| 摘要 |
PROBLEM TO BE SOLVED: To restrain the fluctuation of a modulation state in an optical transmitter operated on an actual transmission line which is caused by temperature or other environmental conditions or degradation of components due to the lapse of time, thereby restraining degradation in signal quality.SOLUTION: An optical transmission device comprises: an optical signal source which generates an optical signal based on any modulation method; a drive clock source which outputs a drive clock at the same frequency as the repetition frequency of the optical signal; a phase modulator which adds phase modulation to the optical signal from the optical signal source by using the drive clock; an optical separator which branches output light from the phase modulator into a transmission path and a monitor path; optical branch means which branches monitor light from the optical separator into one or more wavelength bands by filtering; optical detection means which receives transmitted light in wavelength bands filtered by the optical branch means; a phase adjustment unit which adjusts the phase of the drive clock; an amplitude adjustment unit which adjusts the amplitude of the drive clock; and control means which controls the phase adjustment unit and the amplitude adjustment unit so that an optimum prechirp is added. |
