| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an FSK demodulator usable for optical information communications, etc. which compensates for the delay in an optical FSK modulated signal due to the dispersion, etc. of an optical fiber, thus suitably demodulating the FSK signal. <P>SOLUTION: The frequency shift keying (FSK) demodulator 1 comprises a means (2) for branching an optical signal according to its wavelength, a means (3) for adjusting the delay times of two lights branched by a branching filter, a means (4) for detecting one branched optical signal by the branching filter, a means (5) for detecting the remaining branched optical signal by the branching filter, and a means (6) for computing the difference between an output signal of a first optical detector and an output signal of a second optical detector. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
