Non-contact respiratory monitoring radar system based on micro-Doppler effect

Breathing often reflects people’s physical condition, such as sleep apnea is closely related to cardiovascular and cerebrovascular diseases, sleep quality is also closely related to breathing. A non-contact respiratory monitoring device is designed to monitor people ‘s breathing for a long time, so that people can understand their own breathing conditions and prevent some potential diseases. System hardware mainly includes LimeSDR, 2.4G directional antenna, power amplifier, low noise amplifier and host computer. The software is GNURadio for data visualization and data extraction. A flow chart is built on GNURadio to process the signals transmitted and received by LimeSDR, and the human respiratory data is obtained according to the micro-Doppler effect. The effective detection distance of the device is about 1 meter, and the accuracy rate is 93.75%. Compared with the traditional contact breathing monitoring, the device avoids the discomfort when people are attached to the sensor. This device is mainly used for sleep monitoring, which is small in size and easy to operate, making it more suitable for individuals and families, and has great market prospects.