Abstract:
Provided are an optical transponder that processes a G.709 frame that includes an overhead for operation, administration, and maintenance of an optical channel and an overhead for forward error correction, and a method of detecting and treating errors in optical-channel sublayers of the same. The method includes detecting an error signal or a maintenance signal from a G.709 frame that includes an overhead for operation, administration, and maintenance of an optical channel and an overhead for forward error correction; treating errors in a predetermined layer of a plurality of layers that requires error treatment when the error signal or the maintenance signal is detected or canceled; and investigating a reason for the errors in the predetermined layer.
Abstract:
The present invention relates to a method for revising a wavelength of the EML by controlling a working temperature based on arithmetic functional relations between the DC-Offset voltage and the wavelength and between the working temperature and the wavelength, and a computer-readable recording medium thereof. The method includes the steps of: re-setting initial values of a working temperature, a amplifying voltage and the DC-Offset voltage; determining a wavelength with respect to the re-set DC-Offset voltage based on a functional relation between the DC-Offset voltage and the wavelength of the EML; and determining the revising working temperature for the determined wavelength based on the functional relation between the working temperature and the wavelength of the EML, and re-setting the working temperature with the revising working temperature.
Abstract:
A memory card includes a substrate and a resin-molded layer. The substrate includes contact pads that are on a second face thereof for communication with a card reader. Semiconductor chips are on a first face of the substrate and electrically connected to the contact pads through bonding wires and circuit wiring. The resin-molded layer is on the first face and covers the chips. The fabrication process for the memory cards begins with fabrication of a multi-substrate that includes several unit substrates. At least one semiconductor chip is provided on each unit substrate and electrically connected. A continuous resin-molded layer is then formed to extend over the unit substrates. Separating the unit substrates of the multi-substrate divides the continuous resin-molded layer into individual resin-molded units and provides the memory cards.
Abstract:
A purge system built with a purge box, pipes, valves, and a manifold panel. Apart from ventilation systems in ordinary gas cabinets, it is characterized by minimizing hazards through safe exhaust of toxic and reactive gases and through prevention of explosion and fire with complete cutoff of air (oxygen, in particular) in case of contamination and leakage arising in such pipes, valves and manifold panel involved in purging inert gases (Ar and N2). The purge box can preferably block external air from a joint area connecting gas pipes and a gas container, such as a cylinder, which is prone to leakage and contamination due to frequent attachments and detachments. In addition, a supply valve of the hazardous reactive chemical is closed, to avoid further releases. Physical and chemical damages resulting from attaching and detaching a cylinder mounted on a gas supply facility including existing or separate gas cabinets can be prevented.
Abstract:
Provided are an apparatus and method for maintaining an constant extinction ratio of a laser diode (LD). The apparatus includes: an automatic power control circuit maintaining the constant optical power of the LD; a correlation deriver deriving correlations between a bias current of the LD and a modulation current to maintain the constant extinction ratio of the LD; and a modulation current control circuit controlling the modulation current to maintain constant the extinction ratio of the LD based on the correlations. The apparatus and method do not use a temperature sensor but derive a relationship between variances of a bias current of the LD and a modulation current according to temperature change, control the modulation current based on the relationship, and maintain the constant extinction ratio of the LD.
Abstract:
An active alignment method for a multi-channel optical transmitter and receiver is disclosed. The active alignment method for a multi-channel optical transmitter includes actively aligning an optical signal generator with an optical multiplexer based on optical outputs of a plurality of wavelengths from the optical signal generator and an optical output of the optical multiplexer, and actively aligning the optical multiplexer with a fiber optic coupler based on an optical output of the optical multiplexer and an optical output of the fiber optic coupler.
Abstract:
An optical transceiver for optimizing transfer characteristic of an optical interferometer and a method of optimizing transfer characteristic of an optical interferometer of an optical transceiver are provided. It is possible to improve the transmission performance of the optical transceiver by optimizing the transfer characteristic of the optical interferometer included in an optical receiver of the optical transceiver which transmits and receives an optical signal in a phase modulation scheme.
Abstract:
Provided is an optical transponder that receives a tributary signal such as a SDH/SONET signal, a GbE (Gigibit Ethernet) signal, and a SAN (Storage Area Network) signal in a WDM (Wavelength Division Multiplexing) transmission system and a SDH (Synchronous Digital Hierarchy)/SONET (Synchronous Optical Network) system, and more particularly, to an optical transponder having a switching function. The optical transponder having a switching function includes: a switch changing a data path of an input tributary signal from a plurality of channels (ports); an STM-64/OC-192 mapper/demapper mapping the tributary signal switched to a different data path by the switch to an STM-64/OC-192 signal or demapping the STM-64/OC-192 signal to the tributary signal; and a transmission delay time compensator compensating for a differential delay caused by a transmission route difference on an optical fiber link when the STM-64/OC-192 signal is demapped to the tributary signal.
Abstract:
An active alignment method for a multi-channel optical transmitter and receiver is disclosed. The active alignment method for a multi-channel optical transmitter includes actively aligning an optical signal generator with an optical multiplexer based on optical outputs of a plurality of wavelengths from the optical signal generator and an optical output of the optical multiplexer, and actively aligning the optical multiplexer with a fiber optic coupler based on an optical output of the optical multiplexer and an optical output of the fiber optic coupler.
Abstract:
Disclosed is an optical transceiver module for controlling power in each lane. The optical transceiver module includes: a plurality of transmitting units formed in each lane in order to transmit signals to receive electric signals in each lane, convert the received electric signals into optical signals, and transmit the converted optical signals, respectively; a first switching means turning on/off power supplied to each of the plurality of transmitting units in each lane; a plurality of receiving units formed in each lane to receive optical signals in each lane, convert the received optical signals into electric signals, and output the converted electric signals, respectively; a second switching means turning on/off power supplied to each of the plurality of receiving units in each lane; and a control means controlling switching operations of the first switching means and the second switching means.