| As the progress of economy and development of science and technology, the importance of information services in people's working and daily life grows quickly. The service of information expands from traditional narrowband operations such as telephone to broadband multimedia operations which integrate voice, high-speed data and moving video. To satisfy the requirement of development, the broadband multimedia network of service should be established to transmit multi-service at the same time. The author provides FTTX+Cable mode for broadband multimedia communication, and realizes the integrated system, front management platform and multi-network-interface terminal based on that network mode. The system has been used in practical environment. The author has done deeply research on access network, such as network based on Ethernet and FTTH. Combining with the current broadband multimedia service requirements, the author layouts the concept of octave transmission bandwidth after the entirely analysis to digital transmission. The most important character of digital transmission compared with analog transmission is the efficient use of frequency bandwidth. If the transmission band is controlled in octave transmission bandwidth, the modulation method of direct light intensity can be used to increase the distance of light transmission (over 150km), the method can reduce the design and vindication of system. In access networks, the actual problem to be resolved is the last one hundred meters, not the last 1km meters, since the optical node is closing subscribers. The last one hundred meters is usually passive, and could adopt kinds of medium such as fiber,cable,twisted pair,power line,wireless and so on. Because cable network has the highest rate of entering home, the utilization of cable resource is always the desire of CATV professional. In this thesis three schemes have been suggested to solve the problem of using wireless transmission technology (2.4GHz-2.4835GHz frequency band) in CATV network. Firstly, reducing the inherent frequency of modulator is recommended if the relational chips can be obtained; Secondly, using the scheme of low frequency conversion from outside; Thirdly, increasing the working frequency range(87MHz-2.5GHz) of passive apparatus . As a commercial broadband access platform, there is requirement in a perfect and entirely management platform beside a predominant hardware platform. In FTTX+Cable, the management system plays a very important role as the chief controller of whole network system. Based on UNIX and ORACLE database, the broadband multimedia commercial support platform provides individuation, society, information services and the whole system platform satisfies the requirement of future development and real-time disposing ability, all of these provides a colligated operations platform which provides broadband multimedia commercial services for users. The development of broadband multimedia services demands more abundant information resource. This thesis provides a quick, easy, low-cost software scheme of stream transform in relation to current most abundant VCD/DVD resource and most popular information transmission format (MPEG-TS stream) after the deep research on MPEG Encodee/Decoder. As the user terminal enters thousands of families, it should be low-cost, abundant functions, good adaptability and updatable. So the research on colligated services terminal of broadband access network is absolutely necessarily to development of the society's information. The thesis provides a scheme that integrates the advantage of CATV network and Ethernet network, and colligated services terminal to kinds of information operations, such as audio,video,data in TV sets. It realizes the multi-operations' dynamic process and presents in limited store memory by using application software's dynamic loading technology.
|
PDF Full Text Request