| 摘要 |
<P>PROBLEM TO BE SOLVED: To avoid the phenomenon which disables signal communication by erroneously setting a light phase. <P>SOLUTION: A VDC 1a receives an optical signal and performs dispersion compensation on the optical signal using a dispersion compensation value given from a control section 30. A demodulation section 10 makes information about phase modulation of the dispersion compensated optical signal into information about strength modulation, detects a strength-modulated optical signal and converts the optical signal into an electric signal. A data playback section 20 extracts a clock from the electric signal and plays back data. In a case where the data playback section 20 is not normally operated within a fixed time although it is recognized that the light phase is set to delay interferometers 11-1, 11-2 when activating the apparatus, the control section 30 determines that erroneous setting of the light phase has been executed, and performs sequence control for sequentially setting different dispersion compensation values until setting the light phase to the delay interferometers 11-1, 11-2 and recognizing the normal operation of the data playback section 20. <P>COPYRIGHT: (C)2010,JPO&INPIT |
