CN114629766B - Symbol judgment method, device, electronic equipment and storage medium in optical fiber communication - Google Patents

Abstract

The present invention provides a symbol judgment method, device, electronic equipment and storage medium in optical fiber communication. The symbol judgment method in optical fiber communication includes: receiving an optical signal and a local carrier signal, and based on the optical signal and the local carrier signal, generating an quadrature modulation signal; dividing the quadrature modulation signal into two signals; based on the partial response filter, the noise variance of the two signals, and the probability value of the corresponding symbol of the two signals, determining a symbol decision A loss function: based on the sign decision loss function, process the two-way signals to obtain sign decision results of the two-way signals. The symbol judging method, device, electronic equipment and storage medium in optical fiber communication provided by the present invention can solve the defect of wrong judgment of multi-signal point symbols in the prior art, and improve the accuracy of symbol judgment in optical fiber communication.

Description

Symbol judgment method, device, electronic equipment and storage medium in optical fiber communication

technical field

The invention relates to the technical field of signal processing, in particular to a symbol judgment method, device, electronic equipment and storage medium in optical fiber communication.

Background technique

With the increasing requirements of high-speed and large-capacity optical fiber communication systems for high spectral efficiency, probabilistic shaping technology has become the mainstream of high-speed and long-distance transmission technology, and has been adopted by relevant international standards organizations as one of the technical standards for long-distance transmission. . However, the impact of probabilistic shaping technology on traditional symbol decision technology limits the transmission performance of optical signals, and the solution to this problem lacks relevant theoretical and experimental support work. In order to effectively improve the system spectrum efficiency and transmission performance, the impact of probability shaping technology on symbol decision technology needs to be paid attention to, and corresponding solutions need to be put forward urgently.

The probabilistic shaping technology will cause the symbol decision boundary to shift from the original decision boundary, resulting in more signal points being misjudged and causing more obvious performance damage.

Contents of the invention

The present invention provides a symbol judgment method, device, electronic equipment and storage medium in optical fiber communication, which are used to solve the defect of wrong judgment of multi-signal point symbols in the prior art, and improve the accuracy of symbol judgment in optical fiber communication.

The present invention provides a symbol judgment method in optical fiber communication, comprising:

receiving an optical signal and a local carrier signal, and generating a quadrature modulation signal based on the optical signal and the local carrier signal;

dividing the quadrature modulation signal into two signals;

Based on the partial response filter, the noise variance of the two-way signals, and the probability value of the corresponding symbol of the two-way signals, determine a symbol decision loss function;

Based on the sign decision loss function, the two signals are processed to obtain sign decision results of the two signals.

According to the symbol judgment method in optical fiber communication provided by the present invention, it also includes:

Traverse the preset range of tap coefficients, and determine the tap coefficients with the lowest bit error rate of the symbol decision result as optimized coefficients;

Based on the optimized coefficients, the partial response filter is optimized.

According to the symbol decision method in optical fiber communication provided by the present invention, the symbol decision loss function is determined based on the partial response filter, the noise variance of the two-way signals, and the probability value of the corresponding symbol of the two-way signals, including:

The sign decision loss function is determined based on the following formula:

Among them, AM is the cumulative metric value corresponding to the symbol decision loss function, which is used to select the best symbol sequence; Y _k is the symbol corresponding to the two signals, HP _PF is the partial response filter, X is the candidate sequence, σ ² is the two The noise variance of the channel signal, p(X _k ) is the probability of the symbol decision result X _k .

According to the symbol decision method in optical fiber communication provided by the present invention, the two-way signals are processed based on the symbol decision loss function, and the sign decision results of the two-way signals are obtained, including:

Based on the symbol decision loss function, determine the bit sequence corresponding to the minimum cumulative metric value among the two signals, which is the decision result of the two signals.

According to the symbol decision method in optical fiber communication provided by the present invention, said dividing said quadrature modulation signal into two signals includes:

Perform clock signal recovery and equalization processing on the quadrature modulation signal, eliminate the clock frequency difference between the quadrature modulation signal corresponding to the arbitrary waveform generator and the coherent receiver, and obtain a first processed signal;

performing carrier frequency recovery processing and carrier phase recovery processing on the first processed signal to obtain a second processed signal;

Divide the second processed signal into two signals.

According to the symbol judgment method in optical fiber communication provided by the present invention, it also includes:

Based on the training sequence added to the optical signal, the length of the training sequence, and the optical signal, the noise variance of the two signals is determined.

The present invention also provides a symbol judgment device in optical fiber communication, including:

A first processing module, configured to receive an optical signal and a local carrier signal, and generate a quadrature modulation signal based on the optical signal and the local carrier signal;

a second processing module, configured to divide the quadrature modulation signal into two signals;

A loss determination module, configured to determine a symbol decision loss function based on the partial response filter, the noise variance of the two-way signals, and the probability value of the corresponding symbol of the two-way signals;

The decision module is configured to process the two-way signals based on the sign decision loss function, and obtain sign decision results of the two-way signals.

The present invention also provides an electronic device, including a memory, a processor, and a computer program stored on the memory and operable on the processor. The steps of the symbol decision method.

The present invention also provides a non-transitory computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the steps of any one of the above-mentioned symbol decision methods in optical fiber communication are realized.

The present invention also provides a computer program product, including a computer program. When the computer program is executed by a processor, the steps of any one of the above-mentioned symbol decision methods in optical fiber communication are implemented.

The symbol judgment method, device, electronic equipment, and storage medium in optical fiber communication provided by the present invention determine the symbol judgment through the partial response filter, the noise variance of the two-way signals, and the probability value of the corresponding symbol of the two-way signals The loss function is to process the two-way signals through the symbol decision loss function, so as to adjust the decision boundary of the symbol, so as to avoid the two-way decision boundary caused by the different distribution probabilities of each constellation point in the probability shaping signal. The impact of side signal probability changes to solve the defect of wrong judgment of symbols at multiple signal points in the prior art, and improve the accuracy of symbol judgment in optical fiber communication.

Description of drawings

In order to more clearly illustrate the present invention or the technical solutions in the prior art, the accompanying drawings that need to be used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the accompanying drawings in the following description are the present invention. For some embodiments of the invention, those skilled in the art can also obtain other drawings based on these drawings without creative effort.

Fig. 1 is a schematic flow chart of a symbol judgment method in optical fiber communication provided by the present invention;

Fig. 2 is a schematic diagram of the difference between the traditional symbol judgment provided by the present invention and the symbol judgment provided by the present invention;

3 is a schematic diagram of a signal transmission system corresponding to a symbol decision method in optical fiber communication provided by the present invention;

Fig. 4 is a schematic diagram of the frequency-amplitude response of the partial response filter provided by the present invention;

Fig. 5 is the corresponding relationship diagram of optical signal-to-noise ratio and bit error rate provided by the present invention;

Fig. 6 is a corresponding relationship diagram between signal transmission power and bit error rate provided by the present invention;

Fig. 7 is a corresponding relationship diagram between signal transmission power and normalized generalized mutual information provided by the present invention;

Fig. 8 is a schematic structural diagram of a symbol judgment device in optical fiber communication provided by the present invention;

FIG. 9 is a schematic structural diagram of an electronic device provided by the present invention.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions in the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the present invention. Obviously, the described embodiments are part of the embodiments of the present invention , but not all examples. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

The symbol decision method, device, electronic equipment and storage medium in optical fiber communication of the present invention will be described below with reference to FIGS. 1-9 .

As shown in Figure 1, the symbol decision method in the optical fiber communication provided by the present invention includes:

Step 110: Receive an optical signal and a local carrier signal, and generate a quadrature modulation signal based on the optical signal and the local carrier signal.

It can be understood that the optical signal can be obtained through the following steps:

The pseudo-random code module generates the data bit sequence required by the user for subsequent processing;

The probability shaping mapping module generates symbol data subject to a specific probability distribution according to the data bit sequence generated by the pseudo-random code module, and provides symbol data for modulation mapping;

The modulation mapping module generates a coherent communication system signal, that is, a square wave signal, based on the symbol data output by the probability shaping mapping module;

The root cosine shaping module performs root cosine shaping on the square wave signal generated by the modulation mapping module and then outputs a digital signal in the electrical domain, thereby improving the anti-interference characteristics of the square wave signal;

The arbitrary waveform generator will generate the signal output by the cosine shaping module, complete the conversion of the digital signal in the electrical domain to the analog signal in the electrical domain, and output the analog signal in the electrical domain;

The electrical amplifier performs voltage linear amplification on the analog signal in the electrical domain and then outputs it;

The externally tuned laser generates an optical carrier signal of a specific frequency;

The modulator modulates the amplified electrical domain analog signal output by the electrical amplifier onto the optical carrier signal to realize electro-optic modulation, and outputs the initial optical signal;

The first erbium-doped fiber amplifier amplifies the initial optical signal to obtain a first amplified optical signal;

The adjustable attenuator works together with the first erbium-doped fiber amplifier at the front end to control the input fiber power of the first amplified optical signal;

The optical fiber loop is the actual link for optical signal transmission, and is used for the transmission of the first amplified optical signal;

The second erbium-doped optical fiber amplifier: amplifies the power of the transmitted first amplified optical signal to obtain a second amplified optical signal, so that the second amplified optical signal meets the power requirement of the receiving end;

The optical bandpass filter filters the out-of-band noise introduced by the front-end amplifiers (namely: the first Erbium-doped fiber amplifier and the second Erbium-doped fiber amplifier) in the second amplified optical signal, and obtains the optical signal in step 110 and outputs it.

The local carrier signal is obtained based on a local oscillator laser, which is a local optical carrier generating device at the receiving end and provides a local carrier for the coherent receiver.

Coherent receiver: According to the coherent receiving system, complete the coherent receiving of optical signals and local carrier signals.

Further, based on the local carrier signal, coherent detection is performed on the optical signal output by the optical bandpass filter, and the carried signal is recovered, that is, the quadrature modulation signal.

Step 120, divide the quadrature modulation signal into two signals.

It can be understood that the optical signal output by the optical bandpass filter is a signal in the form of a complex signal, such as a signal in the form of a+bi, where a and b are two signals corresponding to the quadrature modulation signal, a is an I signal, b is the Q channel signal.

Step 130: Determine a symbol decision loss function based on a partial-response filter (partial-response filter), noise variance of the two signals, and probability values of symbols corresponding to the two signals.

It can be understood that, in the existing symbol decision methods, whether it is a uniformly distributed signal (UD Signal) or a probabilistic shaping signal (PS Signal), the decision boundary will be at V _UD as shown in Figure 2, resulting in a value between V _PS The signal between V _UD and V UD is misjudged a lot, which introduces a large performance loss. Therefore, for the probability shaping signal, its optimal decision function level should be at V _PS . In order to realize this condition, the loss function when performing symbol decision needs to be redefined based on the partial response filter, the noise variance of the two signals, and the probability values of the symbols corresponding to the two signals.

Figure 2 shows the difference between the new decision technique for probabilistically shaped signals and the traditional decision technique. V _PS indicates the decision boundary corresponding to the symbol decision technology in optical fiber communication, and V _UD indicates the decision boundary of traditional symbol decision. It can be seen that the decision boundaries of the two symbols are obviously different. The reason for the deviation is that the distribution probability of each constellation point in the probability shaping signal (PS Signal) is different, and the decision boundary will be affected by the change of the signal probability on both sides. When the probability of symbols is equal (UD Signal), the decision boundary (V _UD ) is the mean value of two adjacent symbols.

The present invention provides a signal transmission system as shown in FIG. 3 , that is, a 64-GBaud PS-16QAM platform. The digital signal processing algorithm at the transmitter is as follows: the 14th-order pseudo-random code is used as the signal source, and the quadrature and in-phase branches are respectively used for probability shaping mapping and root-raised cosine shaping. The generated PS-16QAM signal is sent to the arbitrary waveform generator, and after passing through a pair of 70-GHz electrical bandwidth drivers, the amplified RF signal is then loaded into a central wavelength by a single-biased IQ Mach-Zende modulator On the 1550.14nm optical carrier, the bias voltage of the modulator is set to zero. The synthesized signal is sent into the optical fiber through the attenuator and the first erbium-doped fiber amplifier. After being transmitted over multiple transmission distances, it is sent to an 80GSa/s sampling signal after passing through the second erbium-doped fiber amplifier and optical band-pass filter. Rate, 32-GHz bandwidth digital real-time oscilloscope to receive, and do subsequent digital signal processing on MATLAB software.

Step 140 , based on the sign decision loss function, process the two signals to obtain sign decision results of the two signals.

It is understandable that when performing symbol judgment, the above two signals need to be modulated and demapped first. When demapping, it is necessary to improve the existing Euclidean distance calculation scheme, optimize the symbol decision boundary, and obtain a demapping output with excellent performance. .

In some embodiments, the symbol decision method in optical fiber communication further includes:

Traverse the preset range of tap coefficients, and determine the tap coefficients with the lowest bit error rate of the symbol decision result as optimized coefficients;

Based on the optimized coefficients, the partial response filter is optimized.

It can be understood that, according to the comparison between the bit sequence generated after modulation and demodulation and the bit sequence before modulation and mapping, the number of error bits N is counted, and the total number of bits M output after modulation and demodulation is calculated to obtain the bit error rate E =N/M; Wherein, the process of step 110 to step 140 is the process of modulation and demodulation mapping.

Partial response filter _HPF is an important auxiliary technology to realize modulation and demodulation mapping, and its Z-domain expression can be expressed as:

H _PF (z)＝1+αz ^-1

In this expression, the only factor that affects the technical characteristics of _HPF is the tap coefficient α. Different α will make the 3-dB bandwidth of _HPF different. Refer to Figure 4 for details.

It can be seen that under different tap coefficients α, the amplitude-frequency response of HP _PF will be significantly different. As the tap coefficient α increases, the amplitude-frequency response of HP _PF becomes steeper, which also means that HP _PF The in-band noise of the signal can be compressed more effectively, but a larger α will also introduce greater inter-symbol crosstalk while suppressing the in-band noise, thereby deteriorating the performance of the signal. Therefore, there is a trade-off between α and performance. Therefore, we will traverse the tap coefficients with a step size of 0.1 within the range of the preset tap coefficients [0,1] to find the lowest bit error rate The optimization coefficients, and then realize the optimal design of the partial response filter.

The probability of a candidate sequence (candidate symbol or candidate sequence) is provided according to the probability distribution of symbols formed after modulation mapping.

Determine the survival sequence (survival sequence) X=(X ₁ , X ₂ , . . . , Xi, . . . X _k ):

In the process of signal modulation and demodulation, in the signal transmission system provided by the present invention, each Xi(i∈[1,k]) has 4 possible values, that is, Xi∈{-3,-1, 1, 3}(i∈[1,k]), so there will be 4 ^k different combinations in the process of signal modulation and demodulation, which can be generated according to the dictionary order in mathematics, so there will be 4 ^k kinds of metrics value AM, and the modulation/demapping scheme proposed by the present invention will output the corresponding arrangement according to the minimum AM value, that is, according to the minimum AM value, determine the bit sequence corresponding to the output surviving sequence from the candidate sequence, that is, The result of the symbol judgment of the above-mentioned two-way signals is that the modulation and demodulation mapping is completed.

In some embodiments, the determination of the symbol decision loss function based on the partial response filter, the noise variance of the two signals, and the probability value of the corresponding symbol of the two signals includes:

The sign decision loss function is determined based on the following formula:

Among them, AM is the cumulative metric value corresponding to the symbol decision loss function, which is used to select the best symbol sequence; DM _k is the loss function based on Euclidean distance, OM _k is the correction item added in the loss function, and Y _k is the two-way The symbol corresponding to the signal, _HPF is the partial response filter, X is the candidate sequence, σ ² is the noise variance of the two signals, and p(X _k ) is the probability of the symbol decision result X _k .

In some embodiments, the processing of the two-way signals based on the sign decision loss function to obtain sign decision results of the two-way signals includes:

Based on the symbol decision loss function, determine the bit sequence corresponding to the minimum cumulative metric value among the two signals, which is the decision result of the two signals.

It can be understood that, according to the loss function, finding a series of sequences X=(X ₁ , X ₂ , . . . X _k ) to minimize the AM value can obtain the modulation and demodulation scheme under the optimal decision.

In some embodiments, the dividing the quadrature modulation signal into two signals includes:

Perform clock signal recovery and equalization processing on the quadrature modulation signal, eliminate the clock frequency difference between the quadrature modulation signal corresponding to the arbitrary waveform generator and the coherent receiver, and obtain a first processed signal;

performing carrier frequency recovery processing and carrier phase recovery processing on the first processed signal to obtain a second processed signal;

Divide the second processed signal into two signals.

It can be understood that the steps of this embodiment can refer to Figure 2, as shown in Figure 2, clock recovery and equalization: complete the clock signal recovery of the signal, eliminate the clock frequency difference between the arbitrary waveform generator and the coherent receiver, and improve Signal quality, while the equalization technology can compensate for inter-symbol crosstalk and linear impairment in the link, and improve signal quality.

Carrier frequency recovery: Eliminate carrier frequency drift caused by the fixed frequency difference between the local oscillator laser and the externally tuned laser.

Carrier Phase Recovery: Eliminates phase noise in externally tuned lasers.

Modulation and Demapping: According to the scheme of the present invention, demapping of signals is performed.

In some embodiments, the symbol decision method in optical fiber communication further includes:

Based on the training sequence added to the optical signal, the length of the training sequence, and the optical signal, the noise variance of the two signals is determined.

It can be understood that the noise variance of the two signals can be estimated by adding a training sequence, that is, at the beginning of sending the optical signal corresponding to the two signals, we send a training sequence T _t of length L _t , then the noise variance can be estimated as:

Among them, _rt is the optical signal received from the channel, T _t is the training sequence, and L _t is the length of the training sequence.

In some embodiments, the symbol decision method in optical fiber communication provided by the present invention further includes:

Bit error rate statistics: compare the bit sequence generated after modulation and demodulation with the bit sequence before modulation and mapping, count the number of erroneous bits N, and calculate it with the total number of bits M output after modulation and demodulation to obtain a bit error Rate E=N/M.

In the symbol judgment method in optical fiber communication provided by the present invention, the relationship between the corresponding optical signal-to-noise ratio and the bit error rate is shown in Figure 5, and the line 1 in Figure 5 is the basic The relationship between OSNR and BER corresponding to the symbol decision method provided by the invention, line 2 in Fig. 5 shows the relationship between OSNR and BER corresponding to the existing symbol decision method. After 3200 kilometers of standard single-mode fiber transmission, the relationship between different transmit powers (optical signal power entering the fiber loop) and bit error rate and normalized generalized mutual information are shown in Figures 6 and 7, respectively.

Line 1 in Figure 6 shows the relationship between the transmit power and the bit error rate corresponding to the symbol decision method provided by the present invention, and line 2 in Figure 6 shows the relationship between the transmit power and the bit error rate corresponding to the existing symbol decision method .

Line 1 in Figure 7 shows the relationship between the transmit power corresponding to the symbol decision method provided by the present invention and the normalized generalized mutual information, and line 2 in Figure 7 shows the relationship between the transmit power and the normalized generalized mutual information corresponding to the existing symbol decision method generalized mutual information relationship.

In summary, the symbol decision method in optical fiber communication provided by the present invention includes: receiving an optical signal and a local carrier signal, and generating an orthogonal modulation signal based on the optical signal and the local carrier signal; The intermodulated signal is divided into two signals; based on the partial response filter, the noise variance of the two signals, and the probability value of the corresponding symbol of the two signals, a symbol decision loss function is determined; based on the symbol decision loss function, the The two-way signals are processed to obtain a sign judgment result of the two-way signals.

In the symbol decision method in optical fiber communication provided by the present invention, the symbol decision loss function is determined based on the partial response filter, the noise variance of the two-way signals, and the probability value of the corresponding symbol of the two-way signals, through the The symbol decision loss function, which processes the two-way signals, can adjust the decision boundary of the symbol to avoid the decision boundary being affected by the probability change of the signals on both sides because the distribution probability of each constellation point in the probability shaping signal is not the same. , so as to solve the defect of erroneous judgment of symbols of multiple signal points in the prior art, and improve the accuracy of symbol judgment in optical fiber communication.

The symbol judging device in the optical fiber communication provided by the present invention is described below, and the symbol judging device in the optical fiber communication described below and the symbol judging method in the optical fiber communication described above can refer to each other correspondingly.

As shown in FIG. 8 , the symbol decision device 800 in optical fiber communication provided by the present invention includes: a first processing module, a second processing module, a loss determination module and a decision module.

The first processing module is configured to receive an optical signal and a local carrier signal, and generate a quadrature modulation signal based on the optical signal and the local carrier signal.

The second processing module is used for dividing the quadrature modulation signal into two signals.

The loss determination module is configured to determine a symbol decision loss function based on the partial response filter, the noise variance of the two signals, and the probability value of the symbol corresponding to the two signals.

The judging module is configured to process the two signals based on the symbol decision loss function to obtain symbol judgment results of the two signals.

In some embodiments, the symbol decision device 800 in optical fiber communication further includes: an optimization parameter determination module and a filter determination module.

The optimization parameter determination module is used for traversing the preset range of tap coefficients, and determining the tap coefficient with the lowest bit error rate of the symbol decision result as the optimization coefficient.

The filter determination module is used for optimizing the partial response filter based on the optimization coefficient.

In some embodiments, the loss determination module is further configured to determine a symbol decision loss function based on the following formula:

Among them, AM is the cumulative metric value corresponding to the symbol decision loss function, which is used to select the best symbol sequence; DM _k is the loss function based on Euclidean distance, OM _k is the correction item added in the loss function, and Y _k is the two-way The symbol corresponding to the signal, _HPF is the partial response filter, X is the candidate sequence, σ ² is the noise variance of the two signals, and p(X _k ) is the probability of the symbol decision result X _k .

In some embodiments, the decision module is further configured to determine, based on the symbol decision loss function, the bit sequence corresponding to the minimum cumulative metric value among the two signals, as the decision result of the two signals.

In some embodiments, the second processing module includes: a first signal processing unit, a second signal processing unit and a decomposition unit.

The first signal processing unit is used to perform clock signal recovery and equalization processing on the quadrature modulation signal, eliminate the clock frequency difference between the quadrature modulation signal corresponding to the arbitrary waveform generator and the coherent receiver, and obtain the first processed signal .

The second signal processing unit is configured to perform carrier frequency recovery processing and carrier phase recovery processing on the first processed signal to obtain a second processed signal.

The decomposing unit is used to divide the second processed signal into two signals.

In some embodiments, the symbol decision device 800 in optical fiber communication further includes: a noise variance determination module.

The noise variance determination module is configured to determine the noise variance of the two signals based on the training sequence added to the optical signal, the length of the training sequence, and the optical signal.

The electronic device, computer program product and storage medium provided by the present invention are described below, and the electronic device, computer program product and storage medium described below and the symbol judgment method in optical fiber communication described above can be referred to in correspondence.

FIG. 9 illustrates a schematic diagram of the physical structure of an electronic device. As shown in FIG. 9, the electronic device may include: a processor (processor) 910, a communication interface (Communications Interface) 920, a memory (memory) 930, and a communication bus 940, Wherein, the processor 910 , the communication interface 920 , and the memory 930 communicate with each other through the communication bus 940 . The processor 910 can call the logic instructions in the memory 930 to execute the symbol decision method in optical fiber communication, and the method includes:

Step 110, receiving an optical signal and a local carrier signal, and generating a quadrature modulation signal based on the optical signal and the local carrier signal;

Step 120, dividing the quadrature modulation signal into two signals;

Step 130, based on the partial response filter, the noise variance of the two signals, and the probability values of the symbols corresponding to the two signals, determine a symbol decision loss function;

Step 140 , based on the sign decision loss function, process the two signals to obtain sign decision results of the two signals.

In addition, the above-mentioned logic instructions in the memory 930 may be implemented in the form of software function units and may be stored in a computer-readable storage medium when sold or used as an independent product. Based on this understanding, the essence of the technical solution of the present invention or the part that contributes to the prior art or the part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including Several instructions are used to make a computer device (which may be a personal computer, a server, or a network device, etc.) execute all or part of the steps of the methods described in various embodiments of the present invention. The aforementioned storage medium includes: 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. .

On the other hand, the present invention also provides a computer program product. The computer program product includes a computer program that can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can Performing the symbol judgment method in optical fiber communication provided by each of the above methods, the method includes:

Step 110, receiving an optical signal and a local carrier signal, and generating a quadrature modulation signal based on the optical signal and the local carrier signal;

Step 120, dividing the quadrature modulation signal into two signals;

Step 130, based on the partial response filter, the noise variance of the two signals, and the probability values of the symbols corresponding to the two signals, determine a symbol decision loss function;

Step 140 , based on the sign decision loss function, process the two signals to obtain sign decision results of the two signals.

In another aspect, the present invention also provides a non-transitory computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, it is implemented to perform the symbol judgment method in optical fiber communication provided by the above methods, The method includes:

Step 110, receiving an optical signal and a local carrier signal, and generating a quadrature modulation signal based on the optical signal and the local carrier signal;

Step 120, dividing the quadrature modulation signal into two signals;

Step 130, based on the partial response filter, the noise variance of the two signals, and the probability values of the symbols corresponding to the two signals, determine a symbol decision loss function;

Step 140 , based on the sign decision loss function, process the two signals to obtain sign decision results of the two signals.

The device embodiments described above are only illustrative, and the units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in One place, or it can be distributed to multiple network elements. Part or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment. It can be understood and implemented by those skilled in the art without any creative effort.

Through the above description of the implementations, those skilled in the art can clearly understand that each implementation can be implemented by means of software plus a necessary general-purpose hardware platform, and of course also by hardware. Based on this understanding, the essence of the above technical solution or the part that contributes to the prior art can be embodied in the form of software products, and the computer software products can be stored in computer-readable storage media, such as ROM/RAM, magnetic discs, optical discs, etc., including several instructions to make a computer device (which may be a personal computer, server, or network device, etc.) execute the methods described in various embodiments or some parts of the embodiments.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: it can still be Modifications are made to the technical solutions described in the foregoing embodiments, or equivalent replacements are made to some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims (8)

1. a symbol judgment method in optical fiber communication, it is characterized in that, comprising: receiving an optical signal and a local carrier signal, and generating a quadrature modulation signal based on the optical signal and the local carrier signal; dividing the quadrature modulation signal into two signals; Based on the partial response filter, the noise variance of the two-way signals, and the probability value of the corresponding symbol of the two-way signals, determine a symbol decision loss function; Processing the two-way signals based on the sign decision loss function to obtain sign decision results of the two-way signals; The determination of a symbol decision loss function based on the partial response filter, the noise variance of the two-way signals, and the probability value of the corresponding symbol of the two-way signals includes: The sign decision loss function is determined based on the following formula: Among them, AM is the cumulative metric value corresponding to the symbol decision loss function, which is used to select the best symbol sequence; Y _k is the symbol corresponding to the two signals, HP _PF is the partial response filter, X is the candidate sequence, σ ² is the two The noise variance of the channel signal, p(X _k ) is the probability of the symbol decision result X _k . 2. the symbol judgment method in the optical fiber communication according to claim 1, is characterized in that, also comprises: Traverse the preset range of tap coefficients, and determine the tap coefficients with the lowest bit error rate of the symbol decision result as optimized coefficients; Based on the optimized coefficients, the partial response filter is optimized. 3. the symbol decision method in the optical fiber communication according to claim 1, is characterized in that, described based on described symbol decision loss function, described two-way signal is processed, obtains the sign decision result of described two-way signal ,include: Based on the symbol decision loss function, determine the bit sequence corresponding to the minimum cumulative metric value among the two signals, which is the decision result of the two signals. 4. the symbol judgment method in the optical fiber communication according to claim 1, is characterized in that, described quadrature modulation signal is divided into two-way signal, comprises: Perform clock signal recovery and equalization processing on the quadrature modulation signal, eliminate the clock frequency difference between the quadrature modulation signal corresponding to the arbitrary waveform generator and the coherent receiver, and obtain a first processed signal; performing carrier frequency recovery processing and carrier phase recovery processing on the first processed signal to obtain a second processed signal; Divide the second processed signal into two signals. 5. The symbol decision method in the optical fiber communication according to any one of claims 1-4, is characterized in that, also comprises: Based on the training sequence added to the optical signal, the length of the training sequence, and the optical signal, the noise variance of the two signals is determined. 6. A symbol decision device in optical fiber communication, characterized in that, comprising: A first processing module, configured to receive an optical signal and a local carrier signal, and generate a quadrature modulation signal based on the optical signal and the local carrier signal; a second processing module, configured to divide the quadrature modulation signal into two signals; A loss determination module, configured to determine a symbol decision loss function based on the partial response filter, the noise variance of the two-way signals, and the probability value of the corresponding symbol of the two-way signals; A decision module, configured to process the two-way signals based on the sign decision loss function, to obtain sign decision results of the two-way signals; The loss determination module is specifically used for: The sign decision loss function is determined based on the following formula: Among them, AM is the cumulative metric value corresponding to the symbol decision loss function, which is used to select the best symbol sequence; Y _k is the symbol corresponding to the two signals, HP _PF is the partial response filter, X is the candidate sequence, σ ² is the two The noise variance of the channel signal, p(X _k ) is the probability of the symbol decision result X _k . 7. An electronic device comprising a memory, a processor, and a computer program stored on the memory and operable on the processor, wherein the processor according to claim 1 is implemented when executing the program. The steps of the symbol decision method in optical fiber communication described in any one of 5 to 5. 8. A non-transitory computer-readable storage medium, on which a computer program is stored, characterized in that, when the computer program is executed by a processor, the symbol in the optical fiber communication according to any one of claims 1 to 5 is realized Steps in the Judgment Method.