By Topic

On the inverse relationship between quality factor and bandwidth of small antennas

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$33 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

2 Author(s)
Amir Khurrum Rashid ; School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 ; Zhongxiang Shen

Relationship between the reflection coefficient bandwidth and quality factor (Q) of a small antenna is revisited using a simple frequency independent model. A tuned small antenna is considered in this case, which is modeled as either a series or a shunt RLC network. When the antenna resistance is matched with the characteristic impedance of the feed-line, both configurations lead to an identical relation, which is also interestingly identical to the well-known inverse bandwidth-Q formula for small antennas. However, this well-known formula is only applicable when the antenna is perfectly matched to its feed line. In this paper, a more general and yet simple form of this expression is derived, which can encompass the effect of mismatch between the antenna and its feed-line. Furthermore, we derive separate relations for the bandwidth-Q product, for both the loaded and unloaded cases. As an illustrative example, a microstrip patch antenna is considered to validate the results.

Published in:

2009 Asia Pacific Microwave Conference

Date of Conference:

7-10 Dec. 2009