Provision Of Interactive Services Research Articles

DVB-S2 full cross-layer design for QoS provision

The second generation of the Digital Video Broadcasting standard for Satellite transmission, DVB-S2, is the evolution of the highly successful DVB-S satellite distribution technology. DVB-S2 has benefited from the latest progress in channel coding and modulation such as Low Density Parity Check Codes and higher order constellations to achieve performance that approaches Shannon?s theoretical limit. We present a cross-layer design for Quality-of-Service (QoS) provision of interactive services, which is not specified in the standard. Our cross-layer approach exploits the satellite channel characteristics of space-time correlation via a cross-layer queueing architecture and an adaptive cross-layer scheduling policy. We show that our approach not only allows system load control but also rate adaptation to channel conditions and traffic demands on the coverage area. We also present the extension of our cross-layer design for mobile gateways focusing on the railway scenario. We illustrate the trade-off between system-wide and individual throughput by means of simulation, and that this trade-off could be a key metric in measuring the service level of DVB-S2 Broadband Service.

An Analysis on the Performance of the Forward and Return Interaction Channels in DVB-RCS

The next generation consumer level interactive services require reliable and constant communication for both mobile and static users. The digital video broadcasting (DVB) group has exploited the rapidly increasing satellite technology for the provision of interactive services and launched a standard called digital video broadcast through return channel satellite (DVB-RCS). DVB-RCS relies on DVB-satellite (DVB-S) for the provision of forward channel. The digital signal processing (DSP) implemented in the satellite channel adapter block of these standards use powerful channel coding and modulation techniques. The investigation is concentrated towards the forward error correction (FEC) of the satellite channel adapter block, which will help in determining, how the technology copes with the varying channel conditions and user requirements.