Dissertationen zum Thema „Multimedia broadcasting“
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Tarus, Hillary Kiplagat. „Bluecastor : Bluetooth multimedia broadcasting“. Thesis, University of Strathclyde, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.510720.
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2
Pullano, Valentina <1983>. „Reliable Broadcasting and Streaming of Multimedia Content“. Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5653/1/Pullano_Valentina_Tesi.pdf.
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This thesis is focused on the study of techniques that allow to have reliable transmission of multimedia content in streaming and broadcasting applications, targeting in particular video content. The design of efficient error-control mechanisms, to enhance video transmission systems reliability, has been addressed considering cross-layer and multi-layer/multi-dimensional channel coding techniques to cope with bit errors as well as packet erasures. Mechanisms for unequal time interleaving have been designed as a viable solution to reduce the impact of errors and erasures by acting on the time diversity of the data flow, thus enhancing robustness against correlated channel impairments. In order to account for the nature of the factors which affect the physical layer channel in the evaluation of FEC schemes performances, an ad-hoc error-event modeling has been devised. In addition, the impact of error correction/protection techniques on the quality perceived by the consumers of video services applications and techniques for objective/subjective quality evaluation have been studied. The applicability and value of the proposed techniques have been tested by considering practical constraints and requirements of real system implementations.
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Pullano, Valentina <1983>. „Reliable Broadcasting and Streaming of Multimedia Content“. Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5653/.
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This thesis is focused on the study of techniques that allow to have reliable transmission of multimedia content in streaming and broadcasting applications, targeting in particular video content. The design of efficient error-control mechanisms, to enhance video transmission systems reliability, has been addressed considering cross-layer and multi-layer/multi-dimensional channel coding techniques to cope with bit errors as well as packet erasures. Mechanisms for unequal time interleaving have been designed as a viable solution to reduce the impact of errors and erasures by acting on the time diversity of the data flow, thus enhancing robustness against correlated channel impairments. In order to account for the nature of the factors which affect the physical layer channel in the evaluation of FEC schemes performances, an ad-hoc error-event modeling has been devised. In addition, the impact of error correction/protection techniques on the quality perceived by the consumers of video services applications and techniques for objective/subjective quality evaluation have been studied. The applicability and value of the proposed techniques have been tested by considering practical constraints and requirements of real system implementations.
4
Du, Hongfei. „Efficient radio resource management for satellite digital multimedia broadcasting“. Thesis, University of Surrey, 2007. http://epubs.surrey.ac.uk/843539/.
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In recent years, there has been tremendous growth in digital multimedia technologies, from voice to data to video, and the recent, but growing, demand of supporting diverse quality of service (QoS) guarantees. It places new demands for future wireless networks in utilising the available radio resource in a more efficient and effective way. The key to this demand is the involvement of efficient radio resource management (RRM), to provide various QoS support for multimedia service delivery. Due to the unique broadcast nature and ubiquitous coverage of satellite communication system, the synergy between satellite networks and terrestrial networks provides new opportunities for delivering point-to-multipoint (or one-to-many) multimedia content to a large audience spread over extensive geographical area. It is expected that the satellite component will play a complementary, but essential, role in delivering multimedia data to those areas where the terrestrial high-bandwidth communication infrastructures are, either economically or technically, unreachable. The emphasis throughout this research is on the potential optimization techniques pertinent to the RRM to facilitate multimedia broadcast/multicast service (MBMS) delivery over the satellite digital multimedia broadcasting (SDMB) system, which has emerged as one of the most promising approaches for this mission. We concentrate on the algorithm development and performance evaluation of RRM strategies implemented at the radio access layer in the SDMB system, aimed at the efficient delivery of multimedia applications to mobile users at satisfactory QoS. Firstly, we have developed a novel two-level channel multiplexing scheme for the radio resource allocation (RRA), which is capable of optimally performing both logical and transport channel multiplexing via two new optimization algorithms, namely optimum estimation algorithm (OEA) and power-oriented adaptation (POA) algorithm. Simulation results prove that the proposed scheme can effectively improve the performance in terms of channel utilisation, power consumption as well as transmission capacity. Secondly, we have investigated the optimization of packet scheduling algorithms via the various adaptations of a proportional differentiation model. By taking into account multiple performance measures, e.g., buffer occupancy, queuing delay and data rate, several novel algorithms, i.e. buffer-length related queue (BLRQ), delay differentiation queue (DDQ) and combined delay and rate differentiation (CDRD), are introduced for performing the packet scheduling task in SDMB. Their performance has been evaluated via simulation means and compared with existing schemes. It is demonstrated that the proposed proportional differentiation packet scheduling schemes can achieve significant performance improvements in queuing delay, jitter and channel utilisation. Finally, we further optimize the packet scheduling schemes by using cross-layer design and adaptive optimization mechanisms. Cross-layer joint priority queue (CJPQ) and adaptive multidimensional QoS-based (AMQ) packet scheduling algorithms are introduced within this context and investigated via simulations. It is shown that these proposals can significantly improve the QoS performance amongst heterogeneous competing flows in terms of both scheduling efficiency and fairness, offering better flexibility and scalability features.
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Naeimipoor, Farahnaz. „Video Streaming and Multimedia Broadcasting Over Vehicular Ad Hoc Networks“. Thèse, Université d'Ottawa / University of Ottawa, 2013. http://hdl.handle.net/10393/23763.
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Video dissemination capabilities are crucial for the deployment of many services over
VANETs. These services range from enhancing safety via the dissemination of video
from the scene of an accident, to advertisement of local services or businesses. This work
considers the infrastructure-less scenario of VANETs and dissemination of video content
over this network environment, which is extremely challenging mainly due to its dynamic
topology and stringent requirements for video streaming.
This study discusses issues and challenges that need to be tackled for disseminating
high-quality video over VANETs. Furthermore it surveys and analyzes the suitability
of different existing solutions aimed towards effective and efficient techniques for video
dissemination in vehicular networks. As a result, a set of the most promising techniques
are selected, described in detail and evaluated based on standard terms in quality of
service. This thesis also discusses efficiency and suitability of these techniques for video
dissemination and compares their performance over the same network condition. In
addition, a detailed study on the effect of network coding on video dissemination protocols
has been conducted to guide how to employ this technique properly for video streaming
over VANETs. From this study, a summary of the observations was obtained and used
to design a new hybrid solution by deploying robust and efficient techniques in number
of existing protocols in an optimal manner. The proposed hybrid video dissemination
protocol outperforms other protocols in term of delivery ratio and complies with other
quality-of-service requirements for video broadcasting over vehicular environments.
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Gozálvez, Serrano David. „Combined Time, Frecuency and Space Diversity in Multimedia Mobile Broadcasting Systems“. Doctoral thesis, Universitat Politècnica de València, 2012. http://hdl.handle.net/10251/16273.
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El uso combinado de diversidad en el dominio temporal, frecuencial y espacial constituye una valiosa herramienta para mejorar la recepción de servicios de difusión móviles. Gracias a la mejora conseguida por las técnicas de diversidad es posible extender la cobertura de los servicios móviles además de reducir la infraestructura de red. La presente tesis investiga el uso de técnicas de diversidad para la provisión de servicios móviles en la familia europea de sistemas de difusión terrestres estandarizada por el prpoyecto DVB (Digital Video Broadcasting). Esto incluye la primera y segunda generación de sistemas DVB-T (Terrestrial), DVB-NGH (Handheld), y DVB-T2 (Terrestrial 2nd generation), así como el sistema de siguiente generación DVB-NGH. No obstante, el estudio llevado a cabo en la tesis es genérico y puede aplicarse a futuras evoluciones de estándares como el japonés ISDB-T o el americano ATSC.
Las investigaciones realizadas dentro del contexto de DVB-T, DVB-H y DVBT2 tienen como objetivo la transmisión simultánea de servicios fijos y móviles en redes terrestres. Esta Convergencia puede facilitar la introducción de servicios móviles de TB debido a la reutilización de espectro, contenido e infraestructura. De acuerdo a los resultados, la incorporación de entrelazado temporal en la capa física para diversidad temporal, y de single-input multiple-output (SIMO) para diversidad espacial, son esenciales para el rendimiento de sistemas móviles de difusión. A pesar de que las técnicas upper later FEC (UL-FEC) pueden propocionar diversidad temporal en sistemas de primera generación como DVB-T y DVB-H, requieren la transmisión de paridad adicional y no son útiles para la recepción estática. El análisis en t�ñerminos de link budjget revela que las técnicas de diversidad noson suficientes para facilitar la provision de servicios móviles en redes DVB-T y DVB-T2 planificadas para recepción fija. Sin embargo, el uso de diversidad en redes planificadas para recepción portableGozálvez Serrano, D. (2012). Combined Time, Frecuency and Space Diversity in Multimedia Mobile Broadcasting Systems [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/16273
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Bria, Aurelian. „Mobile Multimedia Multicasting in Future Wireless Systems : A Hybrid Cellular-Broadcasting System Approach“. Doctoral thesis, Stockholm : Informations- och kommunikationsteknik, Kungliga Tekniska högskolan, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-9795.
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Bush, John Michael. „Multimedia content and service delivery using an infostation network based upon digital video broadcasting“. Thesis, University of Strathclyde, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.436846.
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Gómez, Barquero David. „COST EFFICIENT PROVISIONING OF MASS MOBILE MULTIMEDIA SERVICES IN HYBRID CELLULAR AND BROADCASTING SYSTEMS“. Doctoral thesis, Universitat Politècnica de València, 2010. http://hdl.handle.net/10251/6881.
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Uno de los retos a los que se enfrenta la industria de las comunicaciones móviles e inalámbricas es proporcionar servicios multimedia masivos a bajo coste, haciéndolos asequibles para los usuarios y rentables a los operadores. El servicio más representativo es el de TV móvil, el cual se espera que sea una aplicación clave en las futuras redes móviles. Actualmente las redes celulares no pueden soportar un consumo a gran escala de este tipo de servicios, y las nuevas redes de radiodifusión móvil son muy costosas de desplegar debido a la gran inversión en infraestructura de red necesaria para proporcionar niveles aceptables de cobertura.
Esta tesis doctoral aborda el problema de la provisión eficiente de servicios multimedia masivos a dispositivos móviles y portables utilizando la infraestructura de radiodifusión y celular existente. La tesis contempla las tecnologías comerciales de última generación para la radiodifusión móvil (DVB-H) y para las redes celulares (redes 3G+ con HSDPA y MBMS), aunque se centra principalmente en DVB-H. El principal paradigma propuesto para proporcionar servicios multimedia masivos a bajo coste es evitar el despliegue de una red DVB-H con alta capacidad y cobertura desde el inicio. En su lugar se propone realizar un despliegue progresivo de la infraestructura DVB-H siguiendo la demanda de los usuarios. Bajo este contexto, la red celular es fundamental para evitar sobre-dimensionar la red DVB-H en capacidad y también en áreas con una baja densidad de usuarios hasta que el despliegue de un transmisor o un repetidor DVB-H sea necesario. Como principal solución tecnológica la tesis propone realizar una codificación multi-burst en DVB-H utilizando códigos Raptor. El objetivo es explotar la diversidad temporal del canal móvil para aumentar la robustez de la señal y, por tanto, el nivel de cobertura, a costa de incrementar la latencia de la red.Gómez Barquero, D. (2009). COST EFFICIENT PROVISIONING OF MASS MOBILE MULTIMEDIA SERVICES IN HYBRID CELLULAR AND BROADCASTING SYSTEMS [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/6881
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Galipeau, Marcy. „New Media: Threat or Opportunity? Finding a Way to Balance New Media Initiatives within the Traditional Broadcasting World“. Thesis, University of Ottawa (Canada), 2010. http://hdl.handle.net/10393/28726.
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This research aggregated key elements discussed during the CRTC Public Hearing on New Media, in order to examine fundamentals for the development of sustainable business models within the new media environment. The use of a qualitative methodology allowed the progressive gathering of in-depth information. Three main data collection techniques were used to obtain the desired information. First, an observational case study focused on the new media public proceeding. Second, a thorough content analysis examined public submissions through grids in order to extract relevant data. Third, formal interviews with regulatory experts were used to access information at a more intimate level. In the context of this study five media groups were chosen for examination. This would include, private broadcasters, public broadcasters, the culture and independent producers sector, telecommunications companies and Internet Service Providers. This gave an overall view of each sector within the Canadian broadcasting system. As a result of this research, the Canadian media industries will have to make urgent changes. To begin, platform-specific content production will be vital to the overall success of the system. This would allow proper distribution, minimizing the need of reformatting the content. Accordingly, maximizing the use of content will ensure that Canadians have access to programming that reflects their realities. Most companies agreed that new online advertising funding methods were needed, that new media initiatives generated economic growth and that content ownership should be a priority for upcoming regulatory decisions.
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Luh, William. „Collusion-resistant fingerprinting for multimedia in a broadcast channel environment“. Texas A&M University, 2004. http://hdl.handle.net/1969.1/1478.
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Digital fingerprinting is a method by which a copyright owner can uniquely
embed a buyer-dependent, inconspicuous serial number (representing the fingerprint)
into every copy of digital data that is legally sold. The buyer of a legal copy is
then deterred from distributing further copies, because the unique fingerprint can be
used to trace back the origin of the piracy. The major challenge in fingerprinting is
collusion, an attack in which a coalition of pirates compare several of their uniquely
fingerprinted copies for the purpose of detecting and removing the fingerprints.
The objectives of this work are two-fold. First, we investigate the need for robustness
against large coalitions of pirates by introducing the concept of a malicious
distributor that has been overlooked in prior work. A novel fingerprinting code that
has superior codeword length in comparison to existing work under this novel malicious
distributor scenario is developed. In addition, ideas presented in the proposed
fingerprinting design can easily be applied to existing fingerprinting schemes, making
them more robust to collusion attacks.
Second, a new framework termed Joint Source Fingerprinting that integrates the
processes of watermarking and codebook design is introduced. The need for this new
paradigm is motivated by the fact that existing fingerprinting methods result in a
perceptually undistorted multimedia after collusion is applied. In contrast, the new
paradigm equates the process of collusion amongst a coalition of pirates, to degrading
the perceptual characteristics, and hence commercial value of the multimedia in question.
Thus by enforcing that the process of collusion diminishes the commercial value
of the content, the pirates are deterred from attacking the fingerprints. A fingerprinting
algorithm for video as well as an efficient means of broadcasting or distributing
fingerprinted video is also presented. Simulation results are provided to verify our
theoretical and empirical observations.
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Dikweni, Lulama. „An assessment of the health channel broadcasting multimedia for communication and dissemination of information in the health sector“. Thesis, Stellenbosch : University of Stellenbosch, 2006. http://hdl.handle.net/10019.1/17349.
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Thesis (MPhil)--University of Stellenbosch, 2006.ENGLISH ABSTRACT: The study reported on here was conducted between December 2003 and April 2004. The aim of the study was to assess the use of Health Channel Broadcast Multimedia (HCBM) in order to maximise its success. The HCBM is an Information Technology method that was used to disseminate health information in public health facilities. HCBM was installed in health facilities and was used as an education tool. This was done by further developing the clinical skills of the health care workers (HCWs) and to inform the patients, including the community members on HIV/AIDS and related communicable diseases. The study was conducted in eight health facilities in seven provinces where HCBM was piloted. Facilities and forty-nine health professionals (HCWs) were selected conveniently and one hundred and twenty-eight patients were sampled using a systematic random method. The convenient sampling method was relevant since these were key facilities with HCBM. There were very few HCWs who did view HCBM and they were drawn into the study. HCBM used programmes disseminating messages in Afrikaans, English, sePedi, seSotho, siSwati, isiXhosa and isiZulu. The Rapid Assessment Response (RAR) approach was used to give a quick appraisal of the study. The report focuses on the cross-sectional reporting of the quantitative technique of the RAR. Of the HCWs, 86% had viewed the broadcast content, 70% were satisfied with the broadcast mode of service delivery; 56% indicated that the messages were good and added educational value to their professional work, while 52% chose to use the IP box content with HIV/AIDS topics. Ninety-two percent of HCWs stated that HCBM targeted patients and young people, 48% said HCBM had the ability to convey information and 48% said it was capable of addressing health problem. When HCBM was being set up, 62% HCWs engaged in decision making. Patients mentioned that HCBM as a method of information dissemination was educative (62%) and informative (52%). They reported that they did hear messages on HIV/AIDS telling them that medication was available for free to treat within 72 hours after being raped (72%); they had the right to say no to unsafe sex (92%); and 76% said the broadcast had the ability to change people’s behaviour. Respondents reported that the messages were easily understood (44%). The conclusion is that the findings will be useful to inform the government and managers of HCBM programmes on how to maximise the success of HCBM, especially at the implementation phase.
AFRIKAANSE OPSOMMING: Hierdie verslag doen verslag oor die resultate van ’n ondersoek wat tussen Desember 2003 en April 2004 onderneem is. Die doel van die verslag is om die doeltreffendheid van die gebruik van ’n multimedia gesondheidsuitsendingkanaal, Health Channel Broadcast Multimedia (HCBM) te bepaal. Hierdie is nuwe tegnologie wat gebruik word om gesondheidsinligting slegs in die openbare gesondheidsektor te versprei. Die studie is by agt openbare gesondheidsfasiliteite in sewe provinsies waar die HCBM volledig gevestig was, onderneem. Nege-en-veertig gesondheidskundiges (HPW’s) is volgens ’n gerieflikheidsteekproef geselekteer, en 128 pasiënte is met behulp van ’n sistematiese ewekansige steekproef geselekteer. Die HCBM het programme gebruik wat boodskappe in Afrikaans, Engels, sePedi, seSotho, siSwati, isiXhosa en isiZulu uitgesaai het. ’n Benadering bekend as die Rapid Assessment Response (RAR) is gebruik om ’n vinnige evaluering van die studie te maak. Die verslag konsentreer op die deursneerapportering van die kwantitatiewe tegniek van die RAR. Van die HPW’s het 85% na die inhoud van die uitsending gekyk, 70% was tevrede met die uitsendingmodus van dienslewering, 56% het aangedui dat die boodskappe goed was en van opvoedkundige waarde in hulle professionele werk, terwyl 52% verkies het om die Internet Platform-inhoud met MIV/Vigs-temas te gebruik. Twee-en-negentig persent van die HPW’s het te kenne gegee die HCBM is gerig op pasiënte en die jeug, 48% het gesê HCBM het die vermoë om inligting oor te dra, en 48% het gesê dit is geskik om na die gesondheidsprobleem om te sien. Tydens die instelling van die HCBM het 62% HPW’s aan besluitneming deelgeneem. Van die pasiënte met grade 0–6 as opvoedingspeil het 75% verkies om brosjures te gebruik bo enige ander massamedia, en 72% mans en 67% vrouens het na boodskappe oor die behandeling van MIV/Vigs-simptome geluister. Inligting oor vrywillige berading en toetsing voor swangerskap is deur 66% van die vrouens gehoor. Meer as 90% van hulle was bewus van die reg om nee te sê vir seks of onveilige seks. Pasiënte oor die hele residensiële gebied was dit eens dat die taalgebruik in die uitsendings maklik verstaanbaar was. Oor al die opvoedkundige grade heen is saamgestem dat die HCBM die voorgenome boodskap oorgedra het. Die gevolgtrekking is dat die bevindings waardevol is om die regering en bestuurders van die uitsendingsprogram in te lig oor hoe om die ander fases te verbeter. Dit sluit Fase 2 in, wat die uitvoering van die HCBM behels.
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Zafalão, Rogerio Makiyama. „Protocolos de difusão periodica de video sob limitação de banda passante“. [s.n.], 2003. http://repositorio.unicamp.br/jspui/handle/REPOSIP/276397.
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Orientador : Nelson Luis Saldanha da FonsecaDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Computação
Made available in DSpace on 2018-08-03T23:48:34Z (GMT). No. of bitstreams: 1 Zafalao_RogerioMakiyama_M.pdf: 562652 bytes, checksum: 8fef838d9bae43c90f268cf88c61b763 (MD5) Previous issue date: 2003
Resumo: Sistemas de Video sob Demanda possibilitam ao usuário a escolha de vídeos para exibiçao dentre uma vasta coleção. Como a transmissão de um fluxo de vídeo demanda uma grande quantidade de bande passante, estratégias de compartilhamento da transmissão de fluxos de vídeo são utilizadas para reduzir esta demanda. Dentre estas técnicas, os protocolos baseados em difusão periódica são indicados para a transmissão dos vídeos mais requisitados, uma vez que estes utilizam largura de banda constante independente do número de usuários. Entretanto, os protocolos mais eficientes nao levam em consideração limitações de banda passante existentes no cliente. Nesta dissertação, dois protocolos de difusão periódica otimamente estruturados são estendidos de forma a permitir que clientes sujeitos a limitações de largura de banda possam utilizar serviços de Vídeo sob Demanda baseados em difusão periódica
Abstract: Video on Demand (VoD) services allow users to watch movies of their choice among a wide collection. As video transmition requires a huge amount of bandwidth, stream sharing techniques has been developed to reduce the bandwidth requirements. Among these techniques, periodic broadcasting protocols are indicated to transmit most frequently requested videos, since they require a constant amount of bandwidth. However, these protocolos do not consider users with limited bandwidth. In this dissertation two new protocols are introduced, the Polyharmonic Broadcasting with Limited User Bandwidth (PHB-LUB) and the Greedy Equal-Bandwidth Broadcasting with Limited User Bandwidth (GEBB-LUB)
Mestrado
Ciência da Computação
Mestre em Ciência da Computação
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Fuel, Isaias Carlos. „Perceived usefulness of agricultural information sought on-line and broadcast in rural Mozambique: a case study of two Community Multimedia Centres (CMCs)“. Thesis, Rhodes University, 2013. http://hdl.handle.net/10962/d1007240.
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The wealth of information available on the Internet holds the potential to aid development in Africa. In order to be effective, such information needs to be contextualised to respond to local needs and practices. The combination of old and new media can support uptake and improve acceptance of new technologies in developing countries. The purpose of this qualitative study was to investigate the perceived usefulness of agricultural information sought on-line and broadcast via community radio in the two Community Multimedia Centres (CMCs) of Namaacha and Murrombene, in rural Mozambique. The data was generated from focus group discussion, individual interview, document analysis, and observation involving farmers and radio presenters. The study has shown that on-line agricultural information responds to the needs of the farmers because it contributes to eliminate pests and help farmers to make decisions about their activities. The study has also shown that there is a communication gap between farmers, extension workers, and volunteer reporters working at the community radios of the two CMCs. Volunteers have no agricultural knowledge. The problem this creates manifests itself primarily when they try to translate on-line agricultural information from Portuguese into local languages. Farmers have difficulties expressing their problems. Extension workers are not available to act as experts and mediators between volunteers and farmers. A collaborative website focusing on locally relevant content was suggested as a possible improvement.
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Bouzakaria, Nassima. „Contributions au streaming HTTP adaptatif avancé“. Electronic Thesis or Diss., Paris, ENST, 2017. http://www.theses.fr/2017ENST0037.
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Le streaming adaptatif HTTP est une technologie récente dans les communications multimédia, utilisant notamment le standard MPEG-DASH. L'un des principaux problèmes dans le déploiement des services de streaming en direct est la réduction de plusieurs types de latence tel que le délai de démarrage et la latence de bout en bout. Dans cette thèse, nous abordons le problème de ces latences dans les services de streaming en direct utilisant MPEG-DASH. Tout d'abord, nous examinons les causes du délai de démarrage dans les systèmes MPEG-DASH et les stratégies communes pour réduire ce délai. Nous proposons une nouvelle méthode basée sur HTTP / 1.1 qui est compatible avec les infrastructures Web existantes. Deuxièmement, nous étudions les principaux composants qui sont à l’origine de la latence totale, nous proposons un système de streaming en direct à faible latence. Troisièmement, nous montrons comment un système de streaming en direct utilisant MPEG-DASH et à faible latence peut être combiné avec un système utilisant un réseau Broadcast. Notre approche proposée garantit la synchronisation des deux contenus transmis via deux réseaux de distribution DASH et broadcastHTTP adaptive streaming is a recent topic in multimedia communications with on-going standardization activities, especially with the MPEG-DASH standard which covers on demand and live services. One of the main issues in live services deployment is the reduction of various latencies, the initial delay before the playback and the overall end-to-end latency. In this thesis, we address the problem of these latencies in live DASH streaming. First, we review the causes of startup delay in DASH and common strategies used to reduce this delay. We propose a new method based on HTTP/1.1 and compatible with existing caching and delivery infrastructures for reducing the initial setup of an MPEG-DASH session. Second, we investigate the major contributor components to the end-to-end latency. We propose a complete novel low latency live DASH streaming system. Third, we show how such a low latency live DASH system can be used to enable combined broadcast and broadband services while keeping the client buffering requirements on the broadcast link low. Our proposed approach insures two functionalities: synchronization of both contents delivered through different distribution networks and keeping the client buffering requirements on the broadcast link low
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Irani, Ramin. „Error Detection for DMB Video Streams“. Thesis, Blekinge Tekniska Högskola, Sektionen för ingenjörsvetenskap, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-5086.
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The purpose of this thesis is to detect errors in Digital Multimedia Broadcasting (DMB) transport stream. DMB uses the MPEG-4 standard for encapsulating Packetized Elementary Stream (PES), and uses the MPEG-2 standard for assembling them in the form of transport stream packets. Recently many research works have been carried out about video stream error detection. They mostly do this by focusing on some decoding parameters related to frame. Processing complexity can be a disadvantage for the proposed methods. In this thesis, we investigated syntax error occurrences due to corruption in the header of the video transport stream. The main focus of the study is the video streams that cannot be decoded. The proposed model is implemented by filtering video and audio packets in order to find the errors. The filters investigate some sources that can affect the video stream playback. The output from this method determines the type, location and duration of the errors. The simplicity of the structure is one of advantages of this model. It can be implemented by three simple filters for detecting errors and a “calculation unit” for calculating the duration of an error. Fast processing is another benefit of the proposed model.
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Olivier, Jak. „The possibilities provided by subtitling to the SABC TV in the recognition and protection of language rights“. Thesis, Potchefstroom University for Christian Higher Education, 2003. http://hdl.handle.net/10919/71575.
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The degree to which the SABC (South African Broadcasting Corporation) as public broadcaster gives shape to its language policy and language mandate, against the background of an investigation of language rights, establishes the central problem statement of this research.It is widely acknowledged that it is difficult to define the concept of language rights. Although the language-sociological literature associates this concept with minority and cultural rights, it can also be seen as individual rights. According to the Constitution of the Republic of South Africa, 1996, it is clear that language rights should be seen as individual rights that can be exercised within a particular community. Although this dissertation provides an extensive juridical and language sociological explanation of the concept of language rights, the description by Judge Albie Sachs will be used as a working definition for this research. His division between the following four fundamental language rights, viz.: (i) the right to use your language; (ii) the right to develop your language; (iii) the right to be understood and to understand other languages as well as (iv) the right not to be discriminated against because of your language, provides a useful investigation instrument with which the degree to which the SABC-TV acknowledges and protects language rights can be measured.It is found that despite the policy documents on national and corporate level that has equal consideration and treatment of the diverse South African languages in mind, it still happens that the SABC-TV fails to give form to the language rights of individuals that belong to indigenous minority language groups in South Africa. Due to this, the research suggests that the extensive implementation of subtitles, as a form of screen translation that differs from lip synchronised dubbing, can make a significant contribution to the acknowledgement and protection of language rights by the SABC-TV.In addition to a discussion on what subtitles entail, the technical nature and specific parameters thereof, a feasibility study is included within which the affordability of this project for the SABC-TV is indicated. It is found that this form of screen translation is ideal for the South African situation because it is cheaper than both lip synchronised dubbing and the creation of new television programmes, but also because it can effectively be employed in regional broadcasts. Furthermore, the use of bilingual subtitles and pivot subtitles are also alternatives that may be considered. It is essential though that subtitles can indeed contribute to the way in which the SABC, as a public broadcaster, acknowledges and protects the fundamental language rights of the multitude of South Africans that belong to different language communities in South Africa. (Written in Afrikaans)
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Cavallini, Andrea. „I sistemi di diffusione multimediali: il Digital Video Broadcasting (DVB)“. Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amslaurea.unibo.it/2989/.
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In questo elaborato, dopo una descrizione delle procedure per la creazione degli standard per il il broadcasting numerico adottate dal DVB forum, vengono presi in considerazione i trends del mercato del broadcasting numerico e analizzato in dettaglio lo standard utilizzato per la diffusione televisiva terrestre DVB-T e la sua evoluzione DVB-T2.
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Berger, Arne, Maximilian Eibl, Stephan Heinich, Robert Knauf, Jens Kürsten, Albrecht Kurze, Markus Rickert und Marc Ritter. „Schlussbericht zum InnoProfile Forschungsvorhaben sachsMedia - Cooperative Producing, Storage, Retrieval, and Distribution of Audiovisual Media (FKZ: 03IP608)“. Universitätsbibliothek Chemnitz, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-96922.
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In den letzten 20 Jahren haben sich in Sachsen mit ca. 60 Sendern die meisten privaten regionalen Fernsehsender der Bundesrepublik etabliert. Diese übernehmen dabei oft Aufgaben der Informationsversorgung, denen die öffentlich-rechtlichen Sender nur unzureichend nachkommen. Das InnoProfile Forschungsvorhaben sachsMedia fokussierte auf die existentielle und facettenreiche Umbruchschwelle kleiner und mittelständischer Unternehmen aus dem Bereich der regionalen Medienverbreitung. Besonders kritisch für die Medienbranche war der Übergang von analoger zu digitaler Fernsehausstrahlung im Jahr 2010. Die Forschungsinitiative sachsMedia nahm sich der zugrundeliegenden Problematiken an und bearbeitete grundlegende Forschungsfragen in den beiden Themenkomplexen Annotation & Retrieval und Mediendistribution. Der vorliegende Forschungsbericht fasst die erreichten Ergebnisse zusammen.
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Liu, Ming. „Analyse et optimisation du système asiatique de diffusion terrestre et mobile de la télévision numérique“. Phd thesis, INSA de Rennes, 2011. http://tel.archives-ouvertes.fr/tel-00662247.
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Cette thèse a pour objectif l'analyse du système de télévision numérique chinois (DTMB) et l'optimisation de sa fonction d'estimation de canal. Tout d'abord, une analyse approfondie de ce système est effectuée en comparaison du système DVB-T en termes de spécifications, d'efficacité spectrale et de performances. Ensuite, la fonction d'estimation de canal basée sur la séquence pseudo-aléatoire du système est étudiée dans les domaines temporel et fréquentiel, et plusieurs améliorations sont apportées aux méthodes typiques afin de notamment gérer les canaux très dispersifs en temps. Enfin, de nouveaux procédés itératifs aidés par les données et peu complexes sont proposés pour raffiner les estimés de canal. Les fonctions de décodage de canal et d'entrelacement sont exclues de la boucle et des fonctions de filtrage temps/fréquence sont étudiées pour fiabiliser les estimations. Ces nouveaux algorithmes démontrent leur efficacité par rapport aux méthodes courantes de la littérature.
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González, Díaz Paloma. „Prácticas artísticas digitales y tecnologías de control y vigilancia (2001- 2010)“. Doctoral thesis, Universitat de Barcelona, 2013. http://hdl.handle.net/10803/130965.
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El uso masivo de tecnologías de registro y vigilancia por parte del estado y de empresas privadas, corrobora la evolución y trascendencia actual de la propuesta ideada por Jeremy Bentham en el siglo XVIII: El Panóptico. Su modelo de funcionamiento se ha incorporado y expandido en nuestra sociedad con tal intensidad, que cada vez son más las prácticas artísticas contemporáneas que cuestionan su existencia y eficacia.
El interés primordial de nuestro estudio es analizar éste fenómeno y su evolución en el ámbito del new media art, concretamente en las creaciones digitales de la primera década del siglo (2001-2010). Durante este periodo se amplían y diversifican las tecnologías de control y se radicaliza la normativa -nacional y supranacional-que avala el registro permanente a la ciudadanía.
Nuestra investigación pretende dar a conocer, tanto los puntos de encuentro, como las discrepancias existentes en un conjunto de creaciones sumamente diverso y plural. En ellas se difunden nuevos aspectos culturales, políticos y estéticos de las disciplinas de supervisión tecnológica.
A través de investigación pretendemos mostrar cómo los nuevos paradigmas tecnófilos han repercutido en la creación digital del nuevo siglo, estudiando y relacionando diversos factores: no podemos limitarnos a enumerar o a describir un tipo de obras tan específicas que inevitablemente han de asociarse con acontecimientos producidos en el entorno donde se desarrollan. Para llevar a cabo una investigación organizada hemos dividido el trabajo en tres grandes bloques que finalizan con las Conclusiones de la misma:
1. Un recorrido inicial sobre la contextualización histórica, el origen e inicio de las primeras prácticas de control tecnológico.
2. Un recorrido histórico sobre el desarrollo y evolución de tendencias y proyectos artísticos concretos sobre vigilancia tecnificada en media art. Se divide en apartados sobre las tácticas (y sistemas) de control principal abordadas, teniendo en cuenta su correlación con determinados hechos tecnológicos, políticos y sociales.
3. En la tercera se propone el estudio de las líneas de trabajo más habituales de las prácticas artísticas entre 2001 a 2010, teniendo en cuenta las actitudes y posiciones más frecuentes con las que han sido concebidas la mayoría de las piezas estudiadas.The objective of Digital Artistic Practices and Control and Surveillance Technologies (2001-2010) is the analysis of the massive use of recording and surveillance technologies by the state and private companies along with its evolution in the field of new media art and in particular that of digital creations of the first decade of this century (2001- 2010). The specific objectives are: • To investigate the origins and evolution of control and surveillance technologies in depth to discover the background of digital artwork developed during the first decade of the 21st century. • To study the real causes of the evolution of technical surveillance in order to establish the cause-effect of the creations selected. • To consider to what extent the supposed democratisation of technologies has led to truly innovative and outstanding proposals as far as digital creation is concerned. • To propose new creative paradigms and characterise these types of digital practices. The investigation uncovers how digital artistic practices related to technical control and surveillance developed between 2001-2010 have evolved in line with technological, political and social transformations. This thesis contributes to organising and strengthening the study, within History of Art, of artistic practices centred on offering new viewpoints of how the individual is continuously confronted by technical registers belonging to the authorities.
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KAZANCIGIL, MUSTAFA ASIM. „A study of data processing in Xlet-based Interactive Digital Television Applications“. Doctoral thesis, Università degli Studi di Milano, 2013. http://hdl.handle.net/2434/217572.
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The main goal of this dissertation is to study the Xlet-based interactive applications (such as advertisements, games, government services and early warning applications) in the digital television broadcasting environment and to improve their versatility, usability and interoperability through the simplification of their codes and content management methods. The EU had set an obligation for its member states to begin digital television broadcasting by 2012, therefore the development of such systems prior to this deadline had become a task of utmost importance in recent years. At present, there are two major systems of digital video broadcasting (DVB), which are DVB-HTML and DVB-J (DVB-Java). I decided to give more emphasis on DVB-J for my research, mainly because it’s more compatible with the interactive applications that are created with Java-based Xlets, and also because it’s easier to use, modify and update; hence the reason why DVB-J is the system that’s preferred by a larger number of television broadcasting corporations worldwide. DVB-J is also the digital video broadcasting standard that’s compatible with a larger number of MHP (Multimedia Home Platform, or DVB-MHP) systems that are utilized by the set-top-boxes for receiving interactive content (in the form of Xlets) during digital television broadcasts; as well as by handheld devices and web-based internet television networks. As of today, Italy (which has a large and expanding DVB-T network) is one of the leading countries in the world that extensively utilize DVB-MHP systems for sending and receiving interactive content during IDTV broadcasts. By 2009, several administrative regions in Italy had already completed the switch-off process of their analog broadcasting systems and had gone all-digital. Numerous interactive services are currently available in the IDTV broadcasting environment of Italy, ranging from IDTV-commerce and IDTV-government services to the use of a growing number of internet content. At present, the terrestrial antennas for sending the aerial digital signals of the DVB-T networks aren’t capable of receiving any return signals for interaction by mobile handsets like the DVB-H, therefore interactivity is currently limited to internet connection through DSL in stationary devices or to mobile telephone services in the outdoor environments. Internet connection, however, allows the interoperability between different types of stationary and mobile devices, such as television sets, PCs, notebook computers, mobile phones, DVB-H, BlackBerry and iPod. Due to the complexities which arise from the burden of having to provide an efficient and safe interoperability between an ever-increasing number of different device types, I based my research on developing a CMS that’s simple, flexible and easy to upgrade. Since Xlets are Java applets that are developed for digital television broadcasting, I have so far concentrated on the utilization of Java TV API in platforms that are capable of receiving digital and interactive content, such as TV set-top-boxes, DVB-H, and the latest generation of cell phones. In order to optimize the use of such digital and interactive content, which become more diffused and complex through constant innovations, it is necessary to develop an IESG (Integrated Electronic Service Guide) system, due to the ever-increasing traffic of digital and interactive content. The IESG is particularly effective in categorizing the contents and optimizing their availability to the users through a more sensitive search which yields better results, thus saving both bandwidth and user time. In the following chapters, I have explained the methods that I used for the creation of simple and quick (optimized in terms of downloading and running time) Xlets for the IDTV broadcasting environment; and the elaboration of a basic and versatile content management system to store and run these Xlet-based applications by a Set-Top-Box, the functions and properties of which are emulated by the XleTView software. The themes that I chose for the Xlets are the Earthquake and Tsunami Early Warning application, the Recent Seismic Activity Report application, and the Emergency Services application.
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Lai, Yen-Cheng, und 賴彥丞. „A Study on UMTS Multimedia Broadcasting Multicasting Service“. Thesis, 2008. http://ndltd.ncl.edu.tw/handle/44194244712002082065.
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博士國立臺灣大學
資訊工程學研究所
96
The multicasting technique (one-source-many-destination) is widely utilized for multimedia content delivery in the Internet. In the recent years, mobile telecommunication networks have been integrated with the Internet. The Third Generation Partnership Project (3GPP) working group proposed the Multimedia Broadcast Multicast Service (MBMS) for multicasting multimedia content over the Universal Mobile Telecommunications System (UMTS). The standards for the UMTS MBMS service are currently under process. It is allowed rooms to enhance the current mechanisms proposed in the UMTS MBMS specifications so that better QoS and performance for the MBMS service can be achieved in the UMTS network. This dissertation focuses on proposing more intelligent mechanisms to make the MBMS service deployed more efficiently in UMTS. We consider the following two important issues for performance enhancement for the UMTS MBMS service. Radio Resource Management. 3GPP 23.246 defines the MBMS to deliver multicasting content over the Universal Mobile Telecommunications System (UMTS), where the common logical channel may be enabled to serve multiple MBMS users at the same time. However, the usage of the common logical channel may cause interference to the dedicated logical channels serving the traditional calls. To more efficiently utilize the radio resource to serve both traditional and MBMS calls, this dissertation proposes two channel allocation algorithms: Reserved Resource for Multicasting (RRM) and Unreserved Resource for Multicasting (URM). We develop analytic and simulation models to investigate the performance for the two algorithms, including the call incompletion probability and customers'' satisfaction indication. Our study indicates that URM outperforms RRM in terms of the call incompletion probability for the traditional calls and satisfaction indication by slightly degrading the performance of MBMS calls. File Repair Mechanism. During the MBMS content transmission, the data may be lost. Three file repair schemes were proposed in 3GPP 26.346 to retransmit the corrupted MBMS data. However, these schemes may introduce extra data traffic or signaling overheads. This dissertation proposes the Reuse Bearer Service (RBS) file repair scheme to resolve this issue. We analyze the four file repair schemes by analytical models and simulation experiments. Our study shows that the proposed RBS scheme may significantly outperform the previously proposed schemes.
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Tseng, Sheng-Yuan, und 曾生元. „Evolutionary Algorithms for Multimedia Broadcasting on Overlay Networks“. Thesis, 2006. http://ndltd.ncl.edu.tw/handle/18619452952310508733.
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博士國立成功大學
工程科學系碩博士班
95
With the development of the Internet, many new applications, like video conference, distance learning, network games and so on, need group communication services and require QoS guarantee from underlying networks. In contrast to many one-to-one unicast to support group communication, multicast is an efficient transmission mechanism, because multicast sends packets to the receivers along a transmission tree and replicates packets only at the branching points. This makes applications more scalable and leads to more efficient use of network resources. Currently, most multicast protocols are developed from IP-layer. However, IP-layer multicast protocols that function multicast on the network layer leave many unsolved problems that hinder the deployment of IP-layer multicast. Therefore recent studies have implemented such applications by application layer multicasting through organizing the multicast group in a peer-to-peer overlay network. This enables faster deployment of multicast services and adds flexibility to the service infrastructure. Moreover, the IP-layer multicasting problem in the Internet is transformed to the application-layer broadcasting problem in the overlay multicast network. On the other hand, many of the group applications have the QoS requirements, which limit the transmission time and the number of receivers to which each node can transmit, because data arriving later than a deadline are simply useless and the required bandwidth might excess the maximum link-bandwidth if the number of receivers is too high. Such a communication scheme in an overlay network can be regarded as a degree- and-delay constrained minimum-cost broadcasting problem, and appears to be NP-complete. This study proposes a novel genetic algorithm and an ant-based algorithm for resolving this difficult broadcasting problem and, then, compares them with some state-of-the-art methods. Simulation results with a series of problems demonstrate the efficiency and effectiveness of the proposed algorithms.
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Lai, Yen-Cheng. „A Study on UMTS Multimedia Broadcasting Multicasting Service“. 2008. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0001-2706200816021500.
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Wu, Chih-Jen, und 吳致仁. „Seamless Channel Transition for Heterogeneous Multimedia on Demand Broadcasting Schemes“. Thesis, 2011. http://ndltd.ncl.edu.tw/handle/19419166244087239449.
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博士國立臺灣科技大學
資訊管理系
99
With the accelerated growth of internet bandwidth and advances in multimedia technology, video-on-demand (VOD) services are growing in popularity. To achieve the VOD system, the simplest way is to assign a dedicated channel to each client and allow the client having a complete control over the video session. However, such a system places significant loads on server bandwidth resources due to the transmission of sizable data. To relieve the stress of the high demand on bandwidth, solutions based on broadcasting schemes are possible alternatives to the true VOD scheme. Many broadcasting schemes proposed so far try to reduce either clients’ startup latency or buffering space. However, due to the reason that the popularity of a video usually changes with time and clients might employ heterogeneous terminals with different communication capabilities, we focus on broadcasting schemes that not only allow service provider to adjust bandwidth allocated to one single video according to its popularity dynamically and seamlessly but also allow clients to choose among a range of bandwidths to download a video at the cost of their startup latency. In this dissertation, we first propose a heterogeneous broadcasting scheme and its seamless channel transition protocols. The scheme, called the multiple-base Broad- Catch scheme (MBC), is designed by modifying the BroadCatch scheme [61] to allow an arbitrary number of base channels defined in BroadCatch. Compared with the BroadCatch scheme, the MBC scheme has zero heterogeneous scalability when channel transition is performed. With zero heterogeneous scalability, new clients can benefit from newly added server channels without paying any extra cost. As compared with BroadCatch, our results show that MBC greatly reduces startup laten- I cies for low-end clients while slightly sacrifices those for high-end clients. Maximum buffering requirement is greatly reduced as well. Moreover, given a set of popular videos, we present a channel allocation policy which allows the service provider to be capable of determining the number of channels assigned to each video according to the popularity of all videos so as to make the most benefit from the broadcasting service. Secondly, we provide a thorough analysis of the heterogeneous behavior of the Fast broadcasting and receiving scheme (abbreviated as FBR scheme). Through a derived analytical formula, we deduce client bandwidth requirement for any given time slot, worst startup latencies for all heterogeneous clients, and average client bandwidth requirement together with heterogeneous scalability. Moreover, we propose a generalized FBR scheme called the GFBR-x scheme which is derived from the FBR scheme by keeping the number of segments broadcast on the last x+1 channels to be the same. Performances among the FBR, GFBR-2, and BroadCatch schemes are also evaluated. First, as compared with the BroadCatch scheme, the GFBR-2 scheme not only reduces startup latencies by around 25% s 50% for most low-end clients but also provides relatively acceptable startup latencies for some high-end clients. Second, the FBR and GFBR schemes have a smaller heterogeneous
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LI, Hsin-Hsien, und 李信賢. „The Applied Management Construction Research of Digital Multimedia Archive - A Case of Medical and Sanitary Broadcasting“. Thesis, 2008. http://ndltd.ncl.edu.tw/handle/92930333736862840584.
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碩士大葉大學
資訊管理學系碩士在職專班
96
This research adopts the digital multimedia preservation application management model of “Changhua Christian Hospital” and takes the “National United University” as site to construct and research the communication of healthcare. This research takes the cost to integrate the concepts of “preservation”, “application”, “management”, and “constructing”; finally, it will construct a digital multimedia communication platform by the topic of healthcare communication. By the arrangement of time and assistance of advanced net monitor, the digital information about healthcare can communicate automatically through the digital TV. Thus, students’ perception to the information about healthcare will advance. This research expects it can provide reference for the constructing of multimedia preservation application management. It also expects it can reach the predictive result of the research purpose. According to the questionnaire survey result, the testees generally accepted the healthcare communication service provided by this system. We expand the prototype frame the “Changhua Christian Hospital” has finished and communicate it. By the questionnaire survey, we know the students can accept the service of this system. And this result matches the forecasting, as well as verifies the usability of the expanded communication of this research system.
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Hung, Chun-Jung, und 洪俊榮. „Software Design and Implementation of the DSM-CC Mechanism for Digital Video Broadcasting- Multimedia Home Platform (DVB/MHP)“. Thesis, 2006. http://ndltd.ncl.edu.tw/handle/52517355519690170030.
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碩士國立成功大學
資訊工程學系碩博士班
94
During the past years, the Digital Television Broadcast (DVB) standard has been developed rapidly and has also become one of the most popular Digital Television standards. The essential idea of DVB is to replace analog services with digital ones, while DVB2.0 contains a roadmap for the development of digital broadcasting technology. The purpose of DVB 2.0 is to build bridges to the world of computing and telecommunications. With the evolvements of multimedia and Internet techniques, DVB starts to develop interactive TV, of which the data comes from the data broadcasting of DVB. In order to handle the data of DVB data broadcasting, Digital Storage Media Control and Command (DSM-CC) specifications are then defined in DVB. In this thesis, we investigate the data decoding process within data broadcasting by designing and implementing the DSM-CC mechanism. Some issues that are ambiguously defined in the specification of DSM-CC, i.e., memory management, the relation of sections, module composition, content update, management of Service Domain and the problem of path, are clarified. In this thesis, the solutions for resolving the aforementioned issues are also proposed as the references of improving DVB specifications.
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BENACEM, Lucien. „Cooperative DVB-H: Raptor-Network Coding Protocols for Reliable and Energy Efficient Multimedia Communications“. Thesis, 2010. http://hdl.handle.net/1974/5955.
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Reliable and energy-efficient delivery of multimedia to mobile terminals in dynamic networks is a very challenging problem. In this thesis, we focus on a cooperative extension to the Digital Video Broadcasting – Handheld (DVB-H) standard, forming a cooperative broadcast network whereby terminal-to-terminal cooperation creates a distributed form of multi-input-multi-output (MIMO) that supplements existing fixed network infrastructure.
First, we develop a novel and computationally-efficient hierarchical Markov model that is able to accurately perform a cross-layer packet error mapping between the physical and transport layers of the DVB-H/IPDC (IP DataCast) protocol stack. We then construct a discrete-event simulator in MATLAB® that incorporates all of the necessary modules to conduct dynamic multiterminal network simulations. Next, the convergence of cooperative wireless communication, Raptor application layer forward error correction (AL-FEC) and Network Coding (NC) is examined. Originally proposed for broadcasting over the Internet, the application of Raptor codes to wireless cooperative communications networks has been limited to date, but they have been mandated for use in DVB-H. Network coding is used to reduce energy consumption by opportunistically recombining and rebroadcasting required combinations of packets. Two novel coding-enabled cooperative relaying protocols are developed for multicast and multiple unicast file distribution scenarios that are transparent, fully distributed, and backwards compatible with today's systems. Our protocols are able to exploit several different forms of diversity inherent to modern wireless networks, including spatial diversity, radio interface diversity, and symbol diversity. Extensive simulations show that our protocols simultaneously achieve breakthroughs in network energy efficiency and reliability for different terminal classes and densities, allowing greatly improved user experiences.Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2010-08-03 19:45:54.943
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ANIS, Muhammad Moiz. „Retransmission coopérative de flux des données diffusion via les réseaux cellulaires“. Phd thesis, 2014. http://tel.archives-ouvertes.fr/tel-00978769.
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Among the multimedia content distribution services to the handheld receivers, mobile TV is a popular service. Digital Video Broadcast (DVB) networks have high capacity and coverage to perform a mass multimedia content distribution. The conventional DVB networks are designed to cover fixed receivers, which have a roof antenna. The handheld receivers have different configurations which cause weaker link budgets. Generally, a broadcast system is unidirectional and it does not have a feedback channel to ensure the reception of the data at the receiver side. On the other hand, cellular networks have more reliable bidirectional links with the handheld receivers. Individual multimedia transmission to each handheld receiver generates a huge load in the cellular networks. In the specific example of mobile TV, it is not efficient to regenerate the same transmission load for each handheld receiver. In our thesis work, we consider a cooperation between the broadcast systems and the cellular networks for an efficient multimedia reception at the handheld receivers. We use the cellular network link for the retransmission of the lost packets from a multimedia broadcast data-flow reception. In this work we analyze the coverage for handheld receivers in a single frequency broadcast network. We specifically consider several outdoor and indoor scenarios in a DVB-T2 network. We analyze how a data flow is processed in DVB-T2 and propose a scheme for the identification of packets in the DVB transmission. The core contribution of our thesis work is the proposition of a Real-time Flow Repair (RFR) Service based on cellular network, which repairs any multimedia data-flow to the handheld receivers in real-time. The proposed RFR service is based on a light client-server application protocol, namely Constrained Application Protocol (CoAP). The RFR proposal is also supported by the analysis of the load generated in LTE Radio access network due to RFR service.