Traditional methods of non-contact human respiratory rate measurement usually require complex devices or algorithms. Aiming at this problem, a non-contact respiratory rate measurement method based on only the RGB video information was proposed in this paper. The method consisted of four steps. Firstly, spatial filtering was applied to each frame of the input video. Secondly, a gray compensation algorithm was used to compensate for the gray level change caused by the environmental light. Thirdly, the gray levels of each pixel over time were filtered separately by a low-pass filter. Finally, the region of interest was determined based on the filtering results, and the respiration rate of the human is measured. The physical measurement experiments were designed, and the measurement accuracy was compared with that of the biological radar. The error of the proposed method was between - 5.5% and 3% in different detection directions. The results show that the non-contact respiration rate measurement method can effectively measure the human respiration rate.
Algorithms ; Humans ; Radar ; Respiration ; Respiratory Rate

Non-contact vital sign detection technique provides an effective usage in health monitoring applications. A vital sign detector was designed based on microwave bio-radar technique. Using Doppler principle, continuous wave bioradar was designed for tiny body movement detection, short-time Fourier transform and interpolation algorithm were adopted for heart and respiration rate extraction, embedded system was used for system integration, real-time signal processing software was designed on it. Experiments were done by using simulation device and human body for research and performance evaluation. The result shows that the proposed prototype can be used for single target vital signs detection at the distance of 90 cm, and the heart rate result shows a 96% recognition rate.
Equipment Design ; Humans ; Physical Examination ; instrumentation ; methods ; Radar ; Vital Signs

Humans ; Polysomnography ; Radar ; Sleep Apnea, Obstructive ; Syndrome ; Technology

Humans ; Male ; Microwaves ; adverse effects ; Occupational Exposure ; Radar ; Reproductive Health ; Ships

To develop a filtering algorithm which could trace the spectral peaks of the interference and which was used to extract the breath signal with the same band interference in radar non-contact life-detecting system, second filtering algorithm was studied. Through first filtering,the probable interfering spectral peaks (ISP) could be detected by Yule-Walker spectrum estimating and could be located by calculating the coefficients of normalized cross-correlation function according to standard breath signal. Thus the breath signal could be extracted through a second filtering. By using the second filtering algorithm (SFA), the same band interfering spectral peaks with breath signal could be recognized and inhibited. So we conclude that the same band mono-ISP could be inhibited by using SFA and breath signals could be effectively extracted.
Adult ; Algorithms ; Artifacts ; Humans ; Male ; Monitoring, Physiologic ; instrumentation ; methods ; Radar ; instrumentation ; Signal Processing, Computer-Assisted

Adolescent ; Adult ; Asthenopia ; prevention & control ; Humans ; Male ; Military Personnel ; Radar ; Young Adult

Life monitoring technology as the basis of health evaluation, in recent years, its related technology research also has new development, in which cardiopulmonary parameters are the core physiological indicators to measure the basic state of vital signs, the analysis of its monitoring technology is particularly important. In this study, the main means of life monitoring are analyzed, and the monitoring technology of cardiopulmonary parameters is the main focus. What is more, the research status and development of contact and non-contact cardiopulmonary monitoring technology at home and abroad were also considered. Lastly, this study will be combined with the radar wave vital signs monitoring technology, which has been achieved good results in the field of cardiopulmonary monitoring, in order to provide a reference for the long-term development of life monitoring field and the technology integration of intelligent pension, intelligent automobile and other related industries.
Algorithms ; Heart Rate ; Monitoring, Physiologic ; Radar ; Respiratory Rate ; Technology ; Vital Signs

OBJECTIVE: Non-contact continuous blood pressure monitoring is significant in vital sign monitoring. Frequency modulated continuous wave (FMCW) radar is suitable for non-contact wave signal extraction. A heartbeat-guided blood pressure monitoring algorithm using FMCW radar is proposed. METHODS: The target heart rate is detected and pulse wave signal is extracted based on FMCW reflected signals. The variational mode decomposition (VMD) is introduced to alleviate the interferences of human breath and slight body movements. The pulse wave signal is extracted based on target heart rate. Blood pressure related features of pure pulse waveform are extracted to obtain blood pressure based on its estimation model. RESULTS: Experiments are conducted indoor among 15 participants sitting in a nature state. The average accuracy of diastolic blood pressure (DBP) is 94.3% and that of systolic blood pressure is 94.4%. CONCLUSIONS The experimental results demonstrate the robustness and effectiveness of the proposed algorithm, which makes it possible to further achieve long-term real-time non-contact blood pressure monitoring.
Algorithms ; Blood Pressure ; Blood Pressure Determination ; Heart Rate ; Humans ; Radar ; Signal Processing, Computer-Assisted ; Vital Signs

To determine whether a living object is human being or animal by detecting the respiration signal using the life-detector based on radar to penetrate the building or debris. To fully utilize the nonstationary character of the respiration signal, short time Fourier transform (STFT) is employed to get the signal's time-frequency representation. Singular value decomposition (SVD) is then used in the spectrogram to extract feature vector for pattern identification. Human beings and animals can be identified from the respiration sensed by the life-detector based on radar. Experimental results show that the method based on STFT and SVD is stable and efficient to differ from the human being and animal.
Animals ; Dogs ; Equipment Design ; Fourier Analysis ; Humans ; Monitoring, Physiologic ; instrumentation ; Pattern Recognition, Automated ; Radar ; Respiration ; Signal Processing, Computer-Assisted ; Species Specificity ; Swine

OBJECTIVETo evaluate the effect of Long-term exposure to low intensity microwave radiation on male reproductivity.

METHODSA total of 289 married male radar operators were included in the radar group and 148 married men unexposed to microwave radiation were enrolled as controls. Questionnaires were used and the intensity of microwave radiation in different working areas was detected.

RESULTSThe rate of sexual dysfunction was 43.6% in the radar group and 24.4% in the control group (P < 0.01). The natural pregnancy rate was 53.6% within 1 year of marriage and 46.4% after 1 year of marriage in the radar group, as compared with 81.1% and 18.9% in the control group (P < 0.01).

CONCLUSIONLong-term exposure to low intensity microwave radiation evidently increased the sexual dysfunction rate and decreased natural pregnancy rate in men.

Dose-Response Relationship, Radiation ; Erectile Dysfunction ; epidemiology ; Female ; Fertility ; radiation effects ; Humans ; Male ; Microwaves ; adverse effects ; Military Personnel ; Occupational Exposure ; Pregnancy ; Pregnancy Outcome ; Radar ; Radiation Dosage ; Surveys and Questionnaires