| The new technology of non-contact life-parameter detection is relative to that of the normal contact one, which uses microwave beams to illuminate the human subject, whose 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. If these changes can be detected, the life parameters such as respiration rate and heartbeat rate will be extracted from those changes. The technology of non-contact life-parameter detection has been paid more attention to its breakthroughs in the field of medicine, especially in the field of military medicine. This technology can be used hi the realms of life-parameter detecting, wounded soliders searching and warding at wartime, psychoanalysing and other realms, it also can be used to locate the wounded in earthquake and avalanche.In practice, the dithering of non-contact life-parameter detection system made by our group is produced because of the environmentalfactors such as wind, vibration, motion and so on. The amplitude of the dithering signal is stronger than that of the life-parameter signal, which makes it difficult to extract the life-parameter signal. The interference produced by the dithering of this detecting system is called self-dithering interference relative to human life-parameter such as respiration and heartbeat. So it is necessary to find a way to constrain the self-dithering interference of the non-contact life-detection system and raise SNR so as to extract the life-parameter signal of human subject.According to those practical problems mentioned above, this subject mainly deals with problems as follow: 1) Carrying out lots of theoretical experiments and systematizing some theory knowledge of the detecting system. 2) Studying the correlativity between the referring signal and the primary signal of the adaptive filter.3) Studying the effects of constraining the self-dithering interference based on fixed step-size (FSS) and variable step-size (VSS) LMS algorithms. 4) Designing the subsystem including hardware and software, developing the software and optimizing the adaptive algorithms for constraining the self-dithering interference of the non-contact life-parameter detection system.During my studying of postgraduate, I have accomplished above-mentioned researches and results listed below: 1) Accumulated lots of experimental data of non-contact life-parameter detection system under different conditions, which is a good foundation for the next stage of this research.2) Brought forward the method of using adaptive processing to constrain the self-dithering interference.3) Brought forward the method of using acceleration sensor to detect the self-dithering interference as the referring signal of the adaptive filter.4) Compared the performances of adaptive algorithms based on FSSMS and VSSLMS, which is the basis of parameter-setting for applying adaptive processing to constrain the self-dithering interference in this subject.5) Constructed the mathematical model between the self-dithering interference and its radar return signal.6)Drew the conclusion of that there exists the correlativity between the self-dithering interference and its radar return signal.7) Drew the conclusion of that there exists the adding relation between the radar return signal of the self-dithering interference and the detecting signal. 8) Developed the software for constraining self-dithering interference of non-contact life-parameter detection system.There are three creative points in my research work: 1) Brought forward the method of using adaptive processing to constrain the self-dithering interference of the non-contact life-parameter detection system.2) Brought forward the method of using acceleration sensor to detect the self-dithering interference as the referring signal of the adaptive filter.3) Constructed the mathematical model between the self-dithering interference of the non-contact life-parameter detection system... |
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