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TDL based Digital Equalization Method for Frequency Flatness of Ultra-Wideband mm Wave Channel Emulator

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TDL based Digital Equalization Method for Frequency Flatness...

Antennas and Propagation & USNC/URSI National Radio Science Meeting

作者： Haobo Zhang Chen Chen Dan Fei Hao Zhou Zhuangfei Gui Bo Ai School of Electronic and Information Engineering Beijing Jiaotong University Beijing China Frontiers Science Center for Smart High-speed Railway System Beijing Jiaotong University Beijing China State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing China

ISBN: (数字)9798350369908

ISBN: (纸本)9798350369915

To avoid the deterioration of in-band flatness caused by radio frequency front-ends such as frequency converters in ultra-wideband millimeter-wave channel emulation systems, this paper proposes a digital equalization method that combines filter coefficients with channel time-varying impulse responses. The channel emulation and flatness filter compensation functions are simultaneously realized through the tapped delay line model without the need to add additional high-order filters, which greatly reduces the consumption of hardware resources and simplifies the structure of the baseband system.

关键词： Time-frequency analysis Filtering Millimeter wave technology Emulation Millimeter wave propagation Frequency conversion Hardware

Performance Evaluation of 5G-R Physical Layer Using Hardware-in-the-Loop Simulation Platform

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Performance Evaluation of 5G-R Physical Layer Using Hardware...

Antennas and Propagation & USNC/URSI National Radio Science Meeting

作者： Feng Yuan Dan Fei Peng Zheng Chen Chen Weirong Liu Nan Wang Bo Ai School of Electronic and Information Engineering Beijing Jiaotong University Beijing China State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing China Frontiers Science Center for Smart High-speed Railway System Beijing Jiaotong University Beijing China

ISBN: (数字)9798350369908

ISBN: (纸本)9798350369915

5G network for railway (5G-R) emerges as a promising train-ground communication solution, concurrently facing ubiquitous connectivity and reliable transmission design challenges. This paper focuses on the impact of different channel models and Doppler effects on the physical layer transmission performance of the 5G-R communication system. Based on the 5G-R channel hardware-in-the-loop simulation platform, we measured and compared the performance of the 5G-R system in terms of bit error rate (BER) and error vector magnitude (EVM) across different scenarios. The measurement results reveal that non-line-of-sight propagation and Doppler effects during high-speed movement contribute to the deterioration of the system's BER and EVM. Nevertheless, enhancing the signal-to-noise ratio can mitigate the impact of these factors to some extent.

关键词： Time-frequency analysis Communication systems Hardware-in-the-loop simulation Bit error rate Physical layer Reliability engineering Vectors

Sub-Preferential Rotational Wave Beaming in Structurally Rhombus Re-Entrant Honeycombs

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SSRN 2023年

作者： Zhu, Zhiwei Deng, Zichen State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang050043 China MIIT Key Laboratory of Dynamics and Control of Complex Systems Northwestern Polytechnical University Xi'An710072 China

Rotational waves frequently manifest in micro-structured materials and are often coupled with classical shear or longitudinal wave modes. In this study, a distinctive isolated optical branch, exhibiting very high polarization index related to joint rotation motion, is found in dispersion diagram of elastic wave propagation in structurally rhombus re-entrant honeycomb (SSRH). Through an analysis of group velocity, we further explore the wave beaming of the rotational wave propagation within the SRRH, and intriguingly, observe the emergence of sub-preferential wave beaming occurring along the short diagonal directions. This dynamic anisotropic phenomenon stems from the intricate interplay between wave frequency and structural topology. To elucidate the underlying dynamic anisotropy of rotational waves, we propose a simple rigid-spring model and derive an anisotropic coefficient that precisely captures the intricate frequency-structure coupling behavior. The obtained anisotropic coefficient unveils the formation of sub-preferential directions of the rotational wave within the SRRH. Our findings transcend the elucidation of dynamic anisotropy in lattice materials, extending to practical implications encompassing the manipulation of elastic wave propagation and the design of waveguides. © 2023, The Authors. All rights reserved.

关键词： Anisotropy

Factors Influencing Driver's Expected Psychological Vulnerability When Sharing the Road with Driverless Vehicles

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SSRN 2022年

作者： Wang, Yunze Zhao, Xuhan Zhang, Chunbo State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang050043 China Key Laboratory of Traffic Safety and Control of Hebei Province Shijiazhuang050043 China School of Traffic and Transportation Shijiazhuang Tiedao University Shijiazhuang050043 China

Few studies have examined the psychological experience of drivers of manned vehicles sharing the road with driverless vehicles. To judge whether drivers think they are in a vulnerable state and find out what makes drivers feel they will be in a state we called "expected psychological vulnerability", this paper conducted a questionnaire to collect information about the attitude, perceived usefulness, trust, perceived risk, and demographic information of drivers in a hypothetical situation involving driving on the same road as driverless vehicles. Our goal was to identify areas where the drivers felt that they would be in a "vulnerable psychological state", i.e., that they would be more vulnerable to making poor psychological judgments. The survey results indicated that 43.7 % of the respondents believed that they would be in a vulnerable state in mixed traffic competition, 30.2 % of the respondents did not know whether they would be in a vulnerable state. Further, women, people with a higher education, people with a more aggressive driving personality, older people, and those with more driving experience were more inclined to think that they would not be in a vulnerable state. Attitude, trust, and perceived usefulness all had positive impacts on judgments regarding psychological vulnerability, and perceived risk had a negative impact. Therefore, the early promotion of driverless technology should give priority to people with a higher education, more driving experience, older age, and more aggressive driving personality, and focus on attitudes towards this technology, including perceived usefulness, trust, and perceived risk. © 2022, The Authors. All rights reserved.

关键词： Vehicles

Integrated Capacity Analysis Model and Optimization Based on Conflict Resolution for High-Speed Railway

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Integrated Capacity Analysis Model and Optimization Based on...

Chinese Automation Congress (CAC)

作者： Yuan Wei Lin Ma Jiateng Yin National Engineering Research Center of Rail Transportation Operation and Control System Beijing Jiaotong University Beijing China State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing China

With the increased demand of passengers, the capacity analysis of high-speed railways has attracted much attention for serving more passengers with limited line resources. Existing methods mainly focused on the capacity analysis of rail sections or stations, separately. Our study first addressed the integrated capacity analysis of high-speed railways. We established an integrated capacity analysis model by combining the signal control of track sections, the overtaking of trains and the capacity of rail stations. Then this paper proposed a conflict resolution strategy based on multi-objective optimization. A real-world case study on the Beijing-Shanghai high-speed railway demonstrated that our approach can better model the influencing factors in high-speed railways and can further improve the line capacity compared with existing approaches.

关键词： Rails Analytical models Automation Rail transportation Optimization Signal resolution

Modeling and Simulation for Microscopic traffic Flow Based on Comprehensive Information of The Preceding And the Following Vehicles

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SSRN 2022年

作者： Wang, Yunze Wang, Yawen Zhang, Chunbo State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang05043 China Key Laboratory of Traffic Safety and Control of Hebei Province Shijiazhuang050043 China School of Traffic and Transportation Shijiazhuang Tiedao University Shijiazhuang050043 China

A new car-following model is proposed in this study, and it considers the comprehensive information of the preceding and the following vehicles (i.e., the CIPF model) including the headway, speed difference, and acceleration. This model can be considered as a further extension of the existing forward-backward velocity difference (FBVD) model. Based on the linear stability analysis of the CIPF model, the judgment basis of the traffic flow stability is obtained. Compared with the optimal velocity (OV) model, the full velocity difference (FVD) model, and the FBVD model, the CIPF model has the largest stable region and the smallest unstable region. Using the reductive perturbation method, the nonlinear analysis of the CIPF model is performed, and the modified Korteweg-de Vries (mKdv) equation, which is used to describe the traffic flow characteristics of the system near the critical point, is obtained. Finally, the numerical simulation results show that the CIPF model can respond to the state of traffic flow better and faster than the FBVD model in vehicle start and stop simulation, and can better alleviate traffic congestion and improve the traffic flow stability in the simulation of circular road. The kink-antikink wave described by mKdV equation is simulated in the unstable region after the pe © 2022, The Authors. All rights reserved.

关键词： Nonlinear analysis

Modeling and Simulation for Microscopic traffic Flow Based on Comprehensive Information of The Preceding And the Following Vehicles

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SSRN 2022年

关键词： Nonlinear analysis

Passenger Route and Departure Time Guidance under Disruptions in Oversaturated Urban Rail Transit Networks

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arXiv

arXiv 2024年

作者： Zhuo, Siyu Zhu, Xiaoning Shang, Pan Liu, Zhengke School of Traffic and Transportation Key Laboratory of Transport Industry of Comprehensive Transportation Theory Ministry of Transport Beijing Jiaotong University Beijing100044 China School of Transportation Science and Engineering Beijing Key Laboratory for Cooperative Vehicle Infrastructure System and Safety Control Beihang University Beijing100191 China

The urban rail transit (URT) system attracts many commuters with its punctuality and convenience. However, it is vulnerable to disruptions caused by factors like extreme weather and temporary equipment failures, which greatly impact passengers' journeys and diminish the system's service quality. In this study, we propose targeted travel guidance for passengers at different space-time locations by devising passenger rescheduling strategies during disruptions. This guidance not only offers insights into route changes but also provides practical recommendations for delaying departure times when required. We present a novel three-feature four-group passenger classification principle, integrating temporal, spatial, and spatiotemporal features to classify passengers in disrupted URT networks. This approach results in the creation of four distinct solution spaces based on passenger groups. A mixed integer programming model is built based on individual level considering the First-in-First-out (FIFO) rule in oversaturated networks. Additionally, we present a two-stage solution approach for handling the complex issues in large-scale networks. Experimental results from both small-scale artificial networks and the real-world Beijing URT network validate the efficacy of our proposed passenger rescheduling strategies in mitigating disruptions. Specifically, when compared to scenarios with no travel guidance during disruptions, our strategies achieve a substantial reduction in total passenger travel time by 29.7% and 50.9% respectively, underscoring the effectiveness in managing unexpected disruptions. Copyright © 2024, The Authors. All rights reserved.

关键词： Travel time

Channel Measurement and Analysis for Human Exhalation and Inhalation in Living Room Scenario

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Channel Measurement and Analysis for Human Exhalation and In...

IEEE Conference on Vehicular Technology (VTC)

作者： Ran Pan Danping He Ke Guan Xiaodong Sun Dajie Jiang Fei Qin State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing China Beijing Engineering Research Center of High-Peed Railway System Beijing China Frontiers Science Center for Smart High-Speed Railway System Beijing China VIVO Mobile Communication Co.Ltd. Beijing China

The smart home integrates home-related facilities, which can greatly facilitate people’s life. To support applications such as breath detection and health monitoring for the smart home, it is significant to understand the effect of the human body on the characteristics of the wireless channel. In this paper, the channel characteristics for human exhalation and inhalation at 6.5 GHz are measured and analyzed. Based on the measurement results in the living room scenario, the ray tracing (RT) simulator is calibrated and used to analyze the continuous process of exhalation and inhalation. According to the measurement and simulation results, the effect of human exhalation and inhalation processes on the power and phase of the received signal is studied. The analysis of this paper could be useful in guiding the deployment of smart home devices for human body monitoring. The calibrated electromagnetic (EM) parameters of typical indoor materials will support RT-based channel simulation and modeling in indoor scenarios.

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