摘要
针对深空测控系统高精度测量对于信道附加相噪的要求,采用直接数字频率合成(DDS)正交调制方法设计频率综合器。通过巧妙的试验和外推方法,择优选取电压型鉴相器,在锁相环相噪模型的基础上,全面分析各部分相噪的贡献,综合设计环路带宽,有效控制附加相噪,实现低相噪频综器最理想的目标,即环路带内的相噪完全由参考决定,带外的相噪由压控振荡器(VCO)决定,并采用两源互比的方法完成1 Hz极低相位噪声的测试,测试结果为-73 d Bc/Hz,与设计结果完全一致。该方法对于测控站极低相噪的设计具有一定参考价值。
For the additional phase noise requirements on channels in deep space TT&C system with high ac-curacy measurement,a frequency synthesizer is designed using direct digital synthesizing(DDS) quadrature modulation. A voltage-type phase discriminator is selected by smart test and extrapolation method. Based on phase noise model of phase locked loop,contributions from all parts of phase noise are analyzed. So the idea-lest performance of frequency synthesizer with low phase noise,i. e. loop in-band phase noise is depended on reference frequency,and out-band phase noise is determined by voltage-controlled oscillator(VCO),is implemented by loop bandwidth integrated design and efficient additional phase noise control. The 1 Hz low phase noise is tested through comparing two sources and it is-73 dBc/Hz,which is consistent with design re-sult. This method is valuable to low phase noise design in deep space TT&C ground station.
出处
《电讯技术》
北大核心
2015年第11期1249-1254,共6页
Telecommunication Engineering
关键词
深空测控系统
高精度测量
1Hz相噪
直接数字频率合成器
正交调制
电压型鉴相器
deep space TT&C system
high accuracy measurement
1 Hz phase noise
direct digital synthesizer
quadrature modulation
voltage-type phase discriminator
