一种基于DDS的快速跳频信号源系统设计

DDS是一种先进的直接数字式频率综合技术,具有精度高、变频速度快、控制灵活、实现方便等特点,在频率合成领域,它已经逐渐取代了传统的模拟式频率综合.本文介绍了一种基于DDS芯片AD9858的低杂散、低相噪、快速跳频的信号源设计方案,根据AD9858的主要特点和内部构造,详细研究了利用单片机与AD9858构成快速跳频源的技术方案.同时从整个单元的系统结构和功能模块方面介绍了该跳频源的具体实现方法,给出了单片机与AD9858之间的硬件接口图,并简单描述了系统的软件控制流程.通过实验验证了该设计方案的可行性.

Design of fast frequency step resource based on DDS

DDS is an advanced direct digital synthesis technology which has the feature like high frequency resolution, fast frequency switching speed, agile control, apt realization, etc. Now it gradually takes the place of traditional analog frequency synthesis in the field of frequency synthesis. A fast frequency step resource of low spurious and low phase noise based on AD9858 is presented here. The main feature and internal construct of AD9858-namely the high performance DDS chip-is introduced briefly. Detailed technical resolution on how to connect and design single-chip microcomputer and AD9858 to compose a fast frequency step resource is particularly conducted. Specific implementation method about systematic structure and function module also been demonstrated. The hardware interface between AD9858 and single-chip microcomputer is given while the controlling flow of system software is described in the paper as well. Experiments and tests indicated the feasibility Of the system.