The increasing number of launched satellites per year calls for solutions to keep free operational space for telecommunication systems in GEO, as well as to avoid the endangering of space systems in LEO and of the public living on Earth. Malfunctions of satellite sub-systems like solar generators, control systems, or thrusters cannot be avoided. Therefore, on-orbit servicing (OOS) will be a man...

In a Low Earth Orbit (LEO) satellite mobile multimedia system, the multiple access scheme should be capable of supporting the necessary features that would facilitate the provision of multimedia services. Wideband Code Division Multiple Access (WCDMA) is an attractive multiple access scheme for mobile multimedia communications based on LEO satellites. In this paper, the performance of WCDMA sys...

Global Navigation Satellite System (GNSS) observations from worldwide ground-based stations have been extensively used in traveling ionospheric disturbance (TID) detections. However, these primarily cover land area, thus causing a challenging problem of interpreting the global propagating characteristics large-scale TIDs (LSTIDs), especially over ocean area. Meanwhile, Total Electron Content (T...

Ubiquitous connection to modern vehicles is mandatory support diverse intelligent functions, including autonomous driving, telediagnosis, infotainment services, and others. Since the deployment of cellular access points still scarce in rural areas, low earth orbit (LEO) constellation-based communication believed provide a realistic alternative. However, due long propagation delay limited satell...

Fragmentation clouds from explosions or collision of payloads and rocket bodies in space pose a threat to objects Earth orbit. Most the fragments are too small be tracked can only accounted for statistically. Here, framework fully statistical treatment fragmentation cloud, its evolution ramifications, without need simplifying assumptions, is presented. The cloud modeled as an uncertainty around...

Several strategies have been proposed for routing in the Low Earth Orbit (LEO) satellite networks. The multi-layered routing approaches are envisioned as promising because they use Middle Earth Orbit (MEO) satellite to extend the LEO satellite network’s communication capabilities. The previously proposed multi-layered routing approaches, however, still assume that the satellites in the same lay...

Recent technological advances have accelerated a renaissance in usage of non-geostationary (non-GSO) communication satellites in provision of various services domestically and globally. Early ventures into communication satellites have used satellites in low Earth orbits. The main reasons for this mode of operation were that the booster technology was not available to lift satellites into a hig...

For real-time precise orbit determination (POD) of low earth (LEO) satellites, high-accuracy global navigation satellite system (GNSS) and clock products are necessary in real time. Recently, the Japanese multi-GNSS advanced demonstration analysis point positioning (PPP) service new generation Australian/New Zealand satellite-based augmentation (SBAS)-aided PPP provide free GNSS that directly b...

Satellite constellations ooer interesting perspectives for Internet traac routing, since they beneet from a worldwide coverage and do not have the main drawback of geosynchronous satellites : propagation delay. However, because of their low altitude, LEO satellites are in constant motion and exhibit speciic issues for routing. This article presents a general architecture applicable to the integ...

This paper presents an adaptive forward error correction (AFEC) protocol that provides a reliable communication service for real-time trafflc over low-earth orbit (LEO) satellite networks. In time-varying wireless links, such as LEO satellite networks, a reliable channel estimation scheme with an appropriate code selection technique is essential for adaptive error-control systems. This paper pr...