Results 41 to 50 of about 13,719,025 (270)
IEEE Access, 2020 Question understanding is an extremely important part of the question and answer (Q&A) system, which is the basis of subsequent information retrieval and answer extraction.
Jiaxing Song +4 more
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Modeling and Analysis of Near-Field ISAC [PDF]
IEEE Journal on Selected Topics in Signal Processing, 2023 As technologies envisioned for next-generation wireless networks significantly extend the near-field region, it is of interest to reevaluate integrated sensing and communications (ISAC) with an appropriate channel model to account for the effects ...
Boqun Zhao +4 more
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Near-Field Sparse Channel Representation and Estimation in 6G Wireless Communications [PDF]
IEEE Transactions on Communications, 2022 The employment of extremely large antenna arrays and high-frequency signaling makes future 6G wireless communications likely to operate in the near-field region. In this case, the spherical wave assumption which takes into account both the user angle and
Xing Zhang +2 more
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Codebook design and beam training for extremely large-scale RIS: Far-field or near-field? [PDF]
China Communications, 2021 Reconfigurable intelligent surface (RIS) is more likely to develop into extremely large-scale RIS (XL-RIS) to efficiently boost the system capacity for future 6G communications. Beam training is an effective way to acquire channel state information (CSI)
Xiuhong Wei +4 more
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Principles of Planar Near-Field Antenna Measurements
, 2023 This single volume provides a comprehensive introduction and explanation of both the theory and practice of 'Planar Near-Field Antenna Measurement' from its basic postulates and assumptions, to the intricacies of its deployment in complex and demanding ...
S. Gregson, J. McCormick, C. Parini
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A Primer on Near-Field Beamforming for Arrays and Reconfigurable Intelligent Surfaces [PDF]
Asilomar Conference on Signals, Systems and Computers, 2021 Wireless communication systems have almost exclusively operated in the far-field of antennas and antenna arrays, which is conventionally characterized by having propagation distances beyond the Fraunhofer distance.
Emil Björnson +2 more
semanticscholar +1 more source
Nanopatterning with Photonic Nanojets: Review and Perspectives in Biomedical Research
Micromachines, 2021 Nanostructured surfaces and devices offer astounding possibilities for biomedical research, including cellular and molecular biology, diagnostics, and therapeutics.
Salvatore Surdo +2 more
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IEEE Access, 2021 The paper presents a method to design beam-steering antennas using a pair of 3D printed perforated dielectric structures (PDSs) placed in the near-field region of a base antenna, which has a fixed beam. Detailed designs and quantitative comparison of two
Touseef Hayat +5 more
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Hierarchical Beam Training for Extremely Large-Scale MIMO: From Far-Field to Near-Field [PDF]
IEEE Transactions on Communications, 2022 Extremely large-scale MIMO (XL-MIMO) is a promising technique for future 6G communications. The sharp increase in the number of antennas results in a transition of electromagnetic propagation from the far-field to the near-field.
Yu Lu, Linglong Dai
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Non-Uniform sampling in near field measurement: Experimental results [PDF]
, 2021 In this paper, the problem of sampling the field radiated by a planar source observed over a finite planar aperture located in the near-field is addressed. In particular, the paper is devoted to assess the performance of the sampling strategy proposed in
Giovanni, Leone +3 more
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