Research On Non-intrusive Human Body Information Perception Technology Based On Wireless Signal

With the rapid development of information technology,the coverage of wireless networks is getting wider and wider,and deployment is becoming more and more convenient.This has also makes more and more researchers using wireless signals to conduct a series of related application research.In medical and other applications,the detection of human breathing and sleep status is of great research value.The traditional detection of human breathing and sleep requires the body to wear relevant sensors,or based on video images.These traditional techniques have caused patients with problems of mobility difficulties or violation of patient privacy.In this paper,the channel state information of the physical layer in the wireless signal is used to design a non-invasive method for detecting human respiratory frequency and sleep state,which effectively overcomes the problems caused by traditional detection methods.The main work of this paper includes the following aspects:(1)Summarize and analyze the traditional human body information detection technology,point out the problems and deficiencies of the traditional methods,and analyze the research progress of human information detection using wireless signals;(2)Introduce the specific principles of RSSI and CSI,as well as the acquisition methods of CSI,and briefly introduce the commonly used CSI data processing algorithms;(3)Build a non-intrusive human body information sensing platform based on CSI,collect CSI data,and extract CSI amplitude information for respiratory and sleep data analysis;(4)Study the CSI data preprocessing method,combined with discrete wavelet transform,so that the frequency of the signal remains within the normal respiratory frequency range,and the accuracy of respiratory frequency detection is improved;(5)Converting the collected time-series sleep CSI amplitude data into timeseries sleep variance energy data to realizing simple sleep behavior recognition,and detecting respiratory frequency when the sleep state is stable;(6)Different comparative experiments were conducted to analyze the effects of different factors on the detection of respiratory and sleep states,and to verify the effectiveness of the non-invasive information detection method based on wireless signals.