A CMOS Doppler radar sensor measured heart rates within 5 beats/min of ECG for 16 of 22 subjects at 0.5m, and respiration rates within 5 respirations/min of a belt for 18 of 22 subjects at 0.5m.
Observational (n=22)
Does a CMOS Doppler radar sensor accurately measure heart and respiratory rates compared to standard ECG and respiratory belts in human subjects?
A novel CMOS Doppler radar sensor can measure heart and respiratory rates without contact, showing moderate agreement with standard ECG and respiratory belts at close ranges.
A CMOS Doppler radar sensor has been developed and used to measure motion due to heart and respiration. The quadrature direct-conversion radar transceiver has been fully integrated in 0.25-mum CMOS, the baseband analog signal conditioning has been developed on a printed circuit board, and digital signal processing has been performed in Matlab . The theoretical signal-to-noise ratio (SNR) is derived based on the radar equation, the direct-conversion receiver's properties, oscillator phase noise, range correlation, and receiver noise. Heart and respiration signatures and rates have been measured at ranges from 0.5 to 2.0 m on 22 human subjects wearing normal T-shirts. The theoretical SNR expression was validated with this study. The heart rates found with the radar sensor were compared with a three-lead electrocardiogram, and they were within 5 beats/min with 95% confidence for 16 of 22 subjects at a 0.5-m range and 11 of 22 subjects at a 1.0-m range. The respiration rates found with the radar sensor were compared with those found using a piezoelectric respiratory effort belt, and the respiration rates were within five respirations per minute for 18 of 22 subjects at a 0.5-m range, 17 of 22 subjects at a 1.0-m range, and 19 of 22 subjects at a 1.5-m range.
Droitcour et al. (Wed,) reported a observational. CMOS Doppler radar sensor vs. Three-lead electrocardiogram and piezoelectric respiratory effort belt was evaluated on Heart rate and respiration rate accuracy compared to standard methods. A CMOS Doppler radar sensor measured heart rates within 5 beats/min of ECG for 16 of 22 subjects at 0.5m, and respiration rates within 5 respirations/min of a belt for 18 of 22 subjects at 0.5m.