P. Abdulla

Dielectric ring resonator band pass filter for 2.4 GHz WLAN frequencies

A Microwave band pass filter employing dielectric ceramic ring resonator is designed, fabricated and tested. Band pass filter characteristics are studied by measuring the return loss and transmission characteristics of the microstrip line fed dielectric ring resonator. S-parameters, electric field and magnetic field distributions are computed using FEM method and compared with measured results. The measured values agree with predicted values obtained using FEM. Centered at 2404 MHz the fabricated dielectric ring resonator filter shows a measured 3-dB band width of 20.6 MHz.

Waveguide-fed cylindrical DRA: Wide-band design

A cylindrical dielectric resonator antenna (DRA) is excited by a thick ground plane slot, which is fed by a capacitive waveguide junction (CWJ) coupled waveguide end. The objective of using a CWJ is to substantially increase the power coupling to the DRA. The DRA when given an offset along its length and width relative to the slot leads to wide band operation of the DRA. Measurements were carried out to verify the simulations and a reasonable agreement between them is obtained.

Theoretical and experimental study on broad wall slot coupled dielectric resonator antennas

Broad wall longitudinal slot coupled Hemispherical DRA (HDRA) being analyzed using method of moments (MoM). The slot electric field is described using entire domain sinusoidal basis function and the continuity of magnetic tangential field at the slot aperture is enforced to determine the actual electric field. Thickness of the slot is analyzed using cavity Greens functions. The computed data is compared with the measurement and commercially available code.

Miniaturized bandpass filter using a dual-mode octagonal patch resonator

This paper presents design of a bandpass filter using a novel dual-mode miniaturized octagonal patch resonator. Two slots in orthogonal position are cut on the patch to reduce the resonance frequency. Two circular holes connected by a slot are used to perturb the two degenerate modes of the patch. The proposed filter is 64% smaller compared to an octagonal patch without any slots.