Accession Number : ADA259301


Title :   Widebanding Techniques for VHF Antennas - I


Descriptive Note : Technical rept. 1 Oct 1991-30 Sep 1992


Corporate Author : NAVAL POSTGRADUATE SCHOOL MONTEREY CA DEPT OF ELECTRICAL AND COMPUTER ENGINEERING


Personal Author(s) : Janaswamy, Ramakrishna


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a259301.pdf


Report Date : 30 Sep 1992


Pagination or Media Count : 38


Abstract : A straight wire antenna of fixed length is narrow band due to the rapid variations in its input impedance, and to a lesser degree, in its radiation pattern. A wire antenna is, however, lightweight, easy to fabricate and simple to mount on any platform. To make a wire antenna broadband, we need resistive and/or reactive loading along its length. In this report, we consider monopole antennas loaded with (a) modified Wu-King resistivity profile, and (b) complex lumped loads. A 1-m monopole antenna is considered over 30-90 MHz. Input impedance and radiation efficiency data for the two cases are generated by employing the moment method. Tuning networks are designed using the real frequency method of Carlin to maximize the power transfer from a 50 ohm source to the antenna. Overall performance of the antenna by taking into account the mismatch loss due to the tuning network and resistive loss due to the loading is studied.


Descriptors :   *BROADBAND ANTENNAS , INPUT , CONTROL , WIRE , VARIATIONS , PROFILES , PLATFORMS , VERY HIGH FREQUENCY , LENGTH , TUNING , LIGHTWEIGHT , MOUNTS , ELECTRICAL IMPEDANCE , MONOPOLE ANTENNAS


Subject Categories : Electrical and Electronic Equipment
      Radio Communications


Distribution Statement : APPROVED FOR PUBLIC RELEASE