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oe1(光电查) - 科学论文

7 条数据
?? 中文(中国)
  • Finite-Difference Time-Domain Modeling for Electromagnetic Wave Analysis of Human Voxel Model at Millimeter-Wave Frequencies

    摘要: The finite-difference time-domain (FDTD) modeling of a human voxel model at millimeter-wave (mmWave) frequencies is presented. It is very important to develop the proper geometrical and electrical modeling of a human voxel model suitable for accurate electromagnetic (EM) analysis. Although there are many human phantom models available, their voxel resolution is too poor to use for the FDTD study of EM wave interaction with human tissues. In this paper, we develop a proper human voxel model suitable for mmWave FDTD analysis using the voxel resolution enhancement technique and the image smoothing technique. The former can improve the resolution of the human voxel model and the latter can alleviate staircasing boundaries of the human voxel model. Quadratic complex rational function is employed for the electrical modeling of human tissues in the frequency range of 6–100 GHz. Massage passing interface-based parallel processing is also applied to dramatically speed up FDTD calculations. Numerical examples are used to illustrate the validity of the mmWave FDTD simulator developed here for bio electromagnetics studies.

    关键词: human tissue,electromagnetic wave,Doppler radar,dispersion model,bioelectromagnetics,Finite-difference time-domain (FDTD) method,parallel processing

    更新于2025-09-23 15:23:52

  • RESEARCH ON MINIMUM ENERGY EXCITED TO PLASMA COATING FOR REDUCING RADAR CROSS SECTION OF TARGET

    摘要: To reduce the radar cross section (RCS) of a target, plasma coating on perfectly electric conducting plate is studied in this paper. Nonuniform helium plasma produced by a minitype solid rocket engine is with collisional and unmagnetized. Energy excited for generating helium plasma is investigated. Based on the collisional, unmagnetized, and cold plasma model, backscattering RCS is computed by using ?nite-di?erence time-domain method. Principle of RCS reduction is explained. To ?nd minimum input energy while RCS reduced, relationship between input power and RCS reduction is discussed, and numerical optimization is also implemented. We can identify optimal parameters and choose the best electron density pro?le under condition of given input power level.

    关键词: Radar Cross Section (RCS),Plasma Coating,Input Power,Electron Density,Finite-Difference Time-Domain (FDTD) Method

    更新于2025-09-23 15:21:21

  • Material distributive topology design of UWB antenna using parallel computation of improved BPSO with FDTD

    摘要: In this article, the material distributive topology-based design optimization of ultra-wide band (UWB) antenna is proposed by using improved binary particle swarm optimization (BPSO) with finite difference time domain (FDTD) method. In the improved BPSO implementation, the velocity of each particle is calculated based on complete set of bits of particle position vector. The V-shaped transfer function is employed to transform all real values of velocities to values in the interval [0,1]. The fitness function of all the particles in BPSO algorithm are computed parallely by using FDTD simulation. The usage of FDTD and the parallel computation helps in analyzing the broadband frequency characteristics of the antenna with a single simulation run. The return loss of the optimized UWB antenna obtained from FDTD, Computer Simulation Technology (CST) simulation and practical measurement are in good agreement and show good impedance matching.

    关键词: UWB antenna,finite difference time domain (FDTD) method,topology optimization,Binary particle swarm optimization (BPSO)

    更新于2025-09-23 15:21:21

  • [IEEE 2020 IEEE Conference of Russian Young Researchers in Electrical and Electronic Engineering (EIConRus) - St. Petersburg and Moscow, Russia (2020.1.27-2020.1.30)] 2020 IEEE Conference of Russian Young Researchers in Electrical and Electronic Engineering (EIConRus) - The Automated Test Bench for Studying the Parameters of a Laser Beam Near the Surface of Short-Focus Optical System

    摘要: A general framework to combine the finite-difference time-domain (FDTD) and the finite-element time-domain (FETD) formulations, both based on the vector wave equation, is proposed. In contrast to the existing stable hybrid FETD-FDTD, there is no transition layer between two subdomains. In addition, the stability of the proposed approach is analytically proved. This framework allows combining different FDTD and FETD formulations together. Particularly, a fully unconditionally stable hybrid method is proposed, which is proved to be energy conservative too. The key ingredient is a finite-element tearing and interconnecting method for electromagnetic problems with a new interface condition that preserves the stability of the numerical method in each region. Several numerical examples are considered in order to validate the proposed methods. The numerical results match with the reference solutions very well in all cases.

    关键词: Finite-difference time-domain (FDTD) method,finite-element tearing and interconnecting (FETI),nonoverlapping,finite-element time-domain (FETD) method

    更新于2025-09-23 15:21:01

  • Imaginary-distance beam-propagation method based on Yee's mesh in cylindrical coordinates

    摘要: An imaginary-distance beam-propagation method based on Yee’s mesh (ID-YM-BPM) is developed in cylindrical coordinates, in which the mode number of the eigenmode field is strictly considered. The ID-YM-BPM is second-order accurate with respect to the spatial mesh size. A segmented cladding fiber is analyzed, showing good agreement with other methods.

    关键词: imaginary-distance procedure,Yee’s mesh,beam-propagation method (BPM),finite-difference time-domain (FDTD) method,cylindrical coordinates

    更新于2025-09-23 15:21:01

  • [IEEE 2019 IEEE Innovative Smart Grid Technologies - Asia (ISGT Asia) - Chengdu, China (2019.5.21-2019.5.24)] 2019 IEEE Innovative Smart Grid Technologies - Asia (ISGT Asia) - Research on the Economic Benefit of Energy Storage System Works with Photovoltaic System Considering the Cost of Electricity

    摘要: A general framework to combine the finite-difference time-domain (FDTD) and the finite-element time-domain (FETD) formulations, both based on the vector wave equation, is proposed. In contrast to the existing stable hybrid FETD-FDTD, there is no transition layer between two subdomains. In addition, the stability of the proposed approach is analytically proved. This framework allows combining different FDTD and FETD formulations together. Particularly, a fully unconditionally stable hybrid method is proposed, which is proved to be energy conservative too. The key ingredient is a finite-element tearing and interconnecting method for electromagnetic problems with a new interface condition that preserves the stability of the numerical method in each region. Several numerical examples are considered in order to validate the proposed methods. The numerical results match with the reference solutions very well in all cases.

    关键词: Finite-difference time-domain (FDTD) method,finite-element tearing and interconnecting (FETI),nonoverlapping,finite-element time-domain (FETD) method

    更新于2025-09-16 10:30:52

  • One-Step Leapfrog ADI-FDTD Method Using the Complex-Conjugate Pole-Residue Pairs Dispersion Model

    摘要: A novel one-step leapfrog alternating-direction-implicit finite-difference time-domain method for the modeling of dispersive media described by the complex-conjugate pole-residue pairs model is proposed. The efficiency of the technique is demonstrated in benchmark numerical examples.

    关键词: finite-difference time-domain (FDTD) method,leapfrog alternating-direction-implicit (LADI) scheme,Dispersive media

    更新于2025-09-11 14:15:04