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The following topics are dealt with : network coding; automatic identification system; delay tolerant networks; modulation and coding; system architecture; estimation and synchronization theory; multibeam communication; cooperative communication; spectrum sharing; navigation and positioning; signal processing; communication theory; S-band system; and network protocol.
In this paper we extend the analysis of by comparing delay in protocols using retransmission and packet encoding for bidirectional unicast communication over a satellite channel, where the signal propagation delay is significant. We derive results on the total sender-receiver delay based on analysis and computer simulation for a Bernoulli packet arrival distribution.
Mobile terminals communicating through satellite suffer from low channel quality due to the combination of slow and fast fading and limited battery power. Moreover, the advanced applications proliferating over such terminals forbids the use of feedback based packet retransmission schemes over satellite due to their high latency, exceeding three times the round trip time. These feedback based packet...
Future deep space missions are envisioned to implement the Delay Tolerant Network architecture and to offer very high data rate also towards remote planets to support possible human missions. In this perspective, the need for advanced transmission paradigms and reliability means is needed to ensure the success of such missions. On the one hand, the CCSDS protocol implemented at the application and...
Contact Graph Routing is a routing scheme for Delay-and Disruption-Tolerant Networks (DTNs) that is designed particularly for use in highly deterministic space networks. The Endpoint Discovery Protocol is designed for use in terrestrial DTNs where opportunistic contacts are common. We outline two scenarios where use of both of these protocols could be desirable and analyse the current versions to...
In this study, the Symbol error rate (SER) performance of cooperative based downlink satellite system with single terrestrial relay is investigated by using amplify-and-forward cooperation protocol over non identical fading channels. A closed form expression of exact SER over non identical fading channels is derived for M-ary phase shift keying (M-PSK) and M-ary quadrature amplitude modulation (QAM)...
In this paper, we derive an analytical model for the estimation of the overhead introduced in a file transfer procedure by three different reliable protocols, namely TCP, SCTP, and Saratoga. The model estimates the introduced overhead down to the IP layer, taking into account uncorrelated packet loss on the channel. The model distinguishes between the overhead on the forward link (server to client),...
Networking has experienced tremendous changes. Once dedicated to one single type of services, technologies are now offering integrated services: we want to have access to any services anywhere. One challenge is the mobility, with 3G terrestrial offers beginning to be successful. In such a context, satellite systems appear as a real opportunity since they may fill the gap between dense connected areas...
The 2nd generation of Digital Video Broadcasting for Satellite (DVB-S2) standards allows the direct transmission of IP content using the Generic Stream Encapsulation (GSE) protocol, replacing the existing Transport Stream (MPEG-2 TS). This represents an evolution from the two current encapsulation methods: the native use of the Packetized Elementary Stream (PES) over TS for MPEG-2 encoded applications...
We consider a communication network with a single source node, a single destination node, and N intermediate nodes. We propose efficient techniques to increase the spectral efficiency of cooperative multihop transmission. We analyze the minimum total transmit power needed to achieve a desired end-to-end outage probability for a given rate for several schemes. In the first scheme, incremental relaying,...
This paper makes a survey of current trends and perspectives in the development of mobile satellite services in S-band in Europe. We present the recent evolutions and current status of different ongoing projects. We also identify current technology challenges and key drivers in the future evolution.
This paper gives an overview of a suitable communications system capable of efficiently use the available S-band allocation for pan-European Mobile Satellite Services (15 MHz in both uplink and downlink for each of the two licensed operators) to provide different classes of services such as interactive mobile broadcast services enhancing DVB-SH offer, messaging services for handheld and vehicular...
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