Article
Engineering, Electrical & Electronic
Ruben F. M. Delgado Castillo, Ruyu Ma, Nader Behdad
Summary: The paper introduces a platform-based, electrically small antenna operating in the high-frequency band with switchable directional radiation patterns. This antenna is capable of generating cardioid-shaped radiation patterns oriented towards different directions of the vehicle, with front-to-back ratios better than 15 dB.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2021)
Article
Engineering, Electrical & Electronic
Edward Slevin, Morris B. Cohen, Nathan Opalinski, Lee Thompson, Mark Golkowski
Summary: This article introduces a new approach to transmitting broadband signals from electrically small antennas, overcoming the limitations of traditional antennas. The proposed technique allows for a wider operational bandwidth and is particularly useful for generating very-low-frequency/low-frequency waves, suitable for long-range and underwater communication.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2022)
Article
Engineering, Electrical & Electronic
Ming-Chun Tang, Qingli Lin, Mei Li, Richard W. Ziolkowski
Summary: The presented antenna is a specially designed system that can switch between four different polarization states, exhibiting very stable radiation performance.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2021)
Article
Engineering, Electrical & Electronic
Yanyang Wang, Sen Yan
Summary: The proposed electrically small 3-D antenna utilizes an H-shaped inductive coupling element to feed the antenna, resulting in the generation of a magnetic dipole and a pair of short electric dipoles after being wrapped in cylindrical foam. By combining orthogonal complementary dipoles with the same radiation intensity and quadrature phase difference, a quasi-isotropic radiation pattern is obtained.
IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS
(2021)
Article
Engineering, Electrical & Electronic
Wei Gu, Kevin Luong, Zhi Yao, Han Cui, Yuanxun Ethan Wang
Summary: Utilizing ferromagnetic resonance of thin-film ferrites can improve the radiation efficiency and input impedance matching of electrically small antennas simultaneously. Experimental results of a prototype with a thin-film yttrium-iron-garnet (YIG) core match well with simulation results, demonstrating the efficacy and significance of this concept. Broadband equivalent circuit models are effective in predicting the input impedance and radiation efficiency of FMR-enhanced ESAs at a precision comparable with full-wave simulations.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2021)
Article
Engineering, Electrical & Electronic
Marwan Jadid, Christophe Delaveaud, Serge Bories, Anthony Bellion
Summary: This letter presents a small antenna radiation efficiency measurement method based on the antenna quality factor. It modifies the original Q factor method by considering the loss Q factor of the antenna instead of the radiation Q factor. The method is verified for two types of antennas operating at different frequencies, and it shows high accuracy compared to the conventional Wheeler cap method.
IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS
(2023)
Article
Engineering, Electrical & Electronic
Alexander J. Angilella, Nichole K. Davis, Ian T. McMichael
Summary: This study explores the use of piezocomposite materials for impedance matching in electrically small strain antennas and proposes a methodology for achieving impedance matching without the need for an external network. The study also reveals that the radiation resistance of piezoelectric strain antennas is much smaller than that of similarly sized electric dipole antennas.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2022)
Article
Engineering, Electrical & Electronic
Adam Narbudowicz, Abel Zandamela, Nicola Marchetti, Max J. Ammann
Summary: This letter proposes a compact and energy-efficient directional modulation scheme for small and power constrained devices. It uses a uniform circular array of monopole antennas and does not generate additional artificial noise to interfere with other systems.
IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS
(2022)
Article
Engineering, Electrical & Electronic
Zhentian Wu, Ming-Chun Tang, Richard W. Ziolkowski
Summary: This article investigates an electrically small, planar, frequency-agile, beam-switchable Huygens dipole antenna, which utilizes varactor diodes to tune its operating frequency and switch its main beam direction for two independent endfire radiating states. The antenna demonstrates a 5% frequency-agile fractional impedance bandwidth in both states, with high radiation efficiency, peak realized gain, front-to-back ratio, and stable radiation patterns over the frequency-agile range.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2021)
Article
Engineering, Electrical & Electronic
Zahra Esmati, David A. Powell, Michael C. Skipper, Michael D. Abdalla, J. Scott Tyo
Summary: This article presents a fully parameterized circuit model for array antennas, which relates antenna performance and field coupling to the physical parameters of the elements. The simplified model can be used as a surrogate for full-wave modeling during the initial optimization steps in array design. The model considers mutual coupling between array elements through the feeding network and free space, and provides excellent agreement with the scattering parameters calculated by the full-wave numerical model.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2023)
Article
Engineering, Electrical & Electronic
Alex Bouvy, Nader Behdad
Summary: This article analyzed two primary bandwidth considerations for electrically small, platform-based antennas in the HF band: coupling element (CE) location and CE design. It found that both CE type and placement significantly impact the impedance bandwidth of the antenna. Experimental characterization of scaled models showed good agreement with simulations.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2021)
Article
Engineering, Electrical & Electronic
Shuxuan Liu, Zhan Wang, Yuandan Dong
Summary: This letter presents a novel design of an electrically small, circularly polarized capacitively loaded loop-based antenna for UHF RFID applications. The proposed antenna exhibits excellent overall performance, including easy fabrication, good bandwidth, high gain and efficiency, and wide beamwidth.
IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS
(2022)
Article
Engineering, Electrical & Electronic
Ming-Chun Tang, Piao Guo, Dajiang Li, Kun-Zhi Hu, Mei Li, Richard W. Ziolkowski
Summary: This paper presents the design of vertically polarized, omnidirectional- and endfire-radiating, bandwidth-enhanced, high-efficiency electrically small monopole filtennas. The performance of the filtennas is achieved by combining a coax-fed top-hat loaded monopole with two hybrid quarter-wavelength open-end stubs and a shorting post. The measured results confirm the efficacy of both filtenna designs.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2022)
Article
Engineering, Electrical & Electronic
Nathan Strachen, Elham Mohammadi, John Booske, Nader Behdad
Summary: This study presents the design and experimental demonstration of an active electrically small antenna capable of transmission over the entire HF band. The antenna consists of a 2-m long dipole integrated with a class-AB push-pull amplifier. Experimental results show stable, ultra-wideband operation and total efficiency improvements of over 15 dB compared to passive matching scenarios.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2022)
Article
Chemistry, Physical
Kabir Hossain, Thennarasan Sabapathy, Muzammil Jusoh, Ping Jack Soh, Mohd Haizal Jamaluddin, Samir Salem Al-Bawri, Mohamed Nasrun Osman, R. Badlishah Ahmad, Hasliza A. Rahim, Mohd Najib Mohd Yasin, Nitin Saluja
Summary: This study presents an electrically tunable textile-based metamaterial (MTM) with left-handed characteristics and negative permittivity and permeability within specific frequency ranges. The proposed MTM unit cell and arrays were independently studied and experimentally verified, showing tunable transmission coefficient and dynamic operation potential for microwave wearable applications.
Article
Engineering, Electrical & Electronic
Ting Shi, Ming-Chun Tang, Ruolei Chai, Richard W. Ziolkowski
Summary: This article demonstrates an electrically small directive antenna (ESDA) that excites a set of multipoles through a specially engineered port. The experimental results show that the antenna has high radiation efficiency and impedance matching, and achieves supergain. At the resonance frequency of 814 MHz, the antenna has a peak directivity of 6.71 dBi and a peak realized gain of 6.31 dBi.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2022)
Article
Engineering, Electrical & Electronic
Zhentian Wu, Ming-Chun Tang, Richard W. Ziolkowski
Summary: This paper presents an electrically small, full-duplex Huygens dipole filtenna realized through a dense array of HDF elements, which achieves good out-of-band rejection performance and high isolation levels.
MICROWAVE AND OPTICAL TECHNOLOGY LETTERS
(2022)
Review
Materials Science, Multidisciplinary
David A. Katzmarek, Aiswarya Pradeepkumar, Richard W. Ziolkowski, Francesca Iacopi
Summary: This review provides an in-depth analysis of current trends, challenges, and prospects within the research areas of generating, manipulating, and detecting electromagnetic fields using graphene-based devices that operate from microwave to terahertz frequencies.
Article
Engineering, Electrical & Electronic
Yubo Wen, Pei-Yuan Qin, Geng-Ming Wei, Richard W. Ziolkowski
Summary: In this study, a multiport circular array of endfire Yagi-Uda monopoles with full beam coverage of the azimuth plane is developed. The issue of a vertical monopole antenna radiating an elevated beam on a finite-sized horizontal ground plane is investigated. By inserting resonant structures, such as slots, into the ground plane to redirect the radiated beam back to the horizontal direction, this effect can be mitigated.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2022)
Article
Engineering, Electrical & Electronic
David A. A. Katzmarek, Yang Yang, Mohammad B. B. Ghasemian, Kourosh Kalantar-Zadeh, Richard W. W. Ziolkowski, Francesca Iacopi
Summary: The properties of epitaxial graphene for radio frequency (RF) applications are investigated. Metal coplanar waveguides (CPWs) are fabricated to evaluate the frequency-dependent behavior of the graphene's sheet resistance. The quality of the metal contact with graphene and the influence of small-scale discontinuities are important factors in the RF spectrum.
IEEE ELECTRON DEVICE LETTERS
(2023)
Article
Engineering, Electrical & Electronic
Shu-Lin Chen, Richard W. Ziolkowski, Bevan Jones, Y. Jay Guo
Summary: This article presents a substrate-integrated toroidal waveguide-based leaky-wave antenna (LWA) that uses different-shaped radiators to radiate beams with different polarizations. The performance of the system is confirmed through testing.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2022)
Article
Engineering, Electrical & Electronic
Wei Lin, Richard W. Ziolkowski
Summary: This paper presents an A-band Huygens antenna array with high aperture efficiency and low sidelobe levels, suitable for 5G millimeter-wave applications. The array consists of innovative Huygens subarrays formed by open rectangular waveguides. The full broadside-radiating array achieves an aperture efficiency up to 97.5% and sidelobe and backlobe levels less than -20 dB, with an impedance bandwidth of 26.7-29.65 GHz and a peak realized aperture efficiency of 82%. A prototype of the array was fabricated and tested, showing good agreement with simulation results.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2023)
Article
Engineering, Electrical & Electronic
Qingli Lin, Ming-Chun Tang, Mei Li, Richard W. Ziolkowski
Summary: This article reports the design of a wideband, circularly polarized electrically small antenna with two axial ratio poles. The design includes a specially engineered driven dipole, a resonant parasitic crossed Egyptian axe dipole, and an inductive grid-array metasurface. The measured results agree well with simulated ones, achieving a wide axial ratio bandwidth by pressing the two poles close together.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2023)
Article
Engineering, Electrical & Electronic
Richard W. Ziolkowski
Summary: There is a demand for highly directive antenna systems for space-limited Internet-of-Things devices and NextG applications. Compact high-frequency high-directivity alternatives to phased arrays are desired. This study presents the simulated performance characteristics of compact unidirectional mixed-multipole antennas (UMMAs) based on dipole and quadrupole mixtures, showing their high directivities and attractive radiation efficiencies.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2023)
Proceedings Paper
Engineering, Electrical & Electronic
Wei Lin, Richard W. Ziolkowski
Summary: This paper presents a Ka-band Huygens antenna array with high realized aperture efficiency for 5G wireless applications. The array is formed by a 1x2 Huygens sub-array consisting of open waveguides and orthogonally-oriented dipole plates, which create two pairs of Huygens electric and magnetic radiators. A reflector is used to mitigate scattered fields and improve aperture efficiency. The array shows a wide impedance bandwidth and achieved high gain and aperture efficiency within this bandwidth.
2022 INTERNATIONAL SYMPOSIUM ON ANTENNAS AND PROPAGATION (ISAP)
(2022)
Proceedings Paper
Engineering, Electrical & Electronic
Shu-Lin Chen, Richard W. Ziolkowski, Bevan Jones, Y. Jay Guo
Summary: Leaky-wave antennas (LWAs) are promising for future wireless systems that demand compactness and seamless integration. However, traditional LWAs require a termination load to absorb the power remaining in their waveguide beyond the radiating elements, leading to decreased gain and efficiency. In this work, a novel closed-path toroidal-waveguide based LWA is developed to address this issue by achieving power recycling and improving antenna performance.
2022 INTERNATIONAL SYMPOSIUM ON ANTENNAS AND PROPAGATION (ISAP)
(2022)
Proceedings Paper
Engineering, Electrical & Electronic
Qingli Lin, Ming-Chun Tang, Richard W. Ziolkowski
Summary: This paper proposes a compact, wideband, circularly polarized dipole antenna, which consists of a crossed Egyptian axe dipole antenna and an inductive parasitic grid array metasurface. The antenna achieves wideband circularly polarized radiation through the collaboration between the grid array structure and the EAD antenna.
2022 IEEE-APS TOPICAL CONFERENCE ON ANTENNAS AND PROPAGATION IN WIRELESS COMMUNICATIONS (IEEE APWC)
(2022)
Proceedings Paper
Engineering, Electrical & Electronic
Yaqing Yu, Ming-Chun Tang, Da Yi, Dingmou Hong, Ting Shi, Richard W. Ziolkowski
Summary: This paper presents a near-field resonant parasitic active electrically small transmitting antenna, which combines an electrically small antenna with an operational amplifier. The antenna achieves a higher effective gain and gain-bandwidth product compared to its passive counterpart.
2022 16TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION (EUCAP)
(2022)
Proceedings Paper
Engineering, Electrical & Electronic
Wei Lin, Richard W. Ziolkowski
Summary: This article introduces the application of ultrathin metamaterial-inspired Huygens dipole antenna and rectenna arrays for wireless power transfer in IoT applications. The design and experimental verification of the antenna structures and arrays based on metamaterials are presented.
2022 16TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION (EUCAP)
(2022)
Article
Engineering, Electrical & Electronic
Richard W. Ziolkowski
Summary: Multipole expansions play a fundamental role in analyzing the electromagnetic fields. This article provides an overview of the recent surge in interest in multipole sources and their fields, discussing their practical applications in achieving useful radiated and scattered fields with high directivities.
IEEE OPEN JOURNAL OF ANTENNAS AND PROPAGATION
(2022)
