Quantification of electromagnetic absorption in humans from body-mounted communication transceivers

The internal electric (E) field and energy deposition in a full-size adult male mannequin in the immediate vicinity of 1.5 W body-mounted communication transceivers have been measured. Transceivers operating at the four frequencies 50, 150, 450, and 800 MHz, and placed at various locations vis-à-vis the body were used. The mannequin was filled with two-thirds muscle-simulant biological phantom mixtures at each of the four frequencies. The complex permittivities (ε^*) of these mixtures were confirmed by measurement. The internal E-field distribution was measured by three-dimensional implantable E-field probes. Relatively superficial energy depositions were obtained at points close to the location of the transceiver antenna for the two higher frequencies with energy depositions typically less than 1-2 W/kg. Considerably reduced energy depositions were measured at the two lower frequencies on account of in-depth and wider dissemination of the absorbed energy and the relatively high ε^*of the tissues which results in an increased shielding of the body.