Abstract: Optical network systems are disclosed, including systems having transmitters with a digital signal processor comprising forward error correction circuitry that provides encoded first electrical signals based on input data; and power adjusting circuitry that receives second electrical signals indicative of the first electrical signals, the power adjusting circuitry supplying third electrical signals, wherein each of the third electrical signals is indicative of an optical power level of a corresponding to one of a plurality of optical subcarriers output from an optical transmitter.

Abstract: Proposed are an optimal operation method of a high-frequency dithering technique for compensating for interference noise in an analog optical transmission-based mobile fronthaul network, and a transmitter using same. An interference noise compensation method using high-frequency phase dithering performed in an analog optical transmission-based mobile fronthaul network may include the steps in which: a frequency-multiplexed wireless signal is converted in an optical transmitter to an intensity-modulated optical signal; and the phase of the optical signal intensity-modulated in the optical transmitter is dithered with an Orthogonal Frequency-Division Multiplexing (OFDM) signal.

Abstract: An optical device includes a first waveguide, ring-shaped waveguides adjacent to the first waveguide, and heaters coupled to the ring-shaped waveguides in one-to-one correspondence. A method includes coupling a first light source with a first wavelength to the first waveguide, increasing electric current through the heaters until a first one of the ring-shaped waveguides resonates, assigning the first one of the ring-shaped waveguides to the first wavelength, resetting the electric current through the heaters to the initial electric current, coupling a second light source with a second wavelength to the first waveguide wherein the second wavelength is different from the first wavelength, increasing the electric current through the heaters until a second one of the ring-shaped waveguides resonates wherein the second one of the ring-shaped waveguides is different from the first one of the ring-shaped waveguides, and assigning the second one of the ring-shaped waveguides to the second wavelength.

Abstract: A lighting and communication system includes a first optical fiber portion, a second optical fiber portion, a third optical fiber portion, a fourth optical fiber portion and a fifth optical fiber portion that are distinct, wherein a visible light transmitter is positioned at a first end of the first optical fiber portion, a modulated light signal transmitter is positioned at a first end of the second optical fiber portion, a second end of the first optical fiber portion and a second end of the second optical fiber portion are connected to a first end of the third optical fiber portion, a modulated light signal receiver is positioned at a first end of the fourth optical fiber portion, a second end of the third optical fiber portion and a second end of the fourth optical fiber portion are connected to a first end of the fifth optical fiber portion.

Abstract: In order to readily carry out communication between terminal stations, a submarine optical communication system includes a first terminal station including a first monitoring means for monitoring the signal quality of dummy light a first dummy light source that outputs dummy light to the second terminal station, and a first light transmitting means for transmitting an optical signal to the second terminal station, the optical signal including a first signal quality of the dummy light; and the second terminal station including a second dummy light source that outputs dummy light to the first monitoring means, a second monitoring means for monitoring the signal quality of the dummy light, and a light receiving means for receiving the optical signal.

Abstract: An optical signal adjustment unit (1) is configured in such a way that optical signals with different wavelengths are input thereto, and adjusts an intensity of each optical signal based on an intensity change in a transmission line, and outputs the optical signals. A dummy light output unit (2) outputs dummy lights (D) with different wavelengths, each dummy light having an intensity based on an intensity change in a transmission line. A control unit (4) identifies the dummy light corresponding to each optical signal, and controls the intensity of the identified dummy light based on the intensity of the optical signal corresponding to the identified dummy light and output from the optical signal adjustment unit (1). A multiplexing unit (3) outputs a wavelength-multiplexed optical signal (L) where the dummy light (D) and the optical signal (L10) output from the optical signal adjustment unit are combined.

Abstract: Multi-level beam scheduling in a wireless communications circuit, particularly for a wireless communications system (WCS), is disclosed. The WCS includes a central unit(s) and a wireless communications circuit(s) configured to reduce beamforming overhead and improve radio frequency (RF) coverage in a wireless communications cell(s) based on a multi-level beam scheduling scheme. In a non-limiting example, the multi-level beam scheduling scheme includes a first level (L1) scheduler, a second level (L2) scheduler, and a third level (L3) scheduler configured to perform cross-cell beam scheduling, in-cell beam scheduling, and in-beam user equipment (UE) scheduling, respectively. By employing the multi-level beam scheduling scheme in the WCS, it may be possible to reduce processing overhead and improve resource usage, data throughput, and system adaptability of the wireless communications circuit(s), thus helping to optimize capacity and throughput in the wireless communications cell(s).

Abstract: A butterfly-type packaged optical transceiver with multiple transmission and reception channels includes a box-shaped housing, a cover plate, an optical receiving module, an optical emitting module, a polarizing prism module, an optical fiber connector and electrical connection elements. The sealed housing encloses the optical receiving module, the optical emitting module, and the polarizing prism module. Electrical connection elements penetrate both side surfaces of the housing and are in contact with the optical fiber connector and the optical receiving module and the optical emitting module. A first incoming optical signal is transmitted to the optical receiving module via the optical fiber connector, the through hole, and the prism module, and the optical emitting module emits an outgoing second optical signal through the prism module, the through hole, and the optical fiber connector.

Abstract: Systems and methods for increasing throughput of a photonic processor by using photonic degrees of freedom (DOF) are provided. The photonic processor includes a multiplexer configured to multiplex, using at least one photonic DOF, multiple encoded optical signals into a multiplexed optical signal. The photonic processor also includes a detector coupled to an output of an optical path including the multiplexer, the detector being configured to generate a first current based on the multiplexed optical signal or a demultiplexed portion of the multiplexed optical signal. The photonic processor further includes a modulator coupled to and output of the detector, the modulator being configured to generate a second current by modulating the first current.

Abstract: Systems and methods for calibrating a Raman amplifier in a photonic line system of an optical network are provided. A method, according to one implementation, includes the step of setting the gain of a plurality of pump lasers of a Raman amplifier to a safe level. For example, the pump lasers are configured to operate at different wavelengths. Also, the Raman amplifier is connected to a fiber span having a specific fiber-type. The safe can be defined as a level that keeps adverse intermodulation effects below a predetermined threshold regardless of the specific fiber-type. In addition, the method includes the step of increasing the gain of the pump lasers without prior knowledge of the specific fiber-type of the fiber span while keeping the adverse intermodulation effects below the predetermined threshold.

Abstract: A measurement apparatus comprising a first terminal to receive an input signal of a circuit under test; a second terminal to receive an output signal of the circuit under test. A first and second phase splitter configured to generate a first and second phase signal, I1 and I2, and a first and second quadrature signal, Q1 and Q2. A first and second multiplexer, each coupled to the first terminal and the second terminal and configured to alternately pass the input and output signals of the circuit under test to the inputs of the first and second phase splitters. A double-quadrature mixer having four inputs configured to receive I1, Q1, I2, and Q2, and an output. A calculation unit to determine one or both of a phase shift of the circuit under test and/or a gain of the circuit under test based on the output of the double-quadrature mixer.

Abstract: An optical transmitter (and methods of transmitting and receiving) includes a delay and modulation circuit configured to receive at least one optical beam and a first data signal (persistent data) and generate at least two or more modulated optical beams having the first data encoded therein. One of the modulated optical beams is a time-delayed or time-shifted version of another one of the modulated optical beams, and both beams are directed toward a target. The amount or time delay between the first and second optical beams can be modulated according to a second data signal (non-persistent data) to encode the second data therein. An optical receiver is configured to detect the two modulated optical beams and recover the first data.

Abstract: A method, system and apparatus for optimizing parameters between two optical coherent transceivers connected via an optical link, including determining performance of a second optical receiver; wherein the second optical transceiver uses a set of parameters; and inputting information into a side channel communication between a first optical transceiver and the second optical transceiver to update the set of parameters for the second transceiver.

Abstract: A surgical laser system includes an array of laser diodes that are configured to output laser energy, a fiber bundle, a delivery fiber, and a tubular sheath. The fiber bundle includes a plurality of optical fibers and has a proximal end that is configured to receive laser energy from the array of laser diodes. The delivery fiber includes a proximal end that is configured to receive laser energy from a distal end of the fiber bundle. The tubular sheath defines a lumen, in which at least a portion of the delivery fiber is disposed. The tubular sheath is insertable into a working channel of an endoscope or a cystoscope. A distal end of the tubular sheath is configured to deliver laser energy discharged from the delivery fiber into a body of a patient.

Abstract: A three-dimensional surface display device that includes a plurality of light-emitting elements that are mounted on a mounting member is disclosed. The three-dimensional surface display device includes a plurality of light guide portions, each of which includes a light incidence surface on one end side and a light extraction surface on the other end side. The light incidence surface is arranged to face the corresponding light emitting element. The plurality of light guide portions are different in at least one length, and the light extraction surfaces are arranged three-dimensionally adjacent to each other.

Abstract: A method of tuning optoelectronic transceivers in an optical network may include powering on an optoelectronic transceiver, setting the channel wavelength of the optoelectronic transceiver, transmitting a request command from the optoelectronic transceiver through the optical network to another optoelectronic transceiver; and waiting to receive a second request command from the another optoelectronic transceiver.

Abstract: Systems and Methods are disclosed for providing measurement data redundancy to intelligent electronic devices (IEDs) in an electric power system, without additional redundant components. In various embodiments, a first measurement device obtains measurement data from a first portion of the electric power delivery system. A second measurement device obtains measurement data from a second portion of the electric power delivery system. A first IED monitors the first portion of the electric power delivery system based on measurement data associated with the first portion of the electric power delivery system, and a second IED monitors the second portion of the electric power delivery system based on measurement data associated with the second portion of the electric power delivery system.

Abstract: An optical transmitter includes photonic integrated circuits configured to respectively output optical transmission signals in different wavelength ranges. A photonic integrated circuit may include emitters configured to emit beams having different wavelengths; drivers configured to respectively provide power to the emitters, and a wavelength division multiplexer configured to transmit the beams emitted by the emitters. A photonic integrated circuit may include a switch device that controls the drivers, and light detectors configured to detect intensities of the beams emitted from the emitters. The switch device may selectively operate at least one driver of the plurality of drivers based on information associated with intensities of the beams. The switch device may selectively operate a driver connected to an emitter, based on a determination that an intensity of a beam emitted by another emitter is less than a threshold intensity value.

Abstract: An optical remodulator includes: a polarization diversity modulator configured to modulate an input optical signal to generate an output optical signal by using a first optical modulator implemented for a first polarization state and a second optical modulator implemented for a second polarization state that is orthogonal to the first polarization state; a photo detector configured to optical-to-electrical convert the input optical signal or the output optical signal or both of the optical signals into an electric signal; and a drive signal generator configured to generate a first drive signal that drives the first optical modulator and a second drive signal that drives the second optical modulator based on the electric signal generated by the photo detector.

Abstract: An optical path for transmission of data from a source node to a destination node comprises an optical channel for parallel transmission of non overlapping carrier frequencies. The frequency separation of the carriers is lower than the baud rate. The optical path is configured by (a) determining a path OSNR (OSNRp ); (b) selecting a carrier bandwidth (BW) so that the channel bandwidth (BWT ) is less than or equal to a maximum path bandwidth available for transmission, wherein BWT?BW·C, wherein C is the number of carrier frequencies; (c) selecting a FEC code having a minimum overhead requirement; (d) determining a channel OSNR (OSNRT ) based on the currently selected BW and FEC code; (e) in response to determining that OSNRT is not less than or equal to OSNRp, reselecting new codes having increasing overhead requirements until OSNRT is less than OSNRp, and if this is not possible increasing BWT and returning to step (c); (h) configuring the path for transmission based on the finally selected BWTand FEC code.

Abstract: The present invention discloses a method for detecting influence on a laser from back-reflected light of the laser and a detection device.

Abstract: An integrated apparatus with optical/electrical interfaces and protocol converter on a single silicon substrate. The apparatus includes an optical module comprising one or more modulators respectively coupled with one or more laser devices for producing a first optical signal to an optical interface and one or more photodetectors for detecting a second optical signal from the optical interface to generate a current signal. Additionally, the apparatus includes a transmit lane module coupled between the optical module and an electrical interface to receive a first electric signal from the electrical interface and provide a framing protocol for driving the one or more modulators. Furthermore, the apparatus includes a receive lane module coupled between the optical module and the electrical interface to process the current signal to send a second electric signal to the electrical interface.

Abstract: Pairs of distributed feedback (DFB) lasers are provided on a substrate. An arrayed waveguide grating (AWG) is also provided on the substrate having input waveguides, each of which being connected to a corresponding pair of DFB lasers. The wavelengths of optical signals supplied from each pair of DFB lasers may be spectrally spaced from one another by a free spectral range (FSR) of the AWG. By selecting either a first or second DFB laser in a pair and temperature tuning to adjust the wavelength, each pair of DFB lasers can supply optical signals at one of four wavelengths, pairs of which are spectrally spaced from one another by the FSR of the AWG. A widely tunable transmitter may thus be obtained.

Abstract: An optical add-drop multiplexer having first and second routes includes: an optical cross connect; a first multiplexer optically coupled to a plurality of output ports of the optical cross connect; a second multiplexer optically coupled to a plurality of other output ports of the optical cross connect; a first wavelength selective switch to generate a first WDM optical signal including an optical signal output from the first multiplexer and to guide the first WDM optical signal to the first route; and a second wavelength selective switch to generate a second WDM optical signal including optical signal output from the second multiplexer and to guide the second WDM optical signal to the second route.

Abstract: A transmitter for transmitting an optical signal based on a baseband signal, including an up-transformer for up-transforming the baseband signal to obtain a bandpass signal and a converter for converting the bandpass signal into a signal having a DC-offset. The transmitter further includes a modulator for modulating a light source with the signal having the DC-offsets to transmit the optical signal.

Abstract: An optical transmission device that receives a wavelength division multiplexed optical signal obtained by dividing an optical packet signal and performing wavelength multiplexing and that transmits via an optical switch the received wavelength division multiplexed optical signal includes an optical power level measurement unit configured to measure respective optical power levels of respective optical signals of wavelengths included in the wavelength division multiplexed optical signal, and a routing information determinator configured to determine routing information of the wavelength division multiplexed optical signal on the basis of the measured optical power levels.

Abstract: Detection and characterization of laser clipping within communication devices. Identification of one or more harmonics associated with a fundamental frequency by which signaling is effectuated within the communication system for laser clipping identification. Appropriate spectral signal analysis is made to identify the presence of characteristic(s) (e.g., energy, amplitude, phase, and/or other characteristic(s)), if any, at one or more harmonic frequencies within a received signal. Appropriate time correlation is performed to distinguish whether or not characteristic(s) associated with at one or more of these harmonic bands is a result of laser clipping or from some other source (e.g., such as other signals within a communication system that happened to reside at those respective harmonic bands). Such appropriate identified correlation between characteristic(s) corresponding to a fundamental frequency band of the communication signal and characteristic(s) corresponding to one or more harmonics (e.g.

Abstract: An optical module that outputs a wavelength multiplexed optical signal is disclosed. The optical module provides at least first to third optical source, a wavelength multiplexer, a polarization rotator, and a polarization multiplexer. The optical sources each outputting first to third optical signals with a wavelength different from others. The wavelength multiplexer multiplexes the first optical signal with the third optical signal. The polarization rotator rotates the polarization vector of one of the multiplexed first and third optical signals and the second signal by substantially 90°. The polarization multiplexer multiplexes the polarization rotated optical signal with the second optical signal.

Abstract: The present invention relates to an optical communication module, which includes: a first bidirectional multiplexer; a second bidirectional multiplexer; an optical fiber for connecting the first bidirectional multiplexer and the second bidirectional multiplexer to each other; one or more first light emitting devices connecting to the first bidirectional multiplexer, and operating in a first light emitting wavelength band; one or more first light receiving devices connecting to the first bidirectional multiplexer, and operating in a first light receiving wavelength band; one or more second light receiving devices connecting to the second bidirectional multiplexer, and operating in a second light receiving wavelength band; and one or more second light emitting devices connecting to the second bidirectional multiplexer, and operating in a second light emitting wavelength band.

Abstract: An apparatus includes an array of lasers, an array of electrical drivers, and optical filter. Each laser is configured to produce light in a corresponding wavelength-channel, wherein the wavelength-channels of different ones of the lasers are different. The electrical drivers are connected to directly modulate the lasers. Each driver produces a first driving current or voltage to cause a corresponding one of the lasers to be in a first lasing state and produces a different second driving current or voltage to cause the corresponding one of the lasers to be in a different second lasing state. The optical filter is connected to receive light output by the lasers. The optical filter selectively attenuates light from each of the lasers in the first lasing states thereof and to selectively pass light from each of the lasers in second lasing states thereof.

Abstract: Wavelength-based optical power provisioning is provided by multiplexing a plurality of continuous wave light beams at different wavelengths onto a single optical fiber as a multiplexed light source and demultiplexing the multiplexed light source based on wavelength at a photonic unit coupled to the optical fiber to recover the continuous wave light beams. The recovered continuous wave light beams are split into a plurality of light beams by the photonic unit, each light beam having the same wavelength and the same or lower power as one of the recovered continuous wave light beams so that at least one of the light beams generated by the photonic unit has a higher power than the other light beams generated by the photonic unit.

Abstract: A multi-laser transmitter optical subassembly may include N number of lasers, where each laser is configured to generate an optical signal with a unique wavelength. The transmitter optical subassembly may further include a focusing lens and a filter assembly. The filter assembly may combine the optical signals into a combined signal that is received by the focusing lens. The filter assembly may include N?1 number of filters. Each of the filters may pass at least one of the optical signals and reflect at least one of the optical signals. The filters may be low pass filters, high pass filters, or a combination thereof.

Abstract: A method, an apparatus, and a computer program product for wireless communication are provided. The apparatus receives a first message from a first wireless communication device and a second message from a second wireless communication device, obtains information associated with a first processing delay with respect to the first message and a second processing delay with respect to the second message, and transmits a third message comprising an indication of the information associated with the first and second processing delays.

Abstract: A system and method involving a coded modulation scheme whereby different spectral efficiencies can be achieved for different transmitters in a WDM system using the same M2-QAM modulation format. A maximum achievable spectral efficiency for the transmitters may be selected and a spectral efficiency step-size of the maximum achievable spectral efficiency may be specified. The spectral efficiency for any transmitter in the system may be individually selected by reducing its spectral efficiency from the maximum achievable spectral efficiencies by a selected number of steps corresponding to the step size.

Abstract: A method for communicating in a passive optical network (PON), includes receiving traffic from a plurality of optical network units (ONUs) transmitting in an upstream transmission channel, wherein each of the ONUs may transmit at any wavelength within a wavelength band associated with the upstream transmission channel. The method also includes dividing the upstream transmission channel into a plurality of sub-channels, that each include a subset of the wavelength band associated with the upstream transmission channel. The method further includes determining the identity of each of the plurality of ONUs transmitting in each of the sub-channels, assigning a plurality of ONUs transmitting in the upstream transmission channel to each of at least two of the sub-channels based on the determination of the ONUs transmitting in that sub-channel, and allocating transmission timeslots for time-shared transmission by the ONUs in one or more of the sub-channels.

Abstract: When a failure occurs in operational transmission multiplexing transponders 6-1 to 6-N, a wavelength multiplexing optical transmission system carries out selection switching control on N×1 optical switches 5-1 to 5-m and (N+1)×N optical switches 11-1 to 11-m to transmit a wavelength-multiplexed light signal by using reserve transmission and reception multiplexing transponders 6-R and 10-R, thereby sidestepping the failure.

Abstract: An optical transmitter may include an optical source to provide a first optical signal having a varying frequency; an optical circuit to receive a portion of the first optical signal and provide a second optical signal corresponding to a change in frequency of the first optical signal; a photodetector to receive the first optical signal and provide an electrical signal that is indicative of the change in frequency of the first optical signal; an integrator to receive the electrical signal and provide an inverted electrical signal; and a controller to process the inverted electrical signal and provide a current, associated with the inverted electrical signal, to the optical source. The optical source may reduce the phase noise associated with the first optical signal based on the current.

Abstract: A substantially 400 Gb/s optical transceiver includes a substantially 400 Gb/s optical transmitter which includes a set of four substantially 100 Gb/s tunable optical transmitters, each transmitting a substantially 100 Gb/s optical signal in a wavelength division multiplexed form over four channel wavelengths selected such that the resulting 16 channel wavelengths are different from each other and are suitable for WDM, and an optical transmission interface including a set of four 1:4 wavelength division demultiplexers which are operative to demultiplex the substantially 100 Gb/s optical signals to produce substantially 25 Gb/s optical signals over each of the 16 different channel wavelengths, and a 16:1 wavelength division multiplexer which is operative to multiplex the substantially 25 Gb/s optical signals of the 16 different channel wavelengths to generate a substantially 400 Gb/s optical signal.

Abstract: There is provided an optical transmission apparatus including: a transmitter to output an optical signal to be transferred to other optical transmission apparatus; a first dummy light source to generate first dummy light having a wavelength which is not included in an optical signal received from other optical transmission apparatus; a first wavelength-multiplexer to wavelength-multiplex the optical signal received from other optical transmission apparatus, the optical signal output from the transmitter, and an optical signal with a wavelength, of the first dummy light, which is not included in the optical signal received from other optical transmission apparatus and in the optical signal output from the transmitter; and an optical amplifier to amplify an optical signal multiplexed by the first wavelength-multiplexer.

Abstract: Disclosed by way of exemplary embodiments, a 40/50/100 Gb/s Optical Transceivers/transponders which use opto-electronic components at data rates collectively that are lower than or equal to half the data rate, using two optical duobinary carriers. More specifically, the exemplary embodiments of the disclosed optical transceivers/transponders relate to a 43 Gb/s 300pin MSA and a 43˜56 Gb/s CFP MSA module, both include a two-carrier optical transceiver and the appropriate hardware architecture and MSA standard interfaces. The two-carrier optical transceiver is composed of a pair of 10 Gb/s optical transmitters, each using band-limited duobinary modulation at 20˜28 Gb/s. The wavelength channel spacing can be as little as 19˜25 GHz. The same principle is applied to a 100 Gb/s CFP module, which is composed of four tunable 10 Gb/s optical transmitters, with the channel spacing between optical carriers up to a few nanometers.

Abstract: The present invention discloses a multiple star wavelength division multiplexing passive optical network system using a wavelength assignment method. In a multiple star wavelength division multiplexing passive optical network system using a wavelength assignment method according to the present invention, only one WDM-PON system can provide services for a plurality of subscribers who is distributed in a wide range of area through multiple starring, by setting one or more band for transmitting up-stream signals as an up-stream basic band and one or more band for transmitting down-stream signals as a down stream basic band, respectively, and by dividing each of the up-stream basic band and the down stream basic band into a plurality of wavelength sub-bands and assigning the divided sub-bands to different areas using a wavelength division multiplexer/de-multiplexer which splits a band into two or more sub-bands.

Abstract: An optical signal processing apparatus includes: an optical frequency comb generation unit configured to generate an optical frequency comb; an extraction unit configured to extract a plurality of optical components having a certain frequency interval between the optical components from the optical frequency comb; and an optical carrier generation unit configured to multiplex the plurality of optical components with reference light to thereby generate an optical carrier having a center frequency away from the center frequency of the reference light by an integer multiple of the frequency interval.

Abstract: A wavelength-division multiplexing transmission device including: a dummy light source configured to emit and quench dummy light; a monitoring unit configured to monitor an optical level relating to the received wavelength-division multiplexed light; a dummy light controller configured to control the dummy light source to emit dummy light in case where the monitoring unit determines based on the monitored optical level that the wavelength-division multiplexed light is in a condition of input interruption; and a multiplexer configured to multiplex the light of the wavelength modulated based on the transmission data and the dummy light emitted by the dummy light source, wherein the transmitter transmits wavelength-division multiplexed light generated by the multiplexer.

Abstract: A chassis includes a plurality of continuous wave lasers each operable to emit a continuous wave optical beam at the same power as the other lasers, and a plurality of optical couplers operable to input the continuous wave optical beams of the same power and output a plurality of continuous wave optical beams at different powers. The chassis further includes a plurality of optical assemblies operable to modulate the continuous wave optical beams of different powers into a plurality of modulated optical signals at different powers and couple the modulated optical signals onto different length optical mediums so that lower power ones of the modulated optical signals are coupled to shorter ones of the optical mediums and higher power ones of the modulated optical signals are coupled to longer ones of the optical mediums.

Abstract: A laser system includes an array of lasers that emit light at a number of different, fixed wavelengths. A group of optical transport systems connect to the laser system. Each of the optical transport systems is configured to modulate data signals onto the light from the laser system to create optical signals and transmit the optical signals on one or more optical fibers.

Abstract: Techniques, devices and systems for optical communications based on wavelength division multiplexing (WDM) that use tunable multi-wavelength laser transmitter modules.

Abstract: An optical device that includes multiple optical modulators having target operating wavelengths that are distributed over a band of wavelengths and actual operating wavelengths is described. For example, the target operating wavelengths of adjacent optical modulators may be separated by a wavelength increment. Moreover, because of differences between the actual operating wavelengths and the target operating wavelengths of the optical modulators, tuning elements may be used to tune the optical modulators so that the actual operating wavelengths match corresponding carrier wavelengths in a set of optical signals. Furthermore, control logic in the optical device may assign the optical modulators to the corresponding carrier wavelengths based at least on differences between the carrier wavelengths and the actual operating wavelengths, thereby reducing an average tuning energy associated with the tuning elements.

Abstract: A wave division multiplexing (WDM) system is disclosed which accommodates shifts in the resonant frequency of optical modulators by using at least two carriers per optical communications channel and at least two resonant modulator circuits respectively associated with the carriers within each optical modulator. A first resonant modulator circuit resonates with a first carrier and a second resonates with a second carrier when there is a shift in resonance frequency of the at least two resonant optical modulator circuits. A switch circuit controls which carrier is being modulated by its respective resonant modulator circuit.

Abstract: A system and method for sizing transponder pools in a dynamic wavelength division multiplexing optical network having selected nodes designated to have a shared transponder pool is presented.

Abstract: An optical transmission system includes: a plurality of transmitters that output an optical signal having a frequency different from each other; a process unit that adds a reference signal to at least two of the optical signals, the reference signal having a frequency width narrower than that of the two optical signals, an interval of central frequencies of the reference signals being narrower than that of the two optical signals, a multiplexer that multiplexes optical signals output by the plurality of transmitters; an extract unit that extracts a beat signal generated between the reference signals because of a multiplexing of the multiplexer; and an adjust unit that adjusts a frequency interval of the two optical signals in accordance with an extract result of the extract unit.