scholarly journals An Automated Real-Time Localization System in Highway and Tunnel Using UWB DL-TDoA Technology

2020 ◽  
Vol 2020 ◽  
pp. 1-15
Author(s):  
Long Wen ◽  
Jinkun Han ◽  
Liangliang Song ◽  
Qi Zhang ◽  
Kai Li ◽  
...  

There exists an electromagnetic shielding effect on radio signals in a tunnel, which results in no satellite positioning signal in the tunnel scenario. Moreover, because vehicles always drive at a high speed on the highway, the real-time localization system (RTLS) has a bottleneck in a highway scenario. Thus, the navigation and positioning service in tunnel and highway is an important technology difficulty in the construction of a smart transportation system. In this paper, a new technology combined downlink time difference of arrival (DL-TDoA) is proposed to realize precise and automated RTLS in tunnel and highway scenarios. The DL-TDoA inherits ultra-wideband (UWB) technology to measure the time difference of radio signal propagation between the location tag and four different location base stations, to obtain the distance differences between the location tag and four groups of location base stations. The proposed solution achieves a higher positioning efficiency and positioning capacity to achieve dynamic RTLS. The DL-TDoA technology based on UWB has several advantages in precise positioning and navigation, such as positioning accuracy, security, anti-interference, and power consumption. In the final experiments on both static and dynamic tests, DL-TDoA represents high accuracy and the mean errors of 11.96 cm, 37.11 cm, 50.06 cm, and 87.03 cm in the scenarios of static tests and 30 km/h, 60 km/h, and 80 km/h in dynamic tests, respectively, which satisfy the requirements of RTLS.

2018 ◽  
Vol 14 (5) ◽  
pp. 155014771877447 ◽  
Author(s):  
Minhyuk Kim ◽  
Sekchin Chang

This article addresses a novel real-time locating system for localization of high-speed mobile objects in fading environments. The proposed locating system exploits time difference of arrival measurements based on ultra-wideband signals. However, the ultra-wideband signals cause a frequency-selective fading due to their short time duration, which induces severe inter-symbol interference. Moreover, high-speed objects cause fast fading due to large Doppler spread. Therefore, the fading cases considerably reduce the localization performance. The presented locating system relies on a new localization approach in order to overcome the fading issues, which utilizes a modification of extended Kalman filtering. Especially, the suggested locating method works well even in the zero time difference of arrival case, which occurs due to a very deep fading. Experiment results verify that the proposed real-time locating system gives excellent localization performance in severe fading environments. The results also exhibit that the presented locating system is superior to the conventional locating systems in the localization of high-speed mobile objects under fading environments.


1981 ◽  
Vol 103 (3) ◽  
pp. 255-260 ◽  
Author(s):  
W. Johnson ◽  
S. R. Reid ◽  
S. K. Ghosh

Experiments are described in which cylindrical tubes were perforated normally at their central section. Quasi-static tests were performed using mainly square-section punches possessing pointed pyramidal heads of semi-angle 30 deg, the tubes being supported along their support generator. The dynamic tests comprised high-speed penetration of tubes using conically headed cylindrical projectiles. The equipment and experimental procedures are briefly described and results are presented showing typical punch load-penetration curves, the variation of punch load with tube length and that of a nondimensional characteristic punch load (defined later) with length-to-diameter ratio of the tubes. Typical specimens and the sequence of events during the course of a penetration process are also illustrated. The characteristics of petalling and plugging modes of failure together with those effects which are specifically dynamic in character are reported.


2020 ◽  
Vol 15 (8) ◽  
pp. 1176-1182
Author(s):  
Li Zheng‐dong ◽  
Chen Xing‐jie ◽  
Li Xiu‐ling ◽  
Cai Juan ◽  
He Yan ◽  
...  

1998 ◽  
Vol 120 (6) ◽  
pp. 693-696 ◽  
Author(s):  
L. M. Voo ◽  
F. A. Pintar ◽  
N. Yoganandan ◽  
Y. K. Liu

The quasi-static and dynamic bending responses of the human mid-lower cervical spine were determined using cadaver intervertebral joints fixed at the base to a six-axis load cell. Flexion bending moment was applied to the superior end of the specimen using an electrohydraulic piston. Each specimen was tested under three cycles of quasi-static load-unload and one high-speed dynamic load. A total of five specimens were included in this study. The maximum intervertebral rotation ranged from 11.0 to 15.4 deg for quasi-static tests and from 22.9 to 34.4 deg for dynamic tests. The resulting peak moments at the center of the intervertebral joint ranged from 3.8 to 6.9 Nm for quasi-static tests and from 14.0 to 31.8 Nm for dynamic tests. The quasi-static stiffness ranged from 0.80 to 1.35 Nm/deg with a mean of 1.03 Nm/deg (±0.11 Nm/deg). The dynamic stiffness ranged from 1.08 to 2.00 Nm/deg with a mean of 1.50 Nm/deg (±0.17 Nm/deg). The differences between the two stiffnesses were statistically significant (p < 0.01). Exponential functions were derived to describe the quasi-static and dynamic moment-rotation responses. These results provide input data for lumped-parameter models and validation data for finite element models to better investigate the biomechanics of the human cervical spine.


Author(s):  
Nadia Ghariani ◽  
Mohamed Salah Karoui ◽  
Mondher Chaoui ◽  
Mongi Lahiani ◽  
Hamadi Ghariani

1995 ◽  
Author(s):  
Rod Clark ◽  
John Karpinsky ◽  
Gregg Borek ◽  
Eric Johnson
Keyword(s):  

Author(s):  
Kenneth Krieg ◽  
Richard Qi ◽  
Douglas Thomson ◽  
Greg Bridges

Abstract A contact probing system for surface imaging and real-time signal measurement of deep sub-micron integrated circuits is discussed. The probe fits on a standard probe-station and utilizes a conductive atomic force microscope tip to rapidly measure the surface topography and acquire real-time highfrequency signals from features as small as 0.18 micron. The micromachined probe structure minimizes parasitic coupling and the probe achieves a bandwidth greater than 3 GHz, with a capacitive loading of less than 120 fF. High-resolution images of submicron structures and waveforms acquired from high-speed devices are presented.


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