- 學位論文
手持設備數位視訊廣播技術規範與地面廣播系統兩立性之研究
The Research of DVB-H Technology Specification Compatibility with DVB-T System
摘要
手持設備數位視訊廣播（Digital Video Broadcasting-Handheld；DVB-H）係以數位電視地面廣播（Digital Video Broadcasting-Terrestrial；DVB-T）之標準為基礎，專用於手持式裝置的標準方案。有別於DVB-T系統，DVB-H額外增加「分時切片」（Time Slicing）技術，以克服數位電視應用於行動裝置之高耗電問題。DVB-H系統亦利用「多重協議封裝-前向糾錯」（Multi-Protocol Encapsulation-Forward Error Correction；MPE-FEC）編碼機制，以進一步提升手持式裝置的移動接收性能。為能確保行動應用時之服務不中斷，故有「軟式遞交轉移」（Soft Handover）之機制。此外，加入4K 傳輸模式（Mode）與深度（In-Depth）符號內間插之功能，明顯提升頻譜的使用效率，且為提升行動接收時的信號掃瞄與頻率交換，故加入傳輸信號命令參數（Transmission Parameter Signalling；TPS）載波命令，使系統能進行頻道編碼及調變相關的信號參數，以符合DVB-H系統所需的規格要求。 以往的大眾市場主要是單向廣播，但是隨著族群年齡層的明顯區分，日益分為無數個「分眾市場」。經由單一的大眾傳播媒體已經無法達到對大眾廣播的傳播效果。政府、傳播媒體與廣告界人士都希望能找到以最低成本且最精確地廣播方式將訊息傳達到目標收視戶，這正是手持設備數位視訊廣播的優勢所在。正因如此，手持式數位電視才會受到各界關注的目光。 本研究主要係針對手持式數位電視DVB-H之系統規格、相關技術與商業應用，進行分析與探討。綜合各項分析報告可知，未來的電視更是要重視服務，且服務內容應該有所區隔。也就是說，以市場機制為基礎進行改革，可以為無線廣播電視產業的未來發展，注入一個充滿生機和活力的環境。 本論文研究成果，除可提供無線廣播電視工程人員未來執行手機電視技術連結之參考依據，此外DVB-H傳輸服務網絡可做為各電視台無線廣播傳輸網絡規劃之規範依據，亦可提供廣大的手機設計製造商對手機電視發展之中介軟體，能有更深一層的了解與參考規範依據。
並列摘要
Digital Video Broadcasting-Handheld (DVB-H) is a standard solution used specifically for handheld devices and based on Digital Video Broadcasting-Terrestrial (DVB-T) standards. Different from DVB-T system, DVB-H adds Time Slicing technique to address the high power-consumption problem when digital TV is applied on mobile devices. DVB-H system also utilizes Multi-Protocol Encapsulation-Forward Error Correction (MPE-FEC) encoding scheme to further improve the mobile reception performance of handheld devices. Soft Handover scheme is provided as well to ensure the continuous service for mobile applications. Besides, adding the functions of 4K Mode and In-Depth Symbol Inner Interleaver has apparently increased the usage efficiency of the spectrum. To improve signal scanning and frequency switching of mobile reception, TPS carrier commands are added to let the system perform the channel encoding and to modulate the related signal parameters to comply with the required specifications of DVB-H systems. In the past, the mass market is primarily of unidirectional broadcasting. However with the distinct diversity between different social groups and ages, the mass market has divided into many “niche markets”. The broadcasting effect to the mass population can no longer be achieved by a single mass medium. People from the government, mass media, and advertisement all want to find a most low-cost and accurate way of broadcasting to transmit the messages to the target customers. Digital mobile TVs possess the desired low-cost and accurate characteristics and thus attract close attention from majorities of the public. In this research, we analyze and investigate system specifications, related technology and commercial applications of handheld digital TV DVB-H. As a summary of the analysis reports, future TV systems will have to pay more attention to services and provide distinct service contents. That is, innovation based on market mechanism can set up an environment full of vitality suitable for future development of wireless broadcasting TV industries. In addition, in this research we analyze the value of and the major problems faced by the mobile TV wireless broadcasting industries. We also propose several possible solutions with a hope to provide some tactic thoughts for the development of this new medium. This paper result of this research could be the useful reference which used by engineers who work in the radio and television fields. Moreover, DVB-H network service could be used as a sample blueprint when they design network system for each television and radio station. Actually this research result could be used broadly in other fields, such as cell phone middlewave technology. Cell phone manufactures can use the research result when they develop new cell phones which allow users to watch TV whenever they want.