Abstract: Disclosed is a Fabry-Perot laser device connected with an optical transmission link. The device comprises an optical circulator for forming an optical waveguide loop and circulating light through the optical waveguide loop and for outputting light from the optical waveguide loop through an external port; an optical fiber amplifier located on the optical waveguide loop and for amplifying the light circulating in the optical waveguide loop; a laser light source connected with the exterior port and being self-seeded by the light inputted through the exterior port and for outputting wavelength-locked light to the exterior port; and, a first splitter located on the loop for splitting a portion of the circulating light and for outputting the split-off light to the optical transmission link.

Abstract: A peak detector for detecting a peak value of a burst signal in a burst mode optical receiver is disclosed, which comprises: an amplifying terminal configured to reduce an offset of a peak value in a received burst signal using feedback in the peak detector; a transistor that functions as a diode when a positive signal is received from the amplifying terminal; a peak hold capacitor for charging a peak value when the transistor received the positive signal; a signal amplitude detector to monitor the received burst signal amplitude; and a current source to drive a current responsive to the output signal amplitude detector.

Abstract: The object of this invention is to provide a non-calcined clay composite used as building materials capable of promoting humans' health and being desirably used irrespective of location, which is improved in terms of strength without calcining clay. Because the non-calcined clay composite is produced without calcining clay, the process of producing it is simplified and its productivity is improved. The non-calcined clay composite includes 50 to 90 wt % clay, 2 to 30 wt % lime, 4 to 48 wt % blast furnace slag, 0.04 to 0.9 wt % alkaline chemical, and water as a balance, and has high compression strength due to an ionic coagulation reaction, a pozzolan reaction, and a latent hydraulic reaction.

Abstract: The present invention relates to a device and method for managing a communication equipment, such as a router or a switch, using a command-line interface (CLI). A managing unit managing the communication equipment stores management information, which is a newly added software module or command, in a string format in a management file storage, and the management information is parsed in a parser and a newly registered management information is added to a database, thereby registering new management information without the need of compiling a CLI agent.

Abstract: Disclosed is a method, apparatus and computer product for controlling proportional allocation transmission through an OLT scheduling algorithm in an EPON based FTTH system. The method includes computing a total transmission capacity for Optical Network Terminations (ONTs) connected to the OLT, computing a number of transmissions according to the ONTs, storing the computed number of transmissions according to the ONTs in a storage unit, determining a transmission order for each ONT based on the number of transmissions according to the ONTs, and transmitting data according to the determined transmission order.

Abstract: A local switching method using a logical link ID (LLID) in an Ethernet passive optical network (EPON) system is disclosed. The local switching method includes a first step of an optical network unit (ONU) receiving and separating data inputted through a user port into a wide area network (WAN) traffic and a local area network (LAN) traffic, allocating the LLID according to a service for each traffic to the separated WAN traffic and LAN traffic, and transmitting the WAN traffic and LAN traffic with the LLIDs allocated thereto; and a second step of an optical line termination (OLT) receiving the WAN traffic and LAN traffic with the LLIDs allocated thereto transferred from the ONU, extracting a destination of the corresponding traffic through the LLIDs, and transmitting the respective traffic accordingly.

Abstract: Disclosed is an IP-based broadcast service system capable of reducing the channel zapping or changing time and the waste of bandwidths during frequent channel changes such as channel surfing. A broadcast server for providing broadcast services generates both high-quality broadcast data and low-quality broadcast data of each TV channel. The broadcast server provides the low-quality broadcast data during a simple channel surfing. When a viewer selects a channel to view, the broadcast server then provides the high-quality broadcast data of the selected channel.

Abstract: A solution for allowing conditional access to IP-based broadcast services in a passive optical network is disclosed. When a subscriber requests broadcast services by selecting a broadcast channel, an IP set-top converts the request into an IGMP join message and forwards the message to an ONU/ONT, a unit on the subscriber's side. The ONU/ONT delivers the message to an OLT interworking with a router while storing mapping information of the port that received the message and a MAC address of the selected channel. Thereafter, the OLT extracts information on MAC address of the IP set-top box and the requested broadcast data. The OLT compares the extracted information to the subscriber's subscription information and determines whether to provide the requested broadcast services. If the broadcast services may be provided, the broadcast data provided from the broadcast server is transmitted to the IP set-top box via ONU/ONT based on the stored mapping information.

Abstract: Example embodiments of a semiconductor chip packaging apparatus and method thereof are disclosed. The packaging apparatus may include a plating unit to perform a conductive plating process to form a conductive plating layer on external terminals of a semiconductor chip package, and a reflow unit adapted to melt the conductive plating layer. The plating unit and reflow unit may be disposed in a single line with the plating module. Thus, it is possible to effectively suppress the growth of whiskers on the plating layer of the external terminals, and to secure economical efficiency, reducing costs, and allowing mass production.

Abstract: Disclosed is a temperature controller and method for maintaining an optical-communication device at a constant temperature regardless of ambient temperature variation.

Abstract: A method for managing an IP address statically allocated to a slave slot through a master slot is disclosed If the power of a slave slot is on, confirming whether the slave slot has a static IP, and if not, confirming whether the slave slot has a DHCP (Dynamic Host Configuration Protocol) IP. Confirming whether the slave slot has a slot ID from a backplane if the slave slot has the static IP, and confirming whether the slave slot has the slot ID from the backplane if the slave slot has the DHCP IP. Confirming whether a master slot has a static IP, and performing an IPC communication if the slave slot has the slot ID. If the slave slot has neither the static IP nor the DHCP IP, a discovery operation is performed to obtain the IP information if the master slot does not have the static IP.

Abstract: The present invention relates to Wavelength Division Multiplexing (WDM) based optical communications, and more particularly to an Fabry-Perot (FP) laser apparatus mode-locked to a multi-frequency lasing light source and an optical transmission apparatus using the same.

Abstract: An automatic gain controller for controlling gain values of an optical fiber amplifier. The automatic gain controller includes a first opto-electric conversion unit for converting a portion of optical signals that are input into the optical fiber amplifier into electrical signals to output the converted electrical signals. A second opto-electric conversion unit converts a portion of output optical signals output from the optical fiber amplifier into electrical signals and then outputs the converted electrical signals. A transient suppressing unit generates pulse typed waveforms when a change in channel number is generated during monitoring outputs of the first opto-electric conversion unit, and a comparing unit compares the sum of output signals of the transient suppressing unit and output signals of the first opto-electric conversion unit with output signals of the second opto-electric conversion unit.

Abstract: A bit rate control apparatus having a delay unit for delaying an input signal received in an optical receiver in an optoelectrically-converted state; a DC level outputting unit for exclusively OR'ing the input signal with the delayed signal outputted from the delay unit; an A/D converting unit for A/D converting a DC level outputted from the DC level outputting unit; a clock/data reproducing unit for reproducing clocks and data based on a bit rate control signal; and a control unit for calculating a variation in the DC level at every interruption timing, which is previously set, based on the A/D converted signal, and for determining whether the DC level variation occurs under the influence of temperature or due to a variation in bit rate based on a difference between the calculated DC level variation from a predetermined variation limit.

Abstract: A temperature compensation device for an optical communication device or the like is constructed so that an error value, which is the difference between the current temperature and a reference temperature, is subjected to digital processing in a temperature comparison unit. A digital error voltage value is calculated and digital PID control is performed instead of analog PID which requires electric components such as a power op-amp, a resistor (R), and a capacitor (C). According to this construction it is possible to reduce the number of electric parts. It is also possible to accept various types of temperature sensors while using only one PCB regardless of the types of temperature sensors utilized.

Abstract: The present invention is directed to a bidirectional add/drop multiplexer connected with waveguides at opposite ends thereof, respectively, and adapted to add/drop a channel in forward and reverse directions.

Abstract: A fiber to the home (FTTH) system based on a passive optical network (PON) includes an optical line terminal (OLT) block, an optical network terminal (ONT) block, and an optical distribution network (ODN). The ONT block includes a video-optical line terminal (V-OLT) and an optical line terminal (OLT) in order to output optical signals of the video-optical line terminal (V-OLT) and the optical line terminal (OLT) by multiplexing the optical signals. The VOLT receives cable TV, master antenna TV, and satellite broadcasting optical signals inputted from a broadcasting service network so as to output received signals as a first optical signal having a predetermined wavelength band. The OLT includes a first downstream data optical transmitter and a first upstream data optical receiver and outputs a data communication signal inputted from a data service network as a second optical signal having different wavelength from the video-optical line terminal.

Abstract: The object of this invention is to provide a non-calcined clay composite used as building materials capable of promoting humans' health and being desirably used irrespective of location, which is improved in terms of strength without calcining clay. Because the non-calcined clay composite is produced without calcining clay, the process of producing it is simplified and its productivity is improved. The non-calcined clay composite includes 50 to 90 wt % clay, 2 to 30 wt % lime, 4 to 48 wt % blast furnace slag, 0.04 to 0.9 wt % alkaline chemical, and water as a balance, and has high compression strength due to an ionic coagulation reaction, a pozzolan reaction, and a latent hydraulic reaction.

Abstract: A system and method for managing link status in Gigabit Ethernet passive optical network (GE-PON) units (ONUs) is disclosed. The GE-PON comprises one or more ONUs allocated data transmission periods, respectively. Each of the ONUs sends a report signal and a data signal in a corresponding one of the allocated data transmission periods. The report signal contains a signal to request allocation of a bandwidth for data signal transmission in a next window period. The GE-PON further comprises an optical splitter having its one side connected with the ONUs and its other side connected with at least one optical communication channel. The optical splitter switches an input signal to a desired destination.

Abstract: An Ethernet passive optical network provides a subscriber with a high speed and large capacity data service and a real time digital broadcast/video service. The network includes an optical line terminal for frame-multiplexing broadcast/video signals, which are obtained by performing a switching operation and a time-slot multiplexing with respect to a plurality of digital broadcast/video data delivered from external broadcasting vendors according to broadcast/video selection information delivered from each user, and communication data delivered through an Internet protocol network.