Global ETD Search
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Showing 1 to 6 of 6 for “"superdirectivity"”.
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Superdirectivity and the Application of Complementary Split Ring Resonators in Directivity Enhancement of Millimeter-Wave Antennas
… by this limitation, this work investigates superdirectivity for millimeter wave antenna designs. Superdirectivity happens when a radiating body exceeds its maximum theoretical directivity limit. Based on a comprehensive literature review, a recent redirection away from reactive loading and …
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The Impact of Antenna and RF System Characteristics on MIMO System Capacity
… channel of interest, it is surprising that array superdirectivity has yet to be observed in theoretical solutions to the problem. When formulating system capacity using a radiated power constraint, the capacity is shown to be overestimated due to superdirectivity. Since superdirectivity provides …
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MIMO Communication Capacity: Antenna Coupling and Precoding for Incoherent Detection
… Specifically, it examines the impact of superdirectivity for compact antenna arrays, the effect of antenna mutual coupling, and MIMO performance of multi-mode optical fiber with non-linear detection. Superdirectivity can lead to abnormally large capacity bounds in a MIMO communication …
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Sub-Diffraction Imaging using Superoscillatory Electromagnetic Waves
… a relationship between superoscillation and superdirectivity, a design procedure is formulated whereby antenna array theory is leveraged to design 1D and 2D superoscillatory waves. These waves are then physically synthesized or implemented as a filter in focusing and imaging systems at …
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Microwave Properties of Helical Resonators
… behaviour and the potential for achieving superdirectivity in coupled systems. Further extending this concept to infinite chains of helical elements, the study further shows that specific geometric configurations can result in near-zero group velocity, paving the way for novel wave …
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Design, analysis, application and experimental assessment of algorithms for the synthesis of maximally sparse, planar, non-superdirective and steerable arrays
… at distances below half-wavelength: the non-superdirectivity. Moreover, an interesting result will be derived and discussed: the trend of the reduction of the number of elements Versus the (maximum) antenna size is decreasing as the latter increases. Afterwards the discussion will be focused …