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State-space models for stored energy and Q-factors

Gustafsson, Mats LU (2016) 2016 URSI International Symposium on Electromagnetic Theory, EMTS 2016 In 2016 URSI International Symposium on Electromagnetic Theory, EMTS 2016 p.226-228
Abstract

Q-factors are often used to quantify bandwidth performance of resonant structures. The Q-factor is defined as the quotient between the stored and dissipated energies. The time average dissipated energy is reformulated in the dissipated power and is well defined. The definition and evaluation of the stored energy is much more challenging and there are presently several proposals but none is applicable for general radiating system. The main challenge is to separate the radiated and stored parts of the total energy. In this paper, an alternative approach is proposed that is based on a state-space model of the antenna. The state-space model describes the internal states of the system and models the states that stores the energy. The... (More)

Q-factors are often used to quantify bandwidth performance of resonant structures. The Q-factor is defined as the quotient between the stored and dissipated energies. The time average dissipated energy is reformulated in the dissipated power and is well defined. The definition and evaluation of the stored energy is much more challenging and there are presently several proposals but none is applicable for general radiating system. The main challenge is to separate the radiated and stored parts of the total energy. In this paper, an alternative approach is proposed that is based on a state-space model of the antenna. The state-space model describes the internal states of the system and models the states that stores the energy. The state-space model is determined from the impedance matrix of the electric field integral equation. This provides a computationally efficient way to determine the stored energy that can be used in antenna current optimization. The state-space approach offers also new insight into the challenges to define the stored energy for electrically large objects.

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Please use this url to cite or link to this publication:
author
organization
publishing date
type
Chapter in Book/Report/Conference proceeding
publication status
published
subject
in
2016 URSI International Symposium on Electromagnetic Theory, EMTS 2016
pages
3 pages
publisher
Institute of Electrical and Electronics Engineers Inc.
conference name
2016 URSI International Symposium on Electromagnetic Theory, EMTS 2016
external identifiers
  • scopus:84992125315
ISBN
9781509025022
DOI
10.1109/URSI-EMTS.2016.7571359
language
English
LU publication?
yes
id
bafa1b8c-9d2a-4048-a8d3-e74b28356d8b
date added to LUP
2016-11-16 14:48:52
date last changed
2017-01-01 08:39:50
@inproceedings{bafa1b8c-9d2a-4048-a8d3-e74b28356d8b,
  abstract     = {<p>Q-factors are often used to quantify bandwidth performance of resonant structures. The Q-factor is defined as the quotient between the stored and dissipated energies. The time average dissipated energy is reformulated in the dissipated power and is well defined. The definition and evaluation of the stored energy is much more challenging and there are presently several proposals but none is applicable for general radiating system. The main challenge is to separate the radiated and stored parts of the total energy. In this paper, an alternative approach is proposed that is based on a state-space model of the antenna. The state-space model describes the internal states of the system and models the states that stores the energy. The state-space model is determined from the impedance matrix of the electric field integral equation. This provides a computationally efficient way to determine the stored energy that can be used in antenna current optimization. The state-space approach offers also new insight into the challenges to define the stored energy for electrically large objects.</p>},
  author       = {Gustafsson, Mats},
  booktitle    = {2016 URSI International Symposium on Electromagnetic Theory, EMTS 2016},
  isbn         = {9781509025022},
  language     = {eng},
  month        = {09},
  pages        = {226--228},
  publisher    = {Institute of Electrical and Electronics Engineers Inc.},
  title        = {State-space models for stored energy and Q-factors},
  url          = {http://dx.doi.org/10.1109/URSI-EMTS.2016.7571359},
  year         = {2016},
}