Designing of Enhanced Gain Aperture Coupled Dielectric Resonator Antenna

Abstract

Recent advances in the wireless communications have resulted in the development of antennas, which can be embedded into wireless products. For the last three decades, two classes of antennas i.e., the microstrip patch antenna (MPA) and the dielectric resonator antenna (DRA) have been under investigation for the modern wireless communication applications. MPA consists of a radiating patch on one side of the dielectric substrate with a ground plane on other side. MPAs are attractive due to their light-weight, low-profile planar configuration, conformability and low-cost as compared to the conventional antennas. These are highly compatible with embedded antennas in the handheld wireless devices, such as cellular phones and pagers etc. Another area, where the patch antennas have been used successfully, is satellite communication. MPAs radiate primarily because of the fringing fields between the patch edge and ground plane. For appropriate antenna performance, a thick dielectric substrate having a low dielectric constant is used to provide better efficiency, larger bandwidth (BW), and better radiation. But, such a configuration leads to a large antenna size. However, in order to design a compact MPA, higher dielectric constants are used, which are less efficient and result in narrower bandwidth. Moreover, MPAs have various limitations like narrow bandwidth, more metal losses (ohmic losses), low-gain, surface-wave excitation and poor polarization purity etc. Most of the limitations of patch antenna are removed in DRAs. Dielectric resonator antenna consists of the dielectric materials in its radiating patch (also called as dielectric resonators) on one side of the substrate and has a ground plane (metal) on the other side. These DRA configurations have received great interest in the recent years for its potential applications in the microwave and millimeter-wave communication systems. These have been widely used as a tuning component in the shielded microwave circuits, such as filters, oscillators and cavity resonators.