SAR two-dimensional multi-phase segmented modulation interference method based on time modulation metasurface

Abstract

The application discloses a SAR two-dimensional multi-phase segmented modulation interference method based on time modulation metasurface, and relates to the technical field of signal processing. In the application, each metasurface unit is combined with two open reverse and symmetrical metal square rings and varactor diodes, so that the phase, amplitude and polarization state of the incident electromagnetic wave are flexibly regulated and controlled. The dynamic regulation and control capability enables the metasurface to adjust the response to the electromagnetic wave in real time according to the requirements of different application scenarios, so that the electromagnetic environment is accurately controlled. The structure of the application only uses two open reverse and symmetrical metal square rings and varactor diodes, so that the phase, amplitude and polarization state of the incident electromagnetic wave are flexibly regulated and controlled, and the electromagnetic environment is accurately controlled. Compared with the traditional complex time modulation metasurface, the modulation performance of the time modulation metasurface is greatly improved, and high-precision SAR radar interference is realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of signal processing, in particular to a SAR two-dimensional multi-phase segmented modulation jamming method and device based on time-modulated metasurface, equipment and medium. BACKGROUND

[0002] Synthetic Aperture Radar (SAR) is a kind of high-resolution imaging radar, which has the characteristics of all-weather, all-day and long-distance, and has an indisputable advantage in military reconnaissance applications; in order to cope with the potential threat of enemy SAR reconnaissance systems in modern electronic warfare, the jamming method for SAR imaging has attracted widespread attention, in order to effectively hide the important feature information of high-value targets.

[0003] Traditional SAR jamming methods can be divided into active jamming and passive jamming; among them, active jamming is to transmit jamming signals to the SAR system by using active jammers, which generally requires high-power jammers and sensing devices, has high cost, and has the risk of exposing the target area; passive jamming method does not actively emit electromagnetic signals, but generates strong echo signals of false targets through passive devices such as corner reflectors and chaff, to interfere with the SAR reconnaissance of the protected target, however, these passive devices lack flexibility and the interference effect is limited.

[0004] With the rapid development of electromagnetic metasurface technology, time-modulated metasurfaces have the ability to flexibly modulate the amplitude, phase, frequency and other characteristics of incident electromagnetic waves in real time, so using metasurface technology to realize the modulation of incident electromagnetic waves has become a development trend; the time-modulated metasurfaces at the present stage usually include voltage-modulated metasurfaces, light-modulated metasurfaces and temperature-modulated metasurfaces, the voltage-modulated metasurfaces usually modulate the electromagnetic properties of the metasurface units by changing the voltage applied to the metasurface units, the light-modulated metasurfaces use the photoelectric effect of photosensitive materials (such as photoconductive materials, photoelectric materials, etc.) to modulate the electromagnetic properties of the metasurface by changing the light intensity or wavelength, and the temperature-modulated metasurfaces use the thermal expansion and contraction effect or thermal sensitivity effect of materials to modulate the electromagnetic properties of the metasurface by changing the temperature, but such time-modulated metasurfaces usually need to design relatively complex structures to continuously modulate various characteristics of the time-modulated metasurface in the process of modulating electromagnetic waves, which reduces the modulation performance of the modulation, making it difficult to realize high-precision SAR radar jamming. SUMMARY

[0005] The embodiment of the present application provides a SAR two-dimensional multi-phase segmented modulation interference method based on a time modulation metasurface, which can solve the problem that a time modulation metasurface at the present stage needs to be designed with a relatively complex structure to continuously modulate various characteristics of the time modulation metasurface in the process of modulating electromagnetic waves, thereby reducing the modulation performance of the modulation and making it difficult to realize high-precision SAR radar interference.

[0006] The embodiment of the present application provides a SAR two-dimensional multi-phase segmented modulation interference method based on a time modulation metasurface, which can solve the problem that a time modulation metasurface at the present stage needs to be designed with a relatively complex structure to continuously modulate various characteristics of the time modulation metasurface in the process of modulating electromagnetic waves, thereby reducing the modulation performance of the modulation and making it difficult to realize high-precision SAR radar interference.

[0007] The embodiment of the present application provides a SAR two-dimensional multi-phase segmented modulation interference method based on a time modulation metasurface, which can solve the problem that a time modulation metasurface at the present stage needs to be designed with a relatively complex structure to continuously modulate various characteristics of the time modulation metasurface in the process of modulating electromagnetic waves, thereby reducing the modulation performance of the modulation and making it difficult to realize high-precision SAR radar interference.

[0008] The super surface unit comprises a first substrate, and two open reverse and symmetrical metal square rings are arranged on the top surface of the first substrate, and a varactor diode is arranged between the two metal square rings; the metal square rings are used for regulating the phase, amplitude and polarization state of the electromagnetic wave incident on the super surface unit, and reflecting or transmitting the electromagnetic wave;

[0009] By changing the voltage applied to the two metal square rings, the voltage on both sides of the varactor diode is changed, the equivalent capacitance of the varactor diode is regulated in real time, and the phase of the electromagnetic wave incident on the super surface unit is regulated to be continuously changed;

[0010] The time modulation metasurface receives the transmission signal of the SAR radar, performs two-dimensional intra-pulse and inter-pulse multi-phase segmented modulation on the transmission signal, and reflects the transmission signal, so as to deceive and interfere with the SAR radar through the reflected signal.

[0011] Preferably, the bottom surface of the first substrate is provided with a metal grounding plate, the bottom surface of the metal grounding plate is provided with a second substrate, the bottom surface of the second substrate is provided with two bias lines, and the two bias lines are respectively connected with the corresponding metal square rings through two metal vias arranged on the first substrate;

[0012] The metal grounding plate is located on the bottom surface of the first substrate and is used for electromagnetic shielding and grounding, and simultaneously prevents leakage and interference of the electromagnetic wave in the super surface unit;

[0013] The bias line is located on the bottom surface of the second substrate and is used for providing a direct-current voltage or current to the metal square ring to change the capacitance value of the varactor diode, so as to dynamically control the super surface electromagnetic wave regulation.

[0014] Preferably, the two-dimensional intra-pulse and inter-pulse multi-phase segmented modulation on the transmission signal comprises:

[0015] When the transmitting signal of the SAR radar is incident to the time-modulated metasurface, by changing the voltage applied on the two bias lines, the voltage on both sides of the varactor diode is changed to real-time control the equivalent capacitance of the varactor diode, and the phase of the electromagnetic wave signal incident to the time-modulated metasurface is respectively two-dimensionally pulse-in multi-phase segmented modulation and slow-time two-dimensionally pulse-out multi-phase segmented modulation, and a pulse-in multi-phase segmented modulation signal and a pulse-out multi-phase segmented modulation signal are respectively obtained;

[0016] The pulse-in multi-phase segmented modulation signal and the pulse-out multi-phase segmented modulation signal are respectively:

[0017]

[0018] Wherein: represents the pulse-in multi-phase segmented modulation signal; p2(t m represents the pulse-out multi-phase segmented modulation signal; * represents convolution operation; τ1, T1, f1 = 1 / T1, φ p1 , P1, N1 respectively represent the segmented duration, modulation period, modulation frequency, modulation phase, pulse-in phase segment number, and repetition number of the pulse-in multi-phase segmented modulation signal; τ2, T2, f2 = 1 / T2, φ p2 , P2, N2 respectively represent the segmented duration, modulation period, modulation frequency, modulation phase, pulse-out phase segment number, and repetition number of the pulse-out multi-phase segmented modulation signal;

[0019] The two-dimensionally multi-phase segmented modulation signal is:

[0020]

[0021] Wherein: t m represents slow time; represents the two-dimensionally multi-phase segmented modulation signal.

[0022] Preferably, the forming of the reflected signal comprises:

[0023] The time-modulated metasurface on the stationary target receives the transmitting signal of the SAR radar, and performs two-dimensionally pulse-in multi-phase segmented modulation and slow-time two-dimensionally pulse-out multi-phase segmented modulation on the transmitting signal, to obtain a pulse-in multi-phase segmented modulation signal and a pulse-out multi-phase segmented modulation signal, and form a two-dimensionally multi-phase segmented modulation signal;

[0024] The frequency spectrum of the two-dimensional multi-phase segment modulation signal is extracted in the frequency domain, the frequency spectrum of the two-dimensional multi-phase segment modulation signal is periodically weighted and expanded in the range direction and the azimuth direction of the protected target, a plurality of different frequency spectrums generated in the range direction and the azimuth direction are sequentially replaced with the frequency spectrum of the two-dimensional multi-phase segment modulation signal, a plurality of harmonic components of the two-dimensional multi-phase segment modulation signal are formed in the range direction and the azimuth direction respectively, and the plurality of harmonic components in the range direction and the azimuth direction are synthesized into a two-dimensional multi-phase segment jamming signal, and the two-dimensional multi-phase segment jamming signal is a reflected signal.

[0025] Preferably, the two-dimensional multi-phase segment jamming signal is:

[0026]

[0027] Wherein f1 represents the modulation frequency of the intra-pulse multi-phase segment modulation signal; and f2 represents the modulation frequency of the inter-pulse multi-phase segment modulation signal.

[0028] Preferably, the deception jamming to the SAR radar comprises:

[0029] The SAR radar receives the two-dimensional multi-phase segment jamming signal, and performs range direction matched filtering, range migration correction and clutter suppression on the jamming signal, so as to form a false target array along the range direction and the azimuth direction of the protected target in the jamming image, and realize jamming to the SAR radar.

[0030] Wherein the offset of the mth-nth false target in the range dimension and the azimuth dimension is respectively:

[0031]

[0032] Wherein f1 represents the modulation frequency of the intra-pulse multi-phase segment modulation signal; f2 represents the modulation frequency of the inter-pulse multi-phase segment modulation signal; γ represents the range direction Doppler frequency modulation; μ represents the azimuth direction Doppler frequency modulation; λ represents the wavelength; and c represents the speed of light.

[0033] The embodiment of the present application also provides a SAR two-dimensional multi-phase segment modulation jamming device based on a time modulation metasurface, comprising:

[0034] A design module is used for designing a time modulation metasurface and installing the time modulation metasurface on the surface of a protected target; the time modulation metasurface is composed of a plurality of periodically arranged metasurface units;

[0035] The metasurface unit comprises a first substrate, the top surface of the first substrate is provided with two open metal square rings which are reversely arranged and symmetrical, and a varactor diode is arranged between the two metal square rings; the metal square rings are used for regulating the phase, amplitude and polarization state of the electromagnetic wave incident on the metasurface unit, and reflecting or transmitting the electromagnetic wave;

[0036] By changing the voltage applied on the two metal square rings, the voltage on both sides of the varactor diode is changed, and the equivalent capacitance of the varactor diode is real-time regulated, so that the phase of the electromagnetic wave incident on the metasurface unit is regulated to be continuously variable;

[0037] The SAR radar interference module modulates the transmission signal of the SAR radar received by the time-modulated metasurface in two dimensions, performs two-dimensional intra-pulse and inter-pulse multi-phase segmentation modulation on the transmission signal, and reflects the modulated signal, so as to perform deception jamming on the SAR radar.

[0038] The embodiment of the present application also provides an electronic device comprising a memory and a processor;

[0039] The memory is used for storing a computer program;

[0040] The processor is used for executing the computer program stored in the memory, so as to realize the steps of the SAR two-dimensional multi-phase segmentation modulation interference method based on the time-modulated metasurface.

[0041] The embodiment of the present application also provides a computer readable storage medium, characterized by being used for storing a computer program, and the computer program is executed by a processor to realize the steps of the SAR two-dimensional multi-phase segmentation modulation interference method based on the time-modulated metasurface.

[0042] The embodiment of the present application provides the SAR two-dimensional multi-phase segmentation modulation interference method based on the time-modulated metasurface, and the beneficial effects are as follows compared with the prior art:

[0043] Each metasurface unit in the present application realizes flexible regulation of the phase, amplitude and polarization state of the incident electromagnetic wave through the combination of two open reverse and symmetrical metal square rings and the varactor diode, and the dynamic regulation capability enables the metasurface to adjust the response to the electromagnetic wave in real time according to the requirements of different application scenarios, so as to realize accurate control of the electromagnetic environment; the structure of the present application only uses two open reverse and symmetrical metal square rings and the varactor diode, and can realize flexible regulation of the phase, amplitude and polarization state of the incident electromagnetic wave, and accurate control of the electromagnetic environment, compared with the traditional complex time-modulated metasurface, the modulation performance of the time-modulated metasurface is greatly improved, and high-precision SAR radar interference is realized.

[0044] Moreover, when the time-modulated metasurface receives the transmission signal of the SAR radar, it can perform two-dimensional intra-pulse and inter-pulse multi-phase segmentation modulation on the signal, and reflect the modulated signal back, and the carefully designed reflected signal can simulate a radar image different from the real target, so as to produce deception jamming on the SAR radar, and effectively reduce the detection and recognition ability of the radar on the target, and protect the protected target from the threat of the radar. BRIEF DESCRIPTION OF DRAWINGS

[0045] Figure 1 The overall flowchart of the SAR two-dimensional multi-phase segmented modulation interference method based on the time modulation metasurface provided by the embodiment of the present application is shown in the figure.

[0046] Figure 2 The interference model diagram of the SAR two-dimensional multi-phase segmented modulation interference method based on the time modulation metasurface provided by the embodiment of the present application is shown in the figure.

[0047] Figure 3 The design diagram of the time modulation metasurface of the SAR two-dimensional multi-phase segmented modulation interference method based on the time modulation metasurface provided by the embodiment of the present application is shown in the figure.

[0048] Figure 4 The original SAR imaging result diagram of the SAR two-dimensional multi-phase segmented modulation interference method based on the time modulation metasurface provided by the embodiment of the present application in the case of no interference is shown in the figure.

[0049] Figure 5 The intra-pulse modulation phase distribution diagram of the SAR two-dimensional multi-phase segmented modulation interference method based on the time modulation metasurface provided by the embodiment of the present application is shown in the figure.

[0050] Figure 6 The inter-pulse modulation phase distribution diagram of the SAR two-dimensional multi-phase segmented modulation interference method based on the time modulation metasurface provided by the embodiment of the present application is shown in the figure.

[0051] Figure 7 The interference imaging result diagram of the SAR two-dimensional multi-phase segmented modulation interference method based on the time modulation metasurface provided by the embodiment of the present application is shown in the figure. DETAILED DESCRIPTION

[0052] In order to make the above objectives, features and advantages of the present application more apparent, specific embodiments of the present application will be described in detail below with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, the present application can be practiced in a variety of ways other than those described herein without departing from the spirit of the present application, and it will be apparent to those skilled in the art that similar modifications of structure and method that are not specifically described can be resorted to without departing from the spirit of the present application. Therefore, the present application is not limited to the specific embodiments disclosed below.

[0053] Reference Figure 1 The SAR two-dimensional multi-phase segmented modulation interference method based on the time modulation metasurface provided by the embodiment of the present application comprises the following steps:

[0054] Step one: construction of the SAR imaging interference model based on the time modulation metasurface.

[0055] Step two: design of the time modulation metasurface.

[0056] Step three: Establishment and generation of two-dimensional multi-phase segmented modulation signal model of time modulation metasurface.

[0057] Step four: SAR imaging processing and imaging interference effect analysis.

[0058] The construction of the SAR imaging interference model in step one is as follows:

[0059] The SAR imaging interference model based on time modulation metasurface is shown in Figure 2 ; A two-dimensional rectangular coordinate system XOR is established on the SAR data acquisition plane. The SAR system moves along the X-axis at a constant speed V, and the distance direction perpendicular to the flight trajectory to the center of the observation scene is denoted as the R-axis; The time modulation metasurface is placed on the surface p t (x0, R0) of the protected target in the observation scene, where (x0, R0) represents the target position; The instantaneous slant range between the SAR system and the protected target can be represented as:

[0060]

[0061] where: t m represents the azimuth slow time; R B = minR(t m ).

[0062] Assume that the LFM signal transmitted by the SAR system is represented as:

[0063]

[0064] where: represents the range fast time; T r represents the pulse width; rect(·) represents the rectangular function; f0 represents the center frequency of the transmitted signal; μ represents the frequency modulation rate of the transmitted LFM signal.

[0065] The time modulation metasurface on the target surface intercepts the radar transmitted signal and performs interference modulation; Since the metasurface itself does not actively radiate high-power signals to the outside world, it avoids the shortcomings of traditional active interference methods, which are high in cost and easy to expose the target area; Under the control of external bias voltage, the time metasurface can realize real-time modulation of the phase and amplitude information of the transmitted signal, and transfer the modulated signal to the SAR imaging system. The SAR system receives the interference echo signal and performs detection and demodulation processing, and its complex baseband interference signal can be represented as:

[0066]

[0067] where: represents the modulation signal generated based on the time modulation metasurface; represents the unmodulated echo signal, whose expression is:

[0068]

[0069] wherein: A represents the complex reflection coefficient of the target; T a represents the synthetic aperture time; λ and c represent the wavelength and the speed of light, respectively.

[0070] Because the phase or amplitude information in the SAR echo signal is destroyed by the modulated signal, false targets or defocused images appear in the SAR image after imaging processing, effectively realizing SAR imaging jamming.

[0071] The design of the time-modulated metasurface in step two is as follows:

[0072] First, the reverse open metal structure is designed, and a lumped element, a varactor diode, is added between the two open metal structures. By adjusting the voltage on both sides of the varactor diode, the change of the equivalent capacitance is realized, so that the phase of the incident electromagnetic wave is continuously changed. The designed electromagnetic metasurface unit structure and array structure are shown in Figure 3 The unit structure is two-dimensionally periodically translated to realize the array structure layout, thereby realizing the complete two-dimensional electromagnetic metasurface array structure.

[0073] The establishment and generation of the two-dimensional multi-phase segmented modulation signal model in step three are as follows:

[0074] The two-dimensional multi-phase segmented modulation signal based on the time-modulated metasurface can be expressed as:

[0075]

[0076] wherein: the intra-pulse multi-phase segmented modulation signal and the inter-pulse multi-phase segmented modulation signal p2(t m ) are respectively expressed as:

[0077]

[0078] wherein: * represents convolution operation; τ1, T1, f1 = 1 / T1, φ p1 , P1, N1 represent the segmented duration, modulation period, modulation frequency, modulation phase, intra-pulse phase segment number, and repetition number of the intra-pulse modulation signal, respectively; τ2, T2, f2 = 1 / T2, φ p2 , P2, N2 represent the segmented duration, modulation period, modulation frequency, modulation phase, inter-pulse phase segment number, and repetition number of the inter-pulse modulation signal, respectively.

[0079] The frequency domain expressions of p1(t m ) and p2(t m ) are respectively:

[0080]

[0081] Therefore, the interference signal in two-dimensional frequency domain can be expressed as:

[0082]

[0083] Wherein:

[0084] As can be seen from the above formula, after two-dimensional multi-phase segmentation modulation processing, the frequency spectrum of the interference signal is periodically weighted and expanded along the range direction and the azimuth direction, and the periods of the range direction and the azimuth direction are the modulation frequencies f1 and f2, and the amplitudes are jointly modulated by multiple phases.

[0085] The fourth step of SAR imaging processing and imaging interference effect analysis is specifically:

[0086] The SAR interference signal is subjected to range-Doppler SAR imaging processing, and the interference signal after range matching filter processing and range migration correction can be expressed as:

[0087]

[0088] Wherein: B r represents the transmission signal bandwidth; represents the upward rounding.

[0089] The above interference signal is subjected to azimuth matching filter processing to obtain the final interference SAR image, and its expression is:

[0090]

[0091] Wherein: B a represents the signal Doppler bandwidth; γ represents the Doppler frequency modulation;

[0092] It can be seen that (2N+1)×(2M+1) false targets are generated in the interference SAR image, and the offset of the m-n false target in the range dimension and the azimuth dimension can be expressed as:

[0093]

[0094] The specific test is:

[0095] One reference target RT (0m, 0m) and three protected targets [PT1 (100m, -200m), PT2 (200m, 500m), and PT3 (-50m, 300m)] are set at the center of the imaging scene; range-Doppler SAR imaging processing is performed on the unmodulated radar echo to obtain the unmodulated raw SAR imaging result, such as... Figure 4 As shown, four targets with high focus quality can be observed in the SAR image.

[0096] Two-dimensional multi-phase segmented modulation of the echo signal from the protected target was performed using a time-modulated metasurface. The intra-pulse and inter-pulse modulation frequencies were set to f1 = 504.95 kHz and f2 = 39.28 Hz, respectively, and the intra-pulse and inter-pulse segmented phases were set to φ. p1 =0, 0.3π, 0.6π, π and φ q2 =0, 0.5π, 0.8π, π, with intra-pulse modulation phase and inter-pulse modulation phase as follows: Figure 5 and Figure 6 As shown; after range-Doppler imaging processing, the interference imaging result is obtained, as follows. Figure 7 As shown, it can be seen that after two-dimensional multi-phase segmented modulation processing based on time-modulated metasurface, the protected target PTi, (i=1,2,3) generates a two-dimensional false target array with a topological structure similar to the protected target. The distance and azimuth offset of each false target are proportional to the modulation frequency. Therefore, the method designed in this invention has high flexibility, high fidelity and low cost interference imaging effect.

[0097] This invention utilizes a time-modulated metasurface to generate a two-dimensional multi-phase segmented modulation signal through an external control system, thereby achieving real-time phase modulation of radar signals to generate SAR interference signals. Through processing the SAR interference signals, theoretical analysis and experimental results show that this invention can generate a two-dimensional false target array with flexible and controllable range and azimuth positions and a topological structure similar to the protected target. It has high flexibility, high fidelity, and low cost interference imaging effects and has strong practical application value.

[0098] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A method for SAR two-dimensional multi-phase segment modulation jamming based on time modulation metasurface, characterized in that, The method comprises the following steps: designing a time modulation metasurface and installing it on a protected target surface; the time modulation metasurface is composed of a plurality of periodically arranged metasurface units; the metasurface unit comprises a first substrate, the top surface of the first substrate is provided with two open reverse and symmetrical metal square rings, and a varactor diode is arranged between the two metal square rings; the metal square rings are used for regulating the phase, amplitude and polarization state of the electromagnetic wave incident on the metasurface unit, and reflecting or transmitting the electromagnetic wave; by changing the voltage applied to the two metal square rings, the voltage on both sides of the varactor diode is changed, the equivalent capacitance of the varactor diode is regulated in real time, and the phase of the electromagnetic wave incident on the metasurface unit is regulated to be continuously changed; the time modulation metasurface receives the transmission signal of the SAR radar, performs two-dimensional intra-pulse and inter-pulse multi-phase segmented modulation on the transmission signal, and reflects the transmission signal, thereby cheating and interfering with the SAR radar through the reflected signal; the bottom surface of the first substrate is provided with a metal ground plate, the bottom surface of the metal ground plate is provided with a second substrate, the bottom surface of the second substrate is provided with two bias lines, and the two bias lines are respectively connected with the corresponding metal square ring through two metal vias arranged on the first substrate; the metal ground plate is located on the bottom surface of the first substrate, and is used for electromagnetic shielding and grounding, and simultaneously preventing leakage and interference of the electromagnetic wave in the metasurface unit; the bias lines are located on the bottom surface of the second substrate, and are used for providing a direct current voltage or current to the metal square ring to change the capacitance value of the varactor diode, so as to dynamically control the metasurface electromagnetic wave regulation; the two-dimensional intra-pulse and inter-pulse multi-phase segmented modulation on the transmission signal comprises: when the transmission signal of the SAR radar is incident on the time modulation metasurface, by changing the voltage applied to the two bias lines, the voltage on both sides of the varactor diode is changed, so as to regulate the equivalent capacitance of the varactor diode in real time, and the phase of the electromagnetic wave signal incident on the time modulation metasurface is respectively two-dimensional intra-pulse multi-phase segmented modulation and slow time two-dimensional inter-pulse multi-phase segmented modulation, and intra-pulse multi-phase segmented modulation signals and inter-pulse multi-phase segmented modulation signals are respectively obtained; the intra-pulse multi-phase segmented modulation signal and the inter-pulse multi-phase segmented modulation signal are respectively: ； wherein: represents an inter-pulse multi-phase segmented modulation signal; represents an inter-pulse multi-phase segmented modulation signal; represents a convolution operation; respectively represent a segment duration, a modulation period, a modulation frequency, a modulation phase, a number of intra-pulse phase segments, a number of repetitions of the intra-pulse multi-phase segmented modulation signal; respectively represent a segment duration, a modulation period, a modulation frequency, a modulation phase, a number of inter-pulse phase segments, a number of repetitions of the inter-pulse multi-phase segmented modulation signal; according to the intra-pulse multi-phase segmented modulation signal and the inter-pulse multi-phase segmented modulation signal, a two-dimensional multi-phase segmented modulation signal is obtained, and the two-dimensional multi-phase segmented modulation signal is: ； wherein: denotes a slow time; denotes a two-dimensional multi-phase segmented modulation signal; the formation of the reflected signal comprises: the time modulation metasurface on the stationary target receives the transmission signal of the SAR radar, and respectively performs two-dimensional intra-pulse multi-phase segmented modulation and slow time two-dimensional inter-pulse multi-phase segmented modulation on the transmission signal, obtains intra-pulse multi-phase segmented modulation signals and inter-pulse multi-phase segmented modulation signals, and forms a two-dimensional multi-phase segmented modulation signal; The frequency spectrum of the two-dimensional multi-phase segment modulation signal is extracted in the frequency domain, the frequency spectrum of the two-dimensional multi-phase segment modulation signal is periodically weighted and expanded in the range direction and the azimuth direction of the protected target, a plurality of different frequency spectrums generated in the range direction and the azimuth direction are sequentially replaced with the frequency spectrum of the two-dimensional multi-phase segment modulation signal, a plurality of harmonic components of the two-dimensional multi-phase segment modulation signal are formed in the range direction and the azimuth direction, respectively, and the plurality of harmonic components in the range direction and the azimuth direction are synthesized into a two-dimensional multi-phase segment jamming signal, the two-dimensional multi-phase segment jamming signal being a reflected signal; The two-dimensional multi-phase segment jamming signal is: ； wherein: f 1 represents the modulation frequency of the intrapulse multi-phase segmented modulated signal; f 2 represents the modulation frequency of the inter-pulse multi-phase segmented modulated signal; The method for performing deception jamming on the SAR radar comprises: The SAR radar receives the two-dimensional multi-phase segment jamming signal, and performs range matching filtering, range migration correction and clutter suppression on the jamming signal, thereby forming a false target array along the range direction and the azimuth direction of the protected target in the jamming image, and realizing jamming on the SAR radar; wherein the first false target has an offset in the range dimension and the azimuth dimension of: respectively. ； wherein: f 1 represents the modulation frequency of the intrapulse polyphase segmented modulated signal; f 2 represents the modulation frequency of the interpulse polyphase segmented modulated signal; represents the range Doppler frequency; The method comprises: represents the azimuth Doppler frequency; represents the wavelength; represents the speed of light.

2. The SAR two-dimensional multi-phase segment modulation jamming device based on time modulation metasurface, characterized in that, The design module is used for designing a time modulation metasurface and installing the time modulation metasurface on the surface of the protected target; The time modulation metasurface is composed of a plurality of periodically arranged metasurface units; The metasurface unit comprises a first substrate, the top surface of the first substrate is provided with two open metal square rings arranged in reverse and symmetrically, and a varactor diode is arranged between the two metal square rings; the metal square rings are used for regulating the phase, amplitude and polarization state of the electromagnetic wave incident on the metasurface unit, and reflecting or transmitting the electromagnetic wave; By changing the voltage applied to the two metal square rings, the voltage on both sides of the varactor diode is changed, the equivalent capacitance of the varactor diode is regulated in real time, and the phase of the electromagnetic wave incident on the metasurface unit is regulated to be continuously changed; The SAR radar jamming module receives the transmission signal of the SAR radar, performs two-dimensional intra-pulse and inter-pulse multi-phase segment modulation on the transmission signal, and reflects the transmission signal, thereby performing deception jamming on the SAR radar through the reflected signal. The memory and the processor are included; 3. An electronic device, comprising: The memory is used for storing a computer program; The processor is used for executing the computer program stored in the memory, and realizing the steps of the SAR two-dimensional multi-phase segment modulation jamming method based on the time modulation metasurface according to claim 1. The computer program is stored in the memory, and the computer program is executed by the processor to realize the steps of the SAR two-dimensional multi-phase segment modulation jamming method based on the time modulation metasurface according to claim 1.

4. A computer-readable storage medium, characterized in that, ​

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