A new shaped circularly polarized dielectric resonator antenna (CP DRA) is studied with branch-line coupler and log-periodic balun for the GPS application. Since the coupler and balun are located under the DRA, it does not increase the footprint of the antenna, as a result the system is very compact. Two configurations are considered in this paper. In the first configuration, an external 50Ω lo...

lenses are often used to converge electromagnetic wave namely they convert incident phase front of feed antenna to a flat phase front. together, the lens and the feed create an electrically large aperture antenna. flat lenses provide the cost and weight benefits of the reflect-arrays, while maintaining the advantages of a lens antenna. these lenses use an array of unit-cells which are excited b...

Circularly-polarized antenna is built based on a new SIW (substrate integrated waveguide)structure which contains cavity-backed resonator and a conventional polarized ring with twosquare slits in inner and outer ring that differ 90° at position and is proposed for right-handedcircular polarization (RHCP) and fabricated in two separate layers. A broadband impedancebandwidth of 13.9% and a RHCP a...

The combination of Multiple-Input Multiple-Output (MIMO) and Orthogonal Frequency Division Multiplexing (OFDM) technologies gives wireless communications systems the advantages of lower bit error rate (BER) and higher data rate in frequency-selective fading environments. However, the main drawbacks of MIMO systems are their high complexity and high cost. Therefore, antenna selection in MIMO sys...

This paper presents a novel electrical polarization tracking method for mobile satellite communication systems that use linear polarization. It consists of two main technologies; the first estimates the mobile station antenna’s relative polarization angle against that of the satellite’s onboard antenna, the second forms counter polarization against the estimated value. We use a Ku-band communic...

An axially corrugated horn antenna with an elliptically shaped taper is proposed for satellite communication applications. This structure is a good candidate for the feed of reflectors and also for improving the electrical properties of reflector antennas. A tapering method is used to justify the horizontal location of the corrugation profile which improves the electrical performance of the pre...

circularly-polarized antenna is built based on new SIW(substrate integrated waveguide)structure which contains cavity-backed resonator and a conventional polarized ring with twosquare slits in inner and outer ring that differ 90° at position and is proposed for right-handedcircular polarization (RHCP) and fabricated in two separate layers. A broadband impedancebandwidth of 13.9% and a RHCP axia...

Microstrip patch antennas represent one family of compact antennas that offer a conformal nature and the capability of ready integration with communication system’s printed circuitry. In this project, a 2.4 GHz circular polarization microstrip antenna is designed, constructed and measured. The selected microstrip antenna is a dual –fed circular polarized microstrip antenna. The antenna consists...

In this paper, we will introduce a cocentered orthogonal loop and dipole antenna (COLD) to a borehole radar system. With the cocentered orthogonal loop and dipole antenna, we could obtain additional information on polarization state of arrival waves in the borehole radar using * optical modulators. We set the proposed antenna in a borehole actually, and made electromagnetic waves with known pol...

Active antennas (AAs) are a class of radiation system that integrates an antenna and backing active circuits which results in considerable reduction in complexity of the matching networks and filters [1]. This is done by carefully designing the radiating element to provide proper load for active elements. Hummer and Chang have investigated active antenna elements using a microstrip patch antenn...