Results 61 to 70 of about 3,334 (205)
Space Weather, Volume 23, Issue 7, July 2025.Abstract Ionospheric scintillation caused by space weather impacts the accuracy and availability of GNSS services and is considered a natural hazard for aviation and other GNSS users. Increased solar activity in 2021–2023, attributed to the ascending phase of the 25th solar cycle, caused an amplification of ionospheric disturbances including the ...
L. Nikitina +4 more
wiley +1 more source
Izračun položaja GPS-satelita iz podatkov oddanih efemerid : GPS-Orbit Computation from Broadcast Ephemeris Data [PDF]
Geodetski Vestnik, 2004 The article describes the theoretical point of view of the GPS-broadcast ephemerides application. Beside the raw GPS observations, any kind of GPS ephemerides represents indispensable data in the GPS processing engine.
Bojan Stopar +1 more
doaj
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 +3 more
doaj +1 more source
Phoenix-XNS - A Miniature Real-Time Navigation System for LEO Satellites [PDF]
, 2006 The paper describes the development of a miniature GPS receiver with integrated real-time navigation system for orbit determination of satellites in low Earth orbit (LEO).
Gill, Eberhard, Montenbruck, Oliver
core
The Future of Time: UTC and the Leap Second
, 2011 Before atomic timekeeping, clocks were set to the skies. But starting in 1972, radio signals began broadcasting atomic seconds and leap seconds have occasionally been added to that stream of atomic seconds to keep the signals synchronized with the actual
Allen, Steve +4 more
core +1 more source
Laser Terminals on CubeSats: Developments for Telecommunications and Quantum Links
International Journal of Satellite Communications and Networking, Volume 43, Issue 3, Page 133-146, May/June 2025.ABSTRACT Satellite‐based laser communication is an emerging technology that is finding its way from research to industry. Compared to radio frequency (RF) systems, it has a more efficient size, weight, and power budget and, furthermore, is license free.
Christian Roubal +8 more
wiley +1 more source
Performance Analysis of L2 and L5 CNAV Broadcast Ephemeris for Orbit Calculation
Navigation, 2015 Ephemeris error is a limiting factor in GPS position accuracy. The newly introduced GPS Civil Navigation (CNAV) broadcast message, an upgraded version of the legacy NAV message, is designed to provide users with more precise satellite orbit and timing parameters. A CNAV broadcast test was conducted in 2013 on the L2C and L5 bands. Since April 2014, pre-
Yu Morton +3 more
openaire +2 more sources
An Ionospheric Disturbed Index Based on ROTI
Space Weather, Volume 23, Issue 6, June 2025.Abstract The ionosphere has significant impacts on wireless communication, satellite navigation, and space weather. Based on hundreds of global GNSS observation stations, we calculate the rate of TEC index (ROTI). Through the analysis of ROTI, we establish a global ionospheric disturbed index (IDI) to directly characterize ionospheric disturbances ...
Cheng Wang, Xiaoxue Min, Hong Hu
wiley +1 more source
Space Weather, Volume 23, Issue 2, February 2025.Abstract With the onset of solar activities of the 25th solar cycle, ionospheric perturbations have become increasingly frequent, posing significant challenges to various applications of Global Navigation Satellite Systems (GNSS). The Rate of Total Electron Content (TEC) Index (Rate of TEC Index (ROTI)), commonly derived from GNSS data sampled at 30‐s ...
Zhouyu Zhang +6 more
wiley +1 more source
A fast cold-start method of GPS receiver based on satellite orbit prediction
MATEC Web of Conferences, 2018 Time to first fix (TTFF) is one of the crucial indicators to evaluate the performance of a GPS receiver. In this paper, an orbit prediction algorithm to reduce the TTFF of GPS receivers without a network connection is presented.
Yang Ruihong +3 more
doaj +1 more source