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International Symposium on Antennas, Propagation and EM Theory (ISAPE)

作者： Haichao Zhong Gang Li Bo Tian Yongdiao Wen Wei Li Tie Li Science and Technology on Electromechanical Dynamic Control Laboratory Xi'an Institute of Electromechanical Information Technology Xi'an China

ISBN: (数字)9798350353129

ISBN: (纸本)9798350353136

To address the issue of multiple scattering in the propagation of laser fuzes in low-visibility dusty environments, an experiment was conducted to measure the transmittance of laser in such conditions. The corresponding attenuation coefficient was derived based on the Beer-Lambert law. The results indicate that in low-visibility conditions, laser energy attenuates more severely in a dusty environment, with the attenuation coefficient decreasing exponentially as visibility decreases. For instance, at a visibility of 50m, the attenuation coefficient is 192dB/km, and at a visibility of 100m, it is 85dB/km. The experimental results were compared with independent scattering Mie theory calculations and Monte Carlo simulations that consider multiple scattering effects. The findings show significant discrepancies between the experimentally measured attenuation coefficients and Mie theory predictions under low-visibility conditions, whereas the differences with Monte Carlo simulation results, which account for multiple scattering and dust particle shape factors, are smaller. However, the Monte Carlo results are still lower than the experimental measurements in low-visibility conditions. The study concludes that when dust visibility is below approximately 200m, laser transmission simulations must consider multiple scattering and other influencing factors.

关键词： Laser theory Monte Carlo methods Atmospheric measurements Shape Shape measurement Scattering Measurement by laser beam Attenuation measurement Attenuation Particle measurements

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The circuit-level simulation of continuous Wave Doppler Fuze detector based on ADS

The circuit-level simulation of continuous Wave Doppler Fuze...

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International Symposium on Antennas, Propagation and EM Theory (ISAPE)

作者： Xiaoyu Gou Hong Su Tie Li Liang Li Science and Technology on Electromechanical Dynamic Control Laboratory Xi'an China NO.2 Satellite R&D Center Science and Technology on Electromechanical Dynamic Control Laboratory Xi'an China

ISBN: (纸本)9781467317993

Simulation of fuze detector using conventional simulation softwares requires tremendous complicated theoretical calculations. It also can't analyze the impact caused by the nonlinear of the analog devices. A circuit-level simulation method is proposed in this paper to solve this problem, based on the implementation of continuous wave Doppler fuze detector on ADS simulation platform. Continuous Wave Doppler Fuze detector model is built on the ADS platform by using components and Microstrip Line as the same as real circuit and optimizing the analog components parameters by impedance matching. This model launches a Continuous wave signal which has the frequency between 3.36GHz and 3.5GHz, and generates an IF signal of a magnitude between 150mv to 200mv. The results show that this scheme is reasonable and feasible.

关键词： Integrated circuit modeling Detectors Doppler effect Mixers Analytical models Local oscillators

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Near-field Echo Signal Model of Ground Background Based on Scattering Distribution Function

Near-field Echo Signal Model of Ground Background Based on S...

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International Symposium on Antennas, Propagation and EM Theory (ISAPE)

作者： Bo Tian Tie Li Wenhui Hu Sicheng Gao Science and Technology on Electromechanical Dynamic Control Laboratory Xi'anShaanxiChina710061

ISBN: (纸本)9781665418133

Aiming at the problem that the traditional millimeter wave proximity detector model using backscattering coefficients has a large height setting error when the background echo signal quality is poor and the signal-noise ratio is insufficient, a near-field millimeter wave echo signal model based on scattering distribution function for complex feature background is proposed. The model is optimized as an upper half-space scattering distribution function based on the characteristics of feature types to study the near-field scattering functions of soil, vegetation and other backgrounds, and the scattering signals of each microscattering unit in the irradiated area of the detector beam at different moments are calculated in real time by combining with the missile target encounter model, and the echoes received at the detector are obtained in real time after integration. The simulation results show that compared with the traditional method, the model can meet the requirements of detection simulation with higher accuracy of background echo calculation under the condition of lower signal-noise ratio.

关键词： Simulation Millimeter wave technology Scattering Detectors Vegetation Soil Feature extraction

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An Overall Weighted Fusion Algorithm Based on dynamic Optimal Estimation

An Overall Weighted Fusion Algorithm Based on Dynamic Optima...

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control, Electronics and Computer technology (ICCECT), IEEE International Conference on

作者： Zehu Wang Guanglin He Yukuan Liu Science and Technology on Electromechanical Dynamic Control Laboratory Beijing Institute of Technology Beijing China

Based on the background of cooperative detection of target by multiple UAVs, this paper proposes an efficient multi-sensor data fusion algorithm, which is called the overall weighted fusion algorithm based on dynamic optimal estimation (abbreviated as DOE-OWFA) Based on the weighted fusion by the least squares method, the algorithm makes full use of the state estimation property of Kalman Alter for data processing and state estimation. In order to evaluate the performance of the algorithm, we conducted simulation tests with the help of MATLAB. The simulation results show that the algorithm proposed in this paper has higher fusion accuracy and better robustness compared with the same type of algorithms.

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A Design on Silicon-Based Millimeter-Wave Low Noise Amplifier Circuits

A Design on Silicon-Based Millimeter-Wave Low Noise Amplifie...

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IEEE International Conference on Electronic Information and Communication technology (ICEICT)

作者： Zikang Xing Qiuyan Liang Rui Xu Science and Technology on Electromechanical Dynamic Control Laboratory China Xi’an Institute of Electromechanical Information Technology Xi’an China

ISBN: (数字)9798350384437

ISBN: (纸本)9798350384444

This paper investigates the technology of silicon-based millimeter-wave low noise amplifiers (LNA). The LNA consist of two stages of amplifiers connected in cascade. The first stage circuit achieves low noise performance by utilizing minimum noise input matching. The second stage achieves high gain performance by utilizing high gain output matching.. The LNA in this paper achieves a gain S21 of 16 dB at a center frequency of 36 GHz with a noise figure (NF) as small as 5 dB.

关键词： Low-noise amplifiers Noise figure Millimeter wave circuits Impedance matching Noise CMOS technology Silicon

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Feature Extraction and Recognition of Typical Targets by Linear Array LiDAR

Feature Extraction and Recognition of Typical Targets by Lin...

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Intelligent Computing and Human-Computer Interaction (ICHCI), International Conference on

作者： Jian Huo Xu Yang Science and Technology on Electromechanical Dynamic Control Laboratory Beijing Institute of Technology Beijing China

ISBN: (纸本)9781665407656

Aiming at solving the problem that the precision of existing algorithms for sparse point cloud image is unsatisfactory, a target recognition algorithm based on the combination of target shape characteristics and LiDAR echo intensity is proposed. By analyzing and processing the linear array scanning data of the target, remove the ground point cloud by using the point cloud elevation information histogram and the adaptive threshold method of the number of point clouds. On this basis, the mathematical morphology algorithm is used to filter the typical nontarget objects. Finally, the algorithm combining the target shape characteristics and echo intensity is used to realize the accurate recognition of the target. The results show that the algorithm is efficient and easy to implement, and has a good recognition effect on sparse point cloud targets.

关键词： Point cloud compression Human computer interaction Histograms Laser radar Target recognition Shape Morphology

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Mercury flows in large-scale gold production and implications for Hg pollution control

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Journal of Environmental sciences 2018年第6期30卷 91-99页

作者： Qingru Wu Shuxiao Wang Mei Yang Haitao Su Guoliang Li Yi Tang Jiming Hao State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Tsinghua University Beijing 100084 China State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Beijing 100084 China College of Electromechanical Engineering Qingdao University of Science and Technology Qingdao 266061 China

Large-scale gold production（LSGP） is one of the five convention-related atmospheric mercury（Hg） emission sources in the Minamata Convention on Mercury. However, field experiments on Hg flows of the whole process of LSGP are limited. To identify the atmospheric Hg emission points and understand Hg emission characteristics of LSGP, Hg flows in two gold smelters were studied. Overall atmospheric Hg emissions accounted for 10%–17% of total Hg outputs and the Hg emission factors for all processes were 7.6–9.6 kg/ton. There were three dominant atmospheric Hg emission points in the studied gold smelters, including the exhaust gas of the roasting process, exhaust gas from the environmental fog collection stack and exhaust gas from the converter of the refining process. Atmospheric Hg emissions from the roasting process only accounted for 16%–29% of total emissions and the rest were emitted from the refining process. The overall Hg speciation profile（gaseous elemental Hg/gaseous oxidized Hg/particulate-bound Hg） for LSGP was 34.1/57.1/8.8. The dominant Hg output byproducts included waste acid, sulfuric acid and cyanide leaching residue. Total Hg outputs from these three byproducts were 80% in smelter A and 84% in smelter B. Our study indicated that previous atmospheric Hg emissions from large-scale gold production might have been *** emission control in LSGP is not especially urgent in China compared to other significant emission sources（e.g., cement plants）. Instead, LSGP is a potential Hg release source due to the high Hg output proportions to acid and sludge.

关键词： Large-scale gold production Mercury Flow analysis Emission characteristics

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Analysis of the Response Characteristics of Ultra-Wideband Radio Fuze to Interference Signals 4

Analysis of the Response Characteristics of Ultra-Wideband R...

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4th International Conference on Defence technology, ICDT 2024

作者： Hao, Shijun Xie, Jialiang Liang, Yanbin Wu, Kaiwei Yang, Bing Science and Technology on Electromechanical Dynamic Control Laboratory Beijing Institute of Technology Beijing China Air Force Armament Department Shenyang Regional Military Representative Bureau Jilin Regional Military Representative Office Jilin China

The response characteristics of the fuze to the interference signal with reasonable characteristic parameters are similar to the real echo signal, which may lead to the confusion of signal processing and recognition system. To solve this problem, this paper analyzes the influence of characteristic parameters of interference signal on the response characteristics of fuze in detail from two perspectives of time domain and frequency domain, Based on the analysis of receiver principle, the amplitude-frequency response model of sampling integral differential circuit is established, and the response characteristics of interference signal are analyzed from the perspective of frequency domain. Based on the analysis of the time-frequency characteristics of the echo signal of the UWB fuze, a time-frequency function cutting method is proposed to evaluate the anti-jamming performance of the UWB fuze. This methodology was applied to the evaluation of the anti-jamming performance of the UWB fuze to sinusoidal amplitude-modulation interference signal and the results show that the theoretical analysis and simulation results are consistent, and the research provides theoretical guidance for the anti-interference of fuze. © 2024 Institute of Physics Publishing. All rights reserved.

关键词： Jamming

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Dual-Band Substrate Integrated Waveguide Cavity-Backed Antenna Based on LTCC in D-Band

Dual-Band Substrate Integrated Waveguide Cavity-Backed Anten...

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2022 International Applied Computational Electromagnetics Society Symposium, ACES-China 2022

作者： Wang, Dongxu Xu, Kai-Da Xi'an Jiaotong University School of Information and Communications Engineering Xi'an China Science and Technology on Electromechanical Dynamic Control Laboratory Xi'an China Shaanxi Key Laboratory of Artificially-Structured Functional Materials and Devices Xi'an China

ISBN: (纸本)9781665452366

In this paper, a D-band dual-band substrate integrated waveguide (SIW) cavity-backed antenna based on low temperature co-fired ceramic (LTCC) fed by standard Flange of WR-6.5 rectangular waveguide (RWG) has been proposed. The dual-band cavity-backed antenna operates at its two high-order radiation modes through the four radiating slots etched on the top of its surface coupled by an hourglass-shaped inductive window. In addition, the design of SIW-RWG vertical transition is in order to transmit the power from the waveguide to the SIW cavity-backed antenna efficiently. The 10-dB impedance bandwidths of the proposed antenna are over 3% at both radiation frequencies of 146.6 and 167.2 GHz, while the maximum realized gains are 8.73 and 9.29 dBi, respectively. According to the LTCC process, the structure of the antenna is able to be stable and well performed. © 2022 IEEE.

关键词： Substrate integrated waveguides

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Object Detection Based on Digital Twin-Based Road Scenarios

Object Detection Based on Digital Twin-Based Road Scenarios

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control, Electronics and Computer technology (ICCECT), IEEE International Conference on

作者： Zhang Yu Chen Huimin Wang Weihan Science and Technology on Electromechanical Dynamic Control Laboratory Beijing Institute of Technology Beijing China

ISBN: (数字)9798350380958

ISBN: (纸本)9798350380965

With the rapid development of artificial intelligence and digital technology, digital twins are becoming more and more widely used in various fields, and have high application value in industrial production, architectural design and other fields. There are few datasets of extreme scenarios used in traditional object detection and vehicle autonomous driving training, resulting in unsatisfactory results of object detection and autonomous driving technology in complex environments. In this paper, a digital twin model of the road scene is built based on the rules of City Engine and the Unreal Engine 4 platform, which can be used to build a model of complex road scenes and shorten the model construction cycle. Based on the constructed digital twin model, the target detection task is carried out, and it is verified that the target detection and autonomous driving tests can be carried out in the digital twin model. It provides ideas for solving the problem of insufficient testing of autonomous driving and object detection tasks in complex and extreme scenarios.

关键词： Training Roads Urban areas Object detection Digital twins Task analysis Artificial intelligence

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