A band-notched filtering omnidirectional dielectric resonator antenna with metal patches

Abstract

In this paper, a laminated planar feed structure has been proposed to excite the omnidirectional radiation modes of a dielectric resonator (DR): TM01δ, TM011+δ and TM012+δ. The resonant frequencies of the three modes are 2.44, 2.78 and 3.10 GHz respectively. By combining three resonant frequencies, the proposed band-notched dielectric resonator antenna (DRA) achieves a wide impedance bandwidth and stable omnidirectional radiation pattern in the whole passband. The simulated passbands of the proposed band-notched DRA are 2.23–2.56 GHz and 2.71–3.17 GHz. The laminated planar feed structure also can produce an adjustable radiation null (RN) at the upper edge of the passband, improving the skirt selectivity. To suppress in-band interference, four metal patches have been plated on the side walls of the DR and another adjustable RN (notched frequency) is generated within the passband. By changing the size of the metal patch, the notched band can be adjusted. In a word, the proposed DRA has numerous advantages such as wideband, stable omnidirectional radiation, filtering and band-notched functions. A prototype has been fabricated and measured for demonstration, and the measured results are coincided with the simulated ones.