Patent ID: 9568634
Date: 2017-02-14
CPC Classifications: G01V

Claim:
1. A logging tool having an antenna for transmitting or receiving signals with a magnetic field component orthogonal to a longitudinal tool axis, the antenna including at least two portions arranged on opposite sides of the longitudinal tool axis, the antenna comprising: a conductive wire that forms at least four separate multi-loop windings in series between a first driving terminal that provides a positive voltage and a second driving terminal that provides a negative voltage equal in magnitude to the positive voltage, the at least four windings include at least two windings on each of the at least two portions, the conductive wire sustaining a voltage distribution along its length during operation of the antenna, the voltage distribution being symmetric about a grounded midpoint of the conductive wire, and the windings being arranged so that each winding on each portion of the antenna is matched by another winding on that portion having an equal and opposite voltage distribution.