Electrically Small Superconducting Antennas With Bandpass Filters

• Published in: IEEE transactions on applied superconductivity Vol. 17; no. 2; pp. 878 - 881
• Main Authors: Oda, S., Sakaguchi, S., Kanaya, H., Pokharel, R.K., Yoshida, K.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: New York, NY IEEE 01-06-2007; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Antenna theory; ANTENNAS; Applied sciences; Band pass filters; Bandpass filter; Capacitors. Resistors. Filters; Circuit design; Circuit properties; Circuit simulation; COMPUTER SIMULATION; Coplanar waveguide; COPPER OXIDE; Dipole antennas; Distributed parameter circuits; ELECTRIC CIRCUITS; Electric, optical and optoelectronic circuits; Electrical engineering. Electrical power engineering; Electrical power engineering; Electronic circuits; Electronic equipment and fabrication. Passive components, printed wiring boards, connectics; Electronics; Exact sciences and technology; Frequency filters; High temperature superconductors; MAGNESIUM OXIDE; MAGNETIC FIELD; Matching; miniaturized impedance matching circuit; Miscellaneous; Power networks and lines; Slot antennas; slot loop antenna; Superconducting filters; Superconducting transmission lines; SUPERCONDUCTORS; Transmission line theory; Transmission lines; Various equipment and components; YTTRIUM OXIDE; Performance evaluation; slot loop antenna; Circuit design; Return loss; Matching circuit; Experimental study; Dipole antenna; Bandpass filter; Transmission line; Impedance matching; Electrical network; Slot antenna; Coplanar waveguide; Band pass filter; System simulation; Electromagnetic field; Coplanar waveguides; Miniaturization; Permittivity; TLM method; Simulator; High temperature superconductor; miniaturized impedance matching circuit; Loop antenna
• ISSN: 1051-8223; 1558-2515
• DOI: 10.1109/TASC.2007.898273

In order to reduce the size of a wireless system, we have proposed the design formulas for an electrically small antenna (ESA), i.e. an antenna whose dimension is much smaller than a wavelength, with a miniaturized matching circuit which connects to a 50 Omega external circuit. Theoretical performances of the slot dipole antenna with the impedance matching circuit designed by the present theory are studied by the electrical circuits using transmission lines (transmission line model) as well as the electromagnetic (EM) field simulator. We designed a slot dipole antenna with the aid of the simulations using the electrical circuits as well as the EM field simulator. The size of the designed antenna including the matching circuit is 4.1 mm times 1.9 mm on MgO substrate with relative permittivity of 9.6 at the center frequency of 5 GHz, and the designed fractional bandwidth is 13% @RL (return loss) = -3 dB. In order to demonstrate the theory, we also carried out experiments on the slot dipole antenna with the matching circuits of pole number n = 2 using high temperature superconductors YBCO on MgO substrates in the 5 GHz band.