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  Subjects -> ELECTRONICS (Total: 207 journals)
Showing 1 - 200 of 277 Journals sorted by number of followers
IEEE Transactions on Aerospace and Electronic Systems     Hybrid Journal   (Followers: 313)
Control Systems     Hybrid Journal   (Followers: 253)
IEEE Transactions on Geoscience and Remote Sensing     Hybrid Journal   (Followers: 201)
Journal of Guidance, Control, and Dynamics     Hybrid Journal   (Followers: 197)
Electronics     Open Access   (Followers: 138)
Advances in Electronics     Open Access   (Followers: 133)
Electronic Design     Partially Free   (Followers: 129)
Electronics For You     Partially Free   (Followers: 128)
IEEE Antennas and Propagation Magazine     Hybrid Journal   (Followers: 120)
IEEE Power Electronics Magazine     Full-text available via subscription   (Followers: 91)
IEEE Transactions on Power Electronics     Hybrid Journal   (Followers: 89)
IEEE Antennas and Wireless Propagation Letters     Hybrid Journal   (Followers: 88)
IEEE Transactions on Software Engineering     Hybrid Journal   (Followers: 84)
IEEE Transactions on Industrial Electronics     Hybrid Journal   (Followers: 84)
IEEE Transactions on Antennas and Propagation     Full-text available via subscription   (Followers: 81)
IET Power Electronics     Open Access   (Followers: 70)
IEEE Transactions on Automatic Control     Hybrid Journal   (Followers: 67)
Selected Topics in Applied Earth Observations and Remote Sensing, IEEE Journal of     Hybrid Journal   (Followers: 63)
IEEE Embedded Systems Letters     Hybrid Journal   (Followers: 62)
IEEE Transactions on Industry Applications     Hybrid Journal   (Followers: 58)
IEEE Journal of Emerging and Selected Topics in Power Electronics     Hybrid Journal   (Followers: 53)
Canadian Journal of Remote Sensing     Full-text available via subscription   (Followers: 53)
Advances in Power Electronics     Open Access   (Followers: 49)
IEEE Nanotechnology Magazine     Hybrid Journal   (Followers: 45)
IEEE Transactions on Consumer Electronics     Hybrid Journal   (Followers: 45)
Journal of Electrical and Electronics Engineering Research     Open Access   (Followers: 41)
IEEE Transactions on Biomedical Engineering     Hybrid Journal   (Followers: 35)
IEEE Transactions on Circuits and Systems for Video Technology     Hybrid Journal   (Followers: 34)
IET Microwaves, Antennas & Propagation     Open Access   (Followers: 34)
Journal of Physics B: Atomic, Molecular and Optical Physics     Hybrid Journal   (Followers: 32)
American Journal of Electrical and Electronic Engineering     Open Access   (Followers: 30)
IEEE Transactions on Information Theory     Hybrid Journal   (Followers: 28)
Electronics Letters     Open Access   (Followers: 28)
Bell Labs Technical Journal     Hybrid Journal   (Followers: 27)
Microelectronics and Solid State Electronics     Open Access   (Followers: 27)
International Journal of Power Electronics     Hybrid Journal   (Followers: 24)
International Journal of Aerospace Innovations     Full-text available via subscription   (Followers: 24)
Journal of Sensors     Open Access   (Followers: 23)
International Journal of Image, Graphics and Signal Processing     Open Access   (Followers: 22)
IEEE Reviews in Biomedical Engineering     Hybrid Journal   (Followers: 20)
IEEE/OSA Journal of Optical Communications and Networking     Hybrid Journal   (Followers: 19)
IEEE Transactions on Electron Devices     Hybrid Journal   (Followers: 18)
Journal of Artificial Intelligence     Open Access   (Followers: 18)
Journal of Power Electronics & Power Systems     Full-text available via subscription   (Followers: 17)
IET Wireless Sensor Systems     Open Access   (Followers: 17)
Circuits and Systems     Open Access   (Followers: 16)
Archives of Electrical Engineering     Open Access   (Followers: 15)
International Journal of Control     Hybrid Journal   (Followers: 14)
IEEE Transactions on Signal and Information Processing over Networks     Hybrid Journal   (Followers: 14)
International Journal of Advanced Research in Computer Science and Electronics Engineering     Open Access   (Followers: 14)
IEEE Women in Engineering Magazine     Hybrid Journal   (Followers: 13)
Advances in Microelectronic Engineering     Open Access   (Followers: 13)
IEEE Solid-State Circuits Magazine     Hybrid Journal   (Followers: 13)
Machine Learning with Applications     Full-text available via subscription   (Followers: 12)
Intelligent Transportation Systems Magazine, IEEE     Full-text available via subscription   (Followers: 12)
IEEE Transactions on Broadcasting     Hybrid Journal   (Followers: 12)
IEEE Transactions on Learning Technologies     Full-text available via subscription   (Followers: 12)
IEICE - Transactions on Electronics     Full-text available via subscription   (Followers: 11)
International Journal of Sensors, Wireless Communications and Control     Hybrid Journal   (Followers: 11)
International Journal of Microwave and Wireless Technologies     Hybrid Journal   (Followers: 11)
International Journal of Advanced Electronics and Communication Systems     Open Access   (Followers: 11)
Journal of Low Power Electronics     Full-text available via subscription   (Followers: 11)
Open Journal of Antennas and Propagation     Open Access   (Followers: 10)
Solid-State Electronics     Hybrid Journal   (Followers: 10)
International Journal of Advances in Telecommunications, Electrotechnics, Signals and Systems     Open Access   (Followers: 10)
IETE Journal of Research     Open Access   (Followers: 10)
Batteries     Open Access   (Followers: 9)
Electronics and Communications in Japan     Hybrid Journal   (Followers: 9)
International Journal of Wireless and Microwave Technologies     Open Access   (Followers: 9)
IETE Technical Review     Open Access   (Followers: 9)
Nature Electronics     Hybrid Journal   (Followers: 9)
Journal of Signal and Information Processing     Open Access   (Followers: 9)
APSIPA Transactions on Signal and Information Processing     Open Access   (Followers: 8)
IEEE Journal of the Electron Devices Society     Open Access   (Followers: 8)
International Journal of Electronics and Telecommunications     Open Access   (Followers: 8)
Journal of Electromagnetic Waves and Applications     Hybrid Journal   (Followers: 8)
China Communications     Full-text available via subscription   (Followers: 8)
Superconductivity     Full-text available via subscription   (Followers: 8)
IEEE Transactions on Autonomous Mental Development     Hybrid Journal   (Followers: 8)
Journal of Low Power Electronics and Applications     Open Access   (Followers: 8)
International Journal of Antennas and Propagation     Open Access   (Followers: 8)
Journal of Electronic Design Technology     Full-text available via subscription   (Followers: 8)
Advances in Electrical and Electronic Engineering     Open Access   (Followers: 8)
Universal Journal of Electrical and Electronic Engineering     Open Access   (Followers: 7)
Power Electronic Devices and Components     Open Access   (Followers: 7)
Foundations and Trends® in Signal Processing     Full-text available via subscription   (Followers: 7)
Nanotechnology, Science and Applications     Open Access   (Followers: 7)
IEEE Magnetics Letters     Hybrid Journal   (Followers: 7)
Progress in Quantum Electronics     Full-text available via subscription   (Followers: 7)
Foundations and Trends® in Communications and Information Theory     Full-text available via subscription   (Followers: 6)
Metrology and Measurement Systems     Open Access   (Followers: 6)
Advances in Biosensors and Bioelectronics     Open Access   (Followers: 6)
International Journal of Systems, Control and Communications     Hybrid Journal   (Followers: 6)
Kinetik : Game Technology, Information System, Computer Network, Computing, Electronics, and Control     Open Access   (Followers: 6)
International Journal of Electronics     Hybrid Journal   (Followers: 6)
IEICE - Transactions on Information and Systems     Full-text available via subscription   (Followers: 6)
Research & Reviews : Journal of Embedded System & Applications     Full-text available via subscription   (Followers: 6)
Journal of Power Electronics     Hybrid Journal   (Followers: 6)
Annals of Telecommunications     Hybrid Journal   (Followers: 6)
Electronic Markets     Hybrid Journal   (Followers: 6)
Energy Storage Materials     Full-text available via subscription   (Followers: 6)
IEEE Transactions on Services Computing     Hybrid Journal   (Followers: 5)
International Journal of Computational Vision and Robotics     Hybrid Journal   (Followers: 5)
Journal of Optoelectronics Engineering     Open Access   (Followers: 5)
Journal of Electromagnetic Analysis and Applications     Open Access   (Followers: 5)
Journal of Field Robotics     Hybrid Journal   (Followers: 5)
Journal of Electronics (China)     Hybrid Journal   (Followers: 5)
Batteries & Supercaps     Hybrid Journal   (Followers: 5)
IEEE Pulse     Hybrid Journal   (Followers: 5)
Journal of Microelectronics and Electronic Packaging     Hybrid Journal   (Followers: 4)
Networks: an International Journal     Hybrid Journal   (Followers: 4)
EPE Journal : European Power Electronics and Drives     Hybrid Journal   (Followers: 4)
Advanced Materials Technologies     Hybrid Journal   (Followers: 4)
Frontiers in Electronics     Open Access   (Followers: 4)
Wireless and Mobile Technologies     Open Access   (Followers: 4)
Synthesis Lectures on Power Electronics     Full-text available via subscription   (Followers: 4)
Journal of Energy Storage     Full-text available via subscription   (Followers: 4)
IEEE Transactions on Haptics     Hybrid Journal   (Followers: 4)
Journal of Electrical Engineering & Electronic Technology     Hybrid Journal   (Followers: 4)
Journal of Circuits, Systems, and Computers     Hybrid Journal   (Followers: 4)
International Journal of Review in Electronics & Communication Engineering     Open Access   (Followers: 4)
Electronic Materials Letters     Hybrid Journal   (Followers: 4)
Journal of Biosensors & Bioelectronics     Open Access   (Followers: 4)
Biomedical Instrumentation & Technology     Hybrid Journal   (Followers: 4)
IJEIS (Indonesian Journal of Electronics and Instrumentation Systems)     Open Access   (Followers: 3)
Informatik-Spektrum     Hybrid Journal   (Followers: 3)
IEEE Journal on Exploratory Solid-State Computational Devices and Circuits     Hybrid Journal   (Followers: 3)
International Journal of Numerical Modelling: Electronic Networks, Devices and Fields     Hybrid Journal   (Followers: 3)
Advancing Microelectronics     Hybrid Journal   (Followers: 3)
International Journal of Applied Electronics in Physics & Robotics     Open Access   (Followers: 3)
IETE Journal of Education     Open Access   (Followers: 3)
Superconductor Science and Technology     Hybrid Journal   (Followers: 3)
Sensors International     Open Access   (Followers: 3)
e-Prime : Advances in Electrical Engineering, Electronics and Energy     Open Access   (Followers: 3)
EPJ Quantum Technology     Open Access   (Followers: 3)
Frontiers of Optoelectronics     Hybrid Journal   (Followers: 3)
Transactions on Electrical and Electronic Materials     Hybrid Journal   (Followers: 2)
ACS Applied Electronic Materials     Open Access   (Followers: 2)
IET Smart Grid     Open Access   (Followers: 2)
Energy Storage     Hybrid Journal   (Followers: 2)
Journal of Microwave Power and Electromagnetic Energy     Hybrid Journal   (Followers: 2)
Australian Journal of Electrical and Electronics Engineering     Hybrid Journal   (Followers: 2)
Journal of Information and Telecommunication     Open Access   (Followers: 2)
TELKOMNIKA (Telecommunication, Computing, Electronics and Control)     Open Access   (Followers: 2)
Journal of Semiconductors     Full-text available via subscription   (Followers: 2)
Radiophysics and Quantum Electronics     Hybrid Journal   (Followers: 2)
International Transaction of Electrical and Computer Engineers System     Open Access   (Followers: 2)
Journal of Intelligent Procedures in Electrical Technology     Open Access   (Followers: 2)
Sensing and Imaging : An International Journal     Hybrid Journal   (Followers: 2)
Security and Communication Networks     Hybrid Journal   (Followers: 2)
Journal of Nuclear Cardiology     Hybrid Journal   (Followers: 2)
ECTI Transactions on Electrical Engineering, Electronics, and Communications     Open Access   (Followers: 1)
IET Energy Systems Integration     Open Access   (Followers: 1)
Majalah Ilmiah Teknologi Elektro : Journal of Electrical Technology     Open Access   (Followers: 1)
International Journal of Granular Computing, Rough Sets and Intelligent Systems     Hybrid Journal   (Followers: 1)
IEEE Letters on Electromagnetic Compatibility Practice and Applications     Hybrid Journal   (Followers: 1)
Journal of Computational Intelligence and Electronic Systems     Full-text available via subscription   (Followers: 1)
Електротехніка і Електромеханіка     Open Access   (Followers: 1)
Open Electrical & Electronic Engineering Journal     Open Access   (Followers: 1)
IEEE Journal of Electromagnetics, RF and Microwaves in Medicine and Biology     Hybrid Journal   (Followers: 1)
Journal of Advanced Dielectrics     Open Access   (Followers: 1)
Transactions on Cryptographic Hardware and Embedded Systems     Open Access   (Followers: 1)
International Journal of Hybrid Intelligence     Hybrid Journal   (Followers: 1)
Ural Radio Engineering Journal     Open Access   (Followers: 1)
IET Cyber-Physical Systems : Theory & Applications     Open Access   (Followers: 1)
Edu Elektrika Journal     Open Access   (Followers: 1)
Power Electronics and Drives     Open Access   (Followers: 1)
Automatika : Journal for Control, Measurement, Electronics, Computing and Communications     Open Access  
npj Flexible Electronics     Open Access  
Elektronika ir Elektortechnika     Open Access  
Emitor : Jurnal Teknik Elektro     Open Access  
IEEE Solid-State Circuits Letters     Hybrid Journal  
IEEE Open Journal of Industry Applications     Open Access  
IEEE Open Journal of the Industrial Electronics Society     Open Access  
IEEE Open Journal of Circuits and Systems     Open Access  
Journal of Electronic Science and Technology     Open Access  
Solid State Electronics Letters     Open Access  
Industrial Technology Research Journal Phranakhon Rajabhat University     Open Access  
Journal of Engineered Fibers and Fabrics     Open Access  
Jurnal Teknologi Elektro     Open Access  
IET Nanodielectrics     Open Access  
Elkha : Jurnal Teknik Elektro     Open Access  
JAREE (Journal on Advanced Research in Electrical Engineering)     Open Access  
Jurnal Teknik Elektro     Open Access  
IACR Transactions on Symmetric Cryptology     Open Access  
Acta Electronica Malaysia     Open Access  
Bioelectronics in Medicine     Hybrid Journal  
Chinese Journal of Electronics     Open Access  
Problemy Peredachi Informatsii     Full-text available via subscription  
Technical Report Electronics and Computer Engineering     Open Access  
Jurnal Rekayasa Elektrika     Open Access  
Facta Universitatis, Series : Electronics and Energetics     Open Access  
Visión Electrónica : algo más que un estado sólido     Open Access  
Telematique     Open Access  
International Journal of Nanoscience     Hybrid Journal  
International Journal of High Speed Electronics and Systems     Hybrid Journal  
Semiconductors and Semimetals     Full-text available via subscription  

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Similar Journals
Journal Cover
IEEE Antennas and Wireless Propagation Letters
Journal Prestige (SJR): 1.047
Citation Impact (citeScore): 4
Number of Followers: 88  
 
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
ISSN (Print) 1536-1225
Published by IEEE Homepage  [228 journals]
  • IEEE Antennas and Wireless Propagation Letters Publication Information

    • Free pre-print version: Loading...

      Abstract: Presents a listing of the editorial board, board of governors, current staff, committee members, and/or society editors for this issue of the publication.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • Design of Thermal-Switchable Absorbing Metasurface Based on Vanadium
           Dioxide

    • Free pre-print version: Loading...

      Authors: Zhongbao Wang;Qiang Chen;Yanli Ma;Tiantian Guo;Chenyang Shuai;Yunqi Fu;
      Pages: 2302 - 2306
      Abstract: This letter presents a thermal-switchable absorbing metasurface (TSAM) based on the phase-change material vanadium dioxide (VO2). A thin film of VO2 was deposited on a sapphire substrate by a magnetron sputtering and then sliced into tiny chips, which can be regarded as thermal-switchable resistors. The surface structure of the TSAM element is realized by loading four VO2 chips into a square metallic loop. Polytetrafluoroethylene is used as the substrate due to its high thermal conductivity compared with foam. The TSAM is on the “absorbing” mode when it is heated underneath and is switched into the “reflecting” mode at room temperature. The absorbing mode is characterized by a wideband absorption (8–22 GHz). A TSAM prototype was fabricated and measured to verify this design.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • Mutual Coupling and Impedance of a VLF Curtain Array in an Anisotropic
           Magnetoplasma

    • Free pre-print version: Loading...

      Authors: Tong He;Xue Wei Zhang;Hui Ran Zeng;Kai Li;
      Pages: 2307 - 2311
      Abstract: In this letter, we investigate and propose an analytical method for calculating the mutual impedance of a very low frequency (VLF: 3–30 kHz) curtain array immersed in an anisotropic magnetoplasma. The $N$ simultaneous integral equations satisfied by the array are first built with full consideration of the coupling effect between different elements. Under the assumption that the currents of adjacent elements differ from a fixed phase, the $N$-coupled integral equations are reduced to an independent one, which is solved to determine the complete distribution of current on each element. The self- and mutual impedances of the array are then evaluated through the induced electromotive force method. Computations show that the current is more concentrated at the middle part of the antenna as its electrical length increases, and the error that appeared on both the amplitude and phase of the required voltages verifies the existence of the mutual coupling effect. It is also found that both the self- and mutual impedances will experience certain fluctuations when the electrical length of the elements changes, with maxima and minima occurring at several particular lengths. The approach may provide theoretical support to the prediction of mutual impedance in practical VLF array applications.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • A Model for Calculating Electromagnetic Scattering From Target in
           Evaporation Duct

    • Free pre-print version: Loading...

      Authors: Yiwen Wei;Mengyan Gao;Dayong Tian;Lixin Guo;Juan Li;Lixia Yang;Xiangming Guo;
      Pages: 2312 - 2316
      Abstract: In this letter, we proposed a new model to solve the scattering problem from target in evaporation duct. First, the traditional two-dimensional (2-D) subsection ray tracing (SRT) method is extended to 3-D case. Then the 3D SRT is used to obtain the propagation direction and attenuation of the transmitted electromagnetic wave from antenna. Second, shooting and bouncing rays (SBR) is used in the simulation of complex target scattering. Different from traditional SBR, the launched rays are not planed wave. A virtual transmitting plane is established to obtain the amplitude and direction of these rays in evaporation duct in front of the target. The transmitting plane in evaporation duct can be regard as the incident field of SBR method. What's more, the new model based on SBR is accelerated by CUDA and OptiX from Nvidia to deal with the tremendous number of rays. Finally, the scattering EM field and power distributions in evaporation duct environment are calculated and discussed in the last section.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • A Wideband High-Gain LHCP/RHCP Patch Antenna Based on Mirror Feed
           Method

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      Authors: Chanfang Cao;Chen Guo;
      Pages: 2317 - 2321
      Abstract: This letter proposes a wideband high-gain left-/right-handed circularly polarized (L/RHCP) patch antenna using a mirror flip approach. The antenna consists of a ring-shaped metal square patch with truncated corners and a two-port feed network in a simple construction. The dual-port feed and truncated corners realize a wide axial ratio bandwidth (ARBW). Moreover, the L/RHCP is easily changed by mirroring the flipped feed network without redesigning the overall topology. The impedance bandwidth (IBW) (S11 < −10 dB) of 58.6% (2.97–5.43 GHz)/47.6% (2.8–4.55 GHz) and 3 dB ARBW of 44.3% (3.09–4.85 GHz)/34.6% (2.96–4.2 GHz) are achieved for L/RHCP antenna. Finally, two prototypes were fabricated and measured for validation. The proposed L/RHCP patch antenna was found to be insensitive to feed position. The IBWs of the proposed LHCP and RHCP antennas showed a wide degree of overlap. The low profile, high gain, small size, and higher robustness of our antenna than traditional patch antennas demonstrate the advantageous of our design for communication, power transmission, and medical fields.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • Low-Complexity Sparse Array Synthesis Based on Off-Grid Compressive
           Sensing

    • Free pre-print version: Loading...

      Authors: Songjie Yang;Baojuan Liu;Zhiqin Hong;Zhongpei Zhang;
      Pages: 2322 - 2326
      Abstract: In this letter, a novel sparse array synthesis method for nonuniform planar arrays is proposed, which belongs to compressive sensing (CS) based synthesis. Particularly, we propose an off-grid refinement technique to simultaneously optimize the antenna element positions and excitations with a low complexity, in response to the antenna position optimization problem that is difficult for standard CS. More importantly, we take into account the minimum interelement spacing constraint for ensuring the physically realizable solution. Specifically, the off-grid orthogonal match pursuit algorithm is first proposed with low complexity and then off-grid look ahead orthogonal match pursuit is designed with better synthesis performance but higher complexity. In addition, simulation results have shown that the proposed schemes have more advantages in computational complexity and synthesis performances compared with the related method.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • Polarization-Reconfigurable Compact Wideband Slot Antenna by Using Liquid
           Metal

    • Free pre-print version: Loading...

      Authors: Hongmei Liu;Tuanyuan Yan;ZiMeng Zhao;Zhongbao Wang;Shaojun Fang;
      Pages: 2327 - 2331
      Abstract: In this letter, a compact, low-profile, and wideband slot antenna with polarization reconfigurability is presented by using liquid metal (LM). A small rectangular ring placed below the microstrip line of a symmetric coplanar waveguide (CPW) is used for bandwidth enhancement. Three horizontal currents performed by LM injection are inserted for wide circular polarized excitation. The channel realized by three-dimensional printed technique is loaded on the antenna to provide reconfiguration conditions. By injecting the LM into the left or right channels, the radiation of right-hand circular polarization or left-hand circular polarization is achieved. While when the two channels are empty or both LM injections, the linear polarization (LP) radiations at two operating frequency bands are obtained. A prototype was fabricated and measured. Measurements show that the proposed antenna exhibits a wide impedance bandwidth (IBW) of 67% and an overlapped axial ratio bandwidth of 39.2% for the CP modes. While in the LP states, the overall reconfigurable IBW is 39.7%. Besides, the size of the antenna is 0.30 λ0 × 0.32 λ0 × 0.03 λ0, which is quite compact and low-profile.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • Implementation and MIMO Performance Assessment of Two Quad-Polarized
           Antennas

    • Free pre-print version: Loading...

      Authors: Yijue Wang;Dazhi Piao;Junping Song;
      Pages: 2332 - 2336
      Abstract: In this letter, two compact, colocated, low-coupled, quad-polarized (QP) antennas are proposed based on two dual-mode radiation bodies to achieve compactness and high isolation. The first antenna obtains four polarizations by orthogonally placing two dual-mode loops; the second antenna includes a dual-mode loop and a miniaturized dual-polarized patch based on fractal structures inside the loop. To investigate the performance of QP multiple-input–multiple-output (MIMO) systems, channel parameters including correlation coefficients, degree of power balance, and channel capacities are analyzed based on the measured data. Results show that, high channel capacities can be achieved both in a realistic office room and a rich scattered reverberation chamber, which are very close to that of the 4 × 4 independently identically distributed (i.i.d.) Rayleigh channel. It is revealed that both correlation coefficient and degree of received power balance have strong influence on the performance of a MIMO system, which are related to the radiation properties of the antenna and the polarimetric characteristics of the propagation environment.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • Surface Integral Equation With Multibranch RWG Basis Functions for
           Electromagnetic Scattering From Dielectric Objects

    • Free pre-print version: Loading...

      Authors: Ziwei Li;Xinlei Chen;Zhiwen Dong;Fan Gao;Bingzheng Xu;Changqing Gu;
      Pages: 2337 - 2341
      Abstract: A surface integral equation method with multibranch Rao–Wilton–Glisson (MB-RWG) basis functions for scattering from dielectric objects is proposed based on the electric and magnetic current combined field integral equations (JMCFIE). The MB-RWGs are defined at the boundaries between dense and coarse meshes and can keep the current continuity. Thus, the JMCFIE with MB-RWGs allows different surfaces of the dielectric models to be independently discretized by triangles with different sizes. Compared with the conventional JMCFIE, the JMCFIE with MB-RWGs increases the flexibility of mesh generation, which is attractive for multiscale dielectric models. Furthermore, the iterative convergence of JMCFIE with MB-RWGs is similar to that of conventional JMCFIE. Numerical examples are presented to demonstrate the advantages of the proposed method.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • A Filtering Antenna Using Transversal Coupling Topology

    • Free pre-print version: Loading...

      Authors: Jian-Feng Qian;Steven Gao;Hanyang Wang;Hai Zhou;Huiliang Xu;Lehu Wen;
      Pages: 2342 - 2346
      Abstract: In this letter, a coupling scheme for the realization of filtering antennas is introduced. This coupling scheme allows the filtering antenna to realize a filter-like reflection coefficient using an all-radiator structure. Instead of cascading resonators one by one in a ladder manner, in a transversal filtering antenna (TFA), all the radiative resonators are coupled to the source simultaneously. The impedance and radiation behaviors of these subantennas (SAs) can be designed individually. So, the performance of these filtering antennas has much lower sensitivity to their physical structure than conventional cascaded designs, which makes the design of such a filtering antenna much easier. Besides, this topology can realize out-of-band gain zeros without using any parasitic elements or cross-coupling structures. The locations of these gain zeros can be controlled by simply changing the lengths of each SA. To the authors’ knowledge, this is the first time that a transversal filtering antenna with all resonators radiative is presented. For validation, some transversal filtering antenna designs with different coupling topologies are introduced to prove the concept and show their advantages. A third-order prototype is fabricated and measured for demonstration, showing good agreement between the simulated and measured results.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • Stochastic Quantification of Array Antennas With Random Feeding Errors
           Using an Improved Polynomial Chaos Expansion Method

    • Free pre-print version: Loading...

      Authors: Quanfeng Wang;Yunru Zhao;Qi Wu;
      Pages: 2347 - 2351
      Abstract: Electromagnetic properties of an array antenna are inevitably affected by random magnitude and phase errors in the feeding network. Polynomial chaos expansion (PCE) method can analyze such problems, but the number of numerical quadrature grows rapidly with stochastic dimensionality for solving the PCE coefficients. An improved PCE algorithm is proposed to improve the computational efficiency. A large array is decomposed into several small groups those can be efficiently treated by the PCE method. Stochastic quantification of the whole array is achieved by the superposition of grouped results. In addition, the proposed method can integrate with the method of moments to treat real-world arrays. The results computed by this method agree with those of Monte Carlo, and the computational time is reduced by two orders of magnitude for a dipole array with 64 elements.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • Application of Dielectric-Artificial Magnetic Conductor Composite
           Substrate to Design Miniaturized P-Band Microstrip Antenna for Wireless
           Underground Sensor Network

    • Free pre-print version: Loading...

      Authors: Sarath Kumar Annavarapu;Abhijyoti Ghosh;L. Lolit Kumar Singh;Sudipta Chattopadhyay;Chow-Yen-Desmond Sim;
      Pages: 2352 - 2356
      Abstract: In the modern era of wireless Internet of Things designing a planar antenna at relatively low frequency (P-band) with positive gain and high efficiency is exacting task. In this letter, a planar P-band microstrip antenna (a simple rectangular patch of size 0.16λ0×0.20λ0×0.01λ0, smaller than classical quarter-wave patch) for wireless underground sensor network (WUSN) is proposed. The proposed structure yields high gain with the judicious use of four shorting vias, which are collocated along the side edges of the patch with a composite substrate (dielectric-artificial magnetic conductor). The results shows that the designed antenna resonates at 413 MHz with gain and efficiency of 3.1 dBi and 75%, respectively, with a 10 dB impedance bandwidth of 2% (408–416 MHz)
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • On the Validity of the Asymptotic Near-Ground Propagation Model of
           Hertzian Dipole for Finite-Length Dipole Antennas

    • Free pre-print version: Loading...

      Authors: Hocine Anis Belaid;Shermila Mostarshedi;Benoit Poussot;Jean-Marc Laheurte;
      Pages: 2357 - 2361
      Abstract: This letter deals with the near-ground propagation of electromagnetic waves, when the emitting antenna is a finite length dipole, rather than an elementary one. The existing propagation model for an elementary Hertzian dipole is extended to a realistic case by assuming a known current distribution over the finite-length dipole. Validation of the theoretical models by an electromagnetic simulator (NEC2d) is also presented in this article.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • 3-D Ray Launching MIMO Channel Geometric Estimation

    • Free pre-print version: Loading...

      Authors: Fidel Alejandro Rodríguez-Corbo;Leyre Azpilicueta;Mikel Celaya-Echarri;Raed Shubair;Francisco Falcone;
      Pages: 2362 - 2366
      Abstract: The complete multiple-input–multiple-output (MIMO) channel simulation in deterministic techniques can be a computationally intensive task, due to the inherent scenario's complexity and number of antennas. The spatial coherence among MIMO elements is a reasonable assumption to approximate the channel from a single point simulation. In this letter, a novel method to incorporate a geometrical approximation of the MIMO channel into a three-dimensional ray launching (3D-RL) algorithm is presented. The method is antenna type independent and the orientation of the array is embedded in the antenna representation. Relevant information of the MIMO channel characteristics like the root mean square (rms) delay spread, the maximum delay spread, phase and channel capacity are obtained and compared with the full 3D-RL simulation of the entire MIMO array, achieving 93.4% reduction in computational time.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • Low-Profile Dual-Wideband Dual-Polarized Antenna for 5G Millimeter-Wave
           Communications

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      Authors: Sheng Jie Yang;Shu Feng Yao;Ru-Yu Ma;Xiu Yin Zhang;
      Pages: 2367 - 2371
      Abstract: This letter presents a dual-wideband dual-polarized antenna that fully covers the fifth-generation (5G) millimeter-wave (mm-wave) bands of n257−n261 (24.25–29.5 GHz and 37–43.5 GHz), and that shows a low-profile feature and a band-stop filtering response. For each polarization, the low-band and high-band radiation modes are, respectively, achieved by the two pairs of U-shaped dipole arms which are distributed along the co- and cross-polarized directions. Meanwhile, a radiation null is generated by the radiating cancellation effect of the two pairs of dipole arms, suppressing the unwanted frequency between the two operating bands. Moreover, an extra high-band resonant mode is introduced by the parasitic patches, enhancing the bandwidth of the proposed antenna. Furthermore, a vertical balun structure connecting each dipole arm with the ground is bent to reduce the antenna profile. In the fabrication, high-density interconnect printed circuit board process is employed to meet the antenna-in-package consideration. Under the constrained substrate thickness of 1 mm, the proposed antenna achieves a dual-wideband operation of 24–30 GHz (22%) and 37–43.5 GHz (16%). These merits make the proposed antenna suitable for 5G mm-wave communications.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • A Nonuniform Compressed High-Order Mode Dipole With Sidelobe Suppression

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      Authors: Yu Luo;Ni Zhang;Zhi Ning Chen;Wenxing An;Kaixue Ma;Qing-Xin Chu;
      Pages: 2372 - 2376
      Abstract: A nonuniform compressed high-order mode dipole with suppressed sidelobe is proposed and investigated. The main performance characteristics, such as directivity, sidelobe, and radiation resistance of a third-order mode dipole with two independent compression coefficients are fully investigated. The investigation shows that enhanced directivity, suppressed sidelobe, and high radiation resistance are achieved simultaneously by selecting the appropriate compression coefficients. The compressed converse current leads to the sidelobe suppression. To verify the investigation, a third-order mode dipole antenna with nonuniform compression is designed, fabricated, and measured. The measurement shows that the reflection coefficient is less than −10 dB over the band of 2.46–2.65 GHz (one of the sub-6 GHz bands of fifth generation). The achieved gain is 4.7 dBi. The sidelobe level is less than −15.4 dB, 9.4 dB lower than the uniform compressed third-order mode dipoles.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • Dual Circularly Polarized Broadband Antenna Array for Millimeter-Wave
           Applications

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      Authors: Yang Cheng;Yuandan Dong;
      Pages: 2377 - 2381
      Abstract: A planar dual circularly polarized (CP) broadband array is proposed in this letter. The antenna consists of two semicircular patches and two suspended metal posts. According to the investigation of our previous work, the circularly polarized mode generated by combining the patches and the metal posts can achieve very wideband CP radiation. In order to achieve dual CP radiation with similar performance, a new antenna element is proposed with a centrally symmetrical configuration. The orthogonally crossed slot etched on the substrate-integrated waveguide cavity is used to excite the antenna element. A 4×4 array is designed, fabricated, and tested. Measured results show that a 3 dB AR bandwidth of 28.28% (26–34.6 GHz) and 30.61% (26–35.4GHz) is achieved for left-handed CP (LHCP) and right-handed CP (RHCP) radiation, respectively. The 3 dB gain bandwidth of 22.81% (26.4–33.2 GHz) and 24.50% (26–33.26 GHz) for these two polarizations is obtained. The proposed array demonstrates the feasibility of dual-polarized radiation. It features the advantage of wide bandwidth, easy integration, and low cost, which is very suitable for millimeter-Wave system applications.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • Hybrid Power Harvesting From Ambient Radiofrequency and Solar Energy

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      Authors: Yan Shi;Ying Hong Nan;
      Pages: 2382 - 2386
      Abstract: In this letter, a power harvester with a Schottky diode and a photodiode has been designed to harvest ambient radiofrequency (RF) and solar power in a cooperative way. The RF power is collected by a coplanar waveguide-fed circularly polarized antenna operating in wifi band and converted into the dc one by a rectifying circuit composed of the Schottky diode, and meanwhile the solar energy is harvested by the photodiode to bias the Schottky diode in the rectifying circuit. With the RF and solar power simultaneously injecting into the rectifying circuit, the resulting power conversion efficiency is greatly increased for the same RF and solar power levels in a range from −20 to 0 dBm. The prototype of the proposed harvester is fabricated, and the measured results demonstrate a maximal total PCE of 73% and a maximal output power of 1450 μW.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • A Colinearly Polarized Full-Duplex Antenna With Extremely High
           Tx–Rx Isolation

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      Authors: Jogesh Chandra Dash;Debdeep Sarkar;
      Pages: 2387 - 2391
      Abstract: In this letter, we present a colinearly polarized in-band full-duplex (FD) microstrip antenna system with passive self-interference cancelation achieved from extremely high interport isolation. The proposed FD antenna achieves this isolation enhancement without the use of any circulator, hybrid or complex feed-network, by adopting a novel combination of: 1) field-confinement near individual antennas due to metallic vias, and 2) U-shaped slots etched from the ground plane. The proposed FD antenna demonstrates interport isolation values of $>!!54$ dB over the operating band of 5850–5945 MHz (IEEE 802.11p band for V2X-ITS) and $approx !!90$ dB at 5.9 GHz, along with broadside gain of 5.63 dBi and X-pol level less than 20 dB. The design procedure of the proposed planar FD antenna is explained and verified by CST-MWS full-wave simulations along with experimental results on fabricated antenna prototype.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • Design of an Anisotropic Reconfigurable Reflective Polarization Converter
           for Realizing Circular Polarization-Reconfigurable Antenna

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      Authors: Ankit Bhattacharjee;Santanu Dwari;
      Pages: 2392 - 2396
      Abstract: A polarization-reconfigurable antenna is presented here with the help of an anisotropic reconfigurable reflective polarization converter (RRPC). Proposed design consists of a monopole antenna as a source and an electronically switchable polarizer. Depending on the conducting states of only eight PIN diodes, which are placed on the top surface of the polarizer, linearly polarized (LP) wave generated by the monopole can be converted into left-hand circularly polarized (LHCP), right-hand circularly polarized (RHCP), and LP wave. Proposed RRPC has a ground plane on the back side and it is positioned below the source antenna with an air gap of 0.13 λ0 where λ is calculated at the antenna's operating frequency of 3.5 GHz. Overall configuration of the antenna is compact with a dimension of (0.31×0.31×0.19) λ03. As fewer active elements are used in the proposed design, complexity of the circuit for biasing and losses would be less. To the best of authors’ knowledge, it is first time reported work on active reflective polarizer, which not only has LP-to-CP polarization conversion ability but also it possesses electronic polarization switching ability in between LHCP, RHCP, and LP states.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • Double-Layer Microstrip Antenna Integrated With Solar Cells

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      Authors: Wenxing An;Tian Gong;Yu Luo;Jian Wang;
      Pages: 2397 - 2401
      Abstract: A low-profile broadband double-layer microstrip antenna is presented for green mobile communications. Eight solar cells are adopted for the top radiation structure, which can also improve the antenna performance. The antenna height is 0.071 λ0 (λ0 is the wavelength of 2.2 GHz in free space) with a measured −10 dB bandwidth from 1.65–2.76 GHz, so the mobile communication band from 1.71 to 2.69 GHz has been covered. Boresight radiation patterns are realized with an average gain of 8.27 dBi and measured radiation efficiency of more than 80% within the target band. This dual-function device can be a competitive candidate for green low-carbon communication systems.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • A Half-Mode Groove Gap Waveguide for Single-Layer Antennas in the
           Millimeter-Wave Band

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      Authors: Miguel Ferrando-Rocher;Jose Ignacio Herranz-Herruzo;Alejandro Valero-Nogueira;Mariano Baquero-Escudero;
      Pages: 2402 - 2406
      Abstract: This letter presents an alternative to significantly reduce the time and difficulty in designing and fabricating antennas in gap waveguide (GW) technology by using a novel half-mode groove GW. GW is often criticized within the subtractive manufacturing field for the high fabrication time required to mill many pins with the waveguides in the same piece. To demonstrate the possibilities of this new approach, two different antennas have been designed, fabricated, and measured. Both antennas, formed by only two pieces with no contact, operate from 29 to 31 GHz and present reflection coefficients below $-$10 dB and high antenna efficiency above 90$%$. In addition, both prototypes can reuse the bed of nails, which favors shorter manufacturing times and lower costs in the development phase.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • Modeling of Diurnal Variation Characteristics of VLF Wave Propagation in
           Earth-Ionosphere Waveguide With FDTD Method

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      Authors: Yurong Pu;Ting Lv;Jiangfan Liu;Xiaoli Xi;
      Pages: 2407 - 2411
      Abstract: In this letter, Wait's exponential (EXP) model and international reference ionosphere (IRI) model are combined to study the diurnal variation characteristics of very low frequency (VLF) wave propagation. The EXP model is used below the IRI model to compensate for the subionosphere electron density lack of the IRI. The major EXP parameters are reconstructed from the lower IRI electron density for different times of the day. Being capable of characterizing the subionosphere details, the combined IRIEXP model gets higher accuracy than the pure IRI model for VLF diurnal variation prediction. The measurement result is replicated by using the finite-difference time-domain method to validate the presented model.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • Optically Transparent Ultrawideband Electromagnetic Stealth Metasurface
           for Microwave Absorption and Scattering

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      Authors: Yuzhou Ran;Lihua Shi;Shuran Wu;Jie Li;Xin Jin;Zhenwei Hou;Bo Fan;Jianbao Wang;
      Pages: 2412 - 2416
      Abstract: For the issue of stealth and electromagnetic protection of weapons and equipment in strong electromagnetic pulse (EMP) environment, a transparent double-sided ultrawideband metasurface is proposed to realize wave absorption/absorption-scattering integrated function in two directions. The interactions between backscattered waves produced by the meta-atoms are manipulated and optimized simultaneously by hybrid far-field scattering pattern analysis and genetic algorithm to achieve ultra wideband destructive interference. Both simulation and experimental results demonstrate that the polarization-independent −10 dB radar cross section (RCS) reduction performance can be achieved for more than 128% of the fractional bandwidth (4–18.25 GHz) at forward incidence, and the absorption more than 90% in the range of 2.75–12.75 GHz (fractional bandwidth more than 129%) at backward incidence. The scattering and absorbing characteristics of the metasurface are still well maintained in the range of 0°–50° oblique incidence. The method of this letter has an important prospect in related applications of strong EMP stealth and protection technology under the integration of information equipment in the future.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • Broadband Low-RCS Circularly Polarized Antenna Realized by Nonuniform
           Metasurface

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      Authors: Xi Gao;Sijie Yin;Guofu Wang;Chunhua Xue;Xianming Xie;
      Pages: 2417 - 2421
      Abstract: A broadband circularly polarized metasurface antenna with low radar cross section (RCS) is proposed. Four metasurface elements are arranged orthogonally in a 2×2 array and fed with a 90° phase difference to achieve circular polarization radiation. Each metasurface element is a nonuniform subarray of 4×4 metallic patches. Attributed to the nonuniform property of the metasurface element, two characteristic modes with different resonant frequencies but with similar surface current distributions are formed. By optimizing the geometric parameters of the nonuniform element, the two modes are merged with each other, resulting in bandwidth (BW) broadening of the proposed antenna. Simulated and measured results show that the designed antenna has a −10 dB impedance BW of 49.60%, 3 dB axial ratio BW of 33.13%, and peak gain of 13.17 dBic. Moreover, the RCS reduction is higher than 6 dB in the entire operation frequency band. Additionally, the antenna has a low profile of 0.08λ (λ is the free-space wavelength at an operation frequency of 8.25 GHz).
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • Broadband Low-Profile Frequency Selective Rasorber Using Ultraminiaturized
           Metal-Graphene Structure

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      Authors: Bian Wu;Ding Zhang;Biao Chen;Yao-Jia Yang;Yu-Tong Zhao;Tao Su;
      Pages: 2422 - 2426
      Abstract: In this letter, a broadband and low-profile frequency selective rasorber with an ultraminiaturized metal-graphene structure is proposed. The rasorber is composed of two cascaded layers separated by an air spacer, a top lossy layer and a bottom bandpass layer. By supplying four branches of multiple vias connected stubs across a circular graphene film in the lossy layer, extra inductance and capacitance effects are introduced while guaranteeing the impedance match with the free space at the low frequency range. As a result, a broad absorption bandwidth is ensured from 1.96 to 10.2 GHz with the thickness of only 0.076 λl at the lowest absorption frequency, and the passband is at 12.83 GHz with the insertion loss of 0.23 dB. Besides, a miniaturized unit is achieved with the period of 0.039 λl, and the oblique angle incidence response is up to 45° for TE and TM modes. To validate the design, a prototype is fabricated and measured, and the screen-printing process of graphene resistive film as omnidirectional resistance is adopted to further reduce the profile. The measured results agree well with the simulation.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • RCS Calculation of Electrically Large Targets by Iterative Bidirectionally
           Ray Tracing Method

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      Authors: Zhou Cong;Zi He;Da-Zhi Ding;
      Pages: 2427 - 2431
      Abstract: An efficient electromagnetic (EM) scattering solution of iterative bidirectionally ray tracing method has been proved to analyze the scattering from electrically large bodies with multiple reflection structures. The algorithm starts by building a bidirectionally ray tracing in both incident and backward observed directions. More specifically, both the multiple geometric optical reflections and physical optical scatterings are taken into consideration during the process of ray tracing. Meanwhile, the selected current interactions are iterative accounted so as to obtain the reradiation effect for the multiple reflections. On this bases, the reradiation effect supplements the mechanism of the nonspecular scattering obtained on side lobe directions and achieves higher accuracy than the ray tracing-based method. After that, the target-coupled edge diffraction theory is used to modify the target scattering field to obtain valuable RCS results. The EM scatterings from complex structures are simulated to verify the performance of the proposed method.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • A Flexible Planarized Biconical Antenna for Partial Discharge Detection in
           Gas-Insulated Switchgear

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      Authors: Guozhi Zhang;Jinwen Tian;Xiaoxing Zhang;Jianben Liu;Changyue Lu;
      Pages: 2432 - 2436
      Abstract: This letter proposes a new ultrahigh frequency (UHF) flexible planar biconical antenna design method for partial discharge (PD) detection in gas-insulated switchgear. Continuous transverse branching increases the electrical length to expand the bandwidth and miniaturize the antenna. For comparison of the effects of the lateral branch structure model, the optimized dimensions of both designed antennas are 150×150 mm, and both use polydimethylsiloxane, flexible material with a thickness of 0.5 mm, as the substrate. The results show that the S11 of the antennas is less than −10 dB in the bands of 0.3–0.5, 0.64–1.25, and 1.4–3.0 GHz, and the planar biconical antennas still maintain good bandwidth and gain under different bending radii of 0, 150, 350, and 500 mm. The PD test platform was built to test the antenna. The experimental data show that the two flexible antennas designed in this letter can detect the PD-radiated electromagnetic wave signal with a discharge of 15 pc before and after the bending deformation and meet the UHF partial discharge detection requirements.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • Machine-Learning-Based Inversion Scheme for Super-Resolution
           Three-Dimensional Microwave Human Brain Imaging

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      Authors: Le-Yi Zhao;Li-Ye Xiao;Yu Cheng;Ronghan Hong;Qing Huo Liu;
      Pages: 2437 - 2441
      Abstract: To realize efficient three-dimensional (3-D) super-resolution whole brain microwave imaging, a new machine- learning-based inversion method with a resolution enhancement technique is proposed. It consists of three parts: a parallel semiconnected backpropagation neural network (SJ-BPNN) scheme, a U-Net scheme, and a modified Akima piecewise cubic Hermite interpolation (MAPCHI) scheme. The parallel SJ-BPNN scheme is first employed to map the measured scattered field data to the preliminary electrical properties’ distribution of human brain. Then, U-Net is used to improve the quality of these preliminary reconstruction results. Finally, the MAPCHI scheme is adopted to greatly improve the resolution of reconstruction results with a very low computational cost. Numerical examples of a normal human brain and a human brain with abnormal scatterers show that the proposed method can achieve accurate high-resolution human brain imaging with 1024 × 1024 × 1024 voxels with a very low computational cost.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • Mutual Coupling Reduction in CP MIMO Crossed-Dipole Antenna Array

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      Authors: Wan Jun Yang;Yong Mei Pan;Shao Yong Zheng;
      Pages: 2442 - 2446
      Abstract: In this letter, a circularly polarized (CP) 1×2 multiple-input–multiple-output (MIMO) crossed-dipole antenna array is investigated. The antenna element consists of a pair of orthogonal linear dipoles, which are connected by two quarter phase-delay lines, generating CP fields. It is found that within the operating CP band, both the excited and coupled crossed-dipole antennas are of circular operation and the mutual coupling is rather strong, but at higher frequency there exists a self-decoupled band (transmission stopband with low |S21|) in which the excited antenna is of elliptical polarization while the coupled antenna is of linear polarization. In order to reduce the mutual coupling level in the operating band and make it applicable, a single metallic post is added in the middle of the MIMO array, shifting the self-decoupled band downwards to the desired CP band. As a result, the port isolation is enhanced by 13 dB and becomes higher than 20 dB within the entire CP bandwidth of 13.2%.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • Sidelobe Suppression for Leaky-Wave Antennas Using a Complementary Paired
           Configuration

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      Authors: Peng-Yuan Wang;Yue-Long Lyu;Fan-Yi Meng;Andreas Rennings;Daniel Erni;
      Pages: 2447 - 2451
      Abstract: In this letter, an effective method is proposed to suppress the overall sidelobes for period-modulated leaky-wave antennas (PM-LWAs). The radiation mechanism of the high sidelobes in PM-LWAs is thoroughly investigated by space harmonic (SH) analysis of the aperture field. It is found that the $n = 0$ SH in PM-LWAs occupies a larger proportion of power than that in periodic LWAs (P-LWAs), resulting in a higher sidelobe level (SLL) in PM-LWAs than that in P-LWAs. An SLL suppression method for PM-LWAs is proposed based on even SH cancellation, which is realized by aligning inversed period modulations in a pair of PM-LWAs. Exciting the PM-LWA pair with equal amplitudes and reversed phases, all radiations from the even SHs are cancelled out and hence the overall sidelobes including the first sidelobe and grating lobe are efficiently suppressed. Prototypes are designed, simulated, fabricated, and experimentally measured. Measured results agree well with simulations, which verify the theoretical predictions. The overall sidelobes are suppressed by more than 10 dB in almost the entire forward region. The radiation of $n = - 2$ SH (grating lobe) and the first sidelobe is reduced by more than 20 and 3.4 dB, respectively.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • A Modified HODLR Solver Based on Higher Order Basis Functions for Solving
           Electromagnetic Scattering Problems

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      Authors: Ningning Zhang;Yongpin Chen;Yi Ren;Jun Hu;
      Pages: 2452 - 2456
      Abstract: In this letter, we present a novel fast direct solver based on a modified hierarchically off-diagonal low-rank (M-HODLR) matrix format with higher order basis functions for analyzing electromagnetic scattering by electrically large objects. The M-HODLR matrix compresses the far-group submatrices by an extended admissibility condition, which enhances the efficiency and accuracy of the original HODLR. To further alleviate the burden of the fast direct solution of the conventional surface integral equation (SIE), the higher order hierarchical vector basis (HOHVB) functions defined over a curved surface are employed. To account for HOHVB, an efficient assembly scheme based on patch coupling is developed to accelerate the adaptive across approximation implementation in M-HODLR. The proposed method can significantly reduce the computational time and memory cost of a conventional SIE solver. Several numerical examples are presented to validate the accuracy and efficiency of the proposed method in solving electrically large objects. Owing to the characteristics of HOHVB, different patch sizes or basis functions with different orders can be chosen according to the local geometry of the object. Therefore, the proposed method is very appealing for large- and multiscale simulations.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • Microwave Attenuation in Wireless Link Caused by Sand and Dust Storms

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      Authors: Yue Xi;Qiang Ma;Li Xie;
      Pages: 2457 - 2461
      Abstract: In this letter, the attenuation by spheroidal sand particles under different relative humidity (RH) is investigated with consideration of contributions of water vapor and excess charges carried by particles, which is much closer to real conditions. The microwave (MW) attenuation will be enhanced when the sand particles are considered as the spheroids. The contributions of RH and excess charges to the MW attenuation are much greater by the spheroidal sand particles than that by the equal-volume spherical ones. The increasing effects of excess charges and RH on the MW attenuation are mutually reinforced. The contribution of water vapor to the MW attenuation by sand–dust storms is significant when the visibility is high, which makes up the gap between the experimental results and calculated results. An improved attenuation model by sand and dust storms is given with an incident wave frequency of 4–45 GHz.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • A Low-RCS Folded Reflectarray Combining Dual-Metasurface and Rasorber

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      Authors: Jian Xu;He-Xiu Xu;Huiling Luo;Yanzhao Wang;Chaohui Wang;
      Pages: 2462 - 2466
      Abstract: A strategy for folded reflectarray with low detectability and enhanced gain is presented. For this purpose, the folded reflectarray is engineered by combining a polarization-conversion focusing metasur face, a frequency selective rasorber (FSR), and a diffusion metasurface. The FSR is composed of a lossy layer and a single-polarized I-shaped slotted frequency selective surface (FSS) between which the diffusive metasurface is inserted for in-band and out-of-band cross-polarized low radar cross-sectional (RCS) reduction. Therein, the antenna exhibits a transmission window and two out-of-band absorptions due to the FSR for copolarized radiation. In contrast to detection, the system operated for both wave incidence. For cross-polarized wave incidence, a wideband RCS reduction is enabled due to the wave-diffusive function of the inserted metasurface. The half profile is guaranteed since the wave bounces two times between the FSS and focusing metasurface. The numerical and experimental results coincide well, both indicating that the low-RCS folded reflectarray achieves a peak gain of 23.5 dB at 10.2 GHz, corresponding to an aperture efficiency of 37.8%. Besides, the antenna achieves 10 dB monostatic RCS reduction within 4.6–8.8 GHz and 9.6–13.8 GHz under copolarization detection and a 10 dB monostatic RCS reduction from 8.4 to 19 GHz under cross-polarization detection. Moreover, good invisibility is also achieved for bistatic RCS reduction.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • Efficient Radiation Pattern Prediction of Array Antennas Based on
           Complex-Valued Graph Neural Networks

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      Authors: Jie Jin;Qian Su;Yan Xu;Zhengrui He;Yu Lu;
      Pages: 2467 - 2471
      Abstract: Antenna design with the traditional numerical methods is a highly computationally expensive task. In this letter, a complex-valued graph neural network (GNN) with residual connections is proposed to efficiently predict radiation pattern for antenna arrays with different geometric structures. The model uses GNN as a backbone, and the topological structure and excitation of the antenna array are encoded into a graph representation. Complex weights and residual connections are designed to improve the accuracy of the model. Experiments are conducted on five kinds of arrays under amplitude–phase control. The experimental results show that the average mean absolute percentage error and the average root-mean-square error of the model on five types of the antenna array are 1.86% and 0.032, respectively, while the time efficiency of the model is six orders of magnitude faster than that of the traditional full-wave simulation.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • Miniaturized Lossy-Layer Scheme For Designing a Frequency Selective
           Rasorber

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      Authors: Hao Zhang;Hang Ye;Zeguo Lu;Wentao Dai;Meng Xiao;Jianjun Jiang;Ling Miao;
      Pages: 2472 - 2476
      Abstract: This letter proposes a miniaturized frequency selective rasorber (FSR) based on parallel-plate capacitors that can be applied in antenna systems to delay the appearance of grating lobes. Compared with traditional solutions, the lossy-layer unit-topology is rearranged to balance a more efficient capacitor C1, fewer resistive lumped elements, and a large inductance L1 in series. Furthermore, the lossless layer is constructed using a third-order frequency selective surface with parallel-plate capacitors. These approaches achieve a rasorber unit size of only 0.035λL, where λL is the wavelength of the lowest absorption frequency. Under normal incidence, the 1 dB transmission band with a bandwidth of 40.9% is obtained at 6 GHz, whereas an absorption rate of over 90% covers 1.5 to 4.05 GHz. Moreover, the FSR exhibits high stability for the dual-polarization and oblique incidence up to 30°. Prototypes were fabricated and measured, verifying the feasibility of the miniaturized design.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • A Butler Matrix-Based Antenna Array With Improved Gain Flatness and
           Sidelobe Levels by Using Pattern-Reconfigurable Subarrays

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      Authors: Han-Jun Zhao;Hui Chu;Xiao-Hua Zhu;Yong-Xin Guo;
      Pages: 2477 - 2481
      Abstract: A pattern-reconfigurable subarray is proposed in this letter for the performance enhancement of Butler matrix (BM)-based antenna arrays. The reconfiguration is conducted at subarray-levels and therefore, requires much fewer lumped components than conventional methods. In the proposed design, the pattern of the subarray is switched to different modes for different scanning regions of the overall array, leading to an improvement of gain flatness and sidelobe levels. The reconfiguration is achieved by a novel reconfigurable coupler. By electronically controlling vias connected to a ground plane which severs as binary switches through PIN diodes, the proposed coupler is characterized by extremely low loss even with the capability of reconfiguration. For validation, a Ku-band prototype consisting of a 4 × 4 BM and four reconfigurable subarrays is designed, fabricated and measured. Measured results indicate that, the achieved gain fluctuation is only about 0.2 dB between the four scanning beams. The SLL is smaller than −12.1 dB while the gain is larger than 13.8 dB in the scanning plane, which are improved by 5.8 and 1.9 dB than its conventional counterparts, respectively.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • A Multiantenna System With High Isolations for Millimeter-Wave Sensing

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      Authors: Zhe Chen;Ya-Xing Wang;Kai-Dong Hong;Tao Yuan;
      Pages: 2482 - 2486
      Abstract: This letter presents a multiantenna system with several superiorities of compact structure, high isolation, and low profile, which can be applied as a millimeter-wave sensor. The proposed multiantenna system includes three probe-fed patch antennas, which are integrated in a limited aperture (1.2·λ0 × 1.2·λ0, λ0 is corresponding to the center frequency at 24.1 GHz). Although the antennas are tightly arranged, high-isolation performance between each two antennas (> 25 dB) is achieved by rotating the antennas by 45° and introducing an X-shaped decoupling structure. Including with the impedance matching layer for measurement, the total thickness of the proposed antenna system is just 0.056·λ0, which is convenient for the integration with radio-frequency integrated circuits. The impedance matching layer is designed as a coplanar-waveguide-transition between the feed probe and the connector for multiantenna measurement in such a compact space. For demonstration, the proposed multiantenna system is fabricated and measured. The good agreement between measurement and simulation guarantees the promising application of this design for radar sensing.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • Co-Design of Dielectric Resonator Antenna and T-Shaped Microstrip Feeding
           Network for Back-Radiation Suppression

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      Authors: Simin Song;Xiaoming Chen;Jianxing Li;Ahmed A. Kishk;
      Pages: 2487 - 2491
      Abstract: In practice, the broadband feeding network on the back side of an antenna can have a nonnegligible effect on the antenna's back radiation due to the feeding network's radiation contribution. Thus, a back-radiation cancellation scheme is proposed by co-designing the antenna and its feeding network to solve this problem. The antenna and its feeding network can be viewed as a two-element array. Their radiation toward the antenna's backward direction can cancel each other when both have equal amplitude and opposite phases along the back direction. A differential fed dielectric resonator antenna (DRA) through a rat-race coupler (${180}^circ $ hybrid coupler) and a T-shaped broadband differential feeding network are compared and analyzed to verify the proposed scheme. In addition, a $1!times!4$ DRA array with a T-shaped broadband differential feeding network in a previous work (where the feeding network's radiation effect on the back side was overlooked) is used for experimental validation of the proposed scheme. Simulations and measurements demonstrate significant back-radiation suppression than the ideal differential feeding network.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • Decoupling Between Two Back-to-Back PIFAs With Continuous Frequency Bands

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      Authors: Weiquan Zhang;Yue Li;Kunpeng Wei;Zhijun Zhang;
      Pages: 2492 - 2496
      Abstract: This letter presents a planar inverted-F antenna (PIFAs) system for Wireless Fidelity 6 (Wi-Fi 6) and Wi-Fi 6E applications with compact size and high isolation. To realize decoupling in a guided way, single-mode structure is proposed based on common mode and differential mode theory. For the demonstration, the mutual coupling between two back-to-back asymmetric PIFAs was reduced by etching two slots on the ground. The measured results show that the two PIFAs, respectively, achieve the impedance bandwidth of 5.14–6.03 GHz and 5.90–7.24 GHz, and the port isolation higher than 17.4 dB across 5.14–7.24 GHz frequency band.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • Improved HMSIW Cavity for Differential Antenna With High Common-Mode
           Rejection

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      Authors: Xuedong Fu;Mingyu Sun;Jiamei Qin;Aixin Chen;
      Pages: 2497 - 2501
      Abstract: In this letter, a differential antenna with high common-mode (CM) rejection is proposed, which consists of dual improved half-mode substrate-integrated waveguide (HMSIW) cavities and a square substrate-integrated waveguide (SIW) coupling-feeding cavity (CFC). First, a novel approach to enhance the differential-mode (DM) radiation performance by flipping the symmetrical TE201 cavity is presented. The two E-field components excited from reversed magnetic walls are superposed in phase. Then, a pair of improved HMSIW cavities with oppositely magnetic walls is adopted to suppress the CM and enhance the uniformity of the radiation pattern on E- and H-planes. The square TE202 CFC with four coupling holes is discussed for the DM excitation. Meanwhile, it is equivalent to a band-stop filter further to improve CM rejection under CM excitation. The four perturbation holes in the CFC for the adjacent E-field isolation are analyzed. Finally, the proposed antenna is fabricated. The measured and simulated results show good agreement. The high CM rejection (27.3 dB) is achieved through the two-step rejection of the radiator and CFC.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • MICS-Band Helical Dipole Antenna for Biomedical Implants

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      Authors: Xiao Fang;Xufeng Du;Michael Bärhold;Qiong Wang;Dirk Plettemeier;
      Pages: 2502 - 2506
      Abstract: This letter presents the design, analysis, and measurement of a miniaturized ($text{7}!times!text{7.5}$ mm) electrically small helical dipole antenna with the introduction of a flexible magnetic sheet of high permittivity and permeability for biomedical implants. The proposed helical dipole, operating at 402–405 MHz Medical Implant Communication Services (MICS) band, supports wider bandwidths (10 dB bandwidth: simulated 33 MHz; measured 49.5 MHz) compared to the state-of-the-art designs. In addition, as a hybrid between a magnetic loop antenna and an electric dipole antenna and operating in the normal mode with small radian (ka < 0.36), enhanced radiation efficiency has been achieved as a result of the magnetic sheet. Measured in-body to on-body transmission verifies the antenna performance.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • Wide-Angle Spoof Surface Plasmon Polariton Leaky-Wave Antenna Exploiting
           Prefractal Structures With Backfire to Nearly Endfire Scanning

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      Authors: Ehsan Farokhipour;Benedikt Sievert;Jan Taro Svejda;Andreas Rennings;Nader Komjani;Daniel Erni;
      Pages: 2507 - 2511
      Abstract: This letter presents a single-layer, wide-angle, low-cost frequency beam scanning leaky-wave antenna (LWA) based on spoof surface plasmon polaritons (SSPPs). Here, two rows of Sierpinski prefractal parasitic patches are placed near an ultrathin planar SSPP waveguide, which can achieve continuous backfire to nearly endfire beam scanning with increasing frequency. The overall width of the proposed antenna is only 0.75$lambda _{text{0}}$ (with $lambda _{text{0}}$ being the wavelength of the lowest operating frequency). This SSPP LWA provides high-performance backfire and broadside radiations due to applying prefractal units. Simulated results show that the proposed SSPP LWA achieves a wide scanning range from −90$^{circ }$ to +58$^{circ }$ within the frequency range of 3–8 GHz. The average gain and radiation efficiency of the antenna are 10.9 dBi and 88%, respectively. An antenna prototype is fabricated and measured. The measured results agree reasonably well with the simulated ones.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • Fast Multinull Steering of Antenna Array

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      Authors: Shen-Yun Wang;Xin-Ran Jin;Pei Liu;Wen Geyi;
      Pages: 2512 - 2516
      Abstract: In this letter, a fast multinull steering technique is demonstrated by a linearly polarized linear antenna array. The new technique is based on the electric fields generated by each antenna element on a far-field arc of the antenna array, which are extracted in advance by simulation or measurement. The power transmission efficiency is used as the performance index to control the pattern nulls. By solving a matrix eigenvalue equation, in which the matrix is made up by selecting the corresponding electric fields on different positions on the arc standing for the null directions, the eigenvector corresponding to the zero eigenvalue is identified and used as the optimized distribution of excitations (ODEs) for the antenna array. Single-null and multinull patterns are tested from the ODEs and the results indicate that the number and directions of the multiple nulls can be controlled in the elevation space. The simulated and measured 2-D null patterns are shown in good agreement.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • Wideband and Ultrathin 2×2 Dipole Array Antenna for 5G mmWave
           Applications

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      Authors: Seongjung Kim;Sangwook Nam;
      Pages: 2517 - 2521
      Abstract: This letter proposes a wideband (24–40 GHz) and ultrathin (0.76 mm) 2×2 dipole array antenna for fifth-generation (5G) millimeter-wave (mmWave) applications. For the ultrathin array antenna, it is a challenge to match the antenna input impedance because it usually has an extremely low value. Herein, a tightly coupled frequency selective surface is proposed to provide additional resonances, and a capacitively coupled feeding method and H-walls are employed to increase the bandwidth. Furthermore, consistent measurement results are guaranteed by vertical launch connectors, and the calibration process owing to the distortion at the connectors is briefly described. In addition, the cumulative distribution function of effective isotropically radiated power scan patterns is presented at various frequencies. Finally, the performance of the proposed array antenna is compared with those of state-of-the-art mmWave array antennas.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • Composite Right/Left-Handed Leaky-Wave Antenna With High Scanning
           Rate

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      Authors: Wanghui Yang;Zhen Peng;Jishan Ren;Jianjun Gao;Guohua Zhai;
      Pages: 2522 - 2526
      Abstract: The scanning rate of a composite right/left-handed (CRLH) leaky-wave antenna (LWA) is usually determined by the dispersive behavior of the corresponding CRLH unit cell. In this letter, a novel CRLH unit cell with high dispersive behavior is proposed and investigated. The unit cell is formed by four stubs embedded in a rectangular ring patch, which is grounded with several metal vias. The right-handed characteristic is enhanced by the ring patch, while the left-handed characteristic is reduced by the vias and the gaps between the patch and the stubs. Then, the unit cell is applied to design an LWA with high scanning rate. The measured result shows that the seamless scanning angle of the antenna prototype is 130° (−65° to +65°) within a frequency range from 9.3 to 9.93 GHz (i.e., 6.6% for fractional bandwidth). Therefore, the proposed LWA antenna is with a high scanning rate up to 19.7°/%BW.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • Dual-Polarized Wide-Angle Scanning Linear Phased Array Antenna Design With
           High Polarization Isolation

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      Authors: Han Zhou;Junping Geng;Kun Wang;Chong He;Xianling Liang;Ronghong Jin;
      Pages: 2527 - 2531
      Abstract: This letter presents a dual-polarized low-profile linear phased array antenna design achieving one-dimensional wide-angle scanning with high polarization isolation. The dual-polarized antenna is constructed based on a metasurface serving different purposes for two polarization cases to achieve high polarization isolation while providing a low profile as a whole. It works as artificial magnetic conductor for x-polarization and radiator for y-polarization. To achieve wide-angle scanning, surface wave effect is exploited for x-polarization while for y-polarization widebeam active element patterns is implemented with a small array spacing of 0.42 λ0 applied. To verify the design, a 1×8 linear array was fabricated and tested. Measured and simulated results both demonstrate that, within a wide operating band, the proposed dual-polarized antenna has a high port-to-port polarization isolation over 29 dB with a low profile of 0.06 λ0. The measured results show that for x-polarization, the linear array can steer its main beam up to 81°, while for y-polarization, it can steer the main beam up to 70°. The cross-polarization levels can maintain below −20 dB during scanning in the general.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • Transparent Ultrawideband Halved Coplanar Vivaldi Antenna With Metal Mesh
           Film

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      Authors: Bian Wu;Xiao-Yuan Sun;Hao-Ran Zu;Hong-Hao Zhang;Tao Su;
      Pages: 2532 - 2536
      Abstract: In this letter, a transparent ultrawideband (UWB) halved coplanar Vivaldi antenna (HCVA) with metal mesh film (MMF) is proposed. Based on the equivalence principle, the halved type antenna is achieved by replacing a radiation fin with the ground plane. The proposed HCVA has the advantages of UWB impedance matching, miniaturized aperture size, high directivity, and simple feed structure. By employing MMF with a low sheet resistance of 0.35 Ω/sq and high optical transmittance above 72% in the radiation fin and ground plane, the antenna is entirely transparent. An example transparent HCVA is fabricated and measured. According to the simulated and measured results, most of the reflection coefficient is below –10 dB from 0.78 to 20 GHz. Moreover, the peak realized gain reaches 10.4 dBi with the compact size of 0.32×0.47×0.052λL3, where λL is the wavelength at the lowest operating frequency.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • High-Efficiency 2-D Multibeam Rectenna Based on Gain Enhanced Patch Array

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      Authors: Xiaokang Qi;Zhiwei Xu;Huan Li;
      Pages: 2537 - 2541
      Abstract: Wireless power transfer (WPT) is a promising technique used in many applications, like smart terminals, IoT equipment, etc. For WPT systems based on RF rectifying, working in very low power density situation, high-gain rectenna system is of great essential. According to the antenna theory, for the same physical size, higher gain means higher aperture efficiency, which means more power will be received by the antenna instead of being scattered. However, high-gain rectenna usually means narrow beam width and high directivity, which is contradictory to a power harvesting system that need to have wide spatial coverage. In order to realize high aperture efficiency and wide spatial coverage at the same time, a two-dimensional (2-D) multibeam rectenna based on gain enhanced patches and hybrid coupler is proposed, which can improve the 2-D spatial coverage and achieve the maximum 81.5% power receiving efficiency. Simulation and experimental results indicate that the power receiving efficiency is more than 50% with 100° coverage in main beam cutting plane, 70° in H-plane, and 90° in E-plane. The practicality of this letter is fully verified, which can help to provide a guidance for the design of rectenna.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • A Method for Transmitarray Antenna Profile Reduction Based on Ray Tracing
           Principle

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      Authors: Tang-Jing Li;Guang-Ming Wang;Jian-Gang Liang;Hai-Peng Li;
      Pages: 2542 - 2546
      Abstract: In this letter, a method named double phase-compensation is first proposed to drastically reduce the profile of traditional transmitarray antenna (TA) based on ray tracing principle. Previously, the folded transmitarray antenna (FTA) has realized the profile reduction to 1/3. It is known that there is an urgent need for more compact antenna nowadays. If the FTA's profile is further reduced, the focus-to-diameter (F/D) ratio should be decreased which will result in obvious aperture efficiency reduction. To further reduce the FTA's profile with unchanged F/D for keeping high efficiency, the extra phase compensation is innovatively added on the FTA's reflector. Hence the TA's profile can be reduced to lower than 1/3 and be flexibly adjusted as needed. Three FTA models are designed for comparison and demonstration. The simulation and experimental results indicate that the extra phase compensation successfully alleviates the efficiency drop caused by directly reducing the profile of FTA. Significantly, the method provides an efficient approach to further improve the compactness of antenna system and is very meaningful for TA miniaturization.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • A Comparative Study of Error Vector Magnitude Measurement in a
           Reverberation Chamber

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      Authors: Feng Fang;Wenjun i;Wenjun Xia;Chong Li;Lei Xing;Qian Xu;
      Pages: 2547 - 2551
      Abstract: This letter shows a comparative analysis between the conventional and reverberation chamber (RC) measurements of error vector magnitude (EVM). The conventional methods, including direct link (DL) and anechoic chamber (AC), have been used to measure EVM for several years. However, the over-the-air testing of devices under test (DUT) is emphasized, and the EVM measurement in RC is a difficult question. For mass production testing, instead of using two chambers (RC and AC), it is expected to integrate EVM testing into the existing RC measurement system to give a pass/fail conclusion quickly. Hence, we measured EVM in 2 GHz (2412 MHz) and 5 GHz (5180 MHz) using RC, AC, and DL methods. From the measurement results, we find that the measured EVM is repeatable, stable, and insensitive to the location of DUT. Besides, the measured EVMs obtained from all scenarios deteriorate with the decrease of received power. Comparing the results from RC with that from the conventional methods, it could be concluded that with the reduction of multipath effect, the measured EVMs approach to the ideal values measured in AC. The differences among the methods could be used to calibrate the measured EVMs and give a pass/fail conclusion efficiently for mass production.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • Low-Cost Wide-Angle Beam-Scanning Transmitarray Antennas Using Lens-Loaded
           Patch Elements: A Proof-of-Concept Study

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      Authors: Wei Hu;Mingyang Dong;Qi Luo;Yuanming Cai;Lehu Wen;Tian-Xi Feng;Wen Jiang;Steven Gao;
      Pages: 2552 - 2556
      Abstract: In this letter, a novel design concept to achieve a low-cost wide-angle beam-scanning transmitarray (TA) using lens-loaded patch (LLP) elements is presented. In this design, each TA element consists of a beam switchable transmitting element, a group of receiving elements, and a signal via. The received powers of a 2×2 subarray are first combined and then transmitted to the corresponding LLP element, where the phases of the transmitted signals are manipulated for beamforming. Compared with the conventional designs, the phase shifters (PSs) can be multiplexed and the number of PSs is effectively eliminated by 75%, which significantly decreases the hardware cost. By employing multiple patches as the feed of the lenses, reconfigurable radiation patterns are obtained, and by properly choosing the transmitting patches, the developed TA achieves a wide-angle two-dimensional beam scanning within ±60° with stable gains. To validate the design concept, passive prototypes with a center frequency of 12.5 GHz are simulated, fabricated, and tested. The measured results show that the aperture efficiency is 30.1%, 19.4%, and 14.1% for beams steered to 0°, 30°, and 60° at 12.5 GHz, respectively. The beam coverage of ±60° with a less than 3.5 dB scanning loss in the H-plane is obtained.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
  • 2022 List of Reviewers

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      Pages: 2557 - 2562
      Abstract: Presents the list of reviewers who contributed to this publication in 2022.
      PubDate: Dec. 2022
      Issue No: Vol. 21, No. 12 (2022)
       
 
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