Abstract: Optical subcarriers may be employed to transmit data in a point-to-multi-point network whereby a hub node including a network switch receives such data from a client and transmits information indicative of such data to multiple leaf or network nodes, where data intended for such leaf node is output. Often the rate at which data is supplied to the hub node is different than the rate at which information indicative of the data is transmitted. Moreover, the client data may have a format that is different than that associated with the transmitted information indicative of the client data. Consistent with the present disclosure, client data is inverse multiplexed to lower data rate streams and then multiplexed to a plurality of inputs, each of which corresponding to a respective optical subcarrier. Information indicative of the data may be allocated to multiple subcarriers, if the a single carrier lacks sufficient capacity or bandwidth to meet the bandwidth requirements of the leaf node.

Abstract: Communication of light signals and optical cables can be managed to mitigate error associated with using optical cables to communicate light signals. A communication management component (CMC) can embed respective timing synchronization pulses in respective lights signals having respective wavelengths. The light signals can be typical light signals or can be squeezed and twisted to generate a desired twisted light signal. The light signals can be transmitted via the optical cable to a receiver. A CMC, at the receiver end, can determine error associated with the transmission of the light signals via the optical cable and respective characteristics of the respective light signals, including respective arrival times of the respective timing synchronization pulses and respective light intensity or power levels of the respective light signals. From the respective characteristics, CMC can determine a compensation action to perform mitigate the error with regard to subsequent transmissions of light signals.

Abstract: Techniques for improving redundancy in semiconductor-based optical communication systems are provided. For example, two or more semiconductor optical amplifiers (SOAs) may be provided in an optical repeater, and each SOA may form a respective amplification path. When failure occurs on a first SOA, a second SOA that is different from the first SOA can be selected. In one example, the selection may be based on wavelength division multiplexing (WDM), and in another example, the selection may be based on optical switching. The two or more SOAs (and other optical components) may be integrated in the same substrate package.

Abstract: Various embodiments for an optical system are described herein. Generally, the optical system may include an optical transmitter coupled to an optical signal transmission path, an optical receiver coupled to an optical signal reception path, and an external signal path extending between an external optical assembly and both the optical signal transmission path and the optical signal reception path. An optical polarization division multiplexer may be provided to couple the optical signal transmission path and the optical signal reception path to the external signal path. A first non-reciprocal polarization rotator may be also positioned along the external signal path between the optical polarization division multiplexer and the external optical assembly. Further, a quarter wave plate may be positioned along the external signal path between the non-reciprocal polarization rotator and the external optical assembly.

Abstract: Implementations described and claimed herein provide systems and methods for an optical domain controller for managing and maintaining a record of network component configuration and interconnections. The optical domain controller detects changes in a configuration of optical network elements in response to a requested service from the network, coordinates additional changes in configurations to optical network elements that may be affected by the detected change, communicates with the optical network elements to incorporate the changes to the configurations of the network element, and stores the configurations and states of the network elements. The use of the optical domain controller may thus replace or supplement a database storing network configuration information by automatically managing changes to the network as new services are instantiated directly on the optical network elements.

Abstract: Communication of light signals and optical cables can be managed to mitigate error associated with using optical cables to communicate light signals. A communication management component (CMC) can embed respective timing synchronization pulses in respective lights signals having respective wavelengths. The light signals can be typical light signals or can be squeezed and twisted to generate a desired twisted light signal. The light signals can be transmitted via the optical cable to a receiver. A CMC, at the receiver end, can determine error associated with the transmission of the light signals via the optical cable and respective characteristics of the respective light signals, including respective arrival times of the respective timing synchronization pulses and respective light intensity or power levels of the respective light signals. From the respective characteristics, CMC can determine a compensation action to perform mitigate the error with regard to subsequent transmissions of light signals.

Abstract: Example methods and apparatus to implement an electrical/optical transceiver to facilitate data transfer are disclosed. An example apparatus includes an electrical transceiver lane to transfer data at a first bandwidth over an electrical link. The example apparatus also includes a plurality of optical transceiver sub-lanes to transfer data over an optical link. The example apparatus also includes a lane switch to dynamically map the electrical transceiver lane to the plurality of optical transceiver sub-lanes based on an analysis of the first bandwidth and the plurality of optical transceiver sub-lanes to accommodate the first bandwidth with at least a subset of the plurality of optical transceiver sub-lanes to transfer data between the electrical link and the optical link.

Abstract: As photonics evolves closer and closer to the electronic processing elements in order to meet the demands of speed, latency of evolving data communications networks and data centers the inventors, rather than seeking direct monolithically integrated CMOS based processing photonic and electronic elements, have established a different route. Namely replace the computer hubs/electrical bridges interconnecting the multiple core logic chipset elements with a photonic bridge. In this manner high risk chip-to-chip photonic point-to-point links are replaced with photonic SOCs that leverage photonics bandwidth density attribute rather than its bandwidth distance attributes. An SOI based Electronic Embedded Photonic Switching Fabric is presented supporting, for example, N×MGb/s interconnections exploiting N channels of MGb/s wherein each channel of exploits S WDM channels of TGb/s. Embodiments of the invention also support high density optical interconnection via vertical grating couplers and multicore fibers.

Abstract: A switchable optical amplifier includes: a first optical amplifier; a second optical amplifier; and an optical switch which includes first and second input ports and first and second output ports, the optical switch that switches between a first connection state where the first input port and the first output port are in an optical connection and the second input port and the second output port are in a no optical connection and a second connection state where the first input port and the second output port are in an optical connection and the second input port and the first output port are in an optical connection, wherein an output of the first optical amplifier is optically coupled to the first input port of the optical switch, an input of the second optical amplifier is optically coupled to the second output port of the optical switch.

Abstract: We disclose an optical buffer having a plurality of optical ports. In some embodiments, an optical signal to be stored may be injected into the buffer through any one of the optical ports and then may be ejected from the buffer, after being stored therein for a selectable amount of time, through any one of the optical ports as well. This feature advantageously enables the optical buffer to also function as an optical switch or router. In an example embodiment, the optical buffer comprises two optical recirculation loops, each of which can store the optical signal by causing it to circulate therein. The buffer is configured to compensate optical losses incurred by the optical signal during this circulation by transferring the optical signal from one loop to the other through an optical amplifier. Due to the latter feature, the optical buffer may be able to store an optical signal, with an acceptable OSNR, for a significantly longer time than certain conventional optical buffers.

Abstract: A device includes a first band coupler, a first reconfigurable optical add-drop multiplexer (ROADM), a second ROADM, and a second band coupler. The first band coupler is configured to decouple a regular band and an extended band. The first ROADM is configured to add or drop one or more frequencies in the decoupled regular band to produce a first output in the regular band. The second ROADM is configured to add or drop one or more frequencies in the decoupled extended band to produce a second output in the extended band. The second band coupler is configured to couple the first output and the second output to produce a third output occupying the regular band and the extended band.

Abstract: An optical fiber transmission distribution assembly, wherein the assembly comprises at least a first splitter having a first split ratio of 1:x (where x is an integer) connected to optical drop cables leading to subscribers, and at least a second splitter having a second split ratio of 1:y (where y is an integer and is different from x), and transfer means whereby an optical drop cable connected to the first splitter can be transferred to receive split optical signals from the second splitter, thereby enabling the signal in the transferred drop cable to be further split by addition of a third splitter at a ratio of 1:p (where p is an integer), to provide p subscriber connection points each having a 1:p*y split ratio at the subscriber end of the transferred drop cable.

Abstract: Techniques for converting signal and idler photons generated by a nonlinear optical system into a deterministic stream of single photons including receiving a heralded, nondeterministic source of signal and idler photons from the nonlinear optical process, separating one or more received signal photons from one or more received temporally corresponding idler photons, determining whether at least one of the one or more signal photons should be variably delayed, and if so, determining a delay length, and variably delaying the emission of one of the one or more signal photons, if any, by the determined delay length.

Abstract: A GPON module comprises a housing and a circuit board disposed in the housing. The circuit board further includes ground lines that substantially isolate regions of the circuit board, an electro-optical interface for converting an inbound optical signal to an electrical signal and processing circuitry that is arranged to provide an electrical RF signal to an RF interface. The RF interface comprises a three-pin RF connector exposed from the housing, wherein the RF connector is coupled directly to the circuit board, and two of the three pins are coupled to ground.

Abstract: A method and apparatus for providing passive optical networks with extended reach and/or splitting ratio are disclosed. For example, the optical network comprises a first optical line termination (OLT) device having a transceiver for sending and receiving optical signals. The optical network further comprises an optical extender box comprising at least one hybrid SOA-Raman amplifier, wherein the optical extender box is coupled to the first optical line termination device via a first standard single mode fiber section. Finally, the optical network further comprises an optical splitter coupled to the optical extender box via a second standard single mode fiber section.

Abstract: A method and apparatus for implementing a hybrid SOA-Raman amplifier in a central office in order to enable multiple passive optical networks to share one or more enhancement service sources, e.g., to share a source for a broadcast service are disclosed.

Abstract: An optical data storage system and method of use thereof are presented. The optical data storage system includes one or more optical buffer modules connected in series. Each optical buffer module includes a cross connect. Each cross connect is connected, by a pair of inputs and outputs, to an optical data storage unit, for example, a fiber delay line, by a pair to either an optical packet network or a cross connect of a first adjacent buffer module in the series, and by a pair to a cross connect of a second adjacent buffer module in the series. The buffer module also includes a read signal output line which is connected to a read signal input line of the second adjacent buffer module for transmitting a read signal. A control module within each buffer module directs the passage of data through the cross connect.

Abstract: An optical signal demultiplexing device includes a demultiplexing unit that receives an optical signal multiplexed by an optical time-division system and a synchronization pattern, and demultiplexes the optical signal based on the synchronization pattern. The optical signal demultiplexing device also includes a pulse-width increasing unit that makes optical signals demultiplexed by the demultiplexing unit generate chirp, and increases the pulse widths of the optical signals generating the chirp by passing the optical signals through a wavelength dispersion medium.

Abstract: A visible light communication (VLC) transceiver and a VLC system are provided. The VLC transceiver includes a substrate, a lens module and a plurality of channel units. The channel units are disposed on the substrate in an array to provide different bidirectional communication channels. Wherein, each of the channel units respectively includes at least a visible light emitter and at least a visible light receiver. The channel units can enhance communication bandwidth by using modulation technology such as spatial multiplexing or time multiplexing. The lens module is disposed on an optical path of the channel units. The lens module actively tracks the receiving situation of the visible light receiver to improve the signal quality of high-speed multiplexing communication.

Abstract: This invention concerns a high frequency optical processor suitable for time-division demultiplexing and channel dropping data signals at bit rates of 80-160 Gb/s and beyond, and for carving high frequency pulse streams with low duty cycle from an unmodulated laser source. In further aspects the invention concerns methods for using the high frequency optical processor. In particular the invention comprises a high frequency optical processor, comprising a Mach-Zehnder amplitude modulator (MZM) embedded in a fiber mirror loop in which the loop input and output are joined by a polarization maintaining coupler.

Abstract: An optical transmission apparatus communicable with a plurality of subscriber including a delay measuring part for detecting a response delay time from each subscriber based on reception timing of the delay measurement response optical packet, a detection part for detecting a received optical level of the delay measurement response optical packet received by the reception part and a state determination part for determining quality of an optical transmission state between the optical transmission apparatus and each subscriber based on the received optical level of the delay measurement response optical packet of each of the plurality of subscribers.

Abstract: An optical signal demultiplexing device includes a demultiplexing unit that receives an optical signal multiplexed by an optical time-division system and a synchronization pattern, and demultiplexes the optical signal based on the synchronization pattern. The optical signal demultiplexing device also includes a pulse-width increasing unit that makes optical signals demultiplexed by the demultiplexing unit generate chirp, and increases the pulse widths of the optical signals generating the chirp by passing the optical signals through a wavelength dispersion medium.

Abstract: An OLT includes a first transmitter and receiver unit for transmitting and receiving signals with ONUs, a first communication control timer, a measurement unit for measuring a round trip time (RTT) between the OLT and each of ONUs, an advance notice time generation unit for generating an advance notice time signal by adding a predetermined time to a time information that indicates a time in the first communication control timer in response to a first time reference pulse, and a unit for controlling the first transmitter and receiver unit to transmit the generated advance notice time signal to each of the ONUs, and to transmit signals indicating measured RTT/2 to the respective ones of the ONUs.

Abstract: An optical network system disclosed in an embodiment of the present invention contains a PE and a handover equipment located between the PE and a CE. The PE is adapted to provide optical network access for the CE. The handover equipment is adapted to disconnect a CE that finishes working at a handover time, and/or connect a PE with a CE that will work in a next time segment. The present invention also discloses a service handover method of optical networks. Furthermore, the present invention discloses a handover equipment and a PE in an optical network. The present invention can reduce the ports occupied by the PE.

Abstract: A dynamic bandwidth allocation method of an Ethernet passive optical network, comprises a predictor and a rule of QoS-promoted dynamic bandwidth allocation (PQ-DBA); the predictor predicts a client behavior and numbers of various kinds of packets by using a pipeline scheduling predictor consisted of a pipelined recurrent neural network (PRNN), and a learning rule of the extended recursive least squares (ERLS); the present invention establishes a better QoS traffic management for the OLT-allocated ONU bandwidth and client packets sent by priority.

Abstract: An OTDM-DPSK signal generator includes an optical splitter, a first and a second phase modulator, an optical coupler, and a monitor signal splitter. The optical splitter splits an optical pulse string into a first and a second optical pulse string. The first and second phase modulators generate a first and a second channel DPSK signal, respectively. The DPSK signals are provided with one bit delay to generate another DPSK signal, which enters the optical coupler, which outputs an OTDM-DPSK signal, which enters a monitor signal splitter. The monitor signal splitter splits from the OTDM-DPSK signal a monitor signal and inputs the monitor signal to an optical carrier phase difference detector. The detector generates an optical carrier phase difference detection signal as a function of an optical carrier phase difference between optical pulses. The optical carrier phase difference can thus be detected between optical pulses in an OTDM-DPSK signal.

Abstract: A modulator includes an electro-optical substrate and a first and second waveguide formed of a doped semiconductor material positioned on a surface of an electro-optical substrate forming a slot therebetween. A doping level of the semiconductor material being chosen to make the first and second waveguide conductive. A dielectric material is positioned in the slot which increases confinement of both an optical field and an electrical field inside the slot. A refractive index of the semiconductor material and a refractive index of the dielectric material positioned in the slot being chosen to reduce the V?·L product of the modulator.

Abstract: The optical time division multiplexer generates a time-division-multiplexed optical signal by time-division-multiplexing optical signals of a plurality of channels, the carrier-wave phases of which are shifted with respect to one another. The circulator guides the multiplexed optical signals split by the optical splitter to the optical interference device and the superimposed light outputted from the optical interference device is guided to the optical intensity detector. The optical interference device extends the pulse width of the multiplexed optical signal to a width equal to or more than the bit interval and superimposes the extended light of an adjacent bit onto the extended light. The optical intensity detector detects the intensity of the superimposed light outputted by the optical interference device. The temperature regulator controls the temperature of the modulator so that the phase difference of the carrier waves constituting the optical signal trains is to be a half wavelength.

Abstract: Regarding the passive optical network (PON) system of the present invention, in an OLT, data of different bit rates is framed, and framed data rows are subjected to FEC encoding processing without changing the line up of the data, and a check bit is added to the end of the frame, and an optical signal that has been modulated in accordance with the data row to which the check bit has been added is transmitted to the optical transmission line. Then in an ONU that corresponds to a high speed bit rate to which an optical signal from the OLT has been applied via a power splitter, forward error correction of the reception data is performed. As a result in a PON system in which data of different bit rates coexist, the minimum reception rate of a high speed ONU can be improved without having an influence on a low speed ONU.

Abstract: In an optical element integrated module, first through n-th optical data signals are externally input to first ports of first through n-th optical circulators and are input to first through n-th optical/optical converters via second ports. The first through n-th optical/optical converters modulate first through n-th optical short pulse trains in accordance with the first through n-th optical data signals. First through n-th modulated optical data signals are input to the second ports of the first through n-th optical circulators and are input to an optical time division multiplexing section. The optical time division multiplexing section generates optical time division multiplexed signals by time division multiplexing the first through n-th modulated optical data signals.

Abstract: A method of extracting a predetermined channel from an OTDM signal includes the steps of combining at the inlet of an SOA the OTDM signal and an impulsive signal with impulses temporally synchronized with the channel to be extracted to produce in the SOA FWM, XGM and XPM effects which shift to a length c the channel chosen for extraction with c outside the length d of the OTDM signal with the other channels outlet from the SOA and filtering the SOA outlet to extract components with c d that represent respectively the desired channel and the cleaned OTDM signal. A multiplexer in accordance with the method includes an inlet (14) of an OTDM signal sent to an SOA (24) together with an appropriate impulsive signal. The SOA outlet is filtered by filters (28, 29) to obtain the signal of the extracted channel (16) and the cleaned OTDM signal (15).

Abstract: In a conventional network for transmitting an optical burst signal, it is impossible to effectively swap labels, reproduce a payload signal, and switch and transmit the signals.

Abstract: The invention relates to a device and a method for converting WDM signals into an OTDM signal. The device comprises shifting means (102, 103, 104) adapted to introduce a time shift between the pulses of the WDM signals carried by the optical carriers, modulation means (112, 113, 114) adapted to modify the optical power of the WDM signals, an optical temporal multiplexer/demultiplexer (120), a birefringent propagation medium (130) into which the WDM signals are injected in such a manner as to achieve a soliton trapping phenomenon, and absorption means (140) adapted to introduce optical losses into the components of the OTDM signal. This device performs WDM/OTDM conversion at very high bit rates. It also performs OTDM/WDM conversion. It is intended to be installed in long-haul telecommunication networks.

Abstract: A method and system for ensuring confidentiality of signal transmission in a point-to-multipoint data transmission network like Ethernet passive optical network, including at least one hub, at least one transmission medium and at least one station connected to the hub via the transmission medium. When an upstream signal is transmitted from a first station, the upstream signal is reflected by at least one disturbing reflector for producing a disturbing reflection. The disturbing reflection combines with a second reflection of the upstream signal and renders the second reflection undecodable by a second station.

Abstract: An optical packet network system of a ring type, capable of preventing degradation of an optical signal, can be implemented by providing a mechanism relatively simple in structure, capable of erasing light noise if the optical packet signal does not exists. In the optical packet network system made up by interconnecting respective nodes adjacent to each other, and connecting a sending source of an optical packet signal to a ring, a light noise removal function block is provided between the respective nodes adjacent to each other.

Abstract: An OTDM transmitting method and transmitter realizing an OTDM distortion-free transmission substantially not relying upon dispersion. A time division multiplexed OTDM signal from an OTDM signal transmitter (1) enters an optical Fourier transform unit (2). Optical Fourier transform can be carried out most accurately so long as the optical pulse is a chirp-free Fourier transform limit pulse. The optical Fourier transform unit (2) converts the time waveform of the pulse into a signal on the frequency axis, and an optical inverse Fourier transform unit (2?) converts a spectral shape on the frequency axis into a time waveform (pulse). An optical fiber transmission line (3) is a transmission line having an arbitrary dispersion and a polarization mode dispersion. These dispersions may involve a time variation. An OTDM signal receiver (4) demultiplexes a transmission signal into low-speed optical signals, in a light region, receives optical pulses for respective channels and converts them into electric signals.

Abstract: An apparatus detecting an optical carrier phase difference between adjacent optical pulses structuring an OTDM-DPSK signal, by generally-used optical and electrical elements, is provided. An OTDM-DPSK signal generating section has an optical splitter, a first phase modulator, a second phase modulator, an optical coupler, and a monitor signal branching device, and generates and outputs an OTDM-DPSK signal and a monitor signal. An optical carrier phase difference detecting section has an optical carrier interferometer, and an interference signal detecting section including a optical-to-electrical converter and a peak detection circuit. The monitor signal is inputted to the optical carrier interferometer, and an interference monitor signal is outputted. The interference monitor signal is inputted to the optical-to-electrical converter, and an electrical interference monitor signal is outputted.

Abstract: A method for transmission of multiple, independent data packages across a single optical fiber utilizing both time division multiplexing and wavelength division multiplexing is described. The method includes transmitting a first data package across the single optical fiber at a first wavelength and transmitting a second data package across the same optical fiber at a second wavelength, in either the same direction or in a direction opposite as the first data package, wherein the second data package transmission may be concurrent with the first data package transmission. the method further includes separating the data package transmissions into two optical paths, filtering the second wavelength from a first of the two optical paths, detecting the first data package at the first wavelength, filtering the first wavelength from a second of the two optical paths, and detecting the second data package data at the second wavelength.

Abstract: A method and system for ensuring confidentiality of signal transmission in a point-to-multi point data transmission network like Ether net passive optical network, including at least one hub, at least one transmission medium and at least one station connected to the hub via the transmission medium. When an upstream signal is transmitted from a first station, the upstream signal is reflected by at least one disturbing reflector for producing a disturbing reflection. The disturbing reflection combines with a second reflection of the upstream signal and renders the second reflection undependable by a second station.

Abstract: An optical fiber communications apparatus comprises a housing provided with a motherboard and with a support defining plurality of card receptors. A plurality of modular cards (12, 13) are provided, each of which is engageable with the motherboard via one of the card receptors. A optical card (12) includes an optical transceiver (20) for communication using a digital, optical communications signal over a single optical fiber link (17). Each modular card (12, 13) is provided with a plurality of circuit sub-assemblies (16), each circuit sub-assembly being configured for digital communication with a respective local audio, video or data electronic device via a respective connector using a respective electronic information-carrying signal. Each circuit sub-assembly (16) is configured for communication of an audio, video or data information-carrying signal with the transceiver using the digital, optical communications signal.

Abstract: Amplitude modulation is performed for a signal light with a modulation signal having the same cycle as that of an optical pulse to be extracted by using an optical modulator. At this time, timing is adjusted so that the peak of the optical pulse of the channel to be extracted of the signal light becomes the largest. A spectrum of the amplitude-modulated signal light is expanded according to the size of the peak of the optical pulse by a spectrum expander. Then, part of the expanded spectrum is extracted with a band pass filter, whereby the optical pulse of the desired channel is extracted.

Abstract: A device and a method for converting WDM signals into an OTDM signal. A time shift is introduced between the pulses of the WDM signals carried by the optical carriers. A modulation means is (112, 113, 114) adapted to modify the optical power of the WDM signals, and an optical temporal multiplexer/ demultiplexer (120) is provided. The WDM signals are injected into a birefringent propagation medium (130) in such a manner as to achieve a soliton trapping phenomenon. An absorption means (140) is adapted to introduce optical losses into the components of the OTDM signal. This technique performs WDM/OTDM conversion at very high bit rates. It also performs OTDM/WDM conversion. It is intended to be installed in long-haul telecommunication networks.

Abstract: An Ethernet passive optical network provides a subscriber with a high speed and large capacity data service and a real time digital broadcast/video service. The network includes an optical line terminal for frame-multiplexing broadcast/video signals, which are obtained by performing a switching operation and a time-slot multiplexing with respect to a plurality of digital broadcast/video data delivered from external broadcasting vendors according to broadcast/video selection information delivered from each user, and communication data delivered through an Internet protocol network.

Abstract: An optical modulator using a thin plate including a portion having 20 ?m or less thickness, capable of selecting a specific polarized wave from a light wave which propagates in an optical waveguide in the modulator without reduced productivity. The modulator includes an X-cut or Y-cut thin plate of a material having an electrooptic effect; an optical waveguide formed in a top or bottom surface of the plate; and a control electrode on the top surface of the plate to modulate light which propagates in the waveguide. An attenuating means which absorbs light having a specific polarization plane of a light wave which propagates in the waveguide is disposed in the vicinity of the waveguide. The attenuating means includes light absorbing members disposed at a gap L which is 0.5 to 2 times the mode-field diameter of the light wave which propagates in the waveguide with the waveguide interposed therebetween.

Abstract: An optical power converting apparatus is provided that may be used with remote sensors. A plurality of remote sensors may be coupled to a backbone optical fiber with each sensor having an optical power converter that receives an optical signal from a head end of that fiber. The optical power converters may store electrical energy derived from that optical signal and use that energy to power the remote sensors. The head end's optical signal may also include a clock signal, and each remote sensor may be set to sense a measurable parameter after a given number of clock cycles have been counted. In a further example, each of the optical sensors may be synchronized before counting these clock signals via a synchronization signal from the optical power converter. The remote sensors may individually and separately uplink their sensed data to the head end on the optical fiber. The apparatus may be implemented in a vehicle health management system, for example.

Abstract: An OTDM-DPSK signal generator includes an optical splitter, a first and a second phase modulator, an optical coupler, and a monitor signal splitter. The optical splitter splits an optical pulse string into a first and a second optical pulse string. The first and second phase modulators generate a first and a second channel DPSK signal, respectively. The DPSK signals are provided with one bit delay to generate another DPSK signal, which enters the optical coupler, which outputs an OTDM-DPSK signal, which enters a monitor signal splitter. The monitor signal splitter splits from the OTDM-DPSK signal a monitor signal and inputs the monitor signal to an optical carrier phase difference detector. The detector generates an optical carrier phase difference detection signal as a function of an optical carrier phase difference between optical pulses. The optical carrier phase difference can thus be detected between optical pulses in an OTDM-DPSK signal.

Abstract: A method of wavelength selection control is disclosed.

Abstract: To resolve problems, with the invention, an optical transmitter comprises an encoder for generating an optical signal obtained by encoding multi-wavelength pulses corresponding to sending data by use of a method of time spread/wavelength hopping in accordance with an encoding pattern of the encoder itself. The encoder concurrently executes time delay for every wavelength component at encoding, and time delay due to pre-compensation processing to pre-compensate for difference in propagation time for every wavelength component, occurring due to chromatic dispersion characteristics of a transmission line by ?%. An optical receiver comprises a decoder for decoding the optical signal transmitted by the optical transmitter in accordance with a decoding pattern of the decoder itself.

Abstract: An electro-optical device includes a first electro-optical element, a second electro-optical element, and a third electro-optical element. A first node is electrically connected to the first electro-optical element, a second node is electrically connected to the second electro-optical element, and a third node electrically connected to the third electro-optical element. A first resistor placed between the first node and the third node and a second resistor placed between the second node and the third node. Additionally, a first signal supplying unit that supplies a first signal to the first node and a second signal supplying unit that supplies a second signal to the second node.

Abstract: A chassis includes a plurality of slots to receive modules. The chassis includes an electrical backplane to couple to a module received in a first slot of the plurality of slots. The module to couple via a first communication interface on the module. An optical backplane is also included in the chassis. The optical backplane is to couple to the modules via a second communication interface on the module. The optical backplane is to couple to the second interface on the module via at least one interconnect through an opening in the electrical backplane. The interconnect configured to couple a fabric interface associated with the second communication interface to a communication channel routed over the optical backplane.