介绍了DDS的基本原理，并给出了以DDS为基础的用于数字频率特性测试仪中的扫频信号源的设计与实现方法，该设计已通过实验验证并取得了良好的效果。
Abstract:
The basic principle of DDS is introduced, and the design and realizaTIon method for sweep singnal source in the digital frequency characterisTIc tesTIng instrument based on DDS are presented. Experiment has confirmed this design and shown good effects.
