Key result
A compact wireless 2.4 GHz RF sensor placed 20 mm away from a human body can accurately detect heartbeat and respiration signals by utilizing input impedance variation.
A novel 2.4 GHz wireless RF sensor can accurately detect heartbeat and respiration signals from 20 mm away without contact.
May enable contactless vital sign monitoring; leaves open prospective clinical validation before adoption.
This paper describes a compact and novel wireless vital sign sensor at 2.4 GHz that can detect heartbeat and respiration signals. The oscillator circuit incorporates a planar resonator, which functions as a series feedback element as well as a near-field radiator. The periodic movement of a human body during aerobic exercise could cause an input impedance variation of the radiator within near-field range. This variation results in a corresponding change in the oscillation frequency and this change has been utilized for the sensing of human vital signs. In addition, a surface acoustic wave (SAW) filter and power detector have been used to increase the system sensitivity and to transform the frequency variation into a voltage waveform. The experimental results show that the proposed sensor placed 20 mm away from a human body can detect the vital signs very accurately.
No takes yet. Share an insight, caveat, or question.
Kim et al. (2012) studied Vital sign monitoring. Wireless RF sensor at 2.4 GHz was evaluated on Detection of heartbeat and respiration signals. A compact wireless 2.4 GHz RF sensor placed 20 mm away from a human body can accurately detect heartbeat and respiration signals by utilizing input impedance variation.
Synapse has enriched 4 closely related papers on similar clinical questions. Consider them for comparative context: