Results 101 to 110 of about 135,824 (242)

Physical layer security in satellite communication: State‐of‐the‐art and open problems

IET Communications, Volume 19, Issue 1, January/December 2025.
This paper first classifies contemporary satellite communication networks into five domains and then analyse the use of PLS in each domain; these domains are hybrid satellite‐terrestrial networks, satellite‐based IoT, navigation satellite systems, FSO‐based satellites, and inter‐satellite communications.
Nora Abdelsalam, Saif Al‐Kuwari, Aiman Erbad   +2 more
wiley   +1 more source

A new and improved ephemeris for the hot subdwarf eclipsing binary SDSS J082053.53+000843.4 [PDF]

arXiv, 2015
SDSS J082053.53+000843.4 belongs to the HW Vir family of short period binary systems and was first identified by Geier in 2011. Whilst three subsequent papers have focused on the morphology of this system, little has been published on the system period and its constancy.
arxiv  

Precise CCD positions of Triton in 2014-2016 using the newest Gaia DR1 star catalogue [PDF]

, 2017
755 new CCD observations during the years 2014-2016 have been reduced to derive the precise positions of Triton, the first satellite of Neptune. The observations were made by the 1 m telescope at Yunnan Observatory over fifteen nights. The positions of Triton are measured with respect to the stars in Gaia DR1 star catalogue. The theoretical position of
arxiv   +1 more source

An Alternative Approach for Pseudorange Variance Estimation Under Scintillation Environments Using Markov‐Rao‐Blackwellized Particle Filtering

IET Radar, Sonar &Navigation, Volume 19, Issue 1, January/December 2025.
This study presents a Markov‐Rao‐Blackwellized Particle Filter to mitigate ionospheric scintillation effects on GNSS positioning. It achieves sub‐2‐metre errors in strong scintillation scenarios, outperforming traditional methods. ABSTRACT Ionospheric scintillations, arising from variations in phase/amplitude of radio signals traversing the ionosphere,
Paulo Silva, Marcelo G. S. Bruno, Victor di Santis, Alison Moraes, Jonas Sousasantos, Leonardo Marini‐Pereira   +5 more
wiley   +1 more source

Accurate and Rapid Broadcast Ephemerides for Beidou-Maneuvered Satellites

Remote Sensing, 2019
The geostationary earth orbit (GEO) and inclined geosynchronous orbit (IGSO) satellites of the Beidou navigation satellite system are maneuvered frequently. The broadcast ephemeris can be interrupted for several hours after the maneuver.
Jing Qiao, Wu Chen, Shengyue Ji, Duojie Weng   +3 more
doaj   +1 more source

Detection of a transit by the planetary companion of HD 80606

, 2009
We report the detection of a transit egress by the ~ 3.9-Jupiter-mass planet HD 80606b, an object in a highly-eccentric orbit (e ~ 0.93) about its parent star of approximately solar type. The astrophysical reality of the signal of variability in HD 80606
Agol, Barbieri, Claret, David M. Kipping, Dommanget, Ford, Garcia-Melendo, Hog, Holman, Ingo P. Waldmann, Kipping, Kipping, Laughlin, Mamajek, Mamajek, Mandel, Moutou, Naef, Press, Saffe, Stephen J. Fossey, Stetson, Swain, Tinetti, Winn, Winn, Wu, Zeng   +27 more
core   +1 more source

A X‐Ray Pulsar/Inter‐Satellite Ranging/Landmark Integrated Navigation Method for Deep Space Exploration

IET Radar, Sonar &Navigation, Volume 19, Issue 1, January/December 2025.
This paper proposes a Mars probe navigation method that integrates three navigation techniques: x‐ray pulsar, inter‐satellite ranging and landmark‐based navigation. By using the difference in pulse arrival times (TDOA) observed by the probe and the auxiliary satellite, the method eliminates constant systematic errors, improves state estimation and ...
Shuting Wang, Yuqi Guo, Xiao Chen, Jun Xu, Xin Ma   +4 more
wiley   +1 more source

LEO Onboard Real-Time Orbit Determination Using GPS/BDS Data with an Optimal Stochastic Model

Remote Sensing, 2020
The advancements of Earth observations, remote sensing, communications and navigation augmentation based on low Earth orbit (LEO) platforms present strong requirements for accurate, real-time and autonomous navigation of LEO satellites.
Xuewen Gong, Jizhang Sang, Fuhong Wang, Xingxing Li   +3 more
doaj   +1 more source

Phase 1 Navstar/GPS ephemeris and space vehicle clock performance summary [PDF]

The Navstar/Global Positioning System (GPS) is considered. The issue of control segment accuracy in predicting space vehicle (SV) clock and ephemeris states for broadcast to the user community is addressed.
Bierman, A. B.
core   +1 more source

PPP Solution‐Based Model of Absolute Vertical Movements of the Earth's Crust in Poland With Consideration of Geological, Tectonic, Hydrological and Mineral Information

Earth and Space Science, Volume 11, Issue 12, December 2024.
Abstract This study aims to develop an absolute model of contemporary Vertical Crustal Movements (VCM) and Vertical Land Movements (VLM) in an area of Poland based on GNSS solutions. Velocities at permanent stations were subjected to geological, tectonic, hydrological and mineral information analyses.
B. Naumowicz, K. Kowalczyk, R. Pelc‐Mieczkowska   +2 more
wiley   +1 more source