Abstract:
PURPOSE: A coherent optical receiving device for digital equalization of optical signal is provided to optimize an equalizer of the device regardless of color distribution value. CONSTITUTION: A coherent optical receiving device comprises: a chromatic dispersion compensation unit(126) for compensating color dispersion to digital signal corresponding to optical signal using a filter; a decoder for generating bit sequence to the compensated signal; a bit error calculator(132) for calculating bit error quantity to the bit sequence; and a control unit for setting determined filter coefficient.
Abstract:
PURPOSE: An optical coherent receiver and an optical signal processing method are provided to accurately estimate a frequency, thereby preventing influences of a distorted phase occurring an RZ pulse cover and compensating for the distorted phase. CONSTITUTION: A frequency offset compensating unit(370) estimates a frequency offset about at least one of even samples and odd samples which are inputted from a polarization demultiplexer. The frequency offset compensating unit compensates for the frequency offset of the even samples and odd samples using the estimated frequency offset. A cover distortion compensating unit(390) compensates for distorted phases of the samples whose frequency offsets are compensated for. The distorted phase is generated from a light transferring device.
Abstract:
본 발명은 파장분할 다중화(wavelength division multiplexing) 광 전송 기술이 구현된 광 네트워크에 관한 것으로, 타 노드로부터 광신호를 입력받는 다수의 입력단과 타 노드로 광신호를 전송하는 다수의 출력단을 포함하고, 상기 입력단들 중 하나로 입력된 광신호가 상기 출력단 들 중 하나의 출력단으로 출력되도록 경로를 스위칭하는 경로 스위칭부; 및 상기 입력단으로 입력된 광신호의 파장을 변환하여 상기 경로 스위칭부에서 스위칭 결과에 따라 상기 출력단으로 출력하는 파장 변환부; 를 포함하는 것을 특징으로 하는 광 회선 분배 장치에 의해 파장 충돌로 인해 네트워크 자원의 비효율적 사용을 막을 수 있고, 자동으로 회선 분배가 가능하여 빠른 경로 설정이 가능하며, 파장에 상관없이 광신호의 경로 스위칭 및 분기/결합이 가능하고 광신호를 방향에 관계없이 스위칭 가능하다는 효과가 있다. 회선 분배, 파장변환, 광통신망
Abstract:
PURPOSE: A channel allocation method of a transferring system for wavelength division multiplex method and an apparatus thereof are provided to supply in order to control interference between channels. CONSTITUTION: A plurality of light transmitters(800-1~800-N) processes an optical signal for transferring according to the fixed signal modulation method and a signal transferring speed. A channel assigning unit(810) obtains the signal modulation method and signal transferring speed information from a plurality of light transmitters. The channel assigning unit assigns the channel to the light transmitters with considering. The channel assigning unit assigns the channel to be adjacent a phase-modulated optical signals.
Abstract:
PURPOSE: An optical transmission device for outputting stable optical signal is provided to steadily control the phase difference between two MZ modulators of the QPSK(Quarternary Phase Shift Keying) light modulator and two arms at the same time. CONSTITUTION: An optical modulator(610) comprises parallel-connected Mach-Zehnder interferometer type of a first modulator(620) and a second modulator(630). The light modulator performs the QPSK(Quarternary Phase Shift Keying) modulation by inputting output optical signal of the light source(600). By controlling an bias respectively about the first modulator and the second modulator and the light modulator, a output stabilizer stabiles a finical output signal of the light modulator.
Abstract:
PURPOSE: An optical path distribution device in a wavelength division multiplexing system and a method for the same are provided to eliminate the requirement of signal wavelength presetting when an optical signal is branched/combined from each network node of the wavelength division multiplexing system to a local network. CONSTITUTION: A path switching unit(100) comprises input terminals(10-1~10-4) which receives optical signals from other node and output terminals(15-1~15-4) which transmits the optical signals to other node. The path switching unit switches a path so that an optical signal inputted to one among the input terminals is outputted to one output terminal. A wavelength converting unit(200) changes the wavelength of the optical signal inputted to the input terminal in order to output the result to the output terminal according to switching result. The path switching unit comprises a branch unit which amplifies, branches, and outputs the signal inputted to the connected input terminal and a signal selecting unit.
Abstract:
An apparatus and a method for optical label exchange and payload reproduction, and an optical switch apparatus using the apparatus are provided to pass a signal, which is not diverged or combined in a node, in an optical signal format without converting into an electric signal, and convert a label signal into an electric signal to recognize and update path information, thereby exchanging a label efficiently, and reproducing, switching, and transmitting a payload signal on an optical burst signal transmission network. An apparatus(220) for optical label exchange and payload reproduction comprises an envelope detecting unit(222), a payload processing unit(221), and a label processing unit(223). The envelope detecting unit converts the phase of two signals to output the payload of an optical burst or the envelope of a label. The two signals are signals that the optical burst signal is converted into an electric signal. The payload processing unit synchronizes the optical burst signal with the envelope detected in the envelope detecting unit, extracts a payload signal included into the optical burst signal, and reproduces the extracted payload signal optically or converts the wavelength of the extracted payload signal. The label processing unit synchronizes the optical burst signal with the envelope detected in the envelope detecting unit, extract a label signal included into the optical burst signal, and converts the extracted label signal according to a path through the optical burst signal is transmitted.
Abstract:
An optical network node device is provided to manage optical network efficiently by simultaneously processing transmission of small capacity and large quantity transmission of a wavelength channel. A plurality of 4-terminal ROADM(Reconfigurable Optical Add Drop Multiplexer)(700,710,720,730) passes or drops a WDM(Wavelength Division Multiplexing) channel, or adds the WDM to a WDM wavelength channel which passes an optically converted signal so as to pass them together. Optical transceivers perform photoelectric conversion to a signal dropped from a corresponding ROADM or optically convert an electric signal transmitted to a corresponding ROADM. A switch(780) redistributes transmission capacity, cross-connects the signals which are converted by the optical transceiver, switches the signals to one of optical transceivers corresponding to a direction in which the signal will pass and transmits the signals to a corresponding ROADM.
Abstract:
A photonic cross-connector system, a WDM(Wavelength Division Multiplexing) system using the same, and an optical communication network based on the same are provided to switch a single wavelength from an arbitrary input port to an output port, to implement an optical multicasting function, and to convert a deteriorated signal into a noise-cancelled, clean signal. A photonic cross-connector system comprises an optical coupler(100), a WSS(Wavelength Selective Switch), a WDM multicasting unit(300), an optical transceiver(400), and a circuit distributor control system(500). The optical coupler drops an inputted optical signal to many paths. The WSS extracts at least one wavelength signal from an inputted signal and outputs the extracted signal to at least one port. The WDM multicasting unit simultaneously reproduces and regenerates an inputted signal into a plurality of signals having different wavelengths. The optical transceiver executes a signal add-drop function, and the circuit distributor control system controls each of the units.