Non-invasively Active Near-field Probe Antenna Design for Subcutaneous Temperature Measurement

Abstract

The aim of this study is to develop an active near-field probe antenna for noninvasive temperature measurement of subcutaneous muscles. The active part is a low noise amplifier designed using ATF-54143 HEMT device placed on one side of the ground plane. A planar-type patch placed on the other side of the ground plane was designed in the 1.575 GHz GPS band to receive the thermal radiation power that emanates from inside a human body to retrieve temperature information. The designed active antenna is pasted on the skin for probing the radiated power from the subcutaneous muscles of human body. Agar material was developed to fabricate a phantom model to replicate electrical characteristics of a human body during testing. This addition of the LNA can achieve gain 13 dB and noise figure less than 1 dB. The study demonstrates using the active probe connected to the radiometer can predict the output voltage of the different temperature inside the body.