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Performance Study of MIMO-OSTBC Parallel Relay FSO System Based on GFDM

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Chinese Journal of Electronics 2024年第2期33卷 564-572页

作者： Rui ZHOU Yong WANG Yi WANG Key Laboratory of Electromagnetic Wave Information Technology and Metrology of Zhejiang Province College of Information Engineering China Jiliang University State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University

This paper investigates the performance of a new generalized frequency division multiplexing(GFDM)parallel relay free space optical(FSO) communication system using multi-input multi-output(MIMO) orthogonal space-time block codes(OSTBC) scheme. Under the M distribution atmospheric turbulence, taking into account the triple effects of irradiance, pointing errors and path loss, the mathematical expression of system symbol error rate is derived with the help of Meijer G-function. The symbol error performance of GFDM is compared with on-off keying,Gaussian minimum shift keying, polarization shift keying and orthogonal frequency division multiplexing(OFDM)modulation methods. The effects of the MIMO-OSTBC parallel relay scheme on the GFDM system including filter roll down coefficient, the number of transmitting and receiving antennas, the number of relays, normalized beamwidth and jitter variance are analyzed, and the numerical results are verified by monte carlo simulation. This work provides a good foundation for engineering applications.

关键词： monte carlo methods Transmitting antennas Symbols Receiving antennas Modulation Jitter Transceivers

Optical Space Time Pulse Position Modulation over Exponential Weibull Turbulence Channel

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Chinese Journal of Electronics 2024年第2期33卷 527-535页

作者： Yue ZHANG Huiqin WANG Xuemei MA Minghua CAO Qingbin PENG School of Computer and Communication Lanzhou University of Technology School of Foreign Languages Lanzhou University of Technology

An optical space time pulse position modulation(OSTPPM) scheme is proposed to satisfy the communication requirement of high transmission rate and better reliability. For the OSTPPM scheme, an improved threshold judgment-based orthogonal matching pursuit(IT-OMP) algorithm with low-complexity and near optimal performance is proposed. The average bit error rate of OSTPPM-IT-OMP scheme is investigated over the exponential Weibull channel, and its analytical expression is verified via monte carlo simulation. With the same simulation parameters, the signal to noise ratio of(4,4,2)-OSTPPM-IT-OMP is respectively 3.75 d B and 8.5 d B better than that of spatial pulse position modulation(SPPM) scheme and generalized spatial pulse position modulation(GSPPM)scheme at a bit error rate of 1 × 10-3. With the same transmission bits per symbol, the computational complexity of(3,4,2)-OSTPPM-IT-OMP scheme is reduced by 90.47% and 75.4% compared with(16,4,2)-SPPM and(5,4,2)-GSPPM schemes, respectively.

关键词： Wireless communication Wireless sensor networks monte carlo methods Bit error rate Matching pursuit algorithms Adaptive optics Optical modulation

Recent advances in glinty appearance rendering

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Computational Visual Media 2022年第4期8卷 535-552页

作者： Junqiu Zhu Sizhe Zhao Yanning Xu Xiangxu Meng Lu Wang Ling-Qi Yan Shandong University JinanChina University of California Santa BarbaraUSA

The interaction between light and materials is key to physically-based realistic ***,it is also complex to analyze,especially when the materials contain a large number of details and thus exhibit"glinty"visual *** methods of producing glinty appearance are expected to be important in next-generation computer *** provide here a comprehensive survey on recent glinty appearance *** start with a definition of glinty appearance based on microfacet theory,and then summarize research works in terms of representation and practical *** have implemented typical methods using our unified platform and compare them in terms of visual effects,rendering speed,and memory ***,we briefly discuss limitations and future research *** hope our analysis,implementations,and comparisons will provide insight for readers hoping to choose suitable methods for applications,or carry out research.

关键词： glinty appearance monte carlo methods rendering

Solving quantum rotor model with different monte carlo techniques

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Chinese Physics B 2022年第4期31卷 208-218页

作者： Weilun Jiang Gaopei Pan Yuzhi Liu Zi-Yang Meng Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100190China Department of Physics and HKU-UCAS Joint Institute of Theoretical and Computational Physics The University of Hong KongPokfulam RoadHong KongChina Songshan Lake Materials Laboratory Dongguan 523808China

We systematically test the performance of several monte carlo update schemes for the(2+1)d XY phase transition of quantum rotor *** comparing the local Metropolis(LM),LM plus over-relaxation(OR),Wolff-cluster(WC),hybrid monte carlo(HM),hybrid monte carlo with Fourier acceleration(FA)schemes,it is clear that among the five different update schemes,at the quantum critical point,the WC and FA schemes acquire the smallest autocorrelation time and cost the least amount of CPU hours in achieving the same level of relative error,and FA enjoys a further advantage of easily implementable for more complicated interactions such as the long-range *** results bestow one with the necessary knowledge of extending the quantum rotor model,which plays the role of ferromagnetic/antiferromagnetic critical bosons or Z_(2)topological order,to more realistic and yet challenging models such as Fermi surface Yukawa-coupled to quantum rotor models.

关键词： monte carlo methods

A survey on rendering homogeneous participating media

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Computational Visual Media 2022年第2期8卷 177-198页

作者： Wenshi Wu Beibei Wang Ling-Qi Yan School of Computer Science and Engineering Nanjing University of Science and TechnologyNanjingChina University of California Santa BarbaraUSA

Participating media are frequent in real-world scenes,whether they contain milk,fruit juice,oil,or muddy water in a river or the *** light interacts with these participating media in complex ways:refraction at boundaries and scattering and absorption inside *** radiative transfer equation is the key to solving this *** are several categories of rendering methods which are all based on this equation,but using different *** this paper,we introduce these groups,which include volume density estimation based approaches,virtual point/ray/beam lights,point based approaches,monte carlo based approaches,acceleration techniques,accurate single scattering methods,neural network based methods,and spatially-correlated participating media related *** well as discussing these methods,we consider the challenges and open problems in this research area.

关键词： participating media monte carlo methods rendering volume density estimation

Passive attitude stabilization of ionic-wind-powered micro air vehicles

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Chinese Journal of Aeronautics 2023年第7期36卷 412-419页

作者： Hengyu ZHANG Jiaming LENG Zhiwei LIU Mingjing QI Xiaojun YAN School of Energy and Power Engineering Beihang UniversityBeijing 100191China

The ionic-wind-powered Micro Air Vehicles(MAVs)can achieve a higher thrust-toweight ratio than other ***,this kind of MAV has not yet achieved controlled flight because of the unstable thrust produced by the ionic wind and the dynamic instability related to the small *** this paper,a passive attitude stabilization method of the ionic-wind-powered MAV using air dampers is *** key factors that influence the performance of the air dampers,including the layout,position,and area of the air dampers,are theoretically *** appropriate optimal position of the air dampers is also obtained by monte carlo stochastic *** the proposed passive attitude stabilization method is applied to the ionic-wind-powered MAVs of different wingspan(2 cm and 6.3 cm).Finally,the experimental results show that using the proposed method,attitude stabilization is achieved for the first time for the ionic-wind-powered ***,the altitude control of an ionic-wind-powered MAV with a wingspan of 6.3 cm is also demonstrated.

关键词： Air dampers Altitude control Ionic wind propulsion Micro air vehicle monte carlo methods Stability

Track-Oriented Marginal Poisson Multi-Bernoulli Mixture Filter for Extended Target Tracking

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Chinese Journal of Electronics 2023年第5期32卷 1106-1119页

作者： DU Haocui XIE Weixin LIU Zongxiang LI Liangqun ATR Key Laboratory Shenzhen University Guangdong Key Laboratory of Intelligent Information Processing Shenzhen University

In this paper, we derive and propose a track-oriented marginal Poisson multi-Bernoulli mixture(TO-MPMBM) filter to address the problem that the standard random finite set filters cannot build continuous trajectories for multiple extended targets. First, the Poisson point process model and the multi-Bernoulli mixture(MBM) model are used to establish the set of birth trajectories and the set of existing trajectories, ***, the proposed filter recursively propagates the marginal association distributions and the Poisson multiBernoulli mixture(PMBM) density over the set of alive trajectories. Finally, after pruning and merging process,the trajectories with existence probability greater than the given threshold are extracted as the estimated target trajectories. A comparison of the proposed filter with the existing trajectory filters in two classical scenarios confirms the validity and reliability of the TO-MPMBM filter.

关键词： Target tracking Uncertainty monte carlo methods Trajectory tracking Filtering Merging Filtering algorithms

An Improved Path Delay Variability Model via Multi-Level Fan-Out-of-4 Metric for Wide-Voltage-Range Digital CMOS Circuits

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Chinese Journal of Electronics 2023年第2期32卷 375-388页

作者： CUI Yuqiang SHAN Weiwei DAI Wentao LIU Xinning GUO Jingjing CAO Peng National ASIC System Engineering Research Center Southeast University Cadence Design Systems Inc. Nanjing University of Posts and Telecommunications

In advanced CMOS technology, process,voltage, and temperature(PVT) variations increase the paths’ latency in digital circuits, especially when operating at a low supply voltage. The fan-out-of-4 inverter chain(FO4 chain) metric has been proven to be a good metric to estimate the path’s delay variability, whereas the previous work ignored the non-independent characteristic between the adjacent cells in a path. In this study,an improved model of path delay variability is established to describe the relationship between the paths’ max-delay variability and an FO4 chain, which is based on multilevel FO4 metric and circuit-level parameters knobs(i.e., cell topology and driving strength) of the first few cells. We take the slew and load into account to improve the accuracy of this framework. Examples of 28 nm and40 nm digital circuits show that our model conforms with monte carlo simulations as well as fabricated chips’ measurements. It is able to model the delay variability effectively to speed up the design process with limited accuracy loss. It also provides a deeper understanding and quick estimation of the path delay variability from the near-threshold to nominal voltages.

关键词： Semiconductor device modeling monte carlo methods Temperature Computational modeling Inverters Delays Topology

Modelling the interaction of the Astro Bio Cube Sat with the Van Allen's Belt radiative field using monte carlo transport codes

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Radiation Detection Technology and methods 2022年第2期6卷 262-279页

作者： N.Burgio L.Cretara M.Corcione M.Frullini L.lannascoli A.Nascetti A.Santagata G.Palmerini A.Quintino J.R.Brucato A.Meneghin D.Paglialunga ENEA FSN-FISS-RNRC.R.CasacciaRomeItaly DIAEE Sapienza UniversitàDi RomaVia Eudossiana 1800184 RomeItaly School of Aerospace Engineering Sapienza University of RomeVia Salaria 85100138 RomeItaly INAF-Astrophysical Observatory of Arcetri L.go E.Fermi 550125 FlorenceItaly

Purpose The AstroBio Cube Satellite(ABCS)will deploy within the inner Van Allen belt on the Vega C Maiden Flight launch opportunity of the European Space *** this altitude,ABCS will experience radiation doses orders of magnitude greater than in low earth orbit,where CubeSats usually *** paper aims to estimate the irradiation effect on the ABCS payload in the orbital condition,their possible mitigation designing shielding solutions and performs a preliminary representativity simulation study on the ABCS irradiation with fission neutron at the TAPIRO(TAratura Pila Rapida Potenza 0)nuclear research reactor facility at *** We quantify the contributions of geomagnetically trapped particles(electron and proton),Galactic Cosmic Rays(GCR ions),Solar energetic particle within the ABCS orbit using the ESA's SPace ENVironment information ***(Fluktuierende Kaskade-Fluctuating Cascade)code models the ABCS interaction with the orbital *** We found a shielding solution of the weight of 300 g constituted by subsequent layers of tungsten,resins,and aluminium that decreases on average the 20%overall dose rate relative to the shielding offered by the only satellite's ***,simulations of neutron irradiation of the whole ABCS structure within the TAPIRO's thermal column cavity show that a relatively short irradiation time is requested to reach the same level of 1 MeV neutron Silicon equivalent damage of the orbital *** The finding deserves the planning of a future experimental approach to confirm the TAPIRO's performance and establish an irradiation protocol for testing aerospatial electronic components.

关键词： Galactic cosmic rays and solar energetic particles Spacecraft shielding Dosimetry monte carlo methods MCNP and FLUKA