In this paper, the authors propose a circularly polarized printed antenna combining a slot array antenna and a patch antenna, with dual-band operation. The proposed antenna has good isolation performance, is compact, and has simple configuration. This antenna is composed of two parts, a patch antenna (for Rx) on the top, and a slot array antenna (for Tx) on the bottom, respectively. The element...

this article presents an overview of the recent Frequency dependent and Frequency independent antenna theory. An antenna is defined by Webster’s Dictionary as “a usually metallic device (as a rod or wire) for radiating (transmitting) or receiving radio waves or EM wave.” The IEEE Standard Definitions of Terms for Antennas (IEEE Std 145–1983) defines the antenna as “a means for radiating or rece...

This paper presents the results of an interference localisation trial using an experimental adaptive antenna array currently under development. The prototype adaptive antenna array was driven through a field of RF transmitters and the direction of arrival (DOA) of multiple RF signals at various positions of the vehicle were estimated. From these DOA measurements the transmitter locations were e...

In this paper, the performance of a smart antenna system based on a linear array is evaluated. The results presented here include the antenna pattern. This procedure can reduce the interference level in a cellular communications system. Key-words: Smart Antennas, linear array, switched-beam, adaptive array, SDMA.

In the context of passive sources localization using antenna array, the estimation accuracy of elevation, and azimuth are related not only to the kind of estimator which is used, but also to the geometry of the considered antenna array. Although there are several available results on the linear array, and also for planar arrays, other geometries existing in the literature, such as 3D arrays, ha...

Diversity reception is a widely used technique in radio communications to reduce signal fading due to complex propagation environments. Fading is caused by multipath propagation of the radio signal in complex environments, which in practice are either downtown areas in large cities or indoor environments. This presentation is focused on the design problem of an antenna array, which could be use...

according to high costs of phase shifters in antenna arrays, new methods for beam steering without phase shifter were introduced. frequency diverse array (fda) concept is another approach to beam steering problem. in this structure, the subsequent antenna elements are fed with stepped discrete frequencies causing continuous scanning of space in time. so a range-angle dependent scanning is made ...

Antennas integrated with active circuitry are usually referred to as active antenna arrays. The integration can be done at different levels, depending on the goal and application. For example, a low-noise amplifier (LNA) is often integrated directly with the antenna for reduced loss and therefore decreased noise figure. Another example is the integration of power amplifiers with antenna arrays ...