AD9857 是一款功能强大的可编程数字上变频器,高速的处理速度、精确的载波 频率和灵活的数字控制使得它广泛应用于通信、雷达、导航等各个领域。本文介绍了该上变频器的用法和功能,给出了与DSP 进行传输的接口连接和寄存器配置。结合软件无线电的思想,设计一个可以按照用户需要灵活更改载波频率和调制方式的双路音频无线传输系统。 关键字:AD9857;数字上变频器;独立边带;软件无线电 Abstract:AD9857 is a set of powerful programmable digital upconverter with so many advantages. It has a high speed of processing. The carrier frequency made from inside DDS core is very precise and it is also easier and flexible to control it in digital way. It is because of so many excellent qualities that AD9857 is widely used in different kinds of fields such as communication, radar, navigation and so on. This article makes an introduction of this chip’s usages and functions. The interface used to communicate with DSP and the setting of its inside registers are also included. With the idea of software radio, the design of a double-path audio wireless transmission system which is easy to change the carrier frequency and the mode of modulation is also given. Key words: AD9857; digital upconverter; ISB; Software Radio