| 摘要 |
An apparatus is provided for using modulation signals to optically modulate lightwaves of multiple frequencies, using a single optical modulator. A multiple-wavelength optical modulation apparatus in which with respect to a natural number n that is not higher than a number N of modulation signals that is not lower than a number of input lightwaves, fn is input light component of channel n, Fn is modulation frequency, An is a lower sideband order and Bn is an upper sideband order corresponding to sideband channels generated by modulation, the apparatus comprises: an input filter, an optical modulator and an output filter on a single optical path; A lightwave input through an input filter is reflected between the input filter and an output filter, being modulated during each round trip, and is output via the output or input filter when the light has reached a frequency determined by the output or input filter. The time required for each light component of channel n to make a round trip is an integer multiple of one period of each modulation signal having a frequency Fn (=1/F<SUB>n</SUB>). A light component travelling in one direction is reverse phase modulated when the round-trip time is an odd multiple of one period (=1/F<SUB>n</SUB>), and a light component travelling in both directions is in phase modulated when the time required for the light component to travel both ways is an even multiple of one period (=1/F<SUB>n</SUB>).
|
