Results 141 to 150 of about 567,106 (189)

Impedance, bandwidth, and Q of antennas

IEEE Transactions on Antennas and Propagation, 2004
To address the need for fundamental universally valid definitions of exact bandwidth and quality factor (Q) of tuned antennas, as well as the need for efficient accurate approximate formulas for computing this bandwidth and Q, exact and approximate expressions are found for the bandwidth and Q of a general single-feed (one-port) lossy or lossless ...
A.D. Yaghjian, S.R. Best
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High-bandwidth force and impedance control for industrial robots

Robotica, 1998
Common geared industrial robots call for force control methods with special properties such as good rejection of frictional disturbances, smoothness of corrective motions, and more. A new method is presented which meets these requirements and provides a high control bandwidth. In the manner of hybrid control, directions of a task frame can be selected
Eckhard Freund, Jürgen Pesara
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Strategies for finding a bandwidth-optimal topology for impedance matching

2013 European Conference on Circuit Theory and Design (ECCTD), 2013
When searching for an impedance matching circuit yielding the maximum bandwidth with certain number of matching elements, the choice of the correct topology is crucial. Compared to optimal two-element (L-section) matching, the improvement of bandwidth provided by a third element can be anything from negligible to significant.
Anu Lehtovuori, Risto Valkonen
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Extended-Bandwidth Negative Impedance Converters by Nested Networks

IEEE Transactions on Circuits and Systems II: Express Briefs, 2018
We show a novel scheme for increasing resistive bandwidth in opamp negative impedance converters (NICs) with recursive topologies. A simplified theoretical model indicates bandwidth improvement due to altering pole and zero locations in the network’s transfer function by allowing certain resistor terms to take negative values.
Aubrey N. Beal, Jonathan N. Blakely, Ned J. Corron   +2 more
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Bandwidth limitations of dipoles matched with non-foster impedances

2nd European Conference on Antennas and Propagation (EuCAP 2007), 2007
In this paper, the bandwidth limitations of dipoles matched with negative impedance components are discussed. In theory, infinite impedance bands are possible with non-Foster impedances, but in practice the fields stored inside the smallest sphere enclosing the antenna limit the band.
Hujanen, Arto, Holmberg, Jan, Sten, Johan, Hirvonen, Mervi   +4 more
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Antenna bandwidth broadening with a negative impedance converter

International Journal of Microwave and Wireless Technologies, 2013
Cognitive radio (CR) has generated a lot of interest because of the promise of wide instantaneous bandwidths which will improve data rates. Current social trends suggest that CR nodes will ultimately be mobile and handheld. This produces a need for small wideband antennas. The Chu limit imposes a restriction on what is obtainable with passive matching.
Oluwabunmi O. Tade, Peter Gardner, Peter S. Hall   +2 more
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Impedance Bandwidth Enhancement For UWB Slot Antenna

2007 International workshop on Antenna Technology: Small and Smart Antennas Metamaterials and Applications, 2007
A design for enhancing impedance bandwidth of wideband slot antenna is proposed and studied. The wideband slot antenna with a finite ground plane on the 50 ohm SMA connector is used for enhancing the impedance bandwidth. The measured results of the proposed antenna show that the impedance bandwidth is related with dimensions of a finite ground plane ...
Dau-Chyrh Chang, Ji-Chyun Liu, Bing-Hao Zeng, Ming-Yen Liu   +3 more
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A planar antenna with very wide impedance bandwidth

2008 International Conference on Microwave and Millimeter Wave Technology, 2008
A novel simple structure and wideband planar antenna is proposed. The antenna is in form of a rectangular copper patch with one vertical slot and two transverse slots. The proposed antenna can be matched to the intrinsic impedance of an ordinary coaxial cable (50 Omega) without using parasitic elements or balun circuits.
null Zhang Guangqiu, null Tu Zhen, null Xing Feng, null Wang Zhichen   +3 more
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Theoretical Methods for the Impedance and Bandwidth of the Thin Dipole

IEEE Antennas and Propagation Magazine, 2013
The dipole is the fundamental elemental antenna, and the wire electric dipole and its monopole equivalent are still widely used in practice. Despite the long history of dipole research, its complete impedance behavior remains elusive, because of long-standing shortfalls in modeling the feed.
Maryam Dehghani Estarki, Rodney G. Vaughan   +1 more
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On bounds of the impedance matching bandwidth for antennas

2015 International Conference on Electromagnetics in Advanced Applications (ICEAA), 2015
Bounds on optimal bandwidth for antennas are important in antenna design, since it sets the stage for what is achievable in the design. Recently several different bandwidth bounds have been obtained. In the present paper we compare two different bandwidth bound approaches, and apply it to antenna data.
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