发明名称 |
Normalfrequenzgenerator |
摘要 |
A frequency standard generator includes a voltage controlled crystal oscillator for generating high stability output signal to be used as a standard frequency signal, a satellite wave receiver which receives a radio wave from a satellite which includes a highly accurate satellite time signal and reproduces the satellite time signal to be used as a reference for the voltage controlled crystal oscillator, a frequency divider which divides the output signal of the voltage controlled crystal oscillator by a dividing ratio arranged to generate a crystal time signal which is identical in frequency to the satellite time signal, a time interval measuring circuit which measures a time interval which is a phase difference between the satellite time signal and the crystal time signal and generates a digital signal indicating the phase difference, a frequency control processor which arithmetically determines control data based on the digital signal from the time interval measuring circuit such that the phase difference maintains a constant value through an operation of a phase lock loop, and a D/A converter which converts the control data from the frequency control processor to an analog voltage which is used to control the output frequency of the voltage controlled crystal oscillator. |
申请公布号 |
DE19543882(A1) |
申请公布日期 |
1996.05.30 |
申请号 |
DE1995143882 |
申请日期 |
1995.11.24 |
申请人 |
ADVANTEST CORP., TOKIO/TOKYO, JP |
发明人 |
UJIIE, HITOSHI, SENDAI, MIYAGI, JP |
分类号 |
G04G3/00;G01S1/00;G01S19/14;G04R20/00;G04R20/02;G04R40/00;H03L1/02;H03L7/06;H03L7/093;H04L7/033 |
主分类号 |
G04G3/00 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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