WO2023061213A1 - Procédé et appareil d'extraction d'obliquité de signal optique, dispositif électronique et support de stockage - Google Patents

Procédé et appareil d'extraction d'obliquité de signal optique, dispositif électronique et support de stockage Download PDF

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WO2023061213A1
WO2023061213A1 PCT/CN2022/121778 CN2022121778W WO2023061213A1 WO 2023061213 A1 WO2023061213 A1 WO 2023061213A1 CN 2022121778 W CN2022121778 W CN 2022121778W WO 2023061213 A1 WO2023061213 A1 WO 2023061213A1
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channel
compensation
adaptive
way
optical signal
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PCT/CN2022/121778
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English (en)
Chinese (zh)
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梁俊鹏
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中兴通讯股份有限公司
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
    • H04B10/07—Arrangements for monitoring or testing transmission systems; Arrangements for fault measurement of transmission systems
    • H04B10/075—Arrangements for monitoring or testing transmission systems; Arrangements for fault measurement of transmission systems using an in-service signal
    • H04B10/079—Arrangements for monitoring or testing transmission systems; Arrangements for fault measurement of transmission systems using an in-service signal using measurements of the data signal

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  • the embodiments of the present application relate to the field of optical communications, and in particular, to a method, device, electronic device, and storage medium for extracting optical signal damage.
  • the front end of a coherent transceiver usually suffers from amplitude imbalance, phase imbalance, and IQ (in-phase component and quadrature component) impairments (skew), etc.
  • the amplitude imbalance and phase imbalance can be compensated and monitored by the Gram-Schmidt Orthogonalization Procedure (Gram-Schmidt Orthogonalization Procedure, referred to as "GSOP").
  • Gram-Schmidt Orthogonalization Procedure referred to as "GSOP"
  • GSOP Gram-Schmidt Orthogonalization Procedure
  • interpolation is mainly used to compensate, but due to temperature changes, device aging and other reasons, the value of IQ skew changes slowly, and the static interpolation filter cannot adaptively compensate for IQ skew.
  • some equalization methods for adaptively compensating for skew have emerged, including using a generalized linear equalizer for adaptively compensating for skew.
  • the main purpose of the embodiments of the present application is to provide a method, device, electronic device and storage medium for extracting optical signal impairments, so as to realize adaptive compensation for skew and extract skew values.
  • the embodiment of the present application provides a method for extracting optical signal damage, including the following steps: obtaining the sampling data of the I channel and the Q channel after the received light is mixed; Compensation at the receiving end; wherein, the adaptive compensation includes adaptive receiving end compensation, and/or adaptive transmitting end compensation; obtaining the converged receiving equalization tap coefficients obtained by the adaptive receiving end compensation; obtaining according to each receiving equalizing tap coefficient Impairments at the receiving end of the I-path and the Q-path; where the impairments include impairments at the receiving end corresponding to adaptive compensation, and/or impairments at the transmitting end.
  • the embodiment of the present application also provides an optical signal damage extraction device, including: an analog-to-digital converter, used to obtain the sampling data of the I channel and the Q channel after the received light is mixed; a generalized linear equalizer, used Adaptive compensation is performed on the sampling data of the I channel and the Q channel; wherein, the adaptive compensation includes adaptive receiver compensation, and/or, adaptive transmitter compensation; the damage extraction module is used to obtain the convergence obtained by the adaptive compensation After each equalization tap coefficient, the impairments of the I path and the Q path are obtained according to each equalization tap coefficient; wherein, the impairment includes an impairment at the receiving end corresponding to the adaptive compensation, and/or an impairment at the transmitting end.
  • an analog-to-digital converter used to obtain the sampling data of the I channel and the Q channel after the received light is mixed
  • a generalized linear equalizer used Adaptive compensation is performed on the sampling data of the I channel and the Q channel
  • the adaptive compensation includes adaptive receiver compensation, and/or, adaptive transmitter compensation
  • the damage extraction module is used to obtain the convergence
  • an embodiment of the present application also provides an electronic device, including: at least one processor; a memory connected to the at least one processor in communication; the memory stores instructions that can be executed by the at least one processor, and the instructions are executed by at least one processor Executed by a processor, so that at least one processor can execute the above optical signal impairment extraction method.
  • an embodiment of the present application further provides a computer-readable storage medium storing a computer program, and implementing the above optical signal damage extraction method when the computer program is executed by a processor.
  • FIG. 1 is a schematic flowchart of a method for extracting optical signal damage according to an embodiment of the present application
  • FIG. 2 is a schematic structural diagram of a generalized linear equalizer provided according to an embodiment of the present application
  • Fig. 3 is a schematic structural diagram of an optical signal damage extraction device provided according to an embodiment of the present application.
  • Fig. 4 is a schematic structural diagram of an electronic device provided according to an embodiment of the present application.
  • the embodiment of the present application relates to a method for extracting optical signal damage. As shown in FIG. 1 , the method specifically includes the following steps.
  • Step 101 acquire the sampling data of the I channel and the Q channel after the received light is mixed.
  • Step 102 performing adaptive compensation on the sampling data of the I channel and the Q channel; wherein, the adaptive compensation includes adaptive receiver compensation, and/or adaptive transmitter compensation.
  • Step 103 acquiring the converged equalization tap coefficients obtained by adaptive compensation.
  • Step 104 Acquire the impairments of the I-path and the Q-path according to each equalization tap coefficient; wherein, the impairments include impairments at the receiving end corresponding to adaptive compensation, and/or impairments at the transmitting end.
  • the optical signal impairment extraction method of this embodiment is applied to an optical signal impairment extraction device of a coherent optical communication system.
  • a digital signal processing (Digital Signal Processing, referred to as "DSP") processing device composed of an end damage extraction module, it is used in conjunction with a coherent transceiver. Compensate and extract the IQ impairment existing in the front end of the coherent transceiver, so as to monitor the IQ impairment subsequently.
  • the optical signal damage extraction method of this embodiment can be used in the factory stage to calibrate the optical transceiver module skew damage calibration technology in the form of software or hardware, or as a monitoring module in the live network. Monitor the skew damage caused by module aging and temperature drift in the network, and report it to the network management unit to facilitate fault diagnosis and positioning. It can also integrate the entire set of DSP as a batch of modules for on-site diagnosis or factory stage test instrument.
  • a complete coherent optical communication system includes a transmitting end, a receiving end and an optical fiber channel.
  • the modulator modulates the data onto the optical carrier, through the transmission of the optical fiber channel, coherently detects it at the receiving end, uses the local light to mix with the received signal light (that is, the received light), and is sampled by the ADC , the signal becomes a discrete digital signal, digital signal processing is performed, and the signal is restored to obtain the transmitted data.
  • the equalization method based on 4x4MIMO and 4x2MIMO equalizer to compensate the skew of the receiving end can realize the extraction of skew at the receiving end, but the equalization method based on the generalized linear equalizer to compensate for the skew of the receiving end is not as intuitive as 4x4MIMO and 4x2MIMO, and it is difficult to realize the use of generalized linear equalizer.
  • the linear equalizer extracts the receiver skew.
  • the tap coefficient obtains the damage of the I channel and the Q channel, and after adaptively compensating the skew, the impairment of the I channel and the Q channel can be extracted, that is, the skew value of the I channel and the Q channel.
  • the damage of the extracted I road and Q road is the receiving end damage corresponding to the adaptive compensation, and/or, the transmitting end damage, realizes the receiving end of I road and Q road Impairment at the transmitting end, or at the transmitting end, or at the receiving end and at the transmitting end.
  • the DSP processing device acquires the sampling data of the I channel and the Q channel after the received light is mixed.
  • the sampling data of the I channel and the Q channel are double sampling data outputted through an analog-to-digital converter (ADC).
  • ADC analog-to-digital converter
  • the received light needs to be mixed by a 90-degree mixer to obtain the I-channel signal and the Q-channel signal of the received light, so that the sampling data of the two-channel signals can be obtained after being sampled by the ADC.
  • the DSP processing device performs adaptive compensation on the sampling data of the I channel and the Q channel.
  • the adaptive compensation includes adaptive receiver compensation, and/or adaptive transmitter compensation.
  • the generalized linear equalizer takes the two-way complex signals to obtain the conjugate, and then uses the complex signal and its conjugate items as the input of the 4x2MIMO equalizer, thereby Compensate for damage.
  • the generalized linear equalizer can be obtained by the first-order modification of the Volterra backward inverse equalizer, which can compensate the linear damage and IQ imbalance of the signal, that is, the IQ damage.
  • step 103 the DSP processing device acquires the converged equalization tap coefficients obtained by adaptive compensation.
  • each equalization tap coefficient includes: h xx , h xy , h yx , h yy , h xx* , h xy* , h yx* and h yy* , which are obtained according to the iterative results of the following formula :
  • x(k) and y(k) are the input signal sequence
  • x * (k) and y * (k) are the conjugate terms of x(k) and y(k) respectively
  • 0 ⁇ 1 is The iterative step size
  • e x and e y are error criteria, and its calculation can be selected according to different modulation formats and algorithm architectures.
  • the CMA algorithm can be selected for transverse mode modulation formats such as PDM-nPSK, and its error function can be expressed as :
  • RDE radial decision algorithm
  • R x (k) and R y (k) are the decision radius of the RDE algorithm.
  • common algorithms such as DD-LMS (decision-guided least mean square) can also use coefficient upgrade iterations, and the main difference lies in the selection of error criteria.
  • step 104 the DSP processing device acquires impairments of the I-way and the Q-way according to each equalization tap coefficient.
  • the impairments of the I-way and the Q-way are obtained according to the equalization tap coefficients, specifically: performing Fourier transform on each equalization tap coefficient, and calculating the argument angles of the I-way and Q-way respectively according to the Fourier transform results, for
  • the I-way and Q-way arguments are frequency derived to obtain the I-way and Q-way damage.
  • the DSP processing device first performs Fourier transform on the converged equalization tap coefficients to obtain:
  • ⁇ is the angular frequency, calculated by the following formula:
  • Ntap is the number of taps
  • RB is the baud rate of the signal
  • ros is the oversampling rate
  • the value is 2 for the double sampling signal
  • linspace is the average calculation.
  • the method before adaptively compensating the sampled data of the I channel and the Q channel, the method further includes: performing frequency offset compensation on the sampled data of the I channel and the Q channel compensated by the adaptive receiving end; Carrier phase recovery is performed on the sampled data of the I-channel and the Q-channel; adaptive compensation is performed on the sampled data of the I-channel and the Q-channel, including: adaptive transmitter compensation is performed on the sampled data of the I-channel and the Q-channel.
  • the DSP processing device is equipped with a frequency offset compensator to perform frequency offset compensation on the sampled data of the I channel and the Q channel compensated by the adaptive receiving end, and through the transmitter end compensator to perform frequency offset compensation on the I channel and the Q channel after the carrier phase recovery
  • the sampled data is adaptively compensated at the transmitter.
  • the transmitter compensator can adopt a generalized linear blind equalization structure similar to the previous receiver compensator, or a pilot-based generalized linear equalizer.
  • the DSP processing device performs Fourier transform on each transmit equalization tap coefficient through the transmitter damage extraction module connected with the transmitter compensator, and calculates the argument angles of the I road and the Q road respectively according to the Fourier transform results, and the I road and the Q road The frequency derivation of the amplitude angle is performed separately to obtain the transmitting end damage of the I channel and the Q channel.
  • the method further includes: performing demapping and bit error rate (Bit Error Rate) on the sampling data of the I road and the Q road after the adaptive compensation Ratio, referred to as "BER") calculation.
  • Bit Error Rate Bit Error Rate
  • BER adaptive compensation Ratio
  • a frequency-domain generalized linear equalizer is proposed. Compared with the generalized linear equalizer in time domain, it has lower complexity. Compared with the traditional 2x2 MIMO equalizer, in addition to inheriting the compensation function of polarization demultiplexing and polarization mode dispersion, it has the compensation capability of the front-end damage of the coherent transceiver (amplitude imbalance, phase imbalance and IQ skew); second, for The generalized linear equalizer (regardless of the time domain or the frequency domain) proposes a dispersion pre-compensation architecture. Under the dispersion pre-compensation architecture, it can be guaranteed that the generalized linear equalizer can achieve the right The damage compensation of the front end of the transceiver retains its ability to completely compensate the damage.
  • the embodiment of the present application also relates to an optical signal impairment extraction device, which includes: an analog-to-digital converter 301 , a generalized linear equalizer 302 and a receiver impairment extraction module 303 .
  • the analog-to-digital converter 301 is configured to obtain sampling data of the I channel and the Q channel after the received light is mixed.
  • the generalized linear equalizer 302 is configured to perform adaptive compensation on the sampling data of the I channel and the Q channel; wherein, the adaptive compensation includes adaptive receiver compensation, and/or adaptive transmitter compensation.
  • the receiving end damage extraction module 303 that is, the receiving end skew extraction module, is used to obtain the converged equalization tap coefficients obtained by adaptive compensation, and obtain the damage of the I path and the Q path according to each equalization tap coefficient; wherein, the damage includes and Adaptively compensate for corresponding impairments at the receiving end and/or impairments at the transmitting end.
  • each equalization tap coefficient to obtain the damage of I road and Q road specifically, carry out Fourier transform to each equalization tap coefficient; Calculate the argument angle of I road and Q road respectively according to Fourier transform result;
  • the I-way and Q-way arguments are frequency derived to obtain the I-way and Q-way damage.
  • each equalization tap coefficient includes: h xx , h xy , h yx , h yy , h xx* , h xy* , h yx* and h yy* , which are respectively obtained according to the iterative results of the following formula:
  • x(k) and y(k) are the input signal sequence
  • x * (k) and y * (k) are the conjugate terms of x(k) and y(k) respectively
  • 0 ⁇ 1 is The iteration step size
  • e x and e y are error criteria.
  • Carry out Fourier transform to each equalization tap coefficient comprise: calculate and obtain each Fourier transform result of each equalization tap coefficient according to the following formula:
  • conj(z) is the conjugate of the complex number z
  • arg(z) is the argument of the complex number z
  • the frequency derivation of the I-way and Q-way arguments is performed separately to obtain the damage of the I-way and Q-way, including:
  • ⁇ is the angular frequency
  • the device further includes: a frequency offset compensator 304 , a carrier phase recovery module 305 , a transmitter compensator 306 and a transmitter impairment extraction module 307 .
  • the frequency offset compensator 304 is configured to perform frequency offset compensation on the sampled data of the I channel and the Q channel compensated by the adaptive receiving end.
  • the carrier phase recovery module 305 is configured to recover the carrier phase of the sampled data of the I channel and the Q channel after frequency offset compensation.
  • the transmitter compensator 306 is configured to perform adaptive transmitter compensation on the sampled data of the I channel and the Q channel after the carrier phase is recovered.
  • the transmitting end impairment extraction module 307 that is, the transmitting end skew extraction module, is used to obtain the converged transmission equalization tap coefficients obtained by adaptive compensation, and obtain the transmission end impairments of the I path and the Q path according to each emission equalization tap coefficient.
  • the device further includes: a demapping and BER calculation module 308 .
  • the demapping and BER calculation module 308 is configured to perform demapping and bit error rate calculation on the adaptively compensated I-way and Q-way sampling data.
  • the embodiment of the present application also relates to an electronic device, as shown in FIG. 4 , including: at least one processor 401; a memory 402 connected in communication with at least one processor; The executed instructions are executed by at least one processor 401 in any one of the foregoing method embodiments.
  • the memory 402 and the processor 401 are connected by a bus, and the bus may include any number of interconnected buses and bridges, and the bus connects one or more processors 401 and various circuits of the memory 402 together.
  • the bus may also connect together various other circuits such as peripherals, voltage regulators, and power management circuits, all of which are well known in the art and therefore will not be further described herein.
  • the bus interface provides an interface between the bus and the transceivers.
  • a transceiver may be a single element or multiple elements, such as multiple receivers and transmitters, providing means for communicating with various other devices over a transmission medium.
  • the information processed by the processor 401 is transmitted on the wireless medium through the antenna, and further, the antenna also receives the information and transmits the information to the processor 401 .
  • Processor 401 is responsible for managing the bus and general processing, and may also provide various functions including timing, peripheral interface, voltage regulation, power management, and other control functions. Instead, memory 402 may be used to store information used by the processor when performing operations.
  • Embodiments of the present application relate to a computer-readable storage medium storing a computer program.
  • the above method embodiments are implemented when the computer program is executed by the processor.
  • the aforementioned storage media include: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), magnetic disk or optical disk and other media that can store program codes. .

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  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
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Abstract

Des modes de réalisation de la présente demande ont trait au domaine des communications optiques. L'invention concerne un procédé et un appareil d'extraction d'obliquité de signal optique, un dispositif électronique et un support de stockage. Dans la présente invention, le procédé d'extraction d'obliquité de signal optique comprend les étapes suivantes consistant à : acquérir des données d'échantillonnage d'un canal I et d'un canal Q après que la lumière reçue est mélangée ; réaliser une compensation d'extrémité de réception adaptative pour les données d'échantillonnage du canal I et du canal Q, la compensation adaptative comprenant la compensation d'extrémité de réception adaptative et/ou la compensation d'extrémité de transmission adaptative ; acquérir des coefficients de dérivation d'égalisation de réception convergent obtenus par la compensation d'extrémité de réception adaptative ; et acquérir des obliquités d'extrémité de réception du canal I et du canal Q conformément aux coefficients de dérivation d'égalisation de réception, les obliquités comprenant une obliquité d'extrémité de réception et/ou une obliquité d'extrémité de transmission correspondant à la compensation adaptative.
PCT/CN2022/121778 2021-10-11 2022-09-27 Procédé et appareil d'extraction d'obliquité de signal optique, dispositif électronique et support de stockage WO2023061213A1 (fr)

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