Secure communication method, system, terminal and storage medium based on constellation encryption

Abstract

The present invention relates to the field of secure communication technology, and discloses a secure communication method, system, terminal and storage medium based on constellation encryption, comprising the following steps: presetting an information sequence, configuring an initial key, dividing both the information sequence and the initial key into multiple groups, using an encryption algorithm to obtain multiple groups of ciphertexts, and encoding each group of ciphertexts; configuring multiple modulation modes and phase angles, randomly assigning values ​​to the modulation modes and phase angles respectively, determining the modulation mode used by the current group of ciphertexts based on the values ​​corresponding to the modulation modes used by the current group of ciphertexts and the previous group of ciphertexts; determining the phase angle used by the current group of ciphertexts based on the values ​​corresponding to the phase angle used by the current group of ciphertexts and the previous group of ciphertexts; modulating each group of ciphertexts according to the modulation mode determined above, and then rotating according to the phase angle determined above, to complete the constellation encryption of all groups of ciphertexts. The present invention can effectively improve the confidentiality and security of information transmission.

Description

Technical Field

[0001] The present invention relates to the field of secure communication technology, and in particular to a secure communication method, system, terminal and storage medium based on constellation encryption. Background Art

[0002] In today's highly developed science and technology, wireless communication has become one of the most active technical factors and research hotspots in information productivity. Wireless communication technology is widely used in civil and military communication systems. However, due to the openness and sharing of wireless media, wireless channels are easily intercepted, eavesdropped or maliciously attacked. Therefore, how to ensure the safe and efficient transmission of information is a problem that must be solved in the communication process. Traditional secure communication methods are based on cryptography, usually implemented in the upper layer of the open system interconnection protocol stack, and are widely used to prevent information leakage to unauthorized users. However, with the development of mobile Internet and the substantial improvement of computing power, these encryption algorithms that are currently considered to be sufficiently secure are facing great challenges. As a supplement to higher-level security, physical layer encryption has become a new research direction for encryption technology. Unlike the upper-layer data encryption method, physical layer security focuses more on the perspective of signal modulation and processing, not cryptography. Some studies have pointed out that even if the eavesdropper has unlimited computing power, physical layer encryption technology can ensure transmission security. Its principle is to improve the communication confidentiality by changing the constellation point position of the modulated signal.

[0003] In recent years, physical layer encryption technology has attracted widespread attention. Unlike physical layer security technology, the security provided by physical layer encryption technology does not depend on the channel. Therefore, physical layer encryption technology has obvious advantages in terms of security in static channel environments. The prior art proposes a physical layer security scheme based on a structured minimum shift keying (MSK) modulator. The legitimate sender and receiver change the structure of the modulator according to a set of random numbers generated by a sequence. The eavesdropper cannot demodulate the received signal without knowing the modulator structure. However, considering the high standardization of modern communication protocols, when the eavesdropper knows the modulator structure and part of the original text, the m sequence used to control the modulator structure can be deciphered by the eavesdropper, and this encryption scheme is only for MSK modulation technology. The prior art also proposes a physical layer encryption technology that uses 16 quadrature amplitude modulation (QAM) constellation mapping diversity. When the constellation mapping of the sender and receiver is not known by the eavesdropper as a key, the eavesdropper has no ability to demodulate the received symbols to obtain valid communication content. However, the security provided by this encryption technology is based on the premise that the eavesdropper has no information about the constellation mapping, so the scheme cannot be applied in highly standardized communication protocols.

[0004] In summary, the encryption methods used in existing communication technologies have defects such as being easily deciphered by eavesdroppers and being difficult to apply in highly standardized communication protocols. Summary of the invention

[0005] The purpose of the present invention is to provide a secure communication method, system, terminal and storage medium based on constellation diagram encryption, which realizes constellation diagram encryption of transmission signals by continuously changing the modulation mode and phase angle, can effectively improve the confidentiality and security of information transmission, and is suitable for current highly standardized communication protocols.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] In a first aspect, the present invention provides a secure communication method based on constellation diagram encryption, comprising the following steps:

[0008] S1. Preset the information sequence, configure the initial key, divide the initial key into N groups of subkeys, and generate the cipher stream corresponding to each group of subkeys;

[0009] S2. Divide the information sequence into N groups of information bit streams, XOR each group of information bit streams with a group of password streams to obtain a group of ciphertexts, and obtain N groups of ciphertexts from the N groups of information bit streams. Encode each group of ciphertexts to obtain N groups of ciphertext codes;

[0010] S3. Configure multiple modulation modes and multiple phase angles, and randomly assign values ​​to each modulation mode and phase angle;

[0011] S4. Determine the modulation mode used by the i-th group of ciphertexts based on the value corresponding to the modulation mode used by the i-th group of ciphertexts and the i-1th group of ciphertexts; determine the phase angle used by the i-th group of ciphertexts based on the value corresponding to the phase angle used by the i-th group of ciphertexts and the i-1th group of ciphertexts; 1≤i≤N;

[0012] S5. The i-th group of ciphertexts is modulated according to the modulation method determined in step S4. After modulation, the ciphertexts are rotated according to the phase angle determined in step S4 to obtain the i-th group of constellation diagrams encrypted ciphertexts;

[0013] S6. Loop through steps S4 to S5 until N sets of constellation diagrams are encrypted;

[0014] S7. The encrypted ciphertext of the N groups of constellation diagrams enters the transmission channel after up-conversion and shaping filtering.

[0015] As a possible implementation manner, the initial key is a chaotic sequence generated by a chaotic map; and / or, a cipher stream corresponding to each group of subkeys is generated based on a Chacha20 encryption algorithm.

[0016] As a possible implementation method, the multiple modulation modes include at least BPSK, QPSK, 8PSK, and 16QAM; the multiple phase angles include at least: 0, π / 8, π / 4, and π / 2.

[0017] As a possible implementation method, the modulation mode used by the i-th group of ciphertexts is determined based on the values ​​corresponding to the i-th group of ciphertext codes and the modulation mode used by the i-1-th group of ciphertexts, specifically:

[0018] f i =[f i-1 +h(s i )]%X,1≤i≤N;

[0019] Among them, f i represents the value corresponding to the modulation method used by the i-th group of ciphertext, f i-1 represents the value corresponding to the modulation mode used by the i-1th group of ciphertext, X represents the total number of modulation modes, %X represents the operation modulo X, h(s i ) represents the i-th group of ciphertext encoding.

[0020] As a possible implementation method, the phase angle used by the i-th group of ciphertext is determined based on the values ​​corresponding to the phase angles used by the i-th group of ciphertext encoding and the i-1-th group of ciphertext, specifically:

[0021] g i =[g i-1 +h(s i )]%Y, 1≤i≤N;

[0022] Among them, g i Indicates the value corresponding to the phase angle used by the i-th group of ciphertext, g i-1 represents the value corresponding to the phase angle used by the i-1th group of ciphertext, Y represents the total number of phase angles, %Y represents the operation of modulo Y, h(s i ) represents the i-th group of ciphertext encoding.

[0023] As a possible implementation method, the ciphertext encoding h(s i ) is the number of 1 bits in the ciphertext of the i-th group, or, the ciphertext code of the i-th group h(s i ) is the decimal value of the i-th group of ciphertext.

[0024] As a possible implementation method, S7 and later also include:

[0025] S8. The receiving end performs phase restoration and demodulation on the encrypted ciphertexts of the N groups of constellation diagrams received in turn to obtain the correct information sequence.

[0026] In a second aspect, the present invention provides a secure communication system based on constellation encryption, comprising:

[0027] A ciphertext generation unit is configured to preset an information sequence, configure an initial key, divide the initial key into N groups of subkeys, generate a cipher stream corresponding to each group of subkeys, divide the information sequence into N groups of information bit streams, and obtain a group of ciphertexts by XORing each group of information bit streams with a group of cipher streams, and obtain N groups of ciphertexts by N groups of information bit streams;

[0028] The modulation mode and phase angle determination unit performs encoding processing on each group of ciphertexts to obtain N groups of ciphertext codes, configures multiple modulation modes and multiple phase angles, randomly assigns values ​​to each modulation mode and phase angle, and determines the modulation mode used by the i-th group of ciphertexts based on the values ​​corresponding to the modulation mode used by the i-th group of ciphertext codes and the i-1-th group of ciphertexts; determines the phase angle used by the i-th group of ciphertexts based on the values ​​corresponding to the phase angle used by the i-th group of ciphertext codes and the i-1-th group of ciphertexts; 1≤i≤N;

[0029] The ciphertext obtaining unit after the constellation diagram encryption modulates the i-th group of ciphertext according to the modulation mode determined by the modulation mode and phase angle determination unit, and after modulation, rotates according to the modulation mode and phase angle determined by the phase angle determination unit to obtain the i-th group of ciphertext encrypted by the constellation diagram, and repeats the above operation until the N-th group of ciphertext encrypted by the constellation diagram is obtained.

[0030] In a third aspect, the present invention provides a terminal, comprising a processor and a communication interface coupled to the processor, wherein the processor is used to run a computer program or instruction to implement the secure communication method based on constellation diagram encryption provided in the first aspect.

[0031] In a fourth aspect, the present invention provides a storage medium storing a program, wherein the program is used to be executed by a processor to execute the secure communication method based on constellation diagram encryption provided in the first aspect.

[0032] Compared with the prior art, the beneficial effects of the present invention are:

[0033] 1. The secure communication method based on constellation encryption provided by the present invention performs constellation encryption by combining modulation with phase rotation after grouping and encrypting the transmission signal, and both the modulation mode and the phase angle can be flexibly selected, which can effectively avoid the risk of information being eavesdropped and identified due to the use of a single modulation.

[0034] 2. The secure communication method based on constellation diagram encryption provided by the present invention requires the encoding of the previous group of ciphertext to determine the modulation mode and phase angle of each group of ciphertext, which greatly improves the security of information transmission and can effectively prevent eavesdroppers from eavesdropping on and intercepting the transmission signal.

[0035] 3. The secure communication method based on constellation encryption provided by the present invention introduces the chacha20 algorithm to group and encrypt the transmission signal before the constellation encryption is performed on the signal, thereby further reducing the risk of the transmission content being identified by the eavesdropping party and improving the confidentiality and security of information transmission.

[0036] 4. The secure communication method based on constellation encryption proposed in the present invention can disrupt the constellation to implement constellation encryption without adding additional hardware equipment, thereby achieving effective protection of the transmission signal and ensuring that the overall performance of the system is not lost, and is suitable for current highly standardized communication protocols. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0038] Figure 1 This is a flow chart of a secure communication method based on constellation diagram encryption in an embodiment of the present invention;

[0039] Figure 2 It is a schematic diagram of a secure communication method based on constellation diagram encryption in an embodiment of the present invention;

[0040] Figure 3 The constellation diagram encryption principle diagram in the embodiment of the present invention;

[0041] Figure 4 Assigning values ​​to the modulation mode and phase angle in the embodiment of the present invention;

[0042] Figure 5 The constellation diagram of the initial signal and the constellation diagram after constellation encryption in the embodiment of the present invention;

[0043] Figure 6 It is a bit error rate curve of the signal received by the eavesdropping prevention party and the legal receiving party after the transmission signal is encrypted by the constellation diagram in the embodiment of the present invention. DETAILED DESCRIPTION

[0044] In order to clearly describe the technical solutions of the embodiments of the present invention, in the embodiments of the present invention, words such as "first" and "second" are used to distinguish the same items or similar items with basically the same functions and effects. For example, the first threshold and the second threshold are only used to distinguish different thresholds, and their order is not limited. Those skilled in the art can understand that words such as "first" and "second" do not limit the quantity and execution order, and words such as "first" and "second" do not necessarily limit them to be different.

[0045] It should be noted that, in the present invention, words such as "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in the present invention should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific way.

[0046] In the present invention, "at least one" means one or more, and "plurality" means two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone, where A and B can be singular or plural. The character " / " generally indicates that the associated objects before and after are in an "or" relationship. The following at least one item (items) or similar expressions thereof refer to any combination of these items, including any combination of single items (items) or plural items (items). For example, at least one item (items) of a, b or c can mean: a, b, c, the combination of a and b, the combination of a and c, the combination of b and c, or the combination of a, b and c, where a, b, c can be single or multiple.

[0047] Since physical layer encryption technology has obvious advantages in terms of security in a static channel environment, it has attracted extensive attention and research in recent years. The present invention proposes a secure communication method, system, terminal and storage medium based on constellation encryption, which realizes constellation encryption of the transmission signal by continuously changing the modulation mode and phase angle, can effectively improve the confidentiality and security of information transmission, and is suitable for the current highly standardized communication protocol.

[0048] In a first aspect, the present invention provides a secure communication method based on constellation encryption, see Figure 1 , including the following steps:

[0049] S1. Preset the information sequence, configure the initial key, divide the initial key into N groups of subkeys, and generate the cipher stream corresponding to each group of subkeys;

[0050] As a possible implementation manner, the initial key is a chaotic sequence generated by a chaotic map; and / or, a cipher stream corresponding to each group of subkeys is generated based on a Chacha20 encryption algorithm.

[0051] S2. Divide the information sequence into N groups of information bit streams, XOR each group of information bit streams with a group of password streams to obtain a group of ciphertexts, and obtain N groups of ciphertexts from the N groups of information bit streams. Encode each group of ciphertexts to obtain N groups of ciphertext codes;

[0052] As a possible implementation method, the ciphertext encoding h(s i) is the number of 1 bits in the ciphertext of the i-th group, or, the ciphertext code of the i-th group h(s i ) is the decimal value of the i-th group of ciphertext.

[0053] The present invention groups the information sequences before encrypting them with a constellation diagram, adopts the Chacha20 encryption algorithm to generate a subkey cipher stream, and encrypts each group of information sequences based on the cipher stream, which can effectively reduce the risk of eavesdropping on the transmitted information.

[0054] S3. Configure multiple modulation modes and multiple phase angles, and randomly assign values ​​to each modulation mode and phase angle;

[0055] As a possible implementation method, multiple modulation modes include at least binary phase shift keying (BPSK), quadrature phase shift keying (QPSK), 8 phase shift keying (8PSK), and 16 quadrature amplitude modulation (16QAM); multiple phase angles include at least: 0, π / 8, π / 4, and π / 2.

[0056] S4. Determine the modulation mode used by the i-th group of ciphertexts based on the value corresponding to the modulation mode used by the i-th group of ciphertexts and the i-1th group of ciphertexts; determine the phase angle used by the i-th group of ciphertexts based on the value corresponding to the phase angle used by the i-th group of ciphertexts and the i-1th group of ciphertexts; 1≤i≤N;

[0057] As a possible implementation method, the modulation mode used by the i-th group of ciphertexts is determined based on the values ​​corresponding to the i-th group of ciphertext codes and the modulation mode used by the i-1-th group of ciphertexts, specifically:

[0058] f i =[f i-1 +h(s i )]%X,1≤i≤N;

[0059] Among them, f i represents the value corresponding to the modulation method used by the i-th group of ciphertext, f i-1 represents the value corresponding to the modulation mode used by the i-1th group of ciphertext, X represents the total number of modulation modes, %X represents the operation modulo X, h(s i ) represents the i-th group of ciphertext encoding.

[0060] As a possible implementation method, the phase angle used by the i-th group of ciphertext is determined based on the values ​​corresponding to the phase angles used by the i-th group of ciphertext encoding and the i-1-th group of ciphertext, specifically:

[0061] g i =[g i-1 +h(s i )]%Y, 1≤i≤N;

[0062] Among them, g i Indicates the value corresponding to the phase angle used by the i-th group of ciphertext, g i-1 represents the value corresponding to the phase angle used by the i-1th group of ciphertext, Y represents the total number of phase angles, %Y represents the operation of modulo Y, h(s i ) represents the i-th group of ciphertext encoding.

[0063] S5. The i-th group of ciphertexts is modulated according to the modulation method determined in step S4. After modulation, the ciphertexts are rotated according to the phase angle determined in step S4 to obtain the i-th group of constellation diagrams encrypted ciphertexts;

[0064] The present invention adopts a constellation encryption method that combines modulation mode and phase angle rotation. There are multiple modulation modes and phase angles, which can be flexibly selected, effectively avoiding the risk of transmission information being easily eavesdropped and identified due to a single modulation mode. In addition, when encrypting the current group of ciphertexts, the present invention relies on the previous group of ciphertext encoding to select the corresponding modulation mode and phase angle, which greatly improves the security of information transmission and can effectively prevent eavesdroppers from eavesdropping and obtaining the transmission signal.

[0065] S6. Loop through steps S4 to S5 until N sets of constellation diagrams are encrypted;

[0066] S7. The encrypted ciphertext of the N groups of constellation diagrams enters the transmission channel after up-conversion and shaping filtering.

[0067] As a possible implementation method, S7 and later also include:

[0068] S8. The receiving end performs phase restoration and demodulation on the encrypted ciphertexts of the N groups of constellation diagrams received in turn to obtain the correct information sequence.

[0069] To facilitate understanding of the technical solution of the present application, further description is given below in conjunction with specific embodiments.

[0070] In this embodiment, a root raised cosine shaping filter is used, and the channel is a Gaussian white noise channel. The specific parameters of the communication system are as follows:

[0071] 1. Carrier frequency: 10MHz;

[0072] 2. Oversampling rate: 4;

[0073] 3.Symbol rate: 1Msps;

[0074] 4. Roll-off coefficient: 0.35.

[0075] Figure 2 The schematic diagram of the present invention is as follows: first, a information sequence s(n) of length l is preset, and a chaotic sequence k(n) is generated as an initial key using a chaotic map. For example, a chaotic sequence is generated using a Logistic chaotic map, and its mapping expression is:

[0076] x n+1 =λx n (1-x n );

[0077] In the formula, λ is the fractal parameter, x n ∈(0,1), in this embodiment, λ is 4, the initial value x0 of the sequence is 0.33, and after the chaotic sequence is generated, it is quantized into a binary sequence.

[0078] Exemplarily, the Chacha20 encryption algorithm is selected, and the key length required for the state matrix of the encryption algorithm is 256 bits. For ease of operation, the initial key is divided into N groups of subkeys in groups of 256 bits each, and the Chacha20 encryption algorithm is used to generate the password stream corresponding to each group of subkeys. The length of each group of password streams is 512 bits, and the total length of the N groups of password streams is the same as the length l of the information sequence s(n).

[0079] The principle of the Chacha20 encryption algorithm is as follows: The initial state matrix of the Chacha20 encryption algorithm is composed of 4 32-bit constants, a 256-bit key, a 32-bit block count counter, and a 96-bit random number nonce. Among them, the 4 constants are 0x61707865, 0x3320646e, 0x79622d32, and 0x6b206574. Then the block function is called to calculate the initial state matrix, and the block function includes two types of round function calculations: "column" and "diagonal". The Chacha20 encryption algorithm has 20 rounds of operations, in which the odd rounds and even rounds perform round function calculations on the "column" and "diagonal" types respectively. After completing 20 rounds of calculations, the initial matrix has become a new 4×4 state matrix. At this time, the new matrix is ​​vector-added to the initial matrix, and the obtained matrix is ​​serialized in the little-endian mode to obtain a 512-bit cipher stream.

[0080] The information sequence s(n) is divided into N groups of information bit streams, each of which has a length of s. For the convenience of calculation, it is assumed that s is a positive integer multiple of 512. Each group of information bit streams is XORed with a corresponding password stream to obtain a group of ciphertexts, and N groups of information bit streams obtain a total of N groups of ciphertexts.

[0081] Each group of ciphertext is encoded, and the encoding method can be to calculate the number of 1 bits in each group of ciphertext, or to calculate the decimal value of each group of ciphertext. This embodiment adopts the first method, and the i-th group of ciphertext is encoded h(s i ) is as follows:

[0082]

[0083] Wherein, j represents the number of bits in the i-th group of ciphertext, and s(j) represents the j-th bit in the i-th group of ciphertext.

[0084] See also Figure 3 , which is a schematic diagram of the constellation encryption principle of the present invention. Multiple modulation modes and multiple phase angles are randomly assigned values, the value assigned to the modulation mode is less than the total number of modulation modes, and the value assigned to the phase angle is less than the total number of phase angles. The corresponding relationship between the modulation mode and the phase angle and the assigned value is shown in Figure 4 , for the i-th group of ciphertext, the following formula is used to determine the modulation method to be used:

[0085] f i =[f i-1 +h(s i )]%X,

[0086] For example, assuming that the modulation mode used by the i-1th group of ciphertexts is QPSK, Figure 4 It can be seen that the value corresponding to QPSK is 1, so f i-1 =1, this embodiment lists 4 modulation modes, so the value of X is 4. Assume h(s i ) is 9, then 1+9=10, 10 modulo 4 is 2, that is, f i =2, by Figure 4 It can be seen that the modulation mode corresponding to 2 is 8PSK, so the i-th group of ciphertext uses 8PSK modulation.

[0087] For the i-th group of ciphertext, the following formula is used to determine the phase angle to be rotated:

[0088] g i =[g i-1 +h(s i )]% Y,

[0089] For example, assuming that the phase angle of the i-1th group of ciphertext rotation is π / 8, Figure 4 It can be seen that the value corresponding to π / 8 is 4, so g i-1 =4, this embodiment lists 4 phase angles, so the value of Y is 4. Similarly, assuming h(s i ) is 9, then 4+9=13, 13 modulo 4 is 1, that is, g i =1, by Figure 4It can be seen that the modulation mode corresponding to 1 is π / 4, so the i-th group of ciphertext is rotated by a phase angle of π / 4.

[0090] After each group of ciphertexts completes modulation and phase rotation, N groups of constellation diagram-encrypted ciphertexts are obtained. The N groups of constellation diagram-encrypted ciphertexts enter the transmission channel after up-conversion and shaping filtering.

[0091] By adopting the secure communication method based on constellation diagram encryption provided by the present invention, the constellation diagram can be disturbed to implement constellation diagram encryption without adding additional hardware equipment, thereby achieving effective protection of the transmission signal, while ensuring that the overall performance of the system is not lost, and is suitable for current highly standardized communication protocols.

[0092] The receiving end performs phase restoration, demodulation and judgment operations on the first group of received signals through the modulation method and phase rotation angle. Each subsequent group of received signals is phase restored, demodulated and judged according to the modulation method and phase rotation angle determined before sending. Finally, all ciphertexts are decrypted to obtain the correct transmission information.

[0093] The secure communication method based on constellation encryption of the present invention is used to encrypt the signal in the environment of this embodiment. Assuming that there is an eavesdropper who eavesdrops on the signal in this embodiment, the encrypted constellation is as follows: Figure 5 As shown in the figure, the obtained constellation diagram is very different from the common modulation constellation diagram, which can effectively prevent eavesdroppers from identifying the modulation method of the signal. By calculating the bit error rate of the received signal, we can get Figure 6 The comparison of the bit error rate curves is shown. By comparison, it can be seen that the eavesdropper cannot decrypt the signal encrypted by the present invention without knowing the specific encryption method, and the bit error rate is maintained at about 0.5, while the normal receiver can receive the signal normally, indicating that the present invention can effectively prevent the illegal receiver from eavesdropping and intercepting.

[0094] In a second aspect, the present invention provides a secure communication system based on constellation encryption, comprising:

[0095] A ciphertext generation unit is configured to preset an information sequence, configure an initial key, divide the initial key into N groups of subkeys, generate a cipher stream corresponding to each group of subkeys, divide the information sequence into N groups of information bit streams, and obtain a group of ciphertexts by XORing each group of information bit streams with a group of cipher streams, and obtain N groups of ciphertexts by N groups of information bit streams;

[0096] The modulation mode and phase angle determination unit encodes each group of ciphertexts to obtain N groups of ciphertext codes, configures multiple modulation modes and multiple phase angles, randomly assigns values ​​to each modulation mode and phase angle, and determines the modulation mode used by the i-th group of ciphertext codes based on the value corresponding to the modulation mode used by the i-th group of ciphertext codes and the i-1-th group of ciphertexts; determines the phase angle used by the i-th group of ciphertexts based on the value corresponding to the phase angle used by the i-th group of ciphertext codes and the i-1-th group of ciphertexts; 1≤i≤N.

[0097] The ciphertext obtaining unit after the constellation diagram encryption modulates the i-th group of ciphertext according to the modulation mode determined by the modulation mode and phase angle determination unit, and after modulation, rotates according to the modulation mode and phase angle determined by the phase angle determination unit to obtain the i-th group of ciphertext encrypted by the constellation diagram, and repeats the above operation until the N-th group of ciphertext encrypted by the constellation diagram is obtained.

[0098] In a third aspect, the present invention provides a terminal, comprising a processor and a communication interface coupled to the processor, wherein the processor is used to run a computer program or instruction to implement the secure communication method based on constellation diagram encryption provided in the first aspect.

[0099] In a fourth aspect, the present invention provides a storage medium storing a program, wherein the program is used to be executed by a processor to execute the secure communication method based on constellation diagram encryption provided in the first aspect.

[0100] Although the present invention is described herein in conjunction with various embodiments, in the process of implementing the claimed invention, those skilled in the art may understand and implement other variations of the disclosed embodiments by viewing the drawings, the disclosure, and the drawings, etc. In the specification, the word "comprising" does not exclude other components or steps, and "one" or "an" does not exclude multiple situations. A single processor or other unit can implement several functions listed in the specification. Certain measures are recorded in different embodiments, but this does not mean that these measures cannot be combined to produce good results.

[0101] Although the present invention has been described in conjunction with specific features and embodiments thereof, it is apparent that various modifications and combinations may be made thereto without departing from the spirit and scope of the present invention. Accordingly, this specification and the accompanying drawings are merely exemplary illustrations of the present invention and are deemed to cover any and all modifications, variations, combinations or equivalents within the scope of the present invention. Obviously, those skilled in the art may make various modifications and variations to the present invention without departing from the spirit and scope of the present invention. Thus, the present invention is intended to include such modifications and variations if they fall within the scope of the present invention and its equivalents.

Claims

1. A secure communication method based on constellation encryption, characterized in that: The steps include: S1. Preset information sequence, configure initial key, divide the initial key into N groups of subkeys, and generate a cipher stream corresponding to each group of subkeys; S2. Divide the information sequence into N groups of information bit streams, XOR each group of information bit streams with a group of password streams to obtain a group of ciphertexts, and obtain N groups of ciphertexts from N groups of information bit streams, and encode each group of ciphertexts to obtain N groups of ciphertext codes; S3. Configure multiple modulation modes and multiple phase angles, and randomly assign values ​​to each modulation mode and phase angle; S4. Determine the modulation mode used by the i-th group of ciphertexts based on the value corresponding to the modulation mode used by the i-th group of ciphertexts and the i-1th group of ciphertexts; determine the phase angle used by the i-th group of ciphertexts based on the value corresponding to the phase angle used by the i-th group of ciphertexts and the i-1th group of ciphertexts; 1≤i≤N; S5. The i-th group of ciphertexts is modulated according to the modulation method determined in step S4. After modulation, the ciphertexts are rotated according to the phase angle determined in step S4 to obtain the i-th group of constellation diagrams encrypted ciphertexts; S6. Loop through steps S4 to S5 until N sets of constellation diagrams are encrypted; S7. The encrypted ciphertexts of the N groups of constellation diagrams enter the transmission channel after up-conversion and shaping filtering.

2. The secure communication method based on constellation encryption according to claim 1, characterized in that: The initial key is a chaotic sequence generated by chaotic mapping; and / or, a cipher stream corresponding to each group of subkeys is generated based on the Chacha20 encryption algorithm.

3. The secure communication method based on constellation encryption according to claim 1, characterized in that: The multiple modulation modes include at least BPSK, QPSK, 8PSK, and 16QAM; The multiple phase angles include at least: 0, π / 8, π / 4, and π / 2.

4. The secure communication method based on constellation encryption according to claim 1, characterized in that: Based on the values ​​corresponding to the ciphertext encoding of the i-th group and the modulation mode used by the i-1-th group of ciphertext, the modulation mode used by the i-th group of ciphertext is determined, specifically: f i =[f i-1 +h(s i )]%X,1≤i≤N; Among them, f i represents the value corresponding to the modulation method used by the i-th group of ciphertext, f i-1 represents the value corresponding to the modulation mode used by the i-1th group of ciphertext, X represents the total number of modulation modes, %X represents the operation modulo X, h(s i ) represents the i-th group of ciphertext encoding.

5. The secure communication method based on constellation encryption according to claim 1, characterized in that: Based on the values ​​corresponding to the phase angles used by the i-th group of ciphertext codes and the i-1-th group of ciphertexts, the phase angle used by the i-th group of ciphertexts is determined, specifically: g i =[g i-1 +h(s i )]%Y,1≤i≤N; Among them, g i Indicates the value corresponding to the phase angle used by the i-th group of ciphertext, g i-1 represents the value corresponding to the phase angle used by the i-1th group of ciphertext, Y represents the total number of phase angles, %Y represents the operation of modulo Y, h(s i ) represents the i-th group of ciphertext encoding.

6. The secure communication method based on constellation encryption according to claim 4 or 5, characterized in that: The ciphertext code of group i h(s i ) is the number of 1 bits in the ciphertext of the i-th group, or, the ciphertext code of the i-th group h(s i ) is the decimal value of the i-th group of ciphertext.

7. The secure communication method based on constellation encryption according to claim 1, characterized in that: The S7 also includes: S8. The receiving end performs phase restoration and demodulation on the encrypted ciphertexts of the N groups of constellation diagrams received in turn to obtain the correct information sequence.

8. A secure communication system based on constellation encryption, characterized in that: include: A ciphertext generation unit is configured to preset an information sequence, configure an initial key, divide the initial key into N groups of subkeys, generate a cipher stream corresponding to each group of subkeys, divide the information sequence into N groups of information bit streams, and obtain a group of ciphertexts by XORing each group of information bit streams with a group of cipher streams, and obtain N groups of ciphertexts by N groups of information bit streams; The modulation mode and phase angle determination unit performs encoding processing on each group of ciphertexts to obtain N groups of ciphertext codes, configures multiple modulation modes and multiple phase angles, randomly assigns values ​​to each modulation mode and phase angle, and determines the modulation mode used by the i-th group of ciphertexts based on the values ​​corresponding to the modulation mode used by the i-th group of ciphertext codes and the i-1-th group of ciphertexts; determines the phase angle used by the i-th group of ciphertexts based on the values ​​corresponding to the phase angle used by the i-th group of ciphertext codes and the i-1-th group of ciphertexts; 1≤i≤N; The constellation diagram encrypted ciphertext acquisition unit modulates the i-th group of ciphertext according to the modulation mode determined by the modulation mode and phase angle determination unit, and after modulation, rotates according to the modulation mode and phase angle determined by the phase angle determination unit to obtain the i-th group of constellation diagram encrypted ciphertext, and repeats the above operation until N groups of constellation diagram encrypted ciphertext are obtained. The N groups of constellation diagram encrypted ciphertext enter the transmission channel after up-conversion and shaping filtering.

9. A terminal comprising a processor and a communication interface coupled to the processor, wherein the processor is used to run a computer program or instruction to implement the secure communication method based on constellation diagram encryption as described in any one of claims 1 to 7.

10. A storage medium, characterized in that: The storage medium stores a program, and the program is used to be run by a processor to execute the secure communication method based on constellation diagram encryption as described in any one of claims 1 to 7.

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