摘要:
A photoelectric cross-connect system for an optical-communication system minimizes service recovery time when an error is generated. A plurality of nodes are connected by an optical-transmission line wherein each nodes automatically recognizes a data rate of an input signal and communicates over a redundant channel with an adjacent node when there is a certain type of error. An optical-receiving unit receives an optical signal performs O/E conversion. A main optical-transmitting unit recovers clock and data signals according to the converted signal and sets a data rate according to the converted signal for subsequent transmission; a redundant optical-transmitting unit recovers a clock and data according to the converted signal and sets a data rate according to the converted signal for subsequent transmission A switch provides selectively connection state between the optical-receiving unit and the main optical-transmitting unit and between the optical-receiving unit and the redundant optical-transmitting unit.
摘要:
Disclosed is a wavelength division multiplexing-passive optical network (WDM-PON) that integrates broadcast and communication data, and transmit using WDM. An optical line terminal (OLT), connected to a broadcasting network and an Internet protocol (IP)-network, receives a digital broadcast signal from the broadcasting network and a first communication signal from the IP network, and transmits them as a single (broadcast/communication) integrated optical signal after photoelectric conversion, and further transfers a second communication signal from a service user to the IP network. An OLT/ONU on the user side transfers integrated optical signal from OLT to the user, and transfers channel-information data of a digital broadcast desired by the user and user data including the second communication signal from the user to the OLT. A first WDM demultiplexer WDM-demultiplexes the single signal and transfers it to the OLT/ONU. A first WDM multiplexer WDM-multiplexes the user data and transfers it to the OLT.
摘要:
Disclosed are an apparatus and a method for shortening a processing time at each node in an optical network. A transmission optical cross-connect (OXC) determines a transmission rate corresponding to the transmission speed of the signal to be transmitted. An optical receiver and an optical transmitter are stabilized by means of the transmission rate. In addition, a transmission OXC transmits the transmission rate to an OXC aligned between the transmission OXC and the receiving OXC, thereby stabilizing the OXC. Each of the OXCs detects the transmission speed of the optical signal to be received so that a time required for converting the transmission speed is reduced.
摘要:
A residential Ethernet switching device for sub frame-based switching in a residential Ethernet system is provided. The device includes a plurality of reception data path processors for parsing a residential Ethernet frame inputted to the residential Ethernet switching device, as respective residential Ethernet sub frames, and outputting the parsed residential Ethernet sub frames, a switch fabric for switching the residential Ethernet sub frames inputted through the plurality of reception data path processors, a plurality of transmission data path processors for providing an output path for multiplexing and outputting the residential Ethernet sub frames switched through the switch fabric, and a local cycle counter connected to the plurality of reception data path processors, the switch fabric, and the plurality of transmission data path processors, and providing cycle counter information on the respective residential Ethernet sub-frames.
摘要:
A method for transmitting asynchronous data includes including: comparing a size of asynchronous data with that of an empty transmission area; inserting the asynchronous data into the empty transmission area when the asynchronous data has a size smaller than or equal to that of the empty transmission area; determining if the empty transmission area has a size larger than a predetermined threshold value when the asynchronous data has a size larger than that of the empty transmission area; transmitting the asynchronous data with the empty transmission area left when the empty transmission area has a size smaller than the predetermined threshold value; and segmenting the asynchronous data according to the size of the empty transmission area when the empty transmission area has a size larger than the predetermined threshold value, inserting the segmented asynchronous data into the empty transmission area, and transmitting remaining segmented asynchronous data in a subsequent transmission cycle.
摘要:
An embedded system using binary-position information and capable of updating software more promptly is disclosed. The embedded system includes a server for receiving software-version information from a target system for a comparison of a binary image associated with the received software-version information with a binary image corresponding to a new software version and generating a changed binary image and position information in the data to be downloaded, and a target system for analyzing the data downloaded from the server and updating the binary image with reference to the position information.
摘要:
A subscriber distribution system for distributing broadcasting data to subscribers through a subscriber network. The subscriber distribution system has a PID filter section for checking contents of an inputted MPEG2 MPTS frame and splitting the MPEG2 MPTS frame into SPTS, a table regenerator for regenerating a PAT and a PMT that correspond with the SPTS by changing contents in the PAT and the PMT. An SPTS splitting and storing section stores the SPTS at high speed in a memory area of a buffer, which is assigned to subscribers according to PIDS. A subscriber distribution section selecting the SPTS requested by subscribers and storing the SPTS in the memory area of the buffer assigned to subscribers. A control section receives MPTS information from a higher network to provide MPTS information to the PID filter section and the table regenerator, and receives a request for a program from subscribers, and transfers the request to the subscriber distribution section.
摘要:
Disclosed is an optical add/drop multiplexer connected to an optical fiber for transmission of a multiplexed optical signal, and adapted to add a channel to the optical signal or to drop a channel from the optical signal. The optical add/drop multiplexer includes a wavelength division multiplexing/demultiplexing (WDM) unit connected to the optical fiber, having input and output ports providing a path for a multiplexed optical signal, and a plurality of demultiplexing ports respectively providing paths for demultiplexed channels. A plurality of add/drop multiplexer (ADM) units respectively connected to the demultiplexing ports of the WDM unit, each of the ADM units including first and second circulators each adapted to output a channel, input to a higher-order port thereof, to a lower-order port, and a reflector for passing or reflecting a channel inputted thereto. The first circulator receives a channel at a second port and outputs the channel to a third port connected to the reflector. The first circulator receives, at the third port, the channel from the reflector, and outputs the secondarily received channel to a fourth port, thereby dropping the channel. The second circulator receives a channel at a first port, outputs the received channel to a second port connected to the reflector, receives, at the second port thereof, the channel from the reflector, and outputs the secondarily received channel to a third port connected to a first port of the first circulator, thereby adding the channel.
摘要:
Disclosed is an opto-electrical cross connect device of high density including a shelf having a plurality of guide rails at its inner portions; a switch motherboard disposed on the rear surface of the shelf; an electric crosspoint switch positioned on the front surface of the switch motherboard; a plurality of switch connectors positioned on the front surface of the switch motherboard; an optical transceiver board mounted in the guide rail of the shelf; and, a transceiver connector disposed at the rear end of the optical transceiver board for connecting to the switch connector of the switch motherboard.
摘要:
Disclosed is an apparatus and method for constructing and broadcasting a multi-screen broadcasting program by using a transport stream in a digital broadcasting, and for decoding the constructed transport stream to restore image and voice signals. The method includes the steps of analyzing a program access table (PAT) of broadcasting data to determine whether there are at least two image packets, performing signal decoding when the input broadcasting data is a single screen program having one image packet, performing a multi-decoding when the input broadcasting data is a multi-screen program having at least two image packets.