| Class / Patent application number | Description | Number of patent applications / Date published |
|---|
| 398184000 | Including polarization | 32 |
| 20080212980 | METHODS AND SYSTEMS FOR POLARIZATION CONTROL AND POLARIZATION MODE DISPERSION COMPENSATION FOR WIDEBAND OPTICAL SIGNALS - An optical processing method includes: receiving an optical signal from an optical system, wherein the optical signal is distorted by frequency-dependent polarization effects in the optical system; spatially dispersing frequency components of the distorted optical signal on a spatial light modulator (SLM); and independently adjusting the polarization transfer matrix of multiple regions of the SLM to reduce the distortion of the optical signal. A related optical processing method includes: providing a precompensation signal indicative of frequency-dependent polarization effects in a downstream optical system; spatially dispersing frequency components of an optical signal on a spatial light modulator (SLM); and independently adjusting the polarization transfer matrix of multiple regions of the SLM to at least partially precompensate the optical signal for distortions caused by the frequency-dependent polarization effects in the downstream optical system. Another related optical processing method includes: providing a model of the frequency-dependent polarization effects; spatially dispersing frequency components of the optical signal on a spatial light modulator (SLM); and independently adjusting the polarization transfer matrix of multiple regions of the SLM based on the model to emulate the optical signal transmission. | 09-04-2008 |
| 20090185810 | SINGLE CHIP TWO-POLARIZATION QUADRATURE SYNTHESIZER, ANALYSER AND OPTICAL COMMUNICATIONS SYSTEM USING THE SAME - An optical beam synthesizer formed on a single chip is provided. It allows M-PSK modulation for both beam polarizations. The synthesizer comprises an optical pulse shaper and two M-PSK modulators for each polarization. A single-chip-integrated analyzer is provided to receive a modulated data. Analyzer comprises a pulse shaper operating as an optical sampler and a pair of 90-degrees optical hybrids for each polarization. Each optical hybrids mix incoming portions of the modulated beams with portions of the local oscillator beams. Both the synthesizer and the analyzer include a set of mirrors located on the back and front surfaces of the chips to create compact designs. The output beams from the analyzer are detected by a set of balanced photodiodes, and the data is recovered. It is another object of the invention to provide a communication system for data transmission having the synthesizer and the analyzer. | 07-23-2009 |
| 20090208225 | VARIABLE OPTICAL ATTENUATOR INTEGRATION INTO TRANSMITTER OPTICAL SUBASSEMBLIES - A small-scale VOA system includes a polarization rotator, a voltage multiplier circuit, and at least one transistor. The polarization rotator can be positioned within a TOSA along the emission axis of a corresponding optical signal source in addition to one or more polarizers. A microcontroller provides a first low voltage control signal to a voltage multiplier to generate a large voltage DC signal which is provided to the transistor. The transistor modulates the large voltage signal with a second control signal from the microcontroller to generate a large voltage AC signal for driving the polarization rotator. The polarization rotation of the polarization rotator can be altered depending on the applied large-voltage AC signal. As a result, the polarization rotator and one or more polarizers can variably attenuate signals emitted by the optical signal source or act as a shutter. | 08-20-2009 |
| 20090257755 | Modulation scheme with increased number of states of polarization - A modulation method for optical communication comprises the step of generating an optical signal modulated between a plurality of different states of polarization and between different phase states. The plurality of states of polarization comprises first states of polarization. The first states of polarization define a single great circle on the Poincaré sphere. The method is characterized in that the plurality of states of polarization further comprise one or more second states of polarization located outside the great circle. Such additional second states of polarization increase the symbol alphabet. | 10-15-2009 |
| 20090310977 | SYSTEMS FOR DEPLOYING AN OPTICAL NETWORK - A transmitter on an integrated circuit chip is disclosed that employs a laser, modulator, and a dispersion compensator module and a modulator for overcoming chromatic dispersion and polarization dependent loss effects. With the present invention, the dispersion compensator module is placed on a chip, either integrated or monolithic, for operation with a laser and a modulator without the need to compensate for dispersion within a separate unit that is not part of the chip. The dispersion compensator module can be implemented, for example, with a ring resonator, an etalon or a Mach-Zehnder interferometer. In a first aspect of the invention, the optical transmitter module of the present invention provides a cost-effective solution for upgrading from an existing optical network to a faster optical network, such as upgrading from a 2.5 Gbps to a 10 Gbps network. In a second aspect of the invention, the optical transmitter module of the present invention provides a means to deploy an optical network at the transmission rate of 10 Gbps, 40 Gbps and faster. | 12-17-2009 |
| 20090317090 | Multichannel Optical Transport Network Skew Control - A system and method are provided for controlling time delay in a multichannel optical transport network transmission device. The method accepts a pair of 2 | 12-24-2009 |
| 20100080571 | OPTICAL SIGNAL TRANSMITTER - An optical signal transmitter includes first and second modulation units, a combiner, and a control unit. The first and second modulation units generate first and second modulated optical signals, respectively. The combiner combines the first and second modulated optical signals to generate a polarization multiplexed optical signal. The control unit controls at least one of the first and second modulation units so that the optical powers of the first and second modulated optical signals become approximately equal to each other. | 04-01-2010 |
| 20100209120 | OPTOELECTRONIC TRANSMISSION SYSTEM AND METHOD - An optoelectronic transmission system has a photoemitter semiconductor component and a photodetector semiconductor component. The photoemitter semiconductor component has a radiation source for converting a first electrical signal into a first electromagnetic radiation and a first polarization filter having a first polarization direction for filtering the first electromagnetic radiation. The photodetector semiconductor component has a second polarization filter having a second polarization direction for filtering a second electromagnetic radiation and a sensor element for converting a second electromagnetic radiation which has been polarized by the polarization filter into a second electrical signal. In this case, the first polarization direction of the first polarization filter is identical to the second polarization direction of the second polarization filter. | 08-19-2010 |
| 20100272446 | CONTROL SYSTEM FOR A POLAR OPTICAL TRANSMITTER - A method of controlling a polar optical transmitter comprising a dual-branch Mach-Zehnder (MZ) modulator driven by a pair of independent electrical drive signals. A cost function is provided which defines a relationship between a control parameter of the optical transmitter and a power level of an output optical signal generated by the MZ modulator. A selected component of the electrical drive signals is dithered using a predetermined dither signal. A modulation depth of the output optical signal power level corresponding to the dither signal is detected, and the control parameter adjusted based on the cost function and the detection result. | 10-28-2010 |
| 20100303469 | CHIP-BASED ADVANCED MODULATION FORMAT TRANSMITTER - In various embodiments, a monolithic integrated transmitter, comprising an on-chip laser source and a modulator structure capable of generating advanced modulation format signals based on amplitude and phase modulation are described. | 12-02-2010 |
| 20110026935 | OPTICAL SIGNAL TRANSMITTER AND METHOD FOR CONTROLLING POLARIZATION MULTIPLEXED OPTICAL SIGNAL - An optical signal transmitter includes: first outer modulator to generate first modulated optical signal, the first outer modulator including a pair of optical paths and a first phase shifter to give phase difference to the pair of optical paths; second outer modulator to generate second modulated optical signal, the second outer modulator including a pair of optical paths and a second phase shifter to give phase difference to the pair of optical paths; combiner to generate polarization multiplexed optical signal by combining the first and second modulated optical signals; phase controller to control the phase difference by the first phase shifter to A−Δφ and control the phase difference by the second phase shifter to A+Δφ; and power controller to control at least one of the first and second outer modulators based on AC component of the polarization multiplexed optical signal. | 02-03-2011 |
| 20110044702 | POLARIZATION MULTIPLEXED OPTICAL TRANSMITTER AND METHOD FOR CONTROLLING POLARIZATION MULTIPLEXED OPTICAL SIGNAL - A polarization multiplexed optical transmitter includes first and second modulation units, combiner, phase controller, and signal controller. The first and second modulation units generate first and second modulated optical signals, respectively. The first and second modulation units include first and second phase shifter to give phase difference between optical paths of corresponding Mach-Zehnder interferometer, respectively. The combiner generates polarization multiplexed optical signal from the first and second modulated optical signals. The phase controller controls the phase difference by the first phase shifter to a target value and the phase difference by the second phase shifter to a value shifted by π from the target value. The signal controller controls operation state of at least one of the first and second modulation units based on optical intensity waveform of the polarization multiplexed optical signal. | 02-24-2011 |
| 20110176815 | MULTI-CHANNEL OPTICAL TRANSCEIVER WITH OFFSET QUADRATURE AMPLITUDE MODULATION - The present disclosure provides a multi-carrier optical transmitter, receiver, transceiver, and associated methods utilizing offset quadrature amplitude modulation thereby achieving significant increases in spectral efficiency, with negligible sensitivity penalties. In an exemplary embodiment, an optical transmitter includes circuitry configured to generate a plurality of optical subcarriers, a plurality of data signals for each of the plurality of subcarriers, and a plurality of modulator circuits for each of the plurality of subcarriers, wherein each of the plurality of modulator circuits includes circuitry configured to offset an in-phase component from a quadrature component of one of the plurality data signals by one-half baud period. | 07-21-2011 |
| 20110176816 | OPTICAL TRANSMISSION APPARATUS - An optical transmission apparatus according to the present invention comprises: a plurality of optical modulating sections serially connected to each other via optical fibers; driving sections corresponding to the optical modulating sections; delay amount varying sections that provide variable delay amounts for modulating signals to be input to the driving sections, to adjust timing between drive signals to be provided for the optical modulating sections; temperature monitoring sections that monitor the temperature of each of the optical fibers and the like; and a delay amount control section that controls the delay amount in each of the delay amount varying sections based on the monitored temperatures. | 07-21-2011 |
| 20110188867 | DQPSK DEMODULATOR - 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. | 08-04-2011 |
| 20110274441 | Methods and Devices for Modulating a Signal - The invention relates to a method in a transmitting node for transmitting a modulated optical carrier signal over an optical channel in an optical communications network to a receiving node. The method enables full use of the polarisation domain within a Poincaré sphere when modulating the optical carrier signal. | 11-10-2011 |
| 20120128374 | APPARATUS AND METHOD FOR PERFORMING COMMUNICATION USING POLARIZED LIGHT - In an apparatus and a method for performing communication by using polarization property of light, a transmission apparatus includes a controller to establish a first channel corresponding to a first polarization property; a signal encoder to encode data into an electrical signal; a light emitting unit to emit light based on the electrical signal; and a polarizer to polarize the light into first polarized light having the first polarization property, and to output the first polarized light. A reception apparatus includes a controller to establish a first channel corresponding to a first polarization property; an analyzer to receive light, and to extract first polarized light having the first polarization property from the light; a polarized light receiver to convert the first polarized light to an electrical signal; and a signal decoder to decode the electrical signal to digital data. | 05-24-2012 |
| 20120148260 | OPTICAL TRANSMITTER AND OPTICAL TRANSMISSION METHOD - An optical transmitter includes: a digital signal processor to generate a drive signal from input data; a controller to control an amplitude or power of the drive signal according to information relating to the digital signal processing of the digital signal processor; and an optical modulator to modulate input light with the drive signal controlled by the controller to generate an optical signal. | 06-14-2012 |
| 20130084079 | GREAT CIRCLE SOLUTION TO POLARIZATION-BASED QUANTUM COMMUNICATION (QC) IN OPTICAL FIBER - Birefringence in optical fibers is compensated by applying polarization modulation at a receiver. Polarization modulation is applied so that a transmitted optical signal has states of polarization (SOPs) that are equally spaced on the Poincaré sphere. Fiber birefringence encountered in propagation between a transmitter and a receiver rotates the great circle on the Poincaré sphere that represents the polarization bases used for modulation. By adjusting received polarizations, polarization components of the received optical signal can be directed to corresponding detectors for decoding, regardless of the magnitude and orientation of the fiber birefringence. A transmitter can be configured to transmit in conjugate polarization bases whose SOPs can be represented as equidistant points on a great circle so that the received SOPs are mapped to equidistant points on a great circle and routed to corresponding detectors. | 04-04-2013 |
| 20130108277 | SIGNAL GENERATING METHOD AND APPARATUS | 05-02-2013 |
| 20130336664 | METHOD AND SYSTEM FOR A LIGHT SOURCE ASSEMBLY SUPPORTING DIRECT COUPLING TO AN INTEGRATED CIRCUIT - Methods and systems for a photonically enabled complementary metal-oxide semiconductor (CMOS) chip are disclosed. The CMOS chip may comprise a laser, a microlens, a turning mirror, and an optical bench, and may generate an optical signal utilizing the laser, focus the optical signal utilizing the microlens, and reflect the optical signal at an angle defined by the turning mirror. The reflected optical signal may be transmitted into the photonically enabled CMOS chip, which may comprise a non-reciprocal polarization rotator, comprising a latching faraday rotator. The CMOS chip may comprise a reciprocal polarization rotator, which may comprise a half-wave plate comprising birefringent materials operably coupled to the optical bench. The turning mirror may be integrated in the optical bench and may reflect the optical signal to transmit through a lid operably coupled to the optical bench. | 12-19-2013 |
| 20140093253 | DUAL-DRIVE MODULATOR - A transmitter module includes a processor configured to receive input data, and determine input values corresponding to the input data; a digital-to-analog converter configured to receive the input values from the processor, and generate first and second voltage signals based on the input values; a laser configured to output light; a Mach-Zehnder modulator configured to receive the light from the laser and the first and second voltage signals from the digital-to-analog converter, and modulate the light based on the first and second voltage signals to generate a modulated optical signal that includes distortion; and a filter configured to receive the modulated optical signal from the modulator, process the modulated optical signal to reduce or eliminate the distortion and produce an output optical signal, and output the output optical signal. | 04-03-2014 |
| 20140133868 | INTENSITY-BASED MODULATOR - An optical modulator includes a splitter, phase modulators, amplitude modulators, intensity modulators, and a combiner. The splitter is configured to receive light, and split the light into portions of the light. Each of the phase modulators is configured to receive a corresponding one of the portions of the light, and modulate a phase of the portion of the light to provide a phase-modulated signal. Each of the amplitude modulators is configured to receive a corresponding one of the phase-modulated signals, and modulate an amplitude of the phase-modulated signal to provide an amplitude-modulated signal. Each of the intensity modulators is configured to receive a corresponding one of the amplitude-modulated signals, and modulate an intensity of the amplitude-modulated signals to provide an intensity-modulated signal. The combiner is configured to receive the intensity-modulated signals, combine the intensity-modulated signals into a combined signal, and output the combined signal. | 05-15-2014 |
| 20140133869 | RZ OPTICAL MODULATOR AND RZ OPTICAL MODULATION METHOD - In an optical transmission system using an RZ code, in order to improve the quality of the modulated transmission signal, an RZ optical modulator includes an RZ carver that outputs a optical pulse train of the RZ code, a polarization adjustment device which improves and outputs a polarization extinction ratio of optical pulse train outputted from the RZ carver and an optical modulator which modulates and outputs the optical pulse train outputted from a polarization adjustment device. | 05-15-2014 |
| 20140233964 | METHOD FOR GENERATING AN OPTIMIZED RETURN-TO-ZERO PULSE SHAPE AGAINST AGGRESSIVE OPTICAL FILTERING AND AN OPTICAL TRANSMITTER IMPLEMENTING THE METHOD - An optical transmitter comprises: first and second sets of optical in-phase and quadrature modulators; an integrable tunable laser assembly; a first polarization beam splitter that is configured to divide the continuous-waveform optical signal into a x-polarized tributary and a y-polarized tributary, each of the x-polarized tributary and the y-polarized tributary is modulated by one of the first and second sets of optical in-phase and quadrature modulators in accordance with the two respective input signals; a second polarization beam splitter that is configured to combine the modulated x-polarized tributary and the modulated y-polarized tributary into one optical signal; and an optical modulator that is configured to modulate the combined optical signal using a driving voltage, wherein the driving voltage has a bias point that is reduced by a predefined offset from a predefined reference voltage level. | 08-21-2014 |
| 20140270807 | SYSTEM AND METHOD FOR SUPPRESSION OF EVEN-ORDER PHOTODIODE DISTORTIONS - A system for suppressing even-order distortion in a photonic link includes a laser for providing laser light to a first input of a Mach-Zehnder modulator (MZM), where the MZM has a second input for receiving an RF input signal, a third input for applying a DC bias voltage to the MZM, and an optical signal output. A dc-voltage-biased photodiode has an input, coupled to the MZM optical signal output, and a modulated RF signal output. The MZM DC bias voltage is set at a value to generate an even-order distortion amplitude substantially equal to an even-order distortion amplitude from the photodiode and 180 degrees out of phase so as to substantially cancel the photodiode even-order distortion. The invention provides the cancellation of photodiode even-order distortion via predisortion linearization with a MZM biased slightly away from quadrature, employing a single fiber run and a single photodiode. The invention provides an improvement in carrier-to-intermodulation ratio (CIR) upwards of 40 dB. | 09-18-2014 |
| 20150071655 | MECHANICAL TRANSLATION OF A VARIABLE RADIATION TRANSMISSION DEVICE - Various embodiments include a variable transmission device including a first smart window panel, a second smart window panel, and a mechanical device configured to linearly translate at least a portion of the first panel relative to the second panel. Further embodiments include a method of varying radiation transmission including the steps of providing a variable transmission device, comprising a first smart window panel, a second smart window panel, and a mechanical device and actuating the mechanical device to linearly translate at least a portion of the first panel relative to the second panel. | 03-12-2015 |
| 20150132013 | ADVANCED OPTICAL MODULATION GENERATION BY COMBINING ORTHOGONAL POLARIZED OPTICAL SIGNALS - Disclosed are adaptive structures and methods for generating advanced modulation formats using multiple levels such as PAM-4, PAM-8 as well as regular OOK or PM OOK formats. Structures and methods disclosed include an unequal power splitter that may exhibit a fixed or tunable splitting ratio such that adaptive format(s) may be generated. | 05-14-2015 |
| 20150341121 | DETECTION AND ALIGNMENT OF XY SKEW - An optical device may include a modulator. The modulator may receive an optical signal. The modulator may modulate the optical signal to include a first channel and a second channel. The modulator may modulate the optical signal based on a training pattern associated with detecting a skew. The modulator may cause the first channel to interfere with the second channel. The modulator may perform a power measurement on the first channel and the second channel. The modulator may determine the skew based on the power measurement and the training pattern. The modulator may time delay the first channel or the second channel to align the skew based on the skew. | 11-26-2015 |
| 20160105238 | ULTRA-WIDE RANGE OPTICAL WAVELENGTH CONVERTER BY DIRECT SIGNAL TRANSLATION FROM INTEGRATED COHERENT RECEIVER TO DUAL-POLARIZATION IQ MODULATOR - A method of wavelength conversion without polarization tracking is provided. A system is also provided that converts an input signal into an output signal of a different wavelength that contains all of the amplitude, phase, and polarization information of the original signal. The method includes separating, using a polarization-diversity optical mixer, an input optical signal of a first wavelength into a plurality of electrical signals containing amplitudes and phases while maintaining the polarization information of the input signal, converting each of the amplitudes and phases into individual photo-currents using a photo-diode, converting each of the output photo-currents into voltages using an amplifier, modulating the multitude of voltages to a second wavelength using a modulator, where the separated electrical signals are up-converted to generate an output optical signal that maintains the same amplitude, phase, and polarization information as was contained in the input signal. | 04-14-2016 |
| 20160105243 | Multinary Signaling based Coded Modulation for Ultra-High-Speed Optical Transport - Systems and methods for communication using an optical transmission system having optical transmitters and receivers includes performing a low-density parity-check (LDPC) encoding; performing nonbinary p | 04-14-2016 |
| 20170237500 | OPTICAL TRANSMITTER AND CONTROL METHOD FOR OPTICAL TRANSMITTER | 08-17-2017 |
