A Remote Compact Sensor for the Real-Time Monitoring of Human Heartbeat and Respiration Rate

A remote compact sensor system for the detection of human vital signs (heartbeat and respiration rate) is presented. The frequency band of 24 GHz is employed for remote sensing. For the compact size, the developed sensor uses a circularly polarized electromagnetic wave with a single antenna. The sensor system is composed of radio-frequency circuits, a signal conditioning block, a data-acquisition unit, and a signal-processing part. The peak detection of the power spectral density with a tracking algorithm is utilized for the real-time detection of human vital signs. The measurement result is compared with the commercial fingertip sensor. The comparison result shows excellent agreement.