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Active antenna

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


Papers
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Patent
21 Aug 1998
TL;DR: In this paper, a structure of an active antenna system of a mobile and a satellite navigation method using the system is presented, in which beams are formed and then directed by using sub-array concept, the tracking accuracy becomes to high by using double beam satellite tracking mode for tracking the satellite.
Abstract: This invention relates to a structure of an active antenna system of a mobile and a satellite navigation method using the system. The present invention provides a structure of an active antenna system of a mobile and a satellite tracking method using the system, in which beams are formed and then directed by using sub-array concept, the tracking accuracy becomes to high by using double beam satellite tracking mode for tracking the satellite, tracking loss is reduced and positions are more accurately tracked during movement using an absolute steering sensing mode.

40 citations

Patent
11 Feb 1987
TL;DR: In this article, an improved phased array active antenna transmit-receive means utilizing a multiplicity of individual transmitreceive cells positioned in an array format upon a common wafer of semiconductor material.
Abstract: An improved phased-array active antenna transmit-receive means utilizing a multiplicity of individual transmit-receive cells positioned in an array format upon a common wafer of semiconductor material. Each transmit-receive cell, comprises a multiplicity of redundant, integrated circuit, electronic devices implanted upon the common semiconductor substrate. The transmit-receive cells utilize novel mitered mechanical switches to permanently interconnect individual electronic devices into either transmit or receive circuits during the fabrication and test of the transmit-receive cells. Radio frequency and direct current input and output vias formed from a novel metal evaportion technique connect the devices upon the surface of the common semiconductor wafer to underlying, insulated direct current distribution circuits and a radio frequency manifold. This array of improved phased-array active antenna transmit-receive means comprised of transmit-receive cells sharing common central processing means, logic control and heat dissipation means results in a significant reduction in the size and weight of the standard phased-array active antenna system. This significant reduction in antenna system size and weight is very important in broad band electronic countermeasure systems or narrow band phased array active antenna radar systems as used in advanced tactical fighters, or space applications.

40 citations

Journal ArticleDOI
TL;DR: In this paper, a broadband high-efficiency circularly polarized (CP) active integrated antenna, and a broadband CP active array at 2 GHz, were realized by directly integrating the broadband CP antenna with the class-E PA.
Abstract: This paper presents a broadband high-efficiency circularly polarized (CP) active integrated antenna, and a broadband CP active array at 2 GHz. To realize the broadband CP antenna, a circular patch is aperture coupled by crossed slots in the ground plane, which are fed by an L-shaped microstrip feed line below the ground. The antenna is designed to serve the functions of both a radiator and a harmonics-terminated load for class-E high-efficiency power-amplifier (PA) integration. The broadband CP active antenna is realized by directly integrating the broadband CP antenna with the class-E PA. It achieves a 9% bandwidth (1.84-2.01 GHz) for axial ratio (AR) below 3 dB, and a 12% bandwidth for power-added efficiency (PAE) over 60%. To form the broadband CP active array, four active antenna elements are sequentially rotated, and each element is directly integrated with broadband class-E PA. A low-cost printed-circuit-board technology is employed in fabrication and a pseudomorphic high electron-mobility transistor is used. A peak drain efficiency of 71.5% for the class-E amplifier is measured at 1.95 GHz. The active array achieves a peak-effective radiated power of 39.7 dBm, and PAE is over 50% within a 22.6% bandwidth (1.72-2.16 GHz). The AR is below 3 dB over a 27% bandwidth (1.72-2.26 GHz).

39 citations

Patent
21 Mar 1985
TL;DR: An active antenna for the reception of long-, medium-, short-and ultra-short wave broadcasts is arranged in a rear window of a motor vehicle equipped with a boundary conductor enclosing an array of heating elements as mentioned in this paper.
Abstract: An active antenna for the reception of long-, medium-, short-and ultra-short wave broadcasts is arranged in a rear window of a motor vehicle equipped with a boundary conductor enclosing an array of heating elements. The reception of long-, medium- and short-wave signals is made by means of an elongated flat antenna element which is arranged in the window on a free area above or below the heating elements, and the reception of the ultra-short wave signals is effected by the array of heating elements. An antenna amplifier includes a linear amplifying stage connected to the flat antenna element, an amplifying branch circuit connected to the array of heating elements and a common ground terminal connected to the boundary conductor. A frequency separator has two inputs connected, respectively, to the output of the amplifying stage and of the branch circuit, and an output connected via an antenna cable to a conventional radio receiver.

39 citations

Journal ArticleDOI
01 Jan 1994
TL;DR: In this paper, the radiation characteristics of a probe-fed microstrip patch loaded with a varactor diode were investigated, and it was shown that large effective bandwidths can be achieved using varactor diodes, although at the expense of reduced antenna efficiency and increased cross-polarisation levels.
Abstract: A thorough investigation of the radiation characteristics of a probe-fed microstrip patch loaded with a varactor diode is presented. The theoretical analysis used to model this structure incorporates the full-wave spectral domain integral technique in conjunction with an equivalent circuit model of the varactor diode. Attachment modes are used to accurately model the current through the feed and load. Very good agreement between theory and measurement was obtained. From this investigation, the advantages and drawbacks of using varactor diodes to improve the radiation characteristics of a microstrip patch antenna were established. It was shown that large effective bandwidths can be achieved using varactor diodes, although at the expense of reduced antenna efficiency and increased cross-polarisation levels.

39 citations


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Performance
Metrics
No. of papers in the topic in previous years
YearPapers
202148
2020113
2019123
201898
201789
2016102