Design of a portable multi-physiological parameter detector
A novel portable head-mounted detector is designed to obtain the multi-physiological parameters,such as electrical impedance,blood oxygen,heart rate and body temperature.To address the issues such as narrow excitation frequency range,low accuracy and long detection time in the existing impedance detectors,the developed detector adopts 4-electrode measurement scheme,using a direct digital frequency synthesizer and Howland current source to generate sinusoidal excitation currents through the human body,employing AD8302 gain phase detector chip from Analog Devices Inc.,along with accompanying algorithms to calculate the amplitude and phase angle of the body's impedance,which significantly enhances detection accuracy and efficiency.To further minimize system errors,an analog switch circuit is designed in conjunction with high-precision sampling resistors and phase-shift capacitors for system parameter self-calibration.Experimental results reveal that within the detection frequency range of 10 kHz to 1 MHz,the average detection errors for impedance magnitude and phase are less than 0.5%and 0.59°,respectively,with maximum detection errors less than 1.54%and 1.38°,respectively,demonstrating superior performance than impedance detection schemes based on the TI company's AFE4300 chip.Additionally,the device integrates modules for the detection of blood oxygen,heart rate,and temperature.Human body experiments also verified its superiority in accuracy and effectiveness of multi-physiological parameter detection.
NETL
NSTL
万方数据
维普
