摘要
介绍了Σ-Δ调制在锁相小数频率合成的中的作用。提出了传统的吞脉冲技术在鉴相频率提高后出现的问题,即高鉴相频率意味着分频比的降低,而在没有很低模式变模分频器时吞脉冲技术无法获得较低的分频比,于是提出了一种新的基于变模分频的解决方案:通过按照一定规律改变分频器模式实现了高鉴相频率的Σ-Δ调制小数分频,经过对小数分频输出频率测量的实验验证后得到了很好的结果。
This paper introduces the function of∑-△modulation in decimal frequency synthesis of phase-locked loop and Indicates the problem appeared using traditional technology of devouring pulse when heightening the phase comparison frequency, which is that the higher phase comparison frequency means the lower the frequency division ratio. It can＇t get lower frequency division ratio using technology of devouring pulse when very low modulus Changing-modulus frequency divider is not available. Therefore advancing a new project based on frequency division of changing modulus： realizing high phase comparison frequency decimal frequency division of ∑-△modulation through changing the modulus of the frequency divider according to some rules. A favorable result of frequency is gained after experiment of the measure of decimal frequency output.
出处
《国外电子测量技术》
2008年第1期31-34,共4页
Foreign Electronic Measurement Technology
关键词
∑-△调制
锁相环
小数频率合成
高鉴相频率
∑-△modulate
phase-locked loop
decimal frequency division
high phase comparison frequency
