Vital Signs Detection by a 24 GHz Radar Sensor Operating in Linear/Circular Polarization in the Presence of...

Area of Science:

• Biomedical Engineering
• Electromagnetics
• Radar Systems

Background:

• Remote vital signs monitoring is crucial for healthcare.
• Environmental clutter can significantly impede radar-based vital signs detection.
• Polarization techniques in radar offer potential solutions for improved signal discrimination.

Purpose of the Study:

• To develop and evaluate a 24 GHz radar system for remote vital signs monitoring.
• To analyze the performance differences between linear polarization (LP) and circular polarization (CP) radar in cluttered environments.
• To demonstrate the advantages of CP radar for robust vital signs detection.

Main Methods:

• Development of a 24 GHz radar system with LP and CP horn antennas.
• Utilizing a geometric optics (GO) model to simulate clutter scenarios.
• Employing analytical modeling, numerical computations, and experimental investigations.
• Simulating environmental disturbance using vibrating metallic panels.

Main Results:

• Circularly polarized (CP) radar sensors showed enhanced ability to discriminate vital signs from environmental clutter.
• LP radar performance was significantly degraded by simulated metallic panel vibrations.
• CP radar sensors exhibited robustness in detecting respiratory and cardiac activity even in the presence of clutter.

Conclusions:

• CP radar technology offers a significant advantage over LP radar for reliable vital signs monitoring in challenging environments.
• The developed 24 GHz radar system, particularly with CP, is suitable for domestic and hospital applications.
• This research validates the effectiveness of CP radar for overcoming environmental interference in vital signs detection.