一种数字频率合成器的FPGA实现技术*

直接数字频率合成器(DDS)技术是近四十年来发展起来的基于查找表的频率合成技术。作为信号发生器的一种,数字频率合成器是通信系统的重要组成部分,在很大程度上决定了通信系统的性能。介绍了DDS的基本原理,并实现了一个基于FPGA的DDS设计。通过改变查找表的存储数据灵活地改变输出的波形;根据频率分辨率的要求不同,修改具体波形数据值。其操作简单、频率分辨率较高、全数字化、便于集成,在工程应用上具有很大的使用价值。

Realization of direct digital frequency synthesizer based on FPGA

The technology of direct digital frequency synthesizer(DDS) is a technology of frequency synthesization based on look-up table,which was developed about forty years lately.As a kind of signal generator,DDS is an important part of communication system,deciding the performance of it in most degree.This paper introduced the fundamental of DDS and how to realize a DDS based on FPGA.If the waveform memory had been changed then the output wave type would be changed easily.It could be easily operated,had higher frequency separated ratio,was convenience to integrated as totally numeralization and this design was valuable in engineering application.