Active antenna

About: Active antenna is a research topic. Over the lifetime, 2246 publications have been published within this topic receiving 26493 citations.

Article shelf equipped with electromagnetic induction antenna

Abstract: PROBLEM TO BE SOLVED: To detect existence of a storage container by means of a passive antenna and an active antenna, prevent irregularity in a magnetic field between the passive antenna and the active antenna by a shelf board part formed of the material other than non-metal, and select a shelf to be detected by providing a switch on the antenna SOLUTION: This shelf comprises support parts, and shelf board parts placed in a horizontal state between the support parts Conductor is wound at least around part of the shelf to provide the passive antenna The active antenna to induce a magnetic flux is provided close to the passive antenna As the storage container provided with a transponder function is placed on the shelf board part, if the storage container exists or not is detected by the passive antenna and the active antenna The shelf board parts are formed of the material other than metal plates for preventing irregularity in the magnetic field between the passive antenna and the active antenna COPYRIGHT: (C)2004,JPO

A GPS+GLONOSS active antenna for extremely high temperature aerospace applications

Abstract: Global Positioning System (GPS) and GLONOSS positioning systems have lot of applications for navigation in various aerospace systems [1]. The GPS system involves a GPS antenna, a low noise amplifier, receiver and signal processor. Since GPS signals are inherently weak, a high gain but low profile active antenna is desirable for aerospace applications. Similar requirements apply for a GLONOSS antenna. The antenna also needs to meet the environmental specifications and also should be able to operate at stringent environmental conditions. The antenna also needs to be rugged and should withstand vibrations. A common active antenna assembly which works in both bands, has been developed for such application. This paper describes the design, assembly and electrical performance.

Aperture-coupled printed antenna for MMIC applications

Abstract: Experimental results of an aperture-coupled microstrip antenna, fed from a Transmit/Receive (T/R) case are presented. First the authors show graphical design curves, based on extensive measurements, which enable one to choose the geometrical parameters of the radiator according to desired frequency and bandwidth. Then same experimental results of an X-band active antenna are shown. >

Very wide band active antenna for passive radar

Abstract: The present invention relates to the field of passive VHF-UHF radars. It relates more particularly to the construction of omnidirectional VHF-UHF antennas, with wide passband, that can operate in an array without adversely affecting their radiation patterns. The invention consists of a dual-band antenna structure operating on two sub-bands of wide frequencies, and consisting of radiating elements forming a sub-antenna with minimum diffraction operating in the high sub-band, UHF, and a sub-antenna with minimum diffraction operating in the low sub-band, VHF, each element being brought into service or taken out of service separately as a function of the sub-band utilized. The output of the antenna is linked to the input of an amplifier with low wide band noise, placed as close as possible and exhibiting a high-impedance input and an output equal to the impedance of the transmission line through which it is linked to the receiver, the sub-antenna dedicated to the low sub-band comprising low-pass filters arranged so as to prevent the operation of this element when the element dedicated to the high sub-band is in service.