Performance of scalable video coding for a TV broadcast network with constant video quality and heterogeneous receivers

Video broadcasters currently envision to target a variety of receiving devices of different resolutions. In such a heterogeneous TV network the transport resource consumption is likely to increase as the types and number of receiving devices increase. We estimate the required capacity for an IPTV and mobile TV network taking into account parameters as currently proposed in standardization bodies. The consumed transport capacity fluctuates over time for two reasons. First, as we target constant video quality as much as possible, the video is encoded in variable bit rate. In order to characterize the fluctuations of the bit rate associated with one channel we have encoded a representative set of video clips. Second, the user behavior causes the transport capacity demand to fluctuate because we consider a multicast-based transport system where only the requested channels are transported. We compare two modes for transporting TV channels in multiple resolutions: a mode based on the Scalable Video Coding (SVC) where all video resolutions are embedded in one stream and a simulcast (SIM) mode where all resolutions are offered in parallel. We evaluate in some realistic examples which of the two effects is dominant, i.e., the bit rate penalty of SVC or the fact that SIM transports the video streams in parallel rather than embedding them in one stream as SVC does

Redes de nova geração e o serviço universal de telecomunicações em Portugal

Doutoramento em Engenharia EletrónicaThis thesis addresses the issue of Universal Service for telecommunications in the context of the access networks of next generation. This work aims to contribute to the redefinition of the concept of universal telecommunications service focusing primarily on extending it to broadband services as economic and social development factor and taking into account the degree of dependence that currently, modern societies have for the different communication and information services. Complementarily it also intended to meet some of the challenges set out in the European 2020 agenda. Universal Service is defined here as access to a telecommunications network (with obligations in terms of type and quality of service for the operator), by of all citizens at any country's geographical location, with uniform and accessible price. The approach adopted is the State as a mentor for social equity, respectful of the liberalized market dynamics but also knowledgeable of the requirements of modern telecommunications services and its relationship with the different technologies available. The possibility of subsidizing is assumed. The Universal Service´s provision is subject to open to all operators, which are assumed to possess other profitability businesses, than the Universal Service, using technologies similar to those prescribed for the respective Universal Service provision contest. Although the work has components of economic and financial analysis, the approach is the engineering point of view, looking for help to identify technical and organizational solutions which offer prospects for the dissemination and adoption of next generation network solutions. As a point of departure the work gives an overview on the state of the art access networks , trying to identify which of the differences between this reality and possible scenarios for next-generation network with potential access to the generality of the people . The case of the Portuguese reality will be given special attention, taking into account their specific characteristics in terms of geography, demography, economics and market dynamics. The main results of this work are: • Identification of possible scenarios for the evolution of existing networks, in particular in areas with deficit coverage. • Identification of possible operating models and business to the materialization of the above scenarios developed and its economic analysis in an attempt to determine the critical factors associated with sustainability and / or need for subsidies. • Contribution to the regulatory framework of new generation networks from the point of view of the constraints of technology and the specifics of the Universal Service.Esta tese aborda a questão do serviço universal de telecomunicações no contexto das redes de acesso de nova geração. Este trabalho pretende contribuir para a redefinição do conceito de Serviço Universal de Telecomunicações concentrando-se principalmente em estendê-lo a serviços de banda larga como factor de desenvolvimento económico e social e tendo em conta o grau de dependência que, actualmente, as sociedades modernas têm em relação aos diferentes serviços de comunicação e informação. De forma complementar pretende-se também ir ao encontro de alguns dos desafios enunciados na Agenda Europeia 2020. Serviço Universal é aqui definido como o acesso a uma rede de telecomunicações (com obrigações em termos de tipo e qualidade de serviço para o operador), por parte de todos os cidadãos, em qualquer localização geográfica do país, a preços uniformes e acessíveis. A perspectiva adoptada é a Estatal como mentor da equidade social, respeitador das dinâmicas de mercado liberalizado mas também conhecedor dos requisitos dos modernos serviços de telecomunicações e da sua relação com as diferentes tecnologias disponíveis. A possibilidade de subsidiação é assumida. A prestação de Serviço Universal é sujeita a concurso aberto a todos os operadores, que se assume possuírem outros negócios, que não apenas o Serviço Universal, com rentabilidade e usando tecnologias semelhantes às preconizadas para a respectiva prestação de Serviço Universal. Embora o trabalho desenvolvido tenha componentes de análise económico-financeira, a abordagem utilizada é a de engenharia, procurando contribuir para a identificação de soluções técnicas e organizacionais que possam oferecer perspectivas sustentáveis para a disseminação e adopção das soluções redes de nova geração. Como ponto de partida o trabalho apresenta uma visão geral sobre o estado da arte das redes de acesso, procurando identificar quais os diferenciais existentes entre essa realidade e a de possíveis cenários de rede de próxima geração com potencial de acesso para a generalidade dos cidadãos. O caso da realidade Portuguesa será objecto de uma atenção especial, tendo em consideração as suas especificidades em termos de geografia, demografia, economia e dinâmicas do mercado. Os principais resultados deste trabalho são os seguintes: • Identificação de possíveis cenários para a evolução das redes actuais, nomeadamente em áreas com deficit de cobertura de rede. • Identificação de possíveis modelos de operação e negócio para a materialização dos cenários acima desenvolvidos e respectiva análise económica, como tentativa de determinar os factores críticos associados à sua sustentabilidade e /ou necessidade de subsidiação. • Contributo para o quadro regulatório das Redes de Nova Geração sob o ponto de vista dos constrangimentos das tecnologias e das especificidades do Serviço Universal

Transmission of variable bit rate video over an Orwell ring

Asynchronous Transfer Mode (ATM) is fast emerging as the preferred information transfer technique for future Broadband Integrated Services Digital Networks (BISON), offering the advantages of both the simplicity of time division circuit switched techniques and the flexibility of packet switched techniques. ATM networks with their inherent rate flexibility offer new opportunities for the efficient transmission of real time Variable Bit Rate (VBR) services over such networks. Since most services are VBR in nature when efficiently coded, this could in turn lead to a more efficient utilisation of network resources through statistical multiplexing. Video communication is typical of such a service and could benefit significantly if supported with VBR video over ATM networks. [Continues.

The planning and optimisation of DVB-H radio network

In the DVB-H (Digital Video Broadcasting - Handheld) radio network planning, there are details that lack final consensus in the scientific field. The aim of this doctoral dissertation is to investigate advanced DVB-H radio network planning and optimisation. This dissertation presents the results of measurement techniques, network coverage and quality estimation, technological and economical optimisation, as well as error correction and single frequency network performance. The outcome includes proposed DVB-H radio network planning and optimisation methods that can be applied to the further investigation of detailed parameters in the radio link budget. There are also case studies that show the functionality of the presented methods with typical performance values. Based on comparative investigations, a process chart was created for DVB-H radio network planning and optimisation. The process blocks can be applied in a typical DVB-H network deployment, for the initial high-level phase as well as in the detailed network planning and optimisation phase. Using this process, the most relevant items were selected for in-depth studies. The investigations are presented in the annexed publications. The reminder was revised by comparative literature studies. The structure of the thesis follows the designed process charts. The main focus of this dissertation is the development of DVB-H radio network planning methodologies. One of the goals was to investigate the radio interface measurements, their post-processing and analysis. This can provide a guide to the selection of the appropriate values as a function of the radio channel type. An additional goal is the controlled management of over-sized single frequency network areas through the balancing of elevated SFN interference levels and related SFN gains. The development of a radio path loss simulator is the basis for these studies. The case results are presented as a function of the relevant radio parameter values, transmitter power levels and site antenna heights, both in theoretical and realistic network layouts. In addition to these topics, this document also investigates selected electro-magnetic compatibility, human exposure safety zones and radio coverage estimations. Also the balancing of technical radio parameters and network costs in order to complete the planning process steps is covered