关键词: 直接数字频率合成器, 带内杂散, AD9858

Abstract:

Direct digital frequency synthesis technology has important position in the field of frequency synthesis, but the connatural spur characteristic greatly limits its application development. In this paper, based on the analysis of working principle of the DDS and spurious noise source, we found that delta frequency tuning words change of direct digital frequency synthesizer chip can improve Spurious in band. Adopting a AD9858 chip as the core physical contrast test on the hardware platform, verify the delta frequency tuning words is smaller, the lower Spurious in band of direct digital frequency synthesis.

Key words: DDS, apurious in band, AD9858