Encryption method based on dynamic coupling image lattice

Abstract

The invention relates to the technical field of communication security, and particularly provides an encryption method based on a dynamic coupling image lattice, comprising the following steps: S1, acquiring to-be-encrypted constellation diagram data, and taking the constellation diagram data as plaintext data; s2, carrying out DNA coding on the plaintext data, then carrying out arithmetic operation, and then carrying out DNA anti-coding to complete data disturbance encryption; rules of DNA coding, operation and DNA anti-coding are determined through a preset method. The preset method comprises the following steps: S21, acquiring a key sequence, and dividing the key sequence; s22, generating a first intermediate one-dimensional pseudo-random sequence by using a first chaotic mapping model; s23, performing dynamic iteration on the first intermediate one-dimensional pseudo-random sequence by using a one-dimensional coupling mapping lattice model fused by a second chaotic mapping model to obtain a second intermediate one-dimensional pseudo-random sequence; and S24, determining the rules of DNA coding, operation and DNA anti-coding through the second intermediate one-dimensional pseudorandom sequence. The method is high in sequence randomness and high in communication security.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of communication security technology, in particular to an encryption method based on a dynamic coupling mapping grid. The present application can be used for secure communication services, especially for constellation diagram disturbance encryption in OFDM modulation systems. BACKGROUND

[0002] In recent years, with the acceleration of digital transformation and upgrading of various industries, more information optical transmission and access security, network penetration threats and challenges are faced after entering the cloud era. There are threats such as eavesdropping and interference in communication transmission; how to protect the transmission security of access network communication data from the communication system, and enhance the information transmission confidentiality is particularly important for solving information security. Therefore, the research on information transmission confidentiality and other physical layer security enhancement technologies has become one of the important problems to be solved in broadband access network, and how to improve the information transmission confidentiality of broadband access network has become one of the hot topics of common concern in the current international academic and industrial circles.

[0003] OFDM (Orthogonal Frequency Division Multiplexing) is a kind of efficient multicarrier modulation technology, which is widely used in wireless communication; it can divide high-speed data stream into multiple low-speed subcarriers for parallel transmission, and the symbol point coordinates (I / Q values) corresponding to each subcarrier after modulation in the modulation process are constellation diagram data, which is used to represent the mapping of digital bits on the complex plane and carry specific transmission information. The key of communication security technology is to encrypt the constellation diagram data.

[0004] Common encryption methods include application layer encryption, optical chaos encryption, quantum noise stream encryption, and digital chaos encryption. Application layer encryption generally adds respective identity authentication and encryption standards in the five layers of the application layer of the open system interconnection reference seven-layer model. The technology is very mature, and has been applied in PON standards. It is particularly convenient for secure communication in computer operating systems. Common national encryption algorithms and commercial encryption algorithms belong to application layer encryption algorithms. However, this encryption method has the problems of limited key space and complex management, cannot provide security protection for control information and headers, and relies on the computational complexity of algorithm cracking to provide network security protection, which has the problems of high cost, large delay, complex configuration and the like. It cannot meet the needs of high-speed communication. Optical chaos security uses optical chaos to encrypt optical signals and realizes information decryption through chaos synchronization. This encryption method has high random physical entropy source and high communication security, and hardware encryption does not introduce DSP delay. However, additional equipment needs to be introduced, which increases the cost, and the chaos bandwidth is limited, and synchronization is difficult at long distances. Quantum noise stream encryption has good compatibility with existing systems. It uses the uncertainty of the signal state of a laser in measurement to cover the subdivided signal. Quantum noise originates from the quantization of the optical field, and the mechanical quantity of the field cannot be measured with arbitrary precision. However, additional redundancy is generated, resulting in a signal rate that is much higher than the plaintext rate, which sacrifices part of the frequency spectrum utilization rate. The security is based on digital scrambling and needs to be enhanced. Digital chaos encryption uses the nonlinearity, randomness and initial value sensitivity of chaos to generate a pseudo-random sequence for data encryption. It does not need to introduce additional equipment and has good compatibility with existing communication networks. However, the generation of a chaotic pseudo-random sequence needs to introduce additional DSP delay, and the communication real-time performance is low. The key space of a separate digital chaos encryption method is also limited, and is limited by the precision of floating-point numbers, which can easily cause chaos dynamics degradation. The existing high-dimensional chaos mapping model and high-dimensional coupled image lattice mapping model have high computational complexity, especially the calculation of trigonometric functions needs complex high-precision floating-point number operations, and the operation efficiency is extremely low.

[0005] However, the coupling strength factor of the low-dimensional coupled image lattice model is constant, which brings the problems of narrow parameter space, prominent local chaotic behavior and chaos degradation, so that the low-dimensional chaos mapping model and the low-dimensional coupled image lattice mapping model have insufficient chaos strength, weak sequence randomness, predictable encryption results and low security.

[0006] In summary, due to the constant coupling strength factor, the sequence randomness of the existing encryption method is weak, and the communication security is low. SUMMARY

[0007] The present application aims at the deficiencies in the prior art, and provides an encryption method based on a dynamic coupling image lattice to solve the problems of weak randomness of the existing encryption method sequence and low communication security due to constant coupling strength factor in the prior art.

[0008] The technical concept of the present application is as follows: The first mapping function of the second chaotic mapping model (such as a two-dimensional HENON mapping) is introduced as a local nonlinear mapping function into the one-dimensional coupling image lattice model, and the state of each lattice point in the one-dimensional coupling image lattice model is determined not only by the evolution function itself but also by the strong nonlinear iteration of the HENON mapping, so that strong nonlinear disturbance is introduced in each iteration, and the local behavior of each lattice point has higher complexity and sensitivity; due to the adjacent coupling mechanism, the state of the lattice point is also affected by the adjacent lattice points, that is, the states of these adjacent lattice points after nonlinear mapping also participate in the evolution of the current lattice point, so as to realize nonlinear cross interference and diffusion of the states between the lattice points and improve the disturbance ability of the whole system in the spatial dimension.

[0009] The second mapping function of the second chaotic mapping model is dynamically introduced as a coupling strength factor into the one-dimensional coupling image lattice model, and its value changes continuously with the iteration process of the HENON mapping, so as to realize dynamic adjustment of the coupling strength in time (each iteration) and space (each lattice point). In this way, on the one hand, the parameter space is expanded, the fixed coupling factor can only adjust the coupling degree of the image lattice in a small range, and it is easy to fall into local stable state or periodic behavior, while the dynamic and continuous change breaks this limitation, so that the system explores a wider parameter region; on the other hand, non-stationary dynamic evolution is realized, the coupling strength of different lattice points is not the same, which breaks the symmetry and stability of the global structure, so that the system is always in a non-stationary and non-periodic chaotic state; on the other hand, the anti-degradation ability is enhanced, and the floating point precision error or the loop iteration may cause the chaotic system to degenerate into a finite state set, while the dynamic coupling factor effectively avoids the system from falling into a stable orbit, so as to maintain continuous and highly chaotic evolution.

[0010] The fusion strategy of the present application not only significantly improves the diffusion and unpredictability of the generated pseudo-random sequence, but also makes the constellation data disturbance more complex, diverse and difficult to restore, effectively resisting statistical analysis, reconstruction attacks and other threats, so as to realize the high security goal in physical layer communication encryption.

[0011] To achieve the above object, the technical scheme adopted by the present application is as follows: The present application provides an encryption method based on a dynamic coupling image lattice, which comprises the following steps: S1, obtaining the constellation data to be encrypted, and taking the constellation data as plaintext data; S2 encodes the plaintext data using DNA, performs computational operations, and then performs DNA decoding to complete the data scrambling and encryption, obtaining the ciphertext data of the constellation diagram. The rules for DNA encoding, computational operations, and DNA decoding are determined by a preset method.

[0012] The default method is as follows: S21, Obtain the key sequence and divide the key sequence to obtain the encryption parameters; S22, use the first chaotic mapping model to generate the first intermediate one-dimensional pseudo-random sequence; the initial value and chaotic control parameters of the first chaotic mapping model are determined by the encryption parameters; S23, using the one-dimensional coupled mapping lattice model fused by the second chaotic mapping model, the first intermediate one-dimensional pseudo-random sequence is dynamically iterated to obtain the second intermediate one-dimensional pseudo-random sequence; the initial value and chaotic control parameters of the second chaotic mapping model, the time iteration parameters and coupling coefficient parameters of the one-dimensional coupled mapping lattice model are determined by the encryption parameters; S24 determines the rules for DNA coding, computational operations, and DNA decoding through the second intermediate one-dimensional pseudo-random sequence.

[0013] Furthermore, in S23, the first intermediate one-dimensional pseudo-random sequence is input into the one-dimensional coupled mapping lattice model, and the one-dimensional coupled mapping lattice model outputs the second intermediate one-dimensional pseudo-random sequence.

[0014] Furthermore, the coupling mapping function in the one-dimensional coupled mapping lattice model is the first mapping function in the second chaotic mapping model.

[0015] Furthermore, the coupling strength factor in the one-dimensional coupled mapping lattice model is the second mapping function in the second chaotic mapping model.

[0016] Furthermore, the expression for the second chaotic mapping model, the two-dimensional HENON chaotic mapping model, is as follows: Where, n For sequence dimension values, , It is the current state value. These are the chaos control parameters for the first mapping function. These are the chaos control parameters for the second mapping function. , The results are the first mapping function and the second mapping function.

[0017] Furthermore, the expression for the one-dimensional coupled mapping lattice model is: in, to couple the intensity factor, i.e., the second mapping function, 、 、 are the coupling mapping functions corresponding to the sequence dimension values n-1, n-2, n, respectively, i.e., the first mapping function.

[0018] Further, the periodic boundary constraint condition of the one-dimensional coupled map lattice model is: wherein, is the sequence index value, and L is the total length of the index, i.e., the total number of lattices.

[0019] Further, the first chaotic mapping model is a one-dimensional TENT chaotic mapping model, and the expression is: wherein, is the sequence index value, is the current state value, is the chaotic control parameter of the first chaotic mapping model.

[0020] Further, in S23, a plurality of one-dimensional coupled map lattice models are used for parallel processing.

[0021] Further, the plaintext data is constellation data output by an OFDM modulation system.

[0022] Compared with the prior art, the application has the following beneficial effects: (1) The second chaotic mapping model is used to fuse the one-dimensional coupled map lattice model to dynamically iterate the first intermediate one-dimensional pseudo-random sequence, so as to obtain the second intermediate one-dimensional pseudo-random sequence, which is used for data scrambling encryption. The strong nonlinear disturbance of the local state of each lattice point is realized, and the cross influence between adjacent lattice points is combined to construct a dynamic system with stronger spatial coupling and more complex state evolution; and the continuous change of the coupling strength between lattice points in time and space effectively breaks through the parameter space narrowness and system dynamics degradation problem caused by fixed coupling parameters. This mechanism breaks the global symmetry structure, promotes the system to maintain a non-stationary and non-periodic chaotic state, and has strong anti-degradation ability. The pseudo-random sequence generated by the fused one-dimensional coupled map lattice model is superior in diffusion, sensitivity and unpredictability, significantly enhances the scrambling effect on the constellation data, makes it more complex, diverse and difficult to reverse, and effectively resists constellation analysis, statistical modeling and other attack methods, thereby ensuring the high security of the physical layer communication system.

[0023] (2) The application introduces a spatiotemporal chaotic system to enhance the chaotic characteristics of the encryption system in both time and space dimensions, thereby significantly improving the security of communication encryption. In the time dimension, a first chaotic mapping model is used to generate a highly sensitive and unpredictable pseudo-random sequence, making the system highly responsive to small changes in initial conditions, thereby ensuring the non-reproducibility and anti-exhaustion ability of the encryption process. In the spatial dimension, the mapping function of a second chaotic mapping model is dynamically embedded into the coupled mapping lattice model. This not only enhances the evolution complexity of each lattice point through nonlinear mapping, but also realizes the real-time change of perturbation between lattice points through dynamic coupling strength, forming a strong diffusion effect in space. The combination of the two forms a spatiotemporal coupled dynamic system, effectively preventing the exposure of regularity caused by chaotic degradation and fixed parameters, greatly improving the complexity of the disturbance sequence and the non-analyzability of the encrypted data, thereby realizing a high-strength, attack-resistant, and low-latency communication encryption scheme at the physical layer. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 A schematic diagram of an encryption method based on a dynamic coupled mapping lattice provided by the application; Figure 2 A schematic diagram of the process of encrypting plaintext data by an encryption method based on a dynamic coupled mapping lattice provided by the application; Figure 3 A schematic diagram of a preset method of an encryption method based on a dynamic coupled mapping lattice provided by the application; Figure 4 A schematic diagram of the parallel operation of the fusion module. DETAILED DESCRIPTION

[0025] To make the implementation process of the application clearer, the following will be described in detail with reference to the accompanying drawings.

[0026] Example 1: The application provides an encryption method based on a dynamic coupled mapping lattice, which includes the following steps, as shown in Figure 1 S1, obtaining constellation data to be encrypted, taking the constellation data as plaintext data; The constellation data of the application is the constellation data output by an OFDM modulation system, the system input data is the coordinate data output by constellation IQ modulation, and the length of the encrypted data is N 8-bit bytes each time. The constellation data is represented by complex symbols, each symbol corresponds to a pair of real coordinate (I, Q), I represents the in-phase component, and Q represents the quadrature component. Through normalization or quantization processing, each coordinate value is converted into an integer between 0 and 255 (i.e., 8-bit bytes), and then converted into binary representation, and then converted into the corresponding base sequence through DNA encoding.

[0027] ​S2, DNA encoding is performed on the plaintext data, then DNA operation is performed, and then DNA decoding is performed, completing data scrambling encryption to obtain ciphertext data of the constellation data; the rules of DNA encoding, operation and DNA decoding are determined by a preset method.

[0028] DNA encoding is a coding method that converts information into DNA sequences, commonly used in data storage and information security fields. DNA has four bases: adenine (A), cytosine (C), guanine (G) and thymine (T), corresponding to 2 bits of binary data. As long as they are one-to-one corresponding according to a certain rule, DNA encoding can be performed. For example, adenine (A) corresponds to 00, cytosine (C) corresponds to 01, guanine (G) corresponds to 10, and thymine (T) corresponds to 11. 00 and 11 are complementary, 01 and 10 are complementary, adenine (A) and thymine (T) are paired, and cytosine (C) and guanine (G) are paired, which can establish corresponding coding constraint rules. According to the above constraint rules, there are 8 common DNA encoding rules. The arrangement of the 8 rules is fixed, and the rule number corresponding to each arrangement is random. In this way, only the rule number is determined to determine the corresponding encoding, which effectively improves the unpredictability of the encryption method. As shown in Table 1, for example, the decimal number 120 is encoded into binary 01111000. For example, using rule 1, the corresponding DNA base is CTGA.

[0029] Table 1: DNA encoding table Rules 1 2 3 4 5 6 7 8 00 A A G C G C T T 01 C G T T A A C G 10 G C A A T T G C 11 T T C G C G A A DNA decoding is to establish a corresponding relationship between the four bases of 2 bits of binary data DNA according to a certain rule. According to the DNA base pairing and binary complementary constraint rules, there are 8 common DNA decoding rules. Similar to the encoding rule, the corresponding rule number needs to be determined to determine the corresponding decoding, which improves the unpredictability and better encryption effect. As shown in Table 2, for example, using rule 1 to perform DNA decoding on bases ACGT, the corresponding binary number is 00011011, which is converted into a decimal number 27.

[0030] Table 2: DNA decoding table Rules 1 2 3 4 5 6 7 8 A 00 00 01 10 01 10 11 11 C 01 10 00 00 11 11 01 10 G 10 01 11 11 00 00 10 01 T 11 11 10 01 10 01 00 00 In order to increase the complexity of the encryption algorithm, XOR operation is performed on the bases after DNA encoding. The DNA operation rule is defined as shown in Table 3, for example, the result of XOR operation between base A and base A is A, and the result of XOR operation between base G and base C is T. At the same time, the bases A, T, C and G are numbered as 1, 2, 3 and 4, which are one-to-one corresponding to the XOR operation rule.

[0031] Table 3: XOR operation table XOR A T C G A A T C G T T A G C C C G A T G G C T A The specific encryption steps of the present application are as shown in the following table: Figure 2 The DNA encoding, operation and DNA decoding rules are determined by a preset method. The input plaintext data is first DNA encoded, then DNA operated and then DNA decoded for data scrambling encryption. For example, the DNA encoding rule is 5, the operation rule is XOR operation with thymine (T), the DNA decoding rule is 3, and the input data is 120; first, the DNA encoding rule 5 is used for encoding, the output base is ACTG, then XOR operation with T is performed, the output base is TGAC, and then the DNA decoding rule 3 is used for decoding, the final output binary number is 10110100, so the input plaintext data 120 is encrypted and the final output ciphertext data is 180.

[0032] The DNA encoding, DNA operation and DNA decoding processing of the constellation data can significantly improve the encryption security of the data. Specifically, the traditional binary number is converted into a sequence composed of base symbols by DNA encoding, a variety of mapping rules are introduced in the encoding process, so that the same original data can correspond to different DNA sequences; that is, a higher-dimensional data representation method is introduced at the encoding level, the information is nonlinearly expanded in the conversion process, the analyzable structure of the original data is broken, and the difficulty of analysis and restoration by attackers is increased. DNA operation further disturbs the data at the DNA sequence level, combined with dynamic rule selection driven by chaotic sequence, can effectively diffuse the local features of the original constellation data, so that the same data has completely different encoding results under different keys, and the unpredictability of the system is enhanced. The disturbed DNA sequence is restored to a new value by DNA decoding to complete the encryption process. The whole process has high nonlinearity and complexity, fully utilizes the advantages of DNA computing in information diffusion and confusion, effectively breaks the original distribution rule of the constellation data, resists constellation analysis, known plaintext and other attack methods, so as to realize stronger data concealment and security at the physical layer.

[0033] Preferably, in use, multi-channel DNA encoding, operation, DNA decoding and parallel encryption operation are adopted; the DNA encoding and decoding process is simple and efficient, suitable for parallel computing, especially suitable for encryption requirements in large-capacity high-speed communication. As an encryption intermediate layer of the constellation data, DNA encoding not only improves the complexity and dynamics of the system, but also shows significant advantages in security, anti-analysis and real-time performance.

[0034] The preset method is as follows, as shown in the following table: Figure 3 S21, obtaining a key sequence, and dividing the key sequence to obtain an encryption parameter; ​The key sequence in the application is mainly a dynamic key, which is generated by the transmitting end according to a key seed, or the same initial parameters are distributed to the transmitting end by a third-party security module or a preset mechanism before communication starts, and the dynamic key is distributed before the transmission of a data packet. Each data packet is composed of N data, and the data packet is encrypted in parallel using a separate dynamic key.

[0035] The key sequence is obtained, and encryption parameter preprocessing is performed, that is, the key sequence is divided. The sequence contains, in order: the time iteration number parameter m (occupying 1 byte) of the one-dimensional coupled map model, the initial value of the random sequence of the first chaotic mapping model (occupying 1 byte) and the chaotic control parameter μ (occupying 2 bytes), the initial value of the second chaotic mapping (each occupying 1 byte, a total of 2 bytes) and the chaotic control parameters a and b (each occupying 2 bytes, a total of 4 bytes); the total key sequence is 10 bytes, which is used as the input parameter of the first intermediate one-dimensional pseudo-random sequence generation module.

[0036] S22, a first intermediate one-dimensional pseudo-random sequence is generated using a first chaotic mapping model; the initial value and the chaotic control parameter of the first chaotic mapping model are determined by the encryption parameter; The first chaotic mapping model is a one-dimensional TENT chaotic mapping model, and the expression is: wherein, is the sequence index value, is the current state, and the value range is , is the chaotic control parameter of the first chaotic mapping model, and the value range is . According to the initial value of the random sequence of the first chaotic mapping model and the chaotic control parameter μ obtained in S21, a one-dimensional pseudo-random sequence is generated using the one-dimensional TENT chaotic mapping model, and data normalization preprocessing is performed, that is, the first intermediate one-dimensional pseudo-random sequence is obtained.

[0037] ​​​The TENT map has good chaotic characteristics, strong initial value sensitivity, simple structure and high computational efficiency, and is particularly suitable for large-scale parallel encryption requirements in high-speed communication scenarios. By setting the initial value and chaotic control parameters, the model generates a highly unpredictable pseudo-random sequence in the iteration process, which is used to drive the selection and switching of DNA encoding and DNA operation rules, ensuring that the disturbance mode in the encryption process changes dynamically with the sequence, thereby greatly enhancing the randomness and diversity of the encryption result and avoiding the repeatability and analyzability of the encryption mode under fixed rules. The first intermediate one-dimensional pseudo-random sequence not only reflects the sensitive diffusion ability of the initial key in the system, but also guides the encoding transformation path of information at the DNA level, which is a key control variable that connects the original constellation data and subsequent dynamic encryption processing. It reflects the dynamic disturbance control information driven by the key and is the basis for the "homogeneous heterogeneous" transformation of constellation data in the entire encryption system, effectively improving the resistance of the system to statistical analysis, reconstruction attacks and other means, and significantly enhancing the security of physical layer encryption.

[0038] Specifically, the random sequence initial value obtained in S21 is normalized to and the chaotic control parameters are normalized to to ensure that the input constraints of the TENT map are met, so that the chaotic system works stably and has good ergodicity, which plays a role in ensuring that the chaotic system operates within the allowed range of the mathematical model and has stable chaotic evolution characteristics; then, based on the normalized initial value and control parameters, the first intermediate one-dimensional pseudo-random sequence is generated by iterating the TENT mapping formula, and the sequence itself is a floating-point number sequence; the sequence is normalized again to the integer interval [0, 255] to adapt to the byte-level data structure required in subsequent DNA encoding and other operations, that is, the discrete floating-point pseudo-random number is converted to an integer form to generate a pseudo-random sequence : where x is a discrete floating-point pseudo-random number, which is convenient for use in actual communication and encryption applications.

[0039] In S23, the first intermediate one-dimensional pseudo-random sequence is dynamically iterated using a one-dimensional coupled map model fused by a second chaotic mapping model to obtain a second intermediate one-dimensional pseudo-random sequence; the initial value and chaotic control parameters of the second chaotic mapping model, the time iteration parameter and the coupling coefficient parameter of the one-dimensional coupled map model are determined by the encryption parameters; The first intermediate one-dimensional pseudo-random sequence is input into the one-dimensional coupled map model, and the one-dimensional coupled map model outputs the second intermediate one-dimensional pseudo-random sequence; the normalized first intermediate one-dimensional pseudo-random sequence is input into the second chaotic mapping model.

[0040] The expression of the second chaotic mapping model is a two-dimensional HENON chaotic mapping model: wherein n is a sequence dimension value, , is a current state value, and the value range is ; is a chaos control parameter of the first mapping function, is a chaos control parameter of the second mapping function, , is a result of the first mapping function and the second mapping function, controls a nonlinearity intensity and determines a chaos degree of the model, affects energy dissipation of the model, and the value range is , . The parameter a controls the nonlinearity intensity and is a key to determine whether the system enters a chaos region, and is set in the range of [0, 1.4], especially when close to 1.4, the system can be in a typical chaos interval, with extremely high initial value sensitivity and trajectory unpredictability; and the parameter b=0.3 is an energy dissipation factor commonly used in the classic HENON mapping, which can ensure that the system maintains moderate stability while continuously in chaos, avoiding the system into a state of excessive divergence or premature convergence. Such parameter setting not only can generate pseudo-random sequences with complex structure and extensive distribution, but also can enhance the resistance of the mapping system to floating-point errors and numerical perturbations, thereby reducing the chaos degradation phenomenon and ensuring the diversity and uniqueness of the disturbed path in the encryption process. By keeping the HENON system running in a wide and stable chaos interval, the unpredictability of the pseudo-random sequence and the anti-attack ability of the system are significantly improved, providing strong security protection for constellation data encryption.

[0041] The parameter a controls the nonlinearity of the system, determines the chaos degree, and b affects the energy dissipation characteristics of the system, thereby adjusting the stability and persistence of the chaotic behavior. The HENON mapping can stably generate chaotic trajectories with high complexity, high sensitivity and non-periodicity in a wide parameter space, and has good initial value sensitivity and ergodicity. Compared with other complex mapping functions, the HENON mapping only relies on basic algebraic operations and does not involve high-precision floating-point calculations such as trigonometric functions, so it has low operation overhead and high efficiency in hardware implementation, and is very suitable for encryption systems in high-speed communication environments. In this scheme, the first mapping function of the HENON mapping is introduced as a local nonlinear disturbance source of the coupled mapping cell model, which improves the dynamic complexity of each cell, and the second mapping function is used as a dynamic coupling strength control factor to guide the system to generate non-stationary and asymmetric coupling disturbances in time and space dimensions, breaking the potential structural patterns in constellation encryption. The dual advantages of high chaos and high efficiency not only improve the security and anti-statistical analysis capability of the encryption system, but also significantly improve the diffusion and unpredictability of the pseudo-random sequence, making it an ideal chaotic core for building high-performance physical layer encryption systems.

[0042] The first mapping function in the second chaotic mapping model is used as the coupling mapping function in the one-dimensional coupled mapping cell model, i.e., the local nonlinear mapping function; the second mapping function in the second chaotic mapping model is the coupling strength factor in the one-dimensional coupled mapping cell model. The one-dimensional coupled mapping cell model is a mathematical model used to describe the complex dynamic behavior of a closed system. It divides the overall sequence into multiple independent regions, i.e., cells or lattices, and applies a nonlinear mapping function to each cell while defining the coupling mechanism between cells, allowing adjacent cells to influence and disturb each other, forming an evolution system with spatiotemporal chaotic characteristics. Using a chaotic mapping function as a local mapping function is suitable for building secure and complex encryption disturbance systems due to its high nonlinearity, initial value sensitivity, long-term unpredictability and pseudo-randomness. Compared with high-dimensional chaotic systems, the one-dimensional coupled mapping cell model has higher computational efficiency and simpler structure, making it easier to implement in parallel in hardware, which is very suitable for the needs of high-speed and low-latency communication systems. In this application, the model is applied to the encryption process of constellation data, introducing a cell structure to each modulation symbol to make the disturbance behavior not only controlled by its own state but also disturbed by adjacent symbols, forming a diffusion and disturbance effect across data points; further combined with a dynamic coupling strength control mechanism, the disturbance path changes constantly in time and space, greatly improving the complexity of the disturbance result and the irreversibility of the data, effectively enhancing the anti-analysis capability and security strength of constellation encryption.

[0043] The mathematical expression of the unfused one-dimensional coupled mapping cell is defined as follows: wherein, is a sequence dimension value, is a sequence time dimension value, is a current state value, is a coupling strength factor, and the value range is ; is a coupling mapping function, i.e., a local nonlinear mapping function. The coupling strength factor controls the weight distribution of state information between the current grid point and the adjacent grid point, and the value is in the interval , which can ensure that the sum of the weights is 1, i.e., maintaining the evolution of the system state within a bounded range, avoiding numerical divergence or energy non-conservation phenomena; when ε = 0, it means complete uncoupling, and each grid point evolves independently; when ε = 1, it means complete dependence on adjacent grid points, and the local state no longer plays a dominant role. This range can flexibly adjust the balance between local nonlinearity and global diffusion of the system. From the perspective of encryption application, ε is in the floating point interval , which can introduce rich disturbance patterns and chaotic paths by dynamically changing, enhancing the diversity and initial value sensitivity of the pseudo-random sequence, thereby improving the unpredictability and anti-statistical analysis ability of the encryption system against attackers. Therefore, this numerical range not only guarantees the numerical stability and physical realizability of the model, but also brings stronger dynamic complexity and security to the encryption process.

[0044] In the one-dimensional coupled map lattice model, the local nonlinear mapping function and the coupling strength factor are the key factors that determine the chaotic behavior and dynamic complexity of the system. The local nonlinear mapping function is used to control the state update process of each grid point. The higher the nonlinearity and the more complex the dynamic characteristics, the more chaotic and unpredictable the generated state sequence will be. The coupling strength factor is used to adjust the degree of interference between each grid point and its adjacent grid points, which determines the diffusion speed and coupling strength of information in the entire grid system. When the coupling factor is a fixed value, the system is prone to local stability or periodic behavior, limiting the chaotic diffusion range. By introducing a dynamically changing coupling strength, the global symmetry structure can be effectively broken, and the system can maintain non-stationary chaotic evolution in both time and space dimensions. The synergistic effect of the local mapping function and the coupling strength will directly affect the generated second intermediate one-dimensional pseudo-random sequence, making it exhibit higher complexity and unpredictability in terms of numerical distribution, correlation, randomness, etc., thereby significantly enhancing the disturbance strength and diffusion ability in the constellation data encryption process. Such pseudo-random sequences used to control DNA encoding, operation path, and constellation disturbance operations can not only enhance the dynamic diversity and key dependence of the encryption results, but also effectively resist statistical analysis, reconstruction guessing, and other attack methods, comprehensively improving the security and robustness of the constellation encryption system.

[0045] The periodic boundary constraint condition of the one-dimensional coupled map lattice model is: wherein, is the sequence dimension value, is the index of one-dimensional coupled mapping lattice mapping; L is the total length of the index, that is, the total number of lattices. That is, the left adjacent lattice of the first lattice is the last lattice, and the right adjacent lattice of the last lattice is the first lattice. The core role of the constraint is to eliminate the boundary effect, so that all lattice points have symmetry and equivalence in space, and ensure that each lattice point has two effective adjacent coupling objects, so that the coupling structure realizes the complete closed loop state information diffusion and disturbance in the spatial dimension. This end-to-end topology enhances the overall connectivity and chaotic diffusion capacity of the system, avoids the lack of disturbance intensity or regularity leakage caused by the lack of coupling of edge lattice points, and thus reduces the risk of overall encryption effect. For constellation data encryption, the periodic boundary condition can ensure that all modulation symbols are in an equal interference environment during the disturbance process, so that the disturbance effect is uniformly distributed in the entire data sequence, further improving the complexity of the pseudo-random sequence and the unpredictability of the disturbance path, effectively enhancing the anti-attack ability of the encryption system when facing statistical attacks, boundary tracking and other analysis methods, and thus improving the security and robustness of the physical layer constellation encryption.

[0046] The expression of the one-dimensional coupled mapping lattice model after fusion is: wherein, is the coupling strength factor, that is, the second mapping function, , , and are the coupling mapping functions corresponding to the sequence dimension values n-1, n-2 and n, that is, the coupling mapping functions corresponding to the middle lattice point and the left and right adjacent two lattice points, that is, the first mapping function.

[0047] The first mapping function of the second chaotic mapping model is introduced into the one-dimensional coupled mapping lattice model as a local nonlinear mapping function, which fully utilizes its high nonlinearity, initial value sensitivity and high system complexity. It presents stable and strong chaotic behavior, which is used to drive the state evolution of each lattice point in the one-dimensional coupled mapping lattice model. The lattice point is not only updated according to its state at the previous time, but also driven by the nonlinear output of the HENON mapping, which significantly improves the complexity and uncertainty of the lattice point behavior. At the same time, the one-dimensional coupled mapping lattice model itself has a neighboring coupling mechanism, and the fusion term of the state of the adjacent lattice points is included in the evolution formula, that is, the state of each lattice point depends not only on the local mapping function, but also on the disturbance of the surrounding lattice points after nonlinear mapping, realizing the nonlinear cross-influence and diffusion between lattice points and enhancing the spatial chaotic characteristics of the system. The dynamic output of the second mapping function in the HENON mapping is introduced as the coupling strength factor in the one-dimensional coupled mapping lattice model, so that the coupling strength is no longer a static constant, but changes with time iteration and lattice position in real time, thereby breaking the local stability and periodic degradation problem caused by the fixed coupling strength in the traditional one-dimensional coupled mapping lattice model. Through this dynamic coupling mechanism, the system can evolve in a wider parameter space, avoiding falling into stable orbits or limited state sets, while the dynamic inconsistency of the coupling degree of each lattice point breaks the symmetry of the global structure, so that the entire mapping lattice system is always in a non-periodic, non-stationary, high-dimensional chaotic state in space and time. This fusion strategy not only enhances the dynamics of the chaotic system itself, but also makes the generated pseudo-random sequence have higher unpredictability and disturbance ability, further enhancing the diffusion, security and attack resistance of the constellation data encryption process.

[0048] Preferably, in S23, a plurality of fused one-dimensional coupled mapping lattice models can be run in parallel. The multi-channel coupled mapping lattice fusion sub-module runs in parallel to perform coupling operation on the plurality of first intermediate one-dimensional pseudo-random sequences generated in S22; wherein the operation unit includes a two-dimensional HENON chaotic mapping module and a one-dimensional coupled mapping lattice model, and the input is the sequence of the adjacent three lattices, and the output is the sequence of the next time intermediate lattice, and the actual module internal architecture is as follows Figure 4 as shown; DNA coding, operation and reverse coding are a sequential process, which is packaged into each independent module, and then multiple modules are run in parallel.

[0049] In S24, the rules of DNA coding, operation and DNA reverse coding are determined by the second intermediate one-dimensional pseudo-random sequence.

[0050] The following is an example of a one-dimensional pseudo-random sequence of 53, which corresponds to the binary number 00110101, and the split DNA coding sequence is 001, the XOR operation sequence is 10, and the coding rule is 101; When using, the DNA coding module includes a lookup table unit, which internally stores an 8*4 encoding table (as shown in Table 1), and the content of the corresponding encoding table is read out according to the sequence 3 bits rule to perform the encoding operation, the 3 bits data range is 0-7, corresponding to 8 encoding rules, and the sequence 001 corresponds to the encoding rule 2, then the second set of rules is used for DNA coding. The DNA XOR operation module performs XOR operation with the corresponding base sequence according to the sequence 2 bits rule, and the 2 bits data range is 0-3, corresponding to 4 base sequences, and the sequence 10 corresponds to the base sequence 3, then XOR operation is performed with the third base "C". The DNA decoding module includes a lookup table unit, which internally stores an 8*4 encoding table, and the content of the corresponding encoding table is read out according to the sequence 3 bits rule to perform the decoding operation, the 3 bits data range is 0-7, corresponding to 8 decoding rules, and the sequence 101 corresponds to the decoding rule 6, then the sixth set of rules is used for DNA decoding; The ciphertext data is generated, and the input constellation IQ modulation coordinate data encryption operation is completed, and the constellation data encryption is realized.

[0051] In addition, the DNA coding and decoding process is simple and efficient, suitable for parallel computing, especially suitable for encryption requirements in large-capacity high-speed communication. Therefore, as an intermediate layer of constellation data encryption, DNA coding not only improves the complexity and dynamics of the system, but also shows significant advantages in security, anti-analysis and real-time performance. The existing encryption method generally uses a sequential encoding method, which is limited by the computing power of existing devices and cannot meet the encryption requirements of large-capacity high-speed low-latency communication systems.

[0052] Preferably, the present application proposes a multi-level DNA disturbance structure on the basis of the traditional DNA coding encryption mechanism, further deepening the disturbance path of the constellation data at the base level, and improving the threshold of its reverse cracking. The specific steps are as follows: first, the quantized I / Q data in the constellation is DNA coded to generate an initial base sequence; second, based on the first group of pseudo-random control sequences, the first stage of DNA operation (such as DNA XOR or addition) is performed; then, the second group of independent pseudo-random DNA sequences is introduced to perform high-level disturbance operations such as DNA bit replacement, base rearrangement or complementary mapping, forming a nested disturbance process; finally, DNA decoding is performed under the control of new rules to generate the final encrypted constellation numerical data. The multi-level DNA encryption path breaks the traditional single mapping mode, introduces multiple independent disturbance stages at the rule layer, operation layer and disturbance path layer, effectively prevents the pattern exposure caused by fixed DNA rules, improves the complexity and irreversibility of the encryption link, and enhances the overall anti-attack ability and security robustness of the system.

[0053] Embodiment 2 On the basis of embodiment 1, the encryption method based on dynamic coupling mapping grid of the application is mainly implemented on the FPGA platform, and is mainly applied to constellation scrambling encryption in the OFDM modulation system. The FPGA encryption system comprises a key sequence processing module, a one-dimensional TENT chaotic pseudo-random sequence generation module, a two-dimensional HENON chaotic-coupling mapping grid fusion module and a DNA parallel encryption module. The key sequence processing module is used for executing step S21 in embodiment 1, the one-dimensional TENT chaotic pseudo-random sequence generation module is used for executing step S22 in embodiment 1, the two-dimensional HENON chaotic-coupling mapping grid fusion module is used for executing step S23 in embodiment 1, and the DNA parallel encryption module is used for executing step S24 in embodiment 1.

[0054] Preferably, the constellation data in the application is further subjected to structured scrambling processing, the I component and the Q component in the constellation are extracted and independently taken as encryption objects, and different chaotic scrambling paths are introduced for encryption. Specifically, the I component is driven by a first chaotic path generated by TENT mapping for DNA coding and scrambling, and the Q component is controlled by a second chaotic path generated by the HENON mapping and coupling mapping grid fusion model. The two components independently evolve in terms of scrambling rules, operation operations and disturbance intensity, thereby forming heterogeneous encryption paths. Finally, the scrambled I / Q components are recombined according to the original symbol structure, and the final encrypted constellation data is output. This structure realizes the separation scrambling of the constellation at the data channel level, constructs the data dimension interleaving encryption mechanism, significantly enhances the protection capability against dimension analysis attack, I / Q reconstruction attack and constellation clustering recognition attack, and further improves the security of physical layer encryption.

[0055] This invention fuses a one-dimensional coupled mapping lattice model with a two-dimensional HENON chaotic mapping model and a one-dimensional TENT chaotic mapping model. Combined with the excellent data obfuscation and diffusion effects of DNA encoding, it possesses strong resistance to statistical analysis attacks, high complexity, and security, while effectively increasing the parameter space and key space of the pseudo-random sequence generator. In particular, it addresses the phenomenon where, after a finite number of iterations, the floating-point numbers in the computation exceed the operational precision or storage limit of the hardware and software platform, causing the iterative sequence to converge to a fixed point or enter a periodic loop, resulting in chaotic dynamics degradation. It exhibits stronger chaotic characteristics. The introduction of a spatiotemporal chaotic system effectively improves the complexity, pseudo-randomness, and disorder of low-dimensional chaotic systems. It fully utilizes the advantage of low-dimensional chaotic systems, which do not require complex calculations, and simultaneously optimizes the coupled mapping lattice and DNA encoding algorithms in parallel. This solves the problems of long execution time, slow speed, and low efficiency associated with sequential key generation or encryption algorithms, greatly improving key generation and encryption efficiency and meeting the encryption requirements of high-capacity, high-speed, and low-latency communication systems.

[0056] Example 3: Based on Example 1, when using this method, step S3 is further included after step S2. Step S3 is as follows: S3 performs dynamic optimization of signal energy. In OFDM digital communication modulation systems, a constellation diagram is a graphical tool used to represent the distribution of modulated signals in the complex plane. The distance between a point on the constellation diagram and the origin represents the energy of the signal represented by that point. By optimizing signal energy, the power consumption of power amplifier devices can be reduced, the efficiency of power amplifiers can be increased, transmission power can be reduced, signal distortion or nonlinear distortion can be avoided, and the bit error rate can be reduced. The mathematical expression is as follows: in It's on the constellation chart. Energy at coordinate points These are the constellation coordinates of the I component. These are the constellation coordinates of the Q component.

[0057] This invention performs m time-dimensional iterations on a coupled one-dimensional coupled mapping lattice, encrypts constellation diagram IQ data packets using m sets of generated one-dimensional pseudo-random sequences, generates m sets of ciphertext constellation diagram IQ data packets, calculates the total energy value of each of the m sets of constellation diagram IQ data packets, and then transmits the ciphertext constellation diagram IQ data packet with the lowest total energy value. The formula for calculating the total energy value P of the ciphertext constellation diagram IQ data is as follows: (j) in, is the length of each encrypted data packet, j (j = 1, 2, 3, …, N) is the index sequence of each data value of the data packet, is the energy value of the jth data. Correspondingly, the increasing signal energy dynamic optimization module realizes the above process.

[0058] The above only is the preferred embodiment of the present application, and does not limit the present application, for those skilled in the art, the present application can have various changes and variations. Any modification, equivalent replacement, improvement, etc. within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A dynamic coupling image grid-based encryption method, the method comprising the following steps: S1, obtaining constellation data to be encrypted, taking the constellation data as plaintext data; S2, DNA encoding the plaintext data, then performing an operation, and then DNA decoding, completing data scrambling encryption to obtain ciphertext data of the constellation data; the rules of the DNA encoding, the operation, and the DNA decoding are determined by a preset method; characterized in that The preset method is as follows: S21, obtaining a key sequence and dividing the key sequence to obtain an encryption parameter; S22, generating a first intermediate one-dimensional pseudo-random sequence by using a first chaotic mapping model; the initial value and the chaotic control parameter of the first chaotic mapping model are determined by the encryption parameter; S23, dynamically iterating the first intermediate one-dimensional pseudo-random sequence by using a second chaotic mapping model fusion one-dimensional coupling image grid model to obtain a second intermediate one-dimensional pseudo-random sequence; The initial value and the chaotic control parameter of the second chaotic mapping model, the time iteration parameter and the coupling coefficient parameter of the one-dimensional coupling image grid model are determined by the encryption parameter; S24, determining the rules of the DNA encoding, the operation, and the DNA decoding by the second intermediate one-dimensional pseudo-random sequence.

2. The encryption method based on dynamic coupling mapping grid according to claim 1, characterized in that, In the S23, the first intermediate one-dimensional pseudo-random sequence is input into the one-dimensional coupling image grid model, and the one-dimensional coupling image grid model outputs the second intermediate one-dimensional pseudo-random sequence.

3. The encryption method based on dynamic coupling mapping grid according to claim 2, characterized in that, The coupling mapping function in the one-dimensional coupling image grid model is a first mapping function in the second chaotic mapping model.

4. The encryption method based on dynamic coupling mapping grid according to claim 3, characterized in that, The coupling strength factor in the one-dimensional coupling image grid model is a second mapping function in the second chaotic mapping model.

5. The encryption method based on dynamic coupling mapping grid according to claim 4, characterized in that, The second chaotic mapping model is a two-dimensional HENON chaotic mapping model, and the expression is as follows: wherein n is a sequence dimension value, , is a current state value, is a chaotic control parameter of the first mapping function, is a chaotic control parameter of the second mapping function, , is a result of the first mapping function, the second mapping function.

6. The encryption method based on dynamic coupling mapping grid according to claim 5, characterized in that, The expression of the one-dimensional coupling image grid model is as follows: wherein is a coupling strength factor, i.e. the second mapping function, , , are the coupling mapping functions, i.e. the first mapping functions, for sequence dimension values n-1, n-2, n, respectively.

7. The encryption method based on dynamic coupling mapping grid according to claim 6, characterized in that, The period boundary constraint condition of the one-dimensional coupling image grid model is as follows: wherein, is the sequence dimension value, L is the total length of the index, i.e. the total number of lattices.

8. The encryption method based on dynamic coupling mapping grid according to claim 7, characterized in that, The first chaotic mapping model is a one-dimensional TENT chaotic mapping model, and the expression is as follows: wherein, is a sequence index value, is a current state value, is a chaos control parameter of the first chaotic mapping model.

9. The encryption method based on dynamic coupling mapping grid according to claim 8, characterized in that, In the S23, a plurality of one-dimensional coupling image grid models are used for parallel processing.

10. The encryption method based on dynamic coupling mapping grid according to claim 9, characterized in that, The plaintext data is constellation data output by an OFDM modulation system.

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