Journal ArticleDOI
Physical limitations of antenna
TLDR
In this paper, a discussion of minimum possible antenna quality factor (Q) is presented based on the spherical wave function theory and the maximum possible ratios of gain to Q for both directional antenna and omnidirectional antenna are examined and new upper limits for both cases have been obtained.Abstract:
A discussion of minimum possible antenna quality factor (Q) is first presented . Based on the spherical wave function theory, the maximum possible ratios of gain to Q for both directional antenna and omnidirectional antenna are examined and new upper limits for both cases have been obtained. Universally applicable numerical results and some related discussions are also included.read more
Citations
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Journal ArticleDOI
A Review of Passive RFID Tag Antenna-Based Sensors and Systems for Structural Health Monitoring Applications
TL;DR: The challenges and state-of-the-art methods of passive RFID antenna sensors and systems in terms of sensing and communication from system point of view are highlighted and future trends are discussed.
Journal ArticleDOI
Experimental Validation of Performance Limits and Design Guidelines for Small Antennas
Daniel F. Sievenpiper,David Carlos Dawson,Minu M. Jacob,Tumay Kanar,Sanghoon Kim,Jiang Long,Ryan Quarfoth +6 more
TL;DR: In this article, the theoretical performance limit for small antenna performance has been validated by all available experimental evidence and the theoretical predictions for the performance due to design factors such as permittivity, aspect ratio, and the internal structure of the antenna are also supported by the experimental evidence.
Journal ArticleDOI
A Novel Metal-Mountable Electrically Small Antenna for RFID Tag Applications With Practical Guidelines for the Antenna Design
Jun Zhang,Yunliang Long +1 more
TL;DR: Study demonstrate that the proposed antenna is a good candidate for ultra-high-frequency RFID tags to be mounted on metallic surfaces, especially in size-constrained scenarios, and a figure of merit, namely, NBG, is presented, with which a comparison among electrically small tag antennas is carried out.
Journal ArticleDOI
Optimal Currents on Arbitrarily Shaped Surfaces
Lukas Jelinek,Miloslav Capek +1 more
TL;DR: In this paper, the Rao-Wilton-Glisson basis representation is used to simplify the underlying algebra while still allowing surface current regions of arbitrary shape to be treated, and it is shown that the optimal current can, in principle, be found as a combination of a few eigenmodes.
References
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Book
Time-harmonic electromagnetic fields
TL;DR: In this paper, a revised version of the Revised edition of the book has been published, with a new introduction to the concept of plane wave functions and spherical wave functions, as well as a detailed discussion of the properties of these functions.
Journal ArticleDOI
Physical Limitations of Omni-Directional Antennas
TL;DR: In this paper, the physical limitations of omni-directional antennas are considered and the potentiality of a broad band width of an antenna with the maximum dimension of 2a has been shown.
Journal ArticleDOI
Effect of antenna size on gain, bandwidth, and efficiency
TL;DR: It is found that the maximum gain obtainable from a broad-band antenna is approxima tely equal t o that of the uniformly Illuminated aperture, and if higher gain is desired, the antenna mus t necessarily be a narrow-band device.
Journal ArticleDOI
Fundamental limitations in antennas
TL;DR: In this article, four fundamental limitations in antennas have been identified in the areas of: electrically small antennas, super-directive antenna, superresolution antennas, and high-pin antennas.
Journal ArticleDOI
Evaluation of antenna Q
R. Collin,S. Rothschild +1 more
TL;DR: In this paper, a method is presented for evaluating the Q of an antenna, where the Q is defined as in conventional network theory, and the method consists of subtracting the energy density associated with the power flow from the total energy density, thus enabling the magnetic and electric reactive energy to be computed.