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High-efficacy global optimization of antenna structures by means of simplex-based predictors
Scientific Reports, 2023 Design of modern antenna systems has become highly dependent on computational tools, especially full-wave electromagnetic (EM) simulation models. EM analysis is capable of yielding accurate representation of antenna characteristics at the expense of ...
Slawomir Koziel +1 more
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Scientific Reports, 2023 Re-design of microwave passive components for the assumed operating frequencies or substrate parameters is an important yet a tedious process. It requires simultaneous tuning of relevant circuit variables, often over broad ranges thereof, to ensure ...
Slawomir Koziel +1 more
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IEEE Access, 2021 Modern communication systems of high data capacity incorporate circular polarization (CP) as the preferred antenna radiation field configuration. In many applications, integration of the system circuitry with antennas imposes size limitations on CP ...
Marzieh Mahrokh, Slawomir Koziel
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Scientific Reports, 2023 Modern microwave devices are designed to fulfill stringent requirements pertaining to electrical performance, which requires, among others, a meticulous tuning of their geometry parameters.
Slawomir Koziel, Tanveerul Haq
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IEEE Access, 2021 Multiple-input multiple-output (MIMO) antennas are considered to be the key components of fifth generation (5G) mobile communications. One of the challenges pertinent to the design of highly integrated MIMO structures is to minimize the mutual coupling ...
Muhammad Abdullah, Slawomir Koziel
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Secure Communication for Uplink Cellular Networks Assisted with Full-Duplex Device-to-Device User
Future Internet, 2020 In this paper, the secure communication based on the full-duplex (FD) device-to-device (D2D) in cellular networks is proposed. For the proposed scheme, the novel model is established, in which a D2D user is played as a relay operating in FD mode to ...
Xin Song, Lin Xia, Siyang Xu, Yue Wang
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Scientific Reports, 2022 Conceptual design of contemporary high-frequency structures is typically followed by a careful tuning of their parameters, predominantly the geometry ones. The process aims at improving the relevant performance figures, and may be quite expensive.
Slawomir Koziel +1 more
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Design optimization of baffle in heat exchanger for improving flow maldistribution and pressure drop
Nihon Kikai Gakkai ronbunshu, 2022 Heat exchangers (HEs) are used in process industries such as power plants and petroleum refineries. It is important to minimize flow maldistribution as well as pressure drop for high performance of HE. A baffle is often installed in the header part of HE
Kohei MIYAMOTO +4 more
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Energy Efficient Power Allocation for Downlink NOMA Heterogeneous Networks With Imperfect CSI
IEEE Access, 2019 Non-orthogonal multiple access (NOMA) is a promising emerging technology that can significantly improve the utilization of spectrum and system capacity in heterogeneous wireless networks.
Xin Song +4 more
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Joint Uplink and Downlink Resource Allocation for D2D Communications System
Future Internet, 2019 In cellular networks, device-to-device communications can increase the spectrum efficiency, but some conventional schemes only consider uplink or downlink resource allocation.
Xin Song +4 more
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