摘要:
An optical switch section that switches the path of an optical packet transmitted thereto and outputs the optical packet, and a control section that generates multiple switch control signals in accordance with the destination of an optical packet transmitted thereto, transmits the multiple control signals to the optical switch section through multiple signal transmission lines and controls the ON/OFF states of multiple optical switches are included, and delay measuring means for measuring a difference in delay time among the multiple signal transmission lines is provided. In this case, the control section adjusts the transmission times of the multiple switch control signals such that the difference in delay time measured by the delay measuring means can be cancelled and that the multiple switch control signals transmitted through the multiple signal transmission lines can arrive at the multiple optical switches simultaneously and transmits the multiple switch control signals.
摘要:
An optical switching system having a transmission node. The transmission node includes a bit pattern processing unit for processing a bit pattern of transmitted data to stabilize optical power of a frame signal light to be monitored and a frame signal light producing unit for producing frame signal light to be transmitted on the basis of the bit pattern processed by the bit pattern processing unit.
摘要:
A drive circuit is provided for a semiconductor optical amplifier type gate switch includes a first transmission path and a second transmission path. The first transmission path includes a common first sub-path between a signal source and a first node; and an individual second sub-path for each of a plurality of operational amplifiers between the first node and a corresponding one of the operational amplifiers. The second transmission path includes an individual third sub-path between each of the operational amplifiers and a second node; and a common fourth sub-path between the second node and the semiconductor optical amplifier type gate switches. Transmission delay times of all the individual second sub-paths are equal, and transmission delay times of all the individual third sub-paths are equal.
摘要:
The present invention relates to an optical switch apparatus made to successively carry out the route switching with respect to frame signal light inputted through various paths while eliminating the dispersion of an output power value. In the optical switch apparatus, input side deflecting units are disposed in corresponding relation to a plurality of input ports and output side deflecting units are disposed in corresponding relation to a plurality of output ports. Each input side deflecting unit and each output side deflecting unit are constructed in a manner such that a plurality of optical deflecting elements made to deflect signal light in response to an electric field applied are arranged in a cascade fashion, and the optical deflecting element constituting the input side deflecting unit or the output side deflecting unit is made so as to variably adjust the level of signal light to be outputted from the output side deflecting unit to the output port.
摘要:
Optical add/drop nodes are used in a network having a pair of optical transmission paths for transmitting optical signals in opposite directions to each other. Each add/drop node comprises a variable split ratio optical coupler for splitting an optical signal output from a transmitter. The split ratio of the variable split ratio optical coupler is set such that the optical power levels of the signals added through the respective optical add/drop nodes are equal to one another respectively on the pair of optical transmission paths.
摘要:
A response-time storing unit stores a response time from start of output of driving force required for switching paths until stabilization of the driving force, for each of the paths to be connected. A driving-force correcting unit corrects output level of the driving force, starting correction of the output level of the driving force after the response time for a specified path stored in the response-time storing unit has passed since output of the driving force required for switching to the specified path started.
摘要:
Provided are a plurality of fixed wavelength drop filters 35 demultiplexing optical signals having a plurality of different fixed wavelengths, a plurality of fixed wavelength add filters 36 provided corresponding respectively to the fixed wavelength drop filters 35 and adding the optical signals having the fixed wavelengths wavelength division multiplexed light flowing along a transmission path 1, a first optical branching unit 31 branching part of the wavelength division multiplexed light flowing along the transmission path 1, and a variable wavelength drop filter 32 demultiplexing the optical signal having the wavelength corresponding to a specified value from the wavelength division multiplexed light branched by the first optical branching unit 31.
摘要:
A phase shift unit provides a prescribed phase difference (π/2, for example) between a pair of optical signals transmitted via a pair of arms constituting a data modulation unit. A low-frequency signal f0 is superimposed on one of the optical signals. A signal of which phase is shifted by π/2 from the low-frequency signal f0 is superimposed on the other optical signal. A pair of the optical signals is coupled, and a part of which is converted into an electrical signal by a photodiode. 2f0 component contained in the electrical signal is extracted. Bias voltage provided to the phase shift unit is controlled by feedback control so that the 2f0 component becomes the minimum.
摘要:
An optical switching device the size and costs of which are reduced by decreasing the number of switching elements and which can flexibly accommodate the expansion of the number of ports. An optical demultiplexing section has 2n (n=1, 2, 3, . . . ) input ports and 2m (m>n) output ports and includes demultiplexing couplers for demultiplexing input optical packets. A switch fabric section includes optical gate elements for switching optical packets outputted from the optical demultiplexing section by switch drive control. An optical multiplexing section has 2m input ports and 2n output ports and includes multiplexing couplers for multiplexing the optical packets which pass through the optical gate elements. A scheduler exercises control over an entire optical packet switching process.
摘要:
An optical packet switching apparatus includes plural optical switches, an optical switching section that switches a path of an optical packet transmitted thereto according to the switch control signal to output the optical packet, and a control section that takes out a header portion representing a destination of the optical packet transmitted, photoelectrically converts the header to generate the switch control signal according to the destination to transmit the switch control signal to the optical switching section and controls the optical switch. The apparatus further includes a light monitor section that monitors a light quantity level of the optical packet transmitted and a light quantity level of the optical packet to be sent out, and an abnormality recognizing section that recognizes an effective timing of monitoring of the light quantity levels based on the switching control signal, and recognizes an abnormality based on the light quantity levels at the timing.