Widebanding Techniques for VHF Antennas - I

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.

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Document Details

Document Type
Technical Report
Publication Date
Sep 30, 1992
Accession Number
ADA259301

Entities

People

  • Ramakrishna Janaswamy

Organizations

  • Naval Postgraduate School

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Antennas
  • Broadband
  • Coefficients
  • Computers
  • Diameters
  • Elements
  • Engineering
  • Frequency
  • Frequency Bands
  • Impedance
  • Monopole Antennas
  • Power Gain
  • Radiation
  • Radiation Patterns
  • Resistance
  • Topology
  • Transducers

Readers

  • Electromagnetic Wave Scattering and Antenna Radiation Engineering
  • Microwave Engineering.