摘要
对直接数字频率合成器(DDS)的相位截断杂散、幅度量化杂散及非线性杂散的频谱特征和分布规律进行了定性分析,得到相位截断是DDS输出频谱杂散的主要来源.利用得到的结论提出了合理选择时钟频率的方法,用于抑制DDS输出信号中的相位截断杂散,然后探讨了DDS级联设计的方法,用于降低系统设计中DDS输出信号的杂散,最后进行了计算机仿真,证实了本文方法的可行性.
The spurious signals in DDS generated by phase-truncation,amplitude-truncation and the digital-to-analog conversions are analyzed,and their frequency spectra characters and distributing rules are studied.The conclusion presents phase truncation is the critical source of spurious signals spectrum in DDS.A new method selecting the clock frequency correctly is proposed.It is used to eliminate spur caused by phase truncation.Then the author presents a scheme of concatenation structure to reduce spurs of output ...
出处
《电子器件》
CAS
2007年第2期572-574,578,共4页
Chinese Journal of Electron Devices
关键词
直接数字频率合成
降低杂散
相位截断
级联
direct digital frequency synthesis
spurious signals reduction
phase-truncation
concatenation
