-In this paper, we have presented how the capacity of cellular system can be enhanced by using Space Division Multiple Access (SDMA) with directive antenna in mobile communication systems. One of the biggest draw back of wireless environment is the limited bandwidth. However, the users sharing this limited bandwidth have been increased considerably. SDMA is a technology by which the capacity of...

| If two in-phase plane waves arrive at an antenna from di erent directions, the resulting signal is not necessarily the coherent sum of the two incoming signals. This is due to the fact that the antenna radiation pattern is actually a complex quantity containing amplitude and phase properties. Thus, it can be stated that antenna phase characteristics may vary as a function of direction. In fre...

5.1 INTRODUCTION MIMO wireless systems have demonstrated the potential to increase communication spectral efficiency in a rich multipath environment. From an antennas perspective, different array configurations and types of element have been proposed and analyzed for MIMO links. Nowadays in military and commercial applications there have been ever growing demands for antennas. The standard dipo...

A low cost 4  4 butler matrix fed antenna array has been proposed for Ku band applications. At high frequencies, the ohmic and dielectric losses are high and also the undesired feed radiation is more in the case of microstrip line feed, therefore substrate integrated waveguide (SIW) has been used to feed the antenna elements. The implementation of SIW technology improved the radiation performa...

Abstract—The growth of portable wireless communication devices has pushed designers to design miniature size antennas. The most prized among miniature antenna choices is the micro-strip patch antenna. These antennas have significant advantages such as low profile, light weight, relatively low manufacturing cost, and polarization diversity. In this paper Genetic Algorithm optimization technique ...

A three-dimensional (3D) highly-directive emission system is proposed to enable beam shaping and beam steering capabilities in wideband frequencies. It is composed of an omnidirectional source antenna and several 3D gradient-refractive-index (GRIN) lenses. To engineer a broadband impedance match, the design method for these 3D lenses is established under the scenario of free-space excitation by...

Currently highly directive antennas on the market can range from as little as fifty dollars to a couple of hundreds of dollars. The gain of these antennas is between the ranges between 8dBi to 20dBi. A cheaper alternative with a similar gain characteristic can be developed to appeal to the consumers on the market. This project involves the designing, building, and testing of a highly directiona...

This paper presents an approach for a precise 2D-localization of a mobile station in indoor scenarios by one single base station only. In the approach both, the Direction of Arrival (DoA) and the Time of Arrival (ToA), are estimated using UWB beamformers at both sides of the link. The article describes the algorithm, as well as the required hardware. A duallinear polarized, directive UWB antenn...

in this paper a new low profile substrate integrated waveguide (siw) probe-fed h-plane horn antenna structure with improved gain is proposed. the proposed antenna consists of two waveguides including a rectangular and a taper one, in which both, first and third modes of the structure are simultaneously excited leading to a uniform field distribution along the radiating aperture of the antenna a...