Quantum key transmission method and device, storage medium and electronic equipment

Abstract

The invention provides a quantum key transmission method and device, a storage medium and electronic equipment. The method comprises the following steps: generating a to-be-transmitted key data sequence; sending the key data sequence to a preset receiving end through a quantum channel; performing hierarchical quantization on the key data sequence to obtain first quantization information of the key data sequence; generating a syndrome according to the first quantization information and a preset check matrix; and sending the syndrome to the receiving end, so that the receiving end processes the syndrome and second quantized information by using a preset QC-LDPC code through an FPGA circuit to obtain a key data sequence, and the second quantized information is obtained by layering and quantifying a signal received through the quantum channel by the receiving end. By applying the method provided by the embodiment of the invention, the receiving end can decode through the FPGA circuit, and the decoding rate is effectively improved, so that the key data sequence can be quickly and accurately obtained.

Description

Technical Field

[0001] The present application relates to the field of quantum technology, and in particular to a quantum key transmission method, device, storage medium and electronic device. Background Art

[0002] In recent years, with the development of quantum information technology, quantum key distribution (QKD) has attracted widespread attention as an information encryption technology that can provide unconditional security guarantees. Among them, the continuous variable quantum key distribution system is considered a promising secure communication solution because it can be implemented in existing fiber-optic communication networks.

[0003] However, in practical applications, traditional continuous-variable quantum key distribution systems typically rely on software simulation to implement functions such as signal processing and key extraction. While software simulation can verify the effectiveness of theoretical models in a laboratory environment, in practice, limited computing resources and software execution efficiency issues result in very low actual decoding rates, making it difficult for the receiver to quickly and accurately obtain key data. Summary of the Invention

[0004] The technical problem to be solved by this application is to provide a quantum key transmission method, device, storage medium, and electronic device that can improve the decoding rate. The specific solution is as follows:

[0005] A quantum key transmission method, comprising:

[0006] generating a key data sequence to be transmitted;

[0007] The key data sequence is sent to the preset receiving end through the quantum channel;

[0008] performing hierarchical quantization on the key data sequence to obtain first quantization information of the key data sequence;

[0009] generating a syndrome according to the first quantization information and a preset check matrix;

[0010] The syndrome is sent to the receiving end, so that the receiving end processes the syndrome and second quantization information using a preset QC-LDPC code through an FPGA circuit to obtain a key data sequence, where the second quantization information is obtained by performing hierarchical quantization on a signal received through the quantum channel at the receiving end.

[0011] Optionally, in the above method, the step of transmitting the key data sequence to a preset receiving end via a preset quantum channel includes:

[0012] Inputting the key sequence data into a preset waveform generator to obtain a key data sequence signal obeying Gaussian distribution;

[0013] The key data sequence signal is sent to the preset receiving end through the quantum channel.

[0014] In the above method, optionally, performing hierarchical quantization on the key data sequence to obtain first quantization information of the key data sequence includes:

[0015] Determining a signal-to-noise ratio corresponding to the key data sequence;

[0016] The key data sequence is hierarchically quantized according to the signal-to-noise ratio and a preset hierarchical parameter to obtain first quantization information of the key data sequence.

[0017] Optionally, in the above method, generating a syndrome according to the first quantization information and a preset check matrix includes:

[0018] The first quantization information is multiplied by a preset check matrix to obtain a syndrome.

[0019] A quantum key transmission device, comprising:

[0020] A first generating unit, configured to generate a key data sequence to be transmitted;

[0021] A key transmission unit, used to send the key data sequence to a preset receiving end through a quantum channel;

[0022] a quantization unit, configured to perform hierarchical quantization on the key data sequence to obtain first quantization information of the key data sequence;

[0023] A second generating unit, configured to generate a syndrome according to the first quantization information and a preset check matrix;

[0024] A sending unit is configured to send the syndrome to the receiving end, so that the receiving end processes the syndrome and second quantization information using a preset QC-LDPC code through an FPGA circuit to obtain a key data sequence, where the second quantization information is obtained by performing hierarchical quantization on a signal received through the quantum channel at the receiving end.

[0025] In the above device, optionally, the key transmission unit includes:

[0026] An execution subunit, configured to input the key sequence data into a preset waveform generator to obtain a key data sequence signal obeying a Gaussian distribution;

[0027] The key transmission subunit is used to send the key data sequence signal to the preset receiving end through the quantum channel.

[0028] In the above device, optionally, the quantization unit includes:

[0029] a determination subunit, configured to determine a signal-to-noise ratio corresponding to the key data sequence;

[0030] The quantization subunit is used to perform hierarchical quantization on the key data sequence according to the signal-to-noise ratio and a preset hierarchical parameter to obtain first quantization information of the key data sequence.

[0031] In the above device, optionally, the second generating unit includes:

[0032] The calculation subunit is configured to multiply the first quantization information by a preset check matrix to obtain a syndrome.

[0033] A storage medium includes stored instructions, wherein when the instructions are executed, the device where the storage medium is located is controlled to execute the quantum key transmission method as described above.

[0034] An electronic device includes a memory and one or more instructions, wherein the one or more instructions are stored in the memory and configured to be executed by one or more processors to perform the quantum key transmission method as described above.

[0035] Based on the above-mentioned implementation of this application, a quantum key transmission method, device, storage medium and electronic device are provided. The method includes: generating a key data sequence to be transmitted; sending the key data sequence to a preset receiving end through a quantum channel; performing hierarchical quantization on the key data sequence to obtain first quantization information of the key data sequence; generating a syndrome according to the first quantization information and a preset check matrix; sending the syndrome to the receiving end so that the receiving end processes the syndrome and the second quantization information using a preset QC-LDPC code through an FPGA circuit to obtain a key data sequence, and the second quantization information is obtained by the receiving end performing hierarchical quantization on the signal received through the quantum channel. Applying the method provided in the embodiment of this application, the receiving end can decode through the FPGA circuit, effectively improving the decoding rate, so that the key data sequence can be obtained quickly and accurately. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without any creative work.

[0037] Figure 1 A flowchart of a quantum key transmission method provided in this application;

[0038] Figure 2 A flowchart of a process for sending a key data sequence to a receiving end provided by the present application;

[0039] Figure 3 A flowchart of a process of processing syndromes and second quantization information by an FPGA provided in this application;

[0040] Figure 4 A schematic diagram of a quantum key transmission process provided in this application;

[0041] Figure 5 A schematic diagram of the structure of a quantum key transmission device provided in this application;

[0042] Figure 6 This is a schematic diagram of the structure of an electronic device provided in this application. DETAILED DESCRIPTION

[0043] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0044] In this application, the terms "comprises," "comprising," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not preclude the presence of additional identical elements in the process, method, article, or apparatus that includes the element.

[0045] The embodiment of the present application provides a quantum key transmission method, which can be applied to electronic devices, such as smart phones, tablet devices, smart wearable devices, etc. The method flow chart is as follows: Figure 1 As shown, specifically including:

[0046] S101: Generate a key data sequence to be transmitted.

[0047] In this embodiment, the key data sequence may be key data that obeys Gaussian distribution.

[0048] S102: Send the key data sequence to a preset receiving end via the quantum channel.

[0049] Optionally, the key data sequence can be sent to a preset receiving end via a quantum channel of a quantum key distribution system.

[0050] In one embodiment provided in the present application, based on the above solution, optionally, the process of sending the key data sequence to the preset receiving end through the preset quantum channel is as follows: Figure 2 Shown, including:

[0051] S201: Inputting the key sequence data into a preset waveform generator to obtain a key data sequence signal obeying Gaussian distribution.

[0052] S202: Send the key data sequence signal to a preset receiving end through the quantum channel.

[0053] In this embodiment, the key data sequence signal may be a quantum light pulse signal. When the key data sequence signal is sent to a preset receiving end through a quantum channel, the signal-to-noise ratio corresponding to the key data sequence may be calculated.

[0054] S103: Perform hierarchical quantization on the key data sequence to obtain first quantization information of the key data sequence.

[0055] In an embodiment provided by the present application, based on the above solution, optionally, performing hierarchical quantization on the key data sequence to obtain first quantization information of the key data sequence includes:

[0056] Determining a signal-to-noise ratio corresponding to the key data sequence;

[0057] The key data sequence is hierarchically quantized according to the signal-to-noise ratio and a preset hierarchical parameter to obtain first quantization information of the key data sequence.

[0058] In this embodiment, after the key data sequence is hierarchically quantized, the quantization interval length and hierarchical parameters of the first quantization information may be sent to the receiving end.

[0059] S104: Generate a syndrome according to the first quantization information and a preset check matrix.

[0060] In an embodiment provided in the present application, based on the above solution, optionally, generating a syndrome according to the first quantization information and a preset check matrix includes:

[0061] The first quantization information is multiplied by a preset check matrix to obtain a syndrome.

[0062] S105: Sending the syndrome to the receiving end, so that the receiving end processes the syndrome and second quantization information using a preset QC-LDPC code through an FPGA circuit to obtain a key data sequence. The second quantization information is obtained by performing hierarchical quantization on a signal received through the quantum channel at the receiving end.

[0063] In this embodiment, the receiving end may input the syndrome and the second quantization information into a preset FPGA circuit, so that the FPGA circuit processes the syndrome and the second quantization information using a preset QC-LDPC code to obtain a key data sequence.

[0064] Optionally, the QC-LDPC code construction method is as follows:

[0065]

[0066] In this embodiment, H QC For a parity check matrix, during the construction process, the original binary basic matrix of dimension m×n can be expanded by the cyclic shift number matrix to become a final check matrix of size mL×nL, where n is the number of rows, m is the number of columns, and b is the matrix. The 0s in the original matrix are expanded into an L×L square matrix of all zeros, and the 1s in the original matrix are expanded into a matrix with the number of shifts pij.

[0067] In this embodiment, for the Gaussian modulated coherent state continuous variable quantum key distribution system, the original data X and Y at both ends of the transmitter and receiver satisfy:

[0068] Y=X+Z

[0069] Among them, X is the signal sent by the transmitter, Y is the signal received by the receiver, and Z is the noise brought by the channel. They all obey the Gaussian distribution X~N(0,V A ), Z~N(0,σ 2 ), Y~N(0,σ 2 ), where VA is the modulation variance, σ 2 is the noise variance.

[0070] To address the information loss caused by quantization, the quantization efficiency of output negotiation is defined as:

[0071]

[0072] Among them, β slice represents quantization efficiency, I refers to mutual information, and Q(X) represents the discrete variable after quantization, which means that the selection of quantization interval and number of layers should maximize the mutual information between the communicating parties and maximize the quantization efficiency.

[0073] Optionally, the process of processing the syndrome and the second quantization information by using a preset QC-LDPC code through an FPGA circuit is as follows: Figure 3 As shown, the original signal received by the receiver can be converted into the initial channel likelihood value Perform calculations, quantize the original signal, obtain the second quantized information, and store it in the memory INT-RAM, and store the received syndrome in the synchronous memory SYN-RAM module for the variable node processing unit to read. The variable node processing unit in the decoding processing module converts the variable information into verification information through circuit calculation and stores the data in VNU-RAM. After the variable node processing unit completes the processing, the verification node processing unit in the decoding processing module converts the verification information stored in VNU-RAM into variable information and stores it in CNU-RAM. The judgment output module judges the obtained likelihood ratio data and stores it in FINAL-RAM. When the number of iterations reaches the set number or the updated syndrome information is consistent with the original information, the decoding ends, where y i is the i-th value obtained by the receiver.

[0074] Using the method provided in the embodiments of this application, a key data sequence to be transmitted can be generated; the key data sequence can be sent to a preset receiving end via a quantum channel; the key data sequence can be hierarchically quantized to obtain first quantization information of the key data sequence; a syndrome can be generated based on the first quantization information and a preset parity check matrix; and the syndrome can be sent to the receiving end, so that the receiving end processes the syndrome and second quantization information using a preset QC-LDPC code via an FPGA circuit to obtain the key data sequence. The second quantization information is obtained by hierarchically quantizing the signal received via the quantum channel at the receiving end. In this embodiment, decoding at the receiving end using the FPGA circuit can effectively improve the decoding rate, thereby quickly and accurately obtaining the key data sequence.

[0075] In the examples provided in this application, Figure 4 As shown in the figure, the key data sequence can be transmitted from the transmitter in the continuous variable quantum key distribution system to the receiver through the quantum channel, and then the layered quantization parameters and syndromes are transmitted through the classical channel. Finally, the receiver implements QC-LDPC error correction based on FPGA. The specific process is as follows:

[0076] Step 1: The transmitter first generates a key data sequence that obeys a Gaussian distribution. Then, based on information such as the signal-to-noise ratio, it performs hierarchical quantization on the continuous variable and transmits the hierarchical quantization parameters through the classical channel. The hierarchical quantization parameters include the quantization interval length and the hierarchical parameters.

[0077] Step 1.1: Generate a key data sequence that obeys Gaussian distribution, and use a waveform generator to generate a key data sequence signal.

[0078] Step 1.2: Send the key data sequence signal through the quantum channel and calculate the signal-to-noise ratio to evaluate the quantization interval length.

[0079] Step 1.3: Send the quantization interval length and the number of quantization layers to the receiver through the classical channel.

[0080] Step 2: The receiving end quantizes the received signal based on the public channel information. The transmitting end then generates a syndrome based on the parity check matrix shared by both parties and sends it to the receiving end. Finally, based on this syndrome, the FPGA hardware circuit extracts the consistent key information of both parties.

[0081] Step 2.1: Use a coherent detector to detect the signal and perform hierarchical quantization on the received information to obtain a key data sequence.

[0082] Step 2.2: The sending end generates a syndrome and sends it to the receiving end.

[0083] Step 2.3: The receiving end stores the check subsequence into the FPGA hardware circuit and inputs the obtained data series into the FPGA circuit for error correction using the QC-LDPC code, so that both the sender and the receiver obtain the same key sequence.

[0084] In this embodiment, in a continuous variable quantum key distribution system, the legitimate sender first generates a quantum light pulse signal that follows a Gaussian distribution and then performs multi-layer quantization based on information such as the estimated signal-to-noise ratio. Taking four-layer equally spaced quantization coding as an example, when N = 4, it can be divided into 24 = 16 intervals, each of which can be encoded at four levels. At a signal-to-noise ratio of 0, the quantization efficiency is approximately 99%. Assuming the initial data is 0.5, the chip negotiation encoding will result in (1, 0, 0, 1).

[0085] After passing through the channel, the legal receiver receives the optical signal and obtains the output electrical signal through coherent detection. According to the layered information shared by the classical channel, the binary data sequence is also obtained. The sender multiplies the data sequence with the LDPC check matrix to obtain the syndrome and sends it to the receiver through the classical channel and stores it in the SYN-RAM module. The initial probability is calculated using an iterative belief propagation algorithm and a minimum sum-product approach. Since BPSK modulation is used, the judgment is 1 when the maximum likelihood probability is less than 0, and 0 otherwise. The decoded data is also compared with the syndrome. If they are consistent, decoding ends; otherwise, the next decoding step is performed.

[0086] In this embodiment, the maximum likelihood probability is determined by the LLR value (i.e., log(a / b)), where a and b are the posterior probabilities. The positive and negative signs are used to determine whether the random variable is 0 or 1, and its absolute value indicates the confidence level of the value 0 or 1.

[0087] and Figure 1 Corresponding to the method, the embodiment of the present application also provides a quantum key transmission device for Figure 1 The specific implementation of the method is shown in the following diagram: Figure 5 As shown, including:

[0088] A first generating unit 501 is configured to generate a key data sequence to be transmitted;

[0089] A key transmission unit 502 is used to send a key data sequence to a predetermined receiving end via a quantum channel;

[0090] a quantization unit 503, configured to perform hierarchical quantization on the key data sequence to obtain first quantization information of the key data sequence;

[0091] A second generating unit 504 is configured to generate a syndrome according to the first quantization information and a preset check matrix;

[0092] A sending unit 505 is configured to send the syndrome to the receiving end, so that the receiving end processes the syndrome and second quantization information using a preset QC-LDPC code through an FPGA circuit to obtain a key data sequence. The second quantization information is obtained by performing hierarchical quantization on a signal received through the quantum channel at the receiving end.

[0093] In an embodiment provided in the present application, based on the above solution, optionally, the key transmission unit 502 includes:

[0094] An execution subunit, configured to input the key sequence data into a preset waveform generator to obtain a key data sequence signal obeying a Gaussian distribution;

[0095] The key transmission subunit is used to send the key data sequence signal to the preset receiving end through the quantum channel.

[0096] In an embodiment provided in the present application, based on the above solution, optionally, the quantization unit includes:

[0097] a determination subunit, configured to determine a signal-to-noise ratio corresponding to the key data sequence;

[0098] The quantization subunit is used to perform hierarchical quantization on the key data sequence according to the signal-to-noise ratio and a preset hierarchical parameter to obtain first quantization information of the key data sequence.

[0099] In an embodiment provided in the present application, based on the above solution, optionally, the second generating unit includes:

[0100] The calculation subunit is configured to multiply the first quantization information by a preset check matrix to obtain a syndrome.

[0101] The specific principles and execution processes of each unit and module in the quantum key transmission device disclosed in the above-mentioned embodiment of the present application are the same as those of the quantum key transmission method disclosed in the above-mentioned embodiment of the present application. Please refer to the corresponding parts of the quantum key transmission method provided in the above-mentioned embodiment of the present application, and no further details will be given here.

[0102] An embodiment of the present application further provides a storage medium, which includes stored instructions, wherein when the instructions are executed, the device where the storage medium is located is controlled to execute the above-mentioned quantum key transmission method.

[0103] The present application also provides an electronic device, the structure of which is shown in FIG. Figure 6 As shown, the system specifically includes a memory 601 and one or more instructions 602, wherein the one or more instructions 602 are stored in the memory 601 and are configured to be executed by one or more processors 603 to perform the following operations:

[0104] generating a key data sequence to be transmitted;

[0105] The key data sequence is sent to the preset receiving end through the quantum channel;

[0106] performing hierarchical quantization on the key data sequence to obtain first quantization information of the key data sequence;

[0107] generating a syndrome according to the first quantization information and a preset check matrix;

[0108] The syndrome is sent to the receiving end, so that the receiving end processes the syndrome and second quantization information using a preset QC-LDPC code through an FPGA circuit to obtain a key data sequence, where the second quantization information is obtained by performing hierarchical quantization on a signal received through the quantum channel at the receiving end.

[0109] It should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. Similarities between the various embodiments can be referred to in conjunction with each other. For device embodiments, since they are generally similar to method embodiments, their description is relatively simple, and for relevant details, reference can be made to the description of the method embodiments.

[0110] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are merely used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations.

[0111] For the convenience of description, the above devices are described as being divided into various units according to their functions. Of course, when implementing this application, the functions of each unit can be implemented in the same or multiple software and / or hardware.

[0112] Through the description of the above embodiments, it can be seen that those skilled in the art can clearly understand that the present application can be implemented by means of software plus a necessary general hardware platform. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a software product, which can be stored in a storage medium such as ROM / RAM, a magnetic disk, an optical disk, etc., and includes a number of instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in various embodiments of the present application or certain parts of the embodiments.

[0113] The above is a detailed introduction to a quantum key transmission method provided by the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method and core ideas of the present application. At the same time, for those skilled in the art, based on the ideas of the present application, there may be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as limiting the present application.

Claims

1. A quantum key transmission method, It is characterized in that include: generating a key data sequence to be transmitted; Sending the key data sequence to a preset receiving end through a preset quantum channel; Performing hierarchical quantization on the key data sequence to obtain first quantization information of the key data sequence; generating a syndrome according to the first quantization information and a preset check matrix; The syndrome is sent to the receiving end, so that the receiving end processes the syndrome and the second quantization information by using a preset QC-LDPC code through an FPGA circuit to obtain a key data sequence, where the second quantization information is obtained by the receiving end performing hierarchical quantization on a signal received through the quantum channel.

2. The method according to claim 1, It is characterized in that The step of sending the key data sequence to a preset receiving end through a preset quantum channel includes: Inputting the key sequence data into a preset waveform generator to obtain a key data sequence signal obeying Gaussian distribution; The key data sequence signal is sent to the preset receiving end through the quantum channel.

3. The method according to claim 1, It is characterized in that The step of performing hierarchical quantization on the key data sequence to obtain first quantization information of the key data sequence includes: Determining a signal-to-noise ratio corresponding to the key data sequence; The key data sequence is hierarchically quantized according to the signal-to-noise ratio and preset hierarchical parameters to obtain first quantization information of the key data sequence.

4. The method according to claim 1, It is characterized in that The generating a syndrome according to the first quantization information and a preset check matrix includes: The first quantization information is multiplied by a preset check matrix to obtain a syndrome.

5. A quantum key transmission device, It is characterized in that include: A first generating unit, used for generating a key data sequence to be transmitted; A key transmission unit, used to send a key data sequence to a preset receiving end through a quantum channel; A quantization unit, used for performing hierarchical quantization on the key data sequence to obtain first quantization information of the key data sequence; A second generating unit, configured to generate a syndrome according to the first quantization information and a preset check matrix; A sending unit is used to send the syndrome to the receiving end, so that the receiving end processes the syndrome and the second quantization information by using a preset QC-LDPC code through an FPGA circuit to obtain a key data sequence, where the second quantization information is obtained by the receiving end performing hierarchical quantization on a signal received through the quantum channel.

6. The device according to claim 5, It is characterized in that The key transmission unit comprises: An execution subunit, used for inputting the key sequence data into a preset waveform generator to obtain a key data sequence signal obeying a Gaussian distribution; The key transmission subunit is used to send the key data sequence signal to a preset receiving end through a quantum channel.

7. The device according to claim 5, It is characterized in that The quantization unit comprises: A determination subunit, used to determine a signal-to-noise ratio corresponding to the key data sequence; The quantization subunit is used to perform hierarchical quantization on the key data sequence according to the signal-to-noise ratio and a preset hierarchical parameter to obtain first quantization information of the key data sequence.

8. The device according to claim 6, It is characterized in that The second generating unit comprises: The calculation subunit is used to multiply the first quantization information by a preset check matrix to obtain a syndrome.

9. A storage medium, It is characterized in that The storage medium includes storage instructions, wherein when the instructions are executed, the device where the storage medium is located is controlled to execute the quantum key transmission method according to any one of claims 1 to 4.

10. An electronic device, It is characterized in that It comprises a memory and one or more instructions, wherein the one or more instructions are stored in the memory and are configured to be executed by one or more processors to perform the quantum key transmission method as described in any one of claims 1 to 4.

Images