Results 31 to 40 of about 1,544 (147)
Representations of Time Coordinates in FITS
, 2014 In a series of three previous papers, formulation and specifics of the representation of World Coordinate Transformations in FITS data have been presented. This fourth paper deals with encoding time.
Allen, Steven L. +5 more
core +1 more source
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
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
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
Transit satellite system timing capabilities [PDF]
, 1978 Current time transfer capabilities of the Transit Satellite System are reviewed. Potential improvements in the changes in equipment and operational procedures using operational satellites are ...
Finsod, T. D.
core +1 more source
IEEE Access, 2023 BDS-3 was formally put into service on July 31, 2020, and now along with BDS-2 provides the positioning, navigation and timing services. In this contribution, different techniques of dual-frequency absolute positioning using the fully serviceable BDS-2+3 constellation are evaluated and compared to the positioning performance of GPS constellation.
Shengnan Liu, Shaolin Zhu, Jian Zhang
openaire +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
Engineering Reports, Volume 7, Issue 1, January 2025.ABSTRACT Due to the long transmission distance of the constellation network represented by the low‐orbit satellite system, the satellite‐to‐ground link is subject to large path loss and limited communication performance. This paper uses multi‐satellite and multi‐beam joint transmission technology to form a virtual multiplex network with ground multi ...
Yuyang Liu, Tong Shi, Hua Wang
wiley +1 more source
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 +2 more
wiley +1 more source
Application of GPS tracking techniques to orbit determination for TDRS [PDF]
In this paper, we evaluate two fundamentally different approaches to TDRS orbit determination utilizing Global Positioning System (GPS) technology and GPS-related techniques. In the first, a GPS flight receiver is deployed on the TDRSS spacecraft.
Haines, B. J. +3 more
core +1 more source