摘要:
In order to be able to use a semiconductor light amplifier of conventional type and operating under gain saturation conditions while nevertheless providing constant gain for an optical signal to be amplified, the device comprises means for producing a compensation light wave and coupling means for injecting the optical signal to be amplified and the compensation light wave into the amplifier. The compensation light wave presents amplitude modulation such that when combined with the optical signal to be amplified the overall amplitude modulation is eliminated or at least attenuated. The device is applicable to optical transmission systems operating at a single wavelength or with wavelength division multiplexing.
摘要:
Packets conveying data are received by a router via input ports which impose on them optical carrier waves whose wavelengths correspond to the ports. Respective time-delays are applied to the packets and they are broadcast to spatial selectors that transmit them to spectral selectors. Amplifiers are distributed over the paths of the packets and the paths are organized in such a manner as to limit the number of semiconductor optical switches in the selectors and to minimize noise and optical crosstalk affecting the packets.
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 communications station (4-i) for a WDM ring network is adapted to insert into an optical fiber (2) packets of optical signals carried by at least one wavelength and having a propagation direction in common with at least one other communications station. The station (4-i) comprises, firstly, optical detection means (17) adapted to observe the traffic in said optical fiber (2) associated with said common wavelength and to deliver detection signals representative of the absence of packets in the optical fiber (2) at the detected wavelength for a duration exceeding a duration threshold and ii) control means (11) adapted, in the event of reception of a detection signal associated with the detected wavelength to determine the remaining time before the end of the current session, and then to instruct the insertion into the optical fiber (2) of a packet awaiting transmission, at the detected wavelength, if the remaining time before the end of the current session is greater than the time necessary for inserting the packet awaiting transmission into the fiber.
摘要:
A communications station (4-i) for a WDM ring network is adapted to insert into an optical fiber (2) packets of optical signals carried by at least one wavelength and having a propagation direction in common with at least one other communications station. The station (4-i) comprises, firstly, optical detection means (17) adapted to observe the traffic in said optical fiber (2) associated with said common wavelength and to deliver detection signals representative of the absence of packets in the optical fiber (2) at the detected wavelength for a duration exceeding a duration threshold and ii) control means (11) adapted, in the event of reception of a detection signal associated with the detected wavelength to determine the remaining time before the end of the current session, and then to instruct the insertion into the optical fiber (2) of a packet awaiting transmission, at the detected wavelength, if the remaining time before the end of the current session is greater than the time necessary for inserting the packet awaiting transmission into the fiber.
摘要:
A WDM network (R) comprises an optical fiber (F) connected to a hub (H) via an input of a demultiplexer (DX) having N outputs to communications stations (Si-Sn) able to deliver and/or receive spectral multiplexes of modulated optical signals with different wavelengths, via coupling means (CP, CP′, MXB). The communications stations (Sn−1) are adapted to deliver spectral multiplexes of modulated optical signals from a given one of P disjoint bands of wavelengths. At least one of the coupling means (MXB) is a 2×1 band multiplexer comprising i) an output connected to a downstream portion of the optical fiber (F), ii) a first input connected to one of the stations (then referred to as the “primary” station) and adapted to its band of wavelengths, and iii) a second input connected to an upstream portion of the optical fiber (F) and adapted to channels having wavelengths different from those of the channels passing through the first input. The demultiplexer (DX) is of periodic type so as to deliver at each of its N outputs channels whose wavelengths belong to distinct sets of P wavelengths each belonging to a distinct one of the P disjoint bands.
摘要:
A device (D) is dedicated to optical switching in a switching node (NC) of a transparent optical network. This device (D) comprises i) at least one input port adapted to be coupled to an upstream optical line (FE1-FE4) dedicated to the transport of multiplexed channels, ii) at least one exit point, iii) switching means (MC) coupling each input port at least to each exit point, and iv) processing means (MT1-MT4) adapted to add to the channels that reach each input port a signature including first information representative of that switching node (NC), and where applicable the input port that received them.
摘要:
A network element (10) comprises: a first optical input section (1), a first optical output section (2), a second optical input section (3) and a second optical output section (4) a first and second insertion and extraction modules (30, 40), each of said insertion and extraction modules comprising a wavelength selection switch (31, 41), a first optical coupler (8) comprising two bidirectional branches (21, 22) respectively connected to the first selectable port of the first and second insertion and extraction modules, and a second optical coupler (11) comprising two bidirectional branches (23, 24) respectively connected to the second selectable port of the first and second insertion and extraction modules.
摘要:
The present invention refers to a method for operating a coherent optical packet receiver comprising at least one linear physical impairment compensation filter wherein the settings of at least one linear physical impairment compensation filter applied on a received optical packet having at least one given travelling parameter are determined in function of previous settings determination of said at least one linear physical impairment compensation filter achieved on at least one optical packet having a similar at least one travelling parameter as said received optical packet.
摘要:
An optical signal switching device comprises a plurality of broadcast couplers (125), a plurality of wavelength selective modules (126), and optical connection means linking outputs of broadcast couplers to inputs of wavelength selective modules in order to route incoming optical signals received by said broadcast couplers to said wavelength selective modules. The wavelength selective modules are arranged in a plurality of groups (117, 118, 119), the wavelength selective modules of one group being connected at the output to a common neighboring node. The optical connection means (127, 41, 40, 42) are configured in such a way as to enable, for each of said broadcast couplers, the broadcasting of the incoming optical signal received by said coupler to at least one wavelength selective module of each group simultaneously.