Based On The Research And Implementation Of Haisi Hi3110e Set-top Boxes Of Voip

With the development of the technology of television, the digital signal has been substituting for the traditional analog signal in people’s daily life. The set-top box of digital TV is widely used, but the traditional set-top box can only realize unidirectional digital television broadcast, which cannot fulfill people’s need.The period of tri-networks integration is coming, which makes the across-network transmission of video, audio and data transmission not far away. It is possible that the mobile equipment, the computer and the television can communicate with each other. The bidirectional network brings the set-top box of digital TV great chances, and the set-top box is developed to be a high clear, interaction, intelligence and multi-function platform. The audio based on the network is a hot spot in these years. VoIP based on set-top box is the inevitable product of tri-network integration.The VoIP system is mainly compased by two parts:the server and user agent. The application of VoIP based on set-top box is considered as a user agent, which uses the SIP signaling protocol to establish a conversation, and controls the signaling through the model of transaction state machines. It also applies the SDP to negotiate the attribute of conversation, and chooses the u-law G711codec algorithm to compress the voice data. At the same time, the VoIP transmits the voice data through RTP, feeds back the quality of the real-time voice transmission with RTCP.Firstly, the paper introduces the status and trends of digital TV and VoIP, the development of tri-networks integration is also presented. Secondly, the key technology of VoIP is described. The network model of SIP, message type, message mechanism and call model are analysised. The structure of SDP is described. And, the paper gives an overview of the hardware framework and software structure of haisi Hi3110E. Thirdly, a VoIP application is designed based on the STB of haisi Hi3110E. According to the designment, the module division of the software is described, and the module implementation of the software is explained in detail. The system, which can build the end-to-end conversation between the computer and the set-top box, is realized. In addition, the function tests of the VoIP are carried out in this paper, incuding the registration and the calling of VoIP. The factors which influence the quality of the voice are analyzed. The result of the tests show that the application of VoIP based on the STB of haisi Hi3110E can achieve the registration and calling control. And the quality of real-time voice is good, the delay is short. This system has achieved the anticipate target.