Patent ID: 7907850
Filing Date: 2011-03-15
Classification: H04B,H04L

Abstract:
1. An optical communication device for sequentially transmitting a plurality of optical pulses to another optical communication device, wherein the plurality of optical pulses are modulated in both phase and intensity, comprising: an optical modulator having an interferometer structure which includes a plurality of optical waveguides and electrodes each corresponding to the waveguides, wherein the optical modulator allows both phase and intensity of each optical pulse to be modulated at the same time according to driving signals each applied to the electrodes; and a driver for driving the optical modulator by generating the driving signals from modulation information for separately modulating the phase and the intensity of each optical pulse; and a loop-back section for receiving each optical pulse from said another optical communication device and returning each modulated optical pulse to said another optical communication device, wherein the optical modulator is provided at a predetermined position on an optical path in the loop-back section, each optical pulse passing through the optical modulator in opposite directions, wherein the optical modulator modulates the intensity of each optical pulse, the intensity being selected from a plurality of intensity levels including a very weak level.