Abstract illustration of microwave radiometry in medical diagnostics.

Microwave Radiometry: The Future of Medical Diagnostics?

Soraya Malik in Health & Wellness August 2025 • 3 min read.

"Explore how advancements in antenna technology are revolutionizing medical diagnostics, offering deeper insights and improved patient care."

Microwave radiometry (MR) is transforming medical diagnostics by harnessing the power of microwave radiation emitted from the body. Unlike methods that require external energy sources, MR passively detects subtle temperature variations within tissues, offering a non-invasive window into the body's inner workings. This capability is particularly valuable because temperature changes can be early indicators of various medical conditions.

The fundamental principle behind MR lies in the fact that all biological objects (BO) with a temperature above absolute zero emit microwave radiation. By measuring the intensity of this radiation, clinicians can determine the temperature of the underlying tissues. This technique, known as radio-heat location, provides a functional diagnostic approach distinct from traditional imaging methods like infrared thermography.

One of the key advantages of MR is its ability to penetrate deeper into the body than infrared methods. While infrared thermography is limited to surface measurements, MR can detect thermal anomalies several centimeters beneath the skin. This makes it particularly useful for identifying conditions such as breast cancer, melanomas, and monitoring brain temperature. The core of the MR system includes an antenna applicator that captures the faint microwave signals and a highly sensitive radiometric receiver that amplifies and processes these signals.

How Do Microwave Radiometers Work?

Abstract illustration of microwave radiometry in medical diagnostics.

The process begins with the antenna applicator, which is designed to capture microwave radiation emitted by the body. The power of the radiation is directly related to the brightness temperature (BT), a measure that reflects the thermodynamic temperature of the tissue. The relationship between these factors is described by the equation:

T_rad = ∫ T(r)W(r)dV

T_rad represents the brightness temperature.
T(r) is the thermodynamic temperature at a specific location within the body.
W(r) is the radiometric weighting function, which describes the antenna's sensitivity to radiation at different points.
The integral is calculated over the volume (V) of the biological object.

The radiometric weighting function, W(r), is crucial for understanding the spatial sensitivity of the antenna. It is defined as:

The Future of Medical Radiometry

The development and refinement of printed and textile antennas are significantly reducing the cost and complexity of MR technology. This miniaturization paves the way for creating personalized diagnostic tools and integrating MR into advanced medical systems, such as diagnostic apparel, radiological equipment, and medical robots. These advancements promise to enhance early disease detection, improve treatment monitoring, and ultimately transform patient care.

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

This article is based on research published under:

DOI-LINK: 10.1007/s10527-018-9820-1, Alternate LINK

Title: Antenna Applicators For Medical Microwave Radiometers

Subject: Medical Laboratory Technology

Journal: Biomedical Engineering

Publisher: Springer Science and Business Media LLC

Authors: M. K. Sedankin, V. Yu. Leushin, A. G. Gudkov, S. G. Vesnin, I. A. Sidorov, S. V. Agasieva, L. M. Ovchinnikov, N. A. Vetrova

Published: 2018-11-01

Everything You Need To Know

What is Microwave Radiometry, and how does it work?

Microwave radiometry (MR) is a medical diagnostic technique that utilizes microwave radiation emitted naturally from the human body to measure tissue temperatures. Unlike techniques that use external energy sources, MR passively detects subtle temperature variations, which can be early indicators of medical conditions. This non-invasive approach allows clinicians to gain insights into the body's inner workings without introducing any form of radiation or energy.

Why is Microwave Radiometry important for medical diagnostics?

MR is significant because it provides a non-invasive way to detect thermal anomalies deep within tissues. The ability of MR to penetrate deeper than methods like infrared thermography enables the identification of conditions such as breast cancer and melanomas. By measuring the brightness temperature (BT), clinicians can assess the thermodynamic temperature of tissues. This capability is crucial for early detection and monitoring of diseases, leading to improved patient outcomes. The use of MR also avoids the risks associated with other imaging modalities that might require exposure to radiation.

How does a Microwave Radiometer function to measure tissue temperature?

A Microwave Radiometer works by capturing microwave radiation naturally emitted by the body using an antenna applicator. This device is designed to detect faint microwave signals. The power of the radiation is directly related to the brightness temperature (BT), which represents the thermodynamic temperature of the tissue. These signals are then processed to determine tissue temperatures. The radiometric weighting function, W(r), is used to understand the antenna's sensitivity to different points within the body. This process allows for non-invasive monitoring of internal body temperatures, enabling the detection of thermal anomalies associated with various medical conditions.

Can you explain the equation used in Microwave Radiometry?

The equation T_rad = ∫ T(r)W(r)dV is central to understanding how MR measures tissue temperature. T_rad represents the brightness temperature, which the MR system measures. T(r) is the thermodynamic temperature at a specific location within the body. W(r) is the radiometric weighting function, and it is the antenna's sensitivity to the radiation at a specific point. The integral is calculated over the volume (V) of the biological object. This equation shows the relationship between the measured brightness temperature and the actual temperature distribution within the body, which helps clinicians understand the health of the underlying tissues.

What are the future implications of Microwave Radiometry?

The refinement of printed and textile antennas is poised to transform medical radiometry by reducing the cost and complexity of Microwave Radiometry (MR) technology. This miniaturization opens opportunities for creating personalized diagnostic tools and integrating MR into advanced medical systems, such as diagnostic apparel and medical robots. These advancements promise to enhance early disease detection, improve treatment monitoring, and ultimately transform patient care. The integration of MR into everyday medical tools is expected to make diagnostics more accessible and efficient.