RF sensor design and performance analysis for diagnosis of anomalies using S-parameters: a review

Microwave technology provides a non-invasive and safe method for emitting signals and penetrating dielectric materials, making it extremely suitable for medical and industrial applications such as detection, diagnosis, monitoring, and classification. Due to their electromagnetic behavior with advantages like portability, affordability and advancements in computational power, microwaves have gained significant popularity in the development of biomedical sensing and imaging systems. These systems promise to support and replace established diagnostic techniques. This review presents an overview of development in the medical use or patient care of microwaves. It highlights significant progress in clinical tools aiming at diagnosing and classifying brain strokes, diagnosing breast cancer, monitoring blood glucose levels and hydration level detection. The discussion covers technical components such as antennas, sensors, and changes in S-parameters. This paper also shows the comparison between different sensors in terms of fractional bandwidth percentage, specific absorption rate, and gain. Lastly, it addresses the ongoing challenges in clinical adoption of microwave technologies for non-invasive diagnosis of various diseases by RF sensors.