Method and device for obtaining coding rate of quantum key distribution device

Abstract

The method and device for obtaining the coding rate of a quantum key distribution device provided in the present application belong to the field of quantum communication technology. The method and device use a one-dimensional Brownian motion process to model the quantum state polarization drift phenomenon, and model the self-startup, self-checking and restart processes of the quantum key distribution device, thereby quantitatively measuring the influence of noise interference and device startup factors on the coding rate, and more accurately obtaining the coding rate of the quantum key distribution device in actual engineering.

Description

Technical Field

[0001] The present application belongs to the field of quantum communication technology, and in particular, relates to a method and device for obtaining the coding rate of a quantum key distribution device. Background Art

[0002] Quantum key distribution (QKD) is a technology that uses the indivisible, unclonable and immeasurable physical properties of light quanta to distribute keys and thus ensure communication security.

[0003] However, in the existing technology, only the theoretical coding rate is often considered. In actual engineering, due to external interference, such as the influence of curvature and temperature, the polarization of the quantum state will become chaotic when transmitted in the optical fiber, resulting in a decrease in fidelity and thus affecting the coding rate. On the other hand, QKD self-checking and self-starting processes will also consume time and reduce the coding rate. If AI algorithms such as neural networks lack effective physical meaning analysis, it is difficult to ensure the transferability of the calculation method. Although the analytical method has a clear physical meaning, there is currently a lack of effective methods to model the unstable factors of QKD equipment in the actual operating environment, making it difficult to effectively calculate and simulate the coding rate in actual engineering. Summary of the invention

[0004] The present application provides a method and apparatus for obtaining a coding rate of a quantum key distribution device.

[0005] Some embodiments of the present application provide a method for obtaining a coding rate of a quantum key distribution device, the method comprising:

[0006] Simulating the startup process of a quantum key device to initialize the key quantity, coding time and polarization modulation deviation angle of the quantum key device;

[0007] When the current time is less than the preset coding statistical time, the polarization drift in the optical fiber is modeled using a one-dimensional Brownian motion model, the polarization deviation angle is simulated and calculated in real time, and then the signal state error rate of the key distribution device is obtained based on the polarization modulation deviation angle, and the self-test process of the key distribution device is simulated;

[0008] When the signal state error rate is greater than or equal to the error rate threshold, simulating a restart process of the quantum key device, initializing the polarization modulation deviation angle, and adjusting the coding time using the time of the restart process;

[0009] When the signal state error rate is less than the error rate threshold, the coding time is accumulated, the polarization modulation deviation angle is adjusted based on the normal distribution parameter, the key amount is accumulated based on the polarization modulation deviation angle, and it is re-determined whether the current time is less than the preset coding statistical time;

[0010] When the current time is greater than or equal to the preset coding statistical time, the coding rate of the quantum key distribution device is calculated based on the key amount and the coding time.

[0011] Optionally, acquiring the signal state error rate of the key distribution device based on the polarization modulation deviation angle includes:

[0012] Modeling the polarization modulation deviation angle drift based on a one-dimensional Brownian motion model, wherein the polarization modulation deviation angle obtains the optical error rate of the key distribution device at the current moment;

[0013] The upper limit of the signal state error rate of the key distribution device at the current moment is obtained based on the optical error rate.

[0014] Optionally, the obtaining, based on the optical error rate, an upper limit of a signal state error rate of the key distribution device at a current moment includes:

[0015] Obtain the dark count rate of single photon detector based on the intrinsic dark count of single photon detector and the noise count introduced by Raman noise;

[0016] The signal state gain probability is obtained based on the dark count rate of the single-photon detector, the average number of photons in a single pulse of the signal state, the attenuation coefficient of quantum light in the optical fiber, the length of the optical fiber, the detection efficiency of the single-photon detector, and the losses other than the optical fiber loss;

[0017] Obtaining a lower limit value of the signal state gain probability according to the signal state gain probability, the number of signal state pulses, and the confidence level;

[0018] Based on the signal state optical error rate, vacuum state error rate, single photon detector dark count rate, signal state single pulse average photon number, quantum light attenuation coefficient in optical fiber, optical fiber length, single photon detector detection efficiency, and other losses except optical fiber loss, obtain the product of signal state measurement error rate and signal state gain probability;

[0019] Based on the product of the signal state measurement error rate and the signal state gain probability, the number of signal state pulses, and the confidence level, obtaining an upper limit value of the product of the signal state measurement error rate and the signal state gain probability;

[0020] Based on the upper limit value of the product of the signal state measurement error rate and the signal state gain probability and the lower limit value of the signal state gain probability, the upper limit value of the signal state error rate at the current moment is obtained.

[0021] Optionally, the accumulating the key amount based on the polarization modulation deviation angle includes:

[0022] Calculating the amount of coding per unit time based on the polarization modulation deviation angle;

[0023] The amount of passwords is accumulated using the amount of codes generated in the unit time.

[0024] Optionally, the calculating the amount of coding per unit time based on the polarization modulation deviation angle includes:

[0025] Based on the polarization modulation deviation angle, an upper limit value of a signal state single photon pulse error rate and a lower limit value of a signal state single photon pulse response rate under Raman noise are obtained;

[0026] Based on the upper limit value of the signal state single-photon pulse error rate and the lower limit value of the signal state single-photon pulse response rate, the amount of coding per unit time is obtained.

[0027] Optionally, the obtaining, based on the polarization modulation deviation angle, an upper limit value of a signal state single photon pulse error rate and a lower limit value of a signal state single photon pulse response rate under Raman noise includes:

[0028] Based on the polarization modulation deviation angle, obtaining an optical error rate;

[0029] Acquire a signal state gain probability and a decoy state gain probability based on the optical error rate;

[0030] Obtaining a lower limit of the decoy state gain probability based on the decoy state gain probability, the number of decoy state pulses, and the confidence level;

[0031] Obtaining an upper limit of the signal state gain probability based on the signal state gain probability, the number of signal state pulses, and the confidence level;

[0032] Obtain the lower and upper limits of the dark count rate of the single-photon detector based on the dark count rate of the single-photon detector, the number of vacuum pulses, and the confidence level;

[0033] Based on the number of signal state pulses, the number of decoy state pulses, the confidence level, the vacuum state measurement error rate, the optical error rate, the dark count rate of the single-photon detector, the average number of photons in the signal state pulses, the average number of photons in the decoy state pulses, the attenuation coefficient of quantum light in the optical fiber, the optical fiber length, the detection efficiency of the single-photon detector, and the losses other than the optical fiber loss, the upper limit of the product of the signal state error rate and the gain probability and the upper limit of the product of the decoy state error rate and the gain probability are obtained;

[0034] Based on the lower limit of the decoy state gain probability, the upper limit of the signal state gain probability, the upper and lower limits of the dark count rate of the single-photon detector, the upper limit of the product of the signal state error rate and gain probability, the upper limit of the product of the decoy state error rate and gain probability, the vacuum state measurement error rate, the average photon number of the signal state pulse, and the average photon number of the decoy state pulse, the upper limit of the signal state single-photon pulse error rate and the lower limit of the signal state single-photon pulse response rate under Raman noise are obtained.

[0035] Some embodiments of the present application provide a device for obtaining a coding rate of a quantum key distribution device, the device comprising:

[0036] A simulation module, used to simulate the startup process of a quantum key device, and initialize the key quantity, coding time and polarization modulation deviation angle of the quantum key device;

[0037] When the current time is less than the preset coding statistical time, the polarization drift in the optical fiber is modeled using a one-dimensional Brownian motion model, the polarization deviation angle is simulated and calculated in real time, and then the signal state error rate of the key distribution device is obtained based on the polarization modulation deviation angle, and the self-test process of the key distribution device is simulated;

[0038] When the signal state error rate is greater than or equal to the error rate threshold, simulating a restart process of the quantum key device, initializing the polarization modulation deviation angle, and adjusting the coding time using the time of the restart process;

[0039] When the signal state error rate is less than the error rate threshold, the coding time is accumulated, the polarization modulation deviation angle is adjusted based on the normal distribution parameter, the key amount is accumulated based on the polarization modulation deviation angle, and it is re-determined whether the current time is less than the preset coding statistical time;

[0040] The processing module is used to calculate the coding rate of the quantum key distribution device based on the key amount and the coding time when the current time is greater than or equal to the preset coding statistical time.

[0041] Optionally, the simulation module is further used for:

[0042] Modeling the polarization modulation deviation angle drift based on a one-dimensional Brownian motion model, wherein the polarization modulation deviation angle obtains the optical error rate of the key distribution device at the current moment;

[0043] The upper limit of the signal state error rate of the key distribution device at the current moment is obtained based on the optical error rate.

[0044] Optionally, the simulation module is further used for:

[0045] Obtain the dark count rate of single photon detector based on the intrinsic dark count of single photon detector and the noise count introduced by Raman noise;

[0046] The signal state gain probability is obtained based on the dark count rate of the single-photon detector, the average number of photons in a single pulse of the signal state, the attenuation coefficient of quantum light in the optical fiber, the length of the optical fiber, the detection efficiency of the single-photon detector, and the losses other than the optical fiber loss;

[0047] Obtaining a lower limit value of the signal state gain probability according to the signal state gain probability, the number of signal state pulses, and the confidence level;

[0048] Based on the signal state optical error rate, vacuum state error rate, single photon detector dark count rate, signal state single pulse average photon number, quantum light attenuation coefficient in optical fiber, optical fiber length, single photon detector detection efficiency, and other losses except optical fiber loss, obtain the product of signal state measurement error rate and signal state gain probability;

[0049] Based on the product of the signal state measurement error rate and the signal state gain probability, the number of signal state pulses, and the confidence level, obtaining an upper limit value of the product of the signal state measurement error rate and the signal state gain probability;

[0050] Based on the upper limit value of the product of the signal state measurement error rate and the signal state gain probability and the lower limit value of the signal state gain probability, the upper limit value of the signal state error rate at the current moment is obtained.

[0051] Optionally, the simulation module is further used for:

[0052] Calculating the amount of coding per unit time based on the polarization modulation deviation angle;

[0053] The amount of passwords is accumulated using the amount of codes generated in the unit time.

[0054] Optionally, the simulation module is further used for:

[0055] Based on the polarization modulation deviation angle, an upper limit value of a signal state single photon pulse error rate and a lower limit value of a signal state single photon pulse response rate under Raman noise are obtained;

[0056] Based on the upper limit value of the signal state single-photon pulse error rate and the lower limit value of the signal state single-photon pulse response rate, the amount of coding per unit time is obtained.

[0057] Optionally, the simulation module is further used for:

[0058] Based on the polarization modulation deviation angle, obtaining an optical error rate;

[0059] Acquire a signal state gain probability and a decoy state gain probability based on the optical error rate;

[0060] Obtaining a lower limit of the decoy state gain probability based on the decoy state gain probability, the number of decoy state pulses, and the confidence level;

[0061] Obtaining an upper limit of the signal state gain probability based on the signal state gain probability, the number of signal state pulses, and the confidence level;

[0062] Obtain the lower and upper limits of the dark count rate of the single-photon detector based on the dark count rate of the single-photon detector, the number of vacuum pulses, and the confidence level;

[0063] Based on the number of signal state pulses, the number of decoy state pulses, the confidence level, the vacuum state measurement error rate, the optical error rate, the dark count rate of the single-photon detector, the average number of photons in the signal state pulses, the average number of photons in the decoy state pulses, the attenuation coefficient of quantum light in the optical fiber, the optical fiber length, the detection efficiency of the single-photon detector, and the losses other than the optical fiber loss, the upper limit of the product of the signal state error rate and the gain probability and the upper limit of the product of the decoy state error rate and the gain probability are obtained;

[0064] Based on the lower limit of the decoy state gain probability, the upper limit of the signal state gain probability, the upper and lower limits of the dark count rate of the single-photon detector, the upper limit of the product of the signal state error rate and gain probability, the upper limit of the product of the decoy state error rate and gain probability, the vacuum state measurement error rate, the average photon number of the signal state pulse, and the average photon number of the decoy state pulse, the upper limit of the signal state single-photon pulse error rate and the lower limit of the signal state single-photon pulse response rate under Raman noise are obtained.

[0065] Some embodiments of the present application provide a computing processing device, including:

[0066] a memory having computer readable code stored therein;

[0067] One or more processors. When the computer-readable code is executed by the one or more processors, the computing processing device executes the coding rate acquisition method of the quantum key distribution device as described above.

[0068] Some embodiments of the present application provide a computer program, including a computer-readable code, which, when executed on a computing and processing device, causes the computing and processing device to execute the coding rate acquisition method of the quantum key distribution device as described above.

[0069] Some embodiments of the present application provide a non-transitory computer-readable medium, in which a coding rate acquisition method of a quantum key distribution device as described above is stored.

[0070] The coding rate acquisition method and apparatus of a quantum key distribution device provided in some embodiments of the present application model the quantum state polarization drift phenomenon by utilizing a one-dimensional Brownian motion process, and model the self-startup, self-checking and restarting processes of the quantum key distribution device, thereby quantitatively measuring the influence of noise interference and device startup factors on the coding rate, and can more accurately acquire the coding rate of the quantum key distribution device in actual engineering.

[0071] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0072] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0073] Figure 1 A schematic diagram of a process for obtaining a coding rate of a quantum key distribution device provided in some embodiments of the present application is schematically shown;

[0074] Figure 2 The following schematically shows an architecture diagram of a quantum key distribution system provided by some embodiments of the present application;

[0075] Figure 3 A logical diagram of a method for obtaining a coding rate of a quantum key distribution device provided in some embodiments of the present application is schematically shown;

[0076] Figure 4 One of the effect schematic diagrams of a method for obtaining a coding rate of a quantum key distribution device provided in some embodiments of the present application is schematically shown;

[0077] Figure 5 The second schematic diagram schematically shows the effect of a method for obtaining a coding rate of a quantum key distribution device provided in some embodiments of the present application;

[0078] Figure 6 The structure diagram of a coding rate acquisition device of a quantum key distribution device provided in some embodiments of the present application is schematically shown;

[0079] Figure 7 The structural diagram of the exemplary device provided in some embodiments of the present application is schematically shown. DETAILED DESCRIPTION

[0080] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0081] Figure 1 A schematic diagram of a process flow of a method for obtaining a coding rate of a quantum key distribution device provided by the present application is schematically shown, and the method comprises:

[0082] Step 101, simulating the startup process of a quantum key device, initializing the key quantity, coding time and polarization modulation deviation angle of the quantum key device.

[0083] Step 102, when the current time is less than the preset coding statistical time, the polarization drift in the optical fiber is modeled using a one-dimensional Brownian motion model, the polarization deviation angle is calculated in real time, and then the signal state error rate of the key distribution device is obtained based on the polarization modulation deviation angle, and the self-test process of the key distribution device is simulated.

[0084] Step 103, when the signal state error rate is greater than or equal to the error rate threshold, simulate the restart process of the quantum key device, initialize the polarization modulation deviation angle, and use the time of the restart process to adjust the coding time.

[0085] Step 104, when the signal state error rate is less than the error rate threshold, the coding time is accumulated, the polarization modulation deviation angle is adjusted based on the normal distribution parameters, the key amount is accumulated based on the polarization modulation deviation angle, and it is re-determined whether the current time is less than the preset coding statistical time.

[0086] Step 105: When the current time is greater than or equal to the preset coding statistical time, the coding rate of the quantum key distribution device is calculated based on the key amount and the coding time.

[0087] It should be noted that quantum key distribution equipment is an electronic device used to implement quantum key distribution. Generally, quantum key distribution equipment includes but is not limited to: a transmitter and a receiver. In order to save optical fiber resources, it is often necessary to transmit quantum light and classical light on the same fiber. Generally, refer to Figure 2 The common fiber transmission equipment includes but is not limited to: a transmitting end, a receiving end, a wavelength division multiplexing module 1, a wavelength division multiplexing module 2, a bandpass filter module, an optical fiber box, and a classic optical transceiver.

[0088] Among them, the transmitting end and the receiving end together constitute a quantum key distribution system, which are respectively used to receive and send quantum keys; the wavelength division multiplexing module 1 and the wavelength division multiplexing module 2 are used to combine and split the quantum photosynthetic classical light respectively; the bandpass filter module is used to filter out the remaining noise except Raman noise to improve the performance of the quantum key distribution system; the optical fiber box is used to transmit quantum keys; and the classical optical transceiver is used to receive and send classical light.

[0089] In the embodiment of the present application, the startup process of the simulated quantum key distribution device is realized by using the Monte Carlo simulation method. The Monte Carlo simulation method is a numerical calculation method guided by probability statistics theory. It can use random numbers or more common pseudo-random numbers, and conduct sampling experiments or random simulations on the statistics of existing data of random variables to obtain a certain digital feature of the statistic and use it as the numerical solution to the problem to be solved. In the embodiment of the present application, the startup and self-check process of the quantum key device is simulated, and the parameters generated by the quantum key device during the startup and self-check process are simulated and counted, so as to calculate the coding rate of the quantum key distribution device under the influence of noise interference and coding rate deviation caused by self-check.

[0090] Specifically, the average coding rate of the quantum key distribution device in the optical fiber transmission system shared by classical light and quantum light within the preset coding statistical time T can be simulated and calculated. Figure 3 , which is calculated in the following way:

[0091] Step S1, firstly, initializes parameters such as coding time, key quantity and polarization modulation angle, so as to simulate the initial startup and self-calibration process of the quantum key distribution device.

[0092] Among them, the coding time t is initialized to T start , key quantity K sum Initialized to 0, the polarization modulation deviation angle θ is initialized to 0. It can be understood that after the quantum key distribution device is started, it has not yet run, so the amount of key sent is 0, and the device has just been started and polarization calibration has been performed, so there is no offset, and the polarization modulation deviation angle is also 0, and T start It refers to the time taken by the quantum key distribution device to start up, which can be calculated by the following formula (1):

[0093]

[0094] Here n noise The noise introduced by the environment is used to measure the fixed time, k and m are constants. If you want to simulate the average coding rate of the QKD device within the calculation time T.

[0095] Step S2, determining whether the current time t is less than the preset coding statistical time T.

[0096] If it is less than the preset coding statistical time T, then continue to execute step S3; if it is greater than or equal to the preset coding statistical time T, then proceed to execute step S6.

[0097] The preset coding statistical time here can be a system default setting or a user-set time. It can be set according to actual needs and is not limited here.

[0098] Step S3, simulating the process of the QKD device's timed self-test, according to the polarization modulation deviation angle θ at the current moment t Calculate the signal state error rate and determine whether the polarization modulation deviation angle is less than a given deviation angle threshold.

[0099] If the polarization modulation deviation angle is less than the deviation angle threshold, it means that the quantum key distribution device is operating normally, and step S4 is executed. If the polarization modulation deviation angle is greater than or equal to the deviation angle threshold, it means that the quantum key distribution device is operating normally, and step S5 is executed.

[0100] Step S4: Substitute the calculated parameters into the GLLP formula to calculate the coding rate per unit time, and update the accumulated key amount K sum =K sum +K, time t=t+1 and polarization modulation deviation angle θ t+1 =θ t +Δθ, where Δθ follows the normal distribution N(0,σ 2 ), and returns to step S2 to continue simulating the operation process of the quantum key distribution device.

[0101] Step S5, simulate the self-check failure process, at this time QKD needs to be restarted and calibrated, which takes time T start , update time t = t + T start And initialize the polarization modulation deviation angle θ = 0, and return to step S2.

[0102] Step S6, calculate the average encoding rate according to the accumulated key quantity and encoding time, and output the result.

[0103] In different environments or considering different equipment imperfections, the formulas for calculating the signal state error rate and the coding rate in steps S3 and S4 can be modified, and the remaining steps remain unchanged, which does not affect the validity of this patent.

[0104] For example, assuming that the fixed optical fiber length is 50 km, the optical power of the classic optical signal is changed, and the average bit rate test results within 30 minutes are as follows: Figure 4 and Figure 5 As shown, the hollow circles represent the measured data. Figure 4 The solid line in represents the result obtained by using the traditional method, that is, directly using the GLLP formula to calculate the bit rate without using Monte Carlo simulation. Figure 5 The solid line in is the result calculated by the method proposed in the embodiment of the present application. It can be found that the result calculated by the traditional method is quite different from the actual coding rate of the two-word key distribution device. The coding rate calculated by the Monte Carlo simulation method is well matched with the actual coding rate, and the curve of the result calculated by the traditional method is relatively smooth. The result calculated by the coding rate acquisition method of the quantum key distribution device provided in the embodiment of the present application is volatile, which is consistent with the measured data, reflecting the instability of the operation results of the quantum key distribution device in the actual environment.

[0105] The embodiment of the present application uses a one-dimensional Brownian motion process to model the quantum state polarization drift phenomenon, and models the self-startup, self-checking and restart processes of the quantum key distribution device, quantitatively measures the impact of noise interference and device startup factors on the coding rate, and can more accurately obtain the coding rate of the quantum key distribution device in actual engineering.

[0106] Optionally, the step 102 includes:

[0107] Step 1021: Modeling the polarization modulation deviation angle drift based on a one-dimensional Brownian motion model, where the polarization modulation deviation angle obtains the optical error rate of the key distribution device at the current moment.

[0108] Step 1022: Obtain an upper limit of a signal state error rate of the key distribution device at a current moment based on the optical error rate.

[0109] Optionally, the step 1022 includes:

[0110] Step 10221, obtaining a dark count rate of the single photon detector based on the intrinsic dark count of the single photon detector and the noise count introduced by Raman noise;

[0111] Step 10222, obtaining the signal state gain probability based on the dark count rate of the single-photon detector, the average number of photons in a single pulse of the signal state, the attenuation coefficient of quantum light in the optical fiber, the length of the optical fiber, the detection efficiency of the single-photon detector, and the remaining losses except the optical fiber loss;

[0112] Step 10223, obtaining a lower limit value of the signal state gain probability according to the signal state gain probability, the number of signal state pulses, and the confidence level;

[0113] Step 10224, based on the signal state optical error rate, vacuum state error rate, single photon detector dark count rate, signal state single pulse average photon number, quantum light attenuation coefficient in optical fiber, optical fiber length, single photon detector detection efficiency, and other losses except optical fiber loss, obtain the product of signal state measurement error rate and signal state gain probability;

[0114] Step 10225, obtaining an upper limit value of the product of the signal state measurement error rate and the signal state gain probability based on the product of the signal state measurement error rate and the signal state gain probability, the number of signal state pulses, and the confidence level;

[0115] Step 10226, based on the upper limit value of the product of the signal state measurement error rate and the signal state gain probability and the lower limit value of the signal state gain probability, obtain the upper limit value of the signal state error rate at the current moment.

[0116] In the embodiment of the present application, the number of Raman noise photons introduced by classical light can be calculated by referring to formulas (2), (3), and (4): ram :

[0117]

[0118] P ram =S(l)Δf filter τ gate f gate (3)

[0119]

[0120] Among them, P0 is the incident light intensity of classical light, β s is the spontaneous Raman scattering coefficient of classical light, α P and α s are the attenuation coefficients of classical light and quantum light in optical fibers, Δf filter is the bandwidth of the bandpass filter, τ gate is the single gate width of the single photon detector at the receiving end of quantum key distribution, f gate is the single photon detector gate repetition frequency, l is the fiber length, η det is the detection efficiency of the single-photon detector, α cou To remove the remaining losses except the fiber loss, λ raman is the wavelength of the Raman noise.

[0121] The process of calculating the signal state error rate is as follows:

[0122] Assuming that the repetition frequency of the quantum key distribution device is f, the total number of pulses sent by the transmitter within time T is N = fT, and the probabilities of sending the signal state, decoy state and vacuum state are p respectively. μ , p v, p0, then the number of signal states, decoy states and vacuum states sent during this period of time is as follows:

[0123] N μ =Np μ ,N ν =Np ν ,N0=Np0 (5)

[0124] The average single pulse photon numbers in the signal state, decoy state and vacuum state are: μ, ν, 0. The intrinsic dark count of the single photon detector in time T is n0, so the coding probability under Lyman noise in the co-fiber transmission system of classical light and quantum light is as follows (6):

[0125]

[0126] When the fiber length is l, the gain probability is as follows:

[0127]

[0128] Therefore, the number of signal states, decoy states and vacuum states received by the receiving end are respectively as follows (9):

[0129] M μ =N μ Q μ ,M ν =N ν Q ν ,M0=N0Y0 (9)

[0130] According to simple statistical fluctuation analysis, the following formula (10) can be obtained:

[0131]

[0132] Here, the superscripts L and U represent the lower and upper limits of the estimated parameters, respectively, and δ is the confidence level. μ ,E ν , e0 are the error rates measured in the signal state, decoy state and vacuum state respectively. Calculate e at time t opt,t As shown in the following formula (11):

[0133] e opt,t =e opt +(1-e opt )sin 2 θ t (11)

[0135] When the transmitter sends the vacuum state, the photons measured by the receiver are completely derived from the dark counts and Raman noise of the single-photon detector, so its polarization can be considered to be chaotic, and the error probability is e0 = 0.5. Similarly, when the QKD transmitter transmits the signal state and the decoy state, if the QKD receiver detects photons that do not come from the QKD transmitter, the error probability is the same as e0; otherwise, the error rate is e opt，t , so we can get the following formulas (12) and (13):

[0136]

[0137]

[0138] Similarly, the following formula (14) can be obtained based on statistical analysis:

[0139]

[0140] Substituting formula (10) and formula (14) into the following formula (15), the upper limit of the signal state error rate can be obtained:

[0141] (15)

[0142] Optionally, the step 104 includes:

[0143] Step 1041, calculating the amount of coding per unit time based on the polarization modulation deviation angle.

[0144] Step 1042: accumulating the password amount using the amount of code generated in the unit time.

[0145] Optionally, the step 1041 includes:

[0146] Step 10411, obtaining an upper limit value of a signal state single photon pulse error rate and a lower limit value of a signal state single photon pulse response rate under Raman noise based on the polarization modulation deviation angle;

[0147] Step 10412, based on the upper limit value of the signal state single-photon pulse error rate and the lower limit value of the signal state single-photon pulse response rate, obtain the coding amount per unit time.

[0148] Optionally, the step 10411 includes:

[0149] Step 104111, obtaining an optical error rate based on the polarization modulation deviation angle;

[0150] Step 104112, obtaining a signal state gain probability and a decoy state gain probability based on the optical error rate;

[0151] Step 104113, obtaining a lower limit of the decoy state gain probability based on the decoy state gain probability, the number of decoy state pulses, and the confidence level;

[0152] Step 104114, obtaining the upper limit of the signal state gain probability based on the signal state gain probability, the number of signal state pulses, and the confidence level;

[0153] Step 104115, obtaining a lower limit and an upper limit of a dark count rate of the single photon detector based on the dark count rate of the single photon detector, the number of vacuum state pulses, and the confidence level;

[0154] Step 104116, based on the number of signal state pulses, the number of decoy state pulses, the confidence level, the vacuum state measurement error rate, the optical error rate, the single-photon detector dark count rate, the average number of photons in the signal state pulses, the average number of photons in the decoy state pulses, the attenuation coefficient of quantum light in the optical fiber, the optical fiber length, the detection efficiency of the single-photon detector, and the losses other than the optical fiber loss, obtain the upper limit of the product of the signal state error rate and the gain probability, and the upper limit of the product of the decoy state error rate and the gain probability;

[0155] Step 104117, based on the lower limit of the spoofed state gain probability, the upper limit of the signal state gain probability, the upper and lower limits of the dark count rate of the single-photon detector, the upper limit of the product of the signal state error rate and gain probability, the upper limit of the product of the spoofed state error rate and gain probability, the vacuum state measurement error rate, the average number of photons in the signal state pulse, and the average number of photons in the spoofed state pulse, obtain the upper limit value of the signal state single-photon pulse error rate under Raman noise and the lower limit value of the signal state single-photon pulse response rate.

[0156] In the embodiment of the present application, the above formula (10) and formula (14) are substituted into the following formula (16) and formula (17):

[0157]

[0158] Then substitute the parameters calculated by the above formula into the GLLP formula shown in formula (18) and calculate the bit rate per unit time:

[0159]

[0160] It should be noted that, for the method embodiments, for the sake of simplicity, they are all expressed as a series of action combinations, but those skilled in the art should be aware that the embodiments of the present application are not limited by the described order of actions, because according to the embodiments of the present application, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all preferred embodiments, and the actions involved are not necessarily required by the embodiments of the present application.

[0161] Figure 6The structure diagram of a coding rate acquisition device 20 of a quantum key distribution device provided by the present application is schematically shown, and the device includes:

[0162] A simulation module 201 is used to simulate the startup process of a quantum key device, and initialize the key quantity, coding time and polarization modulation deviation angle of the quantum key device;

[0163] When the current time is less than the preset coding statistical time, the polarization drift in the optical fiber is modeled using a one-dimensional Brownian motion model, the polarization deviation angle is simulated and calculated in real time, and then the signal state error rate of the key distribution device is obtained based on the polarization modulation deviation angle, and the self-test process of the key distribution device is simulated;

[0164] When the signal state error rate is greater than or equal to the error rate threshold, simulating a restart process of the quantum key device, initializing the polarization modulation deviation angle, and adjusting the coding time using the time of the restart process;

[0165] When the signal state error rate is less than the error rate threshold, the coding time is accumulated, the polarization modulation deviation angle is adjusted based on the normal distribution parameter, the key amount is accumulated based on the polarization modulation deviation angle, and it is re-determined whether the current time is less than the preset coding statistical time;

[0166] The processing module 202 is used to calculate the coding rate of the quantum key distribution device based on the key amount and the coding time when the current time is greater than or equal to the preset coding statistical time.

[0167] Optionally, the simulation module 201 is further used for:

[0168] Modeling the polarization modulation deviation angle drift based on a one-dimensional Brownian motion model, wherein the polarization modulation deviation angle obtains the optical error rate of the key distribution device at the current moment;

[0169] The upper limit of the signal state error rate of the key distribution device at the current moment is obtained based on the optical error rate.

[0170] Optionally, the simulation module 201 is further used for:

[0171] Obtain the dark count rate of single photon detector based on the intrinsic dark count of single photon detector and the noise count introduced by Raman noise;

[0172] The signal state gain probability is obtained based on the dark count rate of the single-photon detector, the average number of photons in a single pulse of the signal state, the attenuation coefficient of quantum light in the optical fiber, the length of the optical fiber, the detection efficiency of the single-photon detector, and the losses other than the optical fiber loss;

[0173] Obtaining a lower limit value of the signal state gain probability according to the signal state gain probability, the number of signal state pulses, and the confidence level;

[0174] Based on the signal state optical error rate, vacuum state error rate, single photon detector dark count rate, signal state single pulse average photon number, quantum light attenuation coefficient in optical fiber, optical fiber length, single photon detector detection efficiency, and other losses except optical fiber loss, obtain the product of signal state measurement error rate and signal state gain probability;

[0175] Based on the product of the signal state measurement error rate and the signal state gain probability, the number of signal state pulses, and the confidence level, obtaining an upper limit value of the product of the signal state measurement error rate and the signal state gain probability;

[0176] Based on the upper limit value of the product of the signal state measurement error rate and the signal state gain probability and the lower limit value of the signal state gain probability, the upper limit value of the signal state error rate at the current moment is obtained.

[0177] Optionally, the simulation module 201 is further used for:

[0178] Calculating the amount of coding per unit time based on the polarization modulation deviation angle;

[0179] The amount of passwords is accumulated using the amount of codes generated in the unit time.

[0180] Optionally, the simulation module 201 is further used for:

[0181] Based on the polarization modulation deviation angle, an upper limit value of a signal state single photon pulse error rate and a lower limit value of a signal state single photon pulse response rate under Raman noise are obtained;

[0182] Based on the upper limit value of the signal state single-photon pulse error rate and the lower limit value of the signal state single-photon pulse response rate, the amount of coding per unit time is obtained.

[0183] Optionally, the simulation module 201 is further used for:

[0184] Based on the polarization modulation deviation angle, obtaining an optical error rate;

[0185] Acquire a signal state gain probability and a decoy state gain probability based on the optical error rate;

[0186] Obtaining a lower limit of the decoy state gain probability based on the decoy state gain probability, the number of decoy state pulses, and the confidence level;

[0187] Obtaining an upper limit of the signal state gain probability based on the signal state gain probability, the number of signal state pulses, and the confidence level;

[0188] Obtain the lower and upper limits of the dark count rate of the single-photon detector based on the dark count rate of the single-photon detector, the number of vacuum pulses, and the confidence level;

[0189] Based on the number of signal state pulses, the number of decoy state pulses, the confidence level, the vacuum state measurement error rate, the optical error rate, the dark count rate of the single-photon detector, the average number of photons in the signal state pulses, the average number of photons in the decoy state pulses, the attenuation coefficient of quantum light in the optical fiber, the optical fiber length, the detection efficiency of the single-photon detector, and the losses other than the optical fiber loss, the upper limit of the product of the signal state error rate and the gain probability and the upper limit of the product of the decoy state error rate and the gain probability are obtained;

[0190] Based on the lower limit of the decoy state gain probability, the upper limit of the signal state gain probability, the upper and lower limits of the dark count rate of the single-photon detector, the upper limit of the product of the signal state error rate and gain probability, the upper limit of the product of the decoy state error rate and gain probability, the vacuum state measurement error rate, the average photon number of the signal state pulse, and the average photon number of the decoy state pulse, the upper limit of the signal state single-photon pulse error rate and the lower limit of the signal state single-photon pulse response rate under Raman noise are obtained.

[0191] The embodiment of the present application uses a one-dimensional Brownian motion process to model the quantum state polarization drift phenomenon, and models the self-startup, self-checking and restart processes of the quantum key distribution device, quantitatively measures the impact of noise interference and device startup factors on the coding rate, and can more accurately obtain the coding rate of the quantum key distribution device in actual engineering.

[0192] The embodiment of the present application also provides a non-volatile readable storage medium, which stores one or more modules (programs). When the one or more modules are applied to a device, the device can execute instructions (instructions) of each method step in the embodiment of the present application.

[0193] The present application embodiment provides one or more machine-readable media, on which instructions are stored, and when executed by one or more processors, an electronic device executes one or more methods as described in the above embodiments. In the present application embodiment, the electronic device includes a server, a terminal device, and the like.

[0194] The embodiments of the present disclosure may be implemented as a device configured as desired using any appropriate hardware, firmware, software, or any combination thereof, and the device may include electronic devices such as a server (cluster), a terminal, etc. Figure 7 An exemplary apparatus 1000 that may be used to implement the embodiments described in this application is schematically illustrated.

[0195] For one embodiment, Figure 7An exemplary apparatus 1000 is shown having one or more processors 1002, a control module (chip set) 1004 coupled to at least one of the (one or more) processors 1002, a memory 1006 coupled to the control module 1004, a non-volatile memory (NVM) / storage device 1008 coupled to the control module 1004, one or more input / output devices 1010 coupled to the control module 1004, and a network interface 1012 coupled to the control module 1004.

[0196] The processor 1002 may include one or more single-core or multi-core processors, and the processor 1002 may include any combination of general-purpose processors or special-purpose processors (such as graphics processors, application processors, baseband processors, etc.). In some embodiments, the device 1000 can be used as a server, terminal, or other device described in the embodiments of the present application.

[0197] In some embodiments, the apparatus 1000 may include one or more computer-readable media (e.g., memory 1006 or NVM / storage device 1008) having instructions 1014 and one or more processors 1002 combined with the one or more computer-readable media and configured to execute the instructions 1014 to implement a module to perform the actions described in the present disclosure.

[0198] For one embodiment, the control module 1004 may include any suitable interface controller to provide any suitable interface to at least one of the processor(s) 1002 and / or any suitable device or component in communication with the control module 1004 .

[0199] The control module 1004 may include a memory controller module to provide an interface to the memory 1006. The memory controller module may be a hardware module, a software module, and / or a firmware module.

[0200] The memory 1006 may be used, for example, to load and store data and / or instructions 1014 for the device 1000. For one embodiment, the memory 1006 may include any suitable volatile memory, such as a suitable DRAM. In some embodiments, the memory 1006 may include double data rate type four synchronous dynamic random access memory (DDR4 SDRAM).

[0201] For one embodiment, control module 1004 may include one or more input / output controllers to provide an interface to NVM / storage device 1008 and input / output device(s) 1010 .

[0202] For example, NVM / storage 1008 may be used to store data and / or instructions 1014. NVM / storage 1008 may include any suitable non-volatile memory (e.g., flash memory) and / or may include any suitable non-volatile storage device(s) (e.g., one or more hard disk drives (HDDs), one or more compact disk (CD) drives, and / or one or more digital versatile disk (DVD) drives).

[0203] NVM / storage device 1008 may include storage resources that are part of the device on which apparatus 1000 is installed, or it may be accessible to the device without being part of the device. For example, NVM / storage device 1008 may be accessed via (one or more) input / output devices 1010 over a network.

[0204] (One or more) input / output devices 1010 may provide an interface for the apparatus 1000 to communicate with any other appropriate device, and the input / output device 1010 may include a communication component, an audio component, a sensor component, etc. The network interface 1012 may provide an interface for the apparatus 1000 to communicate through one or more networks, and the apparatus 1000 may wirelessly communicate with one or more components of a wireless network according to any of one or more wireless network standards and / or protocols, for example, accessing a wireless network based on a communication standard, such as WiFi, 2G, 3G, 4G, 5G, etc., or a combination thereof for wireless communication.

[0205] For one embodiment, at least one of the processor(s) 1002 may be packaged together with the logic of one or more controllers (e.g., a memory controller module) of the control module 1004. For one embodiment, at least one of the processor(s) 1002 may be packaged together with the logic of one or more controllers of the control module 1004 to form a system-in-package (SiP). For one embodiment, at least one of the processor(s) 1002 may be integrated on the same die with the logic of one or more controllers of the control module 1004. For one embodiment, at least one of the processor(s) 1002 may be integrated on the same die with the logic of one or more controllers of the control module 1004 to form a system-on-chip (SoC).

[0206] In an embodiment, the device 1000 may be, but is not limited to, a terminal device such as a server, a desktop computing device, or a mobile computing device (e.g., a laptop computing device, a handheld computing device, a tablet computer, a netbook, etc.). In an embodiment, the device 1000 may have more or fewer components and / or a different architecture. For example, in some embodiments, the device 1000 includes one or more cameras, a keyboard, a liquid crystal display (LCD) screen (including a touch screen display), a non-volatile memory port, multiple antennas, a graphics chip, an application-specific integrated circuit (ASIC), and a speaker.

[0207] Among them, the main control chip can be used as a processor or control module in the detection device, sensor data, location information, etc. are stored in a memory or NVM / storage device, the sensor group can be used as an input / output device, and the communication interface may include a network interface.

[0208] An embodiment of the present application further provides an electronic device, comprising: a processor; and a memory, on which executable code is stored, and when the executable code is executed, the processor executes one or more methods described in the embodiments of the present application.

[0209] The embodiments of the present application also provide one or more machine-readable media on which executable codes are stored. When the executable codes are executed, the processor executes one or more methods described in the embodiments of the present application.

[0210] As for the device embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0211] The embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referenced to each other.

[0212] The embodiments of the present application are described with reference to the flowcharts and / or block diagrams of the methods, terminal devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing terminal device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing terminal device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0213] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing terminal device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce a manufactured product including an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0214] These computer program instructions can also be loaded onto a computer or other programmable data processing terminal device so that a series of operating steps are executed on the computer or other programmable terminal device to produce a computer-implemented process, thereby providing instructions for executing on the computer or other programmable terminal device to implement the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0215] Although the preferred embodiments of the present application have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the embodiments of the present application.

[0216] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or terminal device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or terminal device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or terminal device including the elements.

[0217] The data processing method, the data processing device, the electronic device and the storage medium provided by the present application are introduced in detail above. The principles and implementation methods of the present application are explained in this article by using specific examples. The description of the above embodiments is only used to help understand the method of the present application and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A method for obtaining a coding rate of a quantum key distribution device, characterized in that: include: Simulating the startup process of a quantum key device to initialize the key quantity, coding time and polarization modulation deviation angle of the quantum key device; When the current time is less than the preset coding statistical time, the polarization drift in the optical fiber is modeled using a one-dimensional Brownian motion model, the polarization deviation angle is simulated and calculated in real time, and then the signal state error rate of the key distribution device is obtained based on the polarization modulation deviation angle, and the self-check process of the key distribution device is simulated; When the signal state error rate is greater than or equal to the error rate threshold, simulating a restart process of the quantum key device, initializing the polarization modulation deviation angle, and adjusting the coding time using the time of the restart process; When the signal state error rate is less than the error rate threshold, the coding time is accumulated, the polarization modulation deviation angle is adjusted based on the normal distribution parameter, the key amount is accumulated based on the polarization modulation deviation angle, and it is re-determined whether the current time is less than the preset coding statistical time; When the current time is greater than or equal to the preset coding statistical time, the coding rate of the quantum key distribution device is calculated based on the key amount and the coding time; Wherein, acquiring the signal state error rate of the key distribution device based on the polarization modulation deviation angle includes: Modeling the polarization modulation deviation angle drift based on a one-dimensional Brownian motion model, wherein the polarization modulation deviation angle obtains the optical error rate of the key distribution device at the current moment; Obtaining an upper limit of a signal state error rate of the key distribution device at a current moment based on the optical error rate; Wherein, obtaining the upper limit of the signal state error rate of the key distribution device at the current moment based on the optical error rate includes: Obtain the dark count rate of single photon detector based on the intrinsic dark count of single photon detector and the noise count introduced by Raman noise; The signal state gain probability is obtained based on the dark count rate of the single-photon detector, the average number of photons in a single pulse of the signal state, the attenuation coefficient of quantum light in the optical fiber, the length of the optical fiber, the detection efficiency of the single-photon detector, and the losses other than the optical fiber loss; Obtaining a lower limit value of the signal state gain probability according to the signal state gain probability, the number of signal state pulses, and the confidence level; Based on the signal state optical error rate, vacuum state error rate, single photon detector dark count rate, signal state single pulse average photon number, quantum light attenuation coefficient in optical fiber, optical fiber length, single photon detector detection efficiency, and other losses except optical fiber loss, obtain the product of signal state measurement error rate and signal state gain probability; Based on the product of the signal state measurement error rate and the signal state gain probability, the number of signal state pulses, and the confidence level, obtaining an upper limit value of the product of the signal state measurement error rate and the signal state gain probability; Based on the upper limit value of the product of the signal state measurement error rate and the signal state gain probability and the lower limit value of the signal state gain probability, obtain the upper limit value of the signal state error rate at the current moment; The step of accumulating the key amount based on the polarization modulation deviation angle includes: Calculating the amount of coding per unit time based on the polarization modulation deviation angle; Accumulating the key amount by using the amount of code generated in the unit time; The step of calculating the amount of coding per unit time based on the polarization modulation deviation angle includes: Based on the polarization modulation deviation angle, an upper limit value of a signal state single photon pulse error rate and a lower limit value of a signal state single photon pulse response rate under Raman noise are obtained; Based on the upper limit value of the signal state single-photon pulse error rate and the lower limit value of the signal state single-photon pulse response rate, the amount of coding per unit time is obtained.

2. The method according to claim 1, characterized in that: The obtaining, based on the polarization modulation deviation angle, an upper limit value of a signal state single photon pulse error rate and a lower limit value of a signal state single photon pulse response rate under Raman noise includes: Based on the polarization modulation deviation angle, obtaining an optical error rate; Acquire a signal state gain probability and a decoy state gain probability based on the optical error rate; Obtaining a lower limit of the decoy state gain probability based on the decoy state gain probability, the number of decoy state pulses, and the confidence level; Obtaining an upper limit of the signal state gain probability based on the signal state gain probability, the number of signal state pulses, and the confidence level; Obtain the lower and upper limits of the dark count rate of the single-photon detector based on the dark count rate of the single-photon detector, the number of vacuum pulses, and the confidence level; Based on the number of signal state pulses, the number of decoy state pulses, the confidence level, the vacuum state measurement error rate, the optical error rate, the dark count rate of the single-photon detector, the average number of photons in the signal state pulses, the average number of photons in the decoy state pulses, the attenuation coefficient of quantum light in the optical fiber, the optical fiber length, the detection efficiency of the single-photon detector, and the losses other than the optical fiber loss, the upper limit of the product of the signal state error rate and the gain probability and the upper limit of the product of the decoy state error rate and the gain probability are obtained; Based on the lower limit of the decoy state gain probability, the upper limit of the signal state gain probability, the upper and lower limits of the dark count rate of the single-photon detector, the upper limit of the product of the signal state error rate and gain probability, the upper limit of the product of the decoy state error rate and gain probability, the vacuum state measurement error rate, the average photon number of the signal state pulse, and the average photon number of the decoy state pulse, the upper limit of the signal state single-photon pulse error rate and the lower limit of the signal state single-photon pulse response rate under Raman noise are obtained.

3. A coding rate acquisition device for a quantum key distribution device, characterized in that: The device comprises: A simulation module, used to simulate the startup process of a quantum key device, and initialize the key quantity, coding time and polarization modulation deviation angle of the quantum key device; When the current time is less than the preset coding statistical time, the polarization drift in the optical fiber is modeled using a one-dimensional Brownian motion model, the polarization deviation angle is simulated and calculated in real time, and then the signal state error rate of the key distribution device is obtained based on the polarization modulation deviation angle, and the self-test process of the key distribution device is simulated; When the signal state error rate is greater than or equal to the error rate threshold, simulating a restart process of the quantum key device, initializing the polarization modulation deviation angle, and adjusting the coding time using the time of the restart process; When the signal state error rate is less than the error rate threshold, the coding time is accumulated, the polarization modulation deviation angle is adjusted based on the normal distribution parameter, the key amount is accumulated based on the polarization modulation deviation angle, and it is re-determined whether the current time is less than the preset coding statistical time; A processing module, configured to calculate a coding rate of the quantum key distribution device based on the key quantity and the coding time when the current time is greater than or equal to a preset coding statistical time; Wherein, the simulation module is also used for: Modeling the polarization modulation deviation angle drift based on a one-dimensional Brownian motion model, wherein the polarization modulation deviation angle obtains the optical error rate of the key distribution device at the current moment; Obtaining an upper limit of a signal state error rate of the key distribution device at a current moment based on the optical error rate; Wherein, the simulation module is also used for: Obtain the dark count rate of single photon detector based on the intrinsic dark count of single photon detector and the noise count introduced by Raman noise; The signal state gain probability is obtained based on the dark count rate of the single-photon detector, the average number of photons in a single pulse of the signal state, the attenuation coefficient of quantum light in the optical fiber, the length of the optical fiber, the detection efficiency of the single-photon detector, and the losses other than the optical fiber loss; Obtaining a lower limit value of the signal state gain probability according to the signal state gain probability, the number of signal state pulses, and the confidence level; Based on the signal state optical error rate, vacuum state error rate, single photon detector dark count rate, signal state single pulse average photon number, quantum light attenuation coefficient in optical fiber, optical fiber length, single photon detector detection efficiency, and other losses except optical fiber loss, obtain the product of signal state measurement error rate and signal state gain probability; Based on the product of the signal state measurement error rate and the signal state gain probability, the number of signal state pulses, and the confidence level, obtaining an upper limit value of the product of the signal state measurement error rate and the signal state gain probability; Based on the upper limit value of the product of the signal state measurement error rate and the signal state gain probability and the lower limit value of the signal state gain probability, obtain the upper limit value of the signal state error rate at the current moment; Calculating the amount of coding per unit time based on the polarization modulation deviation angle; Accumulating the key amount by using the amount of code generated in the unit time; Based on the polarization modulation deviation angle, an upper limit value of a signal state single photon pulse error rate and a lower limit value of a signal state single photon pulse response rate under Raman noise are obtained; Based on the upper limit value of the signal state single-photon pulse error rate and the lower limit value of the signal state single-photon pulse response rate, the amount of coding per unit time is obtained.

4. A computing and processing device, characterized in that: include: a memory having computer readable code stored therein; One or more processors, when the computer readable code is executed by the one or more processors, the computing processing device executes the coding rate acquisition method of the quantum key distribution device according to any one of claims 1 to 2.

5. A non-transitory computer-readable medium, characterized in that A computer program for a method for acquiring a coding rate of a quantum key distribution device as described in any one of claims 1 to 2 is stored therein.

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