Uniformly Improved Cross-polar Discrimination in a Dielectric Resonator Antenna by Conduction Current Control

• Published in: IEEE transactions on antennas and propagation Vol. 71; no. 3; p. 1
• Main Authors: Rafidul, Sk, Mishra, Puneet Kumar, Bose, Rajat, Guha, Debatosh
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.03.2023; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: C band; Conduction current control; cross-polarized radiation; Current distribution; diagonal plane; dielectric resonator antenna (DRA); Dielectric resonator antennas; Dielectrics; Geometry; Ground plane; Magnetic resonance; Metals; Radiation; Radio antennas; Resonators; Strips; Substrates
• ISSN: 0018-926X; 1558-2221
• DOI: 10.1109/TAP.2023.3240074

This work, for the first time, investigates the comprehensive sources of cross-polarized (XP) radiation from a dielectric resonator antenna (DRA). The study uses a recently developed theory on DRA radiation and models the XP sources with the help of well-known definition by Ludwig. This eventually focuses on the conduction current distribution on the metallic ground. The interpretation leads to a concept of synthesizing effective conduction current in order to satisfying the required condition of low XP fields. A representative prototype of a cylindrical DRA on engineered ground plane has been realized to operate in C-band. It exhibits nearly 12 % matching bandwidth with more than 25 dB co-to-cross polar discrimination over both orthogonal (H-) and diagonal (D-) planes. Relative improvement in XP level promised by the measured data is ~15 dB in D- and ~10 dB in H-planes. This proof of concept may now be extended to other DRA geometries and for practical applications in the near future.