This research investigate the information interaction protocols for Cooperative vehicleinfrastructure systems (CVIS) safety-related services and optimizes them in three aspects. It puts forward a selfadaptive back-off algorithm. algorithm considers retransmission times network busy degree to choose suitable contention window. A mathematical analysis model is developed verify its performance improvement. Finally, different scenario models of Vehicle ad hoc (VANET) are simulated through...

In order to meet the requirements of higher economic operating speed, constructing a vacuum tube environment is an important direction for future development ultra high speed rail transit technology. Due non-stationary nature wireless channels during movement, traditional channel models are no longer suitable train communication systems in scenarios. Existing modeling methods cannot accurately reflect wave propagation characteristics. This article based on GBSM (Geometry Stochastic Model)...

Abstract Presently, Radar Target Simulator (RTS) has become a key instrument in the research and development process of automotive millimeter-wave radar. However, amplitude-phase distortion resulting from non-ideal electronic components can impact its accuracy simulating real traffic targets. This paper analyzes individual effects amplitude phase on range profile simulated targets RTS. Results be used for design RTS systems.

Pantograph arcing is a key electromagnetic disturbance source to affect train control system in high-speed railway. Since the characteristics of pantograph are related speed, it necessary investigate effective numerical modeling and measurement method. However, due uncontrollable speed during onsite measurement, difficult study radiated from corresponding repeat same measurement. Therefore, method that combines reverberation chamber measurements for calculating railway proposed. Numerical...

Joint transmission is one of the major schemes in Coordinated multipoint (CoMP) transmission/reception systems for Long term evolutionadvanced (LTE-A). Due to different distances between User equipments (UE) and Base stations (BS), signals are not able arrive at receiver with perfect synchronization, which implies that reception UE asynchronous. This paper presents an evaluation on asynchronous multi-cell downlink joint using our LTE-based CoMP simulator. Then, due reception, we propose...

Electromagnetic interference (EMI) produced by series arc fault has long been a concern in dc distribution systems. As EMI may lead to serious safety risks, it is important detect and predict disturbance for management purposes. This article proposes deep-learning-based approach diagnosis circuit behavior prediction. Using time–frequency slices generated from power supply-side signals as reference input, the proposed method capable of extracting features with feature extractor. The two-step...

Many efforts have been taken in recent years to push atomic gravimeters toward practical applications. We demonstrate an gravimeter named NIM-AGRb2 that is transportable and suitable for high-precision gravity measurements. Constraint-structured active vibration isolation (CS-AVI) used reduce the ground noise. The constraint structure CS-AVI ensures platform only has vertical translation, with all other degrees of freedom (DoFs) being constrained. Therefore, stability enhanced. With...

Due to the necessity realize “building a strong transportation nation”, construction of intermodal is based on information resource integration diverse transport systems. To ensure data security during interaction between different modes, as well effect application, status entities and flow in network should be supervised throughout. Therefore, an evaluation framework comprehensive trust proposed this paper. With feature analysis big data, quality assessment conducted by three-dimensional...

The China high-speed trains use cable trays to neatly arrange the cables running through distributed systems. On one hand, they protect against external electromagnetic interference and reduce radiation from cables. other create waveguide structures that affect coupling among inside trays. To simplify analysis for going a tray, lumped circuit model was built using admittance blocks extracted mixed-potential integral equation (MPIE) formulation. In MPIE formulation, either half-free space or...

From technology importation to independent innovation, Chinese High speed railway (HSR) has been rapidly developed in the past a few years. However, this development mode introduces very complex electromagnetic environment of HSR system, which is based on various equipment with different Electromagnetic compatibility (EMC) design. Consequently, suppression disturbance and protection becoming an urgent issue for HSR. The characteristics traction power supply technology, train operation...

Pantograph arcing caused by Off-line of pantograph-catenary (OLPC) will generate Electromagnetic disturbance (EMD), which affect train control system and communication system. This paper proposes a simplified model the pantograph to investigate propagation characteristics EMD from OLPC in viaduct scenario, containing attenuation law transverse longitudinal directions. As result, electric field strength increases with distance direction 10m 30m is different ground scenario. The fitting...

A capacitive loaded quasi-elliptic function microstrip filter on GSM-R with the bandwidth of 4 MHz, fractional <0.5%, are designed. To demonstrate proposed design, a four-order bandpass was designed and fabricated.

Finding a free road side parking in urban area is considered as one of the most challenging driving tasks, especially for autonomous vehicles with limited sight (e.g. short range sensing) and brain (compared human beings). To assist vehicle area, we propose novel scheme CrowdParking, which applies crowdsourcing vehicular fog computing to collect information from vehicles, locate spaces crowdsourced data. We also explore variation availability real world data set find that specific lot has...

The GSM-R become the communication system for data and voice transmission throughout China Rail Network. However, communications can be significantly disturbed by electromagnetic (EM) interferences produced High-Powered catenary system. Our measurements highlighted that EM when sparks occur due to poor contact between pantograph radiate considerable energy in band. This paper will then present main characteristics of these transient analyze relevance characterization methods order establish...

This article concentrates on the steady-state thermal characteristics of Axial-Radial Flux-Type Permanent Magnet Synchronous Motor (ARFTPMSM). Firstly, three-dimensional mathematical models for electromagnetic calculation and analyses are established, machine loss, including stator armature winding rotor axial structure loss is calculated by using time-step Finite Element Method (FEM). Then, distribution assigned as heat source calculation. Secondly, model also established. The assumptions...

Pantograph arcing is the main EMC interference source in a high speed train. This paper describes laboratory replica of pantograph which can be operated reverberation chamber. The set-up has been verified by numerical modeling to show it suitable replace real for investigating radiation properties arcing. Some initial measurements have taken results that chamber working well measure power radiated from arc generated set-up.

Cobalt porphyrin and similar metalloporphyrins (MPs) were initially used in the colorimetric sensor array (CSA) system for quality assurance control beverage food. In order to design a proper CSA sensor, density functional theory method with B3LYP/LANL2DZ basis set was performed investigate influences of axial ligand, substituent group volatile organic compounds (VOCs) on binding process. Ground state structure determined at three spin states: low, intermediate high states, based relative...

Frequency measurements for complex single-tone signals under additive Gaussian noise cover extensive engineering fields. Existing direct discrete Fourier transform (DFT) interpolation methods suffer both degraded accuracies noisy conditions and biased estimation performances a restricted number of samples. To address these problems, this article proposes fast accurate frequency scheme using two-sample DFT interpolation. First, work introduces deviation detector that can exactly recognize the...

The balise transmission system (BTS) is an automatic identification for vehicle–ground communication based on radio frequency (RFID) technology. electromagnetic coupling characteristics of BTS have a very important effect the quality uplink telegram signals. However, signal problems often occur due to unreasonable installation mode or parameter setting. In order solve these problems, it necessary fully discuss BTS. this paper, process energy and data between onboard antenna unit was analyzed...

In this paper, based on the measured data at Wuhan-Guangzhou high speed railway, statistics characteristics of mobile fading channel including long-term and short-term in environment are presented. The measurement campaigns were conducted GSM-R downlink band. experimental was analyzed to provide path loss model probability density functions (PDF) signal amplitude, delay statistics, number paths power statistics. From these it is shown that index railway area n=2~5 with standard deviation...

Long Term Evolution (LTE) has the characteristics of high speed, low delay, mobility and security. The International Railway Union (UIC) confirmed LTE as next generation railway wireless communication technology, while 400 MHz frequency band is currently available a resource in China. However, considering that disturbance generated by pantograph arcing strong band, it necessary to study LTE-R system under radiation disturbance. In this paper, are studied theoretical numerical simulation...

In this paper, a miniaturized planar rat-race coupler is proposed to achieve arbitrary power division ratio and harmonic suppression performance simultaneously. It consists of six enhanced T- shaped line sections. The T-shaped lines can be equivalent electrical length rather than the conventional λ/4 lines. explicit design formulas are derived characteristic impedances variations with freedom variable discussed. Simulated experimental results show over �35 dB, while maintaining at...