发明名称 |
FM modulator |
摘要 |
A branch portion 101 branches an inputted electrical signal into an in-phase signal and an opposite phase signal which have an opposite relation as to a phase. A first FM laser 104 converts the in-phase signal into an optical frequency-modulated signal (a first optical signal) having a center wavelength Delta1 and then outputs the resultant signal. A second FM laser 105 converts the opposite phase signal into an optical frequency-modulated signal (a second signal) having a center wavelength Delta2 and then outputs the resultant signal. The two optical signals are combined and then inputted into an optical-electrical converting portion 106. The optical-electrical converting portion 106 subjects the inputted optical signals to optical heterodyne detection by its square-law detection characteristic, and outputs a beat signal between the two optical signals which is a wide-band FM signal at a frequency corresponding to a wavelength difference Deltalambda(=|lambda1-lambda2|) between the first optical signal and the second optical signal. It is thus possible to increase frequency deviation of the outputted FM signal and thus greatly improve a CNR.
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申请公布号 |
US2004126121(A1) |
申请公布日期 |
2004.07.01 |
申请号 |
US20030734186 |
申请日期 |
2003.12.15 |
申请人 |
FUSE MASARU;UTSUMI KUNIAKI;FURUSAWA SATOSHI |
发明人 |
FUSE MASARU;UTSUMI KUNIAKI;FURUSAWA SATOSHI |
分类号 |
H04B10/04;H03C3/00;H04B10/06;H04B10/142;H04B10/152;(IPC1-7):H04B10/04 |
主分类号 |
H04B10/04 |
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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