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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Stereo Video Broadcasting Over Dvb-h

Bugdayci, Done 01 February 2012 (has links) (PDF)
This thesis proposes a complete framework of an end-to-end transmission of stereo video to mobile devices using DVB-H. Block diagram of the system is presented and operations conducted on the video at each layer are explained. Parameters and methodologies that may make a robust transmission possible are discussed. The transmission performance is analyzed in terms of error robustness under various coding methods, prediction structures, layering and protection strategies for different contents and channel conditions. It also investigates the effect of rate allocation between video quality and protection over robust transmission in erroneous environment. This works provides directive conclusions on the selection of the mentioned parameters and methods.
12

行動電視規範架構與營運模式之研究 / The study of mobile TV regulatory framework and business model

李駿, Lee, Jun Unknown Date (has links)
行動電視產業為無線電視產業、電信產業、內容產業、行動裝置製造產業等多方匯流共同合作下的結果。不同產業間合作前,可能產生不同業者在新產業中扮演的角色與定位、產業價值鏈/價值網之成形等問題。本研究研究目的在於了解國際間行動電視規範政策與管制議題,對於該國行動電視產業營運所產生的影響,以文獻分析方式選定日本、韓國、義大利與美國等行動電視市場較為成熟之國家分析其規範架構與營運模式之關係。並比較台灣、香港、新加坡政府提出之行動電視意見諮詢文件探討行動電視規範議題之制訂方向與業者回應。輔以深度訪談方法訪問我國主管機關與產業界對於行動電視業務開放之意見。最後依據台灣通訊傳播產業規範環境,由結構管制與內容管制兩方面討論行動電視產業規範架構之相關議題與未來可能之釋照方式,並提出其對應之營運模式發展建議。 針對上述研究問題,本研究主要結論如下: 1. 國際間行動電視執照類型包含:以營運平臺執照發放多頻電視平臺(MUX)執照,其執照內涵可包含頻率使用許可執照以及營運平臺經營許可執照;依傳輸服務經營內涵不同,分別發放「頻率執照」與「營運平臺執照」,前者發給廣播傳輸網路業者,僅能經營基礎傳輸業務;後者則為負責整合內容服務之營運平臺執照;而內容規範所需之執照,分為兩種規範方式:以傳統廣電法進行內容規範,或是參考歐盟視聽媒體服務,對於線性頻道節目採用較嚴格的廣電法管制,而非線性的隨選節目內容以低度管制進行規範。 2. 國際間行動電視營運模式發展同時會受到釋照方式不同所影響,釋照方式包含:審議、審議加競價、多回合競價方式。若以審議方式發給特定業者,行動電視營運模式將由特定業者主導,但需遵守較多義務規範;若以審議加競價方式釋照,可能將由廣電業者與電信業者共同經營行動電視服務。或是完全以競價方式拍賣頻率執照,其執照使用方式則最具彈性。 3. 在目前法律架構下,本研究建議行動電視適合以電信法開放,對於外資限制頻率租賃有較寬鬆規定。並鼓勵鼓勵廣電業者與電信業者合資組成團隊取得頻率執照,廣電業者擁有廣播傳輸網路以及內容產製能力,而電信業者同時擁有基礎網路以及與設備製造商議價之優勢,並且擁有龐大基本顧客群。並且建議行動電視市場發展初期,行動電視服務宜以其他電信服務搭售或以綑綁服務方式提供,以增加消費者使用黏度,並擴大市場規模,普及終端收視裝置市場。內容規範方面則建議採低度管制方式,頻道式節目內容以廣電法規進行管理,其他節目則按一般法律進行管理。 / Mobile TV is a newly converged service of television broadcasts, telecommunication services, and information technologies. Challenges arise from regulating the rapidly transformed technologies and proposing a suitable business model into a converging industry. The study aimed to examine different regulatory frameworks established in advanced mobile TV markets, and to categorize business models of mobile TV developed in those markets by reviewing government documentations, industrial research reports and conferences papers. In addition, the study interviewed key persons, including regulators, mobile TV trial team members and specialists, in mobile TV industries. Furthermore the study had made a comparison analysis of different mobile TV regulatory framework proposed by governments of Taiwan, Hong Kong, and Singapore. The study concluded that the mobile TV regulatory framework was architected by different regulatory approaches, including institutions which affect the content production, and institutions which had power on regulating stakeholders of media and telecom companies. The horizontal regulatory framework which included network layer, platform layer and content layer was mostly adopted by European countries in the converged age while regulating the newly risen mobile TV industry. The multiplex license could be treated as a network license and a platform operation license, and in other cases, the multiplex license was just the network license for the network operator. Some regulators extended existing digital terrestrial TV rules to mobile TV. As for the content regulation, regulators were taking light touch in regulating content, and adopting the Audiovisual Media Services Directive (AVMS) proposed by EU. AVMS had reduced the regulatory burdens for all audiovisual media services, and also modernized the rules on television advertising and product placement. The study suggested that the mobile TV in Taiwan was suitable to be regulated by Telecommunication Law, since Telecommunication Law had less restriction on the structure of stakeholders and foreign investments. Broadcasters and Telecommunication operators were suggested to joint as a new company to operate mobile TV service, since broadcasters, who were talented in content production, had broadcast network to transmit services to users; telecommunication operators, who were good at pricing, could use their advantages to set up bundling service to attract user in the nascent market.
13

IP Multicasting over DVB-T/T2/H and eMBMS using PARPS : Effect of the number of transmitters

Voladri, Ranjith Reddy January 2013 (has links)
With the advancement in the current wireless technology standards such as terrestrial digital video broadcasting systems (DVB-T, DVB-T2, and DVB-H) and the massive usage of the Internet over mobile devices, streaming of television channels in smart phones has become a necessary advancement for mobile users. As, UMTS dominating the entire mobile market globally and with the evolution of LTE, several mobile operators are working on an MBMS framework which will help to launch mobile TV services on respective operators. This paper deals with terrestrial and mobile TV with IP multicasting and broadcasting and is aimed to improve system spectral efficiency.  With the help of IP multicasting, the base station can be able to provide with significantly less spectrum by saving it from the channels which the user is not viewing currently. This case is analysed from several sets, called schemes of resource plan sets. The transmitter scheduling is dealt with by means of a Packet and Resource Plan Scheduling (PARPS) algorithm, and the simulated results are plotted in Matlab which assists in analysing the efficiency in the spectrum management and the coverage probability for the number of transmitters used for each scheme. The schemes are simulated in Matlab for different number of transmitters (2-7) in both the static and random model. The SFN schemes are offering greater coverage probability than MFN schemes, in all cases. Multicasting over Continuous Transmission Dynamic Single Frequency Network (CT-DSFN) offers a 1342% and 582% gain in Multi-user System Spectral Efficiency (MSSE) for 7 transmitters, from Broadcasting over MFN and Broadcasting over SFN respectively.  For 7 transmitters, Multicasting over CT-DSFN offers a 1213% and 428% gain in System Spectral Efficiency (SSE) from Broadcasting over MFN and Broadcasting over SFN respectively.
14

Simulace přenosu DVB-H a DVB-SH / Simulation of the DVB-H and DVB-SH Transmission

Arvai, Luboš January 2011 (has links)
The paper deals with the channel coding and modulation in DVB-H and DVB-SH and with the simulation of the components in MATLAB. In the case of DVB-H the document also discuss the influence of different types of transmission channels on the transmission process. The first part of this work describes the channel coding and inner modulation in DVB-H and DVB-SH. The next part describes applications created in MATLAB for settings and simulation of the transmission in the standards DVB-H and DVB-SH. The last part of this document graphically presents selected results of the simulation of the transmission and discuss them.
15

Cooperative DVB-H: Raptor-Network Coding Protocols for Reliable and Energy Efficient Multimedia Communications

BENACEM, Lucien 05 August 2010 (has links)
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
16

COST EFFICIENT PROVISIONING OF MASS MOBILE MULTIMEDIA SERVICES IN HYBRID CELLULAR AND BROADCASTING SYSTEMS

Gómez Barquero, David 18 January 2010 (has links)
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 / Palancia
17

Analýza a modelování přenosu signálu ve standardech DVB-H/SH / Analysis and Simulation of the Signals Transmission in the DVB-H/SH Standards

Polák, Ladislav January 2013 (has links)
Tato disertační práce se zabývá analýzou, simulací a měřením zpracování a přenosu signálů digitální televize pro příjem mobilního TV vysílání ve standardech DVB-H a DVB-SH. Tyto standardy vycházejí z předpokladu, že příjem signálu je charakterizován modely přenosových kanálů s vícecestným šířením. Tyto, tzv. únikové kanály, jsou charakterizovány hlavně zpožděním a ziskem jednotlivých cest. V závislosti na dalších parametrech (rychlost přijímače, Dopplerovské spektrum), je možné rozdělit únikové kanály do třech hlavních skupin: mobilní, přenosné a fixní. Dá se předpokládat, že v různých modelech kanálů bude přenášený signál různě ovlivněn. Proto je potřebné najít optimální parametry systémů (DVB-H/SH) pro kvalitní příjem vysílaných služeb mobilní televize, což je hlavním cílem této disertační práci. Pro tento účel byly vytvořeny dvě vhodné aplikace (jedna pro DVB-H a jedna pro DVB-SH) s GUI v prostředí MATLAB, které umožňují simulovat a analyzovat míru zkreslení signálu v případě mobilních, přenosných a fixních scénářů přenosu. Navíc, tyto aplikace obsahují i druhý samostatný simulátor pro nastavení a modifikaci parametrů jednotlivých přenosových cest. Díky tomu je možné zhodnotit vliv parametrů celého systému a kanálových modelů na dosaženou chybovost (BER a MER) a kvalitu přenosu. Ve všech přenosových scénářích (v závislosti na poměru C/N) byly získané, vyhodnocené a diskutované zkreslení signálů. Navíc, u standardu DVB-H, všechny získané výsledky ze simulací byly ověřeny měřením. Rozdíly mezi dosaženými výsledky (simulace a měření) byly rovněž podrobeny diskuzi. Tuto disertační práci je možné rozdělit do čtyř hlavních částí. První část disertační práce se zabývá rešerší současného vývoje v oblasti digitálního televizního vysílání na mobilní terminály ve standardech DVB-H/SH. Na konci této části jsou jasně popsány cíle této disertační práce. Druhá část práce je zaměřená na stručný popis blokového diagramu vysílačů v obou standardech DVB-H/SH. Dále jsou stručně popsány modely přenosových kanálů, které se používají pro modelování přenosu signálu. Stručný popis vytvořených aplikací, i s vývojovým diagramem, které jsou vhodné pro simulaci a analýzu přenosu v DVB-H/SH, jsou popsány v třetí části práce. Čtvrtá a nejdelší část této disertační práce se zabývá vyhodnocením získaných výsledků ze simulací a měření.

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