2762results about "Electromagnetic receivers" patented technology

Accordingly, there are disclosed herein receivers and receiving methods that provide a graceful transition from PAM2 to PAM4 signaling. One illustrative method includes: negotiating a link speed having PAM4 signaling; performing adaption of at least one gain or filter coefficient during PAM2 signaling; switching to PAM4 detection before receiving PAM4 signaling; disabling said adaptation before said switching to PAM4 detection; detecting PAM4 signaling using at least one statistic of detected PAM4 symbols; and enabling said adaptation after PAM4 signaling is detected. Another illustrative method includes: negotiating a link speed having PAM4 signaling; adapting at least one of gain and filter coefficients during PAM2 signaling; monitoring for a change in at least one signal characteristic while performing PAM2 detection; and transitioning to PAM4 detection after detecting said change.

A redundancy link includes a first optical splitter and a second optical splitter. The first optical splitter includes (i) a first hub-side port that optically couples to a first optical line terminal, a first hub-side failover-mode port, (iii) a first plurality of node-side splitter-ports each optically coupled to the first hub-side port and the first hub-side failover-mode port, (iii) a first failover-mode port coupled to the first hub-side port. The second optical splitter includes (i) a second hub-side port that optically couples to a second optical line terminal, a second hub-side failover-mode port optically coupled to the first failover-mode port, (iii) a second plurality of node-side splitter-ports each optically coupled to the second hub-side port and the second hub-side failover-mode port, (iii) a second failover-mode port coupled to the second hub-side port.

The invention relates to the technical field of satellite laser communication, and discloses a laser communication double-end on-orbit calibration system and method, and the system comprises an A end and a B end which are in communication connection and have the same structure; the end B is a second laser communication terminal; the A end is a first laser communication terminal which comprises a main light path, and a transmitting branch, a receiving branch, a tracking branch and a calibration branch which are connected with the main light path; the main light path is composed of an A-end optical antenna, an A-end reflex reflector, an A-end fine tracking galvanometer, an A-end first spectroscope, an A-end second spectroscope, an A-end third spectroscope and an A-end emission galvanometer which are connected in sequence; the transmitting branch is connected with the A-end transmitting galvanometer; the receiving branch is connected with the A-end third spectroscope; the calibration branch is connected with the A-end second spectroscope; and the tracking branch is connected with the A-end first spectroscope. According to the invention, on-orbit receiving and transmitting coaxial calibration is carried out, calibration is carried out without the help of a ground end, and the efficiency is improved.

An optical ranging system includes a coherent IQ receiver configured to receive a radio frequency (RF)-encoded optical signal, generate an in-phase (I) electrical signal and a quadrature (Q) electrical signal based on the RF-encoded optical signal; a first analog-to-digital converter (ADC) configured to convert the I electrical signal into an I digital signal; a second ADC configured to convert the Q electrical signal into a Q digital; and a processing circuit configured to generate a power signal having the target frequency by squaring the I digital signal and the Q digital signal, and summing a squared I digital signal and a squared Q digital signal. The processing circuit is configured to analyze the power signal to determine a signal phase corresponding to signal peaks associated with the target frequency, and determine a distance value based on a phase difference between the signal phase and a reference power signal.

The invention discloses a laser channel atmospheric turbulence fading real-time compensation device and method based on a galvanometer system, and the method comprises the steps: enabling an incident light beam to irradiate a transparent PCB integrated with a photodiode array after the incident light beam is focused through a convex lens, obtaining the light intensity distribution of a current light spot through the photodiode array, and transmitting the light intensity distribution to a signal processing unit; the signal processing unit coarsely adjusts the deviation direction of the light spots according to the received light intensity distribution data, and aligns the part with the strongest light intensity in the light spots to the end face of the optical fiber; and based on the roughly adjusted light spot deviation direction, the signal processing unit dynamically adjusts the deflection angle of the galvanometer by using a gradient descent method according to the power measurement value of the receiving coupling module, so that the fine adjustment of the light spot deviation direction is realized, and the receiving coupling power is maximized. The objective of receiving optical power maximization is achieved, optical design, electronic control and algorithm optimization are combined, and atmospheric turbulence compensation with high cost performance is achieved.

The invention discloses a wireless optical communication alignment system and a capture alignment method thereof, and relates to the technical field of optical communication, and the method comprises the steps: a three-dimensional holder carries out the coarse alignment of an optical path between a transmitting end and a receiving end according to the direction of beacon light; an alignment device located at the top of the three-dimensional holder carries out fine alignment on the light path; the alignment device comprises a two-dimensional alignment structure, a control circuit and a device shell. The control circuit captures a light intensity feedback value of the light intensity sensor of the two-dimensional alignment structure, and adjusts an azimuth angle and a pitch angle of the optical fiber collimator of the two-dimensional alignment structure according to the light intensity feedback value so as to adjust lens orientations of the transmitting end and the receiving end; the device shell provides a supporting platform for the two-dimensional alignment structure and the control circuit and is connected with the three-dimensional holder. Coarse alignment and fine alignment are combined, accurate angle adjustment is achieved through light intensity feedback, efficient alignment of light paths of the transmitting end and the receiving end is ensured, meanwhile, the device shell provides stable support and connection, and the stability and reliability of the alignment process are guaranteed.

The invention discloses an adaptive equalization method for combined compensation of carrier frequency offset and channel linear damage. The adaptive equalization method specifically comprises the following steps: taking data subjected to matched filtering, clock synchronization, orthogonality and normalization as input signals; for an input signal, using the filter linear damage compensation weight vector and the frequency offset compensation weight coefficient to obtain output data of the filter; obtaining an expected value of filter output data, and calculating to obtain a theoretical error value of adaptive equalization; and obtaining a filter weight vector used for next adaptive equalization according to the theoretical error value. The adaptive equalization method for combined compensation of carrier frequency offset and channel linear impairment is suitable for a coherent optical transmission system, uses an adaptive equalizer to compensate signal frequency offset and channel linear impairment at the same time, does not need an additional frequency offset estimation algorithm, meets the advantages of multiple rates and multiple modulation formats, and is high in convergence speed and high in robustness. And the calculation complexity is low.

A method is disclosed for use in detecting a pulsed optical beam when the pulsed optical beam is transmitted through a scattering medium, wherein the pulsed optical beam comprises a plurality of optical pulses and the method comprises using a plurality of photodetectors of a photodetector array to detect light which is scattered progressively from the same optical pulse as the optical pulse propagates through a plurality of regions of the scattering medium and which is then received progressively on different photodetectors of the photodetector array. The method may be used in particular, though not exclusively, for non-line-of-sight free-space optical communications. An optical receiver for use in detecting the pulsed optical beam and an associated optical system are also disclosed.

The invention discloses a method of an optical anti-turbulence device for polarization multiplexing spatial optical communication. The mode demultiplexer is connected with the optical fiber; the single-mode optical fiber array is respectively coupled with each spatial intrinsic mode decomposed by the mode demultiplexer; the polarization CBC chip is connected with the other end of the single-mode optical fiber array; the driving control module is connected with the polarization CBC chip; the polarization multiplexing optical communication digital coherent receiver (Rx) is connected with the polarization CBC chip through a single-mode optical fiber; through the arrangement of the polarization CBC chip, the compatibility of a polarization multiplexing technology and a mode multiplexing coherent beam combination technology is realized, the problem of polarization dimension information loss or strong crosstalk caused by the use of a polarization state rotator (PSR) and a polarization maintaining optical fiber in the prior art is solved, modulation information of two orthogonal polarization dimensions is completely reserved, the communication bandwidth is improved, and the communication efficiency is improved. And the communication efficiency is greatly improved.

An adjustable bandwidth current-to-voltage converter for use in an optical receiver includes an input configured to receive current from a photodetector; an amplifier stage connected to the input; a feedback path connected to the amplifier stage and to an output, wherein the feedback path includes a feedback element and an operating mode switch configured to set one of photodetector amplifier with dynamic load (PADL) mode and an integrate-and-dump (I&D) mode. The PADL mode is for higher baud operation than the I&D mode.

Aspects of the subject disclosure may include, for example, receiving a plurality of modulated optical wavelengths generated from digital input data and unmodulated optical wavelengths. The one or more of the plurality of modulated optical wavelengths undergo an optical operation and are converted into one or more electrical signals. The optical operation increases a signal to noise ratio (SNR) of the one or more electrical signals to exceed an SNR threshold. Additionally, the one or more electrical signals are processed to produce digital output data. Other embodiments are disclosed.

Chromatic dispersion compensation is performed in one or more pluggable optical transceiver (POT) devices operating within an intensity-modulated direct-detection (IMDD) optical network. Compensation is performed within each POT using an electrical and / or optical chromatic dispersion module which are controlled by a set of parameters. A network computing device includes a computer processor and a host management interface for communicating with the POT. In the event of a link failure, the computer processor determines a second set of parameters to control the one or more dispersion compensation module(s) of the POT. The second set of parameters are different from a first set of parameters used to control the one or more compensation module(s) in the case of a first optical path. The computer processor causes the POT to use the second set of parameters in place of the first set of parameters.

This disclosure relates to a receiver device for pulse amplitude modulation (PAM) signals. The receiver device calculates a transmitter dispersion eye closure quaternary (TDECQ). The receiver device first obtains a signal, wherein the signal is based on a PAM signal sent by a transmitter device over a channel to the receiver device, and filters the obtained signal. Further, the transmitter device equalizes the filtered signal using a FFE with multiple taps, and filters the equalized signal output by the FFE using a 2-tap post filter, wherein high frequency noise caused by the FFE is compressed. The receiver device applies a Max-Log-Map (MLM) algorithm on the filtered signal output by the 2-tap post filter, reconstructs a signal constellation of the PAM signal based on the result of the MLM algorithm, and calculates a TDECQ based on the reconstructed signal constellation.

The invention belongs to the technical field of signal processing, and particularly relates to a coherent light high-speed transmission signal processing method based on deep joint compensation, which comprises the following steps of: performing fine frequency offset and inter-carrier interference joint preprocessing on a coherent light receiving sampling sequence; obtaining a pre-processing output sequence and at least one estimation parameter derived from fine frequency offset and inter-carrier interference combined pre-processing; inputting the preprocessing output sequence into a diffusion type score guide joint compensation network module to obtain a deep joint compensation sequence; performing online judgment and decoding on the deep joint compensation sequence, and adaptively updating internal parameters of the diffusion type score guide joint compensation network module when a preset adaptive updating condition is met; according to the invention, the symbol residual error can be obviously reduced, the forward error correction gain can be improved, and the stability and robustness of the system under high-order modulation, high symbol rate and long-distance link scenes can be enhanced.

The invention provides a communication device and a communication method, relates to the field of communication, and is beneficial for reducing impact on the performance of the communication device due to different atmospheric turbulence intensities and maintaining the stability of the performance of the communication device. The communication device comprises an optical receiving module, a first optical transmission module, a second optical transmission module and a control module, the optical receiving module is used for receiving optical signals, the first optical transmission module is used for performing multimode transmission on the optical signals from the optical receiving module, and the second optical transmission module is used for performing single-mode transmission on the optical signals from the optical receiving module; the control module is used for controlling the optical signals from the optical receiving module to be input into the first optical transmission module under the condition that target parameters conform to a first condition, or controlling the optical signals from the optical receiving module to be input into the second optical transmission module under the condition that the target parameters conform to a second condition, and the target parameters comprise parameters related to atmospheric turbulence; the intensity of the atmospheric turbulence in the first condition is greater than that in the second condition.

The invention belongs to the technical field of coherent optical communication, and particularly relates to a real-time frequency offset compensation method for a coherent optical communication system. Comprising the following steps: generating residual optical carriers at a transmitting end by adjusting bias voltage of an IQ modulator; receiving a signal at a receiving end, processing the received signal to obtain a frequency offset between an information source and the local oscillator laser, feeding back the frequency offset, adjusting the output frequency of the local oscillator laser to carry out frequency offset compensation, and carrying out continuous iteration to realize frequency locking of the laser; when a received signal is processed, the signal is sampled through an ADC (Analog to Digital Converter) with a low sampling rate, an FFT (Fast Fourier Transform) is combined with a Chirp-z algorithm to obtain a fine frequency offset value, then the frequency offset value is converted into a controlled variable by a PID (Proportion Integration Differentiation) algorithm, and the controlled variable is converted into an analog voltage through a DAC (Digital to Analog Converter), so that the frequency of a local oscillator laser is adjusted; the method is low in complexity, is suitable for all coherent optical communication systems, lays a foundation for the coherent optical communication system with the single baud rate, and can effectively reduce the communication cost and power consumption.

The invention provides a light beam demodulation detector based on a multi-layer metasurface and a construction method of the light beam demodulation detector based on the multi-layer metasurface, and the light beam demodulation detector comprises an image processing chip and the multi-layer metasurface. The structured light beam to be identified generates a plurality of diffraction beams after passing through the diffraction neural network formed by the multi-layer metasurface; the diffracted light beams generate different light intensity distributions on the upper surface of the image processing chip, so that the image processing chip determines the type of the structured light beams to be recognized based on the light intensity distributions, and demodulation recognition of the light beams is achieved. According to the light beam demodulation detector based on the multi-layer metasurface and the construction method of the light beam demodulation detector, a demodulation component is constructed by utilizing diffraction neural network simulation and the multi-layer metasurface so as to realize demodulation transmission of structured light beams, and recognition of the types of the light beams is realized in combination with an image processing chip; and a compact light beam demodulation detection device with a miniaturized structure is optimally designed.

The invention relates to the technical field of optical wireless communication, in particular to an optical wireless communication device and method based on beam shaping, and the device comprises a beam shaping module which comprises at least one beam shaping lens so as to convert a beam outputted by a point light source into a uniformly distributed linear or planar light field; the optical transceiver module comprises a plurality of optical base stations, the optical base stations are arranged in a redundant mode in the extension direction of the communication scene, each optical base station integrates at least one optical transmitter, an optical detector and a plurality of prisms and is used for transmitting and receiving optical signals, and the coverage range of the single optical base station is expanded through the prisms; and the dynamic demodulation module is connected with the optical detector, and dynamically adjusts the demodulation threshold value of the corresponding bit error rate according to the real-time channel state. Therefore, when the technology is applied to wireless optical communication, the communication performance can be improved, the coverage distance can be increased, the coverage uniformity can be improved, the bit error rate can be reduced, the construction cost can be reduced, and the long-term stable communication requirement of a closed scene can be met.

Consistent with the present disclosure, an encoder circuit is provided at a transmit side of an optical fiber link that maps an input sequence of bits of fixed length k a sequence of symbols of a codeword of length n, such that the symbols of the codeword define a predetermined transmission probability distribution. Preferably, each symbol of the codeword is generated during a corresponding clock cycle, such that after n clock cycles, a complete codeword corresponding to the input bit sequence is output. On a receive end of the link, a decoder is provided that outputs the k-bit sequence every n clock cycles. Accordingly, buffers need not be provided at the output of the encoder and the input of the decoder, such that processing of the input sequence, codewords, and output sequence may be achieved efficiently without large buffers and complicated circuitry. Moreover, the input sequence, with any binary alphabet may be matched to a desired output distribution with any arbitrary alphabet. Accordingly, probabilistic constellation shaping may be achieved over constellations of arbitrary size. In addition, relatively long codewords, may be encoded and decoded with the apparatus and method disclosed herein. Accordingly, for a fixed SNR a higher SE (more bits per symbol) can be achieved. Alternatively, for a fixed SE, a lower SNR may be sufficient. Moreover, the resulting SE may be finely tailored to a particular optical link SNR to provide data transmission rates that are higher than the low order modulation formats that would otherwise be employed for optical signals carried by such links.

The invention discloses a photodiode receiving assembly with a light splitting function and application thereof. The photodiode receiving assembly comprises a light splitting prism, a first light condensing element, a second light condensing element, a first photodiode chip and a second photodiode chip, the beam splitter prism is provided with an incident surface, an emergent surface, a beam splitting surface and a reflecting surface, the light splitting surface is configured to respectively transmit and reflect two optical signals with different wavelengths in the dual-wavelength mixed optical signals; the reflecting surface is configured to be used for changing the transmission direction of a reflected light signal, so that the reflected light signal and a transmission light signal transmitted from the light splitting surface are parallel to each other and are transmitted to the emergent surface in a spaced manner to be output; the output transmission light signal sequentially passes through the first light condensing element and the first photodiode chip; and the output reflected light signal sequentially passes through the second light condensing element and the second photodiode chip. The receiving assembly integrates the light splitting, converging and receiving functions of optical signals, miniaturization can be achieved, and the TO packaging requirement is met.

The invention relates to the technical field of digital demodulation, in particular to a digital demodulation method suitable for deep ultraviolet light communication, which comprises the following steps of: adopting multiple delay processing with half code element width, and respectively carrying out double extraction processing on a discrete sampling signal which is not subjected to delay processing and a plurality of delay sampling signals to obtain a plurality of delay extraction signals; in this way, the key sampling time in the coverage code element period can be ensured, and a basis is provided for subsequent accurate synchronization; a plurality of delay extraction signals are respectively input into corresponding equalization processing units, a preset local training sequence is loaded to each equalization processing unit to obtain a plurality of equalization filtering signals, and the plurality of equalization filtering signals and the preset local training sequence are respectively subjected to related judgment processing, so that the inter-symbol interference is inhibited, and meanwhile, the equalization processing efficiency is improved. The synchronization signal can be quickly screened out, so that the problem that inter-symbol interference and synchronization are difficult to consider in a traditional demodulation method is solved, and the demodulation efficiency and reliability are remarkably improved.

The invention discloses an LPO wired receiver adopting adaptive CTLE based on a genetic algorithm, and the receiver comprises an analog front end, a data sampler, an edge sampler, an error sampler, a 1: 32 demultiplexer, a verification module, an eye pattern monitor, a genetic algorithm module, clock recovery logic, and a clock path. The eye pattern monitor is used for calculating the eye pattern closure degree according to the data of the data sampler and the error of the error sampler and outputting the eye pattern closure degree to the genetic algorithm module; and the genetic algorithm module is used for realizing parameter adaptive control of a continuous time linear equalizer CTLE and a variable gain amplifier VGA in the analog front end. The invention aims to apply the genetic algorithm to the adaptive equalization of the adaptive continuous time linear equalizer, so that the adaptive continuous time linear equalizer has stronger global search capability and lower power consumption and is not easy to fall into local optimum, and the complexity and power consumption of the adaptive continuous time linear equalizer are reduced. And the real-time and energy-saving requirements are met.

The invention provides a frequency offset estimation method and device for a digital subcarrier coherent optical communication system, and relates to the technical field of communication. According to the method, when frequency offset estimation is carried out on a received digital subcarrier signal, empirical mode decomposition is carried out on the signal, namely, an eigenmode function derived by a noisy signal is used for carrying out frequency offset estimation on the signal; decomposing the signal into a plurality of eigenmode components and residual components; using different numbers of eigenmode components to reconstruct a plurality of signals with the residual components; through quartile outlier detection and clustering analysis, a reconstruction signal which most meets the requirement is selected in a self-adaptive mode to serve as a final reconstruction result; and finding out the frequency position of a specified point from the reconstructed signal to carry out frequency offset estimation. According to the method, blind frequency offset estimation in a PDM-16 / 64QAM DSCM system can be accurately and stably realized within a certain error allowable range, and the method has the advantages of being small in error, applicable to different roll-off factors, capable of processing large frequency offset and the like.

A first portion of incoming light and a second portion of incoming light travel in opposite directions within a first optical waveguide. A ring resonator in-couples the first portion of incoming light and the second portion of incoming light from the first optical waveguide, such that the first portion of incoming light and the second portion of incoming light travel in opposite directions within the ring resonator. A second optical waveguide is disposed to in-couple the first portion of incoming light and the second portion of incoming light couple from the ring resonator, such that the first portion of incoming light and the second portion of incoming light travel in opposite directions within the second optical waveguide away from the ring resonator. One or more photodetector(s) are optically connected to receive the first portion of incoming light and the second portion of incoming light from the second optical waveguide.

The invention provides an OIO core particle and an AI computing cluster, which are applied to the technical field of photoelectric transmission, and the OIO core particle comprises an optical chip, an electric chip and a micro-control chip or a micro-control application-specific integrated circuit. An optical chip, an electric chip and a control unit are packaged into an OIO core particle, the core particle works independently as an OIO, and the bandwidth and linearity of a system are improved by adopting an analog light and electric equalization technology in the optical chip and the electric chip. And the core particles are applied to a Scale-up network in the node and are used for interconnection between GPUs (Graphics Processing Unit). Compared with a copper cable interconnection scheme, the method has the advantages that the interconnection distance can be greatly increased, and the scale of a Scale-up network for GPU interconnection is expanded; compared with the existing optical module interconnection scheme, the optical module interconnection method has the advantages of low time delay, low power consumption, high bandwidth density and high reliability; the chip particle interconnection can adapt to the diversity requirements of AI chips and systems, and can be integrated into their systems by clients according to their own requirements.

The invention provides a fault signal detection system and an analysis positioning method, and relates to the technical field of signal detection. An injection module is used for periodically applying narrowband acoustic disturbance capable of adaptively selecting frequency and power to an optical cable sheath; the passive wireless label nodes arranged along the line collect multi-dimensional data such as arrival timestamps, amplitudes, frequencies, phases, local temperatures and the like in real time, and upload the data through near-field coupling. And the convergence module completes node identification association and batch aggregation, the analysis and construction module constructs an acoustic propagation path map, and after temperature difference segmentation compensation, an actual laying path is dynamically recovered by adopting a map search algorithm. And the projection and identification module maps the map to a geographic information system coordinate system and outputs a fault space position, thereby realizing real-time and accurate optical cable fault positioning under a topology-free prior condition, remarkably reducing manual inspection and misjudgment rates, and being suitable for a multi-branch and multi-repair long-distance communication or power optical cable scene.

The invention relates to the technical field of optical communication, and discloses a multi-dimensional and multi-phase-based 50G PON signal noise compensation method, which comprises the following steps: S1, generating a mixed signal, including superposing a multi-phase orthogonal pilot signal into a data signal time domain at a transmitting end according to a preset proportion lower than the power of a data signal; and S2, transmitting the mixed signal in a polarization multiplexing mode, wherein the polarization multiplexing adopts double-channel parallel transmission of an X polarization state and a Y polarization state. Multi-phase orthogonal pilot signals are superposed to a data signal time domain in a low-power proportion at a transmitting end, polarization multiplexing dual-channel transmission is adopted, a narrow-band filter is utilized at a receiving end to separate pilots and calculate channel damage parameters, and a finite impulse response filter is configured to perform linear equalization compensation. And the simplified Kalman filtering algorithm is combined to estimate the phase noise and correct the phase, so that collaborative suppression of the linear channel damage and the phase noise in the 50G PON signal is facilitated.

A method for topological design optimization in which a number of objective scattering(S) parameters are initially decomposed into a product of smaller devices (primitives). Each of the primitives are optimized in parallel using inverse design; and the topologies of the smaller devices are then composited into a final device design region, in which the final device design region is an initialization of a final optimization, advantageously saving computation time. According to at least one embodiment, the herein described optimization procedure can be utilized in order to design a composite power combiner that is essentially phase-insensitive.

The invention discloses an optical interconnection system which comprises a light source, a transmission medium and a photoelectric detector. The light source adopts a micro resonant cavity light-emitting diode array, and the transmission medium adopts a multi-core plastic optical fiber. An optical signal output by the micro resonant cavity light emitting diode array is transmitted to the photoelectric detector through the multi-core plastic optical fiber and is converted into an electric signal through the photoelectric detector. The light source of the optical interconnection system provided by the embodiment of the invention adopts the micro resonant cavity light-emitting diode array, the transmission medium adopts the multi-core plastic optical fiber, and good balance among low power consumption, high stability and high parallelism can be achieved through component optimization.

The invention discloses a light-weight wide-angle atmosphere laser communication device, system and method based on reverse modulation inertial navigation cooperation, and solves the technical problem that an existing atmosphere laser communication system is large in size and weight. The atmosphere laser communication system comprises at least one active communication device and at least one passive communication device, wherein the active communication device comprises a first main control unit, an optical signal generation modulation unit, a direction adjustment unit, a first optical receiving unit, a first optical signal acquisition unit, a first electric signal processing unit and an aiming unit; the pointing adjustment unit comprises an inertial navigation measurement module and a first MEMS fast reflecting mirror; the passive communication device comprises a second optical receiving unit, a second optical signal acquisition unit, a second electric signal processing unit, a second main control unit and an MRR modulation unit. According to the invention, a scheme of cooperation of light beam pointing compensation and reverse modulation of inertial navigation measurement is adopted, and the problem that the communication field angle, volume and weight of an atmospheric laser communication system are mutually restricted is solved.