发明名称 |
Optical PLL circuit and method of controlling the same |
摘要 |
An optical PLL circuit with high precision that has its simplified configuration. An optical-intensity modulator creates difference frequency information (Nx DELTA f) by modulating a received optical signal formed of signal optical pulses of a repetitive frequency (Nxf0) with a reference signal of a frequency (f0+ DELTA f) and implementing an AND operation of them. The signal is converted into an electric signal by a photo diode. A band-pass filter extracts only the low frequency component (Nx DELTA f). A frequency divider produces a frequency component DELTA f by dividing the extracted component by N. A multiplier receives the reference signal and the output signal f of a voltage-controlled oscillator and then creates the difference frequency component ((f0+ DELTA f)-f). A phase comparator compares the low frequency component DELTA f with the difference frequency component ((f0+ DELTA f)-f) and controls the voltage-controlled oscillator to set the phase difference between them to zero.
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申请公布号 |
US5894247(A) |
申请公布日期 |
1999.04.13 |
申请号 |
US19970985066 |
申请日期 |
1997.12.04 |
申请人 |
NEC CORPORATION |
发明人 |
YOSHIDA, MASANORI;YONEYAMA, KENICHI;TAURA, TOHRU |
分类号 |
H03L7/08;H04B10/00;H04B10/148;H04L7/033;(IPC1-7):H03L7/06 |
主分类号 |
H03L7/08 |
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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