Satellite Digital Video Broadcasting Research Articles

PROQOS?Dynamic SLA Management in DiffServ Space Links

Several base elements for the provision of quality of service guarantees have been developed in the recent past. Of these, the Differentiated Services (DiffServ) architecture stands out as the most promising. In spite of this, various issues remain, especially when multidomain DiffServ services are concerned. In this case, some forms of distributed management of Service Level Agreements that allow the specification, exchange, enforcement and monitoring of quality of service data must be in place. Although, again, some isolated solutions exist for each of these problems, considerable effort is necessary to make them work together. The project presented in this paper tried to assess the feasibility of providing differentiated quality of service in satellite IP networks, by developing a dynamic Service Level Agreement management solution for an IP over Digital Video Broadcast Satellite system. The functionality of the implemented system comprises system configuration, dynamic SLA negotiation, QoS monitoring and metering, SLA conformance checking, and QoS reporting to customers.

Efficient non-data-aided carrier and clock recovery for satellite DVB at very low signal-to-noise ratios

This paper deals with the analysis and design of efficient non-data-aided clock and carrier (frequency/phase) synchronization algorithms intended for use in satellite digital video broadcasting systems employing turbo-coding techniques to enhance the power efficiency. The above issue appears quite challenging in view of both the extremely low signal-to-noise ratio, typical of turbo-codes operation, and the very short time allocated to the acquisition of synchronization parameters. These constraints rule out most conventional clock/carrier recovery schemes and demand a careful search for specific, highly efficient algorithms. We propose and analyze a clock/carrier synchronization scheme capable of operating at values of E/sub b//N/sub o/ as low as 1 dB with lock-in delay not exceeding 50 ms.

Digital video broadcasting: Satellite specification

Digital video transmission over satellite channels is described. Many systems have so far been proposed for satellite transmission, and exist in some form. Recently, the European Telecommunications Standard (ETS 300 421) has now been accepted by the Digital Audio-Video Interface Council (DAVIC) as the world standard. In the following, we describe the ETS 300 421 or the DVB-S (Digital Video Broadcasting-Satellite) standard. Specifically, the rationale for the selection of different parameters of the DVB-S standard is explained. Performance of the DVB-S system for a representative case is submitted. Finally, receiver performance issues are addressed.