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Related papers: Critical Near-Field Impedance Matrices

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This study establishes a unified framework for interpreting dynamic capacitive responses in InGaN-based light-emitting diodes (LEDs) through forward-bias capacitance-voltage-frequency spectroscopy. A hybrid impedance model integrating…

Small volume, finite conductivity and high frequencies are major imperatives in the design of communications infrastructure. The radiation efficiency $\eta_r$ impacts on the optimal gain, quality factor, and bandwidth. The current…

Classical Physics · Physics 2018-06-13 Morteza Shahpari , David V. Thiel

We study the Ising model on the triangular lattice with nearest-neighbor couplings $K_{\rm nn}$, next-nearest-neighbor couplings $K_{\rm nnn}>0$, and a magnetic field $H$. This work is done by means of finite-size scaling of numerical…

Computational Physics · Physics 2009-11-10 Xiaofeng Qian , Henk W. J. Bloete

The Antennae galaxies are the closest example of an ongoing major galaxy merger, and thereby represent a unique laboratory for furthering the understanding of the formation of exotic objects (e.g., tidal dwarf galaxies, ultra-luminous X-ray…

Astrophysics · Physics 2009-11-13 Ivo Saviane , Yazan Momany , Gary S. Da Costa , R. Michael Rich , John Hibbard

We study the perfect conductivity problem with closely spaced perfect conductors embedded in a homogeneous matrix where the current-electric field relation is the power law $J=\sigma|E|^{p-2}E$. The gradient of solutions may be arbitrarily…

Analysis of PDEs · Mathematics 2023-11-21 Hongjie Dong , Zhuolun Yang , Hanye Zhu

Due to its significance in terms of wave phenomena a considerable effort has been put into the design of preconditioners for the Helmholtz equation. One option to derive a preconditioner is to apply a multigrid method on a shifted operator.…

Computational Engineering, Finance, and Science · Computer Science 2021-04-06 Daniel Drzisga , Tobias Köppl , Barbara Wohlmuth

The employment of partial zero-forcing (PZF) receivers at the base stations represents an efficient and low-complexity technique for uplink interference management in cellular networks. In this paper, we focus on the performance analysis of…

Information Theory · Computer Science 2016-11-24 Italo Atzeni , Marios Kountouris

We show that for a winding number zero satellite operator $P$ on the knot concordance group, if the axis of $P$ has nontrivial self-pairing under the Blanchfield form of the pattern, then the image of the iteration $P^n$ generates an…

Geometric Topology · Mathematics 2025-03-05 Jae Choon Cha , Taehee Kim

We propose a design strategy for optimizing antenna positions in linear arrays for far-field Direction of Arrival (DoA) estimation of narrow-band sources in collocated MIMO radar. Our methodology allows to consider any spatial constraints…

Signal Processing · Electrical Eng. & Systems 2018-04-24 M. A. González-Huici , D. Mateos-Núñez , C. Greiff , R. Simoni

Modern MIMO communication systems are almost exclusively designed under the assumption of locally plane wavefronts over antenna arrays. This is known as the far-field approximation and is soundly justified at sub-6-GHz frequencies at most…

Information Theory · Computer Science 2023-02-28 Giacomo Bacci , Luca Sanguinetti , Emil Björnson

This paper explores the potential of near-field beamforming (NFBF) in integrated sensing and communication (ISAC) systems with extremely large-scale arrays (XL-arrays). The large-scale antenna arrays increase the possibility of having…

Signal Processing · Electrical Eng. & Systems 2023-08-15 Kaiqian Qu , Shuaishuai Guo , Nasir Saeed

In this paper, performance bounds for the multi-antenna near-field range estimation of extended targets are provided. First, analytic expressions of the ambiguity functions are obtained, emphasising the cooperation between the waveform…

Signal Processing · Electrical Eng. & Systems 2024-07-24 Guillaume Thiran , François De Saint Moulin , Claude Oestges , Luc Vandendorpe

We consider approximating the solution of the Helmholtz exterior Dirichlet problem for a nontrapping obstacle, with boundary data coming from plane-wave incidence, by the solution of the corresponding boundary value problem where the…

Numerical Analysis · Mathematics 2023-06-23 Jeffrey Galkowski , David Lafontaine , Euan A. Spence

We study the approximation of stationary processes by a simple class of purely deterministic signals. This has an analytic counterpart in the approximation of symmetric positive definite Toeplitz matrices by submatrices of finite rank. We…

Probability · Mathematics 2020-09-15 Giorgio Picci , Bin Zhu

This paper addresses the problem of finding an orientation and a minimum radius for directional antennas of a fixed angle placed at the points of a planar set S, that induce a strongly connected communication graph. We consider problem…

Computational Geometry · Computer Science 2010-08-24 Mirela Damian , Robin Flatland

High percentage of voltage harmonics has been observed in transmission networks due to harmonic currents penetrated from the load side amplified by resonant conditions. This requires the use of suitable harmonic filters in transmission…

Systems and Control · Electrical Eng. & Systems 2019-11-19 Behnam Akbari , Farhad Pourtahmasbi , Hossein Mokhtari

Because all microstrip antennas have to be matched to the standard generator impedance or load, the input impedance matching method for antenna is particularly important. In this paper a new methodology in achieving matching impedance of a…

Other Computer Science · Computer Science 2010-06-07 Mahdi Ali , Abdennacer Kachouri , Mounir Samet

A novel quantity for predicting the high-gradient performance of radio frequency accelerating structures is presented. The quantity is motivated, derived and compared with earlier high-gradient limits and experiments. This new method models…

Accelerator Physics · Physics 2022-10-03 Jan Paszkiewicz , Alexej Grudiev , Walter Wuensch

A multiband empirical tight-binding model for group-III-nitride semiconductors with a wurtzite structure has been developed and applied to both bulk systems and embedded quantum dots. As a minimal basis set we assume one s-orbital and three…

Mesoscale and Nanoscale Physics · Physics 2015-05-18 Daniel Mourad , Stefan Barthel , Gerd Czycholl

The approach of metric-affine field theory is to define spacetime as a real oriented 4-manifold equipped with a metric and an affine connection. The 10 independent components of the metric tensor and the 64 connection coefficients are the…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Alastair D. King , Dmitri Vassiliev