Abstract: The invention is directed to an optical node, e.g., a so-called add/drop site, that receives an optical carrier signal formed from a plurality of component optical signals of respective wavelengths and a plurality of different identification signals which identify respective ones of the wavelengths. As is typically the case, the node includes a demultiplexer that demultiplexes the optical carrier signal and outputs the demultiplexed component optical signals to respective optical paths. Disadvantageously, each of the demultiplexed optical component signals includes all of the identification signals as a result of such demultiplexing. However, we dispose an optical translator unit in at least one of the optical paths to remove all of the identification signals from the one component optical signals and also reset the power level of that signal.

Abstract: There is disclosed a super-high speed light transmission method making use of quasi-solitons in a fiber. Chirped stationary pulses are transmitted through the fiber. At a position where the effect of the chirp becomes weak and the sign of the chirp reverses, the sign of the chirp is reversed by a dispersion compensation fiber or fiber grating connected to the fiber in order to recover the initial chirp. The dispersion profile of each of the fibers is properly controlled in order to produce stationary quasi-solitons having a stable pulse shape. The method can prevent widening of pulses, which would otherwise occur due to dispersion.

Abstract: A wavelength aligning apparatus using an arrayed waveguide grating (AWG), and particularly, to a wavelength aligning apparatus using an arrayed waveguide grating which is capable of aligning optical sources using a transmission characteristic of an arrayed waveguide grating in a wavelength alignment method.

Abstract: An optical noise monitor measures noise power within narrow wavelength regions between channel signals of a dense wavelength division multiplexed (DWDM) signal. The noise monitor receives the DWDM signal and cascades the signal along a multipoint travel path where the signal is incident on a series of multi-pass filters. Each multi-pass filter selects a narrow, predefined wavelength region between channel signals of the DWDM signal. Noise power within the predefined wavelength region is detected and SNR is monitored by comparing the detected noise power to the power in the channel signal. According to a first preferred embodiment of the present invention, the noise monitor includes multi-pass filters that each have reflective surfaces to guide optical energy within a predefined wavelength region through multiple passes of an optical filter.