Maximum Gain, Effective Area, and Directivity

@article{Gustafsson2019MaximumGE,
  title={Maximum Gain, Effective Area, and Directivity},
  author={Mats G. Gustafsson and Miloslav Capek},
  journal={IEEE Transactions on Antennas and Propagation},
  year={2019},
  volume={67},
  pages={5282-5293}
}
  • M. Gustafsson, M. Capek
  • Published 11 December 2018
  • Engineering
  • IEEE Transactions on Antennas and Propagation
Fundamental bounds on antenna gain are found via convex optimization of the current density in a prescribed region. Various constraints are considered, including self-resonance and only partial control of the current distribution. Derived formulas are valid for arbitrarily shaped radiators of a given conductivity. All the optimization tasks are reduced to eigenvalue problems, which are solved efficiently. The second part of this paper deals with superdirectivity and its associated minimal costs… 
Upper bounds on absorption and scattering
A general framework for determining fundamental bounds in nanophotonics is introduced in this paper. The theory is based on convex optimization of dual problems constructed from operators generated
Optimal Bandwidth Positions for a Terminal Embedded Antenna: Physical Bounds and Antenna Design
This article considers a small embedded planar antenna in a square-shaped terminal of 25 cm2 at a frequency band near 900 MHz, intended for long-range communication. This article aims to shows how
A Method for Tailoring the Gain Pattern of a Single Antenna Element
In this paper, we present a novel method to tailor the radiation pattern of an antenna element, such as a single element of an array, by maximizing its partial radiation efficiency in the desired
GlobalToperator bounds on electromagnetic scattering: Upper bounds on far-field cross sections
We present a method based on the scattering $\mathbb{T}$ operator, and conservation of net real and reactive power, to provide physical bounds on any electromagnetic design objective that can be
Antenna Feed Array Synthesis for Efficient Communication Systems
Accurate synthesis of antenna radiation behavior is a complementary step towards simulation in antenna systems design process. In this paper, a spherical harmonic decomposition (SHD) and coupled
On the optical theorem and optimal extinction, scattering and absorption in lossy media
This paper reformulates and extends some recent analytical results concerning a new optical theorem and the associated physical bounds on absorption in lossy media. The analysis is valid for any
Simulation of Small Radio Telescope Antenna Parameters at Frequency of 1.42 GHz
The paper presents an overview of theoretical aspects of small radio telescope antenna parameters. The basic parameters include antenna beamwidth, antenna gain, aperture efficiency, and antenna
Fundamental Bounds for Multi-Port Antennas
TLDR
Current-density fundamental bounds are formulated for N-port radiators utilizing a port mode basis and significant reduction of size of underlying matrices allows for simultaneous optimization of ports’ placement and excitation amplitudes.
Harnessing superdirectivity in dielectric spherical multilayer antennas
Small form-factor, narrowband, and highly directive antennas are of critical importance in a variety of applications spanning wireless communications, remote sensing, Raman spectroscopy, and single
Improvement of Edge Brightening by Means of Q Factor Minimization in Circular Antenna Apertures: High Efficient Taylor-Like Patterns
TLDR
This procedure is devoted to search Taylor-like distributions which offer a good compromise between low and high efficiency values with potentials for the antenna design scenario, based on a decrease in edge brightening effects led by the minimization of the aforementioned <inline-formula> <tex-math notation="LaTeX">$Q$ </tex-Math></inline- formula> ratio.
...
...

References

SHOWING 1-10 OF 80 REFERENCES
Fundamental limitations in antennas
Four fundamental limitations in antennas have been identified in the areas of: electrically small antennas, superdirective antennas, superresolution antennas, and high-pin antennas. All exhibit
Degrees of Freedom and Maximum Directivity of Antennas: A bound on maximum directivity of nonsuperreactive antennas.
We derive a general fundamental directivity limitation formula that applies to nonsuperreactive antennas of any size that fit within a minimum sphere of any given radius rmin. The derivation is done
Optimal Currents on Arbitrarily Shaped Surfaces
An optimization problem has been formulated to find a resonant current extremizing various antenna parameters. The method is presented on, but not limited to, particular cases of gain G, quality
A new approach to the design of super-directive aerial arrays
The current distribution required for maximum directivity of an array with a finite number of elements and any specified geometrical configuration is shown to be completely defined by the self- and
Radiation Efficiency Cost of Resonance Tuning
TLDR
It is demonstrated that the assumption of lossless, lumped, and external tuning skews the true nature of radiation efficiency bounds when practical material characteristics are used in the tuning network.
Physical Bounds and Radiation Modes for MIMO Antennas
TLDR
A computationally efficient method for calculating the fundamental performance bound on spectral efficiency is presented, calculated for multiple-input-multiple-output (MIMO) antennas with a radiation efficiency requirement.
Radiation Efficiency Limits for Elementary Antenna Shapes
  • H. Thal
  • Engineering
    IEEE Transactions on Antennas and Propagation
  • 2018
Both the bandwidth and efficiency of antennas decrease as the physical size decreases. Bounds on the <inline-formula> <tex-math notation="LaTeX">${Q}$ </tex-math></inline-formula>-factor, inversely
Antenna excitation for maximum gain
The problem of obtaining the excitation of an antenna array for maximum power gain is considered in terms of network parameters defined at the input terminals. The reciprocal problem of loading an
Optimal Antenna Currents for Q, Superdirectivity, and Radiation Patterns Using Convex Optimization
TLDR
Convex optimization is used to determine current distributions that provide upper bounds on the antenna performance and formulations for maximal gain Q-Factor quotient, minimal Q-factor for superdirectivity, and minimum Q for given far-fields are presented.
Minimization of Antenna Quality Factor
TLDR
It is shown that the dual problem can easily be solved and always results in minimal quality factor, and the class of solvable problems is significantly extended.
...
...