Embedded Voice/Data Transmission System Design

Today, Internet has become popular facility to get information from modern society. With the descend of hardware price, high performance MPU is more and more used in embedded system, which make it possible to access to the Internet. If the embedded system is connected to the Internet, the information can be transmitted to every corner around the world. It is predicted that the combination of the embedded system and the TCP/IP is an important direction of modern embedded technology.Through TCP/IP, every embedded system can get a unique IP address in the world, and connected with other network system. But the traditional TCP/IP is too complex that it is difficult to implement TCP/IP in a lot of low-grade MPU. So, the high performance MPU can be used as the embedded system "Engine" to upgrade the hardware. In the other hand, the traditional TCP/IP was cut down on the request of the embedded system, and fewer hardware resources were occupied in the system.In this project, several different voice data compress algorithmic and their application were firstly analyzed and the Advanced Multi-Band Excitation (AMBE) voice data compression technology was selected. Then some other existing embedded system was discussed. At last, a very useful embedded voice/data transmission system was designed. The whole system designed in this project contains two parts: a TCP/IP embedded 80386 network model and a voice board as the remote client, a PC with network adaptor as the server. The voice signal was transmit from the voice board to the 386 network model, and compressed by AMBEvoice data compression software algorithm, then it was sent to the remote PC through the Internet and wireless data transmission equipment PTR2000. At the same time, control information and voice data can be transmitted from PC to 386 network model in the same way.The embedded voice/data transmission system designed in this project can choose Internet channel or wireless channel in different environment. In wireless mode, it is different from the public mobile communication network. The spread spectrum technology, channel coding/decoding technology and error controlling technology are deployed in this system. Voice/data can be transmitted in high speed mobile environment by this system. This system has advantage such as wide over cast, high secrecy, high flexible, strong anti-jamming, high sensitivity, high reliable. This system also can be used by 119, 122 etc.