93results about "Optical transmission" patented technology

To reliably monitor an optical transmission line using opposing bidirectional monitor signals.SOLUTION: An optical transmission line monitoring device 50 is one of two opposing optical transmission line monitoring devices connected to each other by an optical transmission line 71 relayed by a relay 70, and includes a transmitter 51 for transmitting an own device monitoring signal 500 to the optical transmission line 71, a receiver 52 for receiving a monitoring signal 520 containing a mixture of a return monitoring signal 700 obtained by returning the own device monitoring signal 500 via the relay 70 and an other device monitoring signal 600 that is transmitted from an opposing optical transmission line monitoring device 60 and differs in pulse width and amplitude from those of the own device monitoring signal 500, a discrimination unit 53 for discriminating the return monitoring signal 700 and the other device monitoring signal 600 included in the monitoring signal 520 by using a discrimination criterion 530 for discriminating the return monitoring signal 700 and the other device monitoring signal 600 from the monitoring signal 520, and an output unit 54 for outputting a discrimination result 540 of the return monitoring signal 700 and the other device monitoring signal 600.SELECTED DRAWING: Figure 7

A receiver of an optical communication system includes an organic photoelectric conversion device configured to convert optical signals received from a transmitter into an electrical signal; and a demodulator configured to input the electrical signal to a trained artificial neural network and demodulate the electrical signal based on an output of the trained artificial neural network.

An optical module, an optical communication device, and an optical communication system, where the optical module may include a control unit, a laser service driving circuit, an optical transmitting unit, and a first optical receiving unit. The control unit determines a target mode of the optical module from a plurality of working modes, and controls the optical module to output a target signal corresponding to the target mode to the laser service driving circuit. The plurality of working modes includes at least one of an OTDR mode and a service mode. The laser service driving circuit outputs a laser signal to the optical transmitting unit based on the target signal. When the target mode is the OTDR mode, the first optical receiving unit receives and transmits, to the control unit, a second OTDR signal returned in an optical fiber.

This application relates to the field of optical communication technologies, and in particular, to an optical module, an optical communication device, and an optical communication system. Costs can be reduced, functions can be added, and an occupied volume can be reduced based on a service function and at least one operation and maintenance function. The optical module may include a control unit, a laser service driving circuit, an optical transmitting unit, and a first optical receiving unit. The control unit determines a target mode of the optical module from a plurality of working modes, and controls to output a target signal corresponding to the target mode to the laser service driving circuit. The plurality of working modes include at least one of an OTDR mode and a service mode. The laser service driving circuit outputs a laser signal to the optical transmitting unit based on the target signal. When the target mode is the OTDR mode, the first optical receiving unit receives and transmits, to the control unit, a second OTDR signal returned in an optical fiber. A first OTDR signal and the second OTDR signal are used to perform optical signal transmission analysis.

An optical network element for a hardware configured optical network includes a first optical port that receives an input optical signal comprising receive control information from the hardware configured optical network. A demodulator optically coupled to the first optical port decodes the receive control information for configuring the optical network element. A modulator having an electrical modulation input that receives transmit control information imparts a modulation onto an optical carrier thereby generating a transmit optical control signal representing the transmit control information. A second optical port transmits the transmit optical control signal representing the transmit control information to the hardware configured optical network.

The optical transmitter (100) includes a modulation signal generation unit (110) that generates a modulation signal, which is a digital signal in which a first pilot symbol signal having a first symbol period and a second pilot symbol signal having a second symbol period are inserted into data to be transmitted, and an optical modulation unit (130) that modulates CW light from a CW light generation unit (140) based on the modulation signal converted into an analog signal by a digital / analog conversion unit (120) to generate modulated light in which the first pilot symbol signal and the second pilot symbol signal are inserted. The optical receiver (200) includes a modulation signal generation unit (110) that generates a modulation signal, which is a digital signal in which a first pilot symbol signal having a first symbol period and a second pilot symbol signal having a second symbol period are inserted into data to be transmitted, and an optical modulation unit (130) that modulates CW light from a CW light generation unit (140) based on the modulation signal converted into an analog signal by a digital / analog conversion unit (120) to generate modulated light in which the first pilot symbol signal and the second pilot symbol signal are inserted. and a receiving-side digital signal processing unit (240) having a frequency difference compensation unit (247) which calculates a phase difference using the first pilot symbol signal and a second pilot symbol signal adjacent to the first pilot symbol signal, which are extracted from the digital signal from the analog / digital converter unit (230) and inserted into the received polarization multiplexed modulated light, and compensates for the frequency of the received digital signal.

An optical transmission system includes a first optical transmission device that transmits an OSC (Optical Supervisory Channel) light to an optical transmission line, and a second optical transmission device that receives for receiving the OSC light from the optical transmission line. The first optical transmission device includes a first controller that detects a transmission line disconnection before communication with the OSC light is established in the optical transmission line, based on a first detection method, and a second optical transmission device including a second controller that detects a transmission line disconnection after the communication with the OSC light is established in the optical transmission line, based on a second detection method different from the first detection method.

A method for reconstructing a first information stream and a second information stream, the method includes receiving, by an optical receiver, a received multiplexed optical signal that is a transmitted optical signal that passed through a polarization and phase rotating medium, the transmitted multiplexed optical signal being generated by using at least one transmitter phase-modulated periodical pilot signal, and by allocating a first polarization to the first information stream and a second polarization that differs from the first polarization to the second information stream; and processing the received multiplexed optical signal to provide a first reconstructed information stream and a second reconstructed information stream, wherein the processing comprises using at least one receiver phase-modulated periodical pilot signal that is associated with the at least one transmitter phase-modulated periodical pilot signal.

This application provides an optical transmitter module, used in the field of optical communication. The optical transmitter module includes a laser, a photoelectric detector, a processor, and a driving circuit. The laser is configured to output a forward optical signal and a backward optical signal based on a driving signal of the driving circuit, where the forward optical signal and the backward optical signal carry a pilot tone modulation signal. The photoelectric detector is configured to convert the backward optical signal into an analog electrical signal. The processor is configured to convert the analog electrical signal into a digital electrical signal. The processor is further configured to obtain a pilot tone modulation depth of the pilot tone modulation signal based on the digital electrical signal, and change the driving signal based on the pilot tone modulation depth. The driving circuit is configured to drive the laser based on a changed driving signal. In this application, the pilot tone modulation depth of the pilot tone modulation signal is adjusted by using the backward optical signal of the laser, so that impact of an operating temperature change or aging of the laser on the pilot tone modulation depth can be reduced, thereby improving communication reliability.

To provide a hardware-configured network.SOLUTION: An optical network element for a hardware-configured optical network comprises a first optical port that receives an input optical signal including reception control information from the hardware-configured optical network. A demodulator optically coupled to the first optical port decodes the reception control information for configuring the optical network element. A modulator having an electrical modulation input that receives transmission control information performs modulation on an optical carrier, thereby generating a transmission optical control signal representing the transmission control information. A second optical port transmits the transmission optical control signal representing the transmission control information to the hardware-configured optical network.SELECTED DRAWING: Figure 8

Adjustment of one of more control parameters of a section (10) of an optical fiber network is accomplished by applying one or more control algorithms using estimated data. The estimated data are derived (4) from measurements (2) of optical signals in the section and from knowledge of the section. The estimated data is a function of optical nonlinearity and of amplified spontaneous emission. Alternately, multiple receivers (64) are comprised in a flexible coherent transceiver (54) of a multi-span optical fiber network, each receiver operative to handle communications on a respective channel. The multiple receivers measure optical characteristics. For each receiver, the optical characteristics include optical nonlinear interactions on the respective channel, the optical nonlinear interactions being at least partially dependent from one span (56) to another span (56). An optical power of a signal on each of the multiple channels is adjusted as a function of the optical characteristics.

Multiple receivers (64) are comprised in a flexible coherent transceiver (54) of a multi-span optical fiber network. Each of the receivers is operative to handle communications on a respective channel. The multiple receivers measure optical characteristics. For each receiver, at least one of the measured optical characteristics is characteristic of optical nonlinear interactions on the respective channel, the optical nonlinear interactions being at least partially dependent from one span (56) to another span (56). An optical power of a signal on each of the multiple channels is adjusted as a function of the optical characteristics.

For an optical monitor device that detects the intensity of light propagating through an optical fiber, a reduction in size and cost of the optical monitor device are to be achieved.The present disclosure provides an optical monitor device including: an optical component that branches an incoming light at a specific branching ratio and outputs the majority thereof in a specific direction and the rest thereof in another specific direction; a plurality of incoming-side optical fibers through which light is to propagate and that are two-dimensionally arranged to cause the light to enter the optical component; a plurality of outgoing-side optical fibers through which light is to propagate and that are arranged to receive the most outgoing light from the optical component; a light-receiving element located to receive a partial outgoing light from the optical component; an incoming-side lens located between the optical component and the incoming-side optical fibers and that causes the incoming light into the optical component to be a parallel light; and an outgoing-side lens located between the optical component and the outgoing-side optical fibers and that efficiently couples the outgoing light from the optical component to the outgoing-side optical fibers.

A slave station device including: a superposition unit that is capable of superposing a main signal and a master station control signal by an electrical domain superposition method in which the main signal and the master station control signal for controlling a master station device connected to the slave station device are converted into an optical signal after multiplexing and an optical domain superposition method in which the main signal is modulated into an optical signal and then optically modulated by the master station control signal, and superposes the main signal and the master station control signal by any one of the electrical domain superposition method and the optical domain superposition method; and a control unit that controls the superposition method by the superposition unit on the basis of a slave station control signal indicating the superposition method received from the master station device.

Described herein is a solution to address the intrinsic nonlinearity of analog signals and the restrictions this places on the signals dynamic range. The subject matter described herein produces linear electro-optic modulation over a dramatically wider range of the input signal amplitude. This is accomplished by a distributed multiwavelength design that “folds” the large dynamic range across multiple linear subranges, with each subrange being addressed using an optical wavelength. As a result, the subrange within the wide dynamic range of the input signal is captured by the linear portion of the transfer function of a single transfer function. Several physical implementations of this subject are presented herein. This innovation enables the efficient use of optical links for the transmission and processing of analog and multilevel signals, overcoming the limitations that were once hindering progress in this field.

An optical transmitter (100) is provided with: a modulation signal generation unit (110) that generates a modulation signal that is a digital signal in which a first pilot symbol signal comprising a first symbol period and a second pilot symbol signal comprising a second symbol period are inserted into the data to be transmitted; and an optical modulation unit (130) that modulates CW light from a CW light generation unit (140) on the basis of the modulation signal converted to an analog signal by a digital / analog conversion unit (120) to generate modulated light into which the first pilot symbol signal and the second pilot symbol signal are inserted. An optical receiver (200) is provided with: a coherent detection unit (210) that receives polarization-multiplexed modulated light into which the first pilot symbol signal comprising the first symbol period and the second pilot symbol signal comprising the second symbol period are inserted, and outputs an analog electrical signal by coherent detection of the received modulated light; and a reception-side digital signal processing unit (240) having a frequency difference compensation unit (247) that calculates a phase difference using the first pilot symbol signal inserted into the received polarization-multiplexed modulated light and the second pilot symbol signal adjacent to the first pilot symbol signal having been extracted from the digital signal from an analog / digital converter unit (230), and compensates for the frequency of the received digital signal.

A transmission apparatus causes a digital-to-analog conversion unit to perform digital-to-analog conversion on transmission signals pre-equalized by using a compensation filter, then converts electrical signals into optical signals, and outputs the optical signals. A receiving apparatus converts the received optical signals into received electrical signals, then performs analog-to-digital conversion, and demodulates the received signals. A scale estimation unit calculates a slope near an amplitude 0 in a correlation between an amplitude distribution of the pre-equalized transmission signals and an amplitude distribution of the received signals. A scale unit scales amplitude of the received signals on the basis of the calculated slope. A coefficient estimation unit calculates a filter coefficient of the compensation filter on the basis of the pre-equalized transmission signals and the scaled received signals. An output amplitude level determination unit determines output levels of the transmission signals from the digital-to-analog conversion unit on the basis of a correlation between distributions of amplitudes of non-pre-equalized and pre-equalized transmission signals.

In some embodiments, an apparatus includes a first optical transceiver. The first optical transceiver includes a set of optical transmitters, an optical multiplexer operatively coupled to the set of optical transmitters, and a variable optical attenuator operatively coupled to the optical multiplexer. The variable optical attenuator is configured to receive a control signal from a controller of the first optical transceiver and modulate a signal representing control information with an output from the optical multiplexer. The control information is associated with the control signal and for a second optical transceiver operatively coupled to the first optical transceiver.

SUMMARY OF THE INVENTION The embodiments of the present application disclose a method and related apparatus for determining a power compensation value of an optical signal that improves the stability of signal transmission. A method in an embodiment of the present application includes the steps of: obtaining a first optical signal and a second optical signal, where the first optical signal is an optical signal obtained by adding or dropping a wavelength to or from the second optical signal; detecting a first optical power of each frequency band in the first optical signal and a second optical power of each frequency band in the second optical signal; calculating, based on the first optical power, a first optical power fluctuation of each frequency band of the first optical signal, which is used after the first optical signal is transmitted from a transmitting end to a receiving end; calculating, based on the second optical power, a second optical power fluctuation of each frequency band of the second optical signal, which is used after the second optical signal is transmitted from the transmitting end to a receiving end; and determining, based on the first optical power fluctuation and the second optical power fluctuation, a first compensation value and a second compensation value, where the first compensation value is used to compensate for the total power of the first optical signal and the second compensation value is used to compensate for the power spectrum tilt of the first optical signal.

An optical transmission system is an optical transmission system for transmitting a signal from an optical transmitter to an optical receiver via at least a transmission line among one or more optical nodes and the transmission line, wherein the optical transmitter includes a digital filter that compensates for, between ripple components that are micro-fluctuating components in a frequency region representing a transmission characteristic of the signal in the optical transmitter and the optical receiver and non-ripple components of the transmission characteristic, at least the ripple components of the transmission characteristic, and at least one of the optical node and the optical transmitter includes an optical filter that compensates for the non-ripple components of the transmission characteristic.

In one embodiment, an apparatus is configured to perform obtaining a received signal from a plurality of Optical Network Units, ONUs connected to the OLT, wherein the received signal includes at least a desired signal originating from a first ONU; determining a magnitude of the desired signal based on the received signal; adjusting an equalizer based on the magnitude of the desired signal; equalizing the received signal using the equalizer such that an equalized signal corresponding to an estimate of desired signal is obtained; and providing the equalized signal for further processing.

The invention is applied to an optical network of the type comprising an optical transmitter [110, Fig. 1], such as an optical line termination (OLT), connected by a first optical fibre to an optical

The embodiment of the application discloses a kind of optical signal sending method, pilot receiver and transmitter, belong to optical communication technical field.The method comprises the following steps: modulating first pilot signal on the first polarization state of optical signal;Modulate the second pilot signal on the second polarization state of optical signal;Wherein, the phase of first pilot signal and the phase of second pilot signal are different;Output modulated optical signal;Using the application, the interference of pilot signal transferred to other wavelength optical signal in the above Raman power transfer effect can be weakened.

An optical transmission device includes a light output unit that outputs OSC (Optical Supervisory Channel) light, a calculator that calculates a tilt amount of a tilt occurring in a pseudo light in an optical transmission line connecting the optical transmission device and another optical transmission device facing the optical transmission device when establishing communication between the optical transmission device and the another optical transmission device based on the OSC light and the pseudo light including a wavelength band of a signal light repeated by the optical transmission device, and a controller that controls output of the pseudo light based on the tilt amount.

An optical transmission system includes a first optical transmission device and a second optical transmission device facing each other via an optical transmission line. The first optical transmission device includes a first optical outputter that outputs first OSC light, a first pseudo light source that outputs first pseudo light including a wavelength band of first signal light, and a first transmitter that transmits first multiplexed light obtained by multiplexing the first OSC light and the first pseudo light toward the second optical transmission device. The second optical transmission device includes a second optical outputter that outputs second OSC light, a second pseudo light source that outputs second pseudo light including a wavelength band of second signal light, and a second transmitter that transmits second multiplexed light obtained by multiplexing the second OSC light and the second pseudo light toward the first optical transmission device.

To provide a method for automatically establishing data connections within a hardware configured network.SOLUTION: A hardware configurable optical element 100 for a hardware configured optical network includes a first optical port that receives an input optical signal containing receive control information from the hardware configured optical network. A demodulator 108 optically coupled to the first optical port decodes the receive control information for configuring an optical network element. A modulator 112 having an electrical modulation input that receives transmit control information imparts a modulation onto an optical carrier thereby generating a transmit optical control signal representing the transmit control information. A second optical port transmits the transmit optical control signal representing the transmit control information to the hardware configured optical network.SELECTED DRAWING: Figure 1A

Multiple receivers (64) are comprised in a flexible coherent transceiver (54) of a multi-span optical fiber network. Each of the receivers is operative to handle communications on a respective channel. The multiple receivers measure optical characteristics. For each receiver, at least one of the measured optical characteristics is characteristic of optical nonlinear interactions on the respective channel, the optical nonlinear interactions being at least partially dependent from one span (56) to another span (56). An optical power of a signal on each of the multiple channels is adjusted as a function of the optical characteristics.

The present application provides a driver amplifier circuit. The driver amplifier circuit includes a nonlinear differential amplifier and a nonlinear resistor connected across the output terminals of the differential amplifier. The nonlinear resistor has a resistance value that increases as the magnitude of the differential voltage across the nonlinear resistor increases. A transmitter may include the driver amplifier.

The present application provides an optical module and parameter transmission method, detection method, control method thereof, and a fronthaul system. The parameter transmission method includes: generating, in response to at least one of a plurality of registers of a far-end optical module becoming a first source register, an uplink optical signal according to ID information and a register value of the first source register, where the first source register is a register having a changed register value of the plurality of registers, and register values of the registers have a mapping relationship with performance parameters of the far-end optical module; and transmitting the uplink optical signal to a near-end optical module of a near-end node.

The optical transmission system (10) of the present invention includes N directly modulated lasers that convert N-channel first electrically modulated signals into N-channel optically modulated signals and transmit them, N photodetectors that receive the N-channel optically modulated signals and convert them into N-channel second electrically modulated output signals, and at least one of a first MIMO equalizer (108) that performs an equalization process on the N-channel first electrically modulated signals to compensate for crosstalk between the N-channel first electrically modulated signals, and a second MIMO equalizer (108) that performs an equalization process on the N-channel second electrically modulated signals to compensate for crosstalk between the N-channel second electrically modulated signals, and uses matrix coefficients based on an impulse response for the equalization process. As a result, the present invention can provide an optical transmission system capable of reducing crosstalk and achieving good BER characteristics.