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New generation of satellite systems with on-board processing (switching/routing) and support for multiple spot beams will play a key role in the provision of mobile and ubiquitous Internet-based communications. To achieve this ‘anywhere anytime’ communication in a global multi-beam satellite network with many gateways (GWs), the challenges of beam, gateway and satellite handovers faced by the satellite...
Next-generation satellite systems are expected to provide an overall capacity of Tbit/s, whereby the use of higher frequency bands (e.g., Q, V, or W) will be required. In this regard, the satellite network will implement gateway (GW) diversity schemes and handover techniques to cope with the cases where GW feeder links experience outage due to weather-induced channel degradations. The efficient use...
In this paper we present two enhancements to Contact Graph Routing (CGR), a Delay-/ Disruption- Tolerant Networking routing algorithm developed by NASA JPL for space environments with predetermined connectivity schedules, such as Interplanetary communications and LEO satellite systems. The first enhancement, CGR-ETO, aims to improve the accuracy of predicted bundle delivery time by considering the...
In this work, a game-theoretic analysis of a video exchange application in which two users exchange their video streams over a satellite channel using Quality of Experience (QoE) driven rate adaptation is studied. In such an interaction, users aim at maximizing the Quality of Service (QoS) and QoE of their received video while minimizing their individual cost incurred by their video transmission,...
The dual polarised MIMO land mobile satellite channel offers spatial multiplexing gain for mobile broadcasting systems. Antenna diversity in satellite systems is difficult to obtain, due to the nature of the satellite channel and the absence of scatterers in the vicinity of the satellite transmitter; therefore dual polarisation offers a potential solution in achieving diversity. Receiver based equalisation...
We consider a broadcasting scenario in which multiple beams from one or more satellites serve partially overlapping coverage areas. The satellites transmit in the same frequency band and hence create strong interference between the transmitted data streams, in particular at the intersection of the beams. We evaluate various approaches for interference cancellation at the receiver with varying performance-complexity...
We study the applicability of soft interference cancellation in the forward link of commercial multibeam satellite systems with focus on mobile terminals. We adopt a standard currently used in commercial satellite systems as a reference. The multibeam satellite antenna radiation diagram has been generated using a physical optics reflector model, while state-of-the art channel models have been used...
We consider a Mobile Satellite System (MSS) supporting a very large number of beams and providing service to a massive number of Mobile Satellite Terminals (MST). We identify the challenges posed by the design of such a system and address them. More specifically, we propose algorithms to (a) design adaptive beamformers at the gateway and receivers at the MSTs; (b) acquire knowledge on the channel...
Carrier- and data-blind recovery of the symbol timing is of paramount importance in digital receivers, i.e., detailed knowledge about carrier frequency and phase or any pilot sequences is not necessary for proper operation. In this context, feedforward algorithms are particularly useful in packet-oriented systems, where rapid and stable acquisition of the major transmission parameters is essential...
Due to the scarcity and high cost of satellite frequency spectrum, it is very important to utilize the available spectrum as efficiently as possible. The efficient usage of the spectrum in the satellite return link is a challenging task, especially if multiple users are present. In previous works Multi-User Detection (MUD) techniques have been widely studied to increase the spectral efficiency of...
In the context of satellite communications, random access methods can significantly increase throughput and reduce latency over the network. The recent random access methods are based on multi-user multiple access transmission at the same time and frequency followed by iterative interference cancellation and decoding at the receiver. Generally, it is assumed that perfect knowledge of the interference...
Orbiting satellites and other spatial vehicles have complex trajectories that can usually be precisely approximated with analytical or numerical trajectory estimation algorithms. However, some scenarios, such as LEOP (Launch and Early Orbit Phase) or during critical manoeuvres, present greater angular uncertainty. During these, large dish antennas used for TT&C (Telemetry, Tracking & Command)...
The work presented in this paper aims at illustrating the improvements foreseen for the Payload Data Transmitter of Near Earth and Deep Space scientific missions. Taking advantage of technology evolution combined with innovative architectures and advanced digital signal processing, the paper shows how to increase dramatically the data return in severely power-constrained scenarios, typical of Deep...
This paper focuses on the evolution of communication networks and service delivery. It identifies major trends that will drive the evolution of networks and service delivery in the next years. Among them Software Defined Networking (SDN) is probably the single most important technology evolution trend that will change networking. Based on the identified trends it presents a reference service delivery...
This paper presents a framework for business interoperability with specific focus on the performance indicators and SLA models between terrestrial and satellite operators. It discusses relevant performance metrics currently used in satellite and terrestrial networks as well as the correlation between them and concludes that new KPIs and SLA models as enablers for service delivery over an integrated...
Information-Centric Networking (ICN) has been in the spotlight of recent research efforts. ICN architectures depart from the traditional host-centric (inter-)networking paradigm and leverage the role of information by placing it in the core of all networking functions. A target of ICN is to address the security shortcomings of the legacy host-centric paradigm. In this paper we discuss security requirements...
This paper looks at the implications, benefits and opportunities for integrating satellite links into the Future Internet specifically to provide resilient backhauls in the 5G networks that will emerge. This analysis is based on the study performed under ESA ARTES 1 “Service delivery over integrated satellite and terrestrial networks”, contract 4000106656/12/NL/US. This study considered the integration...
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