Concept of a Microwave Heating Array Along with IR Radiometry for Measuring Regional Blood Perfusion

This paper presents the concept of applying an array of microwave heating (MWH) antennas for the measurement of skin perfusion through thermoregulatory temperature response, captured by the infrared (IR) thermal imaging. Each antenna element has a hole placed in it to allow for “multi-point” perfusion measurement. The thermal responses at the holes (points) are simultaneously measured by an IR camera. A microstrip-fed, 2 by 1 array of rectangular shape annular slot antennas, on a semi-flexible substrate, operating at 2.45 GHz, was designed. 10-mm diameter holes allow the IR measurement of the skin temperature. Two pairs of this array, side by side, were used for MWH and the control. Measurements performed on tissue phantom and lower arm demonstrate promising results, where about 1 W power per element is enough to raise the tissue temperature by a desirable 2°C per hole, within a reasonable time.