介绍了直接数字频率合成源的基本原理及其一种专用芯片AD9854的功能特点，提出了利用可编辑逻辑器件(CPLD)控制AD9854产生基带线性调频信号的设计方案，并具体分析了CHD和AD9854产生调频信号的工作原理。最后给出了设计方案的测试结果。经实用达到了比较满意的效果。

The basic theory of direct digital syn th esis technology and the function of AD9854 are introduced, and a design of LFM c hirp signal generation using CPLD and AD9854 is put forward, then the principle of LFM chirp signal generation using CPLD and AD9854 is described in detail. At last, the experimental results of the design are given. The practical applicatio n achieves preferable effect.

TN958