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Locating the position of objects in non-line-of-sight based on time delay estimation

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Chinese Physics B 2016年第8期25卷 163-169页

作者：王雪峰王元庆苏金善杨兴雨 School of Electronic Science and Engineering Nanjing University School of Electronic Information Engineering Yili Normal University

non-line-of-sight imaging detection is to detect hidden objects by indirect light and intermediary surface（diffuser）.It has very important significance in indirect access to an object or dangerous object detection, such as medical treatment and rescue. An approach to locating the positions of hidden objects is proposed based on time delay estimation. The time delays between the received signals and the source signal can be obtained by correlation analysis, and then the positions of hidden objects will be located. Compared with earlier systems and methods, the proposed approach has some modifications and provides significant improvements, such as quick data acquisition, simple system structure and low cost, and can locate the positions of hidden objects as well： this technology lays a good foundation for developing a practical system that can be used in real applications.

关键词： non-line-of-sight time delay estimation cross-correlation hidden object location

A non-line-of-sight Error Mitigation Method in Wireless Location System

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A Non-Line-of-Sight Error Mitigation Method in Wireless Loca...

Aspiration of coagulated hematoma in the third and fourth ventricles via paracele anterior horn puncture

2009 2nd IEEE International Conference on Computer Science and Information Technology（ICCSIT 2009）

作者： He Yuanhua and Li Hongsheng School of Automation Wuhan University of Technology WHUT Wuhan China

A key obstacle to high accuracy location is the none line of sight （NLOS） transmission of signal in wireless localization.It adds positive error to distance measurements.An effective location algorithm based on nonlinear constraint optimization is proposed to mitigate NLOS errors.The proposed method forms distance error optimization constraint using the geometric relationship between the base stations and mobile station.It improves the location accuracy by calibrating the distance measurements and modifying the objective function.Simulation results show that this new method can efficiently reduce the effect of the NLOS error,and is robust to different NLOS error.

关键词： wireless location non-line-of-sight constrained optimization

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Chinese Journal of Traumatology 2016年第1期19卷 28-30页

作者： Zhi-Qiang Tao Sheng-Hong Ding Department of Neurosurgery Yiwu Central Hospital Wenzhou Medical College Yiwu 32200 Zhejiang Province China

Intraventricular hemorrhage (IVH) is a neurological urgency with a high mortality and unfavorable prognosis. Fast removal of intraventricular blood should be considered as a priority. The current treatments of IVH mainly focus on external ventricular drain and endoscopic aspiration, but neither way can remove the blood in the fourth ventricle easily and relieve the compression of brainstem. Here we report a unique procedure to solve this problem. A 41-year-old male patient who had suffered sudden attack of headache and disturbance of consciousness for 2 h was diagnosed as having high density lesion in the whole ventricular system by computed tomographic (CT) imaging. An emergent bilateral ventriculopuncture and intraventricular hematoma removal under non-line-of-sight was performed immediately; the catheter was extended to the fourth ventricle to maximally remove the hematoma. Postoperative CT scan demonstrated total removal of IVH and no sign of extra brain damage.

关键词： Intraventricular hemorrhage Ventriculopuncture Aspiration non-line-of-sight

Robust location algorithm for NLOS environments

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Journal of Systems Engineering and Electronics 2008年第4期19卷 812-818页

作者： Huang Jiyan Wan Qun Dept of Electronic Engineering Univ. of Electronic Science and Technology of China Chengdu 610054 P. R. China

One of the main problems facing accurate location in wireless communication systems is non-line-of- sight （NLOS） propagation. Traditional location algorithms are based on classical techniques under minimizing a least-squares objective function and it loses optimality when the NLOS error distribution deviates from Gaussian distribution. An effective location algorithm based on a robust objective function is proposed to mitigate NLOS errors. The proposed method does not require the prior knowledge of the NLOS error distribution and can give a closed-form solution. A comparison is performed in different NLOS environments between the proposed algorithm and two additional ones （LS method and Chan＇s method with an NLOS correction）. The proposed algorithm clearly outperforms the other two.

关键词： wireless location time-of-arrival non-line-of-sight robust objective function

Ultraviolet communication technique and its application

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Journal of Semiconductors 2021年第8期42卷 32-44页

作者： Liang Guo Yanan Guo Junxi Wang Tongbo Wei Research and Development Center for Semiconductor Lighting Technology Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Beijing Engineering Research Center for the 3rd Generation Semiconductor Materials and Application Beijing 100083China

With recent developments of deep ultraviolet(DUV)light-emitting diodes and solar-blind detectors,UV communication(UVC)shows great potential in replacing traditional wireless communication in more and more scenarios.Based on the atmospheric scattering of UV radiation,UVC has gained considerable attention due to its non-line-of-sight ability,omnidirectional communication links and low background noise.These advantages make UVC an ideal option for covert secure communication,especially for military communication.In this review,we present the history and working principle of UVC with a special focus on its light sources and detectors.Comprehensive comparison and application of its light sources and detectors are provided to the best of our knowledge.We further discuss the future application and outlook of UVC.Hopefully,this review will offer valuable insights into the future development of UVC.

关键词： ultraviolet communication non-line-of-sight optical wireless communication

Structural Design of High-precision Positioning System in Weak Signal Environment Based on UWB and IMU Fusion

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Instrumentation 2023年第2期10卷 30-39页

作者： ZHAO Yang WANG Tianhu LI Wenjie MIAO Qiannian SHEN Yunzhe HUANG Tao School of Electrical Information Engineering Jiangsu University of TechnologyChangzhouJiangsu213001China Technical Development Department of CRRC Nanjing Puzhen Vehicle Co. LtdNanjing 211800China

Aiming at the problem that indoor positioning technology based on wireless ultra-wideband pulse technology is susceptible to non-line-of-sight effects and multipath effects in confined spaces and weak signal environments,a high-precision positioning system based on UWB and IMU in a confined environment is designed.The STM32 chip is used as the main control,and the data information of IMU and UWB is fused by the fusion filtering algorithm.Finally,the real-time information of the positioning is transmitted to the host computer and the cloud.The experimental results show that the positioning accuracy and positioning stability of the system have been improved in the non-line-of-sight case of closed environment.The system has high positioning accuracy in a closed environment,and the components used are consumer-grade,which has strong practicability.

关键词： Ultra-wideband Inertial Sensor Weak Signal Environment non-line-of-sight

The realization of a wide-angle voice transmission non-line-ofsight ultraviolet communication system

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Journal of Semiconductors 2021年第9期42卷 47-52页

作者： Yangyang Deng Yuehui Wang Yiqing Zhang Axin Du Jianguo Liu University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Integrated Optoelectronics Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China School of Materials Science and Opto-Electronic Technology University of Chinese Academy of SciencesBeijing 100049China School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of SciencesBeijing 101408China

A 300 kbps wide-angle non-line-of-sight ultraviolet communication system with voice transmission function is designed here.Based on Poisson distribution theory,we design the symbol detecting method for the receiving discrete photon signals.Using 272 nm LED array as the light source and PMT as the detector,the voice transceiver is integrated into the carriable size of 200×90×65 mm^(3).An outfield test shows the system obtains the BER of 0.88% under 200 m.Under 10°wide-angle deviation of the transmitter,a BER below 1.33% is achieved.

关键词： non-line-of-sight ultraviolet communication solar-blind

NLOS环境下基于信号检测的单次与二次散射路径识别

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信号处理 2020年第5期36卷 733-740页

作者：谢少杰邓平西南交通大学信息编码与传输重点实验室四川成都611700

针对NLOS(non-line-of-sight)传播环境中单次与多次散射路径的识别问题,本文基于单次散射圆环模型建立了一种二次散射圆环模型,对该模型的统计特征进行了分析。同时,基于信号统计检测理论建立了一种单次与二次散射路径检测模型,然后根... 详细信息

针对NLOS(non-line-of-sight)传播环境中单次与多次散射路径的识别问题,本文基于单次散射圆环模型建立了一种二次散射圆环模型,对该模型的统计特征进行了分析。同时,基于信号统计检测理论建立了一种单次与二次散射路径检测模型,然后根据是否已知先验概率两种情况,分别采用广义似然比和奈曼皮尔逊准则来检测识别两种散射路径。仿真结果表明:本文提出的检测识别方法在NLOS环境下能有效识别两种散射路径,相对于LPMD(line of Possible Mobile Device)算法具有更高的识别率以及更小的虚警概率和漏警概率,且时间开销小,具有一定的应用价值。

关键词：二次散射散射模型 non-line-of-sight 信号检测路径识别

Impacts of Transceiver Configuration on Ultraviolet Communication

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Optics and Photonics Journal 2020年第6期10卷 89-94页

作者： Tao Shan Jianshe Ma Tianfeng Wu Zanqiu Shen Ping Su Department of Precision Instrument Tsinghua University Beijing China Tsinghua Shenzhen International Graduate School Tsinghua University Shenzhen China

In the channel estimation for ultraviolet communication, the single scattering power is usually used to approximate the received total power. This approximation error is affected by the transceiver configuration. Here, we employ the proportion of received single scattering power in received total power to indicate the approximation error of the single scattering model in different configurations. This is useful for reducing the approximation error by selecting a more appropriate transceiver configuration.

关键词： Ultraviolet Communication Single Scattering non-line-of-sight