摘要:
An optical packet node for receiving and transmitting optical packets is disclosed. A multiwavelength band splitting device splits received optical packets transmitted via multiwavelength bands into at least three groups, each group including one multiwavelength band. A multiwavelength band combining device combine the three groups of multiwavelength bands. At least two optical packet add drop multiplexers are placed between the multiwavelength band splitting device and the multiwavelength band combining device. Each optical packet add drop multiplexer adds and drops at least one individual wavelength to a respective multiwavelength band group. A load balancing stage is connected to the optical packet add drop multiplexers to provide an interconnection between at least two wavelength bands.
摘要:
The field of the invention is that of switching optical signals with carrier wavelength conversion capacity, comprising a set of input ports (PE1-PEn), a set of output ports (PS1-PSn) functionally connected to the input ports so that an input signal presented to one of the input ports may be selectively routed to at least one of the output ports, and wavelength conversion means (34) providing a capacity for converting an input signal carrier wavelength to at least one other output port output wavelength.According to the invention the wavelength conversion capacity of said conversion means (34) is limited by at least one of the following three limitation means i) to iii): i) for at least one of said output ports (PS), no wavelength conversion may be applied for sending a signal from an input port; ii) for at least one of said output ports (PS), wavelength conversion may be applied for sending a signal from an input port (PE), but to only a restricted number of wavelength values from the number L of different wavelength values accepted at the input, this restricted number being greater than 0 and less than L, and iii) for only a restricted number of output ports (PS) less than the total number of output ports of the switching system, wavelength conversion may be applied for sending a signal from an input port (PE) to any wavelength value from the number L of different wavelength values accepted at the input.
摘要:
The invention relates to a switch (112) for optical signals and which has a number of outputs at least equal to the number of inputs and include means whereby an input signal is routed to at least one of those outputs. Each input receives information modulating optical carriers at different wavelengths. The switch (112) includes means (12611, 12612, . . . , 126NB) for grouping all the carriers received into non-contiguous subsets of carriers (G11, . . . , G1B, . . . , GN1, . . . , GNB) and means (1291, 1292, . . . , 129NB) for selecting blocks of carriers from the same subset of carriers. The information corresponding to each subset of optical carriers is thus routed in blocks to the same subset output. Switching the carriers at the subset level improves the quality of the output signal and limits the number of components for the same total quantity of information switched.
摘要:
A device for reducing time distortion generated in light pulses by an optical frequency converter including at least one nonlinear optical component (4) having a nonlinear optical susceptibility χ of about 2 or 3, the converter being capable of receiving at least one incident pulse light beam (2), the incident light pulses having a duration Δt0, an optical frequency ω0±Δω0 and an intensity I0(t), and of generating, by frequency conversion, at least one output pulse beam (3), the output light pulses having a duration Δt1, an optical frequency Δ1±Δω1 different from ω0±Δω0, and an intensity I1(t). The time distortion-reducing device includes a pre-compensation linear time filter (5) provided on the path of the incident beam (2), and capable of reducing the intensity time distortions generated in the frequency-converted output light pulses to at least one pre-compensation intensity Icomp.
摘要:
The invention concerns a polarization-maintaining fiber-optic transmission system. The invention concerns a fiber-optic transmission system comprising at least one polarization maintaining fiber coupling an input device to an output device. The fiber comprises at least a first (F1) and a second (F2) polarization maintaining fiber section having each a slow propagation axis and a fast propagation axis. One end of the first fiber section is coupled to one end of the second fiber section such that the slow propagation axis of the first fiber section coincides with the fast propagation axis of the second fiber section and inversely. The invention is applicable in particular to lasers.
摘要:
A selective frequency extractor is disclosed which forwards one or more selected frequencies of a wavelength division multiplex input signal consisting of N channels to one output port and all the other frequencies to another output port. A reconfigurable frequency add and drop multiplexer is also disclosed. The input signal is divided up by a first demultiplexer and routed to a plurality of interleaved stages of optical switches for selectively feeding a plurality of input ports of a multiplexer, whose routing properties are then used for extracting one or more frequencies from the input signal or for reconfigurable frequency add and drop multiplexing.
摘要:
A method and a device for compensating the polarization mode dispersion (PMD) of a transmitted optical signal comprise means of a polarization controller (3) coupled to a differential group delay (DGD) generator (5). The polarization controller (3) is controlled by a feedback loop, said feedback loop implementing an optimisation algorithm to optimize a feedback parameter of the output signal of the DGD generator (5). The algorithm takes into account the state of polarization (SOP) of an optical signal determined from the output signal of the polarization controller (3)) or from the output signal from the DGD generator (5).
摘要:
A method for spreading a spectrum of a narrowband signal, e.g. a monochromatic optical signal or a radiofrequency carrier. The method uses a phase modulation using a modulation signal that includes a plurality of sinusoidal components, the plurality including a component at a fundamental frequency and at least one component at a frequency that is a harmonic of the fundamental frequency, the sinusoidal components being synchronous and affected with phases respectively equal to consecutive multiples of π/2.
摘要:
The present invention relates to an optical communication network and to a network element for use in such a network. The network element comprises a plurality of receivers (70-76) for receiving optical communication signals, a plurality of transmitters (54-62, 82-86) for transmitting optical communication signals, and a plurality of network connections, each network connection having an individual signal impairment characteristic. The pluralities of receivers (70-76) and transmitters (54-62, 82-86) are adapted to employ a plurality of different modulation schemes (64, 66). Furthermore, the pluralities of receivers (70-76) and transmitters (54-62, 82-86) are assigned to the network connections as a function of the individual signal impairment characteristics.
摘要:
A decision system for a modulated electrical signal delivered by a converter in response to a received modulated optical signal compares the amplitude of the electrical signal to a reference level, measures an average amplitude of the electrical signal, and generates the reference level as a function of the result of such measurements so that the “reference level/average amplitude” ratio can be adjusted to a predetermined constant value different from 1. Applications include receivers for optical packet transmission systems.