The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Design and analysis of a linearly polarized Ka-Band single layer Reflectarray (RA) based on the principle of dielectric perforation, are presented. The phase characteristics of a single layer unit cell is obtained by varying single air via diameter, located at the cell center. A 340 degrees reflected phase is realized. The resulted 29*29 air vias array design shows good performance in lowering Side...
A circularly polarized dielectric resonator antenna (CPDRA) configuration is proposed, analyzed, investigated, and optimized using the CST-MW-simulator. The presented antenna is fed by a microstrip sequential phase power divider (MSPPD). Both microstrip and DRA have numerous benefits in wireless communication and radar systems applications. This is due to their small size, low cost, less weight, easy...
A simple SIW H-plane horn antenna with a loaded open cavity is introduced. The new combination of the SIW H-plane horn and the open cavity results in a wide and constant impedance bandwidth, which has been hard to achieve by a single SIW horn antenna. Besides matching improvement, the new configuration results in higher gain with radiation pattern focused in antenna aperture. The longitudinal size...
A new compact DRA is designed from very high dielectric constant, but with wideband characteristics. The DR is residing on a dielectric substrate with wide opining in the ground plane. Printed microstrip line is exciting the DR. This element achieves 60% bandwidth. However, it has bidirectional radiation patterns. A reflector is used to ho have a unidirectional radiation. To keep the wideband characteristics,...
An accurate and fast analytical formulation for the radiation fields of a slot antenna covered with a superstrate is proposed. The analytical formulation is based on the transmission line analogy in conjunction with the reciprocity theorem. The slot antenna working at 60 GHz is formed in the top plate of a microstrip ridge gap waveguide (RGW) structure. The proposed analytical formulation is validated...
A 2 × 2 planar slot antenna array is designed at 60 GHz. The slots are excited by a printed corporative feeding network based on the ridge gap waveguide (RGW) technology. Such a network, requires more than a full wavelength spacing between the slots, which cause excitation of undesired grating lobes. In order to reduce the grating lobes level, multilayer dielectric superstrates are placed above the...
A simple and efficient transition from microstrip to printed ridge gap waveguide for millimeter-wave band is proposed. The transition covers the complete available bandwidth provided by ridge gap waveguide. The transition is used for feeding and measurement of a bandpass filter. Measured results are in good agreement with the simulation.
The Textile materials are widely used recently in microwave applications. The wearable antennas and the medical applications generate high potential to explore the electrical characteristics of the Textile materials. The mechanical properties of such materials are well known but the challenge is to determine the electric characteristics in an accurate way specially the relative permittivity. There...
Recently, Ridge Gap Waveguides (RGW) become one of the most promising waveguide technologies. This type of guiding structures carries the signal in the form of Quasi TEM wave inside an air gap. This leads to less dispersion in the propagating signal and uniform field distribution across the guide. Here, a design of a magic tee feeding a splitted ridge gap line is presented. This ridge gap splitted...
An optically transparent reflectarray antenna unit cell design is proposed for integration with solar cells using staked perforated sheets of Acrylic. The design accommodates accurately the effect of solar cells on adjacent electromagnetic waves. The choice of the best possible transparent material for the design is presented based on the availability and ease of machining to the desired structure...
An investigation is performed to find the optimum radiation patterns for a reflectarray feed for maximum aperture efficiency. The radiation pattern is synthesized to uniformly illuminate a reflectarray aperture within a specified subtended angle through an inverse problem. Theoretical efficiency analysis for the proposed radiation pattern and its realizable approximation is invoked in comparison to...
A new printed planar technology is introduced for efficient TEM bandpass filters in millimeter band. The new technology is self-packaged and shows excellent insertion losses compared to microstrip filters. The designs are based on newly introduced ridge gap waveguide, which is composed of printed parallel plate waveguide surrounded by arrays of bed of mushrooms. Several example are designed and optimized...
Phase correction due to finite reflectarray (RA) antenna size and edge diffraction (ED) is proposed. The process is based on the numerical full wave analysis. The edge diffraction is mainly caused because of amplitude and phase ripples at sharp knife-edges of the outer perimeter of the RA antenna. The diffracted fields at the edges is diffracted in all directions resulting in disturbing the original...
A simple and low-cost solution to reduce the coupling between two slot antennas working at 60 GHz is presented. The slot antennas formed in the top plate of printed ridge gap waveguide (PRGW) structure to avoid the losses associated with conventional feeding mechanisms. The coupling reduction of more than 10 dB is achieved by removing a part of the top metallic plate of the PRGW between the two slots...
A new configuration has been used for design of a wideband resonator-coupled bandpass filter with high rejection on both sides of the passband. Corrected group delay in combination with space mapping was used to calculate the initial dimensions, which provides a response that is sufficiently close to ideal response in order to be used in full-wave optimization. The design was fabricated and measurements...
A novel broadband flip-flop low profile Reflectarray (RA) is designed for Ka-Band based on the principle of dual side printed substrate. First, the reflected wave phase curve is obtained by varying the patch size on top layer while energy is coupled through a bottom slot of equal size to the patch. Such a cell provides 360° degress reflected phase with almost linear behavior. Second, the element is...
A dual layer, dual reflector leaky wave antenna for broadside radiation is presented. The antenna has compact size since one layer is dedicated for reflector feeds and the other layer for leaky slot array. The tapered leaky slots are fed by out-of-phase waves coming from reflectors travelling in opposite directions so that the broadside radiation patterns are achieved with over 20% frequency band...
A simple, fast, and efficient approach to solve the electromagnetic (EM) scattering problem from arbitrary object is offered by the Random Auxiliary Sources (RAS) method. Based on direct application of the boundary conditions and projection of radiating modes with infinitesimal sources, the method is able to accurately solve problems with much less execution time than other comparable methods. The...
A simple, fast, and efficient numerical solution for the electromagnetic scattering from 2-D arbitrary objects is proposed.
Based on the surface equivalence principle and the use of novel equivalent problems with random auxiliary
sources, more degrees of freedom are added, resulting in significantly fast solutions. Furthermore, the simplicity of
the implementation is ensured by placing equivalent...
A contactless Wheeler cap setup is proposed to measure the radiation efficiency of arbitrary moderate size antennas. A magnetic conductor flange surrounds the conventional Wheeler cap opening to be parallel to a conducting/nonconducting ground plane. Such arrangement suppress the leakage from the cavity without a need for electrical contact. The magnetic conductor is realized by an Electromagnetic...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.