The rapid development of Low Earth Orbit (LEO) mega constellations has significantly contributed to several aspects human scientific progress, such as communication, navigation, and remote sensing. However, unrestrained deployment also strained orbital resources increased spacecraft congestion in LEO, which seriously affects the safety in-orbit operations many space assets. For long-term sustai...

0163-6804/97/$10.00 © 1997 IEEE here are two well-established methods for providing wireless communication services: terrestrially based systems, as used in cellular and personal communications systems (PCS), and satellites. Each concept has its specific advantages and disadvantages. The high-altitude aeronautical platform (HAAP) technology, we will argue, would have many of the advantages of b...

A number of satellite communication systems have been proposed using geosynchronous (GEO) satellites, medium earth orbit (MEO) and low earth orbit (LEO) constellations operating in the Ka-band and above. The next generation broadband satellite systems will use fast packet switching with onboard processing to provide full two-way services to and from earth stations. New services gaining momentum...

The space-based GPS limb sounding, conventionally known as GPS Radio Occultation, is a remote sensing technique aiming at characterize the Earth atmosphere. The atmospheric profiling is done through the inversion of excess-phase measurements carried-out by a GPS receiver placed on-board a LEO (Low Earth Orbit) satellite. The GPS signal, observed when it emerges from the Earth limb, is refracted...

For a few years, multicarrier modulations have been proposed as valuable alternatives with respect to state-of-the-art single carrier ones due to their resilience against interference and channel distortion effects. In particular, many studies are arising about multicarrier-CDMA (MC-CDMA) techniques that provide improved robustness and flexibility with respect to single-carrier spread-spectrum ...

The advent of low earth orbit (LEO) commercial communication satellites provides an opportunity to dramatically reduce Telemetry, Tracking and Control (TT&C) costs of launch vehicles, Unpiloted Aerial Vehicles (UAVs), Research Balloons and spacecraft by reducing or eliminating ground infrastructure. Personnel from the Goddard Space Flight Center’s Wallops Flight Facility (GSFC\WFF) have success...

Over the last few years, new Global Navigation Satellite System (GNSS) applications have emerged that go far beyond the original objectives of GNSS which was providing position, velocity and timing (PVT) services for land, maritime, and air applications. Indeed, today, GNSS is used in Low Earth Orbit (LEO) for a wide range of applications such as real-time navigation, formation flying, precise ...

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...

The proliferation of low-earth orbit (LEO) satellites and the LEO satellite internet will be a game-changer for low-latency high-speed global internet. While this new generation in conjunction with fifth network (5G) sixth (6G) enabled emerging technologies, such as precision farming smart cities, it bring challenges, collision, limited lifespan, security concerns, brightness. This article disc...

The purpose of this paper is to perform the feasibility and performance evaluation of the High-altitude launch technique using high altitude atmospheric Properties to near earth orbits. The current propulsion transportation system from Earth to space has been deemed by many to be expensive, unreliable, and an unnecessarily dangerous means of travel to space. It is suggested in this paper to ana...