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Video Broadcasting (video + broadcasting)

Distribution by Scientific Domains
Engineering100%

Selected Abstracts

Performance evaluation of TCP-based applications over DVB-RCS DAMA schemes

INTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, Issue 3 2009
M. Luglio
Abstract Transmission Control Protocol (TCP) performance over Digital Video Broadcasting,Return Channel via Satellite (DVB-RCS) standard is greatly affected by the total delay, which is mainly due to two components, propagation delay and access delay. Both are significant because they are dependent on the long propagation path of the satellite link. The former is intrinsic and due to radio wave propagation over the satellite channel for both TCP packets and acknowledgements. It is regulated by the control loop that governs TCP. The latter is due to the control loop that governs the demand assignment multiple access (DAMA) signalling exchange between satellite terminals and the network control center, necessary to manage return link resources. DAMA is adopted in DVB-RCS standard to achieve flexible and efficient use of the shared resources. Therefore, performance of TCP over DVB-RCS may degrade due to the exploitation of two nested control loops also depending on both the selected DAMA algorithm and the traffic profile. This paper analyses the impact of basic DAMA implementation on TCP-based applications over a DVB-RCS link for a large set of study cases. To provide a detailed overview of TCP performance in DVB-RCS environment, the analysis includes both theoretical approach and simulation campaign. Copyright © 2009 John Wiley & Sons, Ltd. [source]

Fusion of digital television, broadband Internet and mobile communications,Part I: Enabling technologies

INTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, Issue 4 2007
F. L. C. Ong
Abstract The introduction of digital video broadcasting (DVB) satellite systems has become an important tool for future mobile communication and is currently a focus in several research areas such as the integration of DVB satellite systems with different wireless technologies. This tutorial consists of two parts, Enabling technologies and Future service scenarios, which aims to provide an introduction to the current state-of-the-art of DVB standards over satellite and its fusion with mobile and Internet technologies. This paper, Enabling technologies, focuses on providing an overview of the different technologies and issues that facilitates better understanding of the current and future operational scenarios, whereas the second paper, Future service scenarios will emphasize future research directions in this research area. In the first part, the paper will initially be focused on the introduction of different DVB satellite systems, i.e. DVB- via satellite (DVB-S), DVB return channel by satellite (DVB-RCS) and second-generation DVB system for broadband satellite services (DVB-S2). This is then followed by a description of the different Internet Protocol (IP) technologies used to support macro- and micro-mobility and the migration strategies from IP version 4 (IPv4) to IP version 6 (IPv6). Finally, the different security mechanisms for the DVB system and end-to-end satellite network are addressed. Copyright © 2007 John Wiley & Sons, Ltd. [source]

Cross-layer protocol optimization for satellite communications networks: a survey

INTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, Issue 5 2006
Giovanni Giambene
Abstract Satellite links are expected to be one important component of the next-generation Internet. New satellite system architectures are being envisaged to be fully IP based and support digital video broadcasting and return channel protocols (e.g. DVB-S, DVB-S2 and DVB-RCS). To make the upcoming satellite network systems fully realizable, meeting new services and application requirements, a complete system optimization is needed spanning the different layers of the OSI, and TCP/IP protocol stack. This paper deals with the cross-layer approach to be adopted in novel satellite systems and architectures. Different cross-layer techniques will be discussed, addressing the interactions among application, transport, MAC and physical layers. The impacts of these techniques will be investigated and numerical examples dealing with the joint optimization of different transport control schemes and lower layers will be considered referring to a geostationary-based architecture. Our aim is to prove that the interaction of different layers can permit to improve the higher-layer goodput as well as user satisfaction. Copyright © 2006 John Wiley & Sons, Ltd. [source]

DVB-S2 low density parity check codes with near Shannon limit performance

INTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, Issue 3 2004
Mustafa Eroz
Abstract Low density parity check (LDPC) codes are chosen for the second generation digital video broadcasting (DVB) standard. In this paper, we review LDPC codes in general, present belief propagation decoding algorithm in simple terms, describe the standardized LDPC codes and show their performance. Copyright © 2004 John Wiley & Sons, Ltd. [source]

Visible light communication systems for optical video transmission

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 7 2010
J. Rufo
Abstract This article describes an optical wireless system based on visible light communication (VLC), which allows a video broadcasting to reach a bit rate of 1 Mbps, although this system can also be used for low-speed sensor interconnections. The main advantages of this technology are the robustness against EM interference, safety for human eye, and security against undesired network access. In this article, we present the electronic structure of a low-cost VLC transceiver, the modulation process and the Ethernet interface that has been implemented in each AP (access point). Finally, some conclusions are drawn. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1572,1576, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25236 [source]