Security protection method for Beidou global data elements

Abstract

The invention provides a Beidou global data element security protection method, and relates to the technical field of data encryption, and the method comprises the steps: 1, a user side sends a request for applying for a quantum key; 2, the quantum key distribution device distributes quantum keys to the user side and the Beidou ground central station; step 3, the user side carries out encryption by using the quantum key; 4, after receiving the encrypted data, the ground central station decrypts the encrypted data to obtain corresponding Beidou data elements; 5, the ground central station carries out encryption through a quantum key in combination with an AES encryption algorithm; and step 6, the user side uses the quantum key to carry out AES decryption processing. Through combination of Beidou short message communication and quantum communication and combination of the quantum key and the symmetric encryption algorithm AES algorithm, higher security and encryption and decryption efficiency of a traditional encryption mode are provided, and data security of Beidou global data elements of a Beidou satellite navigation system is protected.

Description

Technical Field

[0001] The present application relates to the field of data encryption technology, and in particular to a method for protecting the security of Beidou global data elements. Background Art

[0002] Beidou global data elements refer to spatiotemporal data elements built on the Beidou Navigation Satellite System (BDS). These data elements cover high-precision positioning, real-time updates, and two- and three-dimensional integrated spatiotemporal information. Beidou global data elements are widely used in many fields, such as intelligent transportation, environmental monitoring, and agricultural management. For example, in advanced autonomous driving, vehicles can achieve more accurate trajectory tracking by sharing data obtained by local sensors; in geological surveys, the Beidou system provides a comprehensive solution from data collection to emergency command.

[0003] However, in the prior art, the security protection of Beidou global data elements mostly adopts symmetric encryption algorithms or asymmetric encryption algorithms. In symmetric encryption algorithms, since the key needs to be transmitted to the recipient, the key leakage will lead to the theft of the transmitted data during the transmission process; while in asymmetric encryption algorithms, the characteristics of some functions in mathematics (such as the characteristics that the function value is easy to calculate according to the parameter, and the parameter is difficult to infer according to the function value) are used to adopt the method of public key encryption and private key decryption. Only the public key is transmitted in the communication, thereby ensuring the security of the communication information. The security of this method depends entirely on an assumption that is not absolutely safe: the inverse function of the encryption function is difficult to obtain. However, with the development of quantum computers, it can speed up the solution of some complex computing problems exponentially or polynomially. It is only a matter of time before the brute force cracking of asymmetric encryption algorithms is carried out. The data in the Beidou navigation system involves a large amount of personal privacy and commercial secrets. Once leaked, it will pose a serious threat to user privacy and national security. Summary of the invention

[0004] The present application is made in view of the above-mentioned problems, and its purpose is to provide a security protection method for Beidou global data elements. This application not only improves the security of Beidou short message communication through the combination of Beidou short message communication and quantum communication, but also utilizes the high concealment and super security characteristics of quantum communication, as well as the combination of quantum key and symmetric encryption algorithm AES algorithm, to provide higher security and encryption and decryption efficiency than traditional encryption methods, protect the data security of Beidou global data elements of the Beidou satellite navigation system, and provide strong protection for information security in the fields of national defense, finance, government affairs, etc.

[0005] Specifically, the first aspect of the present application provides a Beidou global data element security protection method, comprising the following steps:

[0006] Step 1: The user sends a request for a quantum key to the quantum key distribution device and informs the Beidou ground center station of its address information;

[0007] Before starting communication, the quantum key distribution equipment of the user end and the Beidou ground center station must be calibrated and configured, including the light source subsystem, single-photon detector, photoelectric converter and time-to-digital converter. The light source subsystem is used for quantum state preparation and can produce different polarizations; the single-photon detector is used to detect selected single photons; the photoelectric converter is used to convert the detected single photons into electrical pulse signals; the time-to-digital converter converts the time interval into a pulse signal through a pulse signal generator, and then converts the pulse signal into a voltage signal through an integrator, and finally outputs a digital signal.

[0008] Step 2: After receiving the request, the quantum key distribution device generates and distributes the same quantum key to the user terminal and the Beidou ground center station through the quantum channel;

[0009] Quantum key distribution uses the basic principles of quantum mechanics to ensure the security of communications, allowing both communicating parties to generate and share a random and secure key for encryption and decryption of information.

[0010] Specifically, quantum key distribution mainly relies on the transmission and measurement of quantum states. The sender uses a light source to randomly select the ground state of photons, sends these photons to the receiver through a quantum channel, and compares the measurement results through a classical channel to generate a shared key.

[0011] Step 3: The user end uses the quantum key obtained from the quantum key distribution device to encrypt the Beidou data element request and sends the encrypted request to the ground center station;

[0012] Step 4: After receiving the encrypted data, the ground central station uses the corresponding quantum key to decrypt it according to the quantum channel address, and obtains the corresponding Beidou data elements through the Beidou satellite;

[0013] The user end uses the quantum key to encrypt the Beidou data element request into a ciphertext, and then performs a decryption operation. The ground center station decrypts it using the same quantum key. The decryption process is usually the inverse operation of the encryption process.

[0014] Step 5: The ground center station encrypts the corresponding Beidou data elements by combining the quantum key with the AES encryption algorithm, and finally adds it to the outbound broadcast message that is continuously broadcast, and then broadcasts it to the user end via satellite;

[0015] The quantum key is combined with the AES encryption process. Specifically, the quantum key is used as the initial key of the AES encryption algorithm. The AES encryption algorithm sets the number of standard rounds according to the length of the quantum key, and expands the key to a sub-key that is consistent with the number of rounds. When encrypting, the quantum key is first XORed with the data to be transmitted, and then multiple rounds of encryption are performed through the standard round. Decryption is the inverse operation of the encryption operation.

[0016] Step 6: After receiving the outbound signal, the user end uses the quantum key to perform AES decryption and extract the required Beidou data elements.

[0017] Furthermore, the generating and distributing the same quantum key to the user terminal and the ground central station through the quantum channel specifically includes:

[0018] Step 1: The user end and the ground central station agree in advance to use two orthogonal polarization bases or phase bases;

[0019] Orthogonal polarization bases refer to two mutually perpendicular polarization states, which are perpendicular to each other in space. In quantum mechanics, due to the superposition principle, any polarization state can be superimposed by taking only two mutually orthogonal directions as the basis of vibration directions.

[0020] The phase basis usually refers to the basis related to the phase change of the electric field vector. The phase basis is used to describe the phase distribution characteristics of the light wave and realizes independent encoding of the polarization state of the light by controlling the phase and amplitude.

[0021] In quantum key distribution, orthogonal polarization bases are used to encode and decode the polarization state of photons, while phase bases are used to encode and decode the phase information of photons.

[0022] Step 2: The user terminal randomly selects a group of bits and randomly selects the corresponding polarization basis or phase basis as the basis vector to encode these bits, and sends the encoded quantum state to the ground center station through the quantum channel;

[0023] Polarization encoding can randomly prepare photons of various non-orthogonal polarization states, and can also randomly generate various non-orthogonal polarization state measurement bases, and detect and decode photons of various non-orthogonal polarization states. Phase-based encoding is to encode information on the phase of photons. Phase encoding can accurately compensate for the phase and polarization state of the photon state, thereby restoring the original polarization state of the photon, which can effectively reduce the bit error rate.

[0024] Step 3: After receiving the quantum states, the ground central station randomly selects basis vectors to measure these quantum states;

[0025] Basis vectors are a set of linearly independent and complete vectors that can be used to represent any quantum state. The quantum state is first projected onto the selected basis vectors. The basis vectors must satisfy the conditions of orthogonality and normalization. Through projection measurement, the probability distribution of the observable quantity at a certain specific value is obtained. When the communicating parties obtain consistent information, it means that the selected basis vectors are consistent and the communication has not been eavesdropped.

[0026] Step 4: The user end and the ground central station compare the basis vectors they selected through an open classical communication channel, discard the bits with inconsistent basis vectors, and retain the consistent bits as potential keys;

[0027] Step 5: Perform corresponding error correction and confidentiality enhancement processing on the potential key to form the final key and distribute the quantum key.

[0028] Furthermore, the corresponding error correction and confidentiality enhancement processing specifically includes: performing key error correction by using the SECDED error correction algorithm, and then performing confidentiality enhancement on the corrected key by using the hash algorithm SHA1.

[0029] The SECDED error correction algorithm can detect and correct single-bit errors and double-bit errors to ensure the integrity of the key. SHA1 can generate a 160-bit message digest, which can be used to verify the integrity and authenticity of the data. Due to the irreversibility of SHA1, the original data cannot be deduced from the hash value, so it is suitable for data confidentiality enhancement.

[0030] Furthermore, the quantum key distribution device needs to be equipped with the same device at the user end and the Beidou ground center station to establish a quantum channel.

[0031] Furthermore, the encryption process of the AES encryption algorithm includes an initial round and several standard rounds.

[0032] Furthermore, the encryption process is specifically as follows: performing an XOR operation with the plaintext data using an initial key in the initial round, and then performing multiple rounds of encryption through the standard round, wherein the standard round includes byte replacement, row shift, column confusion and round key addition operations.

[0033] Furthermore, in order to finally add it to the outbound broadcast message of continuous broadcast, the encrypted Beidou data elements need to be encapsulated in the form of Beidou short messages and then added to the outbound broadcast message, and the element data needs to be authenticated and authenticated through the HMAC algorithm to generate an integrity check code.

[0034] Furthermore, the Beidou data elements are encapsulated in the form of Beidou short messages and added to the outbound broadcast message, specifically including:

[0035] The encapsulated data packet is regarded as the information content of the Beidou short message, and the size of the encapsulated data packet is calculated. If the size of the transmitted information content exceeds the information content capacity limit of the Beidou short message at one time, the payload is split into multiple sub-payloads for transmission; if it is not greater than the capacity limit of the Beidou short message, the encapsulated data packet is added to the outbound broadcast message.

[0036] Furthermore, the payload is split into multiple sub-payloads for sending, and the split sub-payloads need to be re-packaged and grouped in the form of Beidou short messages. Each small packet after grouping cannot exceed the capacity limit of the Beidou short message. The small packet uses the serial number, the total number of packets and the packet number as the sub-packet identification.

[0037] Furthermore, the decryption process is performed using the corresponding quantum key according to the quantum channel address, and then the required Beidou data elements are extracted, specifically including: after decryption, judging whether the data packet is a complete data packet or a split sub-data packet through the mark on the data packet; if it is a complete data packet, directly verifying the integrity of the data packet through the integrity check code in the message; otherwise, waiting for the reception of data packets of the same sequence to be completed and then splicing them, and then verifying the integrity of the data packet.

[0038] In the second aspect, the present application also provides a computing device, which has the function of implementing the method described in the first aspect above. The beneficial effects can be found in the description of the first aspect, which will not be repeated here. The function can be implemented by hardware, or by executing the corresponding software implementation through hardware. The hardware or software includes one or more modules corresponding to the above functions. In one possible design, the structure of the device includes an acquisition module, a training module, and optionally, a construction module. These modules can implement the function of the training node in the method example of the first aspect above. Please refer to the detailed description in the method example for details, which will not be repeated here.

[0039] In the third aspect, the present application also provides a computing device, which is used to implement the functions of the method described in the first aspect above. The beneficial effects can be found in the description of the first aspect and will not be repeated here. The structure of the computing device includes a processor and a memory, and the memory is used to store instructions and / or data. The memory is coupled to the processor, and when the processor executes the program instructions stored in the memory, the function of the training node in the example of the first aspect above can be implemented. The structure of the computing device also includes a communication interface for communicating with other devices.

[0040] In a fourth aspect, the present application also provides a computer-readable storage medium, in which instructions are stored, and when the computer-readable storage medium is run on a computer, the computer executes the method in the above-mentioned first aspect and various possible designs of the first aspect.

[0041] In a fifth aspect, the present application also provides a computer program product comprising instructions, which, when executed on a computer, enables the computer to execute the method in the above-mentioned first aspect and various possible designs of the first aspect.

[0042] In a sixth aspect, the present application also provides a computing chip, which is connected to a memory, and the chip is used to read and execute a software program stored in the memory, and to execute the methods in the above-mentioned first aspect and various possible implementation methods of the first aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the embodiments of the present drawings or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present drawings. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0044] Figure 1 A flowchart of the steps of this application.

[0045] The purpose, features and advantages of this figure will be further described in conjunction with the embodiments with reference to the accompanying drawings. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application is described and illustrated below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not intended to limit the present application. Based on the embodiments provided in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present application.

[0047] Obviously, the drawings described below are only some examples or embodiments of the present application. For ordinary technicians in this field, the present application can also be applied to other similar scenarios based on these drawings without creative work. In addition, it can also be understood that although the efforts made in this development process may be complicated and lengthy, for ordinary technicians in this field related to the content disclosed in this application, some changes in design, manufacturing or production based on the technical content disclosed in this application are just conventional technical means, and should not be understood as insufficient content disclosed in this application.

[0048] Unless otherwise specified, all embodiments and optional embodiments of the present application can be combined with each other to form a new technical solution.

[0049] Unless otherwise specified, all technical features and optional technical features of this application can be combined with each other to form a new technical solution.

[0050] If there is no special explanation, all steps of the present application can be performed sequentially or randomly, preferably sequentially. For example, the method includes steps (a) and (b), which means that the method may include steps (a) and (b) performed sequentially, or may include steps (b) and (a) performed sequentially. For example, the method may further include step (c), which means that step (c) may be added to the method in any order. For example, the method may include steps (a), (b) and (c), or may include steps (a), (c) and (b), or may include steps (c), (a) and (b), etc.

[0051] If there is no special explanation, the "include" and "comprising" mentioned in this application are open-ended or closed-ended. For example, the "include" and "comprising" may mean that other components not listed may also be included or only the listed components may be included or only the listed components may be included.

[0052] If not specifically stated, in this application, the term "or" is inclusive. For example, the phrase "A or B" means "A, B, or both A and B". More specifically, any of the following conditions satisfies the condition "A or B": A is true (or exists) and B is false (or does not exist); A is false (or does not exist) and B is true (or exists); or both A and B are true (or exist).

[0053] In order to better understand the solutions of the embodiments of the present application, some relevant terms and concepts that may be involved in the embodiments of the present application are first introduced below.

[0054] (1) Quantum Key Distribution (QKD) is a technology that uses the principles of quantum mechanics to ensure that both parties in communication can securely share encryption keys. Its core idea is to achieve secure distribution of encryption keys through the encoding and transmission of quantum states, and any eavesdropping attempt will be detected.

[0055] (2) AES (Advanced Encryption Standard) is a widely used symmetric key encryption algorithm. It was released by the National Institute of Standards and Technology (NIST) in 2001 and became the Federal Information Processing Standard (FIPS PUBS197). The basic principle of AES is to divide data into blocks of fixed size (usually 128 bits) and then use one or more keys for encryption and decryption operations.

[0056] (3) SECDED (Single Error Correction, Double Error Detection) error correction algorithm can detect and correct single-bit errors and detect double-bit errors at the same time, thereby ensuring the integrity of the key. The corrected key is processed using the SHA1 hash algorithm, further enhancing the confidentiality of the key.

[0057] (4) SHA1 (Secure Hash Algorithm 1) is a widely used hash function designed by the National Security Agency (NSA) of the United States and published as a Federal Information Processing Standard (FIPS) by the National Institute of Standards and Technology (NIST). SHA1 can generate a 160-bit message digest that can be used to verify the integrity and authenticity of data. Due to the irreversibility of SHA1, that is, the original data cannot be deduced from the hash value, it is very suitable for confidentiality enhancement.

[0058] like Figure 1 As shown, in this embodiment, a method for protecting the security of Beidou global data elements includes the following steps:

[0059] Step 1: The user sends a request for a quantum key to the quantum key distribution device and informs the Beidou ground center station of its address information;

[0060] Before starting communication, the quantum key distribution equipment of the user end and the Beidou ground center station must be calibrated and configured, including the light source subsystem, single-photon detector, photoelectric converter and time-to-digital converter. The light source subsystem is used for quantum state preparation and can produce different polarizations; the single-photon detector is used to detect selected single photons; the photoelectric converter is used to convert the detected single photons into electrical pulse signals; the time-to-digital converter converts the time interval into a pulse signal through a pulse signal generator, and then converts the pulse signal into a voltage signal through an integrator, and finally outputs a digital signal.

[0061] Step 2: After receiving the request, the quantum key distribution device generates and distributes the same quantum key to the user terminal and the Beidou ground center station through the quantum channel;

[0062] Quantum key distribution uses the basic principles of quantum mechanics to ensure the security of communications, allowing both communicating parties to generate and share a random and secure key for encryption and decryption of information.

[0063] Specifically, quantum key distribution mainly relies on the transmission and measurement of quantum states. The sender uses a light source to randomly select the ground state of photons, sends these photons to the receiver through a quantum channel, and compares the measurement results through a classical channel to generate a shared key.

[0064] Step 3: The user end uses the quantum key obtained from the quantum key distribution device to encrypt the Beidou data element request and sends the encrypted request to the ground center station;

[0065] Step 4: After receiving the encrypted data, the ground central station uses the corresponding quantum key to decrypt it according to the quantum channel address, and obtains the corresponding Beidou data elements through the Beidou satellite;

[0066] The user end uses the quantum key to encrypt the Beidou data element request into a ciphertext, and then performs a decryption operation. The ground center station decrypts it using the same quantum key. The decryption process is usually the inverse operation of the encryption process.

[0067] Step 5: The ground center station encrypts the corresponding Beidou data elements by combining the quantum key with the AES encryption algorithm, and finally adds it to the outbound broadcast message that is continuously broadcast, and then broadcasts it to the user end via satellite;

[0068] The quantum key is combined with the AES encryption process. Specifically, the quantum key is used as the initial key of the AES encryption algorithm. The AES encryption algorithm sets the number of standard rounds according to the length of the quantum key, and expands the key to a sub-key that is consistent with the number of rounds. When encrypting, the quantum key is first XORed with the data to be transmitted, and then multiple rounds of encryption are performed through the standard round. Decryption is the inverse operation of the encryption operation.

[0069] Step 6: After receiving the outbound signal, the user end uses the quantum key to perform AES decryption and extract the required Beidou data elements.

[0070] Furthermore, the same quantum key is generated and distributed to the user end and the ground central station through the quantum channel, specifically including:

[0071] Step 1: The user end and the ground central station agree in advance to use two orthogonal polarization bases or phase bases;

[0072] Orthogonal polarization bases refer to two mutually perpendicular polarization states, which are perpendicular to each other in space. In quantum mechanics, due to the superposition principle, any polarization state can be superimposed by taking only two mutually orthogonal directions as the basis of vibration directions.

[0073] The phase basis usually refers to the basis related to the phase change of the electric field vector. The phase basis is used to describe the phase distribution characteristics of the light wave and realizes independent encoding of the polarization state of the light by controlling the phase and amplitude.

[0074] In quantum key distribution, orthogonal polarization bases are used to encode and decode the polarization state of photons, while phase bases are used to encode and decode the phase information of photons.

[0075] Step 2: The user terminal randomly selects a group of bits and randomly selects the corresponding polarization basis or phase basis as the basis vector to encode these bits, and sends the encoded quantum state to the ground center station through the quantum channel;

[0076] Polarization encoding can randomly prepare photons of various non-orthogonal polarization states, and can also randomly generate various non-orthogonal polarization state measurement bases, and detect and decode photons of various non-orthogonal polarization states. Phase-based encoding is to encode information on the phase of photons. Phase encoding can accurately compensate for the phase and polarization state of the photon state, thereby restoring the original polarization state of the photon, which can effectively reduce the bit error rate.

[0077] Step 3: After receiving the quantum states, the ground central station randomly selects basis vectors to measure these quantum states;

[0078] Basis vectors are a set of linearly independent and complete vectors that can be used to represent any quantum state. The quantum state is first projected onto the selected basis vectors. The basis vectors must satisfy the conditions of orthogonality and normalization. Through projection measurement, the probability distribution of the observable quantity at a certain specific value is obtained. When the communicating parties obtain consistent information, it means that the selected basis vectors are consistent and the communication has not been eavesdropped.

[0079] Step 4: The user end and the ground central station compare the basis vectors they selected through an open classical communication channel, discard the bits with inconsistent basis vectors, and retain the consistent bits as potential keys;

[0080] Step 5: Perform corresponding error correction and confidentiality enhancement processing on the potential key to form the final key and distribute the quantum key.

[0081] Furthermore, the corresponding error correction and confidentiality enhancement processing specifically includes: performing key error correction through the SECDED error correction algorithm, and then performing confidentiality enhancement on the corrected key through the hash algorithm SHA1.

[0082] The SECDED error correction algorithm can detect and correct single-bit errors and double-bit errors to ensure the integrity of the key. SHA1 can generate a 160-bit message digest, which can be used to verify the integrity and authenticity of the data. Due to the irreversibility of SHA1, the original data cannot be deduced from the hash value, so it is suitable for data confidentiality enhancement.

[0083] Furthermore, quantum key distribution equipment must be installed at both the user end and the Beidou ground center station to establish a quantum channel.

[0084] Furthermore, the encryption process of the AES encryption algorithm includes one initial round and 12 standard rounds.

[0085] Furthermore, the encryption process is specifically as follows: an initial round uses an initial key to perform an XOR operation with plaintext data, and then multiple rounds of encryption are performed through a standard round, where the standard round includes byte replacement, row shift, column confusion, and round key addition operations.

[0086] Byte substitution is to perform nonlinear substitution on each byte through an S-box (substitution table). Row shift is to perform cyclic shift operation on the rows of the state matrix. Column confusion is to perform linear transformation on the columns of the state matrix. Round key addition is to perform XOR operation on the current state and the round key.

[0087] In this embodiment, the round key is expanded from the initial key through the AES key expansion algorithm. The AES key expansion algorithm expands the initial key into a linear array for generating the round key of each round. In this embodiment, 13 128-bit round keys are expanded and generated, and the generation of each round key depends on the previous round key.

[0088] Furthermore, it is finally added to the outbound broadcast message of continuous broadcast. The encrypted Beidou data elements need to be encapsulated in the form of Beidou short messages and then added to the outbound broadcast message. The element data is authenticated and authenticated through the HMAC algorithm to generate an integrity check code.

[0089] HMAC is a message authentication code algorithm based on a hash function, which is mainly used to ensure data integrity and identity authentication. The core idea of ​​HMAC is to combine the key with the data, and then apply the hash function to generate a fixed-length hash value to verify the authenticity and integrity of the data.

[0090] Furthermore, the Beidou data elements are encapsulated in the form of Beidou short messages and added to the outbound broadcast message, specifically including:

[0091] The encapsulated data packet is regarded as the information content of the Beidou short message, and the size of the encapsulated data packet is calculated. If the size of the transmitted information content exceeds the information content capacity limit of the Beidou short message at one time, the payload is split into multiple sub-payloads for transmission; if it is not greater than the capacity limit of the Beidou short message, the encapsulated data packet is added to the outbound broadcast message.

[0092] Furthermore, the payload is split into multiple sub-payloads for sending. The split sub-payloads need to be re-packaged and grouped in the form of Beidou short messages. Each sub-packet after grouping cannot exceed the capacity limit of the Beidou short message. The sub-packet uses the serial number, total number of packets and packet number as the sub-packet identification.

[0093] Furthermore, the corresponding quantum key is used to perform decryption processing according to the quantum channel address, and then the required Beidou data elements are extracted, specifically including: after decryption, judging whether the data packet is a complete data packet or a split sub-data packet through the mark on the data packet. If it is a complete data packet, the integrity of the data packet is directly verified through the integrity check code in the message; otherwise, wait for the data packets of the same sequence to be received and then splice them, and then verify the integrity of the data packet.

[0094] It should be noted that the present application is not limited to the above-mentioned embodiments. The above-mentioned embodiments are only examples, and the embodiments having the same structure as the technical idea and exerting the same effect within the scope of the technical solution of the present application are all included in the technical scope of the present application. In addition, without departing from the scope of the main purpose of the present application, various modifications that can be thought of by those skilled in the art to the embodiments and other methods of combining some of the constituent elements in the embodiments are also included in the scope of the present application.

Claims

1. A method for protecting the security of Beidou global data elements, characterized in that: The following steps are involved: Step 1: The user sends a request for a quantum key to the quantum key distribution device and informs the Beidou ground center station of its address information; Step 2: After receiving the request, the quantum key distribution device generates and distributes the same quantum key to the user terminal and the Beidou ground center station through the quantum channel; Step 3: The user end uses the quantum key obtained from the quantum key distribution device to encrypt the Beidou data element request and sends the encrypted request to the ground center station; Step 4: After receiving the encrypted data, the ground central station uses the corresponding quantum key to decrypt it according to the quantum channel address, and obtains the corresponding Beidou data elements through the Beidou satellite; Step 5: The ground center station encrypts the corresponding Beidou data elements by combining the quantum key with the AES encryption algorithm, and finally adds it to the outbound broadcast message that is continuously broadcast, and then broadcasts it to the user end via satellite; Step 6: After receiving the outbound signal, the user end uses the quantum key to perform AES decryption and extract the required Beidou data elements.

2. A method for protecting the security of Beidou global data elements according to claim 1, characterized in that: The generating and distributing the same quantum key to the user terminal and the ground central station through the quantum channel specifically includes: Step 1: The user end and the ground central station agree in advance to use two orthogonal polarization bases or phase bases; Step 2: The user terminal randomly selects a group of bits and randomly selects the corresponding polarization basis or phase basis as the basis vector to encode these bits, and sends the encoded quantum state to the ground center station through the quantum channel; Step 3: After receiving the quantum states, the ground central station randomly selects basis vectors to measure these quantum states; Step 4: The user end and the ground central station compare the basis vectors they selected through an open classical communication channel, discard the bits with inconsistent basis vectors, and retain the consistent bits as potential keys; Step 5: Perform corresponding error correction and confidentiality enhancement processing on the potential key to form the final key and distribute the quantum key.

3. A method for protecting the security of Beidou global data elements according to claim 2, characterized in that: The corresponding error correction and confidentiality enhancement processing specifically includes: performing key error correction by using the SECDED error correction algorithm, and then performing confidentiality enhancement on the corrected key by using the hash algorithm SHA1.

4. The method for protecting the security of Beidou global data elements according to claim 1, characterized in that: The quantum key distribution device must be installed at both the user end and the Beidou ground center station to establish a quantum channel.

5. The method for protecting the security of Beidou global data elements according to claim 1, characterized in that: The encryption process of the AES encryption algorithm includes an initial round and several standard rounds.

6. A method for protecting the security of Beidou global data elements according to claim 5, characterized in that: The encryption process is specifically as follows: using the initial key to perform an XOR operation with the plaintext data through the initial round, and then performing multiple rounds of encryption through the standard round, wherein the standard round includes byte replacement, row shift, column confusion and round key addition operations.

7. The method for protecting the security of Beidou global data elements according to claim 1, characterized in that: The finally adding it to the outbound broadcast message of continuous broadcasting needs to first encapsulate the encrypted Beidou data elements in the form of Beidou short messages and then add them to the outbound broadcast message, and perform integrity authentication and identity authentication on the element data through the HMAC algorithm to generate an integrity check code.

8. A method for protecting the security of Beidou global data elements according to claim 7, characterized in that: The Beidou data elements are encapsulated in the form of Beidou short messages and added to the outbound broadcast message, specifically including: The encapsulated data packet is regarded as the information content of the Beidou short message, and the size of the encapsulated data packet is calculated. If the size of the transmitted information content exceeds the information content capacity limit of the Beidou short message at one time, the payload is split into multiple sub-payloads for transmission; if it is not greater than the capacity limit of the Beidou short message, the encapsulated data packet is added to the outbound broadcast message.

9. A method for protecting the security of Beidou global data elements according to claim 8, characterized in that: The payload is split into multiple sub-payloads for sending. The split sub-payloads need to be re-packaged and grouped in the form of Beidou short messages. Each small packet after grouping cannot exceed the capacity limit of the Beidou short message. The small packet uses the serial number, the total number of packets and the packet number as the sub-packet identification.

10. A method for protecting the security of Beidou global data elements according to claim 1, characterized in that: The method uses the corresponding quantum key to perform decryption processing according to the quantum channel address, and then extracts the required Beidou data elements, specifically including: after decryption, judging whether the data packet is a complete data packet or a split sub-data packet through the mark on the data packet; if it is a complete data packet, directly verifying the integrity of the data packet through the integrity check code in the message; otherwise, waiting for the data packets of the same sequence to be received and then splicing them, and then verifying the integrity of the data packet.

Images