Prof. Richard Ziolkowski: Electrically Small Antennas – Advances in Efficiency, Bandwidth, and Directivity

Prof. Richard Ziolkowski, University of Arizona, will provide a seminar on electrically small antennas. This seminar is part of the University of Calgary Department of Electrical and Software Engineering Research Seminar Series.

After the 1-hour presentation, there will be an opportunity to meet with Dr. Ziolkowski. Light refreshments and pizza will be provided.

The introduction of metamaterials and metamaterial-inspired structures into the tool set of RF engineers has led to a wide variety of advances within research and application areas treating structures that radiate (e.g., RF antennas) and scatter (e.g., optical nano-antennas). The increased awareness of complex media, both naturally occurring and artificially constructed, which has been stimulated by the debut of metamaterials, has enabled paradigm shifts in terms of our understanding of how devices and systems operate and our expectations of their performance characteristics. These shifts include the trends of miniaturization, enhanced performance (total radiated power, bandwidth and directivity), reconfigurability and multifunctionality. New techniques have been developed that are truly beginning to impact practical realizations and their applications.

A variety of metamaterial-inspired, near-field resonant parasitic (NFRP), electrically small antennas have been developed that exhibit multifunctional performance, enhanced bandwidths, and higher directivities. Their engineering is achieved by combining multiple NFRP elements with simple driven radiators. Higher directivity is obtained by simultaneously exciting balanced electric and magnetic NFRP elements, leading, for example, to endfire and broadside radiating Huygens dipole antennas (HDAs). Enhanced bandwidths and loss mitigation, as well as wireless power transfer capabilities, have been achieved by augmenting the HDAs with non-Foster (active) and rectifying (rectenna) elements. A variety of HDAs and arrays of them have been fabricated and tested to confirm their attractive performance characteristics; they will be reviewed briefly.

Nonetheless, even more highly directive antenna systems are being sought to address the perceived needs of the NextG / XG wireless systems and their applications. Combinations of higher order multipole electric and magnetic radiating elements have been developed that achieve unidirectional performance with even higher directivities. Several of these unidirectional mixed-multipole antennas (UMMAs) have been fabricated and tested to confirm their attractive properties. They too will be reviewed briefly.

Speaker(s): Prof. Richard Ziolkowski, University of Arizona,

Room: 516, Bldg: ICT, 856 Campus Pl NW, Calgary, Alberta, Canada