基于分相存储和多DAC伪插值的高速波形合成方法

A method of generating arbitrary waveform based on data storage with different phases and pseudo interleaving of multiple DACs

DDS(直接数字合成)技术被广泛应用于任意波形信号的产生,但由于受RAM和DAC器件工作速度的限制,制约了输出波形频率的提高。本文针对高速任意波形发生器的设计与实现,提出了一种通过分相存储和并串转换以解决RAM速度限制、通过多路DAC并行伪插值技术解决了DAC转换速率限制的高速波形合成方法,并讨论了两种方法的综合应用,给出了采样频率2GSPS的任意波形发生器的原理方案。最后通过500MSPS任意波形合成实验,验证了该方法的有效性和工程应用价值。

DDS （direct digital frequency synthesis） is a digital technique about frequency synthesis which was widely applied in arbitrary waveform generator （AWG）. With the development of it, the output frequency of DDS is limited by the operation rate of RAM and the convert rate of digital to analog converter （DAC）. Aimed at the design and realization of high speed arbitrary waveform generator, a method of generating arbitrary waveform is put forward in this paper, which conquered the operation rate limitation of RAM based on Data Storage with Different Phases and break through the limitation of DAC convert rate by pseudo interleaving of multiple DACs. At last, the application of re- searching AWG with sampling rate 500 MSPS based on data storage with different phases and pseudo interleaving of multiple DACs is introduced and spectrum of output is presented, the results showed that the method is reliable.