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A novel frequency splitter based on graphene plasmonic waveguide with composite periodic grating is proposed and demonstrated numerically. The graphene surface plasmon polarition (GSPP) modes with different eigenfrequencies are supported in the composite periodic grating waveguide due to the dispersion relation depended on the geometric structure. The light wave with single frequency can propagate...
A tri-band ultra-thin absorber using frequency selective surface (FSS) structure is proposed and experimentally measured in this paper. The simulated results show that three distinct absorption peaks centre at 3.42 GHz (S-band), 6.34 GHz (C-band) and 9.01 GHz (X-band) with absorptivities of 95.1%, 91.7% and 91.9%, respectively. Thus, the proposed structure has ultra-thin thickness of 0.8mm and miniaturized...
Spoof surface plasmon polaritons (SSPPs) are highly confined surface electromagnetic waves, which can be supported by subwavelength periodic metal structure. According to the theory of sinusoidally modulated reactance surface (SMRS), SSPPs could be transformed into directional leaky-wave radiation through wavenumber modulation. In this paper, we propose a method to suppress the sidelobe level of the...
Phase gradient metasurfaces (PGMs) are the two-dimensional metamaterial. It can manipulate the propagation direction, wave front and polarization of the reflected/transmitted waves with more freedom. In this paper, the phase gradient metasurfaces are used as the radomes to manipulate the direction of the main lobe or to improve the directivity of the patch antenna. Based on the transmissive polarization...
By using the scalar Kirchhoff-Huygens integral, analytic expressions were obtained for both axial and transverse intensity distributions of Bessel-Gaussian beam diffracted by a circular aperture. The effect of the output beam caused by different radius of the annular aperture also has been analyzed. The axial and transverse field intensity distribution analytical expression is deduced, it starting...
It has been demonstrated that photonic band gap can be realized in quasi-periodic photonic crystal. We design a two dimensional octagonal photonic quasicrystal composed of alumina cylinders. The photonic band gaps are theoretically examined by the Transfer Matrix Method (TMM) and Finite-Difference Time-Domain (FDTD) for transverse magnetic (TM) wave. A Y-shaped light splitter is designed and simulated...
Spectrally selective film with low emissivity has been attracting a great amount of research interest due to its extensive application in solar energy utilization, energy saving in buildings, etc‥ Photonic band gap (PBG) structures, having the potential ability to control the propagation of electromagnetic waves, provide great opportunities for realizing good compatibility of low emissivity and high...
Thanks to a very good velocity matching between the microwave signals and optical waves in polymeric materials and progress in the synthesis of high hyperpolarizability chromophores, electro-optic (EO) polymers offer a very attractive possibility to realize low cost photonic microwave components with a very wide bandwidth and a very low driving signal. Indeed, on one hand, the EO coefficient of EO...
Dirac cone dispensions in various periodic systems can lead to intriguing transport properties, such as Klein tunneling, Zitterbewegung, antilocalization, abnormal quantum Hall effect. From an effective medium perspective photonic crystals (PhCs) with the k = 0 Dirac-like point at the BZ center also can be regarded as the effective zero-refractive index materials with εeff = λeff = 0, which provide...
In this paper, a new ferrite-loaded waveguide isolator with frequency tunable is presented. Two pairs of ferrite cylinders are placed near sidewall in the waveguide. The magnetization of two pairs of ferrite rods are in opposite directions. One-way electromagnetic edge states has been demonstrated and observed experimentally in microwave regime. Such one-way propagation characteristics are usually...
Diode-pumped solid-state (DPSS) ultraviolet lasers have been proven to be effective for dicing various types of glass in various applications and mainly thin substrates for microelectronics. The main varieties of glass are transparent to wavelengths above 300–350 nm. However, GW/cm2 intensities can be produced by tightly focusing short pulses (nanosecond to femtosecond) that will enable nonlinear...
With the current state of affairs in the development of antennas in the wireless communication field, the need of compact multiband, multifunctional and cost effective antenna is increased. The study of reconfigurable antennas has made great progress in recent years. In this article, a multi-purpose reconfigurable antenna capable of dual-polarization and operating nine modes corresponding to nine...
A novel minimized microstrip planar antenna with pre-controllable resonant frequency and impedance matching is presented for microwave engineering applications. Double-sided planar structure is adopted to build the resonant loop of the antenna. The tuning of the impedance matching and the resonant frequency is studied, and the impedance matching and resonant frequency can be adjusted independently...
In this paper, we consider plasmonic nanoantennas with different elliptical metal rods embedded in a two-arm grating. Elliptical metal rods support dipolar localized plasmon resonance with a localized plasmon resonance frequency that is affected with different metal materials. We discuss the properties and parameters of different elliptical metal rods using finite-difference time-domain method in...
This article presents the scanning mechanism of push-broom satellite antenna working at 140 GHz. Such kind of antenna can be applied into many areas, such as imaging, ocean surveillance and astronomical observation. The feeds are placed at the rotary focus with a spacing of 1.72 cm between two adjacent feeds, and the center distance from the feed to the reflector surface is 14.48 cm. Meanwhile, the...
In this paper, Design of a reconfiguration frequency full metal case antenna with portable wireless terminal unit is presented in the Fig. 1. The prototype antenna in fabricated is used a copper sheet of 0.6mm thickness while occupies a volume of 13mm × 70mm × 0.6 mm, and suitable to be built-in housing of a mobile phone. A FR4 substrate with a thickness of 0.8 mm, relative permittivity of 4.4, and...
This paper presents characterization of Ultra-wide band diamond shaped patch monopole (DSM) antenna based on the singularity expansion method (SEM) model. The diamond shaped patch is designed to provide Ultra-wide bandwidth (UWB) of 12 GHz (3 to 15 GHz). To extract the complex poles in the SEM based model, Matrix Pencil method (MP) is used to provide the accurate complex poles and residues for the...
A new low profile ultra-wideband (UWB) monopole-type antenna is present in this paper. It is top-loaded with the metal plate to reduce its height. The feed point is located at the bottom of cylinder. Three shorting stubs on the edge and the central metallic circular truncated cone connected to the ground are used to further reduce the size of the antenna. The antenna has a 56% relative bandwidth covering...
In this paper, the artificial dielectric material with anisotropic permittivity is proposed to lower the resonant frequency of square patch antenna. The anisotropic artificial dielectric material is applied to replace the dielectric material usually used for implementing the conventional square patch antenna. Here, the conventional square patch antenna which is designed based on TM10 resonance mode...
In practical radar systems, amplitude and phase distortion exists in antenna channels, which has a bad effect on subsequent signal processing. So, waveform generator is needed to launch signals covering radar waveband to make a channel test. Ensuring accuracy and bandwidth of the waveform generator is a fundamental requirement. Accordingly, this paper proposed a full flow of wideband waveform generation,...
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