A Computational Approach to Increasing the Antenna System's Sensitivity in a Doppler Radar Designed to Detect Human...

Area of Science:

• Electromagnetics
• Biomedical Engineering
• Radar Systems

Background:

• Doppler radar studies chest movements for vital sign detection via S21 transmission coefficient phase shifts.
• Detecting life signs is challenging with obstructions, and system sensitivity depends heavily on monitoring systems and antennas.

Purpose of the Study:

• To computationally extract an empirical law correlating S21 phase shift to reception sensitivity.
• To identify key parameters influencing vital sign detection sensitivity in Doppler radar systems.

Main Methods:

• Investigated a 1-20 GHz frequency range using dipole or Yagi antennas.
• Modeled a moving chest surface (3 mm path, 0.3 mm steps) in a computational space.
• Utilized statistical multiple regression to derive an empirical relationship.

Main Results:

• Established an empirical law linking phase shift to reception sensitivity based on four parameters.
• Identified frequency, antenna characteristics, electric field distribution, and material dielectric properties as critical factors.
• Simulations demonstrated the relationship for a simulated respiration movement.

Conclusions:

• The derived empirical law enables the development of continuous-wave bio-radar Doppler systems.
• This approach allows for controlled and improved sensitivity in detecting vital signs.
• The findings provide a foundation for more robust non-invasive monitoring systems.