Abstract
Expressions are derived for the surface current induced by vertical and
horizontal dipoles on a nearby infinite groundplane. The expressions are
obtained by means of the exact magnetic field. It is found that for a
vertical dipole the surface current density decays roughly as the
inverse of the distance from the source, while for a horizontal dipole
it decays as the inverse distance squared. The result furnishes an
explication for the empirical observation that antennas carrying mainly
horizontal currents tend to be less sensitive to the dimensions of a
finite groundplane than antennas carrying vertical currents. A formula
is given by means of which the groundplane current of a compound source
can be evaluated and controlled.
Original language | English |
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Pages (from-to) | 82 - 84 |
Number of pages | 3 |
Journal | IEEE Antennas and Wireless Propagation Letters |
Volume | 4 |
Issue number | 1 |
DOIs | |
Publication status | Published - 2005 |
MoE publication type | A1 Journal article-refereed |
Keywords
- antennas
- ground plane
- surface current
- antenna radiation patterns
- current density
- dipole antennas
- magnetic fields
- compound source
- groundplane current decay
- inverse distance square
- magnetic field
- small antenna element
- surface current density
- vertical-horizontal dipole