Passive wavelength division multiplexing device for automatic wavelength locking and system thereof

A passive wavelength division multiplexing device for automatic wavelength locking, comprising:

• an optical multiplexer configured to allow a light having a corresponding wavelength to be outputted to one or more optical network units (ONUs) when a predetermined wavelength of a light beam inputted thereto is synchronized to a passband thereof;
• a splitter configured to split a part of the light outputted from the optical multiplexer into a plurality of light beams;
• an optical filter configured to allow the light beams splitted by the splitter to pass therethrough;
• an integrated optical receiver monitor configured to detect the intensity of the light beams that has passed through the optical filter and convert the detected light beams into electrical signals;
• a wavelength-tunable optical transmitter configured to allow a light beam having a specific wavelength to be inputted to the optical multiplexer while scanning the plurality of light beams having different wavelengths according to a temperature, and adjust a wavelength of an optical signal to be outputted to the optical network units (ONUs) through the optical multiplexer, into a wavelength of an optical signal having the maximum optical intensity to lock the wavelength using optical intensity information corresponding to the electrical signals converted by the integrated optical receiver monitor;
• an FSK Tx section configured to transmit its locked wavelength information using a frequency shift keying (FSK) signal or a subcarrier which is carried on the amplitude of payload data within a given percentage;
• a first photo detection section configured to detect the intensity of a light having a specific wavelength transferred thereto from the optical network unit (ONU) through monitoring;
• and
• a first polymer optical sub-assembly section configured to transmit the light having the specific wavelength detected by the first photo detection section using a polymer optical sub-assembly.