Abstract: This paper presents a VoIP ATA solution based on a single digital signal processor (DSP). DSPs are suitable for arithmetic-intensive application and unsuitable for control-intensive application because of the limitation of I/O and memory resources. This solution is based on a 16-bit fixed-point DSP and μC/OS-II embedded real-time operating system. It makes good use of the limited resources, supports SIP and TCP-UDP/IP protocol. It can connect the analog telephone to Internet and realize the VoIP application. This system has a great future for its high efficiency and low cost.

Key words: Analog telephone adapter (ATA), Voice over Internet protocol (VoIP), Digital signal processor (DSP), μC/OS-II

摘要： 提出和实现了一种新颖的基于单个通用数字信号处理器(DSP)的VoIP模拟电话适配器方案。DSP的I/O和存储资源非常有限，通常适于运算密集型应用，不适宜控制密集型应用[5]。该系统高效利用单DSP的I/O和片内外存储器资源，采用μC/OS-II嵌入式实时操作系统，支持SIP和TCP-UDP/IP协议，通过LAN或者宽带接入，使普通电话机成为Internet终端，实现IP电话。该系统软硬件结构紧凑高效，运行稳定，成本低，具有广阔的应用前景。

关键词: 模拟电话适配器, IP电话, 数字信号处理器, μC/OS-II