Use of the differential carrier phase measurements of the Global Positioning System (GPS) can achieve centimetre-level accuracy thus it can be applied to the relative positioning in formation flying missions. This paper describes the development of a spaceborne GPS receiver upon the UNSW’s Namuru GPS receiver, which is built on the field of field programmable gate array (FGPA). Operating a GPS ...

Considering the problem of GNSS service interruption caused by insufficient number available satellites in complex environments, Low Earth Orbit (LEO) can supplement effectively. To eliminate unknown satellite clock error and atmospheric delay with spatial correlation LEO observations, a Differential-Low opportunistically enhancing (D-LoeGNSS) navigation framework is proposed. Firstly, because ...

In space, radio frequencies (RFs) are usually used for long-distance linkage. However, recent progress in optics and laser technologies, especially in fiber optics, is ushering in an era of inter-orbit communications using laser beams. Both RFs and optical waves are electromagnetic waves, but optical waves offer many advantages in space, including reduced mass, power, and volume of equipment, h...

Resilience, the ability of a system to withstand disruptions and quickly return normal state, is essential for low-Earth-orbit satellite communication (LEO-SCS), as its large number satellites, may encounter various disturbances. As developing with asymmetrical insufficient data, it both aleatory epistemic uncertainties, which renders existing resilience measures inapplicable. This paper utiliz...

With the rise of a new generation low Earth orbit (LEO) satellite constellations and advancement 6G network, satellite–terrestrial integrated Internet Things (IoT) in future will achieve global coverage through integration LEO constellation, extend computing to edge network deployment services constellation so as meet demand mass connection latency data processing. The be an cloud combining com...

The first five years of operation the Deep Space Climate Observatory (DSCOVR) Earth Polychromatic Imaging Camera (EPIC) at Lagrange one point have produced results that uniquely complement data from currently operating low orbit Earth-observing instruments. In this paper we describe an updated unified approach to EPIC calibration. approach, calibration coefficients and their trends were obtaine...

The Low Earth Orbit (LEO) satellite networks require a reliable handover re-routing protocol that is critical for connections with multihop intersatellite links (ISLs). In this paper, we introduce a footprint handover re-route protocol (FHRP) that maintains the optimality of the initial route without performing a routing algorithm after satellite handovers. Furthermore, the FHRP handles the int...

Low Earth Orbit (LEO) satellites move with respect to a fixed observer on the Earth surface. Satellites in the polar regions and the seam switch off their intersatellite links to the neighbor satellites. As a result, the connectivity pattern of the network changes. Ongoing calls passing through these links need to be rerouted. A large number of simultaneous rerouting attempts would cause excess...

In a LEO system, a user’s call may be handed over constantly from one satellite to another due to visibility changes caused by satellites’ movements. The resultant system performance will degrade if handover calls occur frequently but few are transferred successfully. This paper considered a multiservice LEO system that allows different bandwidth/channel allocations (so-called multirate) on-dem...

Current QoS (quality of service) routing schemes for Polar-orbit low earth orbit (LEO) satellites IP networks has high computation complexity to achieve end-to-end delay guarantee. As a remedy, agentbased QoS routing (AQR) is proposed. AQR is a source-based routing protocol. Once connection requests arrive, QoS mobile agents are dispatched from ingress satellite to explore candidate paths, and ...