Effects of dielectric parameters of human body on specific absorption rate for ingestible wireless device at operating frequency of 430 MHz

The radiation characteristics of Ingested Wireless Device (IWD) in two realistic human (male and female) body models whose dielectric values had variability up to 20% were compared. Results showed that variation of signal intensity near the surface of abdomen was less than 2.5 dB. Specific absorption rate (SAR) maximum values increased with the increment of conductivities of human body tissues and usually decreased with the increment of relative permittivities. An increment of up to 20% in conductivities and relative permittivities alone or simultaneously always caused a variation of SAR less than 10%. As far as the compliance of safety was concerned, the maxima of averaged-1g and averaged-10g SARs could reach 3.16 and 0.89 W/kg at the input power of 25 mW.