Technical Study Of Home Integrated Services Terminal

With the rapid development of computer, wideband network and IC technologies, multimedia communications become the development focus of world information network technology. Meanwhile, the popularization of digital TV has become urgent in china.HFC network is characteristic with broad bandwidth and rich network resources. Presently how to fully exploit its features has gained more and more attentions and studies.This paper firstly investigates STB's variety, architecture and its study status domestic and abroad. Then, On the basis of particular analysis about the DOCSIS and DVB-C protocols, the author lists the disadvantages of the STBs which are popular in the market now.These STBs utilize the telephone line to transmit upstream messages, which leads to the feature of narrow upstream bandwidth. This feature restricts the realization of wide-band multimedia integrated services and future development. Therefore it is required to develop a kind of Home Integrated Service Terminal with embedded cable modem, to realize high speed interaction of multimedia services. In this terminal ,the DVB-based front-end interactive module comprises a double-tuner and embedded cable modem.It can simultaneously receive DVB digital TV programs and the interaction of broadband multimedia services.Meanwhile the home terminal has variable interfaces,easy for expansion. This paper mainly focuses on the design of software and hardware architecture , high speed communication channel,and the research of the implementation technology of the multimedia integrated services. The paper also explains the methods to solve the technical problems, such as: the communication mechanism between Home Integrated Services Terminals and head devices, how to receive and show the DVB-C digital TV programs, how to deal with all kinds of multimedia data stream services,and so on. The hardware achitecture of Home Integrated Services Terminal is mainly composed of the following five parts: DVB-based front-end interactive module , video and audio data processing module, output presentation module, peripheral equipment data interface module, memory management module. As for the software implementation, we used the multiprocessing method in OS20 toestablish the system software procedure. Finally, this paper primary discusses the realization of the connection gateway and VOIP functions of terminal.The Home Integrated Services Terminal accords with the DVB-C and DOCSIS protocols, and can make full use of HFC network's advantages. Users can enjoy all the multimedia integrated services at home, such as: digital TV, VOD ,INTERNET, VOIP, data transmission, interactive games, and so on. Its developing, manufacturing and stepping into market will undoubtedly accelerate the growth of domestic tv-related industry , ASIC, chip manufaturing industry, embedded application software industry.