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propagation modeling of ocean-scattered low-elevation GPS signals for maritime tropospheric duct inversion

Chinese Physics B 2012年第10期21卷 600-613页

作者：张金鹏吴振森赵振维张玉生王波 School of Science Xidian University China Research Institute of Radio Wave Propagation Institute of Oceanographic Instrumentation

The maritime tropospheric duct is a low-altitude anomalous refractivity structure over the ocean surface,and it can significantly affect the performance of many shore-based/shipboard radar and communication *** propose the idea that maritime tropospheric ducts can be retrieved from ocean forward-scattered low-elevation global positioning system（GPS） *** is accomplished by matching the measured power patterns of the signals to those predicted by the forward propagation model as a function of the modified refractivity *** the basis of a parabolic equation method and bistatic radar equation,we develop such a forward model for computing the trapped propagation characteristics of an ocean forward-scattered GPS signal within a tropospheric duct.A new GPS scattering initial field is defined for this model to start the propagation modeling.A preliminary test on the performance of this model is conducted using measured data obtained from a 2009-experiment in the South China *** demonstrate that this model can predict GPS propagation characteristics within maritime tropospheric ducts and serve as a forward model for duct inversion.

关键词： global positioning system ocean surface scattering propagation modeling tropospheric duct inversion

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propagation modeling of active P2P worms based on ternary matrix

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JOURNAL OF NETWORK AND COMPUTER APPLICATIONS 2013年第5期36卷 1387-1394页

作者： Chen, Ting Zhang, Xiao-song Li, Hong-yuan Wang, Dong Wu, Yue Univ Elect Sci & Technol China Sch Comp Sci & Engn Chengdu 611731 Peoples R China

propagation modeling of worms has become an attractive research field in recent years since it facilitates worm prediction, detection, analysis and prevention etc. In this work, we propose a novel ternary-matrix-based model to describe the propagation trend of active P2P worms. Compared to existing logic-matrix-based models, our model takes the time lags into consideration by introducing new states and special matrix operations. Our model is easy of derivation and deployment because it confines derivation process to pure matrix operations. Moreover, two other advantages of our model are fully explored. One is expressiveness: (1) practical P2P topology can be modeled in the topology matrix;(2) the state of any node can be identified at any time;(3) and the attack path of any node can be backtracked in linear time. Flexibility is the other merit: our model can adapt to different scenes by changing the related parameters, particularly our model is general for different kinds of time lags and P2P topologies. (C) 2013 Elsevier Ltd. All rights reserved.

关键词： Active P2P worms propagation modeling Ternary matrix Time lags Expressiveness Flexibility Ease of derivation and deployment

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propagation modeling of an L-shaped Structure: What Happened when its Width Shrank 5

Propagation Modeling of an L-shaped Structure: What Happened...

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IEEE 5th Asia-Pacific Conference on Antennas and propagation (APCAP)

作者： Lim, Soo Yong Soo, Qi Ping Lim, David Wee Gin Univ Nottingham Dept Elect & Elect Engn Malaysia Campus Semenyih Malaysia

ISBN: (纸本)9781467372374

Ray tracing method has conventionally played an important role in radio propagation modeling, which outputs an estimation of signal strength given certain input parameters. Being a time-honored method, ray tracing is expected to continue to play an important role in next generation propagation modeling. In this paper, we place our focus on a narrow L-shaped structure which oftentimes at first glance appeared simple, yet presents technical complexity that even commercial propagation tool might fail to yield accurate prediction results. The L-shaped structure under scrutiny has a very narrow width, which found its applications in a wide variety of scenarios, ranging from mining and tunnel activities, to speleology and spelunking exploration, and others. Our findings suggest that contrary to what is commonly perceived, in the non-line-of-sight (NLoS) section of the L-shaped structure, reflection turned out to be a very complex propagation mechanism when the width of the structure is very narrow. Instead, diffraction, which in many instances is ignored due to its mathematical complication, emerged as one alternative propagation mechanism that should be explored.

关键词： propagation modeling ray tracing radio propagation

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propagation modeling and Analysis of Incidental Topics in Blogosphere

Propagation Modeling and Analysis of Incidental Topics in Bl...

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3rd International Conference on Online Communities and Social Computing held at the 13th International Conference on Human-Computer Interaction

作者： Zhao, Li Yuan, Ruixi Guan, Xiaohong Li, Mingyang Tsinghua Univ Ctr Intelligent & Networked Syst Beijing 100084 Peoples R China

ISBN: (纸本)9783642027734

Blog has become one of the most important media among the general public, and the propagation modeling of incidental topics in blogosphere is of great interest in social network studies. Most existing analysis methods are based on the infection models in epidemiology. However, many of these models are inconsistent with the widely observed power-law decay of the propagation velocity. In this paper, the propagation of incidental topics is described by a susceptible infection (SI) model based on the individual fitness. It is proved that the propagation velocity will asymptotically drop with power-law if the fitness density function satisfies certain conditions. Moreover, if the individual fitness is of uniform distribution, analytical solution of propagation velocity can be obtained based on our model. Model verifications are performed on the data froth several widely discussed popular topics in Sina Blog and the results show that our model is consistent with the actual propagations.

关键词： propagation modeling blogosphere SI model fitness power-law decay

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propagation modeling and analysis of viruses in P2P networks

Propagation modeling and analysis of viruses in P2P networks

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7th International Conference on Machine Learning and Cybernetics

作者： Feng, Chao-Sheng Qin, Zhi-Guang Cuthbet, Laurence Tokarchuk, Laurissa Univ Elect Sci & Technol China Sch Comp Sci & Engn Changchun 610054 Peoples R China Univ London Dept Elect Engn London WC1E 7HU England Sichuan Normal Univ Sch Comp Sci Chengdu 610068 Peoples R China

ISBN: (纸本)9781424420957

To counter the attacks of virus in P2P file-sharing networks, the model of virus propagation in P2P networks is proposed based on deep analysis on the features of rile sharing and virus propagation. In order to examine the effects of different parameters in this model, large scale simulating experiments are carried out. The numerical analysis on the impact of P2P-related factors such as number of initially infected peers, downloading rate, recovery rate, etc, shows that attack performance of viruses is very sensitive to P2P system parameters.

关键词： viruses propagation modeling P2P networks file-sharing simulation

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propagation modeling for Physically Large Arrays: Measurements and Multipath Component Visibility

Propagation Modeling for Physically Large Arrays: Measuremen...

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Joint European Conference on Networks and Communications / 6G Summit (EuCNC/6G Summit)

作者： Wilding, Thomas Deutschmann, Benjamin J. B. Nelson, Christian Li, Xuhong Tufvesson, Fredrik Witrisal, Klaus Graz Univ Technol Graz Austria Lund Univ Lund Sweden

ISBN: (纸本)9798350311020

This paper deals with propagation and channel modeling for physically large arrays. The focus lies on acquiring a spatially consistent model, which is essential, especially for positioning and sensing applications. Ultra-wideband, synthetic array measurement data have been acquired with large positioning devices to support this research. We present a modified multipath channel model that accounts for a varying visibility of multipath components along a large array. Based on a geometric model of the measurement environment, we analyze the visibility of specular components. We show that, depending on the size of the reflecting surface, geometric visibility and amplitude estimates obtained with a super-resolution channel estimation algorithm show a strong correspondence. Furthermore, we highlight the capabilities of the developed synthetic array measurement system.

关键词： propagation modeling radio measurements radio positioning

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propagation modeling and Placement Algorithms for Wireless Sensor Networks

Propagation Modeling and Placement Algorithms for Wireless S...

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IEEE International Symposium on Industrial Electronics (ISIE)

作者： Luntovskyy, Andriy Vasyutynskyy, Volodymyr Kabitzsch, Klaus BA Dresden Univ Cooperat Educ Heidepk Str 8 D-01099 Dresden Germany Tech Univ Dresden D-01062 Dresden Germany

ISBN: (纸本)9781424463916

The energy efficiency is critical for application of wireless sensor networks, since it is a main precondition for their long-live functionality, small modification costs and reliability. This paper deals with the placement of wireless nodes based on the modeling of radio wave propagation. The methods are realized in a planning tool CANDY Wireless Site Finder that provides optimized topologies of wireless networks under considering of transmitted power, frequencies, propagation environments (in-door/out-door) and obstacles given in CAD-compatible formats. The tool is integrated in the framework of other CANDY tools aimed to efficient planning of heterogeneous wired and wireless networks.

关键词： CAD-compatible format CANDY wireless site finder tool energy efficiency long-live functionality modification cost network planning network topology placement algorithm planning tool propagation modeling radio wave propagation radiowave propagation reliability telecommunication network planning telecommunication network reliability telecommunication network topology wireless node wireless sensor network wireless sensor networks

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A combined triggering-propagation modeling approach for the assessment of rainfall induced debris flow susceptibility

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JOURNAL OF HYDROLOGY 2017年 550卷 130-143页

作者： Stancanelli, Laura Maria Peres, David Johnny Cancelliere, Antonino Foti, Enrico Univ Catania Dept Civil Engn & Architecture Catania Italy

Rainfall-induced shallow slides can evolve into debris flows that move rapidly downstream with devastating consequences. Mapping the susceptibility to debris flow is an important aid for risk mitigation. We propose a novel practical approach to derive debris flow inundation maps useful for susceptibility assessment, that is based on the integrated use of DEM-based spatially-distributed hydrological and slope stability models with debris flow propagation models. More specifically, the TRIGRS infiltration and infinite slope stability model and the FLO-2D model for the simulation of the related debris flow propagation and deposition are combined. An empirical instability-to-debris flow triggering threshold calibrated on the basis of observed events, is applied to link the two models and to accomplish the task of determining the amount of unstable mass that develops as a debris flow. Calibration of the proposed methodology is carried out based on real data of the debris flow event occurred on 1 October 2009, in the Peloritani mountains area (Italy). Model performance, assessed by receiver-operating-characteristics (ROC) indexes, evidences fairly good reproduction of the observed event.. Comparison with the performance of the traditional debris flow modeling procedure, in which sediment and water hydrographs are inputed as lumped at selected points on top of the streams, is also performed, in order to assess quantitatively the limitations of such commonly applied approach. Results show that the proposed method, besides of being more process-consistent than the traditional hydrograph-based approach, can potentially provide a more accurate simulation of debris-flow phenomena, in terms of spatial patterns of erosion and deposition as well on the quantification of mobilized volumes and depths, avoiding overestimation of debris flow triggering volume and, thus, of maximum inundation flow depths. (C) 2017 Elsevier B.V. All rights reserved.

关键词： Susceptibility assessment Debris flow Triggering modeling propagation modeling TRIGRS Giampilieri

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Ultra Broadband Indoor Channel Measurements and Calibrated Ray Tracing propagation modeling at THz Frequencies

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JOURNAL OF COMMUNICATIONS AND NETWORKS 2013年第6期15卷 547-558页

作者： Priebe, Sebastian Kannicht, Marius Jacob, Martin Kuerner, Thomas Tech Univ Carolo Wilhelmina Braunschweig Inst Nachrichtentech D-38106 Braunschweig Germany Terahertz Commun Lab D-38106 Braunschweig Germany

Ultra broadband communication systems operated at THz frequencies will require the thorough knowledge of the propagation channel. Therefore, an extensive measurement campaign of 50 GHz wide indoor radio channels is presented for the frequencies between 275 and 325 GHz. Individual ray paths are resolved spatially according to angle of arrival and departure. A MIMO channel is recorded in a 2x2 configuration. An advanced frequency domain ray tracing approach is used to deterministically simulate the THz indoor propagation channel. The ray tracing results are validated with the measurement data. Moreover, the measurements are utilized for the calibration of the ray tracing algorithm. Resulting ray tracing accuracies are discussed.

关键词： MIMO channel measurements propagation modeling ray tracing propagation simulations THz communications ultra broadband channel measurements

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A Deep Learning Network Planner: propagation modeling Using Real-World Measurements and a 3D City Model

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IEEE ACCESS 2022年 10卷 122182-122196页

作者： Eller, Lukas Svoboda, Philipp Rupp, Markus TU Wien Inst Telecommun A-1040 Vienna Austria

In urban scenarios, network planning requires awareness of the notoriously complex propagation environment by accounting for blocking, diffraction, and reflection on buildings. To this end, deep learning-based signal-strength prediction directly operating on environmental data has recently gained attention, mainly as a computationally efficient alternative to ray-tracing. Our work combines RSRP measurements from an extensive drive-test campaign in a live 4G network with a 3D city model for the largest real-world assessment of such data-driven schemes to date. We compare three different encodings of the propagation environment and find that a neural network operating on a full 3D representation of the surroundings performs best with an RMSE of 7.06 dB. It is followed by a model using only the direct path profile with 7.78 dB and a reference neural network utilizing a binary line of sight indicator achieving 8.76 dB. The large size of our data set allows us to address several open questions regarding the inner workings of these black box approaches. In particular, we elaborate on different evaluation strategies, highlighting the importance of spatial separation of train and test areas, as the rich environmental data implicitly provides a spatial reference. Through model explainability, we further identify the area along the direct path between the user equipment and the transmitter as the input region with the highest feature importance - questioning the common practice of including large buffer areas. Evaluating the models in scenarios with artificially placed base stations reveals that the measurement campaign offers a sufficient basis for a prototypical network planner. The trained models, which we make publicly available, exhibit the dominant propagation mechanisms in urban areas and generate spatially consistent and physically sound signal-strength maps.

关键词： 5G 6G cellular network planning deep learning drive-test LTE machine learning model explainability pathloss prediction propagation modeling signal-strength maps

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