Omap-based Ip Network Telephone System,

With the developments of VoIP (Voice over IP) technology, the IP network phone is growing up very quickly. Comparing to the traditional telephone, IP telephone has many advantages such as price, user requirement, multimedia session and so on. And all these advantages mentioned above will revolutionize telephone network and service.One of the main targets of this thesis is to design and implement IP network phone system based on 0Map5912. Firstly, this thesis introduces the advantages and developments of IP network phone system. Then, it briefly introduces the key technology and standard protocol according to the IP network phone system.Then, this thesis discusses the selection of OS platform, the software and hardware design of 0Map5912. The system structure of 0Map5912 which has dual-core processor (ARM+DSP), the work flow of the processor, the software design of DSP/BIOS for ARM&DSP inter-processor communication, the device driver for digital audio device, and the implementation of coding both at the ARM and DSP parts are introduced in detail.The emphasis of this thesis is the realization of SIP and RTP/RTCP protocols which are used for the IP network phone. This thesis firstly analyse the content and feature of SIP and RTP/RTCP protocols, and then introduces the transplantation of oSIP and JRTPLIB library in detail. The overall frame is put forward based on Reference Framework Level 6 (RF6), including the transmission, reception, and codec of audio.This thesis also makes an introduction of the algorithm used for audiocodec----G. 729, and through comparing with other aldio codec algorithms,the advantage of G. 729 is explained.Finally, there is a brief summary and some suggestions for further research.