Location determination is performed using a transmitter including an elongated generally planar loop antenna defining an elongation axis. The elongation axis is positioned along at least a portion of a path. A magnetic field is then generated which approximates a dipole field. Certain characteristics...http://www.google.fr/patents/US7209093?utm_source=gb-gplus-shareBrevet US7209093 - Locating technique and apparatus using an approximated dipole signal
Locating technique and apparatus using an approximated dipole signal
