Frequency Reconfigurable Filtering Dielectric Resonator Antenna with Harmonics Suppression

Research output: Journal Publications and ReviewsRGC 21 - Publication in refereed journalpeer-review

45 Scopus Citations
View graph of relations



Original languageEnglish
Pages (from-to)3224-3233
Journal / PublicationIEEE Transactions on Antennas and Propagation
Issue number6
Online published29 Dec 2020
Publication statusPublished - Jun 2021


A filtering dielectric resonator (DR) antenna (DRA) that does not require any filtering circuits is investigated. It deploys a rectangular DR and three slots fabricated in the ground plane. The antenna is excited in the fundamental TEy1δ1 DRA mode and two slot modes. By making use of these three modes, two tunable radiation nulls near the edges of the passband can be obtained, giving filtering effects without the need of any filtering circuits. In this paper, the design, with minor modifications of the slots, is extended to a frequency-reconfigurable filtering DRA by using varactors. Its stopband can be extended to the third harmonic. By varying the voltages of the varactors, the antenna has a continuous frequency agility of 27.7% (2.15–2.84 GHz), with almost the same harmonics suppression level. The antenna has a gain of ~5.0 dBi and a rejection level of over 16.1 dB across the stopband. Its total antenna efficiency in the passband is ~81%, whereas it is generally lower than the average value of 1.8% in the stopband (up to 7.0 GHz). Comparing with the reported frequency-reconfigurable filtering antennas, our design has a better frequency agility, more stable filtering response, and weaker radiation in the stopband.

Research Area(s)

  • Antenna measurements, Antennas, defected ground structure (DGS), dielectric resonator antenna (DRA), Filtering, Filtering antenna, frequency reconfigurable antenna, harmonics suppression, Passband, Resonant frequency, Substrates