A SAR-probe calibration system using reference dipole antenna in tissue-equivalent liquid

The SAR-probe is usually calibrated using a rectangular waveguide with a matching dielectric spacer below 3 GHz. However, the probe diameter is comparable with the cross-section area of the waveguide above 3 GHz and it can deteriorate the accuracy of the calibration. Therefore, there is an alternative method for calibrating the SAR-probe; relating the output voltage of the probe to the field intensity produced by a reference antenna in the tissue-equivalent liquid by two-antenna method. In this report, we have built a prototype of a calibration system and presented some calibration results of SAR-probe sensitivity using this method in conducting head-equivalent liquid at 2.45 GHz.