An Ultrawideband Conformal Capsule Antenna With Stable Impedance Matching
Keywords
Conformal capsule antenna; inner wall; slot antenna; wideband
Abstract
An ultrawideband conformal capsule slot antenna, which has a simple configuration and a stable impedance matching characteristic, is described in this paper. In the past, wideband outer-wall antennas have been proposed for capsule-type applications. However, this paper shows that the outer wall is not a good choice for placing capsule antennas, since such a choice exhibits a high specific absorption ratio, low gain, and low efficiency. Instead, the antenna proposed in this paper is conformal to the inner wall of a capsule shell, and it provides a wide impedance bandwidth ranging from 1.64 to 5.95 GHz (113.6%). Furthermore, the impedance matching remains stable even with a change in the operating environment. Since in a typical application scenario a capsule will move through the digestive system, and thus experience varying environments, a wide bandwidth and stable performance are both very desirable attributes of the antenna, whose design is discussed in this paper. Moreover, the proposed antenna continues to maintain a stable impedance match even when a battery is added inside the capsule, or when there is a change in the battery size and/or its position. Given these advantages, we argue that slot antennas are well suited for incorporation into capsule antennas for the present application.
Publication Date
10-1-2017
Publication Title
IEEE Transactions on Antennas and Propagation
Volume
65
Issue
10
Number of Pages
5086-5094
Document Type
Article
Personal Identifier
scopus
DOI Link
https://doi.org/10.1109/TAP.2017.2741027
Copyright Status
Unknown
Socpus ID
85028512053 (Scopus)
Source API URL
https://api.elsevier.com/content/abstract/scopus_id/85028512053
STARS Citation
Bao, Zengdi; Guo, Yong Xin; and Mittra, Raj, "An Ultrawideband Conformal Capsule Antenna With Stable Impedance Matching" (2017). Scopus Export 2015-2019. 5957.
https://stars.library.ucf.edu/scopus2015/5957