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An all-dielectric multilayer polarization converter based on form birefringence is analytically synthesized and designed at microwave frequencies. Form birefringence enables to independently control the transmission characteristics of the parallel and perpendicular components of a linearly polarized incident plane-wave, thus achieving polarization conversion. The performance of the converter is demonstrated...
Metallic nano-particles support localized surface plasmon resonances (LSPRs) associated with the interaction of free electrons on the metal surface and incoming light. LSPRs can enhance the electric field by several orders of magnitude while confining it to sub-wavelength regions. Recently, we showed that arrays of closely spaced nano-rings can also enhance and localize the magnetic field. Our results...
A novel all dielectric conformal antenna is analysed and designed using a coordinate transformation of the spherical Luneburg lens. The non-directive beam radiated by a single source is converted to a highly-directive beam in a wide frequency range with low side-lobe level owing to the calculated permittivity map of the transformed lens. The electromagnetic behaviour is examined using a 2-D finite-difference...
Tunable THz metamaterials have been designed and modeled. Three different structures are under investigations: array of U-shaped planar resonators and metal-dielectric-metal patch array with voltage controlled cantilevers and dielectric resonators based structure with disturbed Mie resonance. All structures exhibit efficient control of electromagnetic response. An optical superlens based on a coupled...
Recently, we suggested the idea of an optical superlens based on a coupled pair of 2D arrays of plasmonic nano-ellipsoids. This superlens was capable of restoring sub-wavelength features of an object for s- and p-polarisation of light. In this contribution, a fast and rigorous simulation tool is employed for the imaging performance of a cluster of coupled sub-wavelength resonators. Simulations show...
We describe the ongoing deployment of a wireless network system for monitoring aquaculture applications and managing a lake resource in one of the Seven Lakes in San Pablo, Laguna, Philippines. Field servers are deployed to measure water quality parameters such as dissolved oxygen and temperature. In addition, a novel floating platform field server is developed to gather data in the middle parts of...
This paper presents an accurate analysis technique for designing broadband high-gain 2-D Fabry-Perot Leaky-Wave Antennas (LWA) consisting of two periodic metallodielectric arrays over a ground plane. Full-wave method of moments (MoM) is employed for the estimation of the near fields upon plane wave illumination and reciprocity is applied for the extraction of the radiation and directivity patterns...
The effect of a dielectric body on the performance of a near-field antenna-array probe designed for sub-wavelength focusing is presented by computing the fields inside the dielectric using CST Microwave Studio 2010. Simulations were conducted considering an array composed of a centrally fed monopole surrounded by parasitic secondary monopoles (placed less than half a wavelength away) and a dielectric...
In this paper, the authors present a full wave periodic analysis of Fabry-Perot resonant cavity leaky-wave antennas(LWA). The effect of the geometrical features on the antenna's performance is studied and design guidelines are derived for increased bandwidth performance.
Nowadays, the presence of distributed generation (DG) is steadily growing. This growth can produce significant effects on the costs incurred by distribution system operators (DSOs). This impact can be particularly negative if DG keeps playing a passive role, not reacting to network conditions. However, the implementation of advanced response options or active network management (ANM) may mitigate...
This paper presents a fast and accurate analysis and synthesis technique for highly directive 2-D Fabry-Perot leaky-wave antennas (LWA) consisting of two periodic metallo-dielectric arrays over a ground plane. Full-wave method of moments (MoM) together with reciprocity is employed for the estimation of the near fields upon plane wave illumination and the radiation patterns of the LWA. Two antenna...
A new simple and rigorous analysis technique is presented to derive the complex dispersion characteristics of periodic 2-D Fabry-Pérot Leaky-Wave Antennas (LWA). In order to illustrate the basics of the method an example involving a 2-D periodic array acting as a partially reflecting surface (PRS) situated at half-wavelength distance from a ground plane is utilised. The analysis procedure is based...
We present simple and accurate analysis techniques to simulate and design high-gain Fabry-Perot resonant leaky-wave antennas (LWA). To control the radiation properties of these antennas, two metallodielectric periodic structures are used, one acting as a partially reflective surface (PRS) and a second acting as a high impedance surface (HIS). Full-wave method of moments (MoM) is employed for the estimation...
The analysis of sub-wavelength profile high-gain planar antennas employing two periodic surfaces (AMC and PRS) has been presented using periodic spectral-domain MoM. Three different cavity antenna designs consisting of a grounded 2-D infinite array of metal patches and a superimposed infinite PRS array have been proposed in order to validate the technique. The thickness of the cavity for the three...
The support of electricity generation from renewable energy sources (RES) and combined heat and power (CHP) has led to increasing penetration levels of distributed generation (DG). Nevertheless, Large-scale connection of DG faces numerous regulatory, economic, social and technological challenges. Distribution networks were not originally designed to accommodate generation. Hence, distribution system...
The pole and zero matching method has been applied for the dispersion analysis of waveguides loaded with metamaterial surfaces. Very good agreement with commercial software packages has been observed. This allows to produce a synthesis procedure, where the admittance characteristics of the metasurface are designed to meet the dispersion requirements. A matched finite structure has been designed and...
Periodic metallic arrays printed on dielectric slabs have attracted a lot of interest in the past few decades due to their filtering properties on incident plane waves and their wide number of applications as radomes, polarizers and frequency scanning devices for microwave and optical frequencies. More recently other properties of these metallic arrays have been demonstrated such as certain bands...
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