摘要
杂散特性是影响直接数字频率合成器(DDS)应用和发展的主要因素之一.对理想DDS杂散的特性进行了分析,在此基础上给出了DDS杂散的来源,详细讨论了延时叠加、相位扰动等抑制杂散的方法.并采用相位扰动和延时叠加相结合的方法在FPGA上完成了DDS的设计,得到了理想的正弦波形,其波形平滑,频谱纯正,抑制效果良好.
Spurious performance is one of the main factors affecting the application of DDS. The spurious signals of DDS under ideal condition are analyzed in this paper, and on this basis the source of spurious is introduced. Methods used to reduce the spurious signals of DDS based on delay overlapping and phase dither is discussed. Finally a DDS is designed on a FPGA chip using the technology of delay overlapping and phase dither. A ideal sine waveform is achieved and its spurious signals are suppressed.
出处
《微电子学与计算机》
CSCD
北大核心
2009年第7期127-129,133,共4页
Microelectronics & Computer
基金
国家“八六三”计划项目(2006AA06Z105)
湖南省教育厅项目(08C615)
芙蓉学院教改项目(08jg06)
关键词
直接数字频率合成
杂散抑制
相位舍位
延时叠加
相位扰动
direct digital frequency synthesis
quantization noise
phase truncation
delay overlapping
phase dither
