Results 71 to 80 of about 166,231 (222)
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
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
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
Orbital Elements Ephemerides and Interfaces Design of LEO Satellites [PDF]
Journal of Geodesy and Geoinformation Science, 2019 Low earth orbit satellites, with unique advantages, are prosperous types of navigation augmentation satellites for the GNSS satellites constellations. The broadcast ephemeris element needs to be designed as an important index of the augmented LEOs.
Shanchuan FANG,Lan DU,Yunpeng GAO,Peiyuan ZHOU,Zejun LIU
doaj +1 more source
Comprehensive Analyses of PPP-B2b Performance in China and Surrounding Areas
Remote Sensing, 2022 BeiDou Global Navigation Satellite System (BDS-3) provides a regional Precise Point Positioning (PPP) service, called PPP-B2b, for users in China and surrounding areas through B2b signal transmitted from its three geostationary earth orbit (GEO ...
Yan Liu, Cheng Yang, Mengni Zhang
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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
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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
Remote Sensing, 2021 On 31 July 2020, the Beidou global navigation satellite system (BDS-3) was officially announced as being commissioned. In addition to offering global positioning, navigation, and timing (PNT) services, BDS-3 also provides precise point positioning (PPP ...
Zhixi Nie +3 more
doaj +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
Design and Reception Method of Code Shift Keying Signals With Power‐of‐Two Phase Intervals
IET Radar, Sonar &Navigation, Volume 19, Issue 1, January/December 2025.A novel approach for the design and reception of CSK signals with a phase interval mapping of power‐of‐two chips is proposed. This method is capable of significantly reducing the demodulation complexity while mitigating the intersymbol interference. ABSTRACT Precise point positioning (PPP) technology has garnered extensive attention for its ability to ...
Nengjie Yu +4 more
wiley +1 more source