Body-worn antennas operate in combination with a direction finding processor to be able to detect the presence of electromagnetic radiation involved in communication as well as the direction of the source of the electromagnetic radiation. In one embodiment, a number of wide bandwidth antennas, 2 MHz...http://www.google.fr/patents/US6771224?utm_source=gb-gplus-shareBrevet US6771224 - Direction finding system using body-worn antenna
