A chaotic polar encoding transmission method and receiving method based on packet multicarrier modulation, a transmission end, a receiving end and method

Abstract

The application discloses a chaos polarization encoding sending method based on packet multicarrier modulation in the technical field of communication, a receiving method, a sending end, a receiving end and methods. The method comprises the following steps: after original data is blocked, the original data is encoded to obtain encoded data, wherein, in the encoding process, the reliability of each bit position is determined according to the channel characteristics, the most reliable part of the bit position is selected to place an information bit, and other positions are set as frozen bits; the encoded data is QPSK modulated to obtain a modulated signal, a disturbance factor is generated through a four-dimensional chaos system, the frozen matrix and the modulated signal are encrypted to obtain an encrypted signal; the initial value of the four-dimensional chaos system obtained is mixed with the encrypted signal to obtain transmission information, and the transmission information is transmitted through orthogonal frequency division multiplexing technology. The application realizes the optimal transmission rate through polarization encoding; and the security transmission of a dynamic key is realized through a chaos encryption technology, and the safety of signal transmission is ensured.

Description

Technical Field

[0001] This invention relates to a chaotic polarization coding transmission method, a receiving method, a transmitting end, a receiving end, and a method based on grouped multicarrier modulation, belonging to the field of communication technology. Background Technology

[0002] In recent years, with the rapid development of the internet society, emerging technologies based on underlying communication technologies, such as big data, cloud computing, the Internet of Things, high-definition video, augmented reality, and virtual reality, have been increasingly applied. Network traffic has exploded, and the demand for high-capacity, low-latency, and long-distance high-speed communication technologies will increase year by year. However, the transmission rate of communication systems is always limited by the Shannon limit. In existing technologies, error correction coding can effectively improve the channel transmission rate by encoding and modulating signals, such as soft detection forward error correction (FEC) coding. Polar codes are a newly proposed FEC coding method in recent years. This coding can effectively reduce the bit error rate of the system with relatively low complexity, thus approaching the Shannon limit.

[0003] However, due to the non-asymptotic structure of classical coding construction methods, channel reliability defects may occur, and communication security is difficult to guarantee. How to ensure the security of the transmission system based on physical layer encryption schemes while ensuring the system transmission rate is an important research direction in the field of communication. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the defects of the prior art and provide a chaotic polarization coding transmission method, a receiving method, a transmitting end, a receiving end and the method based on grouped multicarrier modulation.

[0005] To solve the above-mentioned technical problems, the present invention is implemented using the following technical solution.

[0006] In a first aspect, the present invention discloses a chaotic polarization coding transmission method based on grouped multicarrier modulation, comprising: The original data is divided into blocks and then polar-coded to obtain coded data. During the coding process, the reliability of each bit position is determined according to the channel characteristics. The most reliable bits are selected to place information bits, and the other positions are set as frozen bits. The encoded data is QPSK modulated to obtain a modulated signal. A perturbation factor is generated through a four-dimensional chaotic system to encrypt the frozen matrix and the modulated signal to obtain an encrypted signal. The frozen matrix is ​​the position information of the frozen bits after polarization encoding. The initial value of the obtained four-dimensional chaotic system is mixed with the encrypted signal to obtain transmission information, which is then transmitted using orthogonal frequency division multiplexing (OFDM) technology.

[0007] Furthermore, the encoding is a chaotic polarization encoding, and its polarization encoded signal representation is as follows: ; In the formula, x This represents a polarization-coded signal; u Indicates the signal to be encoded; F n This indicates that the polar code length is 2. n The construction matrix, n It is a positive integer; ; In the formula, For Kronecker product, F Represents the fundamental polarization matrix. .

[0008] Furthermore, the step of generating a perturbation factor through a four-dimensional chaotic system to encrypt the frozen matrix and the modulated signal to obtain an encrypted signal includes: Four sets of chaotic sequences were generated using a four-dimensional hyperchaotic model. x n , y n , z n , l n The four-dimensional hyperchaotic model is represented as: ; In the formula, X, Y, Z, and L are state variables, and a, b, c, d, and e are parameters of the four-dimensional hyperchaotic model. , , , The derivatives of X, Y, Z, and L; Through chaotic sequences ( x n , y n , z n , l n The perturbation factor is generated, and the frozen matrix, the modulated signal constellation, the frozen bits, and the subcarriers are encrypted to obtain the encrypted signal.

[0009] Furthermore, the encryption rules are as follows: ; In the formula, mod() is the remainder function; sort The parentheses sort the array matrix in ascending order and return the sorted array. TIt is the transpose matrix; X n The first scrambling sequence is used as an angle perturbation factor for constellation rotation to perturb the entire signal; Y n This is the second scrambling sequence, used as a perturbation factor for the frozen matrix; Z n This is the third scrambling sequence, used as a perturbation factor for the filling bits on the frozen bits; L n This is the fourth scrambling sequence, used as a perturbation factor for the subcarrier position.

[0010] Further, the initial value of the acquired four-dimensional chaotic system is mixed with the encrypted signal to obtain the information to be transmitted, and the information to be transmitted is transmitted using orthogonal frequency division multiplexing (OFDM) technology, including: The initial values ​​X(0), Y(0), Z(0), and L(0) of the 16-bit decimal four-dimensional chaotic system are converted into binary numbers to obtain 256-bit key information; The transmitted information is mixed in groups of 30-bit encrypted signals and 4-bit key information. The 4-bit key information is then modulated into groups by corresponding the positions of silent subcarriers using orthogonal frequency division multiplexing (OFDM) technology. The silent subcarriers are then filled into the transmitted information for transmission.

[0011] Secondly, the present invention also discloses a chaotic polarization coding transmitter based on group multicarrier modulation, comprising: The encoding module is used to divide the original data into blocks and then perform polar coding to obtain encoded data. During the encoding process, the reliability of each bit position is determined according to the channel characteristics, the most reliable bits are selected to place information bits, and the other positions are set as frozen bits. An encryption module is used to perform QPSK modulation on the encoded data to obtain a modulated signal, generate a perturbation factor through a four-dimensional chaotic system, and encrypt the freeze matrix and the modulated signal to obtain an encrypted signal; the freeze matrix is ​​the position information of the frozen bits after polarization encoding. The transmission module is used to mix the acquired initial value of the four-dimensional chaotic system with the encrypted signal to obtain transmission information, and to transmit the transmission information through orthogonal frequency division multiplexing technology.

[0012] Thirdly, the present invention also discloses a chaotic polarization coding reception method based on group multicarrier modulation, comprising: The transmission information described in any one of claims 1-5 is demodulated using orthogonal frequency division multiplexing (OFDM) technology. The key is separated from the transmission information to recover the signal. After sequentially undergoing QPSK demodulation and separation of frozen bits, the original data is obtained.

[0013] Furthermore, the step of separating the key from the transmitted information to recover the signal includes: The power in the optical fiber is measured using an optical power meter to obtain the location information of the silent subcarrier. Based on the position information of the silent subcarrier, the initial value of the corresponding four-dimensional chaotic system is extracted. After chaotic mapping based on the initial value of the four-dimensional chaotic system, the first scrambling sequence X, the second scrambling sequence Y, the third scrambling sequence Z, and the fourth scrambling sequence L are recovered. The data at the receiving end is decoded and recovered based on the first scrambling sequence X, the second scrambling sequence Y, the third scrambling sequence Z, and the fourth scrambling sequence L.

[0014] Fourthly, the present invention also discloses a chaotic polarization-coded receiver based on grouped multicarrier modulation, comprising: The decoding module is used to demodulate the transmitted information sent in claim 6 using orthogonal frequency division multiplexing technology, and to separate the key from the transmitted information to recover the signal; The demodulation and separation module is used to sequentially perform QPSK demodulation and freeze bit separation operations on the decoded and recovered signal to obtain the original data.

[0015] Fifthly, the present invention also discloses a chaotic polarization coding method based on grouped multicarrier modulation, comprising: At the transmitting end, the original data is divided into blocks and then polar-coded to obtain encoded data. During the encoding process, the reliability of each bit position is determined according to the channel characteristics. The most reliable bits are selected to place information bits, and the other positions are set as frozen bits. The encoded data is QPSK modulated to obtain a modulated signal. A perturbation factor is generated through a four-dimensional chaotic system to encrypt the frozen matrix and the modulated signal to obtain an encrypted signal. The frozen matrix is ​​the position information of the frozen bits after polarization encoding. The initial value of the obtained four-dimensional chaotic system is mixed with the encrypted signal to obtain transmission information, which is then transmitted using orthogonal frequency division multiplexing technology. At the receiving end, the transmitted information is demodulated using orthogonal frequency division multiplexing (OFDM) technology. The key is separated from the transmitted information to recover the signal. After QPSK demodulation and separation of frozen bits, the original data is obtained.

[0016] The beneficial effects achieved by this invention are as follows: This invention polarizes the channel through channel combining and channel splitting to achieve the optimal transmission rate, thus constructing a high-speed communication transmission system. Furthermore, this invention utilizes chaotic encryption technology, perturbing the signal and decryption matrix with encryption factors, and employs group multicarrier modulation technology to achieve secure transmission of dynamic keys, ensuring the security of signal transmission. Attached Figure Description

[0017] Figure 1 This is a flowchart of a chaotic polarization coding method based on grouped multicarrier modulation; Figure 2 This is a schematic diagram of the polarization coding section. Figure 3 This is a schematic diagram of a polar code with a length of 2; Figure 4 This is a schematic diagram of a polar code with a length of 4; Figure 5 This is a schematic diagram of channel polarization; Figure 6 It is a phase diagram of a chaotic system; Figure 7 This is a schematic diagram of grouped multicarrier modulation. Detailed Implementation

[0018] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.

[0019] Example 1: This example introduces a chaotic polarization coding transmission method based on group multicarrier modulation, including: The original data is divided into blocks and then polar-coded to obtain coded data. During the coding process, the reliability of each bit position is determined according to the channel characteristics. The most reliable bits are selected to place information bits, and the other positions are set as frozen bits. The encoded data is modulated using QPSK (Quadrature Phase Shift Keying) to obtain a modulated signal. A perturbation factor is generated through a four-dimensional chaotic system to encrypt the frozen matrix and the modulated signal, resulting in an encrypted signal. The frozen matrix contains the position information of the frozen bits after polarization encoding. The initial value of the obtained four-dimensional chaotic system is mixed with the encrypted signal to obtain transmission information, which is then transmitted using orthogonal frequency division multiplexing (OFDM) technology.

[0020] The encoding is a chaotic polarization encoding, and its polarization encoded signal representation is as follows: ; In the formula, x This represents a polarization-coded signal; u Indicates the signal to be encoded; F n This indicates that the polar code length is 2. n The construction matrix; n It is a positive integer; ; In the formula, The product is the Kronecker product, where F represents the fundamental polarization matrix. .

[0021] The process of generating a perturbation factor through a four-dimensional chaotic system to encrypt the frozen matrix and the modulated signal to obtain an encrypted signal includes: Four sets of chaotic sequences were generated using a four-dimensional hyperchaotic model. The four-dimensional hyperchaotic model is represented as: ; In the formula, X, Y, Z, and L are state variables, and a, b, c, d, and e are parameters of the four-dimensional hyperchaotic model. , , , The derivatives of X, Y, Z, and L; Through chaotic sequences ( The perturbation factor is generated, and the frozen matrix, the modulated signal constellation, the frozen bits, and the subcarriers are encrypted to obtain the encrypted signal.

[0022] The encryption rules are as follows: ; In the formula, mod() is the modulo function; sort() sorts the array matrix in ascending order and returns the sorted array; T is the transpose matrix; X n The first scrambling sequence is used as an angle perturbation factor for constellation rotation to perturb the entire signal; Y n Z is the second scrambling sequence, used as a perturbation factor for the frozen matrix. n This is the third scrambling sequence, used as a perturbation factor for the fill bits on the frozen bits; L n This is the fourth scrambling sequence, used as a perturbation factor for the subcarrier position; Chaotic sequences generated for a chaotic model.

[0023] The process of mixing the initial value of the acquired four-dimensional chaotic system with the encrypted signal to obtain the information to be transmitted, and transmitting the information to be transmitted using orthogonal frequency division multiplexing (OFDM) technology, includes: The initial values ​​X(0), Y(0), Z(0), and L(0) of the 16-bit decimal four-dimensional chaotic system are converted into binary numbers to obtain 256-bit key information; The transmitted information is mixed in groups of 30-bit encrypted signals and 4-bit key information. The 4-bit key information is then modulated into groups by corresponding the positions of silent subcarriers using orthogonal frequency division multiplexing (OFDM) technology. The silent subcarriers are then filled into the transmitted information for transmission.

[0024] Example 2, based on the same inventive concept as Example 1, introduces a chaotic polarization coding reception method based on group multicarrier modulation, including: The transmitted information described in Example 1 is demodulated using orthogonal frequency division multiplexing (OFDM) technology. The key is separated from the transmitted information to recover the signal. After QPSK demodulation and separation of frozen bits, the original data is obtained.

[0025] The step of separating the key from the transmitted information to recover the signal includes: The power in the optical fiber is measured using an optical power meter to obtain the location information of the silent subcarrier. Based on the position information of the silent subcarrier, the initial value of the corresponding four-dimensional chaotic system is extracted. After chaotic mapping based on the initial value of the four-dimensional chaotic system, the first scrambling sequence X, the second scrambling sequence Y, the third scrambling sequence Z, and the fourth scrambling sequence L are recovered. The data at the receiving end is decoded and recovered based on the first scrambling sequence X, the second scrambling sequence Y, the third scrambling sequence Z, and the fourth scrambling sequence L.

[0026] Example 3, based on the same inventive concept as other examples, introduces a chaotic polarization coding transmitter based on group multicarrier modulation, comprising: The encoding module is used to divide the original data into blocks and then perform polar coding to obtain encoded data. During the encoding process, the reliability of each bit position is determined according to the channel characteristics, the most reliable bits are selected to place information bits, and the other positions are set as frozen bits. An encryption module is used to perform QPSK modulation on the encoded data to obtain a modulated signal, and to generate a perturbation factor through a four-dimensional chaotic system to encrypt the frozen matrix and the modulated signal to obtain an encrypted signal. The transmission module is used to mix the acquired initial value of the four-dimensional chaotic system with the encrypted signal to obtain transmission information, and to transmit the transmission information through orthogonal frequency division multiplexing technology.

[0027] Example 4, based on the same inventive concept as other examples, introduces a chaotic polarization coding receiver based on group multicarrier modulation, comprising: The decoding module is used to demodulate the transmitted information sent by the transmitter in Example 3 using orthogonal frequency division multiplexing technology, and to separate the key from the transmitted information to recover the signal; The demodulation and separation module is used to sequentially perform QPSK demodulation and freeze bit separation operations on the decoded and recovered signal to obtain the original data.

[0028] Example 5, based on the same inventive concept as other examples, introduces a chaotic polarization coding method based on grouped multicarrier modulation, including: like Figure 1 and Figure 2 As shown, the original data is divided into blocks and encoded. Based on channel characteristics, the reliability of each bit position is determined, and the most reliable bits are selected to place the information bits, while the others are designated as frozen bits. Then, the encoded data is QPSK modulated, and a perturbation factor is generated using a four-dimensional chaotic system to encrypt the frozen matrix and the modulated signal. Since the chaotic system only needs to transmit the initial system value to recover the entire key, the initial chaotic system value can be mixed with the encrypted signal using block multicarrier modulation technology to achieve dynamic key transmission. Subsequently, the signal is transmitted using Orthogonal Frequency Division Multiplexing (OFDM). At the receiving end, after OFDM demodulation, the key is separated from the signal to recover the signal. After further demodulation and separation of frozen bits, the original data is recovered, achieving high-security and high-speed transmission.

[0029] (1) The chaotic polarization coding part in this embodiment includes: First, the raw input bits are divided into blocks, each block being K bits, and then polar-coded. For example... Figure 3 As shown, a polar code of length N=2 is the basic component of polar coding, where (u1, u2) represents the input sequence and (x1, x2) represents the encoded sequence. This represents modulo-2 addition. The entire process can be represented using a generator matrix. express.

[0030] The length is N=2 n The polar code is an extension of the polar code of length 2, with a length of N=2. n The polar code is an extension of the 2-bit polar code; that is, the polar code (x1, x2) generated by the 2-bit polar code is treated as (u1, u2) of another 2-bit polar code. The polarization process of a 4-bit polar code is as follows: Figure 4 As shown.

[0031] When N=4, its construction matrix can be represented as This leads to the conclusion that the code length N=2. n hour, , For the Kronecker product, the signal can be represented as .

[0032] The above construction method allows for the merging of multiple channels into a single composite channel, or the recursive transformation splitting of a composite channel into N sub-channels. After merging multiple independent channels, they are split into two types of sub-channels: one type is completely reliable (channel capacity approaches 1), and the other is completely unreliable (channel capacity approaches 0). Information bits are transmitted only through the high-reliability sub-channels, thus achieving efficient and reliable communication. Figure 5 For N=214 A schematic diagram of channel capacity at that time.

[0033] In the encoding process of polar codes, information bits are placed only at the positions corresponding to high-reliability channels, while the positions of low-reliability channels are fixed to predefined values ​​(usually 0). These fixed positions are called frozen bits. During the encoding process, a freeze matrix can be generated to mark the positions of frozen bits in the codeword. The freeze matrix can assist the receiver in decoding and reduce computational complexity. For decoding, SCL (Serial Cancellation List) decoding is used. SCL is an efficient decoding algorithm for polar codes. It dynamically maintains multiple candidate paths (the number is determined by the preset list size) during the decoding process, performs path splitting and pruning bit by bit, and retains the optimal path set to reduce the risk of single-path error propagation. Specifically, when decoding to a non-frozen bit, SCL tries both 0 and 1 values ​​for each path, generates double the paths, sorts them by path metric (such as the accumulated log-likelihood ratio), and retains only the top K (K is the preset list size) optimal paths. Finally, the most reliable path in the list is selected as the decoding result. Compared with basic SC decoding, SCL significantly improves error correction capability and reduces complexity.

[0034] After channel polarization is completed, the entire signal is encrypted. This patent utilizes a four-dimensional hyperchaotic model to encrypt the signal, as shown below: ; Where X, Y, Z, and L are state variables, and a, b, c, d, and e are system parameters. When a = 3.04, b = 1.02, c = 9.02, d = 1, and e = 2.02, the system has two positive Lyapunov exponents, proving that the system is a hyperchaotic system. The initial values ​​of the chaotic system are set as: X(0) = 0.1121314151617181, Y(0) = 0.1222324252627282. Z(0) = 0.1323334353637383, L(0) = 0.1323334353637383. Four chaotic sequences can be generated after chaotic mapping. This invention generates a perturbation factor using a chaotic sequence, and then encrypts the signal constellation, the freeze matrix, the freeze bits, and the subcarriers, respectively. Figure 6 As shown, x y, z, l are chaotic sequences ( Phase diagram of ).

[0035] The specific encryption rules are as follows: ; Here, mod() is the modulo function, which multiplies each chaotic sequence by 10. 10The scrambling sequence is generated by selecting the 10th decimal place of four sets of keys to improve the randomness of subcarrier and symbol masking. `sort()` sorts the array matrix in ascending order and returns the sorted array; the letter T represents the transpose matrix. As shown in the formula, we multiply the modulo matrix with the sorted transpose matrix to obtain four scrambling matrices, with orders representing the number of subcarriers and symbols for high-power signals and low-power signals, respectively. Each row and column of this matrix contains one 1, and the remaining elements are all marked as 0. Extracting the positions of the 1s from the four matrices yields four scrambling sequences. The scrambling sequence... X n The angle perturbation factor used for constellation rotation will be used to perturb the entire signal and scramble the sequence. Y n As a perturbation factor for the frozen matrix, the scrambled sequence Z n As a perturbation factor for the filling bits on the frozen bits, L n As a perturbation factor for the subcarrier position, x n , y n , z n , l n A chaotic sequence generated for a chaotic model.

[0036] (2) The dynamic key transmission part in this embodiment: Regarding key transmission, this patent employs block multicarrier modulation (BMC) technology to mask the key. Unlike traditional methods where the receiver is assumed to know the key, this patent transmits the key and signal together to the receiver via BMC. A schematic diagram of the BMC technology is shown below. Figure 7 As shown.

[0037] In OFDM transmission systems, multiple parallel subcarriers are used to transmit data. By muting some subcarriers, additional information can be transmitted using the position of the muted subcarriers within the signal, adding a new degree of freedom to signal transmission. Packet multicarrier modulation utilizes the positional information of subcarriers during transmission to represent and transmit information. By using a portion of the transmitted information as subcarrier keying, the activation and muting states of the subcarriers are controlled to modulate the additional information. In QPSK modulation, 16 subcarriers form a group. In traditional transmission methods, each subcarrier can transmit 2 bits of data, for a total of 32 bits. Figure 7 As shown in (a); if one group of subcarriers is silenced, the positions of the silenced subcarriers can be 16 = 2. 4 This arrangement can transmit 4 bits of data, for a total of 15 × 2 + 4 = 34 bits of data, such as... Figure 7 As shown in (b). If both sets of subcarriers are silenced, then... This arrangement can transmit 6 bits of data, for a total of 14 × 2 + 6 = 34 bits of data, such as... Figure 7 As shown in (c).

[0038] The key concealment method of this patent involves first converting the initial key values ​​X(0), Y(0), Z(0), and L(0) into binary numbers. Since each key has 16 bits, the total binary number is 256 bits. The transmission signal is mixed in groups of 30 bits of transmission information and 4 bits of key information. The 4 bits of key information are then mapped to the positions of silent subcarriers and grouped for multi-carrier modulation. The silent subcarriers are then filled into the information to be transmitted. This achieves dynamic key transmission using only a very small portion of the spectrum. Even if the initial key value is temporarily changed, it can still be synchronized to the receiving end. Furthermore, if a misalignment during demodulation causes a single binary bit error, the original data cannot be recovered. Therefore, this scheme has extremely high security performance.

[0039] During the key extraction process at the receiving end, the power in the optical fiber is first measured directly using an optical power meter to obtain the location information of the silent subcarrier. Then, based on this location information, the corresponding initial key value can be extracted. After chaotic mapping, the scrambled sequence (X) can be recovered. n ,Y n Z n ,L n ), used to decode and recover data from the receiving end.

[0040] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied 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.

[0041] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0042] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0043] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0044] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A chaotic polar coding transmission method based on grouped multicarrier modulation, characterized in that, include: The original data is divided into blocks and then polar-coded to obtain coded data. During the coding process, the reliability of each bit position is determined according to the channel characteristics. The most reliable bits are selected to place information bits, and the other positions are set as frozen bits. The encoded data is QPSK modulated to obtain a modulated signal. A perturbation factor is generated through a four-dimensional chaotic system to encrypt the frozen matrix and the modulated signal to obtain an encrypted signal. The frozen matrix is ​​the position information of the frozen bits after polarization encoding. The initial value of the obtained four-dimensional chaotic system is mixed with the encrypted signal to obtain transmission information, which is then transmitted using orthogonal frequency division multiplexing technology. The process of generating a perturbation factor through a four-dimensional chaotic system to encrypt the frozen matrix and the modulated signal to obtain an encrypted signal includes: Four sets of chaotic sequences (x) were generated using a four-dimensional hyperchaotic model. n , y n , z n , l n The four-dimensional hyperchaotic model is represented as: ； In the formula, X, Y, Z, and L are state variables, and a, b, c, d, and e are parameters of the four-dimensional hyperchaotic model. , , , The derivatives of X, Y, Z, and L; Through chaotic sequence (x) n , y n , z n , l n The perturbation factor is generated, and the frozen matrix, the modulated signal constellation, the frozen bits, and the subcarriers are encrypted to obtain the encrypted signal. The encryption rules are as follows: ； In the formula, mod() is the modulo function; sort() sorts the array matrix in ascending order and returns the sorted array; T is the transpose matrix; X n The first scrambling sequence is used as an angle perturbation factor for constellation rotation to perturb the entire signal; Y n Z is the second scrambling sequence, used as a perturbation factor for the frozen matrix. n This is the third scrambling sequence, used as a perturbation factor for the fill bits on the frozen bits; L n This is the fourth scrambling sequence, used as a perturbation factor for the subcarrier position.

2. The chaotic polarization coding transmission method based on group multicarrier modulation according to claim 1, characterized in that, The encoding is a chaotic polarization encoding, and its polarization encoded signal representation is as follows: ； In the formula, x represents the polarization-coded signal; u represents the signal to be encoded; F n This indicates that the polar code length is 2. n The construction matrix, where n is a positive integer; ； In the formula, The product is the Kronecker product, where F represents the fundamental polarization matrix. .

3. The chaotic polarization coding transmission method based on group multicarrier modulation according to claim 1, characterized in that, The process of mixing the initial value of the acquired four-dimensional chaotic system with the encrypted signal to obtain the information to be transmitted, and transmitting the information to be transmitted using orthogonal frequency division multiplexing (OFDM) technology, includes: The initial values ​​X(0), Y(0), Z(0), and L(0) of the 16-bit decimal four-dimensional chaotic system are converted into binary numbers to obtain 256-bit key information; The transmitted information is mixed in groups of 30-bit encrypted signals and 4-bit key information. The 4-bit key information is then modulated into groups by corresponding the positions of silent subcarriers using orthogonal frequency division multiplexing (OFDM) technology. The silent subcarriers are then filled into the transmitted information for transmission.

4. A chaotic polarization coding transmitter based on grouped multicarrier modulation, characterized in that, include: The encoding module is used to divide the original data into blocks and then perform polar coding to obtain encoded data. During the encoding process, the reliability of each bit position is determined according to the channel characteristics, the most reliable bits are selected to place information bits, and the other positions are set as frozen bits. An encryption module is used to perform QPSK modulation on the encoded data to obtain a modulated signal, generate a perturbation factor through a four-dimensional chaotic system, and encrypt the freeze matrix and the modulated signal to obtain an encrypted signal; the freeze matrix is ​​the position information of the frozen bits after polarization encoding. The transmission module is used to mix the acquired initial value of the four-dimensional chaotic system with the encrypted signal to obtain transmission information, and to transmit the transmission information through orthogonal frequency division multiplexing technology. The process of generating a perturbation factor through a four-dimensional chaotic system to encrypt the frozen matrix and the modulated signal to obtain an encrypted signal includes: Four sets of chaotic sequences (x) were generated using a four-dimensional hyperchaotic model. n , y n , z n , l n The four-dimensional hyperchaotic model is represented as: ； In the formula, X, Y, Z, and L are state variables, and a, b, c, d, and e are parameters of the four-dimensional hyperchaotic model. , , , The derivatives of X, Y, Z, and L; Through chaotic sequence (x) n , y n , z n , l n The perturbation factor is generated, and the frozen matrix, the modulated signal constellation, the frozen bits, and the subcarriers are encrypted to obtain the encrypted signal. The encryption rules are as follows: ； In the formula, mod() is the modulo function; sort() sorts the array matrix in ascending order and returns the sorted array; T is the transpose matrix; X n The first scrambling sequence is used as an angle perturbation factor for constellation rotation to perturb the entire signal; Y n Z is the second scrambling sequence, used as a perturbation factor for the frozen matrix. n The third scrambling sequence is used as a perturbation factor for the fill bits on the frozen bits; L n This is the fourth scrambling sequence, used as a perturbation factor for the subcarrier position.

5. A chaotic polarization coding reception method based on grouped multicarrier modulation, characterized in that, include: The transmission information described in any one of claims 1-3 is demodulated using orthogonal frequency division multiplexing (OFDM) technology. The key is separated from the transmission information to recover the signal. After sequentially undergoing QPSK demodulation and separation of frozen bits, the original data is obtained.

6. The chaotic polarization coding reception method based on group multicarrier modulation according to claim 5, characterized in that, The step of separating the key from the transmitted information to recover the signal includes: The power in the optical fiber is measured using an optical power meter to obtain the location information of the silent subcarrier. Based on the position information of the silent subcarrier, the initial value of the corresponding four-dimensional chaotic system is extracted. After chaotic mapping based on the initial value of the four-dimensional chaotic system, the first scrambling sequence X, the second scrambling sequence Y, the third scrambling sequence Z, and the fourth scrambling sequence L are recovered. The data at the receiving end is decoded and recovered based on the first scrambling sequence X, the second scrambling sequence Y, the third scrambling sequence Z, and the fourth scrambling sequence L.

7. A chaotic polarization coding receiver based on grouped multicarrier modulation, characterized in that, include: The decoding module is used to demodulate the transmitted information sent in claim 4 using orthogonal frequency division multiplexing technology, and to separate the key from the transmitted information to recover the signal; The demodulation and separation module is used to sequentially perform QPSK demodulation and freeze bit separation operations on the decoded and recovered signal to obtain the original data.

8. A chaotic polar coding method based on grouped multicarrier modulation, characterized in that, include: At the transmitting end, the original data is divided into blocks and then polar-coded to obtain encoded data. During the encoding process, the reliability of each bit position is determined according to the channel characteristics. The most reliable bits are selected to place information bits, and the other positions are set as frozen bits. The encoded data is QPSK modulated to obtain a modulated signal. A perturbation factor is generated through a four-dimensional chaotic system to encrypt the freeze matrix and the modulated signal, resulting in an encrypted signal. The freeze matrix contains the position information of the frozen bits after polarization coding. The initial value of the obtained four-dimensional chaotic system is mixed with the encrypted signal to obtain transmission information, which is then transmitted using orthogonal frequency division multiplexing technology. At the receiving end, the transmitted information is demodulated using orthogonal frequency division multiplexing (OFDM) technology, the key is separated from the transmitted information to recover the signal, and then the original data is obtained after sequentially undergoing QPSK demodulation and separation of frozen bits. The process of generating a perturbation factor through a four-dimensional chaotic system to encrypt the frozen matrix and the modulated signal to obtain an encrypted signal includes: Four sets of chaotic sequences (x) were generated using a four-dimensional hyperchaotic model. n , y n , z n , l n The four-dimensional hyperchaotic model is represented as: ； In the formula, X, Y, Z, and L are state variables, and a, b, c, d, and e are parameters of the four-dimensional hyperchaotic model. , , , The derivatives of X, Y, Z, and L; Through chaotic sequence (x) n , y n , z n , l n The perturbation factor is generated, and the frozen matrix, the modulated signal constellation, the frozen bits, and the subcarriers are encrypted to obtain the encrypted signal. The encryption rules are as follows: ； In the formula, mod() is the modulo function; sort() sorts the array matrix in ascending order and returns the sorted array; T is the transpose matrix; X n The first scrambling sequence is used as an angle perturbation factor for constellation rotation to perturb the entire signal; Y n Z is the second scrambling sequence, used as a perturbation factor for the frozen matrix. n This is the third scrambling sequence, used as a perturbation factor for the fill bits on the frozen bits; L n This is the fourth scrambling sequence, used as a perturbation factor for the subcarrier position.

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