Advancements in Non-Contact Radar-Based Techniques for Vital Sign Detection – A Review

Regularly monitoring vital signs, including heart rate and respiration, is of utmost importance in identifying and predicting medical conditions that may impact a patient's overall health and well-being. This continuous monitoring allows for early detection and timely intervention, which can be critical in preventing the progression of medical conditions and improving patient outcomes. The detection techniques can be classified as non-contact based and contact based. Traditional contact-based techniques are less viable for long-term monitoring and can be less reliable for repeat measurements. Therefore, non-contact-based methods such as radar-based techniques have gained significant attention. This paper discusses various non-contact techniques for detecting human vital signs using radar. These techniques are based on the reflection of electromagnetic waves from the human body, which provides information about the vital signs. The paper focuses on the principles of radar operation for vital sign detection, including the different types of radar systems, such as CW, FMCW, UWB, and SFCW. The paper also highlights the advantages of non-contact radar-based techniques over traditional contact-based techniques for vital sign detection, such as the ability to monitor vital signs continuously without requiring direct contact with the patient. Additionally, the paper discusses and compares the state-of-the-art research done in non-contact radar-based vital sign detection, including signal processing techniques for accurate and reliable measurement of vital signs.