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Showing 1 to 20 of 24 for “"frequency-selective surface"”.
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Frequency selective surface (FSS) for cellular signals shelding
This thesis proposes a frequency selective surface (FSS) for interference control causes by the proliferation of mobile devices. FSS is a periodic structure etched on a dielectric substrate which acts as a spatial filter. The proposed FSS is designed as a band-stop filter to attenuate the cellular …
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Frequency selective surface-based sensing: Theory and applications
"Frequency selective surfaces (FSS) are periodic arrays of resonant elements with a specific (resonant) reflection/transmission response when illuminated by electromagnetic energy. FSSs have been utilized for different applications such as spatial filters, reflectors, lenses, radomes, and more …
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Active limiting frequency selective surface at X-band
… amount of power that the limiter must handle. A frequency selective surface with integrated limiter protection is proposed to mitigate this issue by moving the limiting function before the antenna, and this type of receiver protection has had minimal investigation in the existing literature. A …
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Techniques for analyzing planar, periodic, frequency selective surface systems
… for single-layer, infinite, planar, periodic frequency selective surfaces (FSS) are thoroughly reviewed. Particular emphasis is placed on practical procedures for implementing the analysis for the case of subdomain basis functions. In this presentation, the focus is placed on concepts which …
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Archimedean spiral antenna embedded with frequency selective surface for wideband applications
… frequencies. In order to improve the patterns, frequency selective structure is proposed to embed in the cavity of the spiral antenna. The optimized frequency selective surface improves the radiation pattern while maintaining the other parameters such as the gain, bandwidth and axial ratio. All …
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Measuring and filtering microwave radiations using frequency selective surface through energy saving glass
… Energy Saving Glass (ESG), in conjunction with Frequency Selective (FSS) surfaces through which useful signals can be filtered. In the investigation, radiation power density levels arising from the three common microwave sources (radio base stations, mobile phones, and microwave ovens) were …
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Synthesis Technique of Thickness-Customizable Multilayered Frequency Selective Surface for Plasma-Based Electromagnetic Structures
… high-order (N ≥ 2) bandpass frequency selective surface (FSS) and its application in realizing versatile multi-layered FSS and absorbers. Admittance inverters layers are used to synthesize the transfer response of the filter given desired characteristics such as filter type, …
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Terahertz metamaterials for sensing and detection
… on the polarization insensitive nature of the frequency selective surface elements. A mechanism for this property was proposed along with an equivalent circuit model that can describe and predict the resonant behavior. The perfect absorber were based on a unit cell structure with four-fold …
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Millimeter Wave Radar Object Detection Through Frequency Selective Surfaces
… performance is to enhance object visibility. Frequency selective reflectors can increase object visibility. This work examines the performance of a mmWave 77 GHz radar system developed by Texas Instruments in conjunction with frequency selective surfaces. Two bandpass frequency selective …
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Development And Characterization Of Beamforming Antenna Systems
… antenna system consisting of a single source and frequency selective surface (FSS) is proposed (chapter 2) and investigated. Since the FPC antenna system removes complicated feedline mechanism in array antenna system, it gains high interest to provide higher directivity/gain. Different FSS unit …
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An Investigation of Dual-Band Fabry-Pérot Resonant Cavity Antennas
… Fabry-Pérot resonant cavity antenna that uses a frequency selective surface (FSS) patch layer over a ground plane to form a composite artificial ground plane that replaces the single metal ground plane of the conventional structure. The structure thus consists of an upper cavity region (between …
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Fabricating Multifunctional Composites via Transfer of Printed Electronics Using Additively Manufactured Sacrificial Tooling
… processes for creating these structures through selective patterning of electrically conductive materials onto composites. Thus far, multifunctional composite performance has been limited by the conductivity of functional materials used, and the methods of integration have resulted in compromises …
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Obstacle avoidance robot applying fuzzy control system
… through them. These signals fall within the frequency band of 0.8GHz to 2.2GHz. In order to pass these signals through the coated glass, the use of aperture type frequency selective surface (FSS) has being proposed. In the present work, SnO2 thin film with FSS structure was fabricated using …
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Fabrication of frequency selective structure and evaluation of microwave transmission on energy saving glass
… through them. These signals fall within the frequency band of 0.8GHz to 2.2GHz. In order to pass these signals through the coated glass, the use of aperture type frequency selective surface (FSS) has being proposed. In the present work, SnO2 thin film with FSS structure was fabricated using …
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Fabrication of frequency selective structure and evaluation of microwave transmission on energy saving glass
… through them. These signals fall within the frequency band of 0.8GHz to 2.2GHz. In order to pass these signals through the coated glass, the use of aperture type frequency selective surface (FSS) has being proposed. In the present work, SnO2 thin film with FSS structure was fabricated using …
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Optimising the axial ratio bandwidth of resonant linear to circular polarisation converters
… and improving on published work. The operating frequency of these polarisation converters is centred around 10GHz.<br/><br/>Previously published work reported a 3dB axial ratio bandwidth of 2.4% for a cross-slot topology. The impact of the geometrical parameters on BW was investigated in this …
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Design a high gain UWB mimo uniplanar monopole antenna with FSS array for metallic object microwave imaging
… isolation. Moreover, the smallest uniplanar UWB frequency selective surface (FSS) unit cell size (0.095λx0.095λ) is miniaturized on the FR4 substrate. The simulations are compared with the equivalent circuit models of the proposed solutions, then validate with the measurement results. In the …
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Spectral Signature Modification By Application Of Infrared Frequency-selective Surfaces
… desirable to modify the spectral signature of a surface, particularly in the infrared (IR) region of the electromagnetic spectrum. To alter the surface signature in the IR, two methods are investigated: thin film application and antenna array application. The former approach is a common and …
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Integración de elementos activos en estructuras SIW
… novedosa, denominada SBFSS-SIW, Stop Band Frequency Selective Surface Substrate Integrated Waveguide, que permite sustituir la metalización superior e inferior de las estructuras SIW por superficies selectivas en frecuencia que operan en su banda de rechazo en el rango de funcionamiento de …
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Design of Microwave Front-End Narrowband Filter and Limiter Components
… SIW and HMSIW filters have 1.7 GHz center frequency and 0.2 GHz bandwidth. Simulation and measurements of the filters utilizing combline resonators prove the underlying principles.The second proposed device combines a traditional microstrip bent hairpin filter with encapsulated gas plasma …
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