摘要:
Disclosed is a duobinary optical transmitter, which includes a laser source for outputting light with a predetermined wavelength; a Mach-Zehnder interferometer-type optical intensity modulator for modulating the intensity of the light according to a three-level data signal inputted through a modulation terminal; a low-pass filter for converting an inputted two-level binary data signal into a three-level data signal through an interference among codes; and, a modulator driver/amplifier for amplifying the three-level data signal and then outputting it to the modulation terminal, wherein the overall bandwidth of the low-pass filter, the modulator driver/amplifier, and the optical intensity modulator corresponds to approximately ¼ of the clock frequency of the two-level binary data signal.
摘要:
A precoder for an optical duo-binary transmission apparatus disposing the precoder before a time division multiplexer includes a judgment unit for judging whether an odd number or even number of ‘1’s exist in data input signals of N channels inputted at an nth time of channel input. Further included in the precoder is a toggle unit for toggling an output signal of the judgment unit when the judgment is odd, and for determining an output value for one of the channels. The precoder also has an output unit for determining output values of other channels according to a respective data input signal and a predetermined channel from among the N channels.
摘要:
A network system for interworking a Wireless Local Area Network (W-LAN) and a 3rd-Generation (3G) mobile communication network through a Radio-over-Fiber(RoF) link and an authentication method in interworking in the network system are provided. The network system includes a 3G mobile communication network and a W-LAN system. The 3G mobile communication network includes a voice signal processing network connected to a Public Switched Telephone Network (PSTN) for voice call processing with respect to a predetermined mobile terminal, a packet data network for data communication with the predetermined mobile terminal, and a terminal device for communication with the predetermined mobile terminal. The W-LAN system is connected to the packet data network of the 3G mobile communication network to provide a W-LAN service to the predetermined mobile communication terminal. The W-LAN system is implemented in a plurality of Base Transceiver Stations (BTSs) included in the 3G mobile communication network through the RoF link.
摘要:
A wavelength division multiplexed optical access network including a central office for multiplexing first optical signals used for transmitting a high-speed wire data service to a subscriber side and second optical signals used for transmitting a wireless data service to a remote subscriber terminal, a remote node connected to the central office through an optical fiber and for de-multiplexing a multiplexed optical signal received from the central office, a plurality of subscribers connected to the remote node, each subscriber receiving a first optical signal having a corresponding wavelength from among the de-multiplexed first optical signals, and a plurality of radio access units connected to the remote node, each radio access unit converting a second optical signal having a corresponding wavelength from among the de-multiplexed second optical signals into a wireless electric signal and wirelessly transmitting the wireless electric signal.
摘要:
An optical access network of wavelength division method and passive optical network using the same are disclosed. The wavelength division multiplexed optical access network includes a central office for multiplexing first optical signals for wire communication and second optical signals for wireless communication and a remote node connected to the central office through an optical fiber and for demultiplexing a multiplexed optical signal received from the central office. A plurality of subscribers may be connected to the remote node. Each subscriber receives a first optical signal having a corresponding wavelength from among the demultiplexed first optical signals. The network also includes a plurality of radio relay stations connected to the remote node, each radio relay station converting a second optical signal having a corresponding wavelength from among the demultiplexed second optical signals into a radio electric signal and wirelessly transmitting the radio electric signal.
摘要:
A wideband optical module includes a downward wideband light source for generating downward light, an upward wideband light source for generating upward light, a first circulator including a first to a third port for outputting multiplexed downward optical signals to the second port and for outputting multiplexed upward optical signals to the first port, a second circulator including a first to a third port for outputting multiplexed upward optical signals to the second port and for outputting multiplexed downward optical signals to the first port, a first optical coupler connected to the third port of the first circulator and the second port of the second circulator for outputting the downward light to the third port of the first circulator, and a second optical coupler connected to the second port of the first circulator and the third port of the second circulator for outputting the upward light to the third port of the second circulator.
摘要:
Disclosed is a wavelength-division-multiplexed passive optical network using a wavelength-locked optical transmitter. The wavelength-division-multiplexed passive optical network (WDM PON) includes a central office, which includes a plurality of downstream optical transmitters for outputting downstream optical signals having wavelengths according to downstream injection lights, a wavelength division multiplexer including a plurality of de-multiplexing ports linked to the plurality of the downstream optical transmitters by one-to-one, and a multiplexing port linked with the feeder fiber and performing wavelength division multiplexing and wavelength division de-multiplexing, and at least one optical switch interposed between the downstream optical transmitters and the de-multiplexing ports, inputting a downstream band light output from a selected downstream optical transmitter to the multiplexing port, and inputting a downstream optical signal output from a remaining downstream optical transmitter, which is not selected, to the de-multiplexing port.
摘要:
A method and apparatus for ensuring QoS in a synchronous Ethernet bridge are disclosed, in which a classifier classifies an ingress packet according to a PHB mapped to a DSCP value of the packet and provides the classified packet to one of a predetermined synchronous packet queue and a predetermined asynchronous packet queue, a buffer queue with a plurality of queues mapped to priority levels buffers the classified packet, a marker marks the buffered packet as a synchronous packet or, if the buffered packet is an asynchronous packet, marks the packet in a predetermined format corresponding to a priority level of the packet, and a synchronous Ethernet scheduler schedules the marked packet.
摘要:
A bi-directional WDM-PON and a method for allocating a wavelength band are disclosed. In the bi-directional WDM-PON, bi-directional transceiver modules are used to transmit optical signals of different wavelengths in the upstream and downstream directions. An L-band and an S-band are used to allocate wavelength bands to the upstream and downstream optical signals so that a wavelength band interval at which the respective wavelength bands of the upstream and downstream optical signals are spaced is set between 50 nm to 150 nm.
摘要:
A method and apparatus for ensuring QoS in a synchronous Ethernet bridge are disclosed, in which a classifier classifies an ingress packet according to a PHB mapped to a DSCP value of the packet and provides the classified packet to one of a predetermined synchronous packet queue and a predetermined asynchronous packet queue, a buffer queue with a plurality of queues mapped to priority levels buffers the classified packet, a marker marks the buffered packet as a synchronous packet or, if the buffered packet is an asynchronous packet, marks the packet in a predetermined format corresponding to a priority level of the packet, and a synchronous Ethernet scheduler schedules the marked packet.