Conference Paper

Design of miniaturized slot antennas

Dept. of Electr. Eng. & Comput. Sci., Michigan Univ., Ann Arbor, MI
DOI: 10.1109/APS.2001.959526 Conference: Antennas and Propagation Society International Symposium, 2001. IEEE, Volume: 4
Source: IEEE Xplore

ABSTRACT A procedure for the design of a novel small slot antenna is
presented. Using this method enables us to achieve a perfectly matched
antenna with a fairly high efficiency for a given arbitrary small size.
The miniaturization is achieved by terminating the short slot by an
inductor. Inductive loading is realized by coiling the shortened slot
line with a length of less than a quarter wavelength. Although the
choice of antenna size is optional, it is subject to limitations such as
antenna bandwidth and gain/efficiency. However, the directivity of this
small dipole-slot antenna, in the limit, is equal to that of the
infinitesimal Hertzian dipole, and its gain depends on the substrate
material specifications and antenna size. Microstrip line is used to
feed the antenna, which provides more stable feeding compared to coaxial
feed. Then simulation results for a prototype antenna at 300 MHz as well
as the input impedance and radiation pattern of the antenna are
presented and compared with measurements

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