CN115085819A - A kind of information transmission method and system of natural electromagnetic pulse vector signal energy spectrum - Google Patents

Abstract

The invention discloses an information transmission method and system of a natural electromagnetic pulse vector signal energy spectrum, which relate to the technical field of vector signal transmission, and comprise the following steps: the laser emits a plurality of laser beams to the multi-carrier signal generator, the multi-carrier signal generator emits light multi-carriers, the light multi-carriers are decomposed into multiple paths by using the demultiplexer, and then the light wave of one of the orthogonal polarized waves is transmitted to the double-parallel Mach-Zehnder modulator; two vector signals are modulated on a double parallel Mach-Zehnder modulator by matching with light waves of internal orthogonal polarized waves; then, multiplexing is carried out by using a multiplexer to obtain a normalized lightwave signal; transmitting the data to a digital watermark encryption unit by using a single mode fiber, and embedding a digital watermark; and finally, the receiving end outputs the originally transmitted first vector signal and second vector signal according to the received encrypted light wave signal to finish the transmission of the vector signal. The invention relates to an information transmission method and system of a natural electromagnetic pulse vector signal energy spectrum, which has good transmission effect and high safety performance.

Description

A kind of information transmission method and system of natural electromagnetic pulse vector signal energy spectrum

technical field

The invention relates to the technical field of vector signal transmission, in particular to a method and system for information transmission of a natural electromagnetic pulse vector signal energy spectrum.

Background technique

Vector signal refers to the quadrature modulation in digital modulation to generate IQ two-way signals. A certain point on the coordinate can be determined on the coordinate graph, which is called the reference point. When receiving, the reference point deviates from a series of deteriorations such as channel interference. The position of the source reference point is known as the measurement point. In order to measure the quality of the signal, that is, the gap between the measurement signal and the reference signal, the EVM (Vector Magnitude Error) is quoted, that is, the vector distance between the measurement point and the reference point and the reference point. The ratio of the amplitudes, so the reference point and the measurement point can be regarded as a vector, so the I/Q data is called a vector signal. The so-called vector signal is a signal in which two or more sine wave signals with the same frequency and different phases are superimposed together. The phases of different signals are used to represent different information, so the desired information can be obtained by measuring the phase difference between the signals. Therefore, in the process of vector signal transmission, an information transmission method and system involving the energy spectrum of the vector signal are required.

However, in the existing vector signal energy spectrum information transmission methods and systems, the vector signal is often sent directly from the vector signal transmitter to the oscilloscope. Since the oscilloscope has both the function of vector signal analysis, the error vector amplitude, phase error, etc. of the vector signal are analyzed. The vector signal parameters are tested and displayed. In the traditional vector signal transmission process, the phase difference between the vector signals cannot be displayed clearly, and the information carried by the vector signal is easily intercepted by extracting the phase difference, which makes the safety performance of the vector signal transmission process. poor, resulting in the leakage of vector signal information, so it is necessary to propose a new solution.

The existing vector signal energy spectrum information transmission methods and systems have the shortcomings of poor safety performance of vector signal transmission, easy to cause vector signal information leakage, and high requirements for the transmission system in the process of vector signal transmission. Information transmission method and system for electromagnetic pulse vector signal energy spectrum.

SUMMARY OF THE INVENTION

The main purpose of the present invention is to provide a natural electromagnetic pulse vector signal energy spectrum information transmission method and system, which can effectively solve the existing vector signal energy spectrum information transmission methods and systems in the background technology. It is easy to cause the shortcomings of vector signal information leakage, and the problem of high requirements on the transmission system in the process of vector signal transmission.

In order to achieve the above purpose, the technical solution adopted by the present invention is: a method for information transmission of natural electromagnetic pulse vector signal energy spectrum, comprising the following steps:

S1: The laser emits multiple laser beams of different frequencies to the multi-carrier signal generator, the multi-carrier signal generator emits an optical multi-carrier, and the multi-carrier signal generator selects AWG5200 arbitrary waveform generator. Signal generation requirements, with high signal fidelity, can be expanded to up to 32 channels through multi-unit simultaneous combination, suitable for advanced research, electronic testing and radar, complex electromagnetic environment system design and testing;

S2: Use a demultiplexer to decompose the optical multi-carrier into multiple channels, wherein two optical wave signals are directly transmitted to the multiplexer, and the other optical wave signal is transmitted to the polarization beam splitter, and the first polarization beam splitter The light wave is split into two orthogonally polarized waves, and then one of the orthogonally polarized light waves is transmitted to a double-parallel Mach-Zehnder modulator. The Mach-Zehnder modulator divides the input light into two equal paths. The signal enters the two optical branches of the modulator respectively. The materials used in these two optical branches are electro-optical materials, and the refractive index of the two optical branches changes with the magnitude of the externally applied electrical signal. Since the change of the refractive index of the optical branch will lead to the change of the signal phase, when the output ends of the two branch signal modulators are combined together again, the synthesized optical signal will be an interference signal with varying intensity, which is equivalent to converting the electrical signal The change of the light signal is converted into the change of the light signal, and the modulation of the light intensity is realized;

S3: The natural electromagnetic pulse vector signal sending end sends the microwave first vector signal and the microwave second vector signal to the dual-parallel Mach-Zehnder modulator, and cooperates with the internal orthogonal polarization on a dual-parallel Mach-Zehnder modulator the light wave of the wave modulates the first vector signal and the second vector signal;

S4: The signal modulated by the dual parallel Mach-Zehnder modulators and another light wave of the orthogonally polarized wave are transmitted to the second polarization beam splitter for processing and combination, and the processed and combined signal is the same as the two in step S2. The light wave signal is transmitted to the multiplexer for multiplexing, and the normalized light wave signal is obtained. The polarization beam splitter is used to couple two orthogonally polarized lights into one optical fiber or to combine the orthogonal linearly polarized light. The single output is coupled into two fiber outputs respectively, or it can be reversed to couple two orthogonally polarized beams input from the polarization maintaining fiber branch into a single-mode output fiber, which can be used for power combining of pump lasers , to improve the extinction ratio of fiber lasers;

S5: The normalized light wave signal is amplified by an erbium-doped fiber amplifier, and then transmitted to the digital watermark encryption unit by using a single-mode fiber. The cuckoo algorithm finds the best place to embed the digital watermark, inserts the reversible digital watermark through the differential expansion technology, and completes the encryption of the light wave signal. The erbium-doped fiber amplifier is a fiber doped with a small amount of rare earth element erbium (Er) ions in the quartz fiber. , which is the core of the erbium-doped fiber amplifier, which greatly increases the capacity of optical fiber communication and improves the efficiency of data transmission;

S6: The encrypted lightwave signal is again transmitted to the receiving end through the single-mode optical fiber, and the receiving end outputs the originally transmitted first vector signal and the second vector signal according to the received encrypted lightwave signal to complete the vector signal transmission,

A method based on light wave signal modulation and coherent detection of photons to transmit two microwave vector signals, using a Mach-Zehnder modulator in the light wave to modulate two vector signals with the same microwave carrier frequency, and no modulation in the same fiber In this case, when orthogonally polarized light waves are transmitted for coherent detection, the number of optical carriers and modulators carrying vector signals is only half of the original number, which improves the efficiency of vector signal transmission. The use of balanced detection and coherent detection instruments can reduce the noise of vector signal transmission and ensure the high performance of vector signals. Compared with the conventional microwave vector signal transmission method in the optical fiber link, by using a single fiber carrier to transmit two different microwave vector signals with the same microwave carrier frequency, the required optical carrier of the microwave vector signal is greatly reduced. and the number of modulators. In addition, in the proposed coherent detection method, the influence of the noise of the photodetector is thereby reduced.

Preferably, in step S6, the receiving end outputs the first vector signal and the second vector signal after receiving the encrypted light wave. The specific steps are as follows:

S601: Use a second demultiplexer to separate wavelengths of the encrypted light waves to obtain multiple wavelength signals;

S602: One of the wavelengths is transmitted to the third polarization beam splitter to be split into two light waves to be outputted orthogonally polarized waves;

S603: Send one of the light waves of the orthogonal polarized waves to be output to a coherent detector, where the coherent detector is again modulated with a Mach-Zehnder modulator, and after the modulation is completed, the output is transmitted to the coherent detector terminal to complete the output of the first vector signal and the second vector signal.

Preferably, in step S603, the two vector signals to be transmitted are set as I(t) and Q(t) respectively, and the sub-base and main bias of the dual-parallel Mach-Zehnder modulator at the minimum transmission point are introduced into π/21 is used as the modulation condition, under this condition then the optical signal at the output of the dual parallel Mach-Zehnder modulator can be expressed as:

≈

≈

，式子中，输入到所述双平行马赫曾德调制器的幅度为Ex，角度频率为

，所述双平行马赫曾德调制器的半波电压为Vπ，

，两个矢量信号分别在光载波上的调制，E_y是未调制光载波光场的振幅，

，通过所述单模光纤传输的两个正交极化光波，两个光波发送到相干检测器上，本实施例中，线性偏振光波被分成两个正交极化光波，一个被调制的两个微波矢量信号和其他的无调制，但在同一根光纤中传输调制光波，在接收器处，这两个光波的正交偏振态被分离并传送到一个相干检测器，这里两个微波矢量信号被分离和解调。

, where the amplitude input to the dual parallel Mach-Zehnder modulator is Ex, and the angular frequency is

, the half-wave voltage of the dual-parallel Mach-Zehnder modulator is Vπ,

, the modulation of the two vector signals on the optical carrier respectively, E _y is the amplitude of the optical field of the unmodulated optical carrier,

, the two orthogonally polarized light waves transmitted through the single-mode fiber are sent to the coherent detector. In this embodiment, the linearly polarized light waves are divided into two orthogonally polarized light waves, and one modulated two One microwave vector signal and others are unmodulated, but modulated light waves are transmitted in the same fiber. At the receiver, the orthogonal polarization states of the two light waves are separated and sent to a coherent detector, where the two microwave vector signals separated and demodulated.

，类似的另一个所述电探测器设备的输出信号可表示为：

，通过上式最终输出所述第一矢量信号I(t)和所述第二矢量信号Ｑ(t)。Preferably, an optical mixer is provided on the coherent detection, the output terminal is the output terminal of the optical mixer, and the output terminal of the optical mixer generates four output signals, and the four output signals pass through two For the photodetector output, the output signal of one of the photodetector devices can be expressed as:

, similarly the output signal of another said electrical detector device can be expressed as:

, the first vector signal I(t) and the second vector signal Q(t) are finally output through the above formula.

Preferably, in step S5, first use P cuckoos to create an initial population, calculate the cuckoo function values of the solutions given by different cuckoos, and then sort them, and divide the vector signals I(t) and Q(t) to be watermarked. , the specific I(t)∈(p,I ₁ ,I ₂ ,...,In ), where: _p is the primary key of each element of I( _t ), I ₁ ,I ₂ ,...,In are n attributes of I(t), I(t) consists of m tuples r ₁ , r ₂ , ..., r _m , each tuple has one and only one distinct primary key rp and n attributes Columns rI ₁ , rI ₂ , ..., rI _n , then the initial population number represents the number of cuckoos used to find the optimal solution, and then the optimal solution of the cuckoo function is found, and then the watermark to be embedded u=(u ₁ , u ₂ ,...,u _k ),u∈{0,1}, k≤m, according to the watermark preference selection calculated by the optimal solution of the cuckoo function, the watermark insertion position information is obtained. The cuckoo function aims to To minimize the distortion after embedding the watermark, the cuckoo algorithm selects the best position to embed the watermark for each tuple. In this embodiment, the digital watermark is added to the vector signal by using the cuckoo algorithm. The watermark is embedded in the vector signal to effectively prevent the vector signal from being distorted during transmission. By embedding a watermark on the vector signal instead of encrypting the vector signal, it prevents criminals from privately obtaining the transmitted vector signal. At the same time, the corresponding marking information can be embedded in the watermark to further ensure safety of vector signal transmission.

An information transmission system of natural electromagnetic pulse vector signal energy spectrum, the transmission system includes a preprocessing module, an input module, a watermark embedding module and an output module;

In the preprocessing module, a laser and a multi-carrier signal generator are used to generate an optical multi-carrier; then a demultiplexer is used to decompose the optical multi-carrier into multiple optical signals;

The input module includes a double parallel Mach Zehnder modulator, and the two sets of vector signals to be transmitted and one of the light wave signals are simultaneously entered into the double parallel Mach Zehnder modulator for modulation;

The watermark embedding module is mainly used to embed a watermark into the light wave signal modulated by the dual-parallel Mach-Zehnder modulator, and complete encryption;

The output module outputs again through the coherent detector, and in the coherent detector, modulates again through the dual parallel Mach-Zehnder modulators and then outputs the first vector signal and the second vector signal after embedding the watermark.

Preferably, the preprocessing module, the input module, the watermark embedding module and the output module are communicatively connected through a single-mode optical fiber.

Compared with the prior art, the present invention has the following beneficial effects:

In the present invention, two microwave vector signals are transmitted based on the method of light wave signal modulation and coherent detection of photons, and a Mach-Zehnder modulator is used in the light wave to modulate two vector signals with the same microwave carrier frequency, and in the same When the optical fiber is not modulated, the orthogonally polarized light waves are transmitted for coherent detection, and the number of optical carriers and modulators carrying the vector signal is only half of the original number, which improves the efficiency of vector signal transmission. The use of balanced detection and coherent detection instruments can reduce the noise of vector signal transmission and ensure the high performance of vector signals. Compared with the conventional microwave vector signal transmission method in the optical fiber link, by using a single fiber carrier to transmit two different microwave vector signals with the same microwave carrier frequency, the required optical carrier of the microwave vector signal is greatly reduced. and the number of modulators. In addition, in the proposed coherent detection method, the influence of the noise of the photodetector is reduced, the efficiency of vector signal transmission is guaranteed, the performance of vector signal transmission is reduced, the requirements for the transmission system are reduced, and the transmission system to the vector signal is reduced. influences.

In the present invention, the best position for embedding the digital watermark is found based on the cuckoo algorithm, the reversible digital watermark is inserted through the differential expansion technology, the encryption of the light wave signal is completed, and the digital watermark mark is added to the vector signal by using the cuckoo algorithm. The watermark is embedded in the signal, which can effectively prevent the vector signal from being distorted during the transmission process. By embedding a watermark on the vector signal instead of encrypting the vector signal, it prevents criminals from privately obtaining the transmitted vector signal. At the same time, the corresponding mark information can be embedded in the watermark, further The security of vector signal transmission is guaranteed.

Description of drawings

Fig. 1 is a system block diagram of an information transmission method of a natural electromagnetic pulse vector signal energy spectrum of the present invention;

2 is a flow chart of a method for information transmission of a natural electromagnetic pulse vector signal energy spectrum according to the present invention;

3 is a specific flow chart of step S6 in a method for information transmission of a natural electromagnetic pulse vector signal energy spectrum of the present invention;

FIG. 4 is a system block diagram of an information transmission system of a natural electromagnetic pulse vector signal energy spectrum according to the present invention.

Detailed ways

In order to make the technical means, creative features, achievement goals and effects realized by the present invention easy to understand, the present invention will be further described below with reference to the specific embodiments.

In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "outer", "front end", "rear end", "two ends", "one end" and "the other end" The orientation or positional relationship indicated by etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the indicated device or element must have a specific orientation, with a specific orientation. The orientation configuration and operation are therefore not to be construed as limitations of the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed to indicate or imply relative importance.

In the description of the present invention, it should be noted that, unless otherwise expressly specified and limited, the terms "installed", "provided with", "connected", etc. should be understood in a broad sense, for example, "connected" may be a fixed connection It can also be a detachable connection or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or the internal communication between the two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood in specific situations.

Please refer to Fig. 1-4, the present invention is an information transmission method of natural electromagnetic pulse vector signal energy spectrum, comprising the following steps:

As shown in Figure 1 and Figure 2, S1: The laser emits multiple laser beams of different frequencies to the multi-carrier signal generator, the multi-carrier signal generator emits an optical multi-carrier, and the multi-carrier signal generator uses an AWG5200 arbitrary waveform generator. The AWG5200 Arbitrary Waveform Generator meets demanding signal generation needs with high signal fidelity and can be expanded to up to 32 channels through multi-unit simultaneous combinations for advanced research, electronic test and radar, complex electromagnetic environment system design and testing ;

S2: Use a demultiplexer to decompose the optical multi-carrier into multiple channels, in which two optical wave signals are directly transmitted to the multiplexer, and the other optical wave signal is transmitted to the polarization beam splitter, and is transmitted to the first polarization beam splitter. It is split into two orthogonally polarized light waves, and then one of the orthogonally polarized light waves is transmitted to the double parallel Mach-Zehnder modulator. The Mach-Zehnder modulator divides the input light into two equal signals and enters the modulation respectively. The two optical branches of the device are made of electro-optical materials, and their refractive index changes with the magnitude of the externally applied electrical signal. Since the change of the refractive index of the optical branch will lead to the change of the signal phase, when the output ends of the two branch signal modulators are combined together again, the synthesized optical signal will be an interference signal with varying intensity, which is equivalent to converting the electrical signal The change of the light signal is converted into the change of the light signal, and the modulation of the light intensity is realized;

S3: The natural electromagnetic pulse vector signal sending end sends the microwave first vector signal and the microwave second vector signal to the dual-parallel Mach-Zehnder modulator. the light wave modulates the first vector signal and the second vector signal;

S4: The signal modulated by the dual-parallel Mach-Zehnder modulator and the light wave of another orthogonal polarized wave are transmitted to the second polarization beam splitter for processing and combination, and the combined signal is processed and transmitted with the two-way light wave signal in step S2 Multiplexing to a multiplexer to obtain a normalized lightwave signal, a polarization beam splitter is used to couple two orthogonally polarized lights into one fiber or a single output containing orthogonally linearly polarized light to separately In the two fiber outputs, the two orthogonally polarized beams input from the polarization-maintaining fiber branch can also be coupled into a single-mode output fiber, which can be used to combine the power of the pump laser and improve the extinction of the fiber laser. Compare;

S5: The normalized light wave signal is amplified by an erbium-doped fiber amplifier, and then transmitted to the digital watermark encryption unit using a single-mode fiber. The digital watermark encryption unit reorders the database through a hash function to deal with the reorganization attack, and finds it based on the cuckoo algorithm. The best place to embed the digital watermark is to insert the reversible digital watermark through the differential expansion technology to complete the encryption of the light wave signal. The erbium-doped fiber amplifier is a fiber doped with a small amount of rare earth element erbium (Er) ions in the silica fiber. The core of the erbium fiber amplifier greatly increases the capacity of optical fiber communication and improves the efficiency of data transmission;

S6: The encrypted lightwave signal is again transmitted to the receiving end through the single-mode optical fiber, and the receiving end outputs the originally transmitted first vector signal and the second vector signal according to the received encrypted lightwave signal to complete the vector signal transmission.

A method based on light wave signal modulation and coherent detection of photons to transmit two microwave vector signals, using a Mach-Zehnder modulator in the light wave to modulate two vector signals with the same microwave carrier frequency, and no modulation in the same fiber In this case, when orthogonally polarized light waves are transmitted for coherent detection, the number of optical carriers and modulators carrying vector signals is only half of the original number, which improves the efficiency of vector signal transmission. The use of balanced detection and coherent detection instruments can reduce the noise of vector signal transmission and ensure the high performance of vector signals. Compared with the conventional microwave vector signal transmission method in the optical fiber link, by using a single fiber carrier to transmit two different microwave vector signals with the same microwave carrier frequency, the required optical carrier of the microwave vector signal is greatly reduced. and the number of modulators. In addition, in the proposed coherent detection method, the influence of the noise of the photodetector is thereby reduced.

Wherein, as shown in FIG. 3, in step S6, the receiving end outputs the first vector signal and the second vector signal after receiving the encrypted light wave. The specific steps are as follows:

S601: Use a second demultiplexer to separate wavelengths of the encrypted light waves to obtain multiple wavelength signals;

S602: One of the wavelengths is transmitted to the third polarization beam splitter to be split into two light waves to be outputted orthogonally polarized waves;

S603: Send one of the light waves of the orthogonal polarized waves to be output to a coherent detector, and use the Mach-Zehnder modulator to modulate the coherent detector again. After the modulation is completed, it is transmitted to the output end of the coherent detector to complete the output. the first vector signal and the second vector signal.

Wherein, in step S603, the two vector signals to be transmitted are set as I(t) and Q(t) respectively, and the sub-base and main bias of the dual-parallel Mach-Zehnder modulator at the minimum transmission point are introduced into π/21 As a modulation condition, the optical signal at the output of the dual-parallel Mach-Zehnder modulator can then be expressed as:

，式子中，输入到双平行马赫曾德调制器的幅度为Ex，角度频率为

，双平行马赫曾德调制器的半波电压为Vπ，

，两个矢量信号分别在光载波上的调制，E_y是未调制光载波光场的振幅，

，通过单模光纤传输的两个正交极化光波，两个光波发送到相干检测器上，本实施例中，线性偏振光波被分成两个正交极化光波，一个被调制的两个微波矢量信号和其他的无调制，但在同一根光纤中传输调制光波，在接收器处，这两个光波的正交偏振态被分离并传送到一个相干检测器，这里两个微波矢量信号被分离和解调。≈

, where the amplitude input to the dual parallel Mach-Zehnder modulator is Ex, and the angular frequency is

, the half-wave voltage of the dual-parallel Mach-Zehnder modulator is Vπ,

, the modulation of the two vector signals on the optical carrier respectively, E _y is the amplitude of the optical field of the unmodulated optical carrier,

, the two orthogonally polarized light waves transmitted through the single-mode fiber are sent to the coherent detector. In this embodiment, the linearly polarized light waves are divided into two orthogonally polarized light waves, one modulated by two microwave Vector signals and other unmodulated but modulated light waves are transmitted in the same fiber. At the receiver, the orthogonal polarization states of the two light waves are separated and passed to a coherent detector, where the two microwave vector signals are separated and demodulation.

，类似的另一个电探测器设备的输出信号可表示为：

，通过上式最终输出第一矢量信号I(t)和第二矢量信号Ｑ(t)。Among them, an optical mixer is arranged on the coherent detection, and the output terminal is the output terminal of the optical mixer. The output terminal of the optical mixer generates four output signals, and the four output signals are respectively output through two pairs of photodetectors. One of the photoelectric The output signal of the detector device can be expressed as:

, similarly the output signal of another electrical detector device can be expressed as:

, the first vector signal I(t) and the second vector signal Q(t) are finally output through the above formula.

Among them, in step S5, first use P cuckoos to create an initial population, calculate the cuckoo function value of the solutions given by different cuckoos, and then sort them, and set the vector signals I(t) and Q(t) to be embedded in the watermark, Specific I(t)∈(p,I ₁ ,I ₂ ,...,In ), where: _p is the primary key of each element of I( _t ), I ₁ ,I ₂ ,...,In is I (t) n attributes, I(t) consists of m tuples r ₁ , r ₂ , ..., r _m , each tuple has one and only one distinct primary key rp and n attribute columns rI ₁ , rI ₂ , ..., rI _n , then the initial population number represents the number of cuckoos used to find the optimal solution, and then the optimal solution of the cuckoo function is found, and then the watermark to be embedded u=(u ₁ ,u ₂ ,...,u _k ),u∈{0,1}, k≤m, according to the watermark preference selection calculated by the optimal solution of the cuckoo function, the watermark insertion position information is obtained. The cuckoo function is designed to embed the watermark. After the distortion is reduced to the minimum value, the cuckoo algorithm selects the best position to embed the watermark for each tuple. In this embodiment, the digital watermark is added to the vector signal by using the cuckoo algorithm, and the watermark is embedded in the vector signal. , which can effectively prevent the vector signal from being distorted during the transmission process. Instead of encrypting the vector signal by embedding a watermark on the vector signal, it prevents criminals from privately obtaining the transmitted vector signal. At the same time, the corresponding label information can be embedded in the watermark, which further ensures the vector signal. Transmission security.

As shown in Figure 4, an information transmission system of natural electromagnetic pulse vector signal energy spectrum, the transmission system includes a preprocessing module, an input module, a watermark embedding module and an output module;

In the preprocessing module, a laser and a multi-carrier signal generator are used to generate an optical multi-carrier; then the demultiplexer is used to decompose the optical multi-carrier into multiple optical signals;

The input module includes dual parallel Mach Zehnder modulators, and the two sets of vector signals to be transmitted and one of the light wave signals are simultaneously entered into the dual parallel Mach Zehnder modulators for modulation;

The watermark embedding module is mainly used to embed the watermark into the light wave signal modulated by the dual-parallel Mach-Zehnder modulator, and complete the encryption;

The output module outputs again through the coherent detector, modulates through the double parallel Mach-Zehnder modulator again in the coherent detector, and then outputs the first vector signal and the second vector signal after embedding the watermark.

Among them, the preprocessing module, the input module, the watermark embedding module and the output module are communicated and connected through a single-mode optical fiber.

The basic principles and main features of the present invention and the advantages of the present invention have been shown and described above. Those skilled in the art should understand that the present invention is not limited by the above-mentioned embodiments, and the descriptions in the above-mentioned embodiments and the description are only to illustrate the principle of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have Various changes and modifications fall within the scope of the claimed invention. The claimed scope of the present invention is defined by the appended claims and their equivalents.

Claims (8)

1. A method for transmitting information of a natural electromagnetic pulse vector signal energy spectrum is characterized by comprising the following steps: the method comprises the following steps:

s1: the laser emits a plurality of laser beams with different frequencies to the multi-carrier signal generator, and the multi-carrier signal generator emits one optical multi-carrier;

s2: the optical multi-carrier is decomposed into multiple paths by using a demultiplexer, wherein two paths of optical wave signals are directly transmitted to the multiplexer, the other path of optical wave signals are transmitted to a polarization beam splitter and split into two optical waves of orthogonal polarization waves in a first polarization beam splitter, and then one optical wave of the orthogonal polarization waves is transmitted to a double parallel Mach-Zehnder modulator;

s3: a natural electromagnetic pulse vector signal sending end sends a microwave first vector signal and a microwave second vector signal to the double-parallel Mach-Zehnder modulators, and the first vector signal and the second vector signal are modulated on one double-parallel Mach-Zehnder modulator by matching with light waves of internal orthogonal polarized waves;

s4: the signal modulated by the double parallel Mach-Zehnder modulator and the optical wave of the other orthogonal polarized wave are transmitted to a second polarization beam splitter for processing and combination, and the processed and combined signal and the two paths of optical wave signals in the step S2 are transmitted to a multiplexer for multiplexing to obtain a normalized optical wave signal;

s5: the normalized light wave signal is subjected to signal amplification through an erbium-doped fiber amplifier, and then is transmitted to a digital watermark encryption unit by using a single mode fiber, the digital watermark encryption unit reorders the database through a hash function to cope with recombination attack, the optimal position where the digital watermark is embedded is found based on a cuckoo algorithm, and reversible digital watermark is inserted through a difference expansion technology to complete light wave signal encryption;

s6: and the encrypted light wave signal is transmitted to a receiving end through the single-mode optical fiber again, and the receiving end outputs the originally transmitted first vector signal and the originally transmitted second vector signal according to the received encrypted light wave signal to finish vector signal transmission.

2. The method for transmitting information of natural electromagnetic pulse vector signal energy spectrum according to claim 1, characterized in that: in step S6, the steps of receiving the encrypted optical wave and outputting the first vector signal and the second vector signal by the receiving end are as follows:

s601: separating wavelengths of the encrypted light waves by using a second demultiplexer to obtain a plurality of wavelength signals;

s602: one path of wavelength is transmitted to a third polarization beam splitter and is split into two optical waves of orthogonal polarization waves to be output;

s603: and sending one optical wave of orthogonal polarization waves to be output to a coherent detector, modulating the optical wave again by using the Mach-Zehnder modulator in the coherent detector, and transmitting the modulated optical wave to the output end of the coherent detector to finish outputting a first vector signal and a second vector signal.

3. The method for transmitting information of natural electromagnetic pulse vector signal energy spectrum according to claim 2, characterized in that: in step S603, two vector signals to be transmitted are set as i (t) and q (t), respectively, and the dual parallel mach-zehnder modulator is positioned at the maximumThe sub-basis and main bias of the small transmission point introduce pi/21 as a modulation condition under which the optical signal output at the dual parallel mach-zehnder modulator can be expressed as:

≈

in the formula, the amplitude input to the double parallel Mach-Zehnder modulator is Ex, and the angular frequency is

The half-wave voltage of the double parallel Mach-Zehnder modulator is V pi,

modulation of two vector signals on an optical carrier, respectively, E _y Is the amplitude of the optical field of the unmodulated optical carrier,

two orthogonally polarized light waves transmitted through said single mode fiber, both light waves being sent to a coherent detector.

4. The method of claim 3, wherein the method comprises: an optical mixer is arranged on the coherent detection, the output end of the optical mixer is the output end of the optical mixer, the output end of the optical mixer generates four output signals, the four output signals are respectively output through two pairs of photoelectric detectors, and the output signal of one photoelectric detector device can be expressed as:

similarly, the output signal of another of the electrical detector devices may be expressed as:

finally, the first vector signal i (t) and the second vector signal q (t) are output by the above formula.

5. The method for transmitting information of natural electromagnetic pulse vector signal energy spectrum according to claim 1, characterized in that: in step S5, P cuckoos are used to create an initial population, the cuckoo function values of solutions given by different cuckoos are calculated and then sorted, and vector signals I (t) and q (t) to be embedded with a watermark, specifically I (t) e (P, I) e ₁ ,I ₂ ,...,I _n ) Wherein: p is the primary bond of each element I (t) ₁ ,I ₂ ,...,I _n N attributes of I (t), I (t) consisting of m tuples r ₁ ，r ₂ ，…，r _m Each tuple has one and only one distinct key r.p and n attribute columns r.I ₁ ，r.I ₂ ，…，r.I _n Then, the initial population number represents the number of cuckoos used for finding the optimal solution, then the cuckoo function optimal solution is found, and then the watermark u = (u) to be embedded ₁ ,u ₂ ,...,u _k ) And u belongs to {0,1}, k is less than or equal to m, and watermark insertion position information is obtained according to watermark preference selection obtained by calculation of the optimal solution of the Cuckoo letter.

6. The method for transmitting information of natural electromagnetic pulse vector signal energy spectrum according to claim 5, characterized in that: the cuckoo function aims at minimizing distortion after embedding the watermark, and the cuckoo algorithm selects the best position for embedding the watermark for each tuple.

7. An information transmission system of a natural electromagnetic pulse vector signal energy spectrum is characterized in that: the transmission system is an operation system of the information transmission method of the natural electromagnetic pulse vector signal energy spectrum, which is defined by any one of claims 1 to 6, and comprises a preprocessing module, an input module, a watermark embedding module and an output module;

an optical multi-carrier is generated in the preprocessing module through a laser and a multi-carrier signal generator; then, a demultiplexer is used for decomposing the optical multi-carrier into multi-path optical wave signals;

the input module comprises a double-parallel Mach-Zehnder modulator, and two groups of vector signals to be transmitted and one path of light wave signal simultaneously enter the double-parallel Mach-Zehnder modulator for modulation;

the watermark embedding module is mainly used for embedding watermarks into the light wave signals modulated by the double parallel Mach-Zehnder modulators and completing encryption;

and the output module outputs the first vector signal and the second vector signal after embedding the watermark through the coherent detector, and the first vector signal and the second vector signal are modulated through the double parallel Mach-Zehnder modulator again in the coherent detector.

8. The system according to claim 7, wherein the system further comprises: the preprocessing module, the input module, the watermark embedding module and the output module are in communication connection through a single mode fiber.

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