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Related papers: Trade-off Between Antenna Efficiency and Q-Factor

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A multiplicity of autonomous terminals simultaneously transmits data streams to a compact array of antennas. The array uses imperfect channel-state information derived from transmitted pilots to extract the individual data streams. The…

Information Theory · Computer Science 2012-05-23 Hien Quoc Ngo , Erik G. Larsson , Thomas L. Marzetta

Though commonly used to calculate Q-factor and fractional bandwidth, the energy stored by radiating systems (antennas) is a subtle and challenging concept that has perplexed researchers for over half a century. Here, the obstacles in…

This paper studies the energy efficiency and sum rate trade-off for coordinated beamforming in multi-cell multi-user multigroup multicast multiple-input single-output systems. We first consider a conventional network energy efficiency…

Information Theory · Computer Science 2018-10-17 Oskari Tervo , Le-Nam Tran , Harri Pennanen , Symeon Chatzinotas , Björn Ottersten , Markku Juntti

In this paper, we derive a number of inequalities which express power-efficiency trade-offs that hold generally for thermodynamic machines operating in non-equilibrium stationary states. One of these inequalities concerns the output power,…

Statistical Mechanics · Physics 2019-09-04 Hadrien Vroylandt , David Lacoste , Gatien Verley

A radio antenna is primarily designed to convert electromagnetic waves into electrical current and vice versa. However, a part of the incident wavefield is scattered due to structural effects andreflection at the antenna's electrical port.…

Applied Physics · Physics 2026-05-21 Julien de Rosny , Youssef Rammal , Ismaïl Ahmed Bouha , François Sarrazin

We consider a dense fading multi-user network with multiple active multi-antenna source-destination pair terminals communicating simultaneously through a large common set of $K$ multi-antenna relay terminals in the full spatial multiplexing…

Information Theory · Computer Science 2016-11-15 Ozgur Oyman , Arogyaswami J. Paulraj

Frequency-selective wireless power transfer provides a feasible route to enable independent actuation and control of multiple untethered robots in a common workspace; however, the scalability remains unquantified, particularly the maximum…

Systems and Control · Electrical Eng. & Systems 2026-04-14 Gabriel Cooper , Xiaolong Liu

In this paper, a new lower bound on spectral efficiency in the low-power wideband regime is derived and utilized to develop an improved estimate of the behavior of spectral efficiency above but in the vicinity of the Shannon limit.

Information Theory · Computer Science 2014-07-10 Richard J. Barton

The next generation wireless systems will face stringent new requirements, including ultra-low latency, high data rates and enhanced reliability. Large Intelligent Surfaces, is one proposed solution that has the potential to solve these…

Signal Processing · Electrical Eng. & Systems 2025-10-16 Lina Tinnerberg , Dumitra Iancu , Ove Edfors , Liang Liu , Juan Vidal Alegría

Efficient micro-resonators simultaneously require a large quality factor $Q$ and a small volume $V$. However, the former is ultimately limited by bending losses, the unavoidable radiation of energy of a wave upon changing direction of…

Optics · Physics 2019-08-07 Nirmalendu Acharyya , Gregory Kozyreff

Channel estimation is challenging in multi-antenna communication systems, because of the large number of parameters to estimate. It is possible to facilitate this task by using a physical model describing the multiple paths constituting the…

Signal Processing · Electrical Eng. & Systems 2018-04-27 Luc Le Magoarou , Stéphane Paquelet

We consider settings in which T multi-antenna transmitters and K single-antenna receivers concurrently utilize the available communication resources. Each transmitter sends useful information only to its intended receivers and can degrade…

Information Theory · Computer Science 2015-10-28 Rami Mochaourab , Eduard Jorswieck

The combination of energy harvesting and large-scale multiple antenna technologies provides a promising solution for improving the energy efficiency (EE) by exploiting renewable energy sources and reducing the transmission power per user…

Information Theory · Computer Science 2016-11-17 Zhenyu Zhou , Sheng Zhou , Jie Gong , Zhisheng Niu

We consider a single antenna narrowband multiple access channel in which users send training sequences to the base station and scheduling is performed based on minimum mean square error (MMSE) channel estimates. In such a system, there is…

Information Theory · Computer Science 2011-12-13 Jonathan Scarlett , Jamie Evans , Subhrakanti Dey

Superdirective (supergain) antennas aim to produce a narrow main beam from radiators that are electrically small compared with the wavelength. Instead of enlarging the physical aperture, they rely on strongly coupled currents, near-field…

Optics · Physics 2026-02-05 Alex Krasnok

As quantum communication systems and networks are becoming a commercial reality, clarity on their future infrastructure is increasingly important. Based on the inevitable presence of some amount of loss, chromatic dispersion, and timing…

Quantum Physics · Physics 2025-11-03 Marcus J. Clark , Siddarth K. Joshi

We address the problem of energy-error tradeoff in the discrimination between two linear passive quantum optical devices with a single use. We provide an analytical derivation of the optimal strategy for beamsplitters and an iterative…

Quantum Physics · Physics 2015-05-27 Alessandro Bisio , Michele Dall'Arno , Giacomo Mauro D'Ariano

Consider a control problem with a communication channel connecting the observer of a linear stochastic system to the controller. The goal of the controller is to minimize a quadratic cost function in the state variables and control signal,…

Information Theory · Computer Science 2018-11-27 Victoria Kostina , Babak Hassibi

Energy efficiency in fading channels in the presence of Quality of Service (QoS) constraints is studied. Effective capacity, which provides the maximum arrival rate that a wireless channel can sustain while satisfying statistical QoS…

Information Theory · Computer Science 2008-12-09 Mustafa Cenk Gursoy , Deli Qiao , Senem Velipasalar

This paper shows that wirelessly powered backscatter communications is subject to a fundamental tradeoff between the harvested energy at the tag and the reliability of the backscatter communication, measured in terms of SNR at the reader.…

Information Theory · Computer Science 2017-03-09 Bruno Clerckx , Zati Bayani Zawawi , Kaibin Huang