain is 12.59 dB, and the realized gain is better than 11.53 dB in operating band. The measured maximum realized gain is 12.05 dB, and the realized gain is better than 10.04 dB. The dual-polarized microstrip patch antenna has the advantages of low cost and high gain, which can be used in the modern wireless communication system.","PeriodicalId":50542,"journal":{"name":"Electromagnetics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48561161","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-02DOI: 10.1080/02726343.2023.2177373
F. Ghiasvand
ABSTRACT UWB dual polarization azimuth plane monopulse feed-reflector antenna is presented. Quadridge open ended waveguide working in frequency range from 6 to 12 GHz is proposed as feed for Cassegrain reflector. The feed phase center distance is 0.65 and 1.3 at lowest and highest operating frequency respectively. Sum (Σ) and Diff (Δ) radiation pattern of the feed array are measured in anechoic chamber using same electrical length coaxial cable and 180°Coupler. The results are in good agreement (vertical and horizontal polarizations) with numerical simulation especially for the main beam. To enhance gain value, 50 cm reflector antenna has been used. A proper crossover is achieved by controlling F/D ratio of the equivalent reflector. A compact Cassegrain reflector compatible to feed array is designed and fabricated. The radiation characteristics measurements of the feed-reflector system have been performed using outdoor measurement setup. By ignoring coupler insertion loss, Sum (Diff) gain range is between 24.8 (17) dBi at 6 GHz and 31.7 (29.5) dBi at 12 GHz. Cross pol and null depth better than −31.5 and −24 have been obtained.
{"title":"UWB full polarization single-plane monopulse reflector antenna","authors":"F. Ghiasvand","doi":"10.1080/02726343.2023.2177373","DOIUrl":"https://doi.org/10.1080/02726343.2023.2177373","url":null,"abstract":"ABSTRACT UWB dual polarization azimuth plane monopulse feed-reflector antenna is presented. Quadridge open ended waveguide working in frequency range from 6 to 12 GHz is proposed as feed for Cassegrain reflector. The feed phase center distance is 0.65 and 1.3 at lowest and highest operating frequency respectively. Sum (Σ) and Diff (Δ) radiation pattern of the feed array are measured in anechoic chamber using same electrical length coaxial cable and 180°Coupler. The results are in good agreement (vertical and horizontal polarizations) with numerical simulation especially for the main beam. To enhance gain value, 50 cm reflector antenna has been used. A proper crossover is achieved by controlling F/D ratio of the equivalent reflector. A compact Cassegrain reflector compatible to feed array is designed and fabricated. The radiation characteristics measurements of the feed-reflector system have been performed using outdoor measurement setup. By ignoring coupler insertion loss, Sum (Diff) gain range is between 24.8 (17) dBi at 6 GHz and 31.7 (29.5) dBi at 12 GHz. Cross pol and null depth better than −31.5 and −24 have been obtained. ","PeriodicalId":50542,"journal":{"name":"Electromagnetics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46439615","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-02DOI: 10.1080/02726343.2023.2177390
Shuqi Wang, Haonan Zhang, Zexi Li
ABSTRACT In order to improve the performance of 5 G Millimeter wave, a new gap-coupled fed ultra-wideband circularly polarized antenna is proposed. Firstly, by fabricating the top structure of the slot antenna ，a C-shaped patch structure can adjust the surface transverse current as well as the longitudinal current to generate circularly polarized waves; then the feed structure at the bottom layer of the antenna is designed and resonance is generated with the top layer of the antenna to expand bandwidth. From the simulation and the measurement results can know that the −10 dB impedance bandwidth of the antenna is 19.21 GHz−45.50 GHz (81.25%); the 3 dB circularly polarized axial ratio (AR) bandwidth is 20.59 GHz−38.33 GHz (60.2%), with ultra-broadband circular polarization performance. The designed antenna has a simple structure, small size, low profile and wide working bandwidth, which can fully include N257, N258 and N261 bands, and has a good application prospect in 5 G communication.
{"title":"Ultra-wideband circularly polarized millimeter wave antenna based on adjacent coupled feed","authors":"Shuqi Wang, Haonan Zhang, Zexi Li","doi":"10.1080/02726343.2023.2177390","DOIUrl":"https://doi.org/10.1080/02726343.2023.2177390","url":null,"abstract":"ABSTRACT In order to improve the performance of 5 G Millimeter wave, a new gap-coupled fed ultra-wideband circularly polarized antenna is proposed. Firstly, by fabricating the top structure of the slot antenna ，a C-shaped patch structure can adjust the surface transverse current as well as the longitudinal current to generate circularly polarized waves; then the feed structure at the bottom layer of the antenna is designed and resonance is generated with the top layer of the antenna to expand bandwidth. From the simulation and the measurement results can know that the −10 dB impedance bandwidth of the antenna is 19.21 GHz−45.50 GHz (81.25%); the 3 dB circularly polarized axial ratio (AR) bandwidth is 20.59 GHz−38.33 GHz (60.2%), with ultra-broadband circular polarization performance. The designed antenna has a simple structure, small size, low profile and wide working bandwidth, which can fully include N257, N258 and N261 bands, and has a good application prospect in 5 G communication.","PeriodicalId":50542,"journal":{"name":"Electromagnetics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48620309","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-02DOI: 10.1080/02726343.2023.2177393
Hongjie He, Ya Zhang, Ke-Yun Li
ABSTRACT To accurately simulate the electromagnetic scattering from a three-dimensional (3-D) coated object half-buried in perfectly electrically conductor (PEC) rough surface, an efficient method combining the 3-D vector finite element method-boundary integral method (FEM-BIM) with fast multipole method (FMM) is proposed in this paper. FEM is used to model the coated object and the multiple interactions between the half-buried object and rough surface are handled by FMM-enhanced BIM. According to the characteristics of the FEM-BIM matrix equations, a hybrid solver is adopted to solve the matrix equations. In addition, OpenMP parallel acceleration technique is used in the numerical code to accelerate the intensive computations of the prediction process. The accuracy and efficiency of our numerical code are validated by multilevel fast multipole method (MLFMM) in FEKO for both TE and TM polarizations.
{"title":"An efficient method for analysis of electromagnetic scattering from a 3-D coated object half-buried in PEC rough surface","authors":"Hongjie He, Ya Zhang, Ke-Yun Li","doi":"10.1080/02726343.2023.2177393","DOIUrl":"https://doi.org/10.1080/02726343.2023.2177393","url":null,"abstract":"ABSTRACT To accurately simulate the electromagnetic scattering from a three-dimensional (3-D) coated object half-buried in perfectly electrically conductor (PEC) rough surface, an efficient method combining the 3-D vector finite element method-boundary integral method (FEM-BIM) with fast multipole method (FMM) is proposed in this paper. FEM is used to model the coated object and the multiple interactions between the half-buried object and rough surface are handled by FMM-enhanced BIM. According to the characteristics of the FEM-BIM matrix equations, a hybrid solver is adopted to solve the matrix equations. In addition, OpenMP parallel acceleration technique is used in the numerical code to accelerate the intensive computations of the prediction process. The accuracy and efficiency of our numerical code are validated by multilevel fast multipole method (MLFMM) in FEKO for both TE and TM polarizations.","PeriodicalId":50542,"journal":{"name":"Electromagnetics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48316798","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-02DOI: 10.1080/02726343.2023.2177394
Hüseyin Özmen, M. B. Kurt
ABSTRACT In this study, a breast phantom measurement system based on radar-based microwave imaging technique is proposed. For this purpose, a small-size Vivaldi antenna with high gain and ultra-wide band is designed. The antenna bandwidth is in the range of 3–10.6 GHz, and the maximum realized gain is 8.5 dB. The size of the antenna is 36 × 36 mm2, and FR4 was used as dielectric material. Bandwidth and gain are increased by using edge slots. After the antenna hardware had been manufactured with PCB printed circuit technology, a mechanism was developed to measure breast phantom. After the measurement process is completed, a computer program converts the collected signals into images. For the testing of the system, canola oil was used as a phantom and the object in the oil was successfully imaged.
{"title":"A novel gain enhanced Vivaldi antenna for a breast phantom measurement system","authors":"Hüseyin Özmen, M. B. Kurt","doi":"10.1080/02726343.2023.2177394","DOIUrl":"https://doi.org/10.1080/02726343.2023.2177394","url":null,"abstract":"ABSTRACT In this study, a breast phantom measurement system based on radar-based microwave imaging technique is proposed. For this purpose, a small-size Vivaldi antenna with high gain and ultra-wide band is designed. The antenna bandwidth is in the range of 3–10.6 GHz, and the maximum realized gain is 8.5 dB. The size of the antenna is 36 × 36 mm2, and FR4 was used as dielectric material. Bandwidth and gain are increased by using edge slots. After the antenna hardware had been manufactured with PCB printed circuit technology, a mechanism was developed to measure breast phantom. After the measurement process is completed, a computer program converts the collected signals into images. For the testing of the system, canola oil was used as a phantom and the object in the oil was successfully imaged.","PeriodicalId":50542,"journal":{"name":"Electromagnetics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41360285","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-02DOI: 10.1080/02726343.2023.2177391
Yi Ren, Jianmei Zhou
ABSTRACT This paper presents a novel approach to accurately simulate the low frequency electromagnetic scattering of a homogeneous dielectric object in layered medium. The N-Muller surface integral equation (SIE) is utilized for accurate electromagnetic modeling at low frequency with a properly designed coefficient to cancel frequency singularity. Matrix-friendly layered medium Green’s functions are adopted and integrated into SIE to account for the effects of the inhomogeneous background. By using Galerkin method and rooftop basis functions, a well-conditioned impedance matrix is obtained and a rapidly converging iterative solution is achieved for low frequencies. Numerical results are provided to validate the proposed method and investigate its properties.
{"title":"Low frequency scattering simulation of homogeneous objects in layered medium by Muller formed SIE","authors":"Yi Ren, Jianmei Zhou","doi":"10.1080/02726343.2023.2177391","DOIUrl":"https://doi.org/10.1080/02726343.2023.2177391","url":null,"abstract":"ABSTRACT This paper presents a novel approach to accurately simulate the low frequency electromagnetic scattering of a homogeneous dielectric object in layered medium. The N-Muller surface integral equation (SIE) is utilized for accurate electromagnetic modeling at low frequency with a properly designed coefficient to cancel frequency singularity. Matrix-friendly layered medium Green’s functions are adopted and integrated into SIE to account for the effects of the inhomogeneous background. By using Galerkin method and rooftop basis functions, a well-conditioned impedance matrix is obtained and a rapidly converging iterative solution is achieved for low frequencies. Numerical results are provided to validate the proposed method and investigate its properties.","PeriodicalId":50542,"journal":{"name":"Electromagnetics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47065412","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-02DOI: 10.1080/02726343.2023.2177388
T. Purnamirza, Ranggi Rian Syaputra, J. M. Shardarbekovich, Imran Mohd Ibrahim, K. A. Batyrbekovich, M. Mulyono, Depriwana Rahmi, Halim Mudia
ABSTRACT An original design of a multibeam Radial Line Slot Array (RLSA) antenna having two beams directed to the broadside and two beams directed to the backside is discussed in this research. The uniqueness of this design is the implementation of multibeam as a half-cut RLSA instead of a full-circle RLSA, which aims to make them more suitable for smaller devices. In order to produce a beam to the backside, the slots were placed on the backside ground plane. Furthermore, the use of the half-circle RLSA and the backside ground plane to generate the beam disrupted the power flow within the antenna’s cavity, which caused a problem of center frequency shift. A frequency design shift technique is then proposed to overcome this problem in this research with the modeling and simulation of 120 four-beams half RLSA in order to determine the most efficient model to be fabricated. The measurements carried out to verify the accuracy of the fabricated model were in good agreement with the simulation results and proved the validity of the antenna design. The result shows the possibility and effectiveness of designing four symmetrical beam antennas with gain of 8.1 dBi, directions of 60°, 150°, 210°, and 330°, and beamwidth of 22°. The gain of 8.1 dBi is 9 dB less than the gain of a single beam antenna, which is consistent with the theory of beam splitting. Moreover, the antenna offers low reflection and broad bandwidth for Wi-Fi needs.
{"title":"Multibeam half radial line slot array (RLSA) antennas","authors":"T. Purnamirza, Ranggi Rian Syaputra, J. M. Shardarbekovich, Imran Mohd Ibrahim, K. A. Batyrbekovich, M. Mulyono, Depriwana Rahmi, Halim Mudia","doi":"10.1080/02726343.2023.2177388","DOIUrl":"https://doi.org/10.1080/02726343.2023.2177388","url":null,"abstract":"ABSTRACT An original design of a multibeam Radial Line Slot Array (RLSA) antenna having two beams directed to the broadside and two beams directed to the backside is discussed in this research. The uniqueness of this design is the implementation of multibeam as a half-cut RLSA instead of a full-circle RLSA, which aims to make them more suitable for smaller devices. In order to produce a beam to the backside, the slots were placed on the backside ground plane. Furthermore, the use of the half-circle RLSA and the backside ground plane to generate the beam disrupted the power flow within the antenna’s cavity, which caused a problem of center frequency shift. A frequency design shift technique is then proposed to overcome this problem in this research with the modeling and simulation of 120 four-beams half RLSA in order to determine the most efficient model to be fabricated. The measurements carried out to verify the accuracy of the fabricated model were in good agreement with the simulation results and proved the validity of the antenna design. The result shows the possibility and effectiveness of designing four symmetrical beam antennas with gain of 8.1 dBi, directions of 60°, 150°, 210°, and 330°, and beamwidth of 22°. The gain of 8.1 dBi is 9 dB less than the gain of a single beam antenna, which is consistent with the theory of beam splitting. Moreover, the antenna offers low reflection and broad bandwidth for Wi-Fi needs.","PeriodicalId":50542,"journal":{"name":"Electromagnetics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2023-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41669902","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-17DOI: 10.1080/02726343.2022.2161705
H. Hao, Huangxia Xu, Qinxuan Ling, Yunrui Wang
ABSTRACT According to the development demand for radio frequency module function integration, a filtering power divider with wideband external suppression and high isolation is designed based on the traditional Wilkinson power divider. The working mechanism of the device is analyzed by using the odd-even mode method. Utilizing the branch loading on the coupled-line and the addition of a step impedance open-circuit stub, we can realize the filtering function, widen the passband bandwidth, and improve the performance of stopband rejection. Through the bending of microstrip line between the input and output parts, it is conducive to the physical access of isolation resistance, and the isolation performance between output ports is improved. The research results show that the central working frequency of the filtering power divider is 2.85 GHz (f 0). The 3 dB bandwidth width is 1.51 GHz, and the relative bandwidth is 52.9%. The out-of-band suppression is lower than −20 dB in the range of 3.96 to 11.1 GHz (3.89f 0), and the isolation between output ports is lower than −24.4 dB in the ultra-wideband range of DC to 12 GHz. The device has excellent application prospects in radio frequency communication systems, such as amplifiers and antenna arrays.
{"title":"Design of a planar filtering power divider with wide-stopband suppression","authors":"H. Hao, Huangxia Xu, Qinxuan Ling, Yunrui Wang","doi":"10.1080/02726343.2022.2161705","DOIUrl":"https://doi.org/10.1080/02726343.2022.2161705","url":null,"abstract":"ABSTRACT According to the development demand for radio frequency module function integration, a filtering power divider with wideband external suppression and high isolation is designed based on the traditional Wilkinson power divider. The working mechanism of the device is analyzed by using the odd-even mode method. Utilizing the branch loading on the coupled-line and the addition of a step impedance open-circuit stub, we can realize the filtering function, widen the passband bandwidth, and improve the performance of stopband rejection. Through the bending of microstrip line between the input and output parts, it is conducive to the physical access of isolation resistance, and the isolation performance between output ports is improved. The research results show that the central working frequency of the filtering power divider is 2.85 GHz (f 0). The 3 dB bandwidth width is 1.51 GHz, and the relative bandwidth is 52.9%. The out-of-band suppression is lower than −20 dB in the range of 3.96 to 11.1 GHz (3.89f 0), and the isolation between output ports is lower than −24.4 dB in the ultra-wideband range of DC to 12 GHz. The device has excellent application prospects in radio frequency communication systems, such as amplifiers and antenna arrays.","PeriodicalId":50542,"journal":{"name":"Electromagnetics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2022-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45423273","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-17DOI: 10.1080/02726343.2022.2161709
S. Kühn
ABSTRACT Aiming to bypass the Lorentz force, this study analyzes Maxwell’s equations from the perspective of a receiver at rest. This approach is necessary because experimental results suggest that the general validity of the Lorentz force might be questionable in non-stationary cases. Calculations in the receiver’s rest frame are complicated and, thus, are rarely performed. In particular, the most important case is missing: namely, the solution of a Hertzian dipole moving in the rest frame of the receiver. The present article addresses this knowledge gap. First, this work demonstrates how the inhomogeneous wave equation can be derived and generically solved in the rest frame of the receiver. Subsequently, the solution for two uniformly moving point charges is derived, and the close connection between Maxwell’s equations and Weber electrodynamics is highlighted. The gained insights are then applied to compute the far-field solution of a moving Hertzian dipole in the receiver’s rest frame. The resulting solution is analyzed, and an explanation is presented regarding why an invariant and symmetric wave equation is possible for Weber electrodynamics and why the invariance could be the consequence of a quantum effect.
{"title":"Inhomogeneous wave equation, Liénard-Wiechert potentials, and Hertzian dipoles in Weber electrodynamics","authors":"S. Kühn","doi":"10.1080/02726343.2022.2161709","DOIUrl":"https://doi.org/10.1080/02726343.2022.2161709","url":null,"abstract":"ABSTRACT Aiming to bypass the Lorentz force, this study analyzes Maxwell’s equations from the perspective of a receiver at rest. This approach is necessary because experimental results suggest that the general validity of the Lorentz force might be questionable in non-stationary cases. Calculations in the receiver’s rest frame are complicated and, thus, are rarely performed. In particular, the most important case is missing: namely, the solution of a Hertzian dipole moving in the rest frame of the receiver. The present article addresses this knowledge gap. First, this work demonstrates how the inhomogeneous wave equation can be derived and generically solved in the rest frame of the receiver. Subsequently, the solution for two uniformly moving point charges is derived, and the close connection between Maxwell’s equations and Weber electrodynamics is highlighted. The gained insights are then applied to compute the far-field solution of a moving Hertzian dipole in the receiver’s rest frame. The resulting solution is analyzed, and an explanation is presented regarding why an invariant and symmetric wave equation is possible for Weber electrodynamics and why the invariance could be the consequence of a quantum effect.","PeriodicalId":50542,"journal":{"name":"Electromagnetics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2022-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48518763","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-17DOI: 10.1080/02726343.2022.2161707
Baidenger Agyekum Twumasi, Jia‐lin Li, Ebenezer Tawiah Ashong, Christian Dzah, D. Pomary
ABSTRACT Motivated by the quest to curtail the high mortality rate of breast cancer, the manuscript proposes the sensitivity enhancement of monopole antenna for hyperthermia application by using electromagnetic time reversal (EMTR) technique with transformation structures for early treatment of multi-focal breast tumors. The EMTR technique is characterized with temporal and spatial focusing, hence enhancing the visibility of tumors embedded in the breast medium. In this study, we aim at the non-invasive power deposition on sub-wavelength-sized tumors at sub-wavelength separation incorporation with sub-wavelength scatterers. The paper is focused on enhancing the sensitivity of scattering reception in TR algorithm for hyperthermia application using sub-wavelength sized scatterers. The proposed applicator is an ultra-wideband (UWB) monopole antenna designed with sub-wavelength-sized split ring embedded square patch (SRESP) on a grounded substrate placed below it at some distance to serve as near field scatterer. Another plate of sub-wavelength scatterers but without the ground plate is placed in close proximity to the unhealthy breast in-conjunction with four ultra-wideband antenna time reversal mirrors (UWB-TRM). The proposed method shows promising potential for the selective power deposition for hyperthermia of sub-wavelength-sized tumors at sub-wavelength separations. This technique of enhancing front-end sensor sensitivity can also be extended to other optimization techniques for selective power deposition in hyperthermia of breast cancer.
{"title":"Time reversal mirror for hyperthermia of multi-focal breast tumors using electromagnetic time reversal technique","authors":"Baidenger Agyekum Twumasi, Jia‐lin Li, Ebenezer Tawiah Ashong, Christian Dzah, D. Pomary","doi":"10.1080/02726343.2022.2161707","DOIUrl":"https://doi.org/10.1080/02726343.2022.2161707","url":null,"abstract":"ABSTRACT Motivated by the quest to curtail the high mortality rate of breast cancer, the manuscript proposes the sensitivity enhancement of monopole antenna for hyperthermia application by using electromagnetic time reversal (EMTR) technique with transformation structures for early treatment of multi-focal breast tumors. The EMTR technique is characterized with temporal and spatial focusing, hence enhancing the visibility of tumors embedded in the breast medium. In this study, we aim at the non-invasive power deposition on sub-wavelength-sized tumors at sub-wavelength separation incorporation with sub-wavelength scatterers. The paper is focused on enhancing the sensitivity of scattering reception in TR algorithm for hyperthermia application using sub-wavelength sized scatterers. The proposed applicator is an ultra-wideband (UWB) monopole antenna designed with sub-wavelength-sized split ring embedded square patch (SRESP) on a grounded substrate placed below it at some distance to serve as near field scatterer. Another plate of sub-wavelength scatterers but without the ground plate is placed in close proximity to the unhealthy breast in-conjunction with four ultra-wideband antenna time reversal mirrors (UWB-TRM). The proposed method shows promising potential for the selective power deposition for hyperthermia of sub-wavelength-sized tumors at sub-wavelength separations. This technique of enhancing front-end sensor sensitivity can also be extended to other optimization techniques for selective power deposition in hyperthermia of breast cancer.","PeriodicalId":50542,"journal":{"name":"Electromagnetics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2022-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46582255","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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