| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical system suitable for ensuring long-term stability, improving reliability and speeding up a response, when monitoring and controlling WDM signal light. <P>SOLUTION: An optical system comprises an optical processing means for performing at least one processing among relaying, branching and switching of signal light that is transmitted by a main optical path and subjected to wavelength division multiplexing; and a monitoring means for monitoring the spectrum of the wavelength multiplexed signal light. There are further included: a means for dispersing the wavelength multiplexed signal light for monitoring; a light-receiving device array including a plurality of photoelectric conversion elements at positions each for receiving the dispersed signal light; a means for calculating the spectrum of the signal light by performing the operation on the basis of the output signal of the light-receiving device array; a means for calculating a signal-to-noise ratio by respectively calculating a ratio between peak power of each signal light and a noise component near each signal light; a means for detecting true signal power in the wavelength multiplexed signal light for monitoring on the basis of the calculated signal-to-noise ratio; and a means for controlling an optical amplifier on the basis of the detected true signal power. <P>COPYRIGHT: (C)2009,JPO&INPIT |
