IEEE Open Journal of Antennas and Propagation - OJAP

[Electromagnetic-Informed Generative Models for Passive RF Sensing and Perception of Body Motions]

Stefano Savazzi, Federica Fieramosca, Sanaz Kianoush, Michele D’Amico and Vittorio Rampa discuss two popular techniques, namely Variational Auto-Encoders (VAEs) and Generative Adversarial Networks (GANs), and their adaptations to incorporate relevant electromagnetic (EM) body diffraction methods. The proposed EM-informed GNN models are verified against classical EM tools driven by diffraction theory, and validated on real data. The paper explores emerging opportunities of GNN tools targeting real-time passive RF sensing in communication systems with dense antenna arrays. Proposed tools are also designed, implemented, and verified on resource constrained wireless devices.

Read their article here: https://ieeexplore.ieee.org/document/10542343

[Experimental Phase-Encoded Linear Sampling Method Imaging With a Single Transmitter and Receiver]

Matthew J. Burfeindt, Hatim F. Alqadah and Scott Ziegler evaluate the phase-encoded linear sampling method (PE-LSM) using experimental data. They collect synthetic aperture data in an anechoic chamber using only a single transmit-receive channel. With the aid of a monostatic-to-multistatic transform, they generate reconstructions of each target via the PE-LSM. The results evince significant improvements in fidelity to the true target geometries compared to imagery generated by both conventional LSM processing and a conventional backprojection-based radar approach.

Read their article here: https://ieeexplore.ieee.org/document/10508577

[Synthesis and Design of 3-D Microwave Absorber With 70° Angular Stability for C-Band and X-Band]

Tian-Xi Feng, Lei Zhu and Hui Li present the synthesis and design of 3-D microwave absorber with 70° angular stability for C-band and X-band. The operating principle is firstly investigated, where the absorber is considered as an energy convertor. With the help of our proposed universal equivalent transmission line (TL) model, the absorptive performance can be accordingly synthesized. Then, a design method for efficient absorption under large angles is presented. By selecting a proper synthesized angle (SA), the angular stability can be effectively improved.

Read their article here: https://ieeexplore.ieee.org/document/10506238
This paper is featured in the Special Section on Recent Advances on Absorbers/Rasobers and Their Applications on Antennas and EMC

[Miniaturized Design of Dual Transmission Frequency Selective Rasorber With Wide Angular Stability]

Mehran Manzoor Zargar, Archana Rajput, Kushmanda Saurav propose a miniaturized design of dual transmission frequency selective rasorber (FSR) with absorption-transmission-absorption-transmission (A-T-A-T) feature. Initially, low frequency resonators are incorporated on the square ring shaped lossy resistive layer for expanding the broad absorption towards the lower spectrum of frequency. Then the dual bandpass frequency selective surface (FSS) with transmission bands lying within the absorption spectrum is integrated with the resistive layer. Further, a cross-loop resonator is integrated inside the square ring of the resistive layer due to which a dual transmission pole is achieved through the resistive layer aligning with the dual operating frequencies of bandpass FSS.

Read their article here: https://ieeexplore.ieee.org/document/10485190

This paper is featured in the Special Section on Recent Advances on Absorbers/Rasobers and Their Applications on Antennas and EMC

[Cusp Phased Metasurfaces for Wideband RCS Reduction Under Broad Angles of Incidence]

Mustafa K. Taher Al-Nuaimi, William G. Whittow, Guan-Long Huang and Rui-Sen Chen presents an efficient and effective design approach of the phase distribution calculation across metasurface for significant radar cross section (RCS) reduction of a circular polarization (CP) and liner polarization (LP) radar waves. The RCS reduction using the proposed design approach is achieved by imposing a novel cusp phase mask (which is usually used to generate 3D self-accelerating and self-healing cusp beams) at each geometric phased anisotropic unit cell composing the proposed cusp phased metasurface.

Read their article here: https://ieeexplore.ieee.org/document/10361551/

This paper is featured in the Special Section on Recent Advances on Absorbers/Rasobers and Their Applications on Antennas and EMC

[A Step-by-Step Design Methodology for Broadband Tunable Microwave Metasurface Absorbers Using Theory of Characteristic Modes]

Zihao Ning, Mengmeng Li, Dazhi Ding, Xia Ai, Jiaqi Liu and Chao-Fu Wang develope a characteristic mode (CM)-based design methodology for the reconfigurable microwave metasurface absorbers (MMA) with using commercially available substrates. Theoretical intrinsic connection between modal behaviors and absorption properties is first formulated for the design of the structures. As a proof of the method, a broadband MMA consisting of butterfly elements is step-by-step designed. The positions and values of the impedance loading are determined based on the modal significances and modal currents for broadband operation. The absorption performance is evaluated by the formulated theoretical model and verified by full-wave simulation.

Read their article here: https://ieeexplore.ieee.org/document/10333076/

This paper is featured in the Special Section on Recent Advances on Absorbers/Rasobers and Their Applications on Antennas and EMC

Special Section on Recent Advances on Absorbers/Rasobers and Their Applications on Antennas and EMC is available now!

We would like to thank Guest Editors Guest Editors Peng Mei, Ahmed Abdelmottaleb Omar, Bo Li, Shuai Zhang and Wonbin Hong for their time and contribution. The special section features 4 articles and can be viewed here:

https://ieeexplore.ieee.org/xpl/topics.jsp?punumber=8566058&refinements=SpecialSection:Recent%20Advances%20on%20Absorbers%2FRasobers%20and%20Their%20Applications%20on%20Antennas%20and%20EMC

[Compact and Broadband Substrate Integrated Dielectric Resonator Antenna Suitable for 5G Millimeter-Wave Communications]

Jie-Er Zhang, Qinfang Zhang, Wei Qin, Wen-Wen Yang and Jian-Xin Chen proposes a compact and broadband substrate-integrated dielectric resonator antenna (SIDRA) suitable for 5G millimeter-wave band applications. Four operating modes from three resonators, including TE111 and TE131 modes from the DR, slot mode from the H-shaped feeding slot, and patch mode from the inserted ring patch, are excited to achieve a bandwidth of 61.9% (24-45.5 GHz) with a compact size of
0.37λ0×0.37λ0×0.125λ0 . The proposed DRA can be extended to an array with ∼0.5λ0 element interval to obtain wide-angle beam scanning capability.

Read their article here: https://ieeexplore.ieee.org/document/10265196/

This paper is featured in the Special Section on Advanced Beam-Forming Antennas for Beyond 5G and 6G

[A Dual-Beam Filtering Antenna Based on Dual-Mode Patch Loaded With π-Shaped Vias]

Lingyan Zhang, Tiannan Ni, Jin Shi, Gu Liu and Kai Xu utilize a dual-beam filtering patch antenna is proposed, wherein a symmetrical π-shaped metal vias-loaded dual-mode patch and a cross-shaped metal strip. The dual-mode patch resonator is realized through the loading of metal vias in the weak field region of mode TM21, which effectively moves mode TM01 closer to TM21. Using a cross-shaped metal strip to excite the dual-mode patch resonator not only provides a reflection zero and broadens the bandwidth, but also generates two radiation nulls through zero coupling, thus improving the frequency selectivity.

Read their article “” here: https://ieeexplore.ieee.org/document/10399964/

[A Center-Fed Beam-Steerable Series Antenna Array With a Wide Matching Bandwidth]

Sungeun Kim, Haegwon Park and Byung-Wook Min present a center-fed beam-steerable series antenna array that has both a wide matching bandwidth and easy control. The proposed matched feeding network for the series array is composed of impedance transformers and voltage-controlled phase shifters, and has a fractional bandwidth of 74%. The phase shifters are designed in a reflection-type configuration to minimize loss and reduce size. The 3-way power divider used in the proposed center-fed series array enable beam steering with only two control voltages for phase shifters.

Read their article here: https://ieeexplore.ieee.org/document/10438832/

This paper is featured in the Special Section on Advanced Beam-Forming Antennas for Beyond 5G and 6G

[A WLAN Dual-Polarized Beam-Reconfigurable Antenna]

Saiju Li, Meie Chen, Zheng Li, Jianqiang Chen and Junhong Wang develop a novel wireless local area network (WLAN) antenna with dual-polarized and beam-reconfigurable ability for WLAN 2.4 GHz band application. The antenna is composed of a horizontally polarized (HP) antenna and a vertically polarized (VP) antenna. The radiation pattern of the HP antenna can be switched between an omnidirectional beam and four directional beams in the azimuth plane, while the VP antenna can generate an omnidirectional beam and eight directional beams. Then the antenna prototype is fabricated and measured.

Read their article here: https://ieeexplore.ieee.org/document/10461076/

This paper is featured in the Special Section on Advanced Beam-Forming Antennas for Beyond 5G and 6G

[Modeling of the Fault Detection Problem for a 3-D Hybrid Antenna Array: Analysis and Evaluation]

Somayeh Komeylian and Christopher Paolini implement the ADMM method under the joint sparsity setting to solve the regularized l2,1-norm problem for a number of samples of the degraded radiation pattern of the HAAwBE rather than computing its array factor, which requires significant and complex mathematical computation. The proposed ADMM technique under the joint sparsity setting allows for minimizing the cost function of the problem with respect to both model parameters and variable vectors. They have further increased accuracy and stability of the performance of the HAAwBE in the two problems of fault detection and DoA estimation by deploying three different optimization methods: LS-SVM, NN-RBF, and NN-MLP, and compared to each other.

Read their article here: https://ieeexplore.ieee.org/document/10473162

This paper is featured in the Special Section on Advanced Beam-Forming Antennas for Beyond 5G and 6G

[2-D Ray-Tracing Model for Multilayer Dielectric Dome Arrays With Inner Reflections]

Maria Pubill-Font, Francisco Mesa, Astrid Algaba-Brazález, Sarah Clendinning, Martin Johansson and Oscar Quevedo-Teruel present a streamlined implementation of ray tracing for fast and efficient numerical analysis of the far-field radiation performance of 2D multilayer dielectric lenses combined with phased arrays. Unlike commercial physical-optical methods, the proposed ray-tracing method is capable of computing the effects of internal reflections in the dome in a multilayer configuration. In addition, the method estimates the absorption losses as a result of the Joule effect.

Read their article here: https://ieeexplore.ieee.org/document/10433065/

This paper is featured in the Special Section on Advanced Beam-Forming Antennas for Beyond 5G and 6G

[Physical Optics Applied to Parallel-Plate Lens Antennas]

Francisco Mesa, Mingzheng Chen, Pilar Castillo-Tapia and Oscar Quevedo-Teruel use the Physical Optics (PO) method to derive simplified expressions to compute the radiation electric fields of planar graded-index and geodesic lenses based on a parallel-plate waveguide (PPW) implementation. If the PO method is combined with ray-tracing (RT) techniques, the resulting RT-PO procedure is capable of computing radiation patterns and gain of the PPW-based lens antennas when their apertures have a general shape and the electric field is vertically polarized. The RT-PO method is validated by comparing it with the full-wave simulation results of the commercial software ANSYS HFSS for three application cases.

Read their article here: https://ieeexplore.ieee.org/document/10374222/

This paper is featured in the Special Section on Advanced Beam-Forming Antennas for Beyond 5G and 6G

Wen-Qiang Deng, H. Zhu, Yu-Xuan Xie, Zhengji Xu and Shu-Yan Zhu propose a novel approach that optimizes reference phases and transmission magnitudes at multiple frequencies assisting with deep learning method to design an ultra-wideband mm-wave circularly polarization antenna. The first neural network intelligently provides the required geometric parameters of the unit cells, while the second neural network validates the phase shifts and predicts the transmission magnitudes based on inputs from the first neural network. The particle swarm optimization (PSO) algorithm is also utilized to optimizes the reference phases at multiple frequencies to minimize the matching errors. To validate the design, a 3-D printed compact CP antenna is fabricated and measured.

Read their article “Design and Optimization of an Ultra-Wideband Millimeter-Wave Circularly Polarized Metalens Antenna With Deep Learning Method” here: https://ieeexplore.ieee.org/document/10443332/

This paper is featured in the Special Section on Advanced Beam-Forming Antennas for Beyond 5G and 6G

[A 3-D Printed Ultra-Wideband Achromatic Metalens Antenna]

Yu-Xuan Xie, Geng-Bo Wu, Wen-Qiang Deng, Shu-Yan Zhu and Chi Hou Chan propose a millimeter-wave achromatic metalens antenna using three-dimensional (3D) printing technology to reduce the dispersion effect and enlarge its bandwidth. The proposed ultra-wideband achromatic metalens antenna consists of a convex-liked metalens (VLM) and a concave-liked metalens (CLM) integrated as a metalens group. The VLM is designed on the basis of dielectric posts with different heights. The calculated transmission phase (from 0 to 2π ) of VLM can be realized by changing the height of dielectric posts.

Read their article here: https://ieeexplore.ieee.org/document/10184275/

This paper is featured in the Special Section on Advanced Beam-Forming Antennas for Beyond 5G and 6G

[Compact Multi-Beamforming Networks Based on Generalized Joined Coupler Matrix With Flexible Beam Angles and Low Sidelobe Levels]

Yang Xu, He Zhu and Y. Jay Guo propose a design of generalized joined coupler (GJC) matrix as a multibeam feeding network using planar circuits and is verified experimentally. The GJC matrix design is built based on a mixture of one-section and two-section branch-line couplers, which are able to realize a wide range of coupling coefficients. A thorough investigation from theoretical analysis to electromagnetic modeling is conducted on one-section and two-section branch-line couplers, and a general design guideline is given for choosing the appropriate type and dimensions for each coupler in a GJC matrix. Then, two types of BFN using microstrip line working at 5 GHz and stripline working at 12 GHz are designed, fabricated and measured, respectively.

Read their article here: https://ieeexplore.ieee.org/document/10328820

This paper is featured in the Special Section on Advanced Beam-Forming Antennas for Beyond 5G and 6G

[Wide-Angle Beam Scanning Phased Array Antennas: A Review]

Ming Li, Shu-Lin Chen, Yanhui Liu and Y. Jay Guo investigate and discuss several challenges that hinder wide-angle beam scanning (WABS) for conventional phased array antennas (PAAs), including the strong mutual coupling, narrow beamwidth of the element antenna, etc. We then review and summarize a variety of innovative techniques to overcome these challenges. Subsequently, we discuss and analyze potential research gaps of WABS PAAs for future emerging applications.

Read their article here: https://ieeexplore.ieee.org/document/10186023/

This paper is featured in the Special Section on Advanced Beam-Forming Antennas for Beyond 5G and 6G

Special Section on Advanced Beam-Forming Antennas for Beyond 5G and 6G is available now!

We would like to thank Guest Editors Shu-Lin Chen, Dongze Zheng, Geng-Bo Wu, Y Jay Guo, Ke Wu, Chi Hou Chan for their time and contributions. The special section features 11 articles and can be viewed here:

https://ieeexplore.ieee.org/xpl/topics.jsp?punumber=8566058&refinements=SpecialSection:Advanced%20Beam-Forming%20Antennas%20for%20Beyond%205G%20and%206G

Shih-Yuan Chen and Chi-Lun Lin proposes a novel approach for human activity recognition using Wi-Fi signals. Traditional methods for signal processing are avoided by converting the ratio of channel state information from antenna pairs into images. These images are then processed using a convolutional neural network to detect movements related to diseases in a large dataset. The experiments utilize a laptop PC with Intel Wi-Fi Link 5300 and a receiver equipped with three external 12 dB omnidirectional antennas in the 2.4 GHz band and cover various daily activities. The proposed method has demonstrated remarkable accuracy, with an average recognition rate of 93.8% in validation. It also showcased a consistent accuracy range of 91.9% to 95.2% in generalization tests, proving its effectiveness in different environments, with various individuals, and under assorted Wi-Fi configurations.

Read their article “Wi-Fi-Based Human Activity Recognition for Continuous, Whole-Room Monitoring of Motor Functions in Parkinson’s Disease” here: https://ieeexplore.ieee.org/document/10508196

Ehsan Rahmati, Pascal Burasa, Elham Baladi, Mohammad S. Sharawi present a completely embedded, planar, dual-element dielectric based antenna directly fed by a substrate integrated insulated guide within the same layer in Sub-THz band. A dielectric layer is employed to make the structure stable. The proposed structure is compatible with the standard planar millimeter-wave and terahertz manufacturing technologies. To minimize the reflection loss, matching air holes inside the guiding channel of the waveguide and air holes with a smaller perforation radius surrounding the antenna are created. The proposed compact antenna, which has been successfully tested, covers the frequency range of 234.5-278.1 GHz with a measured impedance bandwidth of 17.01%, a proper simulated average radiation efficiency of 93.6%, and a maximum gain as well as average gain of 16.08 dBi and 12.56 dBi from measurement results, respectively.

Read their article “Fully Embedded Dual-Element Dielectric-Based Antenna for Sub- and Terahertz Applications” here: https://ieeexplore.ieee.org/document/10507206

[Call for Paper]
Special Section on New Optimization Strategies for Synthesizing RF, Microwave, mmWave, and Optical Devices
Guest Editors: Arkaprovo Das, Manushanker Balasubramanian, Douglas H. Werner, Alberto Toccafondi
Submission Deadline: May 31, 2025
More info: https://ieeeaps.org/new-optimization-strategies-for-synthesizing-rf-microwave-mmwave-and-optical-devices

Aims & Scope:
We invite researchers to contribute original papers that describe emerging optimization approaches that advance the start-of-the-art in electromagnetic (EM) and optical device design. The purpose of this special issue is to publish high-quality research papers addressing recent advances in optimization techniques used for synthesizing RF, microwave, mmWave, metamaterials, and optical devices. The scope of exploration within this special journal cluster encompasses a diverse spectrum of potential topics. These range from genetic algorithms (GAs), particle swarm optimization (PSO), covariance matrix adaptation evolution strategy (CMA-ES), derivative-free techniques, gradient-based methods, and beyond. These potential areas of investigation represent just a fraction of the expansive terrain this cluster aims to traverse, inviting contributions that shape the trajectory of powerful optimization algorithms used for synthesizing novel electromagnetic and optical devices.

Potential topics include but are not limited to the following:
-New and innovative optimization algorithms with an application focus on RF, mmWave, microwave antennas and optical systems
-Comparative analysis, computational investigation, convergence studies, etc. for different optimization techniques used for novel electromagnetic device synthesis
-Gradient computation techniques such as adjoint-based methods, Automatic Differentiation, etc.
-Optimization methods of interest include but are not limited to: Genetic Algorithm (GA), Particle Swarm Optimization (PSO), Covariance Matrix Adaptation Evolution Strategy (CMA-ES), Multi-Objective Lazy Ant Colony Optimization (MOLACO), Wind Driven Optimization (WDO), Topology Optimization (TO), etc.
-State-of-the-art review articles within the aims and scope of application


and multi-objective optimization


and local optimizers

New Optimization Strategies for Synthesizing RF, Microwave, mmWave, ... Download Call for Papers (PDF) Submission Deadline: May 31, 2025 Aims & Scope: Recently, there has been a significant interest in performing holistic design of microwave and optical systems driven by...

Johannes M. Eckhardt, Tobias Doeker and Thomas Kürner present comprehensive double-directional channel measurements with time-domain channel sounding at 300 GHz that characterize the channel of wireless links in a data center. The channels are classified into three scenario-dependent use cases and are individually analyzed providing channel parameters as a function of the required signal-to-noise ratio of the prospective communication system. The spatial and temporal analysis of the channel reveals relevant propagation effects such as the influence of scattering and derives relations between the channel parameters of the propagation and the radio channel.

Read their article “Channel Measurements at 300 GHz for Low Terahertz Links in a Data Center” here: https://ieeexplore.ieee.org/document/10506244

Mohammad Hossein Zadeh, Marina Barbiroli and Franco Fuschini
harnesses the power of Machine Learning to model propagation markers like path loss, shadowing, and delay spread in the industrial environment in this article. By employing Machine Learning techniques, the objective is to achieve flexibility and adaptability in modeling, enabling the system to effectively generalize across diverse industrial scenarios. The proposed model relies on a combination of predictive algorithms, including a linear regression model and a Multi-Layer Perceptron, working collaboratively to model the relationship between the considered propagation markers and input features like frequency and machine size, spacing, and density. Results are in fair overall agreement with previous studies and highlight some trends about the sensitivity of the propagation parameters to the considered input features.

Read their article “A Machine Learning Approach to Wireless Propagation Modeling in Industrial Environment” here: https://ieeexplore.ieee.org/document/10506246

[Call for Papers]
Special Section on Metasurface-related structures for wireless energy harvesting and WPT applications
Guest Editors: Nasimuddin, Abdulrahman Amer, Boon-Chong Seet, Rajkishor Kumar, Merih Palandoken, Alireza Ghaneizadeh
Submission Deadline: October 31, 2025
More info: https://ieeeaps.org/metasurface-related-structures-for-wireless-energy-harvesting-and-wpt-applications

Aims & Scope:
A metasurface is an artificial material composed of an array of unit cell structures. Their thin, low-profile, and cost-effective characteristics have facilitated the creation of numerous innovative EM functions and devices, such as metasurface-inspired antennas, metasurface superstrates, and metalenses. Electromagnetic waves propagate differently in a metasurface compared to a homogeneous medium, exhibiting three unique properties: extremely short wavelength, abrupt phase change, and chromatic dispersion. These properties distinguish wave propagation in metasurfaces from that in natural materials and traditional metamaterials. Metasurface-based RFEHs/WEHs have emerged as a promising solution to meet the growing demand for efficient and sustainable energy sources across various applications. These engineered structures, composed of subwavelength meta-atoms, exhibit unique electromagnetic properties that can enhance the performance of RFEH devices. The ongoing research and development in this field are opening new avenues for the design of advanced EM devices. This special section invites novel and unpublished works on metasurface/metamaterial-related antenna designs for RFEH/WEH and WPT applications.

Potential topics include but are not limited to the following:
-Modeling and characterization of antennas for harvesting applications.
-3-D Antennas for wireless energy harvesting/power transfer systems.
-Designing of high-efficiency and low-powered rectifier circuits.
-Higher-order harmonic attenuating bandpass filter designs.
-New design topologies for high-performance rectenna systems.
-Miniaturized array configurations and beam-steering topologies for high gain and efficient rectenna systems.
-Flexible and wearable rectenna system for lightweight and portable wireless sensor networks.
-Compact Metamaterial/Metasurface designs for performance enhancement of rectenna systems.
-Semiconductor devices for energy harvesting and power transfer applications.
-Multi-layered strategy for energy harvesting system designs.


-basedAntennaArray

-based rectennas

-beam power transfer systems

combining structures
combining structures

Artificial Intelligent Technology for Tunable Terahertz and Millimet... Download Call for Papers (PDF) Submission Deadline: January 31, 2025 Aims & Scope: The millimetre-wave, sub-terahertz (THz) and THz frequency ranges, especially from 30 GHz to 10 THz, are under expon...

Abdul Jabbar, Mostafa Elsayed, Jalil Ur Rehman Kazim, Zhibo Pang, Julien Le Kernec, Muhammad Ali Imran, Qammer H. Abbasi and Masood Ur-Rehman present the complete design of a dynamic metasurface antenna (DMA) array at the 60 GHz millimeter-wave (mmWave) industrial, scientific, and medical (ISM) band. First, a novel complementary electric inductive-capacitive (CELC) metamaterial element (unlike conventional rectangular CELC) is designed to resonate around 60.5 GHz. The proposed CELC meta-element in its resonance state manifests dispersive characteristics and exhibits significant left-handed metamaterial properties such as negative group refractive index, negative effective permittivity, and negative group velocity, which are thoroughly elucidated.

Read their article “60 GHz Programmable Dynamic Metasurface Antenna (DMA) for Next-Generation Communication, Sensing, and Imaging Applications: From Concept to Prototype” here: https://ieeexplore.ieee.org/document/10494997

Photodiodes

Koushik Dutta, Mobayode O. Akinsolu, Puneet Kumar Mishra, Bo Liu and Debatosh Guha explore machine learning (ML)-assisted antenna design techniques aiming to improve and optimize its major radiation parameters over the maximum achievable operating bandwidth. A state-of-the-art method, e.g., parallel surrogate model-assisted hybrid differential evolution for antenna synthesis (PSADEA) has been exercised upon a reference ORCA geometry revealing a fascinating outcome. This modifies the shape of the cavity which was not predicted by EM-based analysis as well as promising significant improvement in its radiation properties.

Read their article “Application of Machine Learning-Assisted Global Optimization for Improvement in Design and Performance of Open Resonant Cavity Antenna” here: https://ieeexplore.ieee.org/document/10492853