Optical signal processing apparatus, method and electronic device

Abstract

The application provides an optical signal processing device, method and electronic equipment, and relates to the technical field of communication. The optical signal processing device comprises: a coherent receiver; an intermediate processing module; a phase and frequency offset recovery module; a phase noise detection module configured to detect the spectral distribution of first phase noise in a signal output by the phase and frequency offset recovery module, wherein the first phase noise is phase noise introduced by XPM; a phase noise whitening module configured to perform whitening processing on the signal output by the phase and frequency offset recovery module according to the spectral distribution of the first phase noise, to obtain a first signal; and a forward error correction module. By converting the probability density distribution of the OSC and the phase noise introduced by the optical signal XPM from not subjecting to Gaussian distribution to subjecting to Gaussian distribution or near Gaussian distribution, the error correction performance of the FEC module can be recovered, and the cross-phase modulation damage can be inhibited while the existing optical signal receiving end structure design is compatible.

Description

Technical Field

[0001] This invention relates to the field of communication technology, and in particular to an optical signal processing apparatus, method, and electronic device. Background Technology

[0002] Currently, Dense Wavelength Division Multiplexing (DWDM) is widely used in global core network long-haul backbones and metropolitan area network (MAN) transmission systems, fully utilizing the enormous potential bandwidth of optical fibers to meet the growing demand for voice, data, and multimedia services. Backbone long-haul and MAN transmissions govern all the various service information within them, determining the overall network's operational status. To monitor network lines in a timely manner, detect faults, and resolve them promptly to ensure normal network operation, the concept of the Optical Supervisory Channel (OSC) has emerged. The primary function of the OSC is to monitor the transmission status of each channel within the system, such as... Figure 1 As shown, at the transmitting end, an OSC with a wavelength of 1510nm generated by this node is inserted and combined with the optical signal of the main channel for output; at the receiving end, the received optical signal is demultiplexed, and the OSC with a wavelength of 1510nm and the service channel optical signal are output separately. Frame synchronization bytes, service bytes, and overhead bytes used by network management are all transmitted through the optical monitoring channel.

[0003] The DWDM network management system manages the DWDM system by transmitting overhead bytes to other nodes or receiving overhead bytes from other nodes through the physical layer of the optical monitoring channel (OSC). It performs functions such as configuration management, fault management, performance management, and security management, and connects to upper-layer management systems, such as the Telecommunications Management Network (TMN). It holds a crucial position and role in current Optical Transport Networks (OTNs). Therefore, as the monitoring channel of the DWDM system, the OSC, when transmitting in the same direction as the main optical service signal, such as... Figure 2As shown, it should not affect the transmission performance of the main optical service signal. Typically, the OSC and the main optical service signal have a large wavelength separation, so it is assumed that it will not affect the main optical service. However, the inventors discovered in tests that in long-distance OTN networks, the OSC undergoes cross-phase modulation (XPM) with the signal light, leading to increased phase noise in the signal light and increased degradation in the transmission performance of the main optical service signal. Furthermore, the phase noise gradually accumulates with increasing transmission distance. Specifically, the phase noise introduced by XPM does not follow a Gaussian or near-Gaussian distribution, unlike the properties of Additive White Gaussian Noise (AWGN). The error correction coding currently used in OTN coherent systems is Soft Decision-Forward Error Correction (SD-FEC), which is designed based on AWGN channels. Therefore, when non-AWGN noise appears in the system, its error correction capability will decrease significantly, causing a further increase in channel cost, such as... Figure 3 As shown.

[0004] However, there is no solution in the existing technology for the problem of the transmission performance degradation of the main optical service signal caused by the phase noise introduced by OSC and optical signal XPM. Summary of the Invention

[0005] This invention provides an optical signal processing apparatus, method, and electronic device to solve the problem of transmission performance degradation of main optical service signals caused by phase noise introduced by OSC and optical signal XPM.

[0006] To solve the above-mentioned technical problems, the present invention is implemented as follows:

[0007] In a first aspect, embodiments of the present invention provide an optical signal processing apparatus, the optical signal processing apparatus comprising:

[0008] Coherent receiver;

[0009] An intermediate processing module, the first end of which is connected to the coherent receiver, the intermediate processing module including at least one of a dispersion compensation module, a clock recovery module, and a polarization demultiplexing module;

[0010] A phase and frequency offset recovery module, wherein a first end of the phase and frequency offset recovery module is connected to a second end of the intermediate processing module;

[0011] A phase noise detection module, wherein the first end of the phase noise detection module is connected to the second end of the phase and frequency offset recovery module, is used to detect the spectral distribution of the first phase noise in the signal output by the phase and frequency offset recovery module, wherein the first phase noise is the phase noise introduced by cross-phase modulation XPM;

[0012] A phase noise whitening module, wherein the first end of the phase noise whitening module is connected to the second end of the phase noise detection module, is used to whiten the signal output by the phase and frequency offset recovery module according to the spectral distribution of the first phase noise to obtain a first signal, wherein the spectral distribution of the second phase noise in the first signal satisfies the spectral distribution of additive Gaussian white noise, or the difference between the spectral distribution of the second phase noise and the spectral distribution of additive Gaussian white noise is less than a preset value;

[0013] A forward error correction module is provided, which is connected to the second end of the phase noise whitening module. In a second aspect, embodiments of the present invention provide an optical signal processing method, the optical signal processing method comprising:

[0014] Receive optical signals;

[0015] The optical signal is subjected to intermediate processing, which includes at least one of dispersion compensation, clock recovery, and polarization demultiplexing.

[0016] Phase and frequency offset recovery are performed on the intermediate processed signal;

[0017] The spectral distribution of the first phase noise in the phase and frequency offset recovered signal is detected, wherein the first phase noise is the phase noise introduced by cross-phase modulation (XPM).

[0018] The phase and frequency offset recovered signal is whitened according to the spectral distribution of the first phase noise to obtain a first signal, wherein the spectral distribution of the second phase noise in the first signal satisfies the additive white Gaussian noise spectral distribution, or the difference between the spectral distribution of the second phase noise and the additive white Gaussian noise spectral distribution is less than a preset value.

[0019] Forward error correction is performed on the first signal.

[0020] Thirdly, embodiments of the present invention provide an electronic device, including a coherent receiver and a processor.

[0021] The coherent receiver is used to receive optical signals;

[0022] The processor is configured to perform intermediate processing on the optical signal, the intermediate processing including at least one of dispersion compensation, clock recovery, and polarization demultiplexing; perform phase and frequency offset recovery on the intermediate processed signal; detect the spectral distribution of a first phase noise in the phase and frequency offset recovered signal, wherein the first phase noise is phase noise introduced by cross-phase modulation (XPM); and perform whitening processing on the phase and frequency offset recovered signal according to the spectral distribution of the first phase noise to obtain a first signal, wherein the spectral distribution of a second phase noise in the first signal satisfies the additive white Gaussian noise spectral distribution, or the difference between the spectral distribution of the second phase noise and the additive white Gaussian noise spectral distribution is less than a preset value; and perform forward error correction on the first signal.

[0023] Fourthly, embodiments of the present invention provide an electronic device, including: a processor, a memory, and a program stored in the memory and executable on the processor, wherein the program, when executed by the processor, implements the steps of the optical signal processing method described in the second aspect above.

[0024] Fifthly, embodiments of the present invention provide a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the steps of the optical signal processing method described in the second aspect above.

[0025] In this embodiment, the phase noise detection module detects the spectral distribution of the first phase noise in the signal output by the phase and frequency offset recovery module. This first phase noise is the phase noise introduced by cross-phase modulation (XPM). The phase noise whitening module whitens the signal output by the phase and frequency offset recovery module based on the spectral distribution of the first phase noise, obtaining a first signal. The spectral distribution of the second phase noise in the first signal satisfies the additive white Gaussian noise spectral distribution, or the difference between the spectral distribution of the second phase noise and the additive white Gaussian noise spectral distribution is less than a preset value. That is, the phase noise detection module detects the phase noise, and the phase noise whitening module transforms the probability density distribution of the phase noise introduced by OSC and the optical signal XPM from a non-Gaussian distribution to a Gaussian or near-Gaussian distribution. This restores the error correction performance of the FEC module, suppresses cross-phase modulation impairments while maintaining compatibility with existing optical signal receiver structural designs, and improves transmission performance. Attached Figure Description

[0026] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is a schematic diagram showing the location of the OSC in the DWDM system according to an embodiment of the present invention;

[0028] Figure 2 This is a schematic diagram of the spectrum of OSC and main optical service signals coexisting, provided in an embodiment of the present invention;

[0029] Figure 3 This is a schematic diagram showing the channel cost of each signal light as a function of wavelength when the OSC is on and off, provided by an embodiment of the present invention.

[0030] Figure 4 This is a schematic diagram of the structure of an optical signal processing device provided in an embodiment of the present invention;

[0031] Figure 5 This is a schematic diagram of the structure of a related receiver provided in an embodiment of the present invention;

[0032] Figure 6 This is a schematic diagram of another optical signal processing device provided in an embodiment of the present invention;

[0033] Figure 7 This is a schematic diagram of the phase noise detection module provided in an embodiment of the present invention;

[0034] Figure 8 This is a schematic diagram of the phase noise whitening module provided in an embodiment of the present invention;

[0035] Figure 9 This is a schematic diagram of the phase noise whitening filter provided in an embodiment of the present invention;

[0036] Figure 10a This is a schematic diagram of the first phase noise power spectral density distribution provided in an embodiment of the present invention;

[0037] Figure 10b This is a schematic diagram of the frequency response distribution of the phase noise whitening module provided in an embodiment of the present invention;

[0038] Figure 10c This is a schematic diagram of the noise power spectral density distribution after processing by the phase noise whitening module provided in this embodiment of the invention;

[0039] Figure 11 This is a flowchart of an optical signal processing method provided in an embodiment of the present invention;

[0040] Figure 12 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0041] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0042] See Figure 4 , Figure 4 This is a schematic diagram of the structure of an optical signal processing device provided in an embodiment of the present invention. Figure 4 As shown, the optical signal processing device 100 provided in this embodiment includes:

[0043] Coherent receiver 10;

[0044] An intermediate processing module 20 is provided, with its first end connected to the coherent receiver 10. The intermediate processing module 20 includes at least one of a dispersion compensation module, a clock recovery module, and a polarization demultiplexing module.

[0045] Phase and frequency offset recovery module 30, wherein the first end of the phase and frequency offset recovery module 30 is connected to the second end of the intermediate processing module;

[0046] A phase noise detection module 40, the first end of which is connected to the second end of the phase and frequency offset recovery module 30, is used to detect the spectral distribution of the first phase noise in the signal output by the phase and frequency offset recovery module 30, wherein the first phase noise is the phase noise introduced by cross-phase modulation XPM;

[0047] A phase noise whitening module 50 is provided, with its first end connected to the second end of the phase noise detection module 40. The module is used to whiten the signal output by the phase and frequency offset recovery module 30 according to the spectral distribution of the first phase noise to obtain a first signal. The spectral distribution of the second phase noise in the first signal satisfies the additive white Gaussian noise spectral distribution, or the difference between the spectral distribution of the second phase noise and the additive white Gaussian noise spectral distribution is less than a preset value.

[0048] A forward error correction module 60 is connected to the second end of the phase noise whitening module 50.

[0049] The coherent receiver 10 described above can be used to receive optical signals, and it can be any existing coherent receiver; this embodiment does not limit its structural composition. For example, an optional coherent receiver structure can be as follows: Figure 5 As shown, it includes a polarization beam splitter 11, a 90° mixer 12, a balanced light detector array 13, and an analog-to-digital converter (ADC) 14.

[0050] The aforementioned intermediate processing module 20 may include, but is not limited to, at least one of a dispersion compensation module, a clock recovery module, and a polarization demultiplexing module. The dispersion compensation module can be used to compensate for the dispersion of the received signal. For example, dispersion compensation can be achieved using dispersion compensation fibers, fiber optic gratings, etc., or by executing a corresponding dispersion compensation algorithm using a digital signal processor (DSP). The clock recovery module can be used to recover the clock of the received signal to track and eliminate the frequency offset between the transmitting clock and the receiver ADC sampling clock, as well as the phase jitter of the sampling clock. The polarization demultiplexing module can be used to demultiplex the received signal to cancel interference between polarization signals.

[0051] It should be noted that, in cases where the aforementioned intermediate processing modules include, but are not limited to, a dispersion compensation module, a clock recovery module, and a polarization demultiplexing module, these modules can be connected in series in any arbitrary order; this embodiment does not impose any limitation on this. For example, as... Figure 6 As shown, the first terminal of the coherent receiver 10 is connected to the first terminal of the dispersion compensation module 21, the second terminal of the dispersion compensation module 21 is connected to the first terminal of the clock recovery module 22, the second terminal of the clock recovery module 22 is connected to the first terminal of the polarization demultiplexing module 23, and the second terminal of the polarization demultiplexing module 23 is connected to the phase and frequency offset recovery module 30. Alternatively, the first terminal of the coherent receiver 10 is connected to the first terminal of the clock recovery module, the second terminal of the clock recovery module is connected to the first terminal of the dispersion compensation module, the second terminal of the dispersion compensation module is connected to the first terminal of the polarization demultiplexing module, and the second terminal of the polarization demultiplexing module is connected to the phase and frequency offset recovery module 30.

[0052] The aforementioned phase and frequency offset recovery module 30 can be used to recover the phase and frequency offset of the received signal to correctly demodulate the received signal. The aforementioned phase noise detection module 40 can be used to detect the spectral distribution of the phase noise introduced by the XPM in the signal output by the phase and frequency offset recovery module 30. The aforementioned phase noise whitening module 50 can be used to whiten the signal output by the phase and frequency offset recovery module 30 according to the spectral distribution of the phase noise introduced by the XPM, so that the noise in the whitened signal satisfies or approximately satisfies the spectral distribution of additive white Gaussian noise. The difference between the spectral distribution of the second phase noise and the spectral distribution of additive white Gaussian noise may include, but is not limited to, the variance or standard deviation between the spectral distributions of the second phase noise and additive white Gaussian noise. These preset values ​​can be reasonably set according to actual needs.

[0053] The aforementioned forward error correction module 60 can be used to perform forward error correction processing on the whitened signal based on forward error correction coding.

[0054] It should be noted that the intermediate processing module 20, phase and frequency offset recovery module 30, phase noise detection module 40, phase noise whitening module 50 and forward error correction module 60 mentioned above can be hardware modules or implemented by the corresponding algorithm executed by the DSP. This embodiment does not limit this.

[0055] The optical signal processing device provided in this embodiment detects the spectral distribution of a first phase noise in the signal output by the phase and frequency offset recovery module through a phase noise detection module. This first phase noise is the phase noise introduced by cross-phase modulation (XPM). A phase noise whitening module whitens the signal output by the phase and frequency offset recovery module based on the spectral distribution of the first phase noise to obtain a first signal. The spectral distribution of a second phase noise in the first signal satisfies the additive white Gaussian noise spectral distribution, or the difference between the spectral distribution of the second phase noise and the additive white Gaussian noise spectral distribution is less than a preset value. In other words, the phase noise detection module detects the phase noise, and the phase noise whitening module transforms the probability density distribution of the phase noise introduced by OSC and the optical signal XPM from a non-Gaussian distribution to a Gaussian or near-Gaussian distribution. This restores the error correction performance of the FEC module and suppresses cross-phase modulation impairment while maintaining compatibility with existing optical signal receiver structural designs.

[0056] Optionally, such as Figure 7 As shown, the phase noise detection module 40 may include:

[0057] The first arithmetic module, also known as the fourth power arithmetic module 41, is used to perform fourth power arithmetic on the signal output by the phase and frequency offset recovery module.

[0058] Delay unit 42 is used to delay the signal output by the first arithmetic module;

[0059] The second arithmetic module 43 is used to multiply the signal output by the first arithmetic module and the signal output by the delay unit.

[0060] The third arithmetic module, also known as the Fourier transform module 44, is used to perform a Fourier transform on the signal output by the second arithmetic module to obtain the spectral distribution of the first phase noise.

[0061] In this embodiment, the delay duration of the delay device can be reasonably set according to the optical signal rate. For example, the delay duration of the delay device can be between 1 symbol period and 100 symbol periods.

[0062] Specifically, it can be like Figure 7 As shown, the fourth power operation module 41 performs a fourth power operation on the main signal after phase and frequency offset recovery, and inputs the signal after the fourth power operation into the delay unit 42 for delay processing. The signal after the delay processing and the signal after the fourth power operation are input into the second operation module 43 for multiplication, and the result of the multiplication is input into the Fourier transform module 44 for Fourier transform to obtain the spectral distribution of the phase noise introduced by OSC and optical signal XPM.

[0063] This embodiment performs fourth power operations, delay processing, multiplication, and Fourier transform on the main signal after phase and frequency offset recovery. The structure is relatively simple and can quickly and accurately obtain the spectral distribution of the phase noise introduced by XPM.

[0064] Optionally, such as Figure 8 As shown, the phase noise whitening module 50 includes:

[0065] The filter parameter generator 51 is used to generate filter parameters based on the spectral distribution of the first phase noise, wherein the filter parameters include at least one of the number of filter taps and the filter tap coefficients.

[0066] A phase noise whitening filter 52 is used to whiten and filter the signal output by the phase and frequency offset recovery module to obtain the first signal, wherein the parameters of the phase noise whitening filter 52 are configured according to the filter parameters.

[0067] For example, the filter parameter generator 51 can determine a frequency response that is inversely related to the spectral distribution of the first phase noise based on the spectral distribution of the first phase noise, and determine filter parameters based on the frequency response that is inversely related to the spectral distribution of the first phase noise, so that the phase noise whitening filter 52 configured with the filter parameters outputs a frequency response that is inversely related to the spectral distribution of the first phase noise; or the filter parameter generator 51 can determine filter parameters based on the spectral distribution of the first phase noise and a desired noise spectral distribution, so that the spectral distribution of the phase noise in the signal filtered by the phase noise whitening filter 52 configured with the filter parameters satisfies or approximately satisfies the desired noise spectral distribution. The desired noise spectral distribution may be an additive white Gaussian noise spectral distribution.

[0068] Optionally, the second end of the phase noise whitening filter 52 can also be connected to the third end of the filter parameter generator 51. In this way, the filter parameter generator 51 can continuously adjust the filter parameters based on the signal output by the phase noise whitening filter 52 until the spectral distribution of the phase noise in the signal output by the phase noise whitening filter 52 configured based on the adjusted filter parameters satisfies or approximately satisfies the desired noise spectral distribution.

[0069] Specifically, it can be like Figure 8 As shown, the filter parameter generator 51 generates N filter parameters, namely parameters h(0) to h(N-1), based on the spectral distribution of the phase noise, where N is a positive integer, and as shown in the figure. Figure 9 As shown, the phase noise whitening filter 52 is configured according to parameters h(0) to h(N-1). The configured phase noise whitening filter 52 filters the main signal output by the phase and frequency offset recovery module and outputs the filtered main signal. The spectral distribution of the phase noise in the filtered main signal satisfies or approximately satisfies the desired noise spectral distribution.

[0070] The phase noise whitening module in this embodiment includes a filter parameter generator and a phase noise whitening filter. The filter parameter generator is used to generate filter parameters based on the spectral distribution of the first phase noise. The phase noise whitening filter configured according to the filter parameters is used to perform whitening filtering on the signal output by the phase and frequency offset recovery module. This not only achieves a relatively simple structure but also ensures a good whitening filtering effect.

[0071] Optionally, the phase noise whitening filter is used to apply a first frequency response to the signal output by the phase and frequency offset recovery module to obtain the first signal, wherein the first frequency response is a frequency response opposite to the spectral distribution of the first phase noise.

[0072] In this embodiment, a phase noise whitening filter is used to apply a frequency response that is opposite to the spectral distribution of the first phase noise to the signal output by the phase and frequency offset recovery module, so that the phase noise introduced by the XPM conforms to the AWGN distribution, thereby restoring the FEC error correction capability.

[0073] For example, such as Figures 10a to 10c As shown, where, Figure 10a The diagram shows the power spectral density distribution of the first phase noise. Figure 10b The diagram shows the frequency response distribution of the phase noise whitening module. Figure 10c This shows the power spectral density distribution of the noise filtered by the phase noise whitening module. The frequency response output by the phase noise whitening module is opposite to the power spectral density of the first phase noise, thus... Figure 10b The frequency response of the phase noise whitening module shown is applied to the signals output by the phase and frequency offset recovery modules, and the following can be obtained: Figure 10c The noise power spectral density after filtering by the phase noise whitening module is shown.

[0074] In this embodiment, a phase noise whitening filter is used to apply a frequency response to the signal output by the phase and frequency offset recovery module that is opposite to the spectral distribution of the first phase noise, so that the phase noise introduced by the XPM conforms to the AWGN distribution, which is relatively simple and convenient to implement.

[0075] It should be noted that the optical signal processing device provided in this embodiment can be set at the receiving end of the optical signal communication system. For example, a phase noise detection module and a phase noise whitening module can be added to the optical digital signal processing (oDSP) at the receiving end of the optical signal communication system. The phase noise detection module and the phase noise whitening module can transform the probability density distribution of the phase noise introduced by OSC and optical signal XPM from a non-Gaussian distribution to a Gaussian or near-Gaussian distribution. This minimizes the changes to the overall design of the optical signal communication system and, while retaining the original design of the FEC error correction code, suppresses the damage introduced by XPM to the optical signal communication system.

[0076] See Figure 11 , Figure 11 This is a flowchart of an optical signal processing method provided in an embodiment of the present invention, such as... Figure 11 As shown, the optical signal processing method provided in this embodiment includes the following steps:

[0077] Step 1101: Receive optical signal.

[0078] In this embodiment, optical signals can be received by a coherent receiver. For details on the coherent receiver, please refer to the relevant content of the aforementioned optical signal processing device embodiment, which will not be repeated here.

[0079] Step 1102: Perform intermediate processing on the optical signal, the intermediate processing including at least one of dispersion compensation, clock recovery and polarization demultiplexing.

[0080] In this embodiment, the optical signal can be processed by an intermediate processing module. For details on the intermediate processing module, please refer to the relevant content of the aforementioned optical signal processing device embodiment, which will not be repeated here.

[0081] Step 1103: Perform phase and frequency offset recovery on the intermediate processed signal.

[0082] In this embodiment, the intermediate processed signal can be phase and frequency offset restored by a phase and frequency offset recovery module. For details on the phase and frequency offset recovery module, please refer to the relevant content of the aforementioned optical signal processing device embodiment, which will not be repeated here.

[0083] Step 1104: Detect the spectral distribution of the first phase noise in the signal after phase and frequency offset recovery, wherein the first phase noise is the phase noise introduced by cross-phase modulation (XPM).

[0084] In this embodiment, the spectral distribution of the first phase noise in the signal after phase and frequency offset recovery can be detected by the phase noise detection module. For relevant descriptions of the phase noise detection module, please refer to the relevant content of the aforementioned optical signal processing device embodiment, which will not be repeated here.

[0085] Step 1105: Whiten the phase and frequency offset recovered signal according to the spectral distribution of the first phase noise to obtain a first signal, wherein the spectral distribution of the second phase noise in the first signal satisfies the additive white Gaussian noise spectral distribution, or the difference between the spectral distribution of the second phase noise and the spectral distribution of the additive white Gaussian noise is less than a preset value.

[0086] In this embodiment, the phase and frequency offset recovered signal can be whitened by the phase noise whitening module according to the spectral distribution of the first phase noise to obtain the first signal. For relevant descriptions of the phase noise whitening module, please refer to the relevant content of the aforementioned optical signal processing device embodiment, which will not be repeated here.

[0087] Step 1106: Perform forward error correction on the first signal.

[0088] In this embodiment, the first signal can be forward-corrected by a forward error correction module. For details on the forward error correction module, please refer to the relevant content of the aforementioned optical signal processing device embodiment, which will not be repeated here.

[0089] The optical signal processing method provided in this embodiment detects the spectral distribution of the first phase noise in the phase and frequency offset recovered signal, wherein the first phase noise is the phase noise introduced by cross-phase modulation (XPM); and performs whitening processing on the phase and frequency offset recovered signal according to the spectral distribution of the first phase noise to obtain a first signal, wherein the spectral distribution of the second phase noise in the first signal satisfies the additive white Gaussian noise spectral distribution, or the difference between the spectral distribution of the second phase noise and the additive white Gaussian noise spectral distribution is less than a preset value, that is, the probability density distribution of the phase noise introduced by OSC and optical signal XPM is transformed from not following a Gaussian distribution to following a Gaussian distribution or a near-Gaussian distribution, so as to restore the FEC error correction performance and achieve the suppression of cross-phase modulation damage.

[0090] Optionally, detecting the spectral distribution of the first phase noise in the signal after phase and frequency offset recovery includes:

[0091] Perform a fourth power operation on the phase and frequency offset recovered signal;

[0092] The signal after the fourth power operation is delayed;

[0093] Multiply the delayed signal and the signal obtained by the fourth power operation;

[0094] Perform a Fourier transform on the multiplied signal to obtain the spectral distribution of the first phase noise.

[0095] In this embodiment, the main signal after phase and frequency offset recovery is subjected to a fourth power operation, the signal after the fourth power operation is delayed, the delayed signal and the signal after the fourth power operation are multiplied, and the result of the multiplication is subjected to a Fourier transform to obtain the spectral distribution of the phase noise introduced by the OSC and the optical signal XPM. This method can obtain the spectral distribution of the phase noise introduced by the XPM relatively quickly and accurately.

[0096] Optionally, the step of whitening the phase and frequency offset recovered signal according to the spectral distribution of the first phase noise to obtain the first signal includes:

[0097] Filter parameters are generated based on the spectral distribution of the first phase noise, wherein the filter parameters include at least one of the number of filter taps and the filter tap coefficients;

[0098] The first signal is obtained by whitening the phase and frequency offset recovered signal using a phase noise whitening filter, wherein the parameters of the phase noise whitening filter are configured according to the filter parameters.

[0099] For example, a frequency response that is inversely related to the spectral distribution of the first phase noise can be determined based on the spectral distribution of the first phase noise, and filter parameters can be determined based on this inverse frequency response, so that the phase noise whitening filter configured with the filter parameters outputs a frequency response that is inversely related to the spectral distribution of the first phase noise; or the filter parameters can be determined based on the spectral distribution of the first phase noise and a desired noise spectral distribution, so that the spectral distribution of the phase noise in the signal filtered by the phase noise whitening filter configured with the filter parameters satisfies or approximately satisfies the desired noise spectral distribution. The desired noise spectral distribution can be an additive white Gaussian noise spectral distribution.

[0100] In this embodiment, filter parameters are generated based on the spectral distribution of the first phase noise. The phase noise whitening filter configured according to the filter parameters is used to perform whitening filtering on the signal after phase and frequency offset recovery. This not only achieves a relatively simple structure but also ensures a good whitening filtering effect.

[0101] Optionally, the phase noise whitening filter is used to apply a first frequency response to the signal after phase and frequency offset recovery to obtain the first signal, wherein the first frequency response is a frequency response opposite to the spectral distribution of the first phase noise.

[0102] In this embodiment, a phase noise whitening filter is used to apply a frequency response to the signal output by the phase and frequency offset recovery module that is opposite to the spectral distribution of the first phase noise, so that the phase noise introduced by the XPM conforms to the AWGN distribution, which is relatively simple and convenient to implement.

[0103] It should be noted that each process of the optical signal processing method embodiment provided in this embodiment can be implemented by the above-mentioned optical signal processing device. The technical features correspond one-to-one and can achieve the same technical effect. To avoid repetition, it will not be described again here.

[0104] This invention also provides an electronic device, including: a processor, a memory, and a program stored in the memory and executable on the processor. When the program is executed by the processor, it implements the various processes of the above-described optical signal processing method embodiments and achieves the same technical effect. To avoid repetition, it will not be described again here.

[0105] For details, see Figure 12The present invention also provides an electronic device, including a bus 1201, a coherent receiver 1202, an antenna 1203, a bus interface 1204, a processor 1205, and a memory 1206.

[0106] The coherent receiver 1202 is used to receive optical signals;

[0107] The processor 1205 is configured to perform intermediate processing on the optical signal, the intermediate processing including at least one of dispersion compensation, clock recovery, and polarization demultiplexing; perform phase and frequency offset recovery on the intermediate processed signal; detect the spectral distribution of a first phase noise in the phase and frequency offset recovered signal, wherein the first phase noise is phase noise introduced by cross-phase modulation (XPM); perform whitening processing on the phase and frequency offset recovered signal according to the spectral distribution of the first phase noise to obtain a first signal, wherein the spectral distribution of a second phase noise in the first signal satisfies the additive white Gaussian noise spectral distribution, or the difference between the spectral distribution of the second phase noise and the additive white Gaussian noise spectral distribution is less than a preset value; and perform forward error correction on the first signal.

[0108] Optionally, the processor 1205 is further configured to:

[0109] Perform a fourth power operation on the phase and frequency offset recovered signal;

[0110] The signal after the fourth power operation is delayed;

[0111] Multiply the delayed signal and the signal obtained by the fourth power operation;

[0112] Perform a Fourier transform on the multiplied signal to obtain the spectral distribution of the first phase noise.

[0113] Optionally, the processor 1205 is further configured to:

[0114] Filter parameters are generated based on the spectral distribution of the first phase noise, wherein the filter parameters include at least one of the number of filter taps and the filter tap coefficients;

[0115] The first signal is obtained by whitening the phase and frequency offset recovered signal using a phase noise whitening filter, wherein the parameters of the phase noise whitening filter are configured according to the filter parameters.

[0116] Optionally, the phase noise whitening filter is used to apply a first frequency response to the signal after phase and frequency offset recovery to obtain the first signal, wherein the first frequency response is a frequency response opposite to the spectral distribution of the first phase noise.

[0117] exist Figure 12 In this document, a bus architecture (represented by bus 1201) is used. Bus 1201 may include any number of interconnected buses and bridges, linking various circuits including one or more processors represented by processor 1205 and memory represented by memory 1206. Bus 1201 may also link various other circuits such as peripheral devices, voltage regulators, and power management circuits, which are well known in the art and therefore will not be described further herein. Bus interface 1204 provides an interface between bus 1201 and coherent receiver 1202. Coherent receiver 1202 may be a single element or multiple elements, such as multiple receivers, providing a unit for communicating with various other devices over a transmission medium. Data processed by processor 1205 is transmitted over a wireless medium via antenna 1203, which further receives data and transmits it to processor 1205.

[0118] Processor 1205 is responsible for managing bus 1201 and general processing, and can also provide various functions, including timing, peripheral interface, voltage regulation, power management, and other control functions. Memory 1206 can be used to store data used by processor 1205 during operation.

[0119] Optionally, the processor 1205 can be a DSP, CPU, ASIC, FPGA, or CPLD.

[0120] This invention also provides a computer-readable storage medium storing a computer program. When executed by a processor, this computer program implements the various processes of the above-described optical signal processing method embodiments and achieves the same technical effects. To avoid repetition, it will not be described again here. The computer-readable storage medium may be a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0121] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0122] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes several instructions to cause a terminal (which may be a mobile phone, computer, server, air conditioner, or network device, etc.) to execute the methods of the various embodiments of the present invention.

[0123] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of the present invention.

Claims

1. An optical signal processing device, characterized in that, The device includes: Coherent receiver; An intermediate processing module, the first end of which is connected to the coherent receiver, the intermediate processing module including at least one of a dispersion compensation module, a clock recovery module, and a polarization demultiplexing module; A phase and frequency offset recovery module, wherein a first end of the phase and frequency offset recovery module is connected to a second end of the intermediate processing module; A phase noise detection module, wherein the first end of the phase noise detection module is connected to the second end of the phase and frequency offset recovery module, is used to detect the spectral distribution of the first phase noise in the signal output by the phase and frequency offset recovery module, wherein the first phase noise is the phase noise introduced by cross-phase modulation XPM; A phase noise whitening module, wherein the first end of the phase noise whitening module is connected to the second end of the phase noise detection module, is used to whiten the signal output by the phase and frequency offset recovery module according to the spectral distribution of the first phase noise to obtain a first signal, wherein the spectral distribution of the second phase noise in the first signal satisfies the spectral distribution of additive Gaussian white noise, or the difference between the spectral distribution of the second phase noise and the spectral distribution of additive Gaussian white noise is less than a preset value; A forward error correction module is provided, which is connected to the second end of the phase noise whitening module.

2. The apparatus according to claim 1, characterized in that, The phase noise detection module includes: The first arithmetic module is used to perform a fourth power operation on the signal output by the phase and frequency offset recovery module. A delay unit is used to delay the signal output by the first arithmetic module; The second arithmetic module is used to multiply the signal output by the first arithmetic module and the signal output by the delay unit. The third arithmetic module is used to perform a Fourier transform on the signal output by the second arithmetic module to obtain the spectral distribution of the first phase noise.

3. The apparatus according to claim 1, characterized in that, The phase noise whitening module includes: A filter parameter generator is used to generate filter parameters based on the spectral distribution of the first phase noise, wherein the filter parameters include at least one of the number of filter taps and the filter tap coefficients; A phase noise whitening filter is used to whiten and filter the signal output by the phase and frequency offset recovery module to obtain the first signal, wherein the parameters of the phase noise whitening filter are configured according to the filter parameters.

4. The apparatus according to claim 3, characterized in that, The phase noise whitening filter is used to apply a first frequency response to the signal output by the phase and frequency offset recovery module to obtain the first signal, wherein the first frequency response is a frequency response that is opposite to the spectral distribution of the first phase noise.

5. An optical signal processing method, characterized in that, The method includes: Receive optical signals; The optical signal is subjected to intermediate processing, which includes at least one of dispersion compensation, clock recovery, and polarization demultiplexing. Phase and frequency offset recovery are performed on the intermediate processed signal; The spectral distribution of the first phase noise in the phase and frequency offset recovered signal is detected, wherein the first phase noise is the phase noise introduced by cross-phase modulation (XPM). The phase and frequency offset recovered signal is whitened according to the spectral distribution of the first phase noise to obtain a first signal, wherein the spectral distribution of the second phase noise in the first signal satisfies the additive white Gaussian noise spectral distribution, or the difference between the spectral distribution of the second phase noise and the additive white Gaussian noise spectral distribution is less than a preset value. Forward error correction is performed on the first signal.

6. The method according to claim 5, characterized in that, The detection of the spectral distribution of the first phase noise in the signal after phase and frequency offset recovery includes: Perform a fourth power operation on the phase and frequency offset recovered signal; The signal after the fourth power operation is delayed; Multiply the delayed signal and the signal after the fourth power operation; Perform a Fourier transform on the multiplied signal to obtain the spectral distribution of the first phase noise.

7. The method according to claim 5, characterized in that, The step of whitening the phase and frequency offset recovered signal according to the spectral distribution of the first phase noise to obtain the first signal includes: Filter parameters are generated based on the spectral distribution of the first phase noise, wherein the filter parameters include at least one of the number of filter taps and the filter tap coefficients; The first signal is obtained by whitening the phase and frequency offset recovered signal using a phase noise whitening filter, wherein the parameters of the phase noise whitening filter are configured according to the filter parameters.

8. The method according to claim 7, characterized in that, The phase noise whitening filter is used to apply a first frequency response to the signal after phase and frequency offset recovery to obtain the first signal, wherein the first frequency response is a frequency response opposite to the spectral distribution of the first phase noise.

9. An electronic device, characterized in that, Including coherent receivers and processors, The coherent receiver is used to receive optical signals; The processor is configured to perform intermediate processing on the optical signal, the intermediate processing including at least one of dispersion compensation, clock recovery, and polarization demultiplexing; perform phase and frequency offset recovery on the intermediate processed signal; detect the spectral distribution of a first phase noise in the phase and frequency offset recovered signal, wherein the first phase noise is phase noise introduced by cross-phase modulation (XPM); and perform whitening processing on the phase and frequency offset recovered signal according to the spectral distribution of the first phase noise to obtain a first signal, wherein the spectral distribution of a second phase noise in the first signal satisfies the additive white Gaussian noise spectral distribution, or the difference between the spectral distribution of the second phase noise and the additive white Gaussian noise spectral distribution is less than a preset value; and perform forward error correction on the first signal.

10. An electronic device, characterized in that, include: A processor, a memory, and a program stored in the memory and executable on the processor, wherein the program, when executed by the processor, implements the steps of the method as described in any one of claims 5 to 6.

11. A computer-readable storage medium having a computer program stored thereon, the computer program, when executed by a processor, implementing the steps of the method of any one of claims 5-8.

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