scholarly journals Portable Micro-Doppler Radar with Quadrature Radar Architecture for Non-Contact Human Breath Detection

Sensors ◽  
2021 ◽  
Vol 21 (17) ◽  
pp. 5807
Author(s):  
Catur Apriono ◽  
Fathul Muin ◽  
Filbert H. Juwono
Keyword(s):  
Respiration Rate ◽  
Doppler Radar ◽  
Detection System ◽  
Experimental System ◽  
Radar System ◽  
Acceptable Error ◽  
Radio Detection ◽  
Human Respiration ◽  
Technology Applications ◽  
Main Component

Recently, rapid advances in radio detection and ranging (radar) technology applications have been implemented in various fields. In particular, micro-Doppler radar has been widely developed to perform certain tasks, such as detection of buried victims in natural disaster, drone system detection, and classification of humans and animals. Further, micro-Doppler radar can also be implemented in medical applications for remote monitoring and examination. This paper proposes a human respiration rate detection system using micro-Doppler radar with quadrature architecture in the industrial, scientific, and medical (ISM) frequency of 5.8 GHz. We use a mathematical model of human breathing to further explore any insights into signal processes in the radar. The experimental system is designed using the USRP B200 mini-module as the main component of the radar and the Vivaldi antennas working at 5.8 GHz. The radar system is integrated directly with the GNU Radio Companion software as the processing part. Using a frequency of 5.8 GHz and USRP output power of 0.33 mW, our proposed method was able to detect the respiration rate at a distance of 2 m or less with acceptable error. In addition, the radar system could differentiate different frequency rates for different targets, demonstrating that it is highly sensitive. We also emphasize that the designed radar system can be used as a portable device which offers flexibility to be used anytime and anywhere.

Real-time Rockfall Detection System with Automatic Road Closure and Reopening using Doppler Radar Technology at the Ruinon Landslide, Italy

2021 ◽  
Author(s):  
Susanne Wahlen ◽  
Severin Stähly ◽  
Lino Schmid ◽  
Lorenz Meier ◽  
Tommaso Carlà ◽  
...  
Keyword(s):  
Real Time ◽  
Doppler Radar ◽  
Detection System ◽  
Radar System ◽  
Slope Instability ◽  
Alarm System ◽  
Protection Measures ◽  
Traffic Lights ◽  
The Road ◽  
Road Closure

<p>Transportation corridors in mountain regions are often situated at the bottom of narrow valleys. Changing slope stability conditions can put these routes at critical risk. Slope stabilization works (e.g., rock scaling, blasting) or structural protection measures (e.g., rock sheds, reinforced embankments, tunnels) are not always feasible or may not be cost-effective due to low average daily traffic or the expected event size. Route SP29 is the main connection road to Santa Catarina, a popular tourist resort in the Frodolfo River Valley, Lombardy, Italy. The Ruinon landslide is a major slope instability involving approximately 30 million m<sup>3</sup> of rock and debris and causes repeated rockfalls that can reach as far as the road. </p><p>We present a Doppler radar system for real-time rockfall detection and immediate road closure in case of an event. The rockfall radar permanently monitors the landslide area from the opposite side of the slope with a range of more than 1 km to the upper scarp. Radar technology works reliably regardless of visibility, i.e. in rain, fog or snowfall as well as at night. After an initial calibration period in summer 2020, we activated automatic road closure and reopening in case of a rockfall event; upon detection of rockfall in a defined region of interest, the radar system automatically switches the traffic lights to red. If the rock fall event reaches a defined zone near the road or the road itself, it remains closed and requires manual reset after site inspection with webcams at the radar site and the traffic lights. If the rockfall event remains above the road, then the radar system automatically releases the road again after 90 seconds. Automatic notifications about the status are sent to authorized user via email and SMS. In addition to the deployment of the alarm system using Doppler radar, the embankment along the endangered road section was reinforced and raised. These combined measures of protection structures and alarm system aim at maximising the opening hours of the street while providing the highest possible level of protection. Between July (installation) and December 2020, 60 rockfall events caused a road closure, with the road being automatically reopened by the system in approximately 85% of cases.</p>

scholarly journals A Novel Wireless-Netted UWB Life-Detection Radar System for Quasi-Static Person Sensing

2021 ◽  
Vol 11 (1) ◽  
pp. 424
Author(s):  
Kun Yan ◽  
Shiyou Wu ◽  
Shengbo Ye ◽  
Guangyou Fang
Keyword(s):  
Detection System ◽  
Signal To Noise Ratio ◽  
Observation Point ◽  
Radar System ◽  
Brick Wall ◽  
Efficient Detection ◽  
Human Respiration ◽  
Radar Applications ◽  
Life Detection ◽  
Point Detection

In actual life-detection radar applications, a quasi-static person with weak respiration is difficult to find when relying on the echoes from a single fixed observation point. To effectively sense the weak respiration of a quasi-static person in complex through-wall and through-floor conditions, this paper proposes a novel multi-observation point detection system composed of multiple Golay complementary coded radars in which communication and synchronization are carried out wirelessly. The collaboration structure and Golay complementary coded transmitter improve the signal to noise ratio (SNR). Proof-of-principle experiments are carried out with our designed radar prototype and prove that the radar system can detect a respiring target 21 m behind a brick wall or a respiring target behind two levels of reinforced concrete floors, validating the effectiveness of a multi-observation point working mode for the efficient detection of weak human respiration.

Sign in / Sign up

Export Citation Format

Share Document