Abstract: A communications device includes a transmitter device including an optical source configured to generate an optical carrier signal, and a modulator coupled to the optical source and configured to modulate the optical carrier signal with an input signal having a first frequency, an optical waveguide coupled to the transmitter device, and a receiver device coupled to the optical waveguide. The receiver device includes an optical splitter, a first waveguide path coupled to the optical splitter and configured to filter a sideband from the modulated optical carrier signal, a second waveguide path coupled to the optical splitter and configured to generate a selected sideband from selectable sidebands based upon the modulated optical carrier signal, and an optical-to-electrical converter coupled to the first and second waveguide paths and configured to generate an output signal including a replica of the input signal at a second frequency based upon the selected sideband.

Abstract: An insulated bucket truck intercom facilitates safe/reliable bucket-to-cab and bucket-to-ground communications during truck operations, while in close proximity to high voltage power sources/lines. A truck-powered cab transceiver and battery-powered bucket transceiver are interconnected by fiber optic cable to maintain high voltage electrical isolation of at least 10 KV/foot. A hands-free bucket transceiver liberates bucket workers from depressing a PTT button to communicate during repair operations. A PTT cab transceiver prevents stray sounds from distracting bucket workers. Bucket elevation through extension of the telescoping boom, with fiber optic cable secured thereto, is accommodated by a self-storing fiber optic reel assembly on each section. Play in the cable and a spring-loaded pulley member accommodates boom articulation.

Abstract: A method and system of data transmission; the method comprising: converting data into qubits; transmitting a first qubit; measuring the first qubit at receiver location; determining whether or not to transmit portions of data from a sequential successive qubit based upon the value of the first qubit measured at the receiver location.

Abstract: Disclosed is a method for transmitting a low-frequency signal over a data transmission link using a digital high bit-rate signal including the steps of creating a modulated digital high bit-rate signal the average power of which varies according to the low-frequency signal, supplying the modulated digital high bit-rate signal to a first end of the data transmission link, receiving the modulated digital high bit-rate signal at a second end of the data transmission link or at an intermediate node of the data transmission link, and detecting the low-frequency signal by low-pass filtering the received modulated digital high bit-rate signal. According to the invention, the variation of the average power of the modulated digital high bit-rate signal is effected by a variation of the density of “high” bits according to the low-frequency signal.

Abstract: The invention pertains to optical fiber transmission systems, and is particularly relevant to transmission of large volumes of data over long distances at high rates. An improved method and system for transmitting optical data over long distances using filtered return-to-zero (RZ) modulation format is disclosed. In particular, the improvement teaches the proper optical and electrical filtering of the optical signal at the receiver module.

Abstract: An optical transmission apparatus includes an optical transmitter that includes a light emitting element and a driver circuit for the light emitting element, a temperature sensor that detects a temperature of the optical transmitter, and a controller that switches an operation mode of the optical transmitter from a normal mode to a low-power mode so as to reduce a heating effect to the light emitting element and allow an operation of the light emitting element to continue when the temperature detected by the temperature sensor is equal to or higher than a given temperature.

Abstract: A system and method for transporting encrypted data having a transmitter and a receiver is provided. The transmitter generates a sequence of optical pulses, which are copied and output as identical channels. The identical channels are modulated by a plurality of modulators using data to generate a modulated data signal. Respective spectral phase encoders coupled to each of the plurality of data modulators encode respective modulated data signals using a plurality of mutually orthogonal phase codes that are individually associated with the respective spectral phase encoder. These encoded data signals are combined and code-scrambling by a spectral phase scrambler using a scramble code as an encryption key to generate an encrypted signal. A receiver reverses the encryption to extract the data.

Abstract: It is determined that service is to be disconnected for at least a first subscriber of a video content network employing at least one fiber optic cable. The service to the at least first subscriber is provided from a cross-connect cabinet, over the at least one fiber optic cable, to a premises of the at least first subscriber. Sufficient macro-bending loss is induced in the at least one fiber optic cable so as to cause a signal-to-noise ratio at the premises to degrade such that the service is disconnected. The macro-bending loss is induced in a portion of the at least one fiber optic cable which services only the first subscriber. The macro-bending loss can be induced, for example, by winding about a single mandrel, two mandrels in a figure eight pattern, in a tortuous groove in a tray, and so on.

Abstract: A sending/receiving system includes first and second sending/receiving apparatuses. The first sending/receiving apparatus includes a first sending section that sends link establishment information via first transmission channels. The second sending/receiving apparatus includes a second sending section, link establishing sections, and a controller. The second sending section sends link establishment information to the first sending/receiving apparatus via a second transmission channel. Each of the link establishing sections is provided for a corresponding one of the first transmission channels and establishes a link in the corresponding first transmission channel on the basis of the link establishment information.

Abstract: A communication system and method utilizing an infrared signal emitter communicating a predefined signal, and an infrared signal receiver capable of receiving such predefined signal, distinguishing such predefined signal within a field of view of the infrared signal receiver, and providing output indicating the location of the infrared signal emitter within the field of view of the infrared signal receiver.

Abstract: Method for efficiently increasing the capacity of an optical channel which can operate in a given data rate B, by generating N modulated data streams with a bit rate of B/N and a bit-time of N/B at the transmission end, to be simultaneously transmitted from a transmission end to a receiving end of the channel. A shift of 1/B*N between the first modulated data stream and each of its N?1 subsequent modulated data streams is generated using time delay or phase shifting and then the first modulated data stream and its shifted subsequent modulated data streams are combined into a composite multilevel signal with up to N levels and the composite multilevel signal is transmitted to a receiving end of the channel. At the receiving end, the composite multilevel signal is sampled N times during each bit-time, in order to obtain a vector with N elements at each time, such that each element has N+1 possible values and corresponds to the order of a sample.

Abstract: Provided is an optical phase modulating method and apparatus for a quantum key distribution. When an optical phase modulator is arranged outside an optical interferometer, a configuration of the optical interferometer may be simplified, and an extension of an optical path caused by the optical phase modulator, instability and an insertion loss increased in the optical interferometer, and the like, may be overcome. An output feature may be improved by adjusting an applied voltage of the optical phase modulator arranged outside the optical interferometer.

Abstract: The present invention refers to a method for robust multi-level encoding of optical signals. The method uses a transmitter that transforms electric signals into optical signals and a receiver capable to transform optical signals into electric signals. The transmitter is capable to generate optical pulses having at least two different durations. The amplitudes of the pulses are preferably close to each other. The transmitter is fast, and the receiver is slow such that the response time of the receiver exceeds at least the shortest of the durations of the optical pulses. Then the receiver effectively integrates the optical signal and generates the electric signal having a larger amplitude when the optical signal has a larger duration. Thus, the method converts the modulation in pulse duration into the modulation in signal amplitude. In different embodiments of the present invention, the transmitter can be realized by a light-emitting diode, superluminescent light-emitting diode, or a diode laser.

Abstract: An optical communication device includes a transmitter module and a receiver module. The transmitter module includes a two laser sources, two optical modulators optically coupled to the two light sources, respectively, and an optical coupler, a semiconductor optical amplifier, an optical coupler, four optical band-pass filters or a demultiplexer, and an optical multiplexer optically coupled in series. The laser beams emitted from the two laser sources are converted into four laser beams having different frequencies due to a four-wave mixing effect occurring in the semiconductor optical amplifier. The receiver module includes a demultiplexer and four photoelectric conversion elements to receive the four laser beams respectively and convert them to electrical signals.

Abstract: It is provided an optical field transmitter comprising a light source, one or more DA converters, an optical field modulator, a complex information multilevel signal generator circuit, and a phase pre-integration circuit. The optical field modulator modulates light output from the light source into a optical field signal by using the analog signal converted from a complex multilevel information signal including phase pre-integration complex information by the one or more DA converters. A phase angle of the complex multilevel information signal at a complex signal point is any one of values of integral multiples obtained by dividing 360 degrees by a positive integer N. An amplitude value of the complex multilevel information signal at the complex signal point is any one of values of a positive integer M. A total number of the complex signal points which may be taken is lower than a product of N and M.

Abstract: A photoelectric conversion module includes a transmission side photoelectric conversion part for converting an electrical signal into an optical signal, a transmission side circuit board on which the transmission side photoelectric conversion part is mounted off-center to one side of the transmission side circuit board at one end of the transmission side circuit board, a reception side photoelectric conversion part for converting an optical signal into an electrical signal, and a reception side circuit board on which the reception side photoelectric conversion part is mounted off-center to one side of the reception side circuit board at one end of the reception side circuit board. A surface of the transmission side circuit board on which the transmission side photoelectric conversion part is mounted is opposite to a surface of the reception side circuit board on which the reception side photoelectric conversion part is mounted.

Abstract: A method and system for a estimating a most likely location of a periodic SYNC burst within an optical signal received through an optical communications system. A cross-correlation is calculated between a multi-bit digital signal derived from the optical signal and a known symbol sequence of the SYNC burst. The cross-correlation is logically partitioned into sub-blocks. A candidate sub-block in which the SYCN burs is mot likely located is identified, and analysed to estimate a location of the SYNC burst.

Abstract: A light transmission module includes an optical converter for converting an electrical signal to an optical signal; a light transmission path for transmitting the optical signal converted by the optical converter; an electrical transmission path for transmitting an input electrical signal; and a control instructing unit for instructing stop of drive to the optical converter based on a detection of an input electrical signal. When an input electrical signal having a predetermined frequency is detected, the input electrical signal having the predetermined frequency is converted to an optical signal and transmitted in the light transmission path. When input of an electrical signal other than the predetermined frequency is detected, the electrical signal other than the predetermined frequency is transmitted by the electrical transmission path without being converted to an optical signal due to the stop of the drive of the optical converter.

Abstract: According to one embodiment, an optically coupled insulating device includes an optical transmitter and an optical receiver. The optical transmitter includes an analog-to-digital converter, an encoder, a transmitting controller, and an electrooptical transducer. The encoder is configured to generate a transmitting signal by superimposing an output of the analog-to-digital converter onto a signal based on a clock signal. The transmitting signal is encoded to have an average duty ratio of more than zero and less than one. The transmitting controller is configured to output one of the transmitting signal and the output of the analog-to-digital converter depending on an input level of the analog signal. The electrooptical transducer is configured to convert an output of the transmitting controller into an optical signal. The optical receiver includes an optoelectrical transducer, a decoder, and a receiving controller.

Abstract: A system and method for filtering and enhancing signals from a noise background based on the nonlinear interaction of waves. The system and method amplify low-level signals, hide information in the signals, and then nonlinearly recover the signals. With the present invention, this can be performed for both spatial beams and temporal pulses. The signal self-filters and self-amplifies at the expense of the surrounding noise via the nonlinear medium.

Abstract: A phase shift keyed demodulator includes first and second beam splitters, a first optical path, a second optical path, and a wavelength tuner. The first beam splitter splits an input signal into first and second output signals. The second beam splitter splits each first and second output signal into a transmitted signal and a reflected signal. The first optical path includes an optical path of each transmitted signal from a beam splitting surface to a reflector and back to the beam splitting surface. The second optical path includes an optical path of each reflected signal from the beam splitting surface to a mirror surface and back to the beam splitting surface. A path difference introduces a delay between the transmitted signal and the reflected signal. The wavelength tuner tunes the demodulator to a predetermined central wavelength and introduces a phase shift between first and second transmitted signals.

Abstract: Provided herein are various schemes for transmitting out of band (OOB) signals over optical connections that may not support the transmission of such signals. One scheme may involve converting the OOB signals to different types of signals that are supported by the optical connection, while another scheme may utilize a separate parallel connection that supports the transmission of out of band signals in order to extend the optical connection. Yet another scheme modulates the reference clock of the original (in-band) signal to transmit and receive the OOB information.

Abstract: A method and apparatus are present for managing a transmission of photons. The number of parameters for transmitting the photons as a beam in a liquid are identified using a number of characteristics of the liquid to form a number of selected parameters. The photons are transmitted in the liquid as the beam to a target using the number of selected parameters to form the transmission of the photons.

Abstract: A central office optical line terminal (S-OLT) and a local optical line terminal (L-OLT) are connected to through a transmission link form a transmission network. The S-OLT sends service data sent by a service network to the L-OLT through a transmission channel, receives the service data sent by the L-OLT from the transmission channel, and sends the service data to the service network. The L-OLT receives the service data sent by the S-OLT from the transmission channel and sends the service data to an optical network unit (ONU), and sends the service data sent by the ONU to the S-OLT through the transmission channel. Thus, the service data of the L-OLT is sent to the service network through the S-OLT, thereby solving a problem in the existing PON that the service data requires another transmission of the transmission network to reach the service network.

Abstract: A method for remote communication using the interpretation of thermoluminescence or photoluminescence signals uses a property of photoluminescence or of thermoluminescence when it is caused by entangled trapped electrons. In this case, stimulation of deexcitation of trapped electrons by heat or radiation occurs when the deexcitation thermal energy is approximately equal to the trap-emptying energy. Stimulation by a temperature rise of a “master” sample induces luminescence of a remote “slave” “entangled” sample, which is reproduced on lowering the temperature of the “master” sample whatever the distance and the media separating the “master” sample and the “slave” sample. This teaching and its generalization to other forms of stimulation is used by the method of interpreting the quantum reception measurements so as to determine, using a correlation method, the transmission of information or commands.

Abstract: An optical receiver comprising a frame detector configured to receive a polarized signal comprising a first bit stream and a second bit stream, and further configured to identify a plurality of frames in the first bit stream and the second bit stream using a composite header, and a time-domain equalizer (TDEQ) configured to separate the first bit stream and the second bit stream using a portion of the composite header.

Abstract: An optical interface device determines whether frequency deviation of a clock signal corresponding to an optical signal from a client side is abnormal based on a stuff amount when subjecting a data signal corresponding to an optical signal input from the client side to a stuffing process, inserts an alarm indication signal (AIS) indicating that the frequency deviation is abnormal into a predetermined region of a data signal when the deviation is determined to be abnormal, and outputs an optical signal generated corresponding to the data signal to a WDM line side so as to transfer the AIS to another component disposed downstream therefrom, so that locating a site where an abnormal state occurs is made easier.

Abstract: In a communication system in which a station-side line terminal apparatus 1 and a user-side line terminal apparatus 10 perform communication via a plurality of redundant physical lines, the user-side line terminal apparatus 10 monitors an out-of-synchronization error and line abnormality of the physical lines and, when line abnormality is detected (P4), shifts from a registered state to a holdover state for deferring discarding of setting information such as link information. The user-side line terminal apparatus 10 suppresses detection of the out-of-synchronization error during a deferred period to prevent a communication link from being disconnected by the out-of-synchronization error and prevent initial setting from being required. The station-side line terminal apparatus 1 switches a line during the deferred period (P7) and, after transmitting a synchronization signal (P8) to synchronize with the user-side line terminal apparatus, resumes normal communication.

Abstract: A light transmission module has a light transmitting unit having a light emitting portion for outputting an optical signal corresponding to a data signal input as an electrical signal, and a first power supply controller for controlling a drive power supply of the light emitting portion, a light transmission path for transmitting the optical signal introduced from the light transmitting unit, a light receiving unit having a light receiving portion for receiving the optical signal output from the light transmission path and outputting an electrical signal corresponding to the optical signal, and a second power supply controller for controlling a drive power supply of the light receiving portion, and at least one electrical transmission path, connecting the light transmitting unit and the light receiving unit, for transmitting a control signal for controlling power supply to the light emitting portion and the light receiving portion to the first power supply controller and the second power supply controller.

Abstract: A method of transferring data in a projectile launching device includes providing a projectile launching device that has a transmitter and a receiver. An external device also includes its own transmitter and receiver. The receivers are in range with the transmitters. Data is sent from the transmitter on the projectile launching device to the either or both the receiver on the projectile launching device and the receiver on the external device. Data is sent from the transmitter on the projectile launching device to either or both the receiver on the projectile launching device and the receiver on the external device. As a result, the projectile launching device communicates with the external device.

Abstract: A transmitting apparatus includes a plurality of code spreaders different in spreading code, a reception processing unit that selectively distributes transmission data to the plurality of code spreaders, a plurality of optical transmitters each of which that transmit a code-spread signal to an optical fiber as a CDMA optical signal of a carrier wavelength different from that of the other optical transmitters, and a signal multiplexing unit that selectively supplies outputs of the plurality of code spreaders to the plurality of optical transmitters. A receiving apparatus includes an optical receiver that receives a wavelength-division-multiplexed CDMA optical signal from the optical fiber, and a plurality of despreaders connected to the optical receiver and different in spreading code, wherein each of the despreaders reproduces a CDMA signal corresponding to its spreading code from an output signal of the optical receiver.

Abstract: The invention relates to products, methods and devices for remote communication or control using chromogenic materials. Several samples including at least one kind of chromogenic materials are simultaneously irradiated or radiated together by an appropriate entangled radiation, e.g, gamma, X, ultraviolet or visible radiation, provided by a cascade from an atomic source, or by the target of a linear particle accelerator or by a non-linear crystal. When the samples are separated, one of them, qualified as the master, is stimulated by a traditional method that uses infrared or white radiation or by heating, and a signal is measured that represents the partially correlated excess variation of opacity or coloration of the other sample(s), qualified as slave(s). There is no known method of interference between the master and the slaves. The slave(s) are the only ones capable of instantaneously receiving the signal from the master through all media and from any distance.

Abstract: A system for reducing clipping may be used between a multichannel RF source and a laser to reduce or correct clipping that might occur in the laser as a result of negative spikes or peaks in a multichannel RF signal. The system generally includes a clipping correction circuit that receives the multichannel RF signal and responsive to the RF signal, prevents one or more of the negative peaks in the RF signal from causing clipping. The clipping correction circuit may either detect an envelope of the RF signal and/or may detect one or more peaks in the RF signal. One or more negative peaks may be prevented from causing clipping by adjusting a bias current provided by a bias control circuit and/or by modifying the RF signal with one or more clipping correction pulses coinciding with one or more negative peaks.

Abstract: An optical transmission system, where in an optical transmitter a detection bit having a specific pattern set according to the number of bits to be transmitted within one symbol time, is imparted with respect to a transmission signal in which transmission information has been encoded according to a preset format, and an optical signal generated by modulating light according to the transmission signal is transmitted to a transmission line. In an optical receiver, logic inversion or bit swap of received data is detected and compensated by using the detection bit included in the received signal, a decoding process of the compensated received signal is executed. As a result, when an optical signal capable of transmitting multi-bit information within one symbol time is transferred, it is possible to realize excellent transmission characteristics, by reliably compensating an error in received data caused by the modulation format or the multiplex system of the optical signal.

Abstract: The present invention provides methods to mitigate the problems associated with MAC address spoofing and denial of service attacks in an FTTH network system. The MAC address spoofing attack may occur when a computer hacker configures his computer to change the MAC address of a data signal to deceive the receiver of the signal's source address. The denial of service may occur when a computer hacker floods a file server with data packets. The present invention mitigates these attacks by modifying the software of certain components of the FTTH network system to enable the components to insert virtual MAC addresses, tags and codes into the data packets that identify a component of the communication related to the address of the source computer.

Abstract: An optical transmission system for optically transmitting information between apparatuses via an optical transmission path. The system includes: a sending unit that emits, to the optical transmission path, excitation light for detecting an inter-apparatus connection via the path; a responding unit that receives the excitation light from the path and emits detection light to the path using light energy of the excitation light; a response receiving unit that receives the detection light from the path and outputs a detection light current; a detecting unit that detects presence/absence of the inter-apparatus connection based on the detection light current; a light signal transmitting unit that emits, to the path, a light signal for optically transmitting the information based on the detection result by the detecting unit; and a light signal receiving unit that receives the light signal from the path.

Abstract: A method is provided for dispersion compensation of an optical signal communicated in an optical network. The method may include receiving an optical signal comprising a plurality of channels. The method may further include filtering at least one channel from the plurality of channels. The method may also include analyzing the at least one channel of the plurality of channels to measure optical dispersion in the at least one channel. The method may additionally include compensating for optical dispersion based on the measured dispersion.

Abstract: An optical transmission apparatus including a transmitting OTL processor to rearrange a data string stored in a frame into a plurality of logical lanes, and set a lane ID used to identify in which logical lane a beginning of the data string is arranged among the plurality of logical lanes in a non-scramble area in an overhead of the frame, and a receiving OTL processor to respectively identify the lane IDs included in the data string in the respective physical lanes rearranged, determine a generation state of a bit inversion and a lane replacement for each physical lane, compensate the bit inversion and the lane replacement so that the data string in the respective physical lanes becomes same state as the data string in the respective logical lanes, based on the identified result, and rearrange the compensated data string in the respective logical lanes so as to regenerate the frame.

Abstract: Provided herein are various schemes for transmitting out of band (OOB) signals over optical connections that may not support the transmission of such signals. One scheme may involve converting the OOB signals to different types of signals that are supported by the optical connection, while another scheme may utilize a separate parallel connection that supports the transmission of out of band signals in order to extend the optical connection. Yet another scheme modulates the reference clock of the original (in-band) signal to transmit and receive the OOB information.

Abstract: An enhanced 3D integration structure comprises a logic microprocessor chip bonded to a collection of vertically stacked memory slices and an optional set of outer vertical slices comprising optoelectronic devices. Such a device enables both high memory content in close proximity to the logic circuits and a high bandwidth for logic to memory communication. Additionally, the provision of optoelectronic devices in the outer slices of the vertical slice stack enables high bandwidth direct communication between logic processor chips on adjacent enhanced 3D modules mounted next to each other or on adjacent packaging substrates. A method to fabricate such structures comprises using a template assembly which enables wafer format processing of vertical slice stacks.

Abstract: The invention relates to a communications node (10) for routing an optical signal 5 comprising at least one data packet, the node (10) having an input optic fiber (12) and an output optic fiber (14) in communication with each other, the input optic fiber (12) in communication with an optical splitter (20) which is arranged to split an incoming optical signal into at least two substantially identical optical signals, the optical splitter (20) further arranged to pass one of the optical signals to an optical correlator (22) and the other of the optical signals to an input optical switch (24), the optical correlator (22) being arranged to compare an address of the packet with a reference address (40) and to generate a trigger if the reference address (40) matches the address of the packet, the input optical switch (24) being arranged to route the data packet to an optical to electrical converter (28) in response to the trigger.

Abstract: An optical communication system having an optical transmitter and an optical receiver optically coupled via a multi-path fiber. The optical transmitter launches, into the multi-path fiber, an optical transverse-mode-multiplexed (TMM) signal having a plurality of independently modulated components by coupling each independently modulated component into a respective transverse mode of the multi-path fiber. The TMM signal undergoes inter-mode mixing in the multi-path fiber before being received by the optical receiver. The optical receiver processes the received TMM signal to reverse the effects of inter-mode mixing and recover the data carried by each of the independently modulated components.

Abstract: An optical ultrasonic microphone includes an acoustic waveguide that transmits a sound wave received from an opening, an optical acoustic propagation medium that forms at least one portion of a wall face of the acoustic waveguide and an LDV head, and a sound wave proceeding through the acoustic waveguide is received by the optical acoustic propagation medium so that a change in the refractive index caused by the proceeding sound wave inside the optical acoustic propagation medium is generated with high efficiency, and by detecting this as an optical modulation by the LDV head, the optical ultrasonic microphone is allowed to have a very wide band.

Abstract: An optically-connected system is disclosed for exchanging data among industrial automation devices, that is composed of a plurality of connection modules, where each module comprises at least two pairs of optical transmitters and receivers on the main side, and one optical receiver on the opposing main side, that are opposite with respect to another pair of transmitters and receivers in a following module; and where each one of the transmitters and receivers is adapted to communicate with industrial automation devices to cooperate for exchanging data between modules, sending one interrogation signal requesting an identity of the module and the receiver is adapted to send to each corresponding response signal containing characteristics of the receiver.

Abstract: A dual wiring system with easy exchangeability of a function unit. A gate device is mounted in a wall surface of a structure, and connected to both of an electric power line and an information line previously installed in the structure. The function unit has at least one of functions for supplying electric power from the electric power line, outputting information from the information line and inputting information into the information line when connected with the gate device. The function unit has a module connector including an electric power connector and an information signal connector, which is detachably connected to a module port of the gate device comprised of an electric power port and an information signal port. To further improve function expandability, an additional function unit can be detachably connected to the function unit.

Abstract: The invention relates to a device for regenerating the phase of an optically modulated signal with phase changes and based on two and three replicas, wherein the replicas refer to the number of identical signals that are obtained form the input signal. This regenerator is capable of regenerating the phase and period of any format of modulation of optical communications systems which are differential modulation with phase changes, such as: DISK, DQPSK, RZ-DQPSK, RZ-DQPSK, D8PSK, D8PSK, RZ-D16PSK, D16PSK. The regenerator design presented involves the regenerator being placed alter the multiplexer of a communications system and before the signal modulators and/or decoders. Thus the regenerator receives the signal leaving the multiplexer and this signal is input in an amplitude modulator.

Abstract: An optical communication system for generating and transmitting a modulated optical signal in which light emitted by a light source is modulated by an optical modulator in accordance with an input electrical signal. A bias signal generator applies a bias electrical signal to bias the optical modulator at a bias angle away from quadrature. The bias signal generator monitors the input electrical signal and adjusts the applied bias electrical signal in dependence on the input electrical signal. The system further includes a receiver which may include an equalizer coupled to the photodetector of the receiver.

Abstract: The present invention is a radio frequency and digital signal dual carrier multiple modulation system that includes a transmitter system with digital components that include digital inputs, carrier signal sources, a multiplexer and logic controlled radio frequency switches that produces modulated signals and radio frequency components that includes radio frequency signal input and a radio frequency variable gain amplifier. There is also a receiver system with digital components that include a demultiplexer, buffer amplifiers, detectors, comparators and digital signal outputs that receive modulated signals from the transmitter system and radio frequency components with another radio frequency variable gain amplifier that receives the radio frequency output from the transmitter system and produces an amplified radio frequency output.

Abstract: A communication system includes a transmitter that combines and transmits a first signal light and a dummy light having a wavelength different from the first signal light; a first amplifier that amplifies a light transmitted by the transmitter to a constant power; a communication device that separates the dummy light from the light amplified by the first amplifier, has a variable transmittance and allows the separated dummy light to pass through, and combines and transmits the passed dummy light and a second signal light having a wavelength different from the dummy light; a second amplifier that amplifies a light transmitted by the communication device to a constant power; a receiver that receives the second signal light included in the light amplified by the second amplifier; and a controller that controls the transmittance.

Abstract: An optical data bus transceiver (110), optical data bus system (100) and method (300) employ a disambiguation signal to resolve bit ambiguities in a summation signal on an optical data bus (104). The optical data bus transceiver includes a transmitter (112) connected to the optical bus and configured, in conjunction with another transmitter (112?, 120), to produce on the optical bus the summation signal during a first interval and the disambiguation signal during a second interval. The optical data bus transceiver further includes a receiver (114) configured to receive (310) the summation signal. The summation signal includes a summation of separate data signals from each of the transceiver transmitter (112) and the other transmitter (112?, 120). The disambiguation signal includes information to resolve bit ambiguities in the summation signal. A bit ambiguity results from a summation of data bits in each of the respective data signals during a symbol period of the first interval.