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In view of the near sea area, the formulae finite depth spectrum is given in the paper, the spectral model under different water depths is obtained, by using Kirchhoff approximation and the modified two-scale method, the scattering coefficient and the Doppler echo signal of near sea area are calculated, the agreement with measured data proved the correctness and validity of the near sea area scattering...
Mounting of the construction element onto the base with two tips in the form of sharpened ends, while the base is supposed to represent the fragment of surrounding surface, is a widely used practice in situation, when calculation or measurement of backscattering pattern of construction element is required. The purpose of the tips introduction is to imitate the mock-up borders placement to infinity...
Surface waveguides (SWGs) are a class of open-boundary structures with the capability of guiding surface waves which are intimately bound to the surface of the structure. One of the most commonly occurring type is the planar structures consisting of periodic subwavelength elements. Due to the capability of controlling the propagation path of surface waves (SWs), SWGs have been employed for the applications...
The theories of rough surface scattering are investigated through analysis of SAR imaging. Typically, scattering analysis based on the data averaged over surface realizations does not provide a detailed description of surface scattering phenomena. The advantages of imaging techniques for improving understanding motivate the use of high resolution imaging for studies of rough surface. Image domain...
We investigate plasmon excitation on the surfaces of a thin metal-film grating, which are sinusoidally modulated with a common period and different initial phases. Employing Yasuura's method of modal expansion, we numerically find the resonance angle, field distribution, power flow in the vicinity of the grating surfaces, and efficiency of propagating orders. By setting the amplitude of the metal-film...
The integral equations (IEs) have demonstrated excellent potentials in analyzing large scale electromagnetic radiation and scattering problems. They stand out for properties like only discretization of the objects' surface, automatic satisfaction of the radiation condition, as well as no numerical dispersion. They are usually solved by the method of moment (MoM) following the Galerkin scheme. When...
Conventional coaxial relativistic backward wave oscillator (CRBWO) usually operates at the quasi-TEM mode, whose intense field mainly focuses on the slow wave structures (SWSs) surface. The intense relativistic electron beam (IREB) to stimulate high power microwave (HPM) is needed to pass through the SWSs surface closely so that intense beam-wave interaction can effectively occur. Such a structure...
We report our recent progress in characterizing sub-bandgap surface-state absorption (SSA) and defect-state absorption (DSA) in foundry-fabricated silicon waveguides and microring resonators in 1310–1550nm wavelengths. While SSA is widely regarded as a fundamental linear absorption loss due to surfaces and interfaces for silicon waveguides and microring resonators, our previous work has shown that...
In this paper, we propose a kind of leaky-wave antenna based on spoof surface plasmon polaritons (SPP) along the metallic wire with gradient radial grooves. Coaxial wire, supporting traditional guided waves, is used to feed the proposed structure. The conversion between coaxial wire and SPP waveguide is achieved by the flaring outer conductor of the coaxial wire and gradient radially corrugated inner...
The surface wave modes on right-handed helically grooved metal wire waveguide and left-handed one were studied and compared. It was found that for the helically grooved waveguide, the normal degenerate HE1 SSPP (spoof surface plasmon polaritons) mode decompose into two opposite circularly polarized modes, i.e., HE − 1 and HE + 1 SSPP modes due to the chirality of helical grooves. The divarication...
Many interesting wave manipulation devices, including illusion devices, have been proposed and realized by transformation optics. Using illusion devices, an object of arbitrary shape can be made to appear like another object. However, there are substantial limitations in current illusion devices based on transformation optics. Firstly, refractive index must be modulated over a large volume, thus,...
Metasurface, an optically thin layer of metarmaterials (MTMs), has recently attracted great interest for its capability to manipulate the phase of a propagating wave [1–3]. Such a surface approach of metamaterials has paved a way to escape from the difficulties in fabricating three-dimension (3D) metamaterials. Recently, optically thin metasurface has been demonstrated to achieve invisibility carpet...
In this paper, PO solution of electromagnetic scattering of anisotropic coating target under point source excitation has been derived. Firstly, According to the tangent plane approximation in the PO field, the high frequency scattering problems of point source excitation infinite plane model coated anisotropic medium can be solved specifically. Secondly, we can expand any scattering wave field including...
An inverse scattering problem of determining the electrical property of an unknown dielectric object is considered. The electromagnetic wave generated by an impressed electric current with a short duration time illuminates the dielectric object. The measured data of the total field, the sum of the incident and scattered fields, over an observation surface S is used to reconstruct the electrical property...
Graphene sheets can support surface plasmon as the Dirac electrons oscillate collectively with electromagnetic waves. Compared with the surface plasmon in conventional metal (e.g., Ag and Au), graphene plasmonic owns many remarkable merits especially in Terahertz and far infrared frequencies, such as deep sub-wavelength, low loss, and high tunability. For graphene coated dielectric nano-scatters,...
The resonance phenomena of surface plasmons have led to a novel class of non-contact, real-time and label-free optical sensors which have become a central tool in biochemical sensing and detection. However, all kinds of surface plasmon resonances are with natively strong non-radiative Drude damping that weakens the resonance and limits the sensing performance fundamentally. We demonstrated that these...
Spin Hall effect of light has gained much attention due to enormous interesting phenomena and potential applications in functional photonic devices such as optical diode and optical topological insulator. For generic propagating waves such as plane wave, the spin angular momentum (SAM) is longitudinal (i.e., parallel to the wave vector k) and determined by the polarization sate. However, it is recently...
When using the Method of Moment (MoM) and MLFMA to calculate the scattered field of the perfect electric conductors (PEC), it is hard to calculate monostation RCS in case of the targets with electrically extreme large size. In this paper, an efficient numerical modeling method of monostation RCS for electrically extreme large PEC targets has been proposed based on the phase extracted basis functions...
A novel set of multilevel basis functions is proposed in this paper to improve the system matrix conditioning of the radiation problem for line-fed patch antenna. The proposed basis functions are formulated in a wavelet-like manner. As a result, they possess spatial resolutions and mutual orthogonality which are significant for a well conditioning of the system matrix. Compared with the conventional...
Cherenkov type sum-frequency and frequency doubling process, which has relatively high converscion efficiency with relaxed phase matching requirements, is a good way for high-order harmonic generation. Cascaded high order Cherenkov harmonic generation on the interface with second order nonlinear coefficient χ(2) from −1 to +1 (i.e., domain wall) has been research in the past. The high-order harmonic...
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