Results 11 to 20 of about 34,233 (259)
Multi-objective optimization of earth cooperative observation hybrid satellite constellation
Xibei Gongye Daxue Xuebao, 2021 As the demand for comprehensiveness, accuracy, and data fast return of satellite remote sensing information grows, a hybrid constellation with permanent inter-satellite link becomes an inevitable choice for earth cooperative observation.
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Design of Mega-Constellations for Global Uniform Coverage with Inter-Satellite Links
Aerospace, 2022 Constellation configuration design is a prerequisite and critical step in the construction of a mega-constellation system in low Earth orbit. However, the huge number of satellites and the intricate changes in relative positions among them make the ...
Lu Jia +3 more
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Spatial and Temporal Sampling Properties of a Large GNSS-R Satellite Constellation
Remote Sensing, 2023 Using large constellations of smallsats, mission designers can improve sampling density and coverage. We develop performance metrics that characterize key sampling properties for applications in numerical weather prediction and optimize orbit design ...
Jack Winkelried +2 more
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Design and Simulation of Stellar Occultation Infrared Band Constellation
Remote Sensing, 2022 This study provides an in-depth analysis of the characteristics of stellar occultation events. Using 10 target star sources, the influence of orbital elements on the number, duration, and distribution of stellar occultation events was simulated and ...
Qinglin Zhu +3 more
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Optimization of satellite resource scheduling under regional target coverage conditions
Open Astronomy, 2022 This study presented a mathematical description of an arbitrary shape area, and after analyzing the characteristics of the near-polar orbital co-ground trajectory constellation that satisfies the revisit interval constraint, an optimization model of the ...
Liu Kaixi +5 more
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Unitary Space-Time Modulation Based on Coherent Codes
Sensors, 2022 This paper analyzes the relationship between pilot symbol-assisted modulation (PSAM) and unitary space-time modulation (USTM). In particular, we present a map that transforms any PSAM into a USTM and vice versa.
Daniel Calabuig
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On the performance of improved quadrature spatial modulation
ETRI Journal, 2020 Quadrature spatial modulation (QSM) utilizes the in‐phase and quadrature spatial dimensions to transmit the real and imaginary parts of a single signal symbol, respectively.
Tasnim Holoubi +3 more
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Remote Sensing, 2022 The Gravity Recovery and Climate Experiment (GRACE) and GRACE Follow-On (GRACE-FO) provided twenty years of data on Earth’s time-varying gravity field.
Carlos M. A. Deccia +2 more
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NGSO Constellation Design for Global Connectivity
CoRR, 2022 Book chapter submitted to IET Non-Geostationary Satellite Communications ...
Israel Leyva-Mayorga +6 more
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IEEE Access, 2017 Physical-layer network coding holds the great potential of improving the power efficiency and the spectral efficiency for the two-stage transmission scheme. The first stage is the multiple access stage, where two source nodes (SN1 and SN2) simultaneously
Zhijiang Yu +4 more
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