摘要
VOIP是实现在IP网络上实时传输语音的系统。在深入研究开源SIP协议栈的基础上,设计了一个基于ARM920T内核的嵌入式语音终端。为了实现实时双向的语音通信,修改音频处理芯片的底层驱动,将音频输入输出用两个描述符表示,并对应用程序做了相应修改。同时,提出了通过动态释放端口的方法,提高系统资源的利用率。测试表明:在局域网中,可实现两个终端及终端与计算机间的语音通话,且延迟小,丢包率低,系统资源的利用率高。
VOIP is a voice system that implements real-time transmission of voice signals in IP network. Based on an open-source SIP stack, an embedded voice terminal with a core of ARM920T micro-processor is designed. In order to implement the real-time bidirectional voice communication, the bottom chip drives of the audio processor are modified and the audio input and output denoted with two descriptors, and the corresponding application programs also changed. In addition, a method for dynamically releasing port and increasing utilization efficiency of the system resources is proposed. Experiment indicates that the voice calls of between two terminals or between a computer and a terminal could be realized, with small delay, low packet-loss rate and high utilization of system resources in a local area network.
出处
《通信技术》
2016年第9期1255-1259,共5页
Communications Technology
