Iet Microwaves Antennas & Propagation最新文献_第5页

The extended resonant modal theory and its applications 扩展共振模态理论及其应用

IF 1.7 4区计算机科学

Iet Microwaves Antennas & Propagation Pub Date : 2024-03-05 DOI: 10.1049/mia2.12469

Ruqi Xiao, Wen Geyi, Guo Yang, Wen Wu

引用次数: 0

High-gain tapered monopulse antenna based on octuple excitation method in diffusion bonding technology at W-band 基于扩散键合技术八倍激发方法的 W 波段高增益锥形单脉冲天线

IF 1.7 4区计算机科学

Iet Microwaves Antennas & Propagation Pub Date : 2024-03-05 DOI: 10.1049/mia2.12456

Adham Mahmoud, Takashi Tomura, Mauro Ettorre, David González-Ovejero, Ronan Sauleau, Jiro Hirokawa

{"title":"High-gain tapered monopulse antenna based on octuple excitation method in diffusion bonding technology at W-band","authors":"Adham Mahmoud, Takashi Tomura, Mauro Ettorre, David González-Ovejero, Ronan Sauleau, Jiro Hirokawa","doi":"10.1049/mia2.12456","DOIUrl":"10.1049/mia2.12456","url":null,"abstract":"The authors present the design, fabrication and testing of a W-band monopulse antenna. This antenna consists of three main building blocks: an array with 48 × 48 slots, a tapered corporate-feed network and a comparator. The comparator has four input ports to generate sum and difference patterns in orthogonal cardinal planes for monopulse operation. A novel octuple excitation is adopted for the corporate network to achieve a side lobe level lower than −20 dB for the sum patterns and simultaneously reduce drastically the manufacturing complexity. Diffusion bonding technology is used for fabrication. Twenty-four etched copper sheets with a thickness of 0.2 mm are stacked to realise the prototype. The total size of the antenna is <math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>40.76</mn>\u0000 <mo>×</mo>\u0000 <mn>40.76</mn>\u0000 <mo>×</mo>\u0000 <mn>1.51</mn>\u0000 <msubsup>\u0000 <mi>λ</mi>\u0000 <mn>0</mn>\u0000 <mn>3</mn>\u0000 </msubsup>\u0000 </mrow>\u0000 <annotation> $40.76times 40.76times 1.51{lambda }_{0}^{3}$</annotation>\u0000 </semantics></math>, with λ0 being the wavelength at the centre frequency (94 GHz). The antenna presents an isolation better than 12 dB among the input ports in the 84–100 GHz band. The realised measured gain is 40.7 dBi at 94 GHz. The measured 3-dB gain bandwidth is 17.4%. The difference patterns at 94.0 GHz present null depths of −24.0, −18.0, −17.5, and −17.4 dB, in the E-, H-, 45°-, and 135°-planes, respectively.","PeriodicalId":13374,"journal":{"name":"Iet Microwaves Antennas & Propagation","volume":"18 5","pages":"317-330"},"PeriodicalIF":1.7,"publicationDate":"2024-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/mia2.12456","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140054680","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A 3D printed low-profile wideband circularly polarised elliptical integrated lens antenna 3D 打印扁平宽带圆极化椭圆集成透镜天线

IF 1.7 4区计算机科学

Iet Microwaves Antennas & Propagation Pub Date : 2024-02-29 DOI: 10.1049/mia2.12462

Bin Xu, Bing Zhang, Xiao An

{"title":"A 3D printed low-profile wideband circularly polarised elliptical integrated lens antenna","authors":"Bin Xu, Bing Zhang, Xiao An","doi":"10.1049/mia2.12462","DOIUrl":"10.1049/mia2.12462","url":null,"abstract":"The authors presents a low-profile wideband circularly polarised (CP) millimetre-wave (mmWave) elliptical integrated lens antenna (ILA) fabricated by dielectric 3D printing technology. The proposed lens is integrated with a dielectric polariser and an air cavity for phase compensation, which can transfer incident waves from linearly polarised (LP) to planar CP waves over a wide bandwidth. Compared to the classic bifocal ILA, the proposed lens has a low profile. The phase compensation is performed by introducing a specifically shaped air cavity, which greatly reduces the length and weight of the lens. The polariser causes the two electric field components Ex and Ey to degenerate with an orthogonal phase difference, which results in the wideband characteristics of the antenna. The polariser, air cavity and lens can be conveniently and precisely fabricated by low-cost 3D printing technology. Measurements show that the proposed ILA has a wide axial ratio (AR) bandwidth of 21.9–32.6 GHz, while the gain reaches 22.54 dBic with a 38% size reduction and a 60.7% weight reduction. Benefiting from the low profile, high gain, wide bandwidth and low cost, the proposed ILA has great potential to be the candidate antenna for 5G applications and satellite communications.","PeriodicalId":13374,"journal":{"name":"Iet Microwaves Antennas & Propagation","volume":"18 4","pages":"272-279"},"PeriodicalIF":1.7,"publicationDate":"2024-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/mia2.12462","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140009935","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Electromagnetic radiation estimation at the ground plane near fifth-generation base stations in China by using machine learning method 利用机器学习方法估算中国第五代基站附近地平面的电磁辐射

IF 1.7 4区计算机科学

Iet Microwaves Antennas & Propagation Pub Date : 2024-02-28 DOI: 10.1049/mia2.12467

Dan Shi, Wanqing Li, Keyi Cui, Cheng Lian, Xiaoyong Liu, Zheng Qi, Hui Xu, Juejia Zhou, Zhao Liu, Hua Zhang

{"title":"Electromagnetic radiation estimation at the ground plane near fifth-generation base stations in China by using machine learning method","authors":"Dan Shi, Wanqing Li, Keyi Cui, Cheng Lian, Xiaoyong Liu, Zheng Qi, Hui Xu, Juejia Zhou, Zhao Liu, Hua Zhang","doi":"10.1049/mia2.12467","DOIUrl":"10.1049/mia2.12467","url":null,"abstract":"A novel method based on machine learning is proposed to estimate the electromagnetic radiation level at the ground plane near fifth-generation (5G) base stations. The machine learning model was trained using data from various 5G base stations, enabling it to estimate the electric field intensity at any arbitrary radiation point when the base station provides service to different numbers of 5G terminals which are in different service modes. The inputs required for the model include the transmit power of the antenna, the antenna gain, the distance between the 5G base station and 5G terminals, terminal service modes, the number of 5G terminals and the environmental complexity around the 5G base station. Experimental results demonstrate the feasibility and effectiveness of the estimation method, with the mean absolute percentage error of the machine learning model being approximately 5.98%. This level of accuracy showcases the reliability of the approach. Moreover, the proposed method offers low costs when compared with on-site measurements. The estimated results can be utilised to reduce test costs and provide valuable guidance for optimal site selection, thereby facilitating radio wave coverage or electromagnetic radiation regulation of 5G base stations.","PeriodicalId":13374,"journal":{"name":"Iet Microwaves Antennas & Propagation","volume":"18 6","pages":"391-401"},"PeriodicalIF":1.7,"publicationDate":"2024-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/mia2.12467","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140009928","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A compact single-layer reflective metasurface for high-efficiency polarisation conversion applications in C and X bands 用于 C 波段和 X 波段高效偏振转换应用的紧凑型单层反射元表面

IF 1.7 4区计算机科学

Iet Microwaves Antennas & Propagation Pub Date : 2024-02-26 DOI: 10.1049/mia2.12465

Kd. M. Raziul Islam, Ardavan Rahimian, Gabriel G. Machado, Muhammad Ali Babar Abbasi, Adnan Ahmad Cheema, Brian J. Meenan

{"title":"A compact single-layer reflective metasurface for high-efficiency polarisation conversion applications in C and X bands","authors":"Kd. M. Raziul Islam, Ardavan Rahimian, Gabriel G. Machado, Muhammad Ali Babar Abbasi, Adnan Ahmad Cheema, Brian J. Meenan","doi":"10.1049/mia2.12465","DOIUrl":"10.1049/mia2.12465","url":null,"abstract":"The authors design and experimentally analyse an anisotropic metasurface for the simultaneous conversions of linear cross and circular polarisations in the C and partial X bands. The proposed compact structure utilises a dual-cut square-ring resonator and a square patch on an FR4 substrate above a ground plane. The full-wave simulations exhibit over 92% efficiency in cross-conversion over a fractional bandwidth (BW) of 52.3%. The proposed metasurface efficiently converts linear to circular polarisation in two different bands, achieving left-hand circularly polarised and right-hand circularly polarised efficiencies exceeding 93% and 89%, respectively. The compact unit-cell with dimension 0.22λ × 0.22λ attains stable polarisation transformation efficiency rates exceeding 80% up to 40° incident angles. The design is adaptable for efficient wide BW across both lower and higher (millimetre-wave) frequencies through scaling. A prototype of the proposed polarisation converter (PC) was realised and validated effectively in measurements, aligning well with simulations. This PC features a novel and simple structure with multifunctional wideband operation, stable incident angle output, polarisation insensitivity, and scalability, making it an efficient front-end for various radio frequency applications, including polarisation control and polarisation transformers.","PeriodicalId":13374,"journal":{"name":"Iet Microwaves Antennas & Propagation","volume":"18 5","pages":"369-381"},"PeriodicalIF":1.7,"publicationDate":"2024-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/mia2.12465","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139987620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Analytical modelling with experimental validation of electromagnetic Halbach arrays in wireless power transfer systems 无线电力传输系统中电磁哈尔巴赫阵列的分析建模与实验验证

IF 1.7 4区计算机科学

Iet Microwaves Antennas & Propagation Pub Date : 2024-02-23 DOI: 10.1049/mia2.12460

Tamuno-omie Gogo, Dibin Zhu

引用次数: 0

Design and fabrication of waveguide-based graded refractive index Rotman lens with an improved insertion loss at Ka-band 设计和制造基于波导的梯度折射率罗特曼透镜，改善 Ka 波段的插入损耗

IF 1.7 4区计算机科学

Iet Microwaves Antennas & Propagation Pub Date : 2024-02-22 DOI: 10.1049/mia2.12457

Milad Hadei, Gholamreza Dadashzadeh

{"title":"Design and fabrication of waveguide-based graded refractive index Rotman lens with an improved insertion loss at Ka-band","authors":"Milad Hadei, Gholamreza Dadashzadeh","doi":"10.1049/mia2.12457","DOIUrl":"10.1049/mia2.12457","url":null,"abstract":"The design and optimisation of a five-cascade layer Rotman Lens based on waveguide with a graded refractive index at Ka-band frequency are presented. The proposed lens incorporates 5 layers within the cavity, utilises a modified three focal Rotman lens design methodology to achieve perfect phasing for true time delay beam steering, and optimises each layer's parameters such as refractive index, vertex location, and contour angle to improve insertion loss between input ports and output array elements. This approach enhances energy concentration between input and output ports, reducing spillover to dummy ports. The graded layers are formed using periodic cubic metallic posts with varying heights within a parallel plate waveguide. The results show an average improvement in the insertion loss of 16% and a peak improvement of 48% across the bandwidth when compared to conventional Rotman lenses. The normalised average phase error across the array elements for all beam ports excitation is 4 × 10−3 and the peak degradation of the main beam during beam scanning from 0° to ±22° varies from 0.7 to 1 dB at different frequencies operating in the Ka-band (24–30 GHz) with potential applications for 5G communications. The simulation results demonstrate good agreement with the measurement results.","PeriodicalId":13374,"journal":{"name":"Iet Microwaves Antennas & Propagation","volume":"18 5","pages":"331-341"},"PeriodicalIF":1.7,"publicationDate":"2024-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/mia2.12457","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139953007","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Design of an efficiency enhanced wideband Doherty power amplifier based on synthesising of a modified harmonic-control load modulation network 基于合成改进型谐波控制负载调制网络的增效型宽带 Doherty 功率放大器的设计

IF 1.7 4区计算机科学

Iet Microwaves Antennas & Propagation Pub Date : 2024-02-18 DOI: 10.1049/mia2.12464

A. M. Elelimy Abounemra, Mohamed Helaoui, Fadhel M. Ghannouchi

{"title":"Design of an efficiency enhanced wideband Doherty power amplifier based on synthesising of a modified harmonic-control load modulation network","authors":"A. M. Elelimy Abounemra, Mohamed Helaoui, Fadhel M. Ghannouchi","doi":"10.1049/mia2.12464","DOIUrl":"10.1049/mia2.12464","url":null,"abstract":"A design of a broadband Doherty power amplifier (DPA) using a novel harmonic control network (HCN) is presented. The DPA structure focused on manipulating harmonic components using this new HCN to enhance the bandwidth of operation and power efficiency. The proposed HCN combines a third harmonic suppression network (THSN) with the second harmonic impedance inverter circuit (SHIIC). In the design, the second harmonic component of the main transistor and the peaking transistor are short-circuited by their associated SHIIC. Additionally, the carefully designed SHIIC and THSN circuit placed between the main and peaking transistors realise open circuit conditions at the third harmonic for both transistors at the saturation state and back-off regions. Side by side with the aid of the properly designed post-matching tuned network (PMTN), these harmonic loading conditions make both amplifiers to operate in continuous Class-F modes with enhanced-added efficiencies over wideband conditions. As a result, a succession of highly efficient DPA modes can be formed over a continuous frequency range in the full Doherty region, resulting in a reduced-size enhanced power efficiency wideband DPA. For verification, a wideband DPA operating from 1.1 to 1.8 GHz was designed and implemented using the proposed topology. The measured drain efficiency of the implemented DPA at 6-dB back-off is 52.5%–67.5%, while the saturated power across the specified bandwidth is 43–43.7 dBm. The fabricated DPA exhibits an average efficiency of 48.7%–59.4%, when supplied by a 40-MHz long-term evolution (LTE) signal with a 7.5-dB peak-to-average power ratio (PAPR). Performing digital pre-distortion (DPD) improves the adjacent channel power ratio (ACLR) from −25.8 dBc to −47.6 dBc.","PeriodicalId":13374,"journal":{"name":"Iet Microwaves Antennas & Propagation","volume":"18 5","pages":"356-368"},"PeriodicalIF":1.7,"publicationDate":"2024-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/mia2.12464","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139910672","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Physics-informed surrogates for electromagnetic dynamics using Transformers and graph neural networks 使用变压器和图神经网络的电磁动力学物理信息代用器

IF 1.1 4区计算机科学

Iet Microwaves Antennas & Propagation Pub Date : 2024-02-15 DOI: 10.1049/mia2.12463

O. Noakoasteen, C. Christodoulou, Z. Peng, S. K. Goudos

{"title":"Physics-informed surrogates for electromagnetic dynamics using Transformers and graph neural networks","authors":"O. Noakoasteen, C. Christodoulou, Z. Peng, S. K. Goudos","doi":"10.1049/mia2.12463","DOIUrl":"10.1049/mia2.12463","url":null,"abstract":"A novel use case for two data-driven models, namely, a Transformer and a convolutional graph neural network (CGNN) is proposed. The authors propose to use these models for emulating the dynamics of electromagnetic (EM) propagation and scattering. The Transformer translates a past sequence into a future sequence by constructing representations from the past and using it to predict the future, taking all of its own previous predictions as input at each step of prediction. The CGNN updates the current state of attribute vectors of each node by passing it information (messages) from all of its neighbouring nodes. We train these models with FDTD simulations of plane waves propagating and scattering from PEC objects. The authors demonstrate that, within the bounds of computational resources, the Transformer can be utilised as a surrogate for EM dynamics, providing 14× speed-up, while the CGNN can be utilised as a next-frame predictor, providing 9× speed-up. When comparing the accuracy of these two models with the authors’ previously developed Encoder-Recurrent-Decoder (ERD) model, it is observed that the error for both the Transformer and the CGNN remains within the same bound for the ERD model. To the best of the authors’ knowledge, this work is the first to utilise the Transformer as a surrogate for EM dynamics.","PeriodicalId":13374,"journal":{"name":"Iet Microwaves Antennas & Propagation","volume":"18 7","pages":"505-515"},"PeriodicalIF":1.1,"publicationDate":"2024-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/mia2.12463","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139752611","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Autoregressive modelling for Sub-THz spatio-temporal wideband scattered reflection coefficient measurement of complex structures 用于测量复杂结构的次 THz 时空宽带散射反射系数的自回归模型

IF 1.1 4区计算机科学

Iet Microwaves Antennas & Propagation Pub Date : 2024-02-13 DOI: 10.1049/mia2.12461

Demos Serghiou, Mohsen Khalily, Ali Ali, Tim Brown, Rahim Tafazolli

{"title":"Autoregressive modelling for Sub-THz spatio-temporal wideband scattered reflection coefficient measurement of complex structures","authors":"Demos Serghiou, Mohsen Khalily, Ali Ali, Tim Brown, Rahim Tafazolli","doi":"10.1049/mia2.12461","DOIUrl":"10.1049/mia2.12461","url":null,"abstract":"The authors present spatio-temporally resolved wideband measurements of Sub-Terahertz (Sub-THz) reflection coefficients in the frequency range of 92–110 GHz. A stochastic model for single reflection fixed links that is capable of modelling random scattering from small-scale discontinuities such as those encountered in complex structures in walls and partitions of buildings is presented. The model auto-regressively produces filter coefficients that are fed into an Infinite-Impulse-Response (IIR) filter which convolves them with the spatio-temporal series in order to generate the next output sample based on previous observations. The IIR filter allows for flexible stochastic generation of samples, and its parameters can be adjusted as needed to suit different channel conditions. A total of 20 suitable start-up filter coefficients are generated from 21.7 % of the sample size for each complex delay tap distribution, which corresponds to 50 complex instances of the channel. These coefficients are then utilised to validate the remaining measured sample set. The model is in quantitative agreement with measurement statistics and can be used to construct relatively simple modified reflection coefficients that can be used in micro-cellular ray-optical network planning tools.","PeriodicalId":13374,"journal":{"name":"Iet Microwaves Antennas & Propagation","volume":"18 7","pages":"494-504"},"PeriodicalIF":1.1,"publicationDate":"2024-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/mia2.12461","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139752359","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0