The Design Of The Radar-based Non-contact Life-detection Signal Processing System Based On DSP

The technology of radar-based non-contact life-detection develops rapidly recently, and the theory is that using microwave beams to illuminate the human subject, then the reflected wave will be modulated by the surface movement resulting from the physical activity. By this way, some parameters of the reflected wave, such as frequency and phase will be changed. Using some special hardware circuits and software to detect these changes, then the life parameters such as respiration rate and heartbeat rate will be extracted from those changes.Now in our lab the signal sampling and processing system of radar-based non-contact life-detection system is mainly composed of a computer and a USB data sampling card. The analog signals, received by radar ahead and processed by pro-processing system, are converted to digital signals by the card, and then the computer reads this digital signals, after analyzing and processing, the signal will be displayed on the computer screen. The computer also takes the responsibilities of sampling control.Based on DSP this signal processing system can take the place of the computer and USB data sampling card to play the role of signal sampling, analyzing and display. Using this unit to compose the radar-based non-contact life-detection system, not only takes the advantages of small size, light weight, low power consumption, but also easy to carry.The following research work has been carried out in this thesis:1. Designed the hardware platform with DSP of TI product TMS320VC5410A, A/D converter of AD product AD7707 and MCU C8051F120. After being pro-processed the analog signal is converted to digital signal by AD7707, and through the serial port DSP read this signal. Using some signal processing algorithm to analyze it, then the result is sent to MCU through HPI to display on the liquid crystal display.2. Programmed the software application system. Based on assembly language and the special TMS320C54x DSP instructions this system can be used to sample two channels analog signals, store the data, analyze the data and interrupt the MCU to display the result.3. Designed the scheme of serials of exercise experiments to evaluate the stability of the hardware circuit and software system. Altered the amplitude, frequency of the source signal, signal gain and the sampling frequency, then observed the wave in the CCS. Used Matlab software package to assist algorithm development. Constructed the whole life-parameter detecting system to sample real time respiration signals and body movement signals, obtained serials of experiments data.Innovations in the thesis are listed below:1. For the first time, based on DSP, with a new method constructed a real time signal sampling, processing and display platform. This platform can be used to take place of the computer and USB data sampling card.2. Accomplish a set of software system to match the hardware circuit, and this system can be used in the radar-based non-contact life-parameters detecting system. The whole size is reduced and very convenient to be carried around.In this study, a hardware platform and software system is designed, and a...