Ukraine, Kyiv, PJSC "SPE "SATURN".

Temperature is often used among the information required to diagnose the state of a person’s internal organs, as pathological processes occurring in the human body are usually accompanied by thermal deviations not only on the surface but also inside the body. Modern medicine needs to improve non-invasive methods of measuring temperature deep in the human body for the purpose of early diagnosis and monitoring of various pathological processes. Medical radiothermography, in particular, allows non-invasive determination of the integral deep temperatures of internal organs.
The development of modern radiometric equipment involves solving such complex problems as ensuring high sensitivity of devices, matching the antenna to the biological object, ensuring the required penetration depth, and measuring absolute temperature with an error of at least 0.1°C. Given the importance of this problem, this paper demonstrates the approaches to the development of modern radiothermographs that the authors used in the process of creating a device for diagnosing breast temperature abnormalities.
The study considers the principles and schemes of construction of radiothermographic devices, requirements to the equipment as a whole, as well as to its main components. The authors conclude that it is optimal to use a modulation-compensation scheme of a radiometer for medical radiothermometry based on the measurement of two parameters: the integrated temperature and the integrated coefficient of reflection of electromagnetic waves from a biological object. A schematic diagram of a prototype radiothermograph, as well as its composition and design, is presented.
The approaches to the creation of modern radiothermographs presented in this work should be useful for developers of medical equipment for surgery, otorhinolaryngology, orthopedics, pediatrics, gynecology, etc., where measuring the distribution of patient body temperatures is of diagnostic value.

Keywords: microwave, radiometer, temperature, antenna, biological tissue, reflection, radiation.

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