JOURNAL OF COMMUNICATIONS (JCM)
ISSN : 1796-2021
Volume : 4    Issue : 4    Date : May 2009

Improving Medium Access in Through-The-Earth VLF-LF Communications
Vanessa Bataller, Antonio Muñoz, Pilar Molina Gaudó, Arturo Mediano, José Antonio Cuchí, and
José Luis Villarroel
Page(s): 284-294
Full Text:
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Abstract
In order to improve the communication range of Through-The-Earth (TTE) radio using electrodes,
the impedance load seen by power stage load must be minimized. This impedance depends on
the wires, the electrode contact and the path between the electrodes (earth). Of the three elements,
we cannot influence the earth impedance. The wire impedance can be minimized employing short
cables and avoiding coiling them. This paper presents a method for characterizing the electrode
contact impedance and provides suggestions to minimize it. Therefore some impedance
measurements with several electrodes and a variety of contact conditions have been performed in
order to improve our knowledge of medium access. To further prove the results measurements
have been made with a voice radio application.

Index Terms
TTE, electrode impedance, medium access, earth impedance