摘要
详细地介绍了VLBI系统的地面单元中电缆延迟变化的测量方法,这种基于相位的测量方法,为相关领域的高精度延迟测量提供了借鉴。概要介绍了地面单元中电缆测量、反射调制以及相位比较器的工作原理,对各个环节作了数学上的推导分析。给出了一个电缆相对延迟值随温度变化的测试样本。
In this paper, the measurement of the cable delay that is within VLBI system＇s Ground Unit is described in detail. This measurement method gives out a useful reference in related fields of measureme in the the re nt. The theory of cable measurement, reflect modulation and phase comparator are introduced circuit theory section. The three parts are deduced and analyzed in mathematics. A sample of lative cable delay＇s variation versus temperature is given out at last
出处
《中国科学院上海天文台年刊》
2007年第1期119-127,共9页
Annals Shanghai Astronomical Observatory Chinese Academy of Sciences
关键词
地面单元
相位
测量
延迟变化
移相
调制
锁相环
ground unit
phase
measurement
delay variation
phase shift
modulation
phase lock loop
