Electronics and Telecommunications Research Institute

Other

Hae Geun Kim

Jong Hyun Lee

Jin Tae Kim

Jee Yon Choi

Kwangjoon Kim

Kwang Joon Kim

Bong Kyu Kim

Myung Hyun Lee

Seong-Soon Joo

Seung Han Lee

Seon Gyu Han

Byoung-whi Kim

Min Cheol Oh

Hyung Jong Lee

Sung Mo Yang

Woon Seob So

Hyuek Jae Lee

Hong Hyun Ha

Byoung-Sung Kim

Sung Wan Kim

Joo Heon Ahn

Choi Jee Yon

Yang Choong Reol

A method capable of optical packet switching even in a case where physical optical data in an optical packet switch has not the shape of a packet but the shape of continuous data, and a system therefore are provided. The optical switching method includes the steps of (a) detecting input terminals into which an optical packet is input, of an optical switch and switching the optical packet to destination output terminals of the optical packet, and (b) when there are the input terminals into which the optical packet is not inputted in step (a), detecting other input terminals into which the optical packet, which direct an output terminal among the plurality of output terminals connected to the input terminals, is inputted, and searching a blank output terminal and switching dummy data from the input terminal to the blank output terminal. Data having the shape of all input optical packets and data having not the shape of a packet but another shape can be switched into output terminals without omission, and thus data output when input data have the shape of continuous data maintain the shape of the continuous data.

Optical switching method and system therefor

A multi-dimensional optical cross-connect switching system. The system is capable of multi-dimensionally using wavelength resources, such as in the forms of optical fibers, optical wavelength bands and optical wavelengths. The system can three-dimensionally use the wavelength resources by being matched with an optical transport network through the optical fiber layer, optical wavelength band layer and optical wavelength layer. In addition, the multi-dimentional optical cross-connect switching system is constructed in such a way that two cross-connect switches are symmetrically arranged and an insertion/extraction switch is added to switch addition/dropping links between the two switches.

Multi-dimensional optical cross-connect switching system

Disclosed is a multiwavelength locking method and apparatus using an acousto-optic tunable filter in an optical communication system including optical transport networks, in which output wavelengths of light sources are monitored under the condition in which pilot signals are applied to the acousto-optic tunable filter, so as to lock the wavelengths of the light sources, thereby eliminating an wavelength instability of the light sources for an improvement in transmission characteristics. The acousto-optic tunable filter receives light beams of N different frequencies respectively outputted from N light sources, along with N pilot signals having different frequencies, and converts respective frequencies of beam components of the output beam corresponding to the N pilot signals, thereby outputting N frequency-converted output beams to be applied to a photo-detector. N electrical signals respectively corresponding to the frequencies of the pilot signals are outputted from the photo-detector, separated from one another while corresponding to the light sources, respectively, and then used to compensate for respective output wavelengths of the light sources, thereby enabling the corresponding light sources to output locked wavelengths, respectively.

Multiwavelength locking method and apparatus using acousto-optic tunable filter

An apparatus for controlling cycles of optical pulse streams based on a time correlation is disclosed. The feedback optical pulses and the input optical pulses are subjected to a time interleaving so as to make them not overlapped together, and then they are subjected to a time correlation, thereby considerably reducing the polarized beam dependence of the input optical pulse streams. The apparatus includes a clock generating means for generating clocks, and an optical pulse generating means for receiving the clocks from the clock generating means to generate optical pulses in synchronization with the pulses of the clock generating means. An input optical pulse distributing means distributes the feedback optical pulses of an output optical pulse distributing means, and distributes the optical pulses of the optical pulse generating means. A time correlation means correlates the time of optical pulses of the input optical pulse distributing means, and an optical pulse transferring/processing means amplifies and filters the optical pulses of the time correlation means to attenuate them. An output optical distributing means distributes the optical pulses of the optical pulse transferring/ processing means.

Apparatus for controlling cycles of optical pulse stream based on time correlation

A method of fabricating a thermooptic tunable wavelength filter of optical communication systems using WDM is provided, which includes the steps of forming a polymer optical waveguide on a semiconductor substrate using a polymer material, forming a polymer Bragg grating on the optical waveguide using O,RIE and polymer spin coating, and forming a thermooptic tuning electrode over the polymer optical waveguide in which the Bragg grating is integrated. This provides the thermooptical tunable wavelength filter which has very narrow wavelength band width of transmission signal, low crosstalk with optical signals adjacent thereto, stable wavelength tuning characteristic using thermooptic effect and wide tuning ranges. Furthermore, the optical devices using the polymer optical waveguide can be fabricated with low cost. Thus, they have advantages in terms of economy and marketability.

Method of fabricating thermooptic tunable wavelength filter

The present invention relates to a subscriber control module having a test apparatus suitable for testing internal routes in an Asynchronous Transfer Mode ATM exchange system for improved reliability and effective maintenance thereof. A subscriber control module having testing functions makes it possible that internal whole routes in the exchange system under the control by maintenance control module inside the system can be tested through the use of subscriber switching network and connection switching network. Further, a test apparatus of the present invention placed inside the exchange system can test ATM subscribers with individually different rates, configured in such a way to be identical with boards used in the exchange system so that the test apparatus can be installed inside the exchange system.

Subscriber control module having a test apparatus for asynchronous transfer mode

Growing community of inventors

Daejon, South Korea

Hae Geun Kim