- 标题
- 摘要
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- 实验方案
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Fast modeling of electromagnetic scattering from 2D electrically large PEC objects using the complex line source type Green's function
摘要： This study introduces an alternative approach to the numerical solution of two-dimensional (2D) electromagnetic scattering problems by a numerical method of moments (MoM). The real source position vector is replaced by a complex quantity, then Green’s function generates a complex source point beam, therefore the interactions between the far zone elements in the impedance matrix are neglected, except the basis functions near to the edges, strongly localizing the impedance matrix. The memory storage increases with the number of edges, but for a fixed number of the edges, it is linearly proportional with N, i.e. O(N). Consequently, the overall running time can be drastically reduced and the far zone scattering pattern and the near field can be found. The proposed procedure is first explained for the single perfectly electrically conducting (PEC) strip geometry, then extended to the scattering by 2D PEC objects with closed polygonal cross-sections. Numerical results are presented for a strip and a square cylinder in both polarizations. The relative errors are also compared with the standard MoM.
关键词： computational electromagnetics,radar cross section,Electromagnetic scattering
更新于2025-09-23 15:23:52
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[IEEE 2018 International Conference on Radar (RADAR) - Brisbane, Australia (2018.8.27-2018.8.31)] 2018 International Conference on Radar (RADAR) - Radar Cross Section of Modified Target Using Gaussian Beam Methods: Experimental Validation
摘要： The aim of this paper is to study the Radar Cross Section (RCS) of modified radar targets (plate with notch) using Gaussian Beam techniques. The Gaussian methods used in this work are Gaussian Beam Summation (GBS) and Gaussian Beam Launching (GBL). We establish the theoretical formulation of the GBS and GBL techniques and analyze the influence of the main Gaussian beam parameters on the variation of the scattered field. Then, we present the simulations of RCS. The numerical results are compared with PO, MoM methods, and also with experimental measurements performed in the anechoic chamber at Lab-STICC (ENSTA Bretagne).
关键词： Radar Cross Section (RCS),Physical Theory of Diffraction (PTD),Physical Optic (PO),Gaussian Beam Summation (GBS),Gaussian Beam Launching(GBL),Method of Moment (MoM)
更新于2025-09-23 15:22:29
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A Domain Decomposition Finite Element Method for Modeling Electromagnetic Scattering from Rough Sea Surfaces with Emphasis on Near-Forward Scattering
摘要： A high fidelity full-wave simulator is presented to perform numerical experiments for rough sea scattering problem by considering different polarizations, frequencies, grazing angles, wind speeds and sea surface spectra. The simulator is based on a novel Finite Element Domain Decomposition (FEDD) method for solving the problem of two dimensional electromagnetic scattering over one-dimensional sea surface. This non-iterative method partitions the computational domain into a number of overlapping subdomains and solves each domain individually by employing the Locally-Conformal Perfectly Matched Layer (LC-PML) at the truncation boundaries. LC-PML has a unique feature such that it can be applied to irregular domains on the contrary to standard PML methods, and hence inspired the birth of FEDD. The FEDD method is used at each Monte Carlo realization corresponding to a sample from random rough surfaces, and decreases the computational load especially for electrically-large problems. The accuracy and computational efficiency of the method is investigated through several simulations. Using the FEDD method, the statistical behavior of the bistatic Radar Cross Section (RCS) is obtained for both horizontal and vertical polarizations. A special emphasis is given to forward-scattered RCS and the mean reflection coefficient for sea surface especially at low grazing angles, and it is shown that the simulator produces results in agreement with the Ament and Miller-Brown approximations, and experimental data, proving the reliability of the simulation approach. The results are also compared with the standard finite element method and method of moments. Rough sea surfaces are created by using both Pierson-Moskowitz and Elfouhaily spectra.
关键词： Locally-Conformal Perfectly Matched Layer (PML),forward scattering,sea surface,Domain decomposition,Monte Carlo,rough surface scattering,Finite Element Method (FEM),propagation,reflection coefficient,bistatic Radar Cross Section (RCS),multipath
更新于2025-09-23 15:21:21
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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
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[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia, Spain (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Electromagnetic Modeling of Ships in Maritime Scenarios: Geometrical Optics Approximation
摘要： Global Navigation Satellite System-Reflectometry (GNSS-R), is succesfully employed for ocean altimetric and scatterometric applications. Recently, it has been suggested that GNSS-R can also be used for ship detection applications. To this purpose, an accurate electromagnetic modeling of the bistatic radar cross section of a ship lying over the sea surface would be very helpful. However, existing models are typically limited to monostatic configurations, thus restricting their applicability in multistatic scenarios, such as GNSS-R systems. In this work, we show a procedure to determine the bistatic radar cross section of a ship target, under the geometrical optics approximation. Numerical results show the impact of the geometry of acquisition and polarization on the bistatic radar cross section.
关键词： geometrical optics,radar cross section,Electromagnetic scattering,ship detection
更新于2025-09-23 15:21:21
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Radar cross-section of pedestrians in the low-THz band
摘要： Low-terahertz (THz) (above 150?GHz) radar sensing is one of the promising technologies to provide safe navigation for autonomous cars due to its expected high-resolution imaging capability. It is anticipated that for robust operation at high levels of autonomy the sensor suite should provide a fusion of video and radar data and its efficiency depends on radar ability to deliver a resolution high enough to be compatible with that of the optical image. Performance of low-THz radar, capable to deliver required resolution, is considered in this study, with the focus on reflectivities of pedestrians at frequencies within the low-THz region – 150 and 300?GHz. Backscatter returns are collected in a controlled environment at a number of frequency bands and at different aspect angles. Measurement methodology is presented and several indicators of reflectivities are calculated. Results are compared with values of radar cross-section reported for current automotive frequency standards 24 and 77?GHz. The effect of clothing on reflectivities is also considered in this study.
关键词： autonomous cars,Low-terahertz radar,automotive sensing,pedestrian detection,radar cross-section
更新于2025-09-23 15:21:01
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[IEEE 2019 Radiation and Scattering of Electromagnetic Waves (RSEMW) - Divnomorskoe, Russia (2019.6.24-2019.6.28)] 2019 Radiation and Scattering of Electromagnetic Waves (RSEMW) - Diffraction of a Plane E-polarized Wave on Waveguide Van Atta Array, Placed on the Surface of PEC Cylinder
摘要： The two-dimensional problem of the diffraction of a plane E-polarized wave on a Van Atta waveguide array located on the surface of a perfectly-conducting circular cylinder is solved. The radiators in the form of open ends of waveguides are connected by plane-parallel multimode waveguides of uniform length. The task is reduced to solving an integral equation for the magnetic field vector over the entire surface of the cylinder, which is reduced to an infinite system of linear algebraic equations for the coefficients of the expansion of the magnetic field vector for a complex Fourier series in azimuthal harmonics. The solution of the equation was received strictly and approximately. An expression for the scattering diagram is obtained, represented through the geometrical parameters of the structure.
关键词： reflected wave,Van Atta array,scattering diagram,radar cross section,waveguide
更新于2025-09-23 15:21:01
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High-Gain Circularly Polarized Fabry–Pérot Patch Array Antenna with Wideband Low-Radar-Cross-Section Property
摘要： In this paper, we explore the adoption of a chessboard polarization conversion metasurface (CPCM) for constructing a low-radar-cross-section (RCS), high-gain circularly polarized (CP) patch array antenna. The proposed CPCM is used as the polarization conversion metasurfaces’ chessboard configuration, which consists of adjacent two-layer substrates that have three metallic models. Low RCS is achieved by 180° (±30°) reflection phase variations of two adjoining PCMSs. Gain enhancement is achieved by adopting a Fabry–Pérot cavity constituted by a PCM and the antenna’s ground. The antenna with a CPCM that operates at X/Ku band, excited by the feeding network that is rotated sequentially, is measured and fabricated. The patch array antenna impedance bandwidth based on PCM was measured as 3.3 GHz (9.5–12.8 GHz) with a 3-dB axial ratio bandwidth of 11.6% and a high gain of 13.4 dBiC (9.5–12 GHz), more than 2.5 dB higher compared with a patch antenna without a PCM. In addition, the patch array antenna produced a useful wideband RCS decrease in the operational bandwidth from 9 to 13 GHz.
关键词： low radar cross-section,dual patch,polarization conversion metasurface,circularly polarized
更新于2025-09-19 17:15:36
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Gain enhancement and RCS reduction of CP patch antenna using partially reflecting and absorbing metasurface
摘要： This paper presents a novel partially reflecting and absorbing metasurface (PRAM) in order to reduce Radar Cross Section (RCS) and enhance the gain of the circularly polarized patch antenna. The unit cell of PRAM consists of two stacked substrates with metallic patterns, which is used to design absorbing surface (AS) and partial reflecting surface (PRS). The metallic pattern on the top of the two substrates acts as AS and absorbs most of the out of band incoming wave. The bottom surface of the PRAM is used as PRS to construct Fabry-Perot (F-P) resonance cavity with metamaterial ground plane (MGP) for gain enhancement. Simulated and measured results show that the peak gain of the proposed antenna is enhanced by 5.7 dB at 6.6 GHz. The results also show that the impedance bandwidth and 3-dB axial ratio bandwidth of the antenna are also improved by the employment of PRAM. Monostatic RCS of the proposed antenna is significantly reduced in the broad range of 7 to 18 GHz and proposed antenna achieves maximum RCS reduction of 15.6 dB at 14.3 GHz.
关键词： Gain enhancement,circular polarization,partially reflecting and absorbing metasurface (PRAM),radar cross section (RCS)
更新于2025-09-19 17:15:36
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Design and Analysis of Wideband Low-Scattering Endfire Antenna Using Moth Tail-Inspired Metamaterial Absorber and Surface Waveguide
摘要： This paper presents a wideband endfire antenna co-designed with broadband low-scattering characteristics. The wideband reflection and endfire radiation attribute the success to the supported dual-resonance surface waves, and the broadband low scattering owes to the combination of a metamaterial absorber (MA) absorption and an incident penetration of a frequency selective surface (FSS). Based on the transmission line model, a surface waveguide (SWG) which can support dual-resonance surface waves is adopted and analyzed to realize the wideband reflection response (4.95 ~ 6.83 GHz) and endfire radiation. Also, the SWG can be seen as an FSS for the normal incidence. In addition, a wideband MA, which is inspired by the luna moth's escape from bat attack, is designed and integrated with the SWG to realize low back radar cross section (RCS) in the frequency range from 0.5 to 12.5 GHz. The reflection, radiation and scattering performance are validated by the full-wave simulation and experimental verification.
关键词： Frequency selective surface (FSS),radar cross section (RCS),surface wave,moth tail-inspired metamaterial absorber (MA)
更新于2025-09-16 10:30:52