Results 21 to 30 of about 725 (134)

Izračun položaja GPS-satelita iz podatkov preciznih efimerid : GPS-orbit computation from precise ephemeris data [PDF]

Geodetski Vestnik, 2005
The article describes the theoretical point of view of the GPS precise ephemerides application that should be used in most precise GPS processing. Regarding broadcast, precise ephemerides allow us to achieve a much better accuracy of the final GPS ...
Bojan Stopar, Polona Pavlovčič Prešeren   +1 more
doaj  

Performance Assessment of Non-Integer-Hour Data Blocks in BDS Broadcast Ephemeris

IEEE Access
Due to system anomalies, BeiDou navigation satellite system (BDS) sometimes updates the broadcast ephemeris at non-integral hours. The gross errors contained in the non-integer-hour data blocks of broadcast ephemeris will lead to the signal-in-space (SIS)
Jingjing Wang, Chao Zhou
doaj   +1 more source

Low‐Complexity Hybrid Beamforming for LEO Satellites: Beam Update Rate Analysis and Advanced Adaptive Precoding

International Journal of Satellite Communications and Networking, EarlyView.
ABSTRACT Low Earth Orbit (LEO) satellite constellations offer unprecedented opportunities for global broadband connectivity but pose significant beamforming challenges due to rapid platform motion and stringent onboard hardware constraints. Fully digital architectures, while optimal in theory, remain impractical for satellite payloads, motivating ...
Mohammad Momani, Thomas Delamotte, Andreas Knopp   +2 more
wiley   +1 more source

Real-Time Precise Point Positioning Method Considering Broadcast Ephemeris Discontinuities

Navigation
With advancements in the broadcast ephemeris accuracy of global navigation satellite systems (GNSSs), precise point positioning based on broadcast ephemeris (BE-PPP) is gradually showing promising prospects.
Quanrun Cheng, Junping Chen, Yize Zhang, Chao Yu   +3 more
doaj   +1 more source

City of God and the Duty of Just Memory

Modern Theology, EarlyView.
Abstract In a recent essay, Richard Miller claims that Augustine presumes a duty to remember justly in his City of God. However, Miller's brief reference to a presumed duty of “just memory” does not fully explain how Augustine conceptualizes this duty or how it relates to his theological concerns.
Zachary J. Taylor
wiley   +1 more source

High‐Latitude GPS Position Error During Substorms

Space Weather, Volume 24, Issue 6, June 2026.
Abstract Substorms produce rapid fluctuations in Global Navigation Satellite System (GNSS) signals, leading to degraded positioning performance at high latitudes. This study investigates the correlation of auroral structures on Global Positioning System (GPS) Precise Point Positioning (PPP) error during three substorm events with different strengths ...
Weixuan Liao, Yukitoshi Nishimura, Waqar Younas, Wen Li, Keith M. Groves, Eric F. Donovan, Vassilis Angelopoulos   +6 more
wiley   +1 more source

Assuring the Legacy of the CoRoT Planets

EPJ Web of Conferences, 2015
For the long-lasting impact of CoRoT’s planet findings, precise knowledge of the times of their transits is of vital importance for any future observing campaigns.
Deeg H.J., Klagyivik P., Alonso R., Hoyer S.   +3 more
doaj   +1 more source

A rapid stability assessment of China's IGS sites after the Ms7. 0 Lushan earthquake

Geodesy and Geodynamics, 2013
A rapid and accurate assessment of the stability of surveying and mapping reference points is important for post – disaster rescue, disaster relief and reconstruction activities. Using Precise Point Positioning (PPP) technology, a rapid assessment of the
Meng Jie, Chen Yongxiang, Wan Xin, Zhang Yingli   +3 more
doaj   +1 more source

Analysis and Assessment of BDS-2 and BDS-3 Broadcast Ephemeris: Accuracy, the Datum of Broadcast Clocks and Its Impact on Single Point Positioning

Remote Sensing, 2020
For the global ordinary users, the broadcast ephemeris plays important roles in positioning, navigation and timing (PNT) services. With the construction of a new generation of the BeiDou navigation satellite system (BDS), the development of BDS has ...
Guoqiang Jiao, Shuli Song, Yangyang Liu, Ke Su, Na Cheng, Shengli Wang   +5 more
doaj   +1 more source

Solar Energetic Particle Prediction in the Inner Heliosphere Using Deep Learning and PSP/IS⊙IS Data

Journal of Geophysical Research: Machine Learning and Computation, Volume 3, Issue 3, June 2026.
Abstract Solar events, such as coronal mass ejections and solar flares, accelerate large numbers of energetic charged particles, producing solar energetic particle (SEP) events that can harm astronauts, damage satellites, and potentially damage infrastructure on Earth.
Tate Hutchins, Spiridon Kasapis, Hameedullah Farooki, Manuel E. Cuesta, Lengying Khoo, Sungmin Pak, Robert Czarnota, Jamie Rankin, Jamey Szalay, Zigong Xu, Georgios Livadiotis, Nikolaos Sarlis, David McComas   +12 more
wiley   +1 more source