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Related papers: Critical Near-Field Impedance Matrices

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The adoption of large-scale antenna arrays at high-frequency bands is widely envisioned in the beyond 5G wireless networks. This leads to the near-field regime where the wavefront is no longer planar but spherical, bringing new…

Signal Processing · Electrical Eng. & Systems 2023-06-28 Ang Chen , Li Chen , Yunfei Chen , Changsheng You , Guo Wei , F. Richard Yu

The advent of massive multiple-input multiple-output (MIMO) technology has provided new opportunities for capacity improvement via strategic antenna deployment, especially when the near-field effect is pronounced due to antenna…

Information Theory · Computer Science 2026-04-09 Shicong Liu , Xianghao Yu , Jie Xu , Rui Zhang

Wireless communications in the millimeter wave (mmWave) and terahertz (THz) spectrum allow harnessing large frequency bands, thus achieving ultra-high data rates. However, the inherently short wavelengths of mmWave and THz signals lead to…

Signal Processing · Electrical Eng. & Systems 2026-05-06 Peng Zhang , Vitaly Petrov , Emil Björnson

An exact method that analytically provides transfer matrices in finite networks of quasicrystalline approximants of any dimensionality is discussed. We use these matrices in two ways: a) to exactly determine the band structure of an…

Condensed Matter · Physics 2016-08-31 K. Moulopoulos , S. Roche

High impedance connecting links and cables are modeled at low frequency in terms of their impedance to ground and to neigbouring connecting links. The impedance is usually considered to be the parallel combination of a resistance and a…

Instrumentation and Detectors · Physics 2013-07-18 Andrea Giachero , Claudio Gotti , Matteo Maino , Gianluigi Pessina

Techniques have been proposed to estimate unknown antenna impedance due to time-varying near-field loading conditions at multiple-input single-output (MISO) receivers. However, it remains unclear when a change occurs and impedance…

Information Theory · Computer Science 2022-11-08 Shaohan Wu

Antenna behaviors such as mutual coupling, near-field propagation, and polarization cannot be neglected in signal and channel models for wireless communication. We present an electromagnetic-based array manifold that accounts for several…

Signal Processing · Electrical Eng. & Systems 2023-11-09 Miguel R. Castellanos , Robert W. Heath

THz photoconductive antennas are among the most popular devices for THz wave generation and detection. A novel and accurate circuit is proposed to model the performance of such antennas, especially those which are frequency dependant. The…

Applied Physics · Physics 2019-03-06 Fatemeh aghili , Ali Mahjoori

The space of complete orthonormal frames in Euclidean space is not path connected. In fact it has exactly two path components, containing respectively the coordinate frame of n standard coordinates and the frame with two coordinates…

Functional Analysis · Mathematics 2020-09-08 Jon A. Sjogren

Future sixth-generation (6G) networks are envisioned to provide both sensing and communications functionalities by using densely deployed base stations (BSs) with massive antennas operating in millimeter wave (mmWave) and terahertz (THz).…

Information Theory · Computer Science 2023-08-16 Haocheng Hua , Jie Xu

Modern antenna design for communication systems revolves around two extremes: devices, where only a small region is dedicated to antenna design, and base stations, where design space is not shared with other components. Both imply different…

Signal Processing · Electrical Eng. & Systems 2022-11-16 Casimir Ehrenborg , Mats Gustafsson

We report microwave impedance measurements of a superconductor-semiconductor hybrid nanowire device with three terminals (3T). Our technique makes use of transmission line resonators to acquire the nine complex scattering matrix parameters…

Mesoscale and Nanoscale Physics · Physics 2022-07-27 B. Harlech-Jones , S. J. Waddy , J. D. S. Witt , D. Govender , L. Casparis , E. Martinez , R. Kallaher , S. Gronin , G. Gardner , M. J. Manfra , D. J. Reilly

This paper examines the number of communication modes, that is, the degrees of freedom (DoF) in a wireless line-of-sight channel comprising a small continuous linear intelligent antenna array in the near field of a large one. The framework…

Information Theory · Computer Science 2025-07-17 Athanasios G. Kanatas , Harris K. Armeniakos , Harpreet S. Dhillon , Marco Di Renzo

Impedance tuning has shown promise to maximize output power, gain, or efficiency for transmitter amplifier devices in changing frequency or array environments. Using impedance tuning in phased-array elements, however, has a significant and…

Instrumentation and Detectors · Physics 2026-02-19 Charles Baylis , Adam Goad , Trevor Van Hoosier , Austin Egbert , Robert J. Marks

The accuracy of two equivalent antenna representations, near-field sources and far-field sources, are evaluated for an antenna installed on a simplified platform in a series of case studies using different configurations of equivalent…

Classical Physics · Physics 2018-08-15 Johan Malmström , Henrik Holter , B. L. G. Jonsson

The open problem of calculating the limiting spectrum (or its Shannon transform) of increasingly large random Hermitian finite-band matrices is described. In general, these matrices include a finite number of non-zero diagonals around their…

Information Theory · Computer Science 2008-05-13 Oren Somekh , Osvalso Simeone , Benjamin M. Zaidel , H. Vincent Poor , Shlomo Shamai

Movable antennas (MAs) show great promise for enhancing the sensing capabilities of future sixth-generation (6G) networks. With the growing prevalence of near-field propagation at ultra-high frequencies, this paper focuses on the…

Signal Processing · Electrical Eng. & Systems 2025-04-08 Yushen Wang , Weidong Mei , Xin Wei , Boyu Ning , Zhi Chen

The active impedance is a fundamental parameter for characterizing the behavior of large, uniform phased array antennas. However, its conventional calculation via the mutual impedance matrix (or the scattering matrix) offers limited…

Instrumentation and Methods for Astrophysics · Physics 2026-04-10 M. Deng , J. Wu

In colocated compressive sensing MIMO radar, the measurement matrix is specified by antenna placement. To guarantee an acceptable recovery performance, this measurement matrix should satisfy certain properties, e.g., a small coherence.…

Information Theory · Computer Science 2022-10-25 Bastian Eisele , Ali Bereyhi , Ingrid Ullmann , Ralf Müller

Pinching-antenna systems have recently emerged as a promising solution for enhancing coverage in high-frequency wireless communications by guiding signals through dielectric waveguides and radiating them via position-adjustable antennas.…

Information Theory · Computer Science 2026-02-25 Hao Feng , Ming Zeng , Ebrahim Bedeer , Xingwang Li , Octavia A. Dobre , Zhiguo Ding