Article
Engineering, Electrical & Electronic
Ziheng Ding, Jingfeng Chen, Han Zhou, Xianling Liang, Ronghong Jin
Summary: A phasor beam steering stacked patch antenna is proposed to improve the aperture efficiency of an arced conformal array. By switching the bias states of PIN diodes, the phasor beam steering antenna can achieve phase pattern reconfiguration. The amplitude pattern reconfiguration is also utilized to enhance the contribution of side elements to the gain of the axial beam. A four-element arced conformal array with the phasor beam steering antenna is designed and measured, showing improved gain and aperture efficiency compared to the conventional phase compensation network.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2023)
Editorial Material
Engineering, Electrical & Electronic
Karu Esselle, Ladislau Matekovits, Yang Yang, Dushmantha Thalakotuna, Muhammad Afzal, Maria Kovaleva, Khushboo Singh
Summary: The papers in this special section focus on the latest advancements in applied and analytical research, highlighting innovative materials and methods for beam-steering antenna design, as well as novel approaches for designing and analyzing antennas for the next generation of satellite communication systems.
IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS
(2022)
Article
Engineering, Electrical & Electronic
Jiaxuan Liang, Tingyin Ning, Jiayu Fan, Zhiyong Wu, Min Zhang, Hong Su, Yu-Jia Zeng, Huawei Liang
Summary: The research proposes metallic waveguide transmiarray antennas (MWTAs) capable of generating multibeams with high gain and optional polarized states through simultaneous control of phase and polarization. Experimental results demonstrate promising performance for communication applications in the terahertz and millimeter wave bands.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2021)
Article
Engineering, Electrical & Electronic
Weixu Yang, Ke Chen, Xinyao Luo, Kai Qu, Junming Zhao, Tian Jiang, Yijun Feng
Summary: A novel high-efficiency polarization-selective bifunctional metasurface has been proposed, which can selectively manipulate left-handed and right-handed circularly polarized light. Through numerical simulations and experiments, it has been shown that the proposed metasurface can be applied to high-gain antennas in millimeter-wave communication systems.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2022)
Article
Engineering, Electrical & Electronic
Yujie Zhang, Zixiang Han, Shiwen Tang, Shanpu Shen, Chi-Yuk Chiu, Ross Murch
Summary: This article introduces a novel single-fed horizontally polarized pattern-reconfigurable antenna that is highly capable of generating various radiation patterns. The antenna is able to achieve flexible beam steering and full 3-D space scanning without the use of phase shifters. Experimental and simulation results demonstrate the antenna's performance in different radiation modes, showcasing its high pattern reconfigurability and versatility for sub-6 GHz wireless applications.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2022)
Article
Computer Science, Information Systems
Daeyeong Yoon, Jihyung Kim, Hokeun Shin, Dong-Yeop Na, Yong Bae Park
Summary: This paper proposes a novel algorithm based on ray tracing technique to compute the radiation pattern of a slot array antenna covered with frequency selective surfaces (FSS). By combining the image method and physical optics technique, the proposed algorithm greatly reduces computational resources while providing accurate numerical solutions compared to standard full-wave and conventional high-frequency approaches. The algorithm is particularly well-suited for efficiently dealing with electrically large structures and can advance the existing design process.
Article
Engineering, Electrical & Electronic
Mohammad Reza Safaeian, Leila Yousefi
Summary: This paper proposes a new architecture for developing plasmonic bio-sensors, where sensing is achieved through optical beam steering. Numerical simulation results show that the designed structure has high sensitivity and sufficient output light intensity.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2022)
Article
Engineering, Electrical & Electronic
Mingjiang Teng, Shixing Yu, Na Kou, Zhao Ding, Zhengping Zhang
Summary: This paper presents a mechanical beam steering array antenna with tunable height elements. By controlling the height of each antenna element, arbitrary phase shift values and high-gain beams can be achieved. Experimental results demonstrate the effectiveness of the antenna array in beam scanning and near-field focusing.
IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS
(2022)
Article
Chemistry, Analytical
Dmitry Kozlov, Irina Munina, Pavel Turalchuk, Vitalii Kirillov, Alexey Shitvov, Dmitry Zelenchuk
Summary: A new implementation of a beam-steering transmitarray is proposed based on the tiled array architecture, enabling a wide range of beam steering and beam forming capabilities. Through hard-wired settings and phase modulation patterns, specific transmission characteristics and performance can be achieved. Testing of prototypes of tiled and single-panel transmitarrays show close performance to simulations and minimal impact from fabrication tolerances, indicating great potential for fifth-generation (5G) communication systems.
Article
Engineering, Electrical & Electronic
Xiang Wan, Bai Yang Li, Wen Hao Wang, Zi Ai Huang, Jia Wei Wang, Xu Jie Wang, Qiang Cheng, Tie Jun Cui
Summary: A code-dependent methodology is proposed to simultaneously realize beam shaping and polarization control using binary transmit arrays (BTA). By individually designing binary codes for different unit elements, the radiation pattern and polarization of the synthetic field can be defined. Simulations and measurements have verified that this methodology provides a completely code-dependent mechanism to design radiation patterns and polarizations of BTAs. The methodology has great potential in communication and radar applications.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2023)
Article
Engineering, Electrical & Electronic
Lehu Wen, Steven Gao, Qi Luo, Wei Hu, Benito Sanz-Izquierdo, Chao Wang, Xue-Xia Yang
Summary: A wideband transmitarray (TA) antenna using compact 2-bit filtering unit cells is presented, which features wide bandwidth, compact aperture size, filtering radiation performance, and low cross-polarization levels.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2023)
Article
Engineering, Electrical & Electronic
Seyed Jalil Hosseini, Mohammad Khalaj Amirhosseini
Summary: This article introduces an eight-port planar leaky-wave antenna capable of beam steering at an elevation angle by changing the frequency at eight azimuth angles. The antenna is planar and includes a microstrip parallel plate waveguide embedded with an array of ring slots. Simulation and experimental results are investigated, showing good agreement and confirming the leaky-wave concept. The proposed antenna offers an attractive, simple, and cost-effective solution for beam scanning over the 3-D space.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2022)
Article
Engineering, Electrical & Electronic
Shafaq Kausar, A. U. Kausar, Muhammad Usman Hadi, Hani Mehrpouyan
Summary: This paper presents the design of a high gain multi-beam transmitarray antenna, which is capable of independently steering multiple beams in the azimuth and elevation plane. By using a passive meta-surface, the antenna achieves continuous beam steering by adjusting the phase of the unit cell transmission coefficient. The designed antenna is low cost, robust, and suitable for satellite communication and mm-Wave 5G systems.
AEU-INTERNATIONAL JOURNAL OF ELECTRONICS AND COMMUNICATIONS
(2024)
Article
Engineering, Electrical & Electronic
Ghanshyam Mishra, Satish Kumar Sharma
Summary: The novel Ka-band Butterfly phased array antenna features full-polarization reconfigurability, flexible radiation pattern, and wide-angle beam steering performance. By adjusting the excitation of the ports, different polarizations can be achieved, providing dynamic beamwidth and flexible radiation characteristics.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2021)
Article
Engineering, Electrical & Electronic
Tanzeela Mitha, Maria Pour
Summary: The potential of dynamically steering the null locations in equally spaced linear scanning array antennas using the E-DPCA technique is investigated for the first time in this study. The E-DPCA technique allows for electronic variation of the relative coordinates and element spacing of the array antennas, enabling adaptive null location steering without physical displacement while maintaining the same overall array length. The versatility of the proposed technique is further demonstrated by generating consecutive nulls with a minimum resolution of 1 degree and simultaneously steering the null locations and scanning the main beam.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2023)
Article
Engineering, Electrical & Electronic
Marina Jordao, Daniel Belo, Rafael F. S. Caldeirinha, Arnaldo S. R. Oliveira, Nuno B. Carvalho
Summary: The study aims to present a characterization system for measuring the active reflection coefficient of each port of MIMO antennas when the main beam is steered. A calibrated measurement system using off-the-shelf software defined radio was implemented to extract coefficients when all ports are simultaneously excited. Experimental results for linear and planar MIMO antenna arrays were obtained for various beam directions and the impact of beamforming on antenna elements was assessed and compared to simulated results.
IET MICROWAVES ANTENNAS & PROPAGATION
(2021)
Review
Energy & Fuels
Marina Jordao, Rafael Caldeirinha, Arnaldo S. R. Oliveira, Nuno Borges Carvalho
Summary: This paper provides an extended critical review of validated OTA linearization methods for transmitter antenna arrays in 5G scenarios. The main goal is to determine the most suitable method for specific applications by analyzing and discussing the benefits and disadvantages of each method. The aim is to fill a gap in the scientific literature and assist radio-frequency engineers in implementing OTA digital pre-distortion techniques for MIMO systems.
Article
Engineering, Electrical & Electronic
Nuno Leonor, Stefania Faria, Mario Vala, Rafael F. S. Caldeirinha
Summary: This letter presents a combined model for appropriate radio coverage in mountainous vegetated terrains, and the model was validated through experiments.
IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS
(2022)
Article
Chemistry, Analytical
Tiago Emanuel Oliveira, Joao Ricardo Reis, Rafael Ferreira Silva Caldeirinha
Summary: This paper presents the implementation of a Wireless Sensor Network (WSN) for environmental monitoring (EM). It includes the design and implementation of a multi-sector base station antenna and a reduced form factor antenna for the sensor nodes. The WSN is based on Lopy4 transceivers. Field tests confirm the connectivity between the sensor nodes and the developed WSN base station, achieving a 360 degrees field of view.
Article
Engineering, Electrical & Electronic
Mario Vala, Stefania Faria, Pedro Coimbra, Nuno Leonor, Joao M. Felicio, Carlos A. Fernandes, Carlos Eduardo do Rego da Costa Salema, Rafael F. S. Caldeirinha
Summary: This article studies the fading of radiowaves caused by fire plumes resulting from burning piles of pine needles. It presents a detailed characterization of the impact of fire on excess loss in UHF frequencies, particularly in the L-band, under two different ignition sources. The study used a small-scale fire scenario with a metallic grid covered in pine needle fuel above a gas burner to simulate an underbrush situation. The results demonstrate significant changes in the propagation medium due to the influence of the plume, including deep fades and median excess loss. These findings are important for future work in mission-critical communication networks planning.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2023)
Article
Engineering, Electrical & Electronic
Stefania Faria, Mario Vala, Pedro Coimbra, Nuno Leonor, Joao M. Felicio, Carlos A. Fernandes, Carlos Salema, Rafael F. S. Caldeirinha
Summary: This letter presents measurement results and initial physical modeling of radio wave propagation phenomena in the presence of fire using Pinus pinaster fuel heaps. Small-scale measurement trials at 700 MHz were carried out on a Pinus pinaster fuel bed on fire, and subsequent simulation results of the propagation phenomena behavior were validated using both the fire dynamics simulator and the cold plasma model. Excessive attenuation of up to 1.52 dB was observed in the measured results, which is considered critical considering the small-scale fire scenario with a 1 x 1 m(2) area and 0.6 kg of pine needles.
IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS
(2023)
Article
Engineering, Electrical & Electronic
Nuno R. Leonor, Stefania Faria, Glaucio Ramos, Pedro V. Gonzalez Castellanos, Carlos Rodriguez, Luiz da Silva Mello, Rafael F. S. Caldeirinha
Summary: This article presents a radio propagation model for macrocell coverage predictions in built-up areas. The proposed model combines various individual propagation models to account for the impact of buildings, terrain, and vegetation on signal attenuation. The model's performance was evaluated using measurement results obtained from a campaign conducted in Rio de Janeiro, Brazil.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2022)
Proceedings Paper
Engineering, Electrical & Electronic
Tiago E. Oliveira, Joao R. Reis, Rafael F. S. Caldeirinha
Summary: This paper presents a novel microstrip Quasi-Yagi antenna based on Waning Crescent elements. The antenna utilizes a microstrip dipole as the radiating element and optimized waning crescent shaped elements as reflector and directors. It is designed and optimized to operate in the 2.4 GHz ISM band, catering to the integration in a multi-sector base station antenna configuration for a Wireless Sensing Network (WSN) for environmental monitoring.
2022 3RD URSI ATLANTIC AND ASIA PACIFIC RADIO SCIENCE MEETING (AT-AP-RASC)
(2022)
Proceedings Paper
Engineering, Electrical & Electronic
Stefania Faria, Mario Vala, Nuno Leonor, Joao Felicio, Carlos Fernandes, Carlos Salema, Rafael Caldeirinha
Summary: This paper presents an electrical modelling of radiowave propagation in a fire environment. The modelling was done by designing a small-scale forest with 8 Pinus Pinaster trees using the Fire Dynamics Simulator (FDS). The effects of fire on radiowave propagation were evaluated using the Cold Plasma Model (CPM) and the Transmission Line Method (TLM) for a specific frequency. The paper provides statistical analysis of overall attenuation and important measurements of relative permittivity and refractive index values.
2022 3RD URSI ATLANTIC AND ASIA PACIFIC RADIO SCIENCE MEETING (AT-AP-RASC)
(2022)
Proceedings Paper
Engineering, Electrical & Electronic
Glaucio L. Ramos, Mario Vala, Rafael F. S. Caldeirinha, Nuno Leonor, Luiz da Silva Mello
Summary: This paper applies a simple deconvolution process to retrieve the angle of arrival (AoA) in an environment with metallic poles, mimicking a cluster of scatterers. The experimental results show that the proposed technique is effective in retrieving the AoA and relative power between components, which is crucial for improving propagation models.
2022 16TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION (EUCAP)
(2022)
Proceedings Paper
Engineering, Electrical & Electronic
Bruno Tribovane, Rafael Caldeirinha
Summary: This paper presents the study of a multi-layered timber barrier for enhancing electromagnetic shielding or transparency to radio propagation in road electromagnetic barriers.
2022 16TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION (EUCAP)
(2022)
Proceedings Paper
Engineering, Electrical & Electronic
Stefania Faria, Mario Vala, Nuno Leonor, Joao M. Felicio, Carlos Fernandes, Carlos Salema, Rafael Caldeirinha
Summary: This paper presents the results of a measurement campaign evaluating the impact of forest fires on radiowave propagation. By burning Pinus Pinaster needles as fuel, the paper examines the loss introduced by fire and variations in signal level during transmission.
2022 16TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION (EUCAP)
(2022)
Proceedings Paper
Computer Science, Information Systems
Tiago E. S. Oliveira, Mario Vala, Stefania Faria, Joao R. Reis, Nuno Leonor, Rafael F. S. Caldeirinha
Summary: This paper studies the impact of vegetation and fire on the radiation pattern of a small antenna for a WSN sensor node. Simulations were conducted in four different scenarios to analyze the effects of these factors.
INTERNET OF THINGS: TECHNOLOGY AND APPLICATIONS
(2022)
