Core temperature measurement by microwave radiometry

A 'double-container model' was used for core temperature (T _c) measurement by microwave emission radiometry (MR) of warm fluid inside a tube, placed in a container with a cooler fluid. The intensity of microwaves emitted from the warmer fluid inside the tube were measured using a MR metering device, consisting of an antenna linked to a low-noise radio frequency amplifier (bandwidth ∼500 MHz, centered at 4.0 GHz). Based on the MR measurements, a T _c prediction model was developed for measuring the temperature of fluid inside a tube, achieving a sensitivity of ±0.5°C at environmental temperature of 33-37°C.