OPTICAL TRANSMITTER AND METHOD FOR CONTROLLING THE SAME

摘要

Since it is difficult to emit a stable and reliable modulated lightwave signal by means of IQ modulators used for QAM format, a method for controlling an optical transmitter according to an exemplary aspect of the invention includes the steps of (a) keeping an optical amplitude of a continuous wave light output from the optical transmitter constant, (b) making operating point values in optical modulation converge to predetermined values during step (a), and (c) modulating the continuous wave light with multiple amplitudes and phase levels around the operating point values converged in step (b).