阅读说明：本技术 一种基于5g网络的非对称椭圆曲线加密的安全通信系统 (5G network-based security communication system for asymmetric elliptic curve encryption ) 是由 李齐良 白皓若 肖涛 胡淼 唐向宏 曾然 于 2021-06-28 设计创作，主要内容包括：本发明基于5G网络的非对称椭圆曲线加密的安全通信系统：发送端包括j路结构：信号发生器连接映射器,映射器连接两椭圆曲线加密器,两加密器之间连接公钥接收器,加密器通过乘法器连接加法器,加法器连接串并变换器；串并变换器N个端口连接IFFT,IFFT j×N个端口连接并串变换器,并串变换器依次通过循环前缀导入器、数模变换器、滤波器、上变频器连接5G发射天线,将信号发出；接收端的5G接收天线依次通过下变频器、滤波器、模数变换器、去导频循环前缀器连接串并变换器,串并变换器j×N个输出端口连接FFT,FFT连接j路结构：FFTN个端口连接并串变换器,并串变换器连接两乘法器,乘法器依次通过积分器、解密器连接映射器,两解密器间连接公钥私钥发生器。(The invention relates to a 5G network-based asymmetric elliptic curve encrypted secure communication system, which comprises the following steps: the sending end comprises a j path structure: the signal generator is connected with the mapper, the mapper is connected with the two elliptic curve encryptors, the public key receiver is connected between the two encryptors, the encryptors are connected with the adder through the multiplier, and the adder is connected with the serial-parallel converter; n ports of the serial-parallel converter are connected with IFFT, the IFFT j multiplied by N ports are connected with the parallel-serial converter, the parallel-serial converter is connected with a 5G transmitting antenna through a cyclic prefix importer, a digital-to-analog converter, a filter and an up-converter in sequence, and signals are sent out; the 5G receiving antenna of the receiving end is connected with the serial-parallel converter through the down converter, the filter, the analog-to-digital converter and the pilot frequency removing cyclic prefix device in sequence, j multiplied by N output ports of the serial-parallel converter are connected with FFT, and the FFT is connected with a j-path structure: FFTN ports are connected with a parallel-serial converter, the parallel-serial converter is connected with two multipliers, the multipliers are connected with a mapper through an integrator and a decryptor in sequence, and a public key and private key generator is connected between the two decryptors.)

1. A secure communication system based on asymmetric elliptic curve encryption of 5G network is characterized in that,

the method comprises the following steps:

the sending end comprises j paths of structures, and each path of structure is as follows: the signal generator is connected with a first mapper, the first mapper is connected with two elliptic curve encryptors, an elliptic curve public key receiver is connected between the two elliptic curve encryptors, each elliptic curve encryptor is connected with an adder after passing through a first multiplier, the adder is connected with a first series-parallel converter, the first series-parallel converter is connected to an IFFT converter through N ports, j multiplied by N output ports of the IFFT converter are connected with the first parallel-serial converter, the first parallel-serial converter is connected with a 5G transmitting antenna after passing through a cyclic prefix lead-in device, a digital-analog converter, a first filter and an up-converter in sequence, and the 5G transmitting antenna transmits signals;

a 5G receiving antenna of a receiving end receives signals; the 5G receiving antenna is connected with the second serial-parallel converter through the down converter, the second filter, the analog-to-digital converter and the pilot-frequency-removing cyclic prefix device in sequence, j multiplied by N output ports of the second serial-parallel converter are connected with the FFT converter, the FFT converter is connected with j paths of structures, and each path of structure is as follows: n ports of the FFT converter are connected to a second parallel-serial converter, the second parallel-serial converter is connected with two second multipliers, the two multipliers are respectively connected with a second mapper after passing through an integrator and a decryptor in sequence, and an elliptic curve public key and private key generator is connected between the two decryptors.

2. The asymmetric elliptic curve encryption secure communication system based on 5G network as claimed in claim 1, wherein the public key private key generator utilizes an ellipse Y²＝X³+X²+1(modp) generates a finite field, a private key is given, and a public key is generated through point addition, subtraction, multiplication and division operation of the finite field of the elliptic curve; the receiving end generates a public key in a limited domain through a corresponding algorithm and sends the public key to the sending end, the sending end encrypts information by using the public key, the receiving end decrypts the information by using a private key, and p is a prime number.

3. The asymmetric elliptic curve encryption secure communication system based on 5G network as claimed in claim 2, wherein at the transmitting end, the j-path signal generator generates the information sequence mj and transmits it to the corresponding mapper, and according to the gray code mapping rule, the bits are mapped into x combinations_j,y_jTwo symbol data.

4. The asymmetric elliptic curve encryption secure communication system based on 5G network as claimed in claim 3, wherein at the transmitting end, the public key received by the j-way public key receiver is respectively applied to the symbol x by two elliptic curve encryptors_j,y_jEncrypted to obtain an encrypted new symbol x'_j,y′_jTo effect encryption of the information.

5. The secure communication system of claim 4, wherein at the transmitting end, the symbol x 'is output'_j,y′_jThe edge division is multiplied by cos ω t and-sin ω t, and then added by an adder,generating complex symbols x'_j+iy′_jThe encrypted quadrature amplitude modulation is completed, and then the pilot training sequence is added, so that the transmitting end converts the transmitted digital signal into the mapping of the subcarrier amplitude.

6. The asymmetric elliptic curve encryption secure communication system based on 5G network as claimed in claim 5, wherein at the transmitting end, the formed complex symbol sequence is converted into a parallel symbol stream by a first serial-to-parallel converter; utilizing an IFFT converter to perform inverse fast Fourier transform, and converting the symbols of the frequency domain to the time domain; every N serial-to-parallel converted symbols are modulated by a different subcarrier.

7. The 5G network-based asymmetric elliptic curve encryption secure communication system according to claim 6, wherein at the transmitting end, the time domain symbol output by the IFFT converter is converted into a serial signal by the first parallel-to-serial converter, and the signal is transmitted through the cyclic prefix importer, the digital-to-analog converter, the first filter, the up-converter and the 5G transmitting antenna.

8. The asymmetric elliptic curve encryption security communication system based on 5G network as claimed in any one of claims 4-7, wherein at the receiving end, after the 5G receiving antenna receives the signal, the signal passes through down converter, second filter, A/D converter, and de-pilot cyclic prefix device in sequence, and then the serial symbols are converted into parallel symbols by the second serial-to-parallel converter.

9. The PON of claim 8, wherein at a receiving end, the frequency domain symbols output by the FFT converter are converted into j serial symbols through j second parallel-to-serial converters, each serial symbol has N symbols, each serial symbol is divided into two paths, each symbol is multiplied by cos ω t and-sin ω t, and the integration is performed in one period by a corresponding integrator, and the jth path is x 'to obtain x'_j,y′_jAnd then subtracts the pilot training sequence.

10. The system of claim 9, wherein the receiving end performs an operation in a decryptor using a private key generated by an elliptic curve public-private key generator to convert the symbol x'_j,y′_jDecrypting to obtain x_j,y_jX is mapped by a second mapper_j,y_jThe corresponding original information mj is restored.

Technical Field

The invention belongs to the technical field of secret communication and information security in a 5G network, and particularly relates to a 5G network-based asymmetric elliptic curve encrypted secure communication system.

Background

The 5G is a 5 th generation mobile communication technology, which makes full use of frequency band resources, and the Orthogonal Frequency Division Multiplexing (OFDM) used therein is a technology that uses mutually orthogonal multiple subcarriers, and first performs quadrature amplitude modulation (M-QAM) or phase shift keying (M-PSK) modulation on information, then modulates the information onto each subcarrier, maps the signal into complex symbols, converts the signal into a time domain signal using Inverse Fast Fourier Transform (IFFT), adds a pilot frequency and a cyclic prefix, and transmits the signal using a 5G antenna by digital-to-analog conversion and up-conversion. At the receiving end, the received information is converted into frequency domain information by down-conversion, pilot frequency and cyclic prefix are removed, the received information is converted into frequency domain information by Fast Fourier Transform (FFT), and then the original information is demodulated by coherent demodulation and mapping relation. However, in the prior art, the communication security problem still exists.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a secure communication system based on asymmetric elliptic curve encryption of a 5G network. The invention has the innovation points that a public key is generated by utilizing an elliptic curve algorithm, a symbol generated by QAM modulation is asymmetrically encrypted, a signal is modulated onto each subcarrier by utilizing Inverse Fast Fourier Transform (IFFT) and is superposed into a time domain signal, and the time domain signal is transmitted out through a 5G transmitting antenna by introducing a prefix, performing digital-to-analog conversion, filtering and performing up-conversion. Thus, an attacker cannot directly recover information without the private key. At a receiving end, down-conversion, filtering, analog-to-digital conversion and cyclic prefix removal are carried out, received information is converted into frequency domain information by using Fast Fourier Transform (FFT), then coherent demodulation is carried out to recover encrypted symbols, then symbols generated by QAM modulation are recovered by using a private key in an elliptic curve algorithm, and transmitted information is demodulated through a mapping relation.

In order to achieve the purpose of the invention, the invention adopts the following technical scheme:

a secure communication system based on asymmetric elliptic curve cryptography of a 5G network, comprising:

the sending end comprises j paths of structures, and each path of structure is as follows: the signal generator is connected with a first mapper, the first mapper is connected with two elliptic curve encryptors, an elliptic curve public key receiver is connected between the two elliptic curve encryptors, each elliptic curve encryptor is connected with an adder after passing through a first multiplier, the adder is connected with a first series-parallel converter, the first series-parallel converter is connected to an IFFT converter through N ports, j multiplied by N output ports of the IFFT converter are connected with the first parallel-serial converter, the first parallel-serial converter is connected with a 5G transmitting antenna after passing through a cyclic prefix lead-in device, a digital-analog converter, a first filter and an up-converter in sequence, and the 5G transmitting antenna transmits signals;

a 5G receiving antenna of a receiving end receives signals; the 5G receiving antenna is connected with the second serial-parallel converter through the down converter, the second filter, the analog-to-digital converter and the pilot-frequency-removing cyclic prefix device in sequence, j multiplied by N output ports of the second serial-parallel converter are connected with the FFT converter, the FFT converter is connected with j paths of structures, and each path of structure is as follows: n ports of the FFT converter are connected to a second parallel-serial converter, the second parallel-serial converter is connected with two second multipliers, the two multipliers are respectively connected with a second mapper after passing through an integrator and a decryptor in sequence, and an elliptic curve public key and private key generator is connected between the two decryptors.

As an optimal scheme, a public key and a private key generated by a public key and private key generator are generated by corresponding elliptic curves in a limited domain through corresponding algorithms, a receiving end sends the public key to a sending end, the sending end encrypts information by using the public key, and the receiving end decrypts the information by using the private key.

As the preferred scheme, at the transmitting end, a j-path signal generator generates an information sequence mj and transmits the information sequence mj to a corresponding mapper, and various bit combinations are mapped into x according to the mapping rule of Gray codes_j,y_jTwo symbol data.

Preferably, at the transmitting end, the public key received by the j-path public key receiver respectively corresponds to the symbol x through two elliptic curve encryptors_j,y_jEncrypted to obtain an encrypted new symbol x'_j,y′_jThus, encryption of information is achieved.

Preferably, at the transmitting end, the output symbol x'_j,y′_jThe divided edges are multiplied by cos ω t and-sin ω t and then added by an adder to generate a complex symbol x'_j+iy′_jThe encrypted Quadrature Amplitude Modulation (QAM) is completed, plus a pilot training sequence. The transmitting end thus converts the transmitted digital signal into a mapping of subcarrier amplitudes.

Preferably, at the transmitting end, the formed complex symbol sequence is converted into a parallel symbol stream by a first serial-to-parallel converter; and performing inverse fast Fourier transform by using an IFFT transformer to transform the symbols of the frequency domain to the time domain. Every N serial-to-parallel converted symbols are modulated by a different subcarrier.

Preferably, at the transmitting end, the time domain symbol output by the IFFT converter is converted into a serial signal by the first parallel-to-serial converter, and the serial signal is transmitted through the cyclic prefix importer, the digital-to-analog converter, the first filter, the upconverter, and the 5G transmitting antenna.

Preferably, at the receiving end, the first 5G receiving antenna receives the signal, and then the signal passes through the first down converter, the second filter, the first analog-to-digital converter, and the first pilot-removal cyclic prefix device in sequence, and then the serial symbol is converted into the parallel symbol by the second serial-to-parallel converter.

Preferably, at the receiving end, FFThe frequency domain symbols output by the T converter are converted into j paths of serial symbols (N symbols in each path) through j second parallel-to-serial converters. Each path of serial symbols is divided into two paths, multiplied by cos ω t and-sin ω t respectively, and integrated in one period by using a corresponding integrator, and the first path obtains x'₁,y′₁(ii) a …, respectively; line j gives x'_j,y′_jAnd then subtracts the pilot training sequence.

Preferably, at the receiving end, the sign x 'is calculated in a decryptor by using a private key generated by an elliptic curve public key private key generator'_j,y′_jDecrypting to obtain x_j,y_j。

Preferably, at the receiving end, x is mapped by the second mapper_j,y_jThe corresponding original information mj is restored.

The invention relates to a safe communication system based on asymmetric elliptic curve encryption of a 5G network, which has the following principles and processes: the public key generator generates a finite field using an elliptic curve. For example: using an ellipse Y²＝X³+X²The +1(modp) (p is prime number) generates a finite field, a private key d is given, a point G on the finite field is given, and a public key Q ═ dG is generated through four arithmetic rules of points of an elliptic curve finite field, which is easy to obtain. Thus, such encryption is secure. The receiving end generates a public key in a limited domain through a corresponding algorithm and sends the public key to the sending end, the sending end encrypts information by using the public key, and the receiving end decrypts by using the private key. At the transmitting end, the 1 st signal generator generates an information sequence m1 to be transmitted to the 1 st mapper, and various bit combinations are mapped into x according to the mapping rule of the Gray code₁,y₁Two symbol data …, the j information generator generates information sequence mj to be transmitted to the j mapper, and various bit combinations are mapped into x according to the mapping rule of Gray code_j,y_jTwo symbol data. The public key received by the 1 st public key receiver is used for respectively encrypting the symbol x by the 1 st and the 2 nd elliptic curve encryptors₁,y₁Encrypting to obtain a new encrypted symbol x'₁,y′₁…, the public key received by the jth public key receiver is used to encrypt the symbol x by the 2j-1 nd and 2j th elliptic curve encryptors respectively_j,y_jEncrypting to obtain a new encrypted symbol x'_j,y′_j. Thus, the encryption of the information is realized. Then the 1 st and 2 nd elliptic curve encryptors output symbols x'₁,y′₁The divided sides are multiplied by cos ω t and-sin ω t and then added by a 1 st adder to generate a complex symbol x'₁+iy′₁Adding pilot training symbol …, the 2j-1 nd and 2j th elliptic curve encryptor outputting symbol x'_j,y′_jThe divided sides are multiplied by cos ω t and-sin ω t and then added by a jth adder to generate a complex symbol x'_j+iy′_jAnd pilot training symbols are added, so that encrypted Quadrature Amplitude Modulation (QAM) and encryption and pilot addition are completed, and a transmitting end converts a transmitted digital signal into mapping of subcarrier amplitude.

Meanwhile, the 1 st adder forms complex symbol sequence, and the 1 st serial-parallel converter converts the serial symbol sequence into parallel symbol stream. The symbol sequence formed by the 2 nd adder is converted into a parallel symbol stream by the 2 nd serial-to-parallel converter …, and the symbol sequence formed by the jth adder is converted into a parallel symbol stream by the jth serial-to-parallel converter. And performing inverse fast Fourier transform by using an IFFT transformer to transform the frequency domain form of the data to the time domain. Every N serial-to-parallel converted symbols are modulated by a different subcarrier. The time domain symbol output by the IFFT converter is converted into a serial signal through a 1 st parallel-serial converter, and information is transmitted out through a cyclic prefix importer, a digital-to-analog converter, a first filter and an up-converter by utilizing a 5G transmitting antenna.

After transmission through a spatial wireless channel, at a receiving end, a wireless signal is received by using a 5G receiving antenna, and after passing through a down converter, a second filter, an analog-to-digital converter (converting an analog signal into a digital symbol) and a cyclic prefix remover (removing a prefix), a serial symbol is converted into a parallel symbol by using a second serial-to-parallel converter. Converting serial symbols to serial symbols using a j +1 th serial-to-parallel converterConverted to parallel symbols. The frequency domain symbols output by the FFT transformer are converted into j paths of serial symbols (N symbols per path) by j parallel-to-serial converters. Each path of serial symbols is divided into two paths, multiplied by cos ω t and-sin ω t respectively, and integrated in one period by using a corresponding integrator, and the first path obtains x'₁,y′₁The training pilot is subtracted. … are provided. Line j gives x'_j,y′_jThe training pilot is subtracted. The private key generated by the 1 st public key and private key generator passes through the 1 st decryptor and the 2 nd decryptor, and the first road symbol x 'is subjected to the algorithm of an elliptic curve finite field'₁,y′₁Decrypting to obtain x₁,y₁…, the private key generated by the jth public-private key generator is processed by the 2j-1 and 2j decryptors by using an algorithm of an elliptic curve finite field to the jth symbol x'_j,y′_jDecrypting to obtain x_j,y_j. The first path passes x through the j +1 th mapper₁,y₁To restore the original information m 1.. j, the jth path passes x through the 2j mapper_j,y_jThe corresponding original information mj is restored.

Compared with the prior art, the invention has the beneficial effects that:

the invention realizes the multi-access wireless security communication of asymmetric elliptic curve encryption in the 5G network, and the security is as follows: the public key generator generates a finite field using an elliptic curve, such as: using an ellipse Y²＝X³+X²The +1(mod p) (p is a prime number) generates a finite field, a private key d is given, a point G on the finite field is given, and a public key Q ═ dG is generated through four arithmetic rules of points of an elliptic curve finite field, which is easy to obtain. Thus, this encryption technique is secure.

Drawings

Fig. 1 is a block diagram of a secure communication system based on asymmetric elliptic curve cryptography in a 5G network according to an embodiment of the present invention.

Fig. 2(a) is a constellation diagram before encryption according to an embodiment of the present invention, and fig. 2(b) is a constellation diagram after encryption according to an embodiment of the present invention. It is shown that the transmitted information cannot be recovered by the encrypted constellation.

Fig. 3 is a constellation diagram recovered by a receiving end after an OFDM encrypted communication system passes through a rayleigh channel according to an embodiment of the present invention.

Fig. 4(a) shows the original signal transmitted in the first path, and fig. 4(b) shows the demodulated signal.

Wherein:

1 st signal generator 1-1, … j signal generator 1-j;

1 st mapper 2-1, …, jth mapper 2-j;

the 1 st encryptor 3-1, the 2 nd encryptor 3-2, … the 2j-1 st encryptor 3- (2j-1), the 2j encryptor 3-2 j;

1 st public key receiver 4-1, …, jth public key receiver 4-j;

a 1 st multiplier 5-1, a 2 nd multiplier 5-2, …, a 2j-1 st multiplier 5- (2j-1), a 2j multiplier 5-2 j;

1 st adders 6-1, …, j th adder 6-j;

a 1 st serial-parallel converter 7-1, a 2 nd serial-parallel converter 7-2, … and a jth serial-parallel converter 7-j;

an IFFT converter 8;

a 1 st parallel-to-serial converter 9-1, a 2 nd parallel-to-serial converter 9-2, …, a j +1 th parallel-to-serial converter 9- (j + 1);

a cyclic prefix importer 10, a digital-to-analog converter 11 and a 1 st filter 12-1;

an up-converter 13;

a 5G transmitting antenna 14;

a 5G receiving antenna 15;

a down converter 16, a 2 nd filter 12-2, an analog-to-digital converter 17 and a pilot frequency removal cyclic prefix device 18;

a j +1 th serial-to-parallel converter 7- (j + 1);

an FFT converter 19;

the 2j +1 th multiplier 5- (2j +1), …, the 4j-1 th multiplier 5- (4j-1) and the 4j multiplier 5-4 j;

1 st integrator 20-1, 2 nd integrators 20-2, …, 2j integrator 20-2 j;

a j +1 th mapper 2- (j +1), a j +2 th mapper 2- (j +2), …, a 2j th mapper 2-2 j;

the 1 st decryptor 21-1, the 2 nd decryptors 21-2, …, the 2j-1 st decryptor 21- (2j-1), the 2j decryptor 21-2 j; 1 st public and private key generator 22-1, 2 nd public and private key generator 22-2, …, j th public and private key generator 22-j.

Detailed Description

In order to more clearly illustrate the embodiments of the present invention, the following description will explain the embodiments of the present invention with reference to the accompanying drawings. It is obvious that the drawings in the following description are only some examples of the invention, and that for a person skilled in the art, other drawings and embodiments can be derived from them without inventive effort.

The embodiment of the invention discloses a 5G network-based asymmetric elliptic curve encrypted secure communication system, which comprises a sending end and a receiving end, wherein the sending end and the receiving end communicate through a wireless channel between sending and receiving antennas.

The transmitting end specifically comprises a 1 st signal generator, an … th signal generator, a 1 st mapper, a … th mapper, a 1 st encryptor, a 2 nd encryptor, a … nd 2j-1 encryptor, a 2j encryptor, a 1 st public key receiver, a … th public key receiver, a j public key receiver, a 1 st multiplier, a 2 nd multiplier, a … th, a 2j-1 st multiplier, a 2j multiplier, a 1 st adder, a j adder, a 1 st serial-parallel converter, a 2 nd serial-parallel converter, …, a j serial-parallel converter, an IFFT converter, a 1 st parallel-serial converter, a 2 nd parallel-serial converter, …, a j +1 th parallel-serial converter, a cyclic prefix importer, a digital-to-analog converter, a first filter, an up-converter and a 5G transmitting antenna.

The receiving end comprises a 5G receiving antenna, a down converter, a second filter, an analog-to-digital converter, a pilot-removing cyclic prefix device, a j +1 serial-to-parallel converter, an FFT converter, a 2j +1 multiplier, …, a 4j-1 multiplier, a 4j multiplier, a 1 st integrator, a 2 nd integrator, …, a 2j integrator, a j +1 th mapper, a j +2 th mapper, …, a 2j mapper, a 1 st decryptor, a 2 nd decryptor, …, a 2j-1 st decryptor and a 2j decryptor.

The receiving end is connected with the transmitting end through wireless channels of two transmitting and receiving antennas.

The public key and the secret key generator generate a finite field by utilizing an elliptic curve, which is as follows: using an ellipse Y²＝X³+X²The public key Q ═ dG is easily obtained by giving a private key d and a point G on the finite field, and by using the elliptic curve finite field point four arithmetic rules, but with the public key Q, it is difficult to obtain the private key d in reverse, and an excessively long arithmetic time is required. Such encryption is therefore secure. The receiving end generates a public key in a limited domain through a corresponding algorithm and sends the public key to the sending end, the sending end encrypts information by using the public key, and the receiving end decrypts by using the private key. At the transmitting end, the 1 st signal generator generates an information sequence m1 to be transmitted to the 1 st mapper, and various bit combinations are mapped into x according to the mapping rule of the Gray code₁,y₁Two symbol data …, the j information generator generates information sequence mj and transmits it to the j mapper to map various bit combinations to x according to the mapping rule of Gray code_j,y_jTwo symbol data. The public key received by the 1 st public key receiver is used for respectively encrypting the symbol x by the 1 st and the 2 nd elliptic curve encryptors₁,y₁Encrypting to obtain a new encrypted symbol x'₁,y′₁…, the public key received by the jth public key receiver is used to encrypt the symbol x by the 2j-1 nd and 2j th elliptic curve encryptors respectively_j,y_jEncrypting to obtain a new encrypted symbol x'_j,y′_j. Thus, the encryption of the information is realized. Then the 1 st and 2 nd elliptic curve encryptors output symbols x'₁,y′₁The divided sides are multiplied by cos ω t and-sin ω t and then added by a 1 st adder to generate a complex symbol x'₁+iy′₁Plus pilot training symbol, …, 2j-1 nd, 2j elliptic curve encryptor output symbol x'_j,y′_jThe divided sides are multiplied by cos ω t and-sin ω t and then added by a jth adder to generate a complex symbol x'_j+iy′_jAdding pilot training symbol to complete encrypted Quadrature Amplitude Modulation (QAM), encryption and pilot adding, and the transmitting end converts the transmitted digital signal into subcarrier amplitudeAnd (4) mapping the degree.

The 1 st adder forms complex symbol sequence, and the 1 st serial-parallel converter converts the serial symbol sequence into parallel symbol stream. The symbol sequence formed by the 2 nd adder is converted into a parallel symbol stream by the 2 nd serial-to-parallel converter …, and the symbol sequence formed by the jth adder is converted into a parallel symbol stream by the jth serial-to-parallel converter. And performing inverse fast Fourier transform by using an IFFT transformer to transform the frequency domain form of the data to the time domain. Every N serial-to-parallel converted symbols are modulated by a different subcarrier. The time domain symbol output by the IFFT converter is converted into a serial signal through a 1 st parallel-serial converter, and information is transmitted out through a cyclic prefix importer, a digital-to-analog converter, a first filter and an up-converter by utilizing a 5G transmitting antenna.

After transmission through a spatial wireless channel, at a receiving end, a wireless signal is received by using a 5G receiving antenna, and after passing through a down converter, a second filter, an analog-to-digital converter (converting an analog signal into a digital symbol) and a cyclic prefix remover (removing a prefix), a serial symbol is converted into a parallel symbol by using a second serial-to-parallel converter. The serial symbols are converted to parallel symbols using a j +1 th serial-to-parallel converter. The frequency domain symbols output by the FFT transformer are converted into j paths of serial symbols (N symbols per path) by j parallel-to-serial converters. Each path of serial symbols is divided into two paths, multiplied by cos ω t and-sin ω t respectively, and integrated in one period by using a corresponding integrator, and the first path obtains x'₁,y′₁The training pilot is subtracted. … are provided. Line j gives x'_j,y′_jThe training pilot is subtracted. The private key generated by the 1 st public key and private key generator passes through the 1 st decryptor and the 2 nd decryptor, and the first road symbol x 'is subjected to the algorithm of an elliptic curve finite field'₁,y′₁Decrypting to obtain x₁,y₁…, the private key generated by the jth public-private key generator is processed by the 2j-1 and 2j decryptors by using an algorithm of an elliptic curve finite field to the jth symbol x'_j,y′_jDecrypting to obtain x_j,y_j. The first path passes x through the j +1 th mapper₁,y₁To restore the original information m 1.. j, the jth path passes x through the 2j mapper_j,y_jThe corresponding original information mj is restored.

The above completes the secure communication of 5G-based elliptic curve asymmetric key encryption and decryption.

As shown in fig. 1, the specific connection relationship of the secure communication system based on asymmetric elliptic curve cryptography of the 5G network in this embodiment is as follows:

the transmitting end comprises a 1 st signal generator 1-1, a.j signal generator 1-j; the 1 st mapper 2-1, · the jth mapper 2-j; a 1 st encryptor 3-1, a 2 nd encryptor 3-2,. a 2j-1 st encryptor 3- (2j-1), a 2j encryptor 3-2 j; a 1 st public key receiver 4-1,. and a jth public key receiver 4-j; a 1 st multiplier 5-1, a 2 nd multiplier 5-2, a.logins, a 2j-1 st multiplier 5- (2j-1), a 2j multiplier 5-2 j; the 1 st adder 6-1 and the jth adder 6-j; a 1 st serial-parallel converter 7-1, a 2 nd serial-parallel converter 7-2,. and a jth serial-parallel converter 7-j; an IFFT converter 8; the 1 st parallel-serial converter 9-1; a cyclic prefix importer 10, a digital-to-analog converter 11, a 1 st filter 12-1 and an up-converter 13; 5G transmit antenna 14.

The right port of the 1 st signal transmitter 1-1 is connected to the left port of the 1 st mapper 2-1, and the right first and second ports of the 1 st mapper 2-1 are connected to the left two ports of the 1 st encryptor 3-1 and the 2 nd encryptor 3-2, respectively. The lower port of the 1 st encryptor 3-1 is connected with the upper port of the 1 st public key receiver 4-1, and the upper port of the 2 nd encryptor 3-2 is connected with the lower port of the 1 st public key receiver 4-1. The right port of the 1 st encryptor 3-1 is connected to the left port of the 1 st multiplier 5-1, the right port of the 2 nd encryptor 3-2 is connected to the left port of the 2 nd multiplier 5-2, the right port of the 1 st multiplier 5-1 is connected to the upper port of the 1 st adder 6-1, and the right port of the 2 nd multiplier 5-2 is connected to the lower port of the 1 st adder 6-1. The right port of the 1 st adder 6-1 is connected with the left port of the 1 st serial-parallel converter 7-1, the right port of the jth signal transmitter 1-j is connected with the left port of the jth mapper 2-j, and the first and second ports on the right side of the jth mapper 2-j are respectively connected with the 2j-1 st encryptor 3- (2j-1) and the two ports on the left side of the 2 j-2 j encryptor 3-2 j. The lower port of the 2j-1 encryption device 3- (2j-1) is connected with the upper port of the j public key receiver 4-j, the upper port of the 2j encryption device 3-2j is connected with the lower port of the j public key receiver 4-j, the right port of the 2j-1 encryption device 3- (2j-1) is connected with the left port of the 2j-1 multiplier 5- (2j-1), the right port of the 2j encryption device 3-2j is connected with the left port of the 2j multiplier 5-2j, the right port of the 2j-1 multiplier 5- (2j-1) is connected with the upper port of the j adder 6-j, and the right port of the 2j multiplier 5-2j is connected with the lower port of the j adder 6-j. The right port of the jth adder 6-j is connected with the left port of the jth serial-parallel converter 7-j. The N parallel symbols are divided by the 1 st serial-to-parallel converter 7-1, and the N ports on the right side of the 1 st serial-to-parallel converter 7-1 are connected to the N ports on the left side of the IFFT transformer 8. .... Is divided into N parallel symbols by a jth serial-parallel converter 7-j, and N ports on the right side of the jth serial-parallel converter 7-j are connected to N ports on the left side of an IFFT converter 8. The number of ports on both the left and right sides of the IFFT transformer 8 is j × N.

The right j × N ports of the IFFT converter 8 are connected to the left j × N ports of the 1 st parallel-to-serial converter 9-1, the 1 st parallel-to-serial converter 9-1 converts the parallel sequence into a serial sequence, the right port of the 1 st parallel-to-serial converter 9-1 is connected to the left port of the cyclic prefix importer 10, the right port of the cyclic prefix importer 10 is connected to the left port of the digital-to-analog converter 11, the left port of the digital-to-analog converter 11 is connected to the left port of the 1 st filter 12-1, the right port of the 1 st filter 12-1 is connected to the left port of the down converter 13, and the right port of the down converter 13 is connected to the 5G transmitting antenna 14.

The signal of the 5G transmitting antenna 14 is transmitted to the 5G receiving antenna 15 of the receiving end through the spatial wireless channel. The receiving end comprises a 5G receiving antenna 15; a down converter 16, a 2 nd filter 12-2, an analog-to-digital converter 17 and a pilot frequency removal cyclic prefix device 18; a j +1 th serial-to-parallel converter 7- (j + 1); an FFT converter 19; a 2 nd parallel-to-serial converter 9-2, ·, a j +1 th parallel-to-serial converter 9- (j + 1); the 2j +1 th multiplier 5- (2j +1), …, the 4j-1 th multiplier 5- (4j-1) and the 4j multiplier 5-4 j; 1 st integrator 20-1, 2 nd integrators 20-2, …, 2j integrator 20-2 j; a j +1 th mapper 2- (j +1), a j +2 th mapper 2- (j +2), …, a 2j th mapper 2-2 j; the 1 st decryptor 21-1, the 2 nd decryptors 21-2, …, the 2j-1 st decryptor 21- (2j-1), the 2j decryptor 21-2 j; 1 st public and private key generator 22-1, 2 nd public and private key generator 22-2, …, j th public and private key generator 22-j.

The 5G receiving antenna 15 is connected with a right port of a down converter 16, a left port of the down converter 16 is connected with a right port of a 2 nd filter 12-2, a left port of the 2 nd filter 12-2 is connected with a right port of an analog-to-digital converter 17, a left port of the analog-to-digital converter 17 is connected with a right port of a pilot-removing cyclic prefix device 18, a left port of the pilot-removing cyclic prefix device 18 is connected with a right port of a j +1 th serial-parallel converter 7- (j +1), the j +1 th serial-parallel converter 7- (j +1) converts serial signals into parallel signals, and a j × N port on the left side of the j +1 th serial-parallel converter 7- (j +1) is connected with a right port of an FFT converter 19.

Left side 1 of FFT converter 19: the N port is connected with the right N port of the 2 nd parallel-serial converter 9-2, the output signal of the left port of the 2 nd parallel-serial converter 9-2 is divided into two paths, and the two paths are respectively connected to the two ports on the right side of the 2j +1 th multiplier 5- (2j +1) and the 2j +2 th multiplier 5- (2j +2), the two ports on the left side of the 2j +1 th multiplier 5- (2j +1) and the 2j +2 th multiplier 2- (2j +2) are respectively connected to the two ports on the right side of the 1 st integrator 20-1 and the 2 nd integrator 20-2, and the two ports on the left side of the 1 st integrator 20-1 and the 2 nd integrator 20-2 are respectively connected to the two ports on the right side of the 1 st decryptor 21-1 and the 2 nd decryptor 21-2. The lower port of the 1 st decryptor 21-1 is connected with the upper port of the 1 st public and private key generator 22-1. The upper port of the 2 nd decryptor 21-2 is connected with the lower port of the 1 st public and private key generator 22-1. The left two ports of the 1 st decryptor 21-1 and the 2 nd decryptor 21-2 are respectively connected to the right two ports of the j +1 th mapper 2- (j +1), and the mapper 2- (j +1) restores the first path information m 1.

…。

Left side (j-1) N of FFT converter 19: the jN port is connected with the right N port of the j +1 th parallel-serial converter 9- (j +1), the output signal of the left port of the j +1 th parallel-serial converter 9- (j +1) is divided into two paths, respectively connected to the two ports at the right side of the 4j-1 th multiplier 5- (4j-1) and the 4j multiplier 5-4j, the 4j-1 multiplier 5- (4j-1) and the 4j multiplier 5-4j have two left ports respectively connected to the 2j-1 integrator 20- (2j-1) and the 2j integrator 20-2j and the 2j-1 integrator 20- (2j-1) and the 2j integrator 20-2j have two left ports respectively connected to the 2j-1 decryptor 21- (2j-1) and the 2j decryptor 21-2 j. The lower port of the 2j-1 st decryptor 21- (2j-1) is connected with the upper port of the j public key and private key generator 22-j. The upper port of the 2 j-th decryptor 21-2j is connected with the lower port of the j-th public and private key generator 22-j. The left two ports of the 2j-1 decryptor 21- (2j-1) and the 2j decryptor 22-2j are respectively connected to the right two ports of the 2j mapper 2-2j, and the mapper 2-2j restores the first path of information mj.

The principle of the secure communication system of the present embodiment will be described below with reference to the above-described system configuration.

In the invention, a receiving end and a transmitting end communicate through wireless channels of two 5G transmitting and receiving antennas. Firstly, a public key and secret key generator generates a finite field by utilizing an elliptic curve, and then generates a public key and a private key, specifically: using an ellipse Y²＝X³+X²+1(mod p) (p is a prime number) generates a finite field, and given a private key, a public key is generated through the operation of point addition, subtraction, multiplication and division of the finite field of an elliptic curve, which is easily obtained, but with the public key, the private key is obtained in return, and the calculation needs tens of thousands of years. Thus, this encryption is very secure. The receiving end generates a public key in a limited domain through a corresponding algorithm and sends the public key to the sending end, the sending end encrypts information by using the public key, and the receiving end decrypts by using the private key. At the transmitting end, the 1 st signal generator generates an information sequence m1 to be transmitted to the 1 st mapper, and various bit combinations are mapped into x according to the mapping rule of the Gray code₁,y₁Two symbol data …, the j information generator generates information sequence mj to be transmitted to the j mapper, and various bit combinations are mapped into x according to the mapping rule of Gray code_j,y_jTwo symbol data. The public key received by the 1 st public key receiver is used for respectively aligning the symbol x by the first elliptic curve encryptor and the second elliptic curve encryptor₁,y₁Encrypting to obtain a new encrypted symbol x'₁,y′₁…, the public key received by the jth public key receiver is used to encrypt the symbol x by the 2j-1 nd and 2j th elliptic curve encryptors respectively_j,y_jThe encryption is carried out by the user,obtaining a new symbol x 'after encryption'_j,y′_j. Thus, the encryption of the information is realized. Then the 1 st and 2 nd elliptic curve encryptors output symbols x'₁,y′₁The divided sides are multiplied by cos ω t and-sin ω t and then added by a 1 st adder to generate a complex symbol x'₁+iy′₁Adding pilot training symbol …, the 2j-1 nd and 2j th elliptic curve encryptor outputting symbol x'_j,y′_jThe divided sides are multiplied by cos ω t and-sin ω t and then added by a jth adder to generate a complex symbol x'_j+iy′_jAnd pilot training symbols are added, so that encrypted Quadrature Amplitude Modulation (QAM) and encryption and pilot addition are completed, and a transmitting end converts a transmitted digital signal into mapping of subcarrier amplitude.

The 1 st adder forms complex symbol sequence, and the 1 st serial-parallel converter converts the serial symbol sequence into parallel symbol stream. The symbol sequence formed by the 2 nd adder is converted into a parallel symbol stream by the 2 nd serial-to-parallel converter …, and the symbol sequence formed by the jth adder is converted into a parallel symbol stream by the jth serial-to-parallel converter. And performing inverse fast Fourier transform by using an IFFT transformer to transform the frequency domain form of the data to the time domain. Every N serial-to-parallel converted symbols are modulated by a different subcarrier. The time domain symbol output by the IFFT converter is converted into a serial signal through a 1 st parallel-serial converter, and information is transmitted out through a cyclic prefix importer, a digital-to-analog converter, a 1 st filter and an up-converter by utilizing a 5G transmitting antenna.

After transmission through a spatial wireless channel, at a receiving end, a 5G receiving antenna is used for receiving a wireless signal, and after the wireless signal passes through a down converter, a 2 nd filter, an analog-to-digital converter (converting an analog signal into a digital symbol) and a cyclic prefix remover (removing a prefix), a 2 nd serial-to-parallel converter is used for converting a serial symbol into a parallel symbol. The serial symbols are converted to parallel symbols using a j +1 th serial-to-parallel converter. The frequency domain symbols output by the FFT transformer are converted into j paths of serial symbols (N symbols per path) by j parallel-to-serial converters. Each path of serial symbols is divided into two pathsMultiplying by cos ω t and-sin ω t respectively, and integrating in a period by using corresponding integrators to obtain x in the first path₁′,y₁' subtract training pilot. … are provided. Line j gives x'_j,y′_jThe training pilot is subtracted. The private key generated by the 1 st public key and private key generator passes through the 1 st decryptor and the 2 nd decryptor, and the algorithm of an elliptic curve finite field is utilized to carry out the operation on the first path of symbol x₁′,y₁' proceed to decrypt to get x₁,y₁…, the private key generated by the jth public-private key generator is processed by the 2j-1 and 2j decryptors by using an algorithm of an elliptic curve finite field to the jth symbol x'_j,y′_jDecrypting to obtain x_j,y_j. The first path passes x through the j +1 th mapper₁,y₁To restore the original information m 1.. j, the jth path passes x through the 2j mapper_j,y_jThe corresponding original information mj is restored.

Here, mainly by means of an ellipse Y²＝X³+X²The +1(mod p) (p is a prime number) generates a finite field, and given a private key d, a point G on the finite field generates a public key Q ═ dG through four arithmetic rules of points of an elliptic curve finite field, which is easy to obtain. Such encryption is very secure. The receiving end generates a public key in a limited domain through a corresponding algorithm and sends the public key to the sending end, the sending end encrypts information by using the public key, and the receiving end decrypts by using the private key.

The symbol sequence is confidential through a correlation algorithm of an elliptic curve. The sending end encrypts by a public key, and the receiving end decrypts by different private keys.

The process of implementing communication is briefly summarized as follows:

1. the sending end generates a public key and a private key, the public key is open to the outside, and the private key is used for decryption.

2. The information is QAM modulated.

3. The symbols generated by QAM modulation are encrypted using a public key.

4. Adding pilot training symbol, using IFFT to make Fourier transform, then making parallel-serial transform, adding cyclic prefix.

5. Digital-to-analog conversion converts digital symbols into analog signals.

6. And performing up-conversion.

7. The signal is transmitted using a transmit antenna.

8. After receiving the signal, the down-conversion is carried out, then the analog-to-digital conversion is carried out, the cyclic prefix is removed, and the Fourier transform is carried out by utilizing FFT after the serial-to-parallel conversion.

9. The FFT data is decrypted using the private key.

10. And QAM demodulation is carried out to obtain a transmission signal.

While the preferred embodiments and principles of this invention have been described in detail, it will be apparent to those skilled in the art that variations may be made in the embodiments based on the teachings of the invention and such variations are considered to be within the scope of the invention.