Harmonic Path (HAPA) algorithm for non-contact vital signs monitoring with IR-UWB radar

Vital signs monitoring in physical activity (PA) is of great significance in daily healthcare. Impulse Radio Ultra-WideBand (IR-UWB) radar provides a contactless vital signs detection approach with advantages in range resolution and penetration. Several researches have verified the feasibility of IR-UWB radar monitoring when the target keeps still. However, various body movements are induced by PA, which lead to severe signal distortion and interfere vital signs extraction. To address this challenge, a novel joint chest–abdomen cardiopulmonary signal estimation approach is proposed to detect breath and heartbeat simultaneously using IR-UWB radars. The movements of target chest and abdomen are detected by two IR-UWB radars, respectively. Considering the signal overlapping of vital signs and body motion artifacts, Empirical Wavelet Transform (EWT) is applied on received radar signals to remove clutter and mitigate movement interference. Moreover, improved EWT with frequency segmentation refinement is applied on each radar to decompose vital signals of target chest and abdomen to vital sign-related sub-signals, respectively. After that, based on the thoracoabdominal movement correlation, cross-correlation functions are calculated among chest and abdomen sub-signals to estimate breath and heartbeat. The experiments are conducted under three kinds of PA situations and two general body movements, the results of which indicate the effectiveness and superiority of the proposed approach.

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Vital signs monitoring using an IR-UWB radar based on edge computing

IET International Radar Conference (IET IRC 2020) ◽

10.1049/icp.2021.0806 ◽

2021 ◽

Author(s):

N. Zhu ◽

B. Liu ◽

R. Qi ◽

Z. Chen ◽

S. Xu ◽

...

Keyword(s):

Vital Signs ◽

Edge Computing ◽

Vital Signs Monitoring ◽

Uwb Radar

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Preclinical evaluation of noncontact vital signs monitoring using real-time IR-UWB radar and factors affecting its accuracy

Scientific Reports ◽

10.1038/s41598-021-03069-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Jun-Young Park ◽

Yonggu Lee ◽

Ran Heo ◽

Hyun-Kyung Park ◽

Seok-Hyun Cho ◽

...

Keyword(s):

Real Time ◽

Vital Sign ◽

Vital Signs ◽

Embedded Processors ◽

Sitting Position ◽

Mixed Effect ◽

Factors Affecting ◽

Vital Signs Monitoring ◽

Uwb Radar ◽

The Absolute

AbstractRecently, noncontact vital sign monitors have attracted attention because of issues related to the transmission of contagious diseases. We developed a real-time vital sign monitor using impulse-radio ultrawideband (IR-UWB) radar with embedded processors and software; we then evaluated its accuracy in measuring heart rate (HR) and respiratory rate (RR) and investigated the factors affecting the accuracy of the radar-based measurements. In 50 patients visiting a cardiology clinic, HR and RR were measured using IR-UWB radar simultaneously with electrocardiography and capnometry. All patients underwent HR and RR measurements in 2 postures—supine and sitting—for 2 min each. There was a high agreement between the RR measured using radar and capnometry (concordance correlation coefficient [CCC] 0.925 [0.919–0.926]; upper and lower limits of agreement [LOA], − 2.21 and 3.90 breaths/min). The HR measured using radar was also in close agreement with the value measured using electrocardiography (CCC 0.749 [0.738–0.760]; upper and lower LOA, − 12.78 and 15.04 beats/min). Linear mixed effect models showed that the sitting position and an HR < 70 bpm were associated with an increase in the absolute biases of the HR, whereas the sitting position and an RR < 18 breaths/min were associated with an increase in the absolute biases of the RR. The IR-UWB radar sensor with embedded processors and software can measure the RR and HR in real time with high precision. The sitting position and a low RR or HR were associated with the accuracy of RR and HR measurement, respectively, using IR-UWB radar.

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A robust multi-feature based method for distinguishing between humans and pets to ensure signal source in vital signs monitoring using UWB radar

EURASIP Journal on Advances in Signal Processing ◽

10.1186/s13634-021-00738-2 ◽

2021 ◽

Vol 2021 (1) ◽

Author(s):

Yangyang Ma ◽

Pengfei Wang ◽

Wenzhe Huang ◽

Fugui Qi ◽

Fulai Liang ◽

...

Keyword(s):

Characteristic Curve ◽

Vital Signs ◽

Ultra Wideband ◽

Recursive Feature Elimination ◽

Support Vector ◽

Signal Source ◽

Vital Signs Monitoring ◽

Uwb Radar ◽

Svm Model ◽

Feature Based

AbstractPets have been indispensable members for many families in modern life, especially significant for the elderly and the blind. However, they may cause false alarm when misused as signal source in non-contact monitoring of the vital signs using ultra-wideband (UWB) radar. Distinguishing between humans and pets can help ensure the correct signal source. Nevertheless, existing solutions are few or only utilize a single feature, which can hinder robustness and accuracy because of individual differences. In this study, we proposed a robust multi-feature based method to solve the problem. First, 19 discriminative features were extracted to reflect differences in aspects of energy, frequency, wavelet entropy, and correlation coefficient. Second, the features were ranked by recursive feature elimination algorithm and the top eight were then selected to build an optimal support vector machine (SVM) model. The area under the receiver operating characteristic curve (AUC) of the optimal SVM model reached 0.9620. The false and missing alarms for identifying humans were 0.0962 and 0.0600, respectively. Finally, comparison with the state-of-the-art method that only employed one feature validated the advance and accuracy of the proposed method. The method is envisioned to facilitate the UWB radar applications in non-contact and continuous vital signs monitoring.

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ANALYSIS OF VITAL SIGNS MONITORING USING AN IR-UWB RADAR

Progress In Electromagnetics Research ◽

10.2528/pier09120302 ◽

2010 ◽

Vol 100 ◽

pp. 265-284 ◽

Cited By ~ 203

Author(s):

Antonio Lazaro ◽

David Girbau ◽

Ramon Villarino

Keyword(s):

Vital Signs ◽

Vital Signs Monitoring ◽

Uwb Radar

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Resonator Based Switching Technique between Ultra Wide Band (UWB) and Single/Dual Continuously Tunable-Notch Behaviors in UWB Radar for Wireless Vital Signs Monitoring

Sensors ◽

10.3390/s18103330 ◽

2018 ◽

Vol 18 (10) ◽

pp. 3330 ◽

Cited By ~ 21

Author(s):

MuhibUr Rahman ◽

Mahdi NaghshvarianJahromi ◽

Seyed Sajad Mirjavadi ◽

Abdel Magid Hamouda

Keyword(s):

Monitoring System ◽

Frequency Band ◽

Ground Plane ◽

Vital Signs ◽

Wide Band ◽

Ultra Wide Band ◽

Uwb Antenna ◽

Vital Signs Monitoring ◽

Uwb Radar ◽

Compact Size

This paper presents a novel resonator that can switch and create three important behaviors within the same antenna using miniaturized capacitors. The resonator was integrated into conventional Ultra-Wide Band (UWB) antenna to achieve UWB and Single/Dual continuously tunable-notch behaviors. The Single/Dual notched was continuously tuned to our desired frequency band by changing the value of the capacitors. The antenna designed and fabricated to validate these behaviors had a compact size of 24 × 30.5 mm2, including the ground plane. The radiation patterns were very clean due to the placement of the proposed resonator in the special ground plane. Moreover, the presented novel resonator and switching technique was compared with the recently proposed resonators and their switching techniques. The prototype for the antenna was also developed in order to validate its performance in wireless vital signs monitoring. The presented miniaturized resonator based antenna was utilized for tumor sensing and simulations were provided in this regard. Moreover, the deployment of the proposed resonator based UWB antenna sensor in Pipeline Integrity Monitoring system was also investigated and discussed.

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Method for Distinguishing Humans and Animals in Vital Signs Monitoring Using IR-UWB Radar

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph16224462 ◽

2019 ◽

Vol 16 (22) ◽

pp. 4462 ◽

Cited By ~ 3

Author(s):

Wang ◽

Zhang ◽

Ma ◽

Liang ◽

An ◽

...

Keyword(s):

Home Environment ◽

Vital Signs ◽

Noise Removal ◽

Intrinsic Mode Functions ◽

Sleep Monitoring ◽

Vital Signs Monitoring ◽

Uwb Radar ◽

Mode Decomposition ◽

Human Respiration ◽

Frequency Domains

Radar has been widely applied in many scenarios as a critical remote sensing tool for non-contact vital sign monitoring, particularly for sleep monitoring and heart rate measurement within the home environment. For non-contact monitoring with radar, interference from house pets is an important issue that has been neglected in the past. Many animals have respiratory frequencies similar to those of humans, and they are easily mistaken for human targets in non-contact monitoring, which would trigger a false alarm because of incorrect physiological parameters from the animal. In this study, humans and common pets in families, such as dogs, cats, and rabbits, were detected using an impulse radio ultrawideband (IR-UWB) radar, and the echo signals were analyzed in the time and frequency domains. Subsequently, based on the distinct in-body structure between humans and animals, we propose a parameter, the respiratory and heartbeat energy ratio (RHER), which reflects the contribution rate of breathing and heartbeat in the detected vital signs. Combining this parameter with the energy index, we developed a novel scheme to distinguish between humans and animals. In the developed scheme, after background noise removal and direct-current component suppression, an energy indicator is used to initially identify the target. The signal is then decomposed using a variational mode decomposition algorithm, and the variational intrinsic mode functions that represent human respiration and heartbeat components are obtained and utilized to calculate the RHER parameter. Finally, the RHER index is applied to rapidly distinguish between humans and animals. Our experimental results demonstrate that the proposed approach more effectively distinguishes between humans and animals in terms of monitoring vital signs than the existing methods. Furthermore, its rapidity and need for only minimal calculation resources enable it to meet the needs of real-time monitoring.

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Longitudinal remotely mentored self-performed lung ultrasound surveillance of paucisymptomatic Covid-19 patients at risk of disease progression

The Ultrasound Journal ◽

10.1186/s13089-021-00231-9 ◽

2021 ◽

Vol 13 (1) ◽

Author(s):

Andrew W. Kirkpatrick ◽

Jessica L. McKee ◽

John M. Conly

Keyword(s):

At Risk ◽

Lung Ultrasound ◽

Point Of Care ◽

Human Life ◽

Vital Signs ◽

Home Monitoring ◽

Cost Effective ◽

Care Providers ◽

Vital Signs Monitoring ◽

Ultrasound Probes

AbstractCOVID-19 has impacted human life globally and threatens to overwhelm health-care resources. Infection rates are rapidly rising almost everywhere, and new approaches are required to both prevent transmission, but to also monitor and rescue infected and at-risk patients from severe complications. Point-of-care lung ultrasound has received intense attention as a cost-effective technology that can aid early diagnosis, triage, and longitudinal follow-up of lung health. Detecting pleural abnormalities in previously healthy lungs reveal the beginning of lung inflammation eventually requiring mechanical ventilation with sensitivities superior to chest radiographs or oxygen saturation monitoring. Using a paradigm first developed for space-medicine known as Remotely Telementored Self-Performed Ultrasound (RTSPUS), motivated patients with portable smartphone support ultrasound probes can be guided completely remotely by a remote lung imaging expert to longitudinally follow the health of their own lungs. Ultrasound probes can be couriered or even delivered by drone and can be easily sterilized or dedicated to one or a commonly exposed cohort of individuals. Using medical outreach supported by remote vital signs monitoring and lung ultrasound health surveillance would allow clinicians to follow and virtually lay hands upon many at-risk paucisymptomatic patients. Our initial experiences with such patients are presented, and we believe present a paradigm for an evolution in rich home-monitoring of the many patients expected to become infected and who threaten to overwhelm resources if they must all be assessed in person by at-risk care providers.

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