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Article: Active antennas. (electronic warfare) (EW Reference & Source Guide: Technical Manual)
- Article from:
- Journal of Electronic Defense
- Article date:
- January 1, 1994
- Author:
CopyrightCOPYRIGHT 1994 Horizon House Publications, Inc. This material is published under license from the publisher through the Gale Group, Farmington Hills, Michigan. All inquiries regarding rights should be directed to the Gale Group. (Hide copyright information)
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An active antenna is simply an antenna that consumes power, other than from the signal environment, in order to function. This briefing treats the classic case of an electrically short monopole antenna element integrated with a high impedance amplifier and intended for receiving only.
We consider the use of active antennas whenever we require electrically short (antenna length |much less than~ wavelength) elements and they must work over a broad range of frequencies without tuning. They have traditionally been used in the VLF-HF frequency ranges but are increasingly being employed up through UHF. Applications include communications, EW, navigation and scientific ...