Asem Al-Zoubi

A Broadband Center-Fed Circular Patch-Ring Antenna With a Monopole Like Radiation Pattern

A center-fed circular microstrip patch antenna with a coupled annular ring is presented. This antenna has a low profile configuration with a monopole like radiation pattern. Compared to the center-fed circular patch antenna (CPA), the proposed antenna has a large bandwidth and similar radiation pattern. The proposed antenna is fabricated and tested. It resonates at 5.8 GHz, the corresponding impedance bandwidth and gain are 12.8% and 5.7 dBi, respectively. Very good agreement between the measurement and simulation for the return loss and radiation patterns is achieved.

A Linear Rectangular Dielectric Resonator Antenna Array Fed by Dielectric Image Guide With Low Cross Polarization

Design of a linear array of rectangular dielectric resonator antennas (DRAs) fed by dielectric image guide (DIG) is presented. Coupling between the DIG and the DRAs is predicted using the effective dielectric constant method. In order to achieve a specific power distribution, the power coupled to each DRA is controlled by changing the spacing between the DRAs and the DIG. Cross polarization reduction is achieved by wrapping a conducting strip around the middle of the DRA without affecting the co-polarized radiation pattern. The antenna is fabricated and tested. Good agreement between the measured and computed results is obtained.

A Low-Profile Dual-Band Surface Wave Antenna With a Monopole-Like Pattern

A dual-band surface wave antenna (DBSWA) that realizes a monopole-like radiation pattern with a low-profile configuration is designed and measured. The antenna consists of two parts: a center-fed modified crosspatch to excite surface waves at two frequency bands, and a thin dielectric slab loaded with periodic patches to support the propagation of the surface waves. The surface wave property and radiation mechanism of the DBSWA are described, and parametric studies are performed to understand the dual-band characteristics of the antenna. The proposed antenna with only 3 mm thickness (< 0.05 lambda) is fabricated and tested, which resonates at 4.2 and 4.9 GHz. The corresponding impedance bandwidths and gains are 1.10% and 4.9 dBi for the low frequency band and 3.94% and 5.4 dBi for the high frequency band.

Analysis and Design of a Rectangular Dielectric Resonator Antenna Fed by Dielectric Image Line through Narrow Slots

Analysis and design of a narrow aperture coupled rectangular dielectric resonator antenna (DRA) fed by dielectric image line (DIL) are presented. The modal expansion method is used to describe the fields in the dielectric resonator side and the change in the modal voltage of the image line at the aperture is developed to analyze the single element DRA. The DIL is connected to the X- band rectangular waveguide through a waveguide transition and DIL tapering is used to match between the waveguide and the DIL.

Aperture Coupled Rectangular Dielectric Resonator Antenna Array Fed by Dielectric Image Guide

This paper presents the design of a rectangular dielectric resonator antenna array coupled to narrow slot apertures that are fed by dielectric image guide (DIG). The DIG is excited by an X-band rectangular waveguide through a waveguide transition, and DIG tapering is used to match between the waveguide and the DIG. Reflection cancelling slots are added near the original slots to improve impedance matching. Since the slots radiate in both directions, a reflecting conducting plate is inserted above the DIG to decrease the back radiation of the antenna. The antenna is fabricated and the measured results are compared to the simulated results.

Slot-aperture-coupled linear dielectric resonator array fed by dielectric image line backed by a reflector

The aperture coupled dielectric resonator antenna array fed by dielectric image line backed with a reflector was simulated using HFSS. A good return loss was obtained for an array of 7 DRA elements by adding cancelling slots with the radiating slots. Adding a reflector in the DIL side decreases the back radiation and increases the gain for the array.

Design of Linear Dielectric Resonator Array Fed by Dielectric Image Line Through Narrow Slots

Dielectric resonator antennas have been developed for the use in microwave and millimeter frequency bands; they have several advantages over the microstrip patch antennas such as smaller size, higher radiation efficiency, wider bandwidth, and no excitation of surface waves. Recently, the aperture coupled rectangular DRA fed by a microstrip line was analyzed. This paper presents an aperture coupled dielectric resonator antenna and arrays fed by dielectric image line (DIL). In exciting the DIL, the DIL is connected to the X-band rectangular waveguide three-section transition in order to reduce the return loss. HFSS commercial software was used to obtain the results for the transmission coefficient, return loss, and radiation patterns

A Dual Band Surface Wave Antenna with a Monopole Like Pattern

This paper presents a dual band surface wave antenna that radiates a monopole like pattern. The monopole like radiation pattern is realized by the diffractions of the surface waves, and the dual band operation is achieved using a modified cross strip feed with split branches. The return loss and the radiation patterns are presented to demonstrate the antenna characteristics

Analysis of Aperture Coupled Dielectric Resonator Antenna Fed by Dielectric Image Line

Dielectric resonator antennas (DRAs) have several advantages compared to microstrip patch antennas, such as smaller size, higher radiation efficiency, wider bandwidth, and no excitation of surface waves. This paper presents an aperture coupled dielectric resonator antenna fed by a dielectric image line. The modal expansion method is used to describe the field on the DRA side and the change in the modal voltage of the image line at the aperture is developed to analyze the single element DRA

Quasi-static analysis of asymmetric cylindrical coplanar waveguides with finite-extent ground

Quasi-static characteristics of asymmetric cylindrical coplanar waveguides (CCPWs) with finite-extent ground are analysed using the conformal mapping technique. Closed-form expressions for the effective permittivity and characteristic impedance of inside and outside asymmetric CCPWs with finite ground are derived. Using these expressions, the effect of various parameters on the characteristics of CCPWs is studied.