Results 21 to 30 of about 771 (159)
Dynamic Downlink Interference Management in LEO Satellite Networks Without Direct Communications
IEEE Access, 2023 We investigate effective interference management for Low Earth Orbit (LEO) satellite networks that provide downlink services to ground users and share the same frequency spectrum range.
Jihyeon Yun +5 more
doaj +1 more source
A Hybrid Genetic Algorithm for Satellite Image Downlink Scheduling Problem
Discrete Dynamics in Nature and Society, 2018 The satellite image downlink scheduling problem (SIDSP) is included in satellite mission planning as an important part. A customer demand is finished only if the corresponding images are eventually downloaded.
Bingyu Song +4 more
doaj +1 more source
Photonics, 2022 By analyzing the effect of the degree of polarization (DoP) of the partially coherent Gaussian Schell-model (GSM) beam on a heterodyne system of an uplink path and a downlink path, we developed an innovative and noteworthy theory according to which σsy ...
Zhenkun Tan +4 more
doaj +1 more source
Results in Physics, 2021 As many related experimental and theoretical results are identified, scholars have found that the anisotropy of turbulence cells is indispensable in the atmospheric turbulence. In this paper, based on a new anisotropic non-Kolmogorov turbulence spectrum for the satellite links that is applicable to both vertical and slant links, the probability density
openaire +2 more sources
Cooperative Reception of Multiple Satellite Downlinks
Sensors, 2022 Popular small satellites host individual sensors or sensor networks in space but require ground stations with directional antennas on rotators to download sensors’ data.
Haidar N. Al-Anbagi, Ivo Vertat
doaj +1 more source
PhotonicsSecurity is paramount in space–air–ground integrated networks (SAGINs) due to their inherent openness and the broadcast characteristics of wireless transmission. In this paper, we propose a secure downlink transmission scheme with NOMA-based mixed FSO/RF
Yu Li +4 more
doaj +1 more source
Survey on AI‐Enabled Computer Vision Technologies and Applications for Space Robotic Missions
Journal of Field Robotics, EarlyView.ABSTRACT This survey provides a comprehensive overview of recent advancements and challenges in Artificial Intelligence (AI)‐enabled computer vision (CV) techniques for space robotic missions, spanning critical phases such as Entry, Descent, and Landing (EDL), orbital operations, and planetary surface exploration.
Maciej Quoos +6 more
wiley +1 more source
Performance Analysis of DPSK Optical Communication for LEO-to-Ground Relay Link Via a GEO Satellite
Journal of Astronomy and Space Sciences, 2020 Satellite optical communication has gained significant attention owing to its many quality features (e.g., a larger bandwidth, license free spectrum, higher data rate, and better security) compared to satellite microwave communication.
Hyung-Chul Lim +5 more
doaj +1 more source
Location‐Assisted Graph‐Based User Scheduling in Multi‐User MIMO LEO NTN Systems
International Journal of Satellite Communications and Networking, EarlyView.ABSTRACT This paper addresses user clustering and scheduling for multi‐user MIMO low Earth orbit nonterrestrial network systems in full frequency reuse. Since the number of on‐ground user terminals is usually much higher than the number of on‐board LEO satellite antennas, user scheduling becomes a fundamental task.
Bilal Ahmad +4 more
wiley +1 more source