A signal transmission method, a signal reception method, a channel sending end and a channel receiving end

Abstract

The application discloses a signal transmission method, a signal receiving method, a channel sending end and a channel receiving end, and belongs to the technical field of communication. The signal transmission method comprises the following steps: acquiring original data to be sent and generating a bit encryption factor, a constellation encryption factor, a bit disturbance factor and a constellation disturbance factor; dividing the original data to be sent into an even number of data blocks according to a preset rule to construct a complete binary tree, and performing first traversal encryption and primary disturbance on the data blocks by using the bit encryption factor; converting the data blocks after the primary disturbance into parallel bit streams through serial-parallel conversion, performing QAM mapping on the parallel bit streams, and performing second traversal encryption and secondary disturbance on the parallel bit streams according to the constellation disturbance factor; converting the parallel bit streams after the secondary disturbance into serial signals through a discrete Fresnel inverse transformation matrix and parallel-serial conversion; and performing up-conversion processing on the serial signals and transmitting the serial signals to a transmission channel. The application solves the problem of insufficient security protection in the actual application of the prior art.

Description

TECHNICAL FIELD

[0001] The present application relates to a signal transmission method, a signal receiving method, a channel sending end and a channel receiving end, and belongs to the technical field of communication. BACKGROUND

[0002] With the continuous development of emerging technologies such as big data, Internet of Things and cloud computing, the demand for information transmission is growing explosively, and the optical interconnection network is facing the pressure of capacity expansion. At the same time, the security risks of communication data in the switching process are increasingly prominent. The orthogonal chirp division multiplexing (OCDM, Orthogonal Chirp Division Multiplexing) technology gradually attracts attention due to its high anti-interference ability, high spectral efficiency and high compatibility with OFDM (Orthogonal Frequency Division Multiplexing) system. The chirp waveform of OCDM has strong pulse compression and spread spectrum ability, and can effectively utilize the multipath diversity characteristics, and is superior to OFDM in performance. To cope with security challenges, in the prior art, the security strategy based on digital domain chaos encryption provides complexity and unpredictability support for communication encryption due to the extreme sensitivity, dynamic nonlinear behavior and high entropy characteristics of the chaos system. The chaos sequence shows excellent security in data scrambling, key generation and mapping control, and has little effect on system throughput. In addition, the binary tree structure as a classic data structure provides flexible path control ability for hierarchical encryption mechanism through various traversal methods such as pre-order traversal, in-order traversal, post-order traversal and level-order traversal, which can enhance the randomness and complexity of the encryption algorithm.

[0003] Although the OCDM technology has advantages, its widespread deployment in high-throughput scenarios also brings complex security challenges: the risk of malicious eavesdropping and information tampering increases significantly, and the system protection ability needs to be enhanced. At the same time, the point-to-multipoint downlink broadcast transmission mechanism in the passive optical network system makes it possible for any user to receive the downlink signals of other users, further threatening data security. The prior art still has the problem of insufficient security protection in practical application, and developing an efficient physical layer security mechanism to build a solid information protection barrier is an important direction for the evolution of optical communication systems. SUMMARY

[0004] The purpose of the present application is to provide a signal transmission method, a signal receiving method, a channel sending end and a channel receiving end, which solves the problem of insufficient security protection in practical application of the prior art by completely binary tree hierarchical joint encryption of bit information and constellation mapping.

[0005] To solve the above technical problems, the present application is realized by the following technical scheme.

[0006] In a first aspect, the present invention provides a signal transmission method, executed by a channel transmitter, comprising:

[0007] Obtain the raw data to be sent and the initial key value;

[0008] Four sets of chaotic sequences are synchronously generated using a hyperchaotic system based on the initial key value;

[0009] Two sets of chaotic sequences are used to generate bit encryption factors and constellation encryption factors;

[0010] The bit perturbation factor and constellation perturbation factor are generated using two other sets of chaotic sequences;

[0011] The raw data to be sent is divided into an even number of data blocks according to a preset rule to construct a complete binary tree, where leaf nodes store data blocks and non-leaf nodes store hierarchically encoded routing information.

[0012] Based on bit encryption factor and bit perturbation factor, the data block is first traversed and encrypted and then perturbed using bit encryption factor.

[0013] The data blocks after the initial perturbation are converted into a parallel bit stream through serial-to-parallel conversion;

[0014] Based on the constellation encryption factor and constellation perturbation factor, QAM mapping is performed on the parallel bit stream, and a second traversal encryption and a second perturbation are performed according to the constellation perturbation factor.

[0015] The parallel bit stream after the second perturbation is converted into a serial signal through the discrete Fresnel inverse transform matrix and parallel-to-serial conversion;

[0016] The serial signal is up-converted and then transmitted to the transmission channel.

[0017] Furthermore, the hyperchaotic system includes a Zhan-4D hyperchaotic system, which is represented as follows:

[0018] ;

[0019] In the formula, State variables representing the horizontal axis of the Zhan-4D hyperchaotic system The first derivative, State variables representing the vertical axis of the Zhan-4D hyperchaotic system The first derivative, State variables representing the vertical axes of the Zhan-4D hyperchaotic system The first derivative, This represents the state feedback control parameters of the Zhan-4D hyperchaotic system. The first derivative, a first system parameter representing a Zhan-4D hyperchaotic model, a second system parameter representing a Zhan-4D hyperchaotic model, a third system parameter representing a Zhan-4D hyperchaotic model, a fourth system parameter representing a Zhan-4D hyperchaotic model, a fifth system parameter representing a Zhan-4D hyperchaotic model, a sixth system parameter representing a Zhan-4D hyperchaotic model, a seventh system parameter representing a Zhan-4D hyperchaotic model, an eighth system parameter representing a Zhan-4D hyperchaotic model, wherein, 、 、 、 、 、 、 and co-control the chaotic behavior of the Zhan-4D hyperchaotic system.

[0020] Further, the bit encryption factor, the bit perturbation factor, the constellation encryption factor and the constellation perturbation factor are respectively represented as:

[0021] ;

[0022] In the formula, bit encryption factor, bit perturbation factor, constellation encryption factor, constellation perturbation factor, remainder operation, rounding function to negative infinity, first chaotic sequence in the four groups of chaotic sequences, second chaotic sequence in the four groups of chaotic sequences, third chaotic sequence in the four groups of chaotic sequences, fourth chaotic sequence in the four groups of chaotic sequences.

[0023] Further, it further comprises:

[0024] The following recursive operation is performed on the data block stored in each leaf node of the complete binary tree:

[0025] The current data block is evenly divided into an even number of sub-data blocks according to the same preset rule;

[0026] A corresponding complete binary tree is constructed for each sub-data block as a sub-complete binary tree;

[0027] The recursion stops until the data block reaches a minimum granularity, wherein the minimum granularity is a bit data stream.

[0028] Further, the primary perturbation or the secondary perturbation comprises:

[0029] At each recursive level of the complete binary tree, a preset perturbation algorithm is performed on the current sub-complete binary tree to independently perform perturbation processing.

[0030] Further, the method for traversing the data block comprises: pre-order traversal, in-order traversal, post-order traversal, and level-order traversal.

[0031] In a second aspect, the present application provides a signal receiving method, executed by a channel receiving end, comprising:

[0032] Receiving the up-converted serial signal in the transmission channel and generating four groups of chaotic sequences identical to those of the channel transmitting end by using the hyper-chaotic system synchronization based on the same key initial value as the channel transmitting end;

[0033] Generating a bit encryption factor and a constellation encryption factor by using two groups of chaotic sequences;

[0034] Generating a bit perturbation factor and a constellation perturbation factor by using the other two groups of chaotic sequences;

[0035] Down-converting the up-converted serial signal to recover the serial signal;

[0036] Recovering the parallel bit stream after the secondary perturbation by serial-parallel conversion and discrete Fresnel transform matrix from the serial signal;

[0037] Based on the constellation encryption factor and the constellation perturbation factor, performing QAM inverse mapping on the parallel bit stream and performing second traversal decryption and secondary perturbation according to the constellation perturbation factor;

[0038] Recovering the data block after the primary perturbation by parallel-serial conversion from the parallel bit stream;

[0039] Based on the bit encryption factor and the bit perturbation factor, removing the primary perturbation and performing traversal decryption to recover the data block stored in the leaf node from the data block after the primary perturbation according to the bit encryption factor;

[0040] According to the complete binary tree block structure, based on the hierarchical encoding routing information stored in the non-leaf node, the data block stored in the leaf node is combined and recovered into the original data according to the same preset rule as the channel transmitting end.

[0041] Further, the discrete Fresnel transform matrix is represented as:

[0042] ;

[0043] wherein, denotes a Fresnel transform the modulation signal of the item in the row and the column of the matrix, denotes the number of chirp subcarriers, denotes a vector, denotes a remainder operation.

[0044] In a third aspect, the present application provides a channel sending end, comprising the following modules:

[0045] a data acquisition module, configured to acquire original data to be sent and a key initial value;

[0046] a factor generation module, configured to generate four groups of chaotic sequences by using hyperchaotic system synchronization based on the key initial value; generate a bit encryption factor and a constellation encryption factor by using two groups of chaotic sequences, and generate a bit disturbance factor and a constellation disturbance factor by using the other two groups of chaotic sequences;

[0047] a data construction module, configured to divide the original data to be sent into an even number of data blocks according to a preset rule to construct a complete binary tree, wherein leaf nodes store data blocks, and non-leaf nodes store hierarchical encoding routing information;

[0048] a primary encryption module, configured to perform first traversal encryption and primary disturbance on the data blocks by using the bit encryption factor based on the bit encryption factor and the bit disturbance factor;

[0049] a time-frequency conversion module, configured to convert the data blocks after the primary disturbance into parallel bit streams through serial-parallel conversion;

[0050] a secondary encryption module, configured to perform QAM mapping on the parallel bit streams based on the constellation encryption factor and the constellation disturbance factor, and perform second traversal encryption and secondary disturbance according to the constellation disturbance factor;

[0051] a signal conversion module, configured to convert the parallel bit streams after the secondary disturbance into a serial signal through a discrete inverse Fresnel transform matrix and parallel-serial conversion;

[0052] a frequency conversion processing module, configured to perform up-conversion processing on the serial signal and transmit the serial signal to a transmission channel.

[0053] In a fourth aspect, the present application provides a channel receiving end, comprising the following modules:

[0054] a data acquisition module, configured to receive the serial signal after the up-conversion processing in the transmission channel and generate four groups of chaotic sequences identical to those of the channel sending end by using hyperchaotic system synchronization based on the same key initial value as that of the channel sending end;

[0055] A factor generation module is configured to generate a bit encryption factor and a constellation encryption factor by using two groups of chaotic sequences, and generate a bit disturbance factor and a constellation disturbance factor by using another two groups of chaotic sequences;

[0056] A frequency conversion inverse processing module is configured to perform frequency down-conversion processing on the up-converted serial signal to restore the serial signal.

[0057] A signal inverse conversion module is configured to restore the parallel bit stream after the secondary disturbance by serial-parallel conversion and a discrete Fresnel transform matrix.

[0058] A secondary decryption module is configured to remove the primary disturbance from the data block after the primary disturbance and perform traversal decryption to restore the data block stored in the leaf node based on the bit encryption factor and the bit disturbance factor.

[0059] A time-frequency inverse conversion module is configured to restore the data block after the primary disturbance by parallel-serial conversion.

[0060] A primary decryption module is configured to remove the primary disturbance from the data block after the primary disturbance and perform traversal decryption to restore the data block stored in the leaf node based on the bit encryption factor and the bit disturbance factor.

[0061] A data reconstruction module is configured to combine and restore the data block stored in the leaf node into the original data according to the same preset rule as the channel sending end based on the hierarchical encoding routing information stored in the non-leaf node according to the complete binary tree block structure.

[0062] The up-converted serial signal is obtained by the signal transmission method of the first aspect.

[0063] Compared with the prior art, the present application has the following advantages:

[0064] 1. The present application effectively reduces the path complexity of data block traversal encryption by storing the hierarchical encoding routing information of the non-leaf node based on the hierarchical architecture of the complete binary tree in the channel sending end, and generates the bit encryption factor, the bit disturbance factor, the constellation encryption factor and the constellation disturbance factor by using hyper-chaotic sequences, which significantly improves the ability to resist malicious eavesdropping and information tampering by using two independent traversal encryptions. At the same time, the introduction of the discrete Fresnel inverse transform matrix further optimizes the signal spectrum characteristics, while maintaining high anti-interference performance, improves the security level of the system, and is suitable for high security requirements in broadcast transmission scenarios such as passive optical networks, solving the problem of insufficient security protection in practical application of the prior art.

[0065] 2、The application stores the hierarchical coding routing information of the non-leaf node based on the hierarchical structure of the complete binary tree at the channel receiving end, ensures that the leaf node data block is accurately combined at the channel receiving end according to the preset rule consistent with the channel sending end, reduces the complexity and error rate of data recombination, generates a bit encryption factor and a constellation disturbance factor through a hyper-chaotic sequence, uses two independent traversal decryption, and is completely reversed and aligned with the encryption process of the channel sending end, thereby significantly improving the robustness against noise interference and malicious attacks. Meanwhile, the discrete Fresnel transform matrix is introduced to further optimize the signal spectrum recovery accuracy through strict correspondence with the inverse transform, reduce the system security synchronization error rate while maintaining high demodulation efficiency, and is suitable for high-reliability receiving requirements in broadcast transmission scenarios such as passive optical networks. BRIEF DESCRIPTION OF DRAWINGS

[0066] Figure 1 is a whole schematic diagram of a signal transmission method and a signal receiving method provided by an embodiment of the application;

[0067] Figure 2 is a principle schematic diagram of OCDM modulation and demodulation provided by an embodiment of the application;

[0068] Figure 3 is a structure schematic diagram of a complete binary tree provided by an embodiment of the application;

[0069] Figure 4 is a data block schematic diagram under different traversal modes provided by an embodiment of the application;

[0070] Figure 5 is a flowchart schematic diagram of constructing a complete binary tree provided by an embodiment of the application;

[0071] Figure 6 is a secondary disturbance schematic diagram provided by an embodiment of the application;

[0072] Figure 7 is an attractor phase diagram schematic diagram of a Zhan-4D hyper-chaotic system provided by an embodiment of the application;

[0073] Figure 8 is a key sensitivity schematic diagram of a Zhan-4D hyper-chaotic model provided by an embodiment of the application. DETAILED DESCRIPTION

[0074] The technical scheme of the application will be described in detail below with reference to the drawings and specific embodiments. It should be understood that the specific features in the embodiments and the specific features in the embodiments are detailed descriptions of the technical scheme of the application, and are not limitations of the technical scheme of the application. In the case of no conflict, the technical features in the embodiments and the embodiments can be combined with each other.

[0075] The term "and / or", only describes the association relation of the associated objects, indicates that there can be three relations, for example, A and / or B, which can represent the three cases of A alone, A and B together, and B alone. In addition, the character " / " generally represents that the associated objects before and after are in an "or" relationship.

[0076] Embodiment 1

[0077] This embodiment introduces a signal transmission method, which is executed by a channel sending end, comprising:

[0078] Step one: obtaining the original data to be sent and the key initial value;

[0079] This embodiment obtains the original data to be sent and the key initial value, uses the extreme sensitivity of the initial condition and the control parameter, and the high entropy characteristics to provide a high complexity and unpredictable random sequence source for the subsequent encryption and disturbance process. Compared with the traditional pseudo-random sequence, the dynamic nonlinear behavior of the hyperchaotic sequence significantly enhances the anti-cracking ability of the key space, and builds a reliable randomness foundation for the physical layer security mechanism.

[0080] Step two: generating four groups of chaotic sequences based on the key initial value using the hyperchaotic system synchronization, generating bit encryption factors and constellation encryption factors using two groups of chaotic sequences, and generating bit disturbance factors and constellation disturbance factors using the other two groups of chaotic sequences.

[0081] This embodiment independently generates bit encryption factors and constellation encryption factors, as well as bit disturbance factors and constellation disturbance factors by grouping, realizing the decoupling control of the encryption and disturbance process. Bit encryption factors and bit disturbance factors focus on the basic security protection at the data block level, and constellation encryption factors and constellation disturbance factors interfere deeply at the modulation symbol layer. The dual-factor cooperative action can effectively resist chosen-plaintext attacks and statistical analysis attacks, and improves the system anti-eavesdropping ability compared with the traditional single-factor encryption scheme.

[0082] Step three: dividing the original data to be sent into an even number of data blocks according to a preset rule to construct a complete binary tree, wherein the leaf nodes store data blocks, and the non-leaf nodes store hierarchical encoding routing information.

[0083] This embodiment realizes the explicit control of the data block processing path by storing hierarchical encoding routing information in non-leaf nodes based on the hierarchical architecture of the complete binary tree. Compared with the linear structure, the binary tree structure reduces the traversal complexity of the data block, and the hierarchical storage of the routing information provides accurate path guidance for the data reorganization of the subsequent decryption end, significantly reducing the error rate of the channel receiving end.

[0084] Step four: based on the bit encryption factor and the bit disturbance factor, using the bit encryption factor to perform the first traversal encryption and primary disturbance on the data block.

[0085] The first traversal encryption is performed on the data block by a bit encryption factor, and a primary disturbance mechanism is combined to establish a basic security barrier at the data block level. The traversal encryption ensures that each data bit is independently encrypted, and the primary disturbance destroys the statistical characteristics of the data by bit flipping or permutation driven by a chaotic sequence, thereby improving the threshold for malicious eavesdroppers to obtain effective information.

[0086] Step five: The data block after the primary disturbance is converted into a parallel bit stream through serial-parallel conversion.

[0087] The serial data stream is reconstructed into a parallel bit stream through serial-parallel conversion, which provides parallel processing capability for QAM mapping and secondary disturbance. Compared with serial processing, the parallel architecture improves the system throughput, and the independent channel characteristics of the parallel bit stream provide physical layer support for the implementation of the layered encryption mechanism.

[0088] Step six: Based on the constellation encryption factor and the constellation disturbance factor, the parallel bit stream is QAM mapped, and the second traversal encryption and secondary disturbance are performed according to the constellation disturbance factor.

[0089] The parallel bit stream is converted into modulation symbols through QAM mapping, and the second traversal encryption and secondary disturbance are performed in combination with the constellation disturbance factor to establish a deep security protection at the symbol level. The secondary disturbance destroys the correlation between symbols through constellation point offset or phase rotation driven by a chaotic sequence, thereby improving the noise immunity of traditional QAM mapping.

[0090] Step seven: The parallel bit stream after secondary disturbance is converted into a serial signal through a discrete Fresnel inverse transform matrix and serial-parallel conversion.

[0091] The signal spectrum characteristics are optimized through frequency-time domain conversion by the discrete Fresnel inverse transform matrix, which reduces the peak-to-average power ratio and effectively suppresses nonlinear distortion. In addition, the serial signal is reconstructed through serial-parallel conversion, which maintains high anti-interference performance while improving system spectral efficiency.

[0092] Step eight: The serial signal is up-converted and transmitted to the transmission channel.

[0093] The baseband signal is shifted to a high frequency band through up-conversion, which expands the spectral coverage of signal transmission and adapts to the characteristics of multipath fading channels. Compared with direct transmission, the up-conversion mechanism reduces signal penetration loss, and high-frequency deployment effectively avoids low-frequency congestion, thereby improving the capacity expansion capability of optical interconnection networks in high-concurrency scenarios.

[0094] Embodiment 2

[0095] Based on the same inventive concept as example 1, this embodiment introduces a signal receiving method, executed by a channel receiving end, comprising:

[0096] Step one: receive the up-converted serial signal in the transmission channel and generate four groups of chaotic sequences identical to the channel sending end based on the same key initial value and the super chaotic system synchronization.

[0097] This embodiment uses the channel receiving end to generate four groups of chaotic sequences identical to the channel sending end through super chaotic system synchronization, and uses the initial condition sensitivity and dynamic evolution consistency of the super chaotic system to ensure the high matching of the key space of the encryption and decryption ends. Compared with the non-synchronous chaotic system, the key mismatch rate is reduced, and a reliable randomness basis is provided, which fundamentally guarantees the reversibility of the physical layer security mechanism.

[0098] Step two: generate bit encryption factors and constellation encryption factors using two groups of chaotic sequences, and generate bit disturbance factors and constellation disturbance factors using the other two groups of chaotic sequences.

[0099] This embodiment independently generates bit encryption factors and constellation disturbance factors by grouping, realizing decoupling control of the decryption process of the channel receiving end. The bit encryption factor focuses on basic security removal at the data block level, and the constellation disturbance factor performs deep descrambling at the modulation symbol layer, and the two work together to effectively resist chosen ciphertext attacks and differential attacks, improving the system cracking resistance.

[0100] Step three: down-convert the up-converted serial signal to restore it to a serial signal.

[0101] This embodiment migrates the high-frequency serial signal to the baseband frequency band through down-conversion, significantly reducing signal penetration loss and multipath fading effects. Compared with directly processing high-frequency signals, the down-conversion mechanism improves the receiving sensitivity, and the low-frequency characteristics of the baseband signal provide more stable physical layer support for subsequent serial-parallel conversion and digital signal processing.

[0102] Step four: restore the serial signal to a parallel bit stream after secondary disturbance through serial-parallel conversion and discrete Fresnel transform matrix.

[0103] This embodiment reconstructs the serial signal into a parallel bit stream through serial-parallel conversion, and recovers the frequency spectrum characteristics of the inverse discrete Fresnel transform of the channel sending end by combining the frequency domain and time domain conversion characteristics of the discrete Fresnel transform matrix. Compared with traditional FFT transform, the DFrT matrix reduces the signal spectrum distortion rate, providing a high-fidelity parallel data source for subsequent constellation descrambling and QAM demapping.

[0104] Step five: QAM inverse mapping is performed on the parallel bit stream based on the constellation encryption factor and the constellation perturbation factor, and second traversal decryption and secondary perturbation are performed according to the constellation perturbation factor.

[0105] The embodiment implements secondary perturbation removal and traversal decryption through the constellation perturbation factor, combines QAM demapping, and establishes a deep security demodulation mechanism at the symbol level. The secondary perturbation removal is implemented through the reverse offset or phase rotation of the constellation point driven by the chaotic sequence, accurately restores the constellation perturbation effect of the channel sending end, reduces the demodulation symbol error rate of the traditional QAM system, and the traversal decryption ensures that each symbol is independently verified, thereby significantly improving the anti-noise interference capability.

[0106] Step six: The parallel bit stream is converted into a data block after the first perturbation through parallel-serial conversion.

[0107] The embodiment reconstructs the parallel bit stream into a serial data block through parallel-serial conversion, and provides an efficient processing architecture for the first perturbation removal at the data block level. Compared with parallel processing, the serial architecture reduces the processing delay of the channel receiving end, and the continuity of the serial data block provides an accurate timing alignment basis for the data reorganization of the complete binary tree structure.

[0108] Step seven: Based on the bit encryption factor and the bit perturbation factor, the first perturbation is removed from the data block after the first perturbation and traversal decryption is performed according to the bit encryption factor to restore the data block stored in the leaf node.

[0109] The embodiment implements first perturbation removal and traversal decryption through the bit encryption factor, establishes a reverse mechanism of basic security protection at the data block level, and the traversal decryption ensures that each data bit is independently verified. Combined with the bit flip or permutation restoration driven by the chaotic sequence, the detection rate of malicious tampered data is improved, and the routing information stored in the non-leaf node is cooperated to provide a path basis for accurate positioning of the data block.

[0110] Step eight: According to the complete binary tree block structure, based on the hierarchical encoding routing information stored in the non-leaf node, the data block stored in the leaf node is combined and restored into the original data according to the same preset rule as the channel sending end.

[0111] The embodiment realizes explicit reverse tracking of the data block processing path based on the hierarchical architecture of the complete binary tree through the hierarchical encoding routing information stored in the non-leaf node. Compared with the linear structure, the binary tree structure reduces the data block reorganization complexity, and the hierarchical storage of the routing information ensures that the leaf node data block is accurately combined according to the preset rule of the channel sending end, thereby reducing the error rate of the channel receiving end.

[0112] Embodiment 3

[0113] As Figure 1As shown, based on the same inventive concept as other embodiments, this embodiment introduces the implementation steps of a signal transmission method and a corresponding signal reception method. This embodiment first uses the Zhan-4D hyperchaotic system to generate four sets of chaotic sequences. Then, it uses two sets of chaotic sequences to determine the traversal methods of data bits and constellation mapping rules, respectively. Finally, it uses the other two sets of chaotic sequences to define the traversal rules of a complete binary tree to achieve layered binary tree encryption. This reduces algorithm complexity while achieving high-security transmission of large amounts of data. By integrating chaotic dynamics with the complexity of tree structures, this embodiment enhances the randomness and unpredictability of the encryption system, ensuring the security of information transmission. The scheme provided in this embodiment has a key space of up to 10191, significantly improving the encryption system's resistance to attacks and making it suitable for building future-oriented high-security optical communication network architectures.

[0114] Perform the following steps at the channel transmitting end:

[0115] Step 1: Obtain the raw data to be sent and the initial key value.

[0116] Step 2: Based on the initial key value, use the hyperchaotic system to synchronously generate four sets of chaotic sequences. Use two sets of chaotic sequences to generate bit encryption factors and constellation encryption factors, and use the other two sets of chaotic sequences to generate bit perturbation factors and constellation perturbation factors.

[0117] In this embodiment, the hyperchaotic system includes a Zhan-4D hyperchaotic system, which is represented as follows:

[0118] ;

[0119] In the formula, State variables representing the horizontal axis of the Zhan-4D hyperchaotic system The first derivative, State variables representing the vertical axis of the Zhan-4D hyperchaotic system The first derivative, State variables representing the vertical axes of the Zhan-4D hyperchaotic system The first derivative, This represents the state feedback control parameters of the Zhan-4D hyperchaotic system. The first derivative, This represents the first system parameter of the Zhan-4D hyperchaotic model. This represents the second system parameter of the Zhan-4D hyperchaotic model. This represents the third system parameter of the Zhan-4D hyperchaotic model. This represents the fourth system parameter of the Zhan-4D hyperchaotic model. a fifth system parameter of a Zhan-4D hyperchaotic model, a sixth system parameter of the Zhan-4D hyperchaotic model, a seventh system parameter of the Zhan-4D hyperchaotic model, an eighth system parameter of the Zhan-4D hyperchaotic model, , , , , , , and jointly control the chaotic behavior of the Zhan-4D hyperchaotic system.

[0120] When = 8, =-1, =-40, =1, =2, =-14, =1, =-2, the Zhan-4D hyperchaotic system is in a hyperchaotic state and has a four-wing property. The dynamic behavior of the four-wing hyperchaotic system is more complex and is suitable for data encryption processing. Figure 7 is a schematic diagram of an attractor phase portrait of a Zhan-4D hyperchaotic system provided by an embodiment of the present application, wherein Figure 7 (a) in (a) represents a projection of the attractor phase portrait in x-y-z, Figure 7 (b) in (b) represents a projection of the attractor phase portrait in x-y, Figure 7 (c) in (c) represents a projection of the attractor phase portrait in x-z, Figure 7 (d) in (d) represents a projection of the attractor phase portrait in y-z; in Figure 7 , the initial condition ( , , , )=(0.1, 0.1, 0.1, 0.1), it can be seen that the phase portrait of the Zhan-4D hyperchaotic model shows complex chaotic trajectories and bifurcation dynamics. Due to the sensitivity of the hyperchaotic model to initial values, when the chaotic initial value changes slightly, almost completely different complex chaotic trajectories are generated.

[0121] When , , , After the chaotic sequence, the bit stream and 16QAM constellation cannot be directly encrypted, and the data preprocessing of the chaotic sequence is needed to match the signal format. In the embodiment, the bit encryption factor, the bit disturbance factor, the constellation encryption factor and the constellation disturbance factor are respectively represented as:

[0122]

[0123] In the formula, bit encryption factor is represented as, bit disturbance factor is represented as, constellation encryption factor is represented as, constellation disturbance factor is represented as, remainder operation is represented as, rounding function to negative infinity is represented as, the first chaotic sequence in the four groups of chaotic sequences is represented as, the second chaotic sequence in the four groups of chaotic sequences is represented as, the third chaotic sequence in the four groups of chaotic sequences is represented as, the fourth chaotic sequence in the four groups of chaotic sequences is represented as.

[0124] Step 3: The original data to be sent is divided into an even number of data blocks according to a predetermined rule to construct a complete binary tree.

[0125] The complete binary tree is a typical tree data structure, in which each node has at most two child nodes, called left child node and right child node, as shown in Figure 3 The complete binary tree structure has good hierarchical organization and controllable traversal in computer algorithms. Commonly used traversal methods include pre-order traversal, in-order traversal, post-order traversal and level-order traversal. Due to the fundamental difference in the order of node access, the same complete binary tree can generate completely different node sequences under different traversal methods, providing a natural disturbance space for data encryption.

[0126] In the embodiment, a group of encrypted bit streams with a specific arrangement order can be obtained by selecting a specific traversal method for node access of the complete binary tree. As shown in Figure 4 the bit sequence [101110011011101] will produce completely different encoding results under different traversal methods. Due to the significant difference in the order of node access corresponding to various traversal methods, without effective information of the traversal method and tree construction rule, external attackers will have difficulty in restoring the original data. The diversity of the traversal method significantly improves the security of the system, and also lays a structural foundation for deep encryption operations based on hierarchical structure. The channel receiving end only needs to synchronize the relevant traversal information to reversely restore the original bit stream according to the rule, and realize the reversible encryption process based on key control. ​

[0127] However, in the actual data transmission process, the bit stream is relatively long, in order to deal with the calculation overhead brought by large-scale data stream, the embodiment stipulates the traversal rule of the complete binary tree, as shown in Figure 5 , including:

[0128] The following recursive operation is performed on the data block stored in each leaf node of the complete binary tree:

[0129] The current data block is evenly divided into an even number of sub-data blocks according to the same preset rule;

[0130] A corresponding complete binary tree is constructed for each sub-data block as a sub-complete binary tree;

[0131] The recursion stops until the data block reaches the minimum granularity, wherein the minimum granularity is a bit data stream.

[0132] In the embodiment, the traversal rule of the complete binary tree significantly reduces the size of the traversed tree, thereby effectively controlling the time complexity and resource consumption of the encryption algorithm.

[0133] Step 4: Based on the bit encryption factor and the bit perturbation factor, the bit encryption factor is used to perform first traversal encryption and primary perturbation on the data block.

[0134] The method of traversing the data block in the embodiment includes pre-order traversal, in-order traversal, post-order traversal, and level-order traversal. In each recursive level of the complete binary tree, the preset perturbation algorithm is executed on the current sub-complete binary tree to perform independent perturbation processing and complete primary perturbation.

[0135] Step 5: The data block after primary perturbation is converted into a parallel bit stream through serial-parallel conversion.

[0136] Step 6: Based on the constellation encryption factor and the constellation perturbation factor, the parallel bit stream is mapped to 16QAM and subjected to second traversal encryption and secondary perturbation according to the constellation perturbation factor.

[0137] In the embodiment, based on the traversal rule of the complete binary tree, when the parallel bit stream is mapped to 16QAM and subjected to second traversal encryption according to the constellation perturbation factor, the 16 constellation points are numbered first, and a complete binary tree with 16 nodes is constructed, then the nodes are reordered according to the selected traversal method to form a new mapping order, as shown in Figure 6 The embodiment can achieve perturbation encryption of the constellation diagram by replacing the original number with the perturbed number, so that the modulated signal has additional security, and the channel receiving end can restore the original constellation arrangement according to the shared traversal method information, ensuring the accuracy of demodulation.

[0138] Step 7: Convert the parallel bit stream after the second perturbation into a serial signal by using the discrete Fresnel inverse transform matrix, adding a prefix, and parallel-to-serial conversion.

[0139] Orthogonal chirp division multiplexing (OCD) is an advanced modulation scheme developed by combining improved traditional chirp spread spectrum (CSS) technology with orthogonal frequency division multiplexing (OFDM). Unlike traditional OFDM, OCD loads data symbols onto a set of... Modulation is performed on orthogonal chirped subcarriers. The orthogonal chirped subcarriers have good orthogonality with each other, thus enabling efficient signal transmission and demodulation.

[0140] In OCDM, the first The data symbol passes through the first Modulation is performed using orthogonal chirped subcarriers, and in conjunction with the first orthogonal chirped subcarrier in OFDM technology. The symbol passes through the first The modulation and demodulation principles of orthogonal chirped multiplexing (OCM) are similar to those of orthogonal frequency subcarrier modulation. Figure 2 As shown, where, This represents the 0th symbol. This represents the first symbol. This represents the (N-1)th symbol. This indicates the 0th chirped subcarrier. Indicates the first chirped subcarrier. This represents the (N-1)th chirped subcarrier. Indicates the current moment. This represents the integral of the transpose of the 0th chirped subcarrier. This represents the integral of the transpose of the first chirped subcarrier. Let represent the integral of the transpose of the (N-1)th chirped subcarrier. This indicates the 0th demodulated signal. This indicates the first demodulated signal. This represents the (N-1)th demodulated signal.

[0141] In this embodiment, OCDM modulation and demodulation are represented as follows:

[0142] ;

[0143] In the formula, Indicates the current time The modulation signal, This represents the total number of orthogonal chirped subcarriers. Indicates the modulated signal number 1 A symbol, Indicates the first A chirped subcarrier, Represents the entire OCDM symbol period. Indicates the first One demodulated signal. Indicates the first Transpose of a chirped subcarrier, express The differential.

[0144] In digital domain communication, the discrete Fresnel transform (DFnT) is commonly used to achieve OCDM modulation. DFnT originates from the integral transform in classical optics and is also the mathematical formula describing near-field optical diffraction. Its core expression is:

[0145] ;

[0146] In the formula, Indicates the current time The chirping parameter is Fresnel transform, Represents a vector. Represents the natural constant. Used to control the rate of change of the Fresnel transform frequency.

[0147] In this embodiment, the discrete Fresnel transformation matrix is ​​represented as:

[0148] ;

[0149] In the formula, Representing Fresnel transform The first in the matrix Line number The modulation signal of the item, Indicates the number of chirped subcarriers. Represents a vector. This indicates remainder operation.

[0150] The discrete Fresnel transformation matrix can be decomposed into: ,in This represents the discrete Fresnel transform matrix, used to transform a time-domain signal to the frequency domain. and These represent the first and second chirp matrices, respectively, which are responsible for modulation in the time and frequency domains. Each chirp signal has good orthogonality in the time and frequency domains, which can effectively combat multipath effects and frequency-selective fading in complex wireless communication environments.

[0151] In this embodiment, the first chirp matrix and the second chirp matrix are represented as follows:

[0152] ;

[0153] ;

[0154] wherein, represents the first th first chirp matrix, represents the first th second chirp matrix.

[0155] In the present embodiment, the digital modulation matrix of the OCDM is represented as:

[0156] ;

[0157] wherein, represents the digital modulation matrix of the OCDM, represents the discrete Fresnel inverse transform matrix, which is the complex conjugate transpose matrix of the discrete Fresnel transform matrix , represents the transpose, represents the modulation matrix.

[0158] In the present embodiment, the digital demodulation process using the digital modulation matrix is represented as:

[0159] ;

[0160] wherein, represents the matrix after digital demodulation.

[0161] In summary, the extra complexity of the digital demodulation process using the digital modulation matrix compared to the OFDM mainly comes from the operations of the first chirp matrix and the second chirp matrix and . From the perspective of matrix analysis, the first chirp matrix and the second chirp matrix and are sparse diagonal matrices, in which only the main diagonal elements are non-zero and the rest of the elements are zero. With the introduction of the first chirp matrix and the second chirp matrix, the extra operation complexity of each chirp carrier is O(2), and therefore the total extra complexity is O(2N), and the overall complexity increase is small.

[0162] Step 8: Perform up-conversion processing on the serial signal and transmit it to the transmission channel.

[0163] The following steps are performed at the channel receiving end:

[0164] Step 1: Receive the up-converted serial signal in the transmission channel and generate four groups of chaotic sequences identical to those at the channel transmitting end using the hyperchaotic system synchronization based on the same key initial value as the channel transmitting end.

[0165] Step 2: Use two groups of chaotic sequences to generate bit encryption factors and constellation encryption factors, and use another two groups of chaotic sequences to generate bit disturbance factors and constellation disturbance factors.

[0166] Step 3: Perform down-conversion processing on the up-converted serial signal to restore it to a serial signal.

[0167] Step 4: Convert the serial signal to a parallel bit stream through serial-parallel conversion, prefix removal operation, and discrete Fresnel transform matrix after secondary disturbance.

[0168] Step 5: Based on the constellation encryption factor and the constellation disturbance factor, perform 16QAM inverse mapping on the parallel bit stream and perform second traversal decryption and secondary disturbance according to the constellation disturbance factor.

[0169] Step 6: Convert the parallel bit stream to a primary disturbed data block through parallel-serial conversion.

[0170] Step 7: Based on the bit encryption factor and the bit disturbance factor, remove the primary disturbance and perform traversal decryption on the primary disturbed data block according to the bit encryption factor to restore the data block stored in the leaf node.

[0171] Step 8: According to the complete binary tree block structure, based on the hierarchical encoding routing information stored in the non-leaf node, combine the data block stored in the leaf node according to the same preset rule as the channel sending end to restore the original data.

[0172] The embodiment strictly calculates the key space of the encryption scheme to quantify the security performance of the transmission system, as shown in the following table: Figure 8 The key includes the initial value and control parameter of the Zhan-4D hyperchaotic system. If the step size is set to 0.001, through sensitivity test experiments, the key space can be strictly calculated by adding 1x10 -N to a single initial value or initial parameter, and then performing experiments to test whether the correct data can be successfully demodulated. Adjust the size of N until the node with a high bit error rate and a difference of one order of magnitude from complete demodulation is the key space. Then the key space can be calculated through experiments as (10 17 x 10 17 x 10 17 x 10 17 x 10 16 x 10 15 x 10 15 x 10 15 x 10 15 x 10 15 x 10 15 x 10 14 ) x 10 3 = 10 191Because the key space is large enough, even if the correct key is found, it takes a long time, thereby effectively preventing the hijacker from illegally obtaining the key.

[0173] Embodiment 4

[0174] Based on the same inventive concept as other embodiments, this embodiment introduces a channel sending end, comprising the following modules:

[0175] A data acquisition module is configured to acquire original data to be sent and a key initial value;

[0176] A factor generation module is configured to generate four groups of chaotic sequences based on the key initial value by using hyper-chaotic system synchronization, generate a bit encryption factor and a constellation encryption factor by using two groups of chaotic sequences, and generate a bit disturbance factor and a constellation disturbance factor by using the other two groups of chaotic sequences;

[0177] A data construction module is configured to divide the original data to be sent into an even number of data blocks according to a preset rule to construct a complete binary tree, wherein leaf nodes store data blocks, and non-leaf nodes store hierarchical encoding routing information;

[0178] A primary encryption module is configured to perform first traversal encryption and primary disturbance on the data blocks by using the bit encryption factor based on the bit encryption factor and the bit disturbance factor;

[0179] A time-frequency conversion module is configured to convert the data blocks after the primary disturbance into parallel bit streams through serial-parallel conversion;

[0180] A secondary encryption module is configured to perform QAM mapping on the parallel bit streams based on the constellation encryption factor and the constellation disturbance factor, and perform second traversal encryption and secondary disturbance according to the constellation disturbance factor;

[0181] A signal conversion module is configured to convert the parallel bit streams after the secondary disturbance into a serial signal through a discrete Fresnel inverse transform matrix and parallel-serial conversion;

[0182] A frequency conversion processing module is configured to perform up-conversion processing on the serial signal and transmit the serial signal to a transmission channel.

[0183] The specific function implementation of each module above can refer to the related content in the method of Embodiment 1 or Embodiment 3, and will not be described here.

[0184] Embodiment 5

[0185] Based on the same inventive concept as other embodiments, this embodiment introduces a channel receiving end, comprising the following modules:

[0186] The data acquisition module is configured to receive the up-converted serial signal in the transmission channel and generate four groups of chaotic sequences identical to those of the channel sending end based on the same key initial value as that of the channel sending end by using the hyper-chaotic system synchronization.

[0187] The factor generation module is configured to generate a bit encryption factor and a constellation encryption factor by using two groups of chaotic sequences, and generate a bit disturbance factor and a constellation disturbance factor by using the other two groups of chaotic sequences.

[0188] The frequency inverse processing module is configured to perform down-conversion processing on the up-converted serial signal to restore it to a serial signal.

[0189] The signal inverse conversion module is configured to restore the serial signal to a parallel bit stream after secondary disturbance by serial-parallel conversion and a discrete Fresnel transform matrix.

[0190] The secondary decryption module is configured to perform QAM inverse mapping on the parallel bit stream based on the constellation encryption factor and the constellation disturbance factor, and perform second traversal decryption and secondary disturbance according to the constellation disturbance factor.

[0191] The time-frequency inverse conversion module is configured to restore the parallel bit stream to a data block after primary disturbance by parallel-serial conversion.

[0192] The primary decryption module is configured to remove the primary disturbance and perform traversal decryption to restore the data block after primary disturbance to the data block stored in the leaf node based on the bit encryption factor and the bit disturbance factor according to the bit encryption factor.

[0193] The data reconstruction module is configured to combine and restore the data block stored in the leaf node to the original data according to the same preset rule as that of the channel sending end based on the hierarchical encoding routing information stored in the non-leaf node according to the complete binary tree block structure.

[0194] The up-converted serial signal is obtained by the signal transmission method of the first aspect.

[0195] The specific function implementation of each module is described in the related content of the method of Embodiment 2 or Embodiment 3, and is not repeated here.

[0196] In summary, the application effectively reduces the path complexity of data block traversal encryption by storing the hierarchical coding routing information of non-leaf nodes based on the hierarchical structure of the complete binary tree at the channel sending end, and significantly improves the ability to resist malicious eavesdropping and information tampering by using two independent traversal encryptions through the super chaotic sequence to generate bit encryption factors and constellation disturbance factors. Meanwhile, the introduction of the discrete Fresnel inverse transform matrix further optimizes the signal spectrum characteristics, while maintaining high anti-interference performance, improves the security level of the system, and is suitable for high security requirements in broadcast transmission scenarios such as passive optical networks, solving the problem of insufficient security protection in the actual application of the prior art.

[0197] At the channel receiving end, the hierarchical coding routing information stored by the non-leaf nodes based on the hierarchical structure of the complete binary tree ensures that the leaf node data blocks are accurately combined at the channel receiving end according to the same preset rules as the channel sending end, reducing the complexity and error rate of data recombination; and by using two independent traversal decryptions through the super chaotic sequence to generate bit encryption factors and constellation disturbance factors, the encryption process is completely reversed and aligned with the channel sending end, significantly improving the robustness of noise interference and malicious attacks. Meanwhile, the introduction of the discrete Fresnel transform matrix further optimizes the signal spectrum recovery accuracy through the strict correspondence with the inverse transform, while maintaining high demodulation efficiency, reducing the system security synchronization error rate, and is suitable for high reliable receiving requirements in broadcast transmission scenarios such as passive optical networks. Those skilled in the art should understand that the embodiments of the application can be provided as methods, systems, or computer program products. Therefore, the application can be in the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the application can be in the form of a computer program product implemented on one or more computer usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer usable program code.

[0198] The application is described with reference to flowcharts and / or block diagrams according to the embodiments of the application. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, and the combination of flows and / or blocks in the flowcharts and / or block diagrams can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing devices produce a device that implements the functions specified in the flowcharts and / or block diagrams. Figure 1 The device that implements the functions specified in one or more flows and / or blocks. Figure 1 The device that implements the functions specified in one or more flows and / or blocks.

[0199] These computer program instructions can also be stored in a computer readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer readable memory produce an article of manufacture including instructions which implement the flow Figure 1 The functions of a flow or multiple flows and / or a block or multiple blocks in conjunction with the disclosed embodiments, can be implemented as hardware logic circuits, such as an integrated circuit chip (e.g., an ASIC). Figure 1

[0200] These computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flow Figure 1 The functions of a flow or multiple flows and / or a block or multiple blocks in conjunction with the disclosed embodiments, can be implemented as hardware logic circuits, such as an integrated circuit chip (e.g., an ASIC). Figure 1

[0201] The above description of the disclosed embodiments is only illustrative of the application, and not intended to limit the scope of the application. The application is not limited to the specific embodiments described herein, but only by the claims that follow, and the full scope of equivalents thereof.​​

Claims

1. A signal transmission method, characterized by, The method is performed by a channel sending end and comprises: obtaining original data to be sent and a key initial value; generating four groups of chaotic sequences based on the key initial value by using a hyperchaotic system synchronization; generating a bit encryption factor, a bit disturbance factor, a constellation encryption factor and a constellation disturbance factor by using the four groups of chaotic sequences respectively; dividing the original data to be sent into an even number of data blocks according to a preset rule to construct a complete binary tree, wherein leaf nodes store the data blocks and non-leaf nodes store routing information of hierarchical encoding; based on the bit encryption factor and the bit disturbance factor, performing first traversal encryption and primary disturbance on the data blocks by using the bit encryption factor; converting the data blocks after the primary disturbance into parallel bit streams through serial-parallel conversion; based on the constellation encryption factor and the constellation disturbance factor, performing QAM mapping on the parallel bit streams and second traversal encryption and secondary disturbance according to the constellation disturbance factor; converting the parallel bit streams after the secondary disturbance into a serial signal through a discrete Fresnel inverse transform matrix and parallel-serial conversion; performing up-conversion processing on the serial signal and transmitting the serial signal to a transmission channel.

2. The signal transmission method of claim 1, wherein, The hyperchaotic system comprises a Zhan-4D hyperchaotic system, and the Zhan-4D hyperchaotic system is represented as: ； wherein denotes the first derivative of the state variable of the Zhan-4D hyperchaotic system along the horizontal axis, denotes the first derivative of the state variable of the Zhan-4D hyperchaotic system along the vertical axis, denotes the first derivative of the state variable of the Zhan-4D hyperchaotic system along the vertical axis, denotes the first derivative of the state feedback control parameter of the Zhan-4D hyperchaotic system, denotes the first derivative of the first system parameter of the Zhan-4D hyperchaotic model, denotes the first derivative of the second system parameter of the Zhan-4D hyperchaotic model, denotes the first derivative of the third system parameter of the Zhan-4D hyperchaotic model, denotes the first derivative of the fourth system parameter of the Zhan-4D hyperchaotic model, denotes the first derivative of the fifth system parameter of the Zhan-4D hyperchaotic model, denotes the first derivative of the sixth system parameter of the Zhan-4D hyperchaotic model, denotes the first derivative of the seventh system parameter of the Zhan-4D hyperchaotic model, denotes the first derivative of the eighth system parameter of the Zhan-4D hyperchaotic model, wherein , , , , , , and co-control the chaotic behavior of the Zhan-4D hyperchaotic system.​​​​ 3. The signal transmission method of claim 2, wherein, The method of generating the bit encryption factor, the bit disturbance factor, the constellation encryption factor and the constellation disturbance factor by using the four groups of chaotic sequences respectively comprises: ； wherein denotes a bit encryption factor, denotes a bit perturbation factor, denotes a constellation encryption factor, denotes a constellation perturbation factor, denotes a remainder operation, denotes an operation function that rounds towards negative infinity, denotes a first chaotic sequence of the four sets of chaotic sequences, denotes a second chaotic sequence of the four sets of chaotic sequences, denotes a third chaotic sequence of the four sets of chaotic sequences, denotes a fourth chaotic sequence of the four sets of chaotic sequences.

4. The signal transmission method of claim 1, wherein, The method further comprises: performing the following recursive operation on the data blocks stored in each leaf node of the complete binary tree: dividing the current data block into an even number of sub-data blocks according to the same preset rule; constructing a corresponding complete binary tree as a sub-complete binary tree for each sub-data block; stopping the recursion until the data block reaches a minimum granularity, wherein the minimum granularity is a bit data stream.

5. The signal transmission method of claim 4, wherein, The primary disturbance or the secondary disturbance comprises: in each recursive level of the complete binary tree, performing independent disturbance processing on the current sub-complete binary tree by using a preset disturbance algorithm.

6. The signal transmission method of claim 1, wherein, The method of performing traversal on the data block comprises: pre-order traversal, in-order traversal, post-order traversal and level-order traversal.

7. A signal receiving method characterized by comprising: The method is performed by a channel receiving end and comprises: receiving the serial signal after the up-conversion processing in the transmission channel and generating four groups of chaotic sequences identical to those of the channel sending end by using a hyperchaotic system synchronization based on a key initial value identical to that of the channel sending end; generating the bit encryption factor and the constellation encryption factor by using two groups of chaotic sequences; generating the bit disturbance factor and the constellation disturbance factor by using the other two groups of chaotic sequences; performing down-conversion processing on the serial signal after the up-conversion processing to restore the serial signal; restoring the serial signal into the parallel bit streams after the secondary disturbance through serial-parallel conversion and a discrete Fresnel transform matrix; based on the constellation encryption factor and the constellation disturbance factor, performing QAM inverse mapping on the parallel bit streams and second traversal decryption and secondary disturbance according to the constellation disturbance factor; restoring the parallel bit streams into the data blocks after the primary disturbance through parallel-serial conversion; based on the bit encryption factor and the bit disturbance factor, removing the primary disturbance and performing traversal decryption on the data blocks after the primary disturbance according to the bit encryption factor to restore the data blocks stored in the leaf nodes; and According to the complete binary tree block structure, based on the hierarchical coding routing information stored by the non-leaf nodes, the data blocks stored by the leaf nodes are combined and recovered into the original data according to the same preset rule as the channel sending end.

8. The signal receiving method according to claim 7, wherein The discrete Fresnel transform matrix is expressed as: ； wherein represents a Fresnel transform the modulation signal of the entry in the matrix in the row and the entry in the matrix, represents the number of chirped subcarriers, represents a vector, represents a remainder operation.

9. A channel transmitting end, characterized in that, The method comprises the following modules: The data acquisition module is configured to acquire original data to be sent and a key initial value. The factor generation module is configured to generate four groups of chaotic sequences by using hyper-chaotic system synchronization based on the key initial value, generate a bit encryption factor and a constellation encryption factor by using two groups of chaotic sequences, and generate a bit disturbance factor and a constellation disturbance factor by using the other two groups of chaotic sequences. The data construction module is configured to divide the original data to be sent into an even number of data blocks according to a preset rule to construct a complete binary tree, wherein leaf nodes store data blocks, and non-leaf nodes store hierarchical coding routing information. The primary encryption module is configured to perform first traversal encryption and primary disturbance on the data blocks by using the bit encryption factor based on the bit encryption factor and the bit disturbance factor. The time-frequency conversion module is configured to convert the data blocks after the primary disturbance into parallel bit streams through serial-parallel conversion. The secondary encryption module is configured to perform QAM mapping on the parallel bit streams based on the constellation encryption factor and the constellation disturbance factor, and perform second traversal encryption and secondary disturbance according to the constellation disturbance factor. The signal conversion module is configured to convert the parallel bit streams after the secondary disturbance into a serial signal through a discrete Fresnel inverse transform matrix and parallel-serial conversion. The frequency conversion processing module is configured to perform up-conversion processing on the serial signal and transmit the serial signal to a transmission channel.

10. A channel receiving end, characterized by, The data acquisition module is configured to receive the serial signal after the up-conversion processing in the transmission channel and generate four groups of chaotic sequences identical to those of the channel sending end by using hyper-chaotic system synchronization based on the same key initial value as the channel sending end. The factor generation module is configured to generate a bit encryption factor and a constellation encryption factor by using two groups of chaotic sequences, and generate a bit disturbance factor and a constellation disturbance factor by using the other two groups of chaotic sequences. The frequency inverse processing module is configured to perform down-conversion processing on the serial signal after the up-conversion processing to recover the serial signal. The signal inverse conversion module is configured to recover the parallel bit streams after the secondary disturbance into the serial signal through serial-parallel conversion and a discrete Fresnel transform matrix. The secondary decryption module is configured to perform QAM inverse mapping on the parallel bit streams based on the constellation encryption factor and the constellation disturbance factor, and perform second traversal decryption and secondary disturbance according to the constellation disturbance factor. The time-frequency inverse conversion module is configured to recover the data blocks after the primary disturbance into the data blocks after the primary disturbance by using parallel-serial conversion. The primary decryption module is configured to remove the primary disturbance from the data blocks after the primary disturbance and perform traversal decryption to recover the data blocks stored by the leaf nodes according to the bit encryption factor based on the bit encryption factor and the bit disturbance factor. The data reconstruction module is configured to recover the data blocks stored by the leaf nodes into the original data according to the same preset rule as the channel sending end based on the hierarchical coding routing information stored by the non-leaf nodes according to the complete binary tree block structure. The serial signal after the up-conversion processing is obtained by the signal transmission method in any one of claims 1 to 6. ​

Images