An air-ground anti-interference transmission game method and system based on an active intelligent metasurface

Abstract

The application discloses an air-ground anti-interference transmission game method and system based on an active intelligent metasurface, and belongs to the technical field of wireless communication. The method specifically comprises the following steps: firstly, a communication scene with intelligent interferers, legal users, active RIS and unmanned aerial base stations is constructed; a game model is constructed based on a Stackelberg game and balanced analysis is conducted; the anti-interference performance of system transmission is optimized by formulating a competitive strategy between the interferers and the legal system; the upper and lower optimization problems in the game model are constructed by maximizing the interference utility function and the legal utility function respectively; the interference strategy of the interferer is obtained by solving the lower optimization problem model; the safe transmission strategy of the legal system is obtained by solving the upper optimization problem model; and the signal transmission performance of the legal system is improved when the wireless communication system faces intelligent interference attacks.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of wireless communication, and particularly relates to an air-ground anti-interference transmission game method and system based on an active intelligent metasurface. BACKGROUND

[0002] In the digital era, the popularity and dependence of wireless communication networks are increasing, but along with it, the network security threat is becoming increasingly serious. With the rapid development of technology, traditional malicious interference has evolved into more advanced intelligent interference. Intelligent interference not only inherits the characteristics of traditional interference, but also through real-time situation awareness, learning and decision-making capabilities, it adapts to different electromagnetic environments and responds to different interference objects. This interference, with its powerful cognitive ability, uses multi-level, multi-dimensional interference strategies to precisely, efficiently and covertly interfere with the target node communication system.

[0003] As an emerging electromagnetic wave regulation technology, the intelligent metasurface (Reconfigurable Intelligent Surface, RIS) technology regulates various physical properties of electromagnetic waves through digital coding, showing its application potential in communication, perception, imaging and other fields. The development of intelligent metasurface technology provides a new way for communication network anti-interference. However, the reflection channel introduced by passive RIS faces serious multiplicative fading problem. This "double-path loss" attenuation greatly limits the potential of RIS. In contrast, Active RIS can significantly improve system capacity and communication distance by actively amplifying signals, especially in atypical communication scenarios where direct links are weak or blocked.

[0004] As a hierarchical decision-making model, the Stackelberg game model was first proposed by economist Heinrich von Stackelberg to describe the competitive relationship between leaders and followers in economic markets. In this model, the leader makes the decision first, and the follower responds according to the leader's decision. In the field of communication network anti-interference, the Stackelberg game model can be used to describe the dynamic game process between legitimate users (leaders) and interferers (followers). By establishing a suitable game model, the behavior of the interferer can be effectively analyzed and predicted, thereby providing effective anti-interference strategies for legitimate users. SUMMARY

[0005] The technical problem to be solved by the present application is to provide an air-ground anti-interference transmission game method and system based on an active intelligent metasurface to solve the technical problem that intelligent interference is difficult to cope with in a wireless communication scenario.

[0006] The present application adopts the following technical solutions:

[0007] The air-ground anti-interference transmission game method based on an active intelligent metasurface comprises the following steps:

[0008] A communication scenario including an intelligent jammer, a legitimate user, an active RIS, and a UAV air base station is constructed.

[0009] The received signal at the receiver and the signal-to-interference ratio are determined, and a game model is constructed based on Stackelberg game to obtain the jammer utility function and the legitimate system utility function, respectively.

[0010] According to the obtained jammer utility function, a lower optimization problem in the game model is constructed to maximize the jammer utility function, and the jammer interference strategy is obtained by solving the lower optimization problem.

[0011] According to the obtained legitimate system utility function, an upper optimization problem in the game model is constructed to maximize the legitimate utility function, and the security transmission strategy of the legitimate system is obtained by solving the upper optimization problem.

[0012] Preferably, in the communication scenario, the number of antennas of the legitimate sender S, the receiver D, and the jammer J is N S , N D , and N J , respectively.

[0013] The channels from the legitimate sender S to the ARIS, from the legitimate sender S to the receiver D, from the jammer J to the ARIS, from the jammer J to the receiver D, and from the ARIS to the receiver D are respectively: wherein, is a symbol in a complex field, N is the number of reflecting elements, N S is the number of antennas of the legitimate transmitting end, N D is the number of antennas of the receiving end, and N J is the number of antennas of the jamming transmitting end.

[0014] The diagonal phase shift matrix of ARIS is Θ = diag(θ), where max{α1,α2,α3,.....,α n}≤α max ,α1,α2,α3,....,α n , is the transpose operation.

[0015] Preferably, the received signal and the received signal to interference ratio at the receiver D are respectively:

[0016]

[0017] where w D is the receive beamforming vector at the receiver D, x S , x J are the transmit signals at the transmitter and the interferer respectively, w S , w J are the transmit beamforming vectors at the transmitter and the interferer respectively, n R , n D are the background noise vectors at the ARIS and the receiver D respectively, is the conjugate transpose of the receive beamforming vector at the receiver D, y D is the received signal vector at the receiver, is the equivalent channel from the legitimate transmitter S to the receiver D, is the equivalent channel from the interferer J to the receiver D, H RD is the channel from the RIS to the receiver D, P J is the interference transmit power, P S is the legitimate transmit power, Θ is the diagonal phase shift matrix of ARIS, is the background noise at the ARIS.

[0018] Preferably, the interference transmitter utility function and the legitimate system utility function are respectively:

[0019] U J (w J ,P J ) = -SINR-C J P J

[0020] U L (w D ,w S , Θ, P S ) = SINR-C S P S

[0021] where C S , CJ is a linear coefficient, w D is a receive beamforming vector at receiver D, w S , w J are transmit beamforming vectors at the transmitter and the interferer, respectively, U L is a legitimate utility function, U J is an interference utility function, P S is a legitimate transmit power, P J is an interference transmit power, Θ is a diagonal phase shift matrix of ARIS, and SINR is a received signal-to-interference ratio.

[0022] Preferably, the lower optimization problem in the game model is constructed and solved with the objective of maximizing the interference utility function, to obtain the interference strategy of the jammer, specifically:

[0023] Fixing P J , w J is optimized; w is obtained by maximum ratio transmission (MRT);

[0024] Fixing w J , P J is optimized;

[0025] The optimal interference power P J is derived by setting the first derivative of the utility function to zero; and then the jammer obtains the interference strategy with P J as the transmit power and w J as the transmit beamforming vector.

[0026] Preferably, the optimal interference power P J is

[0027]

[0028] wherein, is the optimal interference power P S , P S is the legitimate transmit power, is the conjugate transpose of the receive beamforming vector at receiver D, is an equivalent channel from the legitimate transmitter S to receiver D, w S is the transmit beamforming vector at the transmitter, is the background noise at ARIS, H RD is a channel from RIS to receiver D, Θ is a diagonal phase shift matrix of ARIS, is the background noise at receiver D, C J is a cost coefficient in the interference utility function, is an equivalent channel from the jammer J to receiver D, is a maximum power limit for interference transmission.

[0029] Preferably, the utility function of the jammer is maximized:

[0030]

[0031] s.t.C1:||w J || 2 =1

[0032] C2:

[0033] where U J is the utility function of the jammer, w J is the transmit beamforming vector at the jammer, P J is the jamming transmit power, SINR is the received signal-to-interference ratio, C J is the cost coefficient in the utility function of the jammer, and is the maximum power limit of the jamming transmission.

[0034] Preferably, the upper optimization problem in the game model is constructed and solved with the objective of maximizing the legitimate utility function, to obtain the secure transmission strategy of the legitimate system, specifically:

[0035] fixing w D , w S , Θ, optimizing P S , P J ; introducing auxiliary variables convert the original problem into a convex optimization problem, and then solve u, P J using the CVX tool package, and then solve P S from P 2 = u S to obtain the power allocation of the legitimate transmission;

[0036] fixing P S , P J , w S , Θ, optimizing w D ; convert the original objective function into a generalized Rayleigh entropy and generalized eigenvalue problem, and solve

[0037] fixing P S , P J , w D , Θ, optimizing w S ; obtain

[0038] fixing P S , P J , w S , w D , optimizing Θ;

[0039] Integrating each sub-problem in a BCD framework, the overall optimization of the original problem is achieved, and the optimal strategy of active metasurface assisted secure transmission is obtained.

[0040] The overall optimization of the original problem is as follows:

[0041] U L (P S (t-1) ,w S (t-1) ,w D (t-1) ,Θ (t-1) )≤U L (P S (t) ,w S (t-1) ,w D (t-1) ,Θ (t-1) )≤U L (P S (t) ,w S (t) ,w D (t-1) ,Θ (t-1) )

[0042] ≤U L (P S (t) ,w S (t) ,w D (t) ,Θ (t-1) )≤U L (P S (t) ,w S (t) ,w D (t) ,Θ (t) )

[0043] wherein U L is a legal utility function, P S (t-1) is a legal transmit power of the t-1th iteration, w S (t-1) is a transmit beamforming vector of the t-1th iteration, w D (t-1) is a receive beamforming vector of the t-1th iteration, Θ (t-1) is a diagonal phase shift matrix of the ARIS of the t-1th iteration, P S (t) is a legal transmit power of the tth iteration, wS (t) is the transmit beamforming vector for the tth iteration, w D (t) is the receive beamforming vector for the tth iteration, Θ (t) is the diagonal phase shift matrix of the ARIS for the tth iteration.

[0044] Preferably, the utility function of the legitimate system is maximized:

[0045]

[0046] s.t.C3:

[0047] C4:

[0048] C5:||w D || 2 = 1,||w S || 2 = 1,||w J || 2 = 1

[0049] C6:

[0050] C7:

[0051] where w D is the receive beamforming vector at the receiver D, w S is the transmit beamforming vector at the transmitter, P S is the transmit power of the legitimate, Θ is the diagonal phase shift matrix of the ARIS, U L is the utility function of the legitimate, is the conjugate transpose of the receive beamforming vector at the receiver D, is the equivalent channel from the legitimate transmitter S to the receiver D, is the equivalent channel from the jammer J to the receiver D, w J is the transmit beamforming vector of the jammer J, is the background noise at the ARIS, H RD is the channel from the RIS to the receiver D, is the background noise at the receiver D, C S is the cost coefficient in the utility function of the legitimate, is the maximum power limit of the legitimate transmission, H SR is the channel from the legitimate transmitter S to the ARIS, H JR is the channel from the jammer J to the ARIS, is the maximum power limit of the ARIS, amax ARIS is the maximum amplification limit, J is a natural number set, J is the optimal transmit beamforming vector of the jammer, J is the optimal interference power, U J J is the interference utility function.

[0052] In a second aspect, an embodiment of the present application provides an air-ground anti-interference transmission game system based on an active intelligent metasurface, comprising:

[0053] A scene module constructs a communication scene including an intelligent jammer, a legal user, an active RIS, and a UAV air base station;

[0054] A function module determines a received signal at a receiver and a signal-to-interference ratio expression; and based on a Stackelberg game, a game model is constructed to obtain a jammer utility function and a legal system utility function;

[0055] An interference module, according to the obtained jammer utility function, constructs a lower optimization problem in the game model and solves it with the goal of maximizing the interference utility function, to obtain an interference strategy of the jammer;

[0056] A transmission module, according to the obtained legal system utility function, constructs an upper optimization problem in the game model and solves it with the goal of maximizing the legal utility function, to obtain a secure transmission strategy of the legal system.

[0057] In a third aspect, a computer device comprises a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor implements the steps of the above-mentioned air-ground anti-interference transmission game method based on an active intelligent metasurface.

[0058] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium comprising a computer program, which, when executed by a processor, implements the steps of the above-mentioned air-ground anti-interference transmission game method based on an active intelligent metasurface.

[0059] In a fifth aspect, a chip comprises a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor implements the steps of the above-mentioned air-ground anti-interference transmission game method based on an active intelligent metasurface.

[0060] In a sixth aspect, an embodiment of the present application provides an electronic device comprising a computer program, which, when executed by the electronic device, implements the steps of the above-mentioned air-ground anti-interference transmission game method based on an active intelligent metasurface.

[0061] Compared with the prior art, the present application has at least the following beneficial effects:

[0062] A space-ground anti-interference transmission game method based on an active intelligent metasurface considers a communication scenario with intelligent interference, deploys an active RIS in a legal communication link to improve system anti-interference performance, and uses a Stackelberg game framework to formulate an optimal strategy of the legal party to cope with intelligent interference to improve physical layer communication security; from the perspective of scenario optimization, the malicious node of intelligent interference uses its sensing capability to detect before interfering, dynamically changes its interference strategy to achieve more effective attacks, and it is difficult for the legal user to effectively resist the interference attack regardless of how the legal user defends; based on this, an anti-interference framework based on Stackelberg game is developed, an active RIS is deployed to increase the effective signal while weakening the impact of the interference signal, a Stackelberg hierarchical game model is used to describe the strategy interaction between the leader (legal user) and the follower (interferer), and the competitive strategy between the interferer and the legal system is formulated to optimize the anti-interference performance of signal transmission. Simulation results show that the method enables the legal user to use the first-mover advantage in the hierarchical game to improve the anti-interference performance and improve secure communication.

[0063] Further, a communication scenario is designed with intelligent interferers, legal users, active RIS, and unmanned aerial base stations, which conforms to the general characteristics of wireless communication in reality, is easy to generalize to real communication scenarios, and fully embodies the complexity and randomness of the communication scenario, improving the adaptability of the scheme to similar actual scenarios.

[0064] Further, the expressions of the received signal and the signal-to-interference ratio at the receiver are determined through analysis and derivation, laying the necessary conditions for calculating the security rate and providing a theoretical basis for subsequent problem model representation.

[0065] Further, a game model is constructed based on Stackelberg game and equilibrium analysis is performed, and the utility function expressions of the interferer and the legal system are obtained; the obtained SINR can be regarded as the reward of legal transmission, and the corresponding consumed power is regarded as the corresponding cost; the opposite of the legal user is regarded as the reward of the interferer, and the power consumed by the jammer for interference attack is regarded as the cost; the model is modeled in a simple form, providing a theoretical basis for subsequent problem model representation.

[0066] Further, the lower optimization problem in the game model is constructed with the goal of maximizing the interference utility function; the upper optimization problem in the game model is constructed with the goal of maximizing the legal utility function; the problem solving goal is clearly defined in a simple form, and the optimization variables and constraints are clearly defined, providing favorable conditions for subsequent problem solving.

[0067] Further, the lower-layer optimization problem model is solved to obtain the jamming strategy of the jammer, and the upper-layer optimization problem model is solved to obtain the safe transmission strategy of the legal system; in solving the two optimization problems, based on the backward induction method, firstly, the lower-layer problem related to the jamming is solved, and meanwhile it is assumed that the strategy at the legal user is fixed, and for the deployed intelligent jamming, the strategy can be changed according to the transmission of the legal system. But in the hierarchical game here, the follower exists, so the transmission strategy of the follower is calculated first. Then the strategy is taken as the known content of the upper-layer problem to solve the upper-layer problem. In this setting, the leader, that is, the legal party, can take advantage of the so-called first-mover advantage and be in a favorable position in the competition, thereby improving the security.

[0068] It can be understood that the beneficial effects of the above-mentioned second aspect to the sixth aspect can be referred to the related description in the first aspect, which will not be repeated here.

[0069] In summary, the Stackelberg hierarchical game model is used in the communication scenario with intelligent jamming in the application, in order to resist the intelligent jamming attack, the legal user carefully determines the transmission power to trade off between the obtained SINR and the lost cost; at the same time, the jammer needs to jointly optimize the detection and jamming to achieve the maximum deterioration; the security competition is described as a hierarchical game, the legal user is the leader, and the jammer is the follower; on the basis of the game equilibrium analysis, the strategy design of both parties is proposed; the simulation results show that the legal user uses the first-mover advantage in the hierarchical game to improve the secure communication.

[0070] The technical solutions of the application will be further described in detail below with the help of the accompanying drawings and embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0071] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed in the embodiments of the present application will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0072] Figure 1 The wireless transmission system model diagram constructed for the application;

[0073] Figure 2 The flowchart of the application;

[0074] Figure 3 The diagram of the influence of the price coefficient on the jamming utility;

[0075] Figure 4 The diagram of the influence of the price coefficient on the legal utility;

[0076] Figure 5 a schematic diagram of a computer device provided by an embodiment of the present application;

[0077] Figure 6 a block diagram of an electronic device provided by an embodiment of the present application.

[0078] wherein, 60. computer device; 61. processor; 62. memory; 63. computer program; 600. electronic device; 610. processing unit; 620. storage unit; 6201. random access storage unit; 6202. cache storage unit; 6203. read-only storage unit; 6204. program / utility; 6205. program modules; 630. bus; 640. display unit; 650. input / output interface; 660. network adapter; 700. external device. DETAILED DESCRIPTION

[0079] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative effort belong to the scope of protection of the present application.

[0080] In the description of the present application, it should be understood that the terms “comprise” and “include” indicate the presence of described features, integers, steps, operations, elements, and / or components, but do not exclude one or more other features, integers, steps, operations, elements, components, and / or sets thereof.

[0081] It should also be understood that the terms used in the specification of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application. As used in the specification and the appended claims of the present application, the singular forms “a”, “an” and “the” are intended to include the plural forms, unless the context clearly indicates otherwise.

[0082] It should be further understood that the term “and / or” used in the specification and the appended claims of the present application means any combination of one or more of the associated listed items and all possible combinations thereof, and includes these combinations, for example, A and / or B can represent three cases of A alone, A and B together, and B alone. In addition, the character “ / ” in the present application generally represents an “or” relationship between the front and rear associated objects.

[0083] It should be understood that, although the terms first, second, third, etc. can be adopted in the embodiments of the present application to describe the preset ranges, etc., these preset ranges should not be limited to these terms. These terms are only used to distinguish the preset ranges from each other. For example, the first preset range can also be referred to as the second preset range, and similarly, the second preset range can also be referred to as the first preset range without departing from the scope of the embodiments of the present application.

[0084] Depending on the context, the word "if" as used herein can be interpreted to mean "when" or "while" or "in response to determining" or "in response to detecting". Similarly, the phrase "if it is determined" or "if (a stated condition or event) is detected" can be interpreted to mean "when it is determined" or "in response to determining" or "when (a stated condition or event) is detected" or "in response to detecting (a stated condition or event)".

[0085] Various structural diagrams according to the disclosed embodiments of the present application are shown in the accompanying drawings. These diagrams are not drawn to scale, in which certain details are exaggerated for the purpose of clarity and certain details can be omitted. The shapes of various regions, layers and their relative sizes and positional relationships shown in the drawings are only exemplary, and in actuality, they can be deviated due to manufacturing tolerances or technical limitations, and regions / layers with different shapes, sizes and relative positions can be additionally designed according to actual needs by those skilled in the art.

[0086] The present application provides an air-ground anti-interference transmission game method based on active intelligent metasurface, based on the potential of active RIS in physical layer communication security, first, a communication scenario of intelligent jammer, legal user, active RIS and unmanned aerial base station is constructed; a game model is constructed based on Stackelberg game and equilibrium analysis is carried out, the competitive strategy between the jammer and the legal system is formulated to optimize the anti-interference performance of the system transmission; the upper and lower optimization problems in the game model are constructed by maximizing the interference utility function and the legal utility function respectively; the interference strategy of the jammer is obtained by solving the lower optimization problem model; the security transmission strategy of the legal system is obtained by solving the upper optimization problem model; the present application realizes the improvement of the signal transmission performance of the legal system when the wireless communication system faces intelligent jamming attack.

[0087] Embodiment 1

[0088] Please refer to Figure 2 The present application provides an air-ground anti-interference transmission game method based on active intelligent metasurface, comprising the following steps:

[0089] S1, a communication scenario containing intelligent jammer, legal user, active RIS and unmanned aerial base station is constructed;

[0090] Please refer to Figure 1 The wireless communication system model diagram constructed by the present application considers a scenario of a security communication system of an active intelligent metasurface assisted legal system anti-interference, in which a legal sender, a receiver and an interferer are represented by S, D and J respectively, and the number of antennas of S, D and J is N S ,N D ,N J , and the legal signal in the scenario is transmitted by a fixed-position unmanned aerial base station, and an ARIS with N reflecting elements is deployed to assist the system in resisting interference to maximize the receiving effect.

[0091] The channels from S to ARIS, S to D, J to ARIS, J to D, and ARIS to D are represented as:

[0092] The diagonal phase shift matrix of ARIS is defined as: Θ = diag(θ), Where max{α1,α2,α3,.....,α n}≤α max .

[0093] Suppose that the channel state information (CSI) of the involved channels is completely known at the base station.

[0094] S2, after analysis and derivation, determine the expressions of the received signal at the receiver and the signal-to-interference ratio;

[0095] The received signal at the receiver D is:

[0096] y D =(H RD ΘH SR +H SD )w S x S +(H RD ΘH JR +H JD )w J x J +H RD Θn R +n D

[0097] Where x S ,x J are the transmitted signals at the transmitting end and the interference, are the transmit beamforming vectors at the transmitting end and the interference, n and

[0098] For simplifying the formula, the following equivalent substitution is made:

[0099]

[0100] The actual received signal at D is:

[0101]

[0102] where, is the received beamforming vector at D.

[0103] The received signal-to-interference ratio at D is:

[0104]

[0105] Since the beamforming vector here does not change the signal size,

[0106] S3, based on Stackelberg game, a game model is constructed and equilibrium analysis is carried out, and the utility function expressions of the interferer and the legal system are obtained respectively;

[0107] The obtained SINR is regarded as the reward of the legal transmission, and the corresponding consumed power is regarded as the corresponding cost. Therefore, the reward and cost of the receiver are combined together as the basic utility function of the legal user:

[0108] U L (w D ,w S ,Θ,P S )=SINR-C S P S

[0109] where C S is a linear coefficient, w D is the received beamforming vector at receiver D, w S is the transmit beamforming vector of the transmitting end, U L is the legal utility function, P S is the legal transmit power, and Θ is the diagonal phase shift matrix of ARIS.

[0110] Similarly, the reward of the interferer can be considered as the opposite of the legal user, and the power consumed by the jammer for the interference attack is regarded as the cost. Therefore, the basic utility function of the jammer can be given as:

[0111] U J (w J ,P J )=-SINR-C JP J

[0112] S4, constructing a lower-layer optimization problem in the game model according to the expression obtained in step S3, with the goal of maximizing the interference utility function;

[0113] The goal of the lower-layer follower problem related to interference is determined as the maximization of the utility function of the jammer:

[0114]

[0115] s.t.C1:||w J || 2 =1

[0116] C2:

[0117] wherein C1 represents that the power of the transmission beam vector is 1; and C2 represents the maximum power limit of the interference transmission.

[0118] S5, solving the lower-layer optimization problem model to obtain the interference strategy of the jammer;

[0119] The optimization problem is divided into the following two sub-problems for solving, as follows:

[0120] S501, fixing P J , optimizing w J ; from the maximum ratio transmission (MRT):

[0121]

[0122] S502, fixing w J , optimizing P J ;

[0123] S503, deriving the optimal interference power by setting the first-order derivative of the utility function to zero;

[0124] Optimal interference power

[0125]

[0126] S6, constructing an upper-layer optimization problem in the game model according to the expression obtained in step S3, with the goal of maximizing the legal utility function;

[0127] The goal of the upper-layer leader problem related to the legal system is determined as the maximization of the utility function of the legal system:

[0128]

[0129] s.t.C3:

[0130] C4:

[0131] C5:||w D || 2 =1,||w S || 2 =1,||w J || 2 =1

[0132] C6:

[0133] C7:

[0134] where C3 is the constraint of the maximum value of BS transmit power; C4 is the maximum power limit at ARIS; C5 is that the power of each device's receiving or transmitting vector is 1; C6 is that the modulus of any element in the phase shift matrix does not exceed α max ; C7 is the interference strategy of the interferer which is preferentially obtained by the legal system as a leader in the hierarchical game.

[0135] S7, solve the upper optimization problem model to obtain the security transmission strategy of the legal system.

[0136] By using the block coordinate descent method, the optimization problem is divided into four sub-problems to be solved, that is, P S and P J ,w D ,w S ,Θ are solved respectively, as follows:

[0137] S701, fix w D ,w S ,Θ, optimize P S ,P J ; introduce auxiliary variables convert the original problem into a convex optimization problem, then use the CVX tool package to solve u, P J , and then solve P S =u 2 to solve P S , so as to obtain the power allocation of the legal transmission;

[0138] S702, fix P S ,P J ,w S ,Θ, optimize w D ; convert the original objective function into a generalized Rayleigh entropy and generalized eigenvalue problem, and solve to obtain:

[0139]

[0140] S703, fix P S ,P J ,w D ,Θ, optimize w S ; from Maximum Ratio Transmission (MRT) theory:

[0141]

[0142] S704, fix P S ,P J ,w S ,w D , optimize Θ;

[0143] Here, first, some complex terms are replaced by introducing auxiliary variables, such as: a joint convex function of the form is used to replace the fraction which is difficult to handle;

[0144] Then, the non-convex terms are approximated by the first-order Taylor expansion, such as: x 2 , and the like, so as to solve the problem of non-convex constraints.

[0145] The original problem is divided into four sub-problems, which are simplified and optimized respectively, and then integrated into a BCD framework to realize the overall optimization of the original problem:

[0146] U L (P S (t-1) ,w S (t-1) ,w D (t-1) ,Θ (t-1) )≤U L (P S (t) ,w S (t-1) ,w D (t-1) ,Θ (t-1) )≤U L (P S (t) ,w S (t) ,w D (t-1) ,Θ (t-1) )

[0147] ≤U L (P S (t) ,w S (t) ,w D (t) ,Θ (t-1) )≤U L (P S (t) ,w S (t) ,w D (t) ,Θ (t) )

[0148] The optimal strategy of the active metasurface assisted secure transmission can be obtained through such an iterative manner.

[0149] Those skilled in the art can understand that various aspects of the present application can be implemented as a system, a method or a program product. Therefore, various aspects of the present application can be embodied as a complete hardware implementation, a complete software implementation (including firmware, microcode, etc.), or a combination of hardware and software aspects, which can be collectively referred to as "circuitry", "module" or "platform" here.

[0150] Embodiment 2

[0151] The present application provides an air-ground anti-interference transmission game system based on active intelligent metasurface, which can be used to realize the air-ground anti-interference transmission game method based on active intelligent metasurface as described above. Specifically, the air-ground anti-interference transmission game system based on active intelligent metasurface includes a scene module, a function module, an interference module and a transmission module.

[0152] The scene module constructs a communication scene containing intelligent interferers, legitimate users, active RIS and unmanned aerial base stations.

[0153] The function module determines the received signal at the receiver and the signal-to-interference ratio expression, and constructs a game model based on Stackelberg game to obtain the utility function of the interferer and the utility function of the legitimate system.

[0154] The interference module, according to the obtained utility function of the interferer, constructs the lower optimization problem in the game model and solves it with the goal of maximizing the utility function of the interference, to obtain the interference strategy of the jammer.

[0155] The transmission module, according to the obtained utility function of the legitimate system, constructs the upper optimization problem in the game model and solves it with the goal of maximizing the utility function of the legitimate system, to obtain the secure transmission strategy of the legitimate system.

[0156] Embodiment 3

[0157] The application provides a terminal device, which comprises a processor and a memory for storing a computer program, wherein the computer program comprises program instructions, and the processor is used for executing the program instructions stored in the computer storage medium. The processor can be a central processing unit (CPU), and can also be other general-purpose processors, graphics processing units (GPUs), tensor processing units (TPUs), digital signal processors (DSPs), application specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components and the like, which are the computing core and control core of the terminal, and are suitable for implementing one or more instructions, and are particularly suitable for loading and executing one or more instructions to implement a corresponding method flow or a corresponding function. The processor in the embodiment of the application can be used for the operation of the air-ground anti-interference transmission game method based on an active intelligent metasurface, which comprises the following steps:

[0158] A communication scenario comprising an intelligent jammer, a legitimate user, an active RIS and a UAV air base station is constructed; a received signal at a receiver and a signal-to-interference ratio are determined; a game model is constructed based on a Stackelberg game to obtain a jammer utility function and a legitimate system utility function; according to the obtained jammer utility function, a lower optimization problem in the game model is constructed and solved with the aim of maximizing the jammer utility function, and a jamming strategy of the jammer is obtained; according to the obtained legitimate system utility function, an upper optimization problem in the game model is constructed and solved with the aim of maximizing the legitimate utility function, and a safe transmission strategy of the legitimate system is obtained.

[0159] Please refer to Figure 5 The terminal device is a computer device, and the computer device 60 of the embodiment comprises a processor 61, a memory 62 and a computer program 63 stored in the memory 62 and executable on the processor 61. The computer program 63 is executed by the processor 61 to implement the air-ground anti-interference transmission game method based on an active intelligent metasurface in the embodiment. To avoid repetition, details are not described herein. Alternatively, the computer program 63 is executed by the processor 61 to implement the functions of various models / units in the air-ground anti-interference transmission game system based on an active intelligent metasurface in the embodiment. To avoid repetition, details are not described herein.

[0160] The computer device 60 can be a desktop computer, a notebook computer, a palm computer, a cloud server, and the like. The computer device 60 can include, but is not limited to, a processor 61, a memory 62. Those skilled in the art can understand that the processor 61 and the memory 62 can be connected through a bus, and the bus can be a peripheral component interconnect (PCI) bus, a serial advanced technology attachment (SATA) bus, a universal serial bus (USB), or the like. Figure 5 The computer device 60 is only an example and does not constitute a limitation on the computer device 60, and can include more or fewer components than shown, or combine certain components, or include different components, for example, the computer device can also include an input / output device, a network access device, a bus, and the like.

[0161] The processor 61 can be a central processing unit (CPU), and can also be other general-purpose processors, graphics processing units (GPUs), tensor processing units (TPUs), digital signal processors (DSPs), application specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, and the like. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor.

[0162] The memory 62 can be an internal storage unit of the computer device 60, such as a hard disk or a memory of the computer device 60. The memory 62 can also be an external storage device of the computer device 60, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, and the like.

[0163] Further, the memory 62 can include both an internal storage unit and an external storage device of the computer device 60. The memory 62 is used to store computer programs and other programs and data required by the computer device. The memory 62 can also be used to temporarily store data that has been output or will be output.

[0164] Please refer to Figure 6The terminal device is an electronic device 600, which is in the form of a general computing device. Components of the electronic device can include, but are not limited to, at least one processing unit 610, at least one storage unit 620, a bus 630 that connects the different platform components, including the storage unit 620 and the processing unit 610, a display unit 640, and the like.

[0165] The storage unit stores program codes, which can be executed by the processing unit 610, so that the processing unit 610 performs the steps according to various exemplary embodiments of the present application described in the method part of the present specification. For example, the processing unit 610 can perform the steps as shown in Figure 2

[0166] The storage unit 620 can include a readable medium in the form of a volatile storage unit, such as a random access memory (RAM) 6201 and / or a cache memory unit 6202, and can further include a read-only memory (ROM) 6203.

[0167] The storage unit 620 can further include a program / utility 6204 having a set of program modules 6205, including but not limited to, an operating system, one or more application programs, other program modules, and program data, each of which can include implementation of a network environment, alone or in some combination.

[0168] The bus 630 can be one or more of several types of bus structures, including a storage unit bus or storage unit controller, a peripheral bus, a graphics acceleration port, a processing unit bus, or a local bus using any of a variety of bus architectures.

[0169] The electronic device 600 can also communicate with one or more external devices 700, such as a keyboard or pointing device, a Bluetooth device, etc., and can communicate with one or more devices that enable a user to interact with the electronic device 600. The electronic device 600 can also communicate with one or more devices that enable the electronic device 600 to communicate with one or more other computing devices. Such communication can be via an input / output interface 650. The electronic device 600 can also communicate with one or more networks, such as a local area network, a wide area network, and / or a public network, such as the Internet, via a network adapter 660. The network adapter 660 can communicate with the other modules of the electronic device 600 via the bus 630. It should be appreciated that, although not shown in the figure, other hardware and / or software modules can be used in connection with the electronic device 600, including but not limited to, microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, and data backup storage platforms, etc.

[0170] ​Embodiment 4

[0171] The present application also provides a storage medium, specifically a computer readable storage medium, which is a memory device in the terminal device, used for storing programs and data. It can be understood that the computer readable storage medium herein can include the built-in storage medium in the terminal device, and of course can also include the expansion storage medium supported by the terminal device, and can be any tangible medium containing or storing programs, which can be used by or in combination with an instruction execution system, device or apparatus. The computer readable storage medium provides a storage space, which stores the operating system of the terminal. Moreover, one or more instructions suitable for being loaded and executed by the processor are also stored in the storage space, which can be one or more computer programs (including program codes). It should be noted that more specific examples of the computer readable storage medium include an electrical connection with one or more wires, a portable disk, a hard disk, a random access memory, a read-only memory, an erasable programmable read-only memory, an optical fiber, a portable compact disk read-only memory, an optical storage device, a magnetic storage device, or any suitable combination of the above.

[0172] The computer readable storage medium also includes a data signal carried in the baseband or as a part of a carrier wave, in which readable program codes are borne. Such a propagated data signal can take various forms, including but not limited to electro-magnetic signal, optical signal or any suitable combination of the above. The readable storage medium can also be any readable medium other than the readable storage medium, which can send, propagate or transmit programs for use by or in combination with an instruction execution system, device or apparatus. The program codes contained on the readable storage medium can be transmitted by any suitable medium, including but not limited to wireless, wired, optical cable, radio frequency, etc., or any suitable combination of the above.

[0173] The program code for performing the operations of the present application can be written in any combination of one or more programming languages, including an object oriented programming language such as Java, C++, etc., and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The program code can execute entirely on the user's computing device, partly on the user's device, as a stand-alone software package, partly on the user's computing device and partly on a remote computing device or entirely on the remote computing device or server. In the latter scenario, the remote computing device can be connected to the user's computing device through any kind of network, including a local area network or a wide area network, or the connection can be made to an external computing device, such as through the Internet using an Internet Service Provider.

[0174] The one or more instructions stored in the computer readable storage medium can be loaded and executed by the processor to implement the corresponding steps of the method for air-ground anti-interference transmission game based on active intelligent metasurface in the above embodiments; the one or more instructions stored in the computer readable storage medium are loaded and executed by the processor to implement the following steps:

[0175] A communication scenario including an intelligent jammer, a legitimate user, an active RIS and a UAV air base station is constructed; a received signal at a receiver and a signal-to-interference ratio are determined; a game model is constructed based on a Stackelberg game to obtain a jammer utility function and a legitimate system utility function; according to the obtained jammer utility function, a lower optimization problem in the game model is constructed to maximize the jammer utility function, and is solved to obtain a jamming strategy of the jammer; according to the obtained legitimate system utility function, an upper optimization problem in the game model is constructed to maximize the legitimate utility function, and is solved to obtain a safe transmission strategy of the legitimate system.

[0176] The database involved in each embodiment provided in the present application can include at least one of a relational database and a non-relational database. The non-relational database can include a distributed database based on a blockchain, and the like, without being limited thereto. The processor involved in each embodiment provided in the present application can be a general-purpose processor, a central processing unit, a graphics processing unit, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, and the like, without being limited thereto.

[0177] To make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present application.

[0178] Please refer to Figure 3, the change of the interference utility function in the game equilibrium based on the legal transmit power and the interference power price coefficient is given. We can see that compared with the benchmark scheme without RIS assistance, the interference utility function of the proposed scheme is obviously smaller; when the interference coefficient increases, the interference utility function decreases, because for the jammer, the own coefficient is a negative factor for the utility function, and higher coefficient will lead to smaller utility function; when the legal coefficient increases, the interference utility function also decreases to a certain extent, because the increase of the legal coefficient will make the legal power decrease, and the interference power affected by the legal power also shows a decreasing trend, thereby leading to the decrease of the utility function.

[0179] Please refer to Figure 4 , the change of the legal utility function in the game equilibrium based on the legal transmit power and the interference power price coefficient is given. We can see that compared with the benchmark scheme without RIS assistance, the legal utility function of the proposed scheme is obviously larger; when the legal coefficient increases, the legal utility function decreases, because for the legal system, the own coefficient is a negative factor for the utility function, and higher coefficient will lead to smaller utility function; when the legal coefficient increases, the legal utility function increases, because the increase of the interference coefficient makes the interference power decrease while the legal transmit power increases, thereby leading to the certain increase of the legal utility function.

[0180] In summary, the active intelligent surface-based air-ground anti-interference transmission game method and system based on the active intelligent reflective surface assisted secure wireless communication under intelligent jamming attack. In particular, in order to resist intelligent jamming attacks that can dynamically change their own interference strategies to achieve more effective attacks, the present application carefully determines the transmit power of the legal user to balance between the obtained SINR and the lost cost. At the same time, the jammer needs to jointly optimize detection and interference to achieve the maximum deterioration. The security competition is described as a hierarchical game, and the legal user is the leader and the jammer is the follower. On the basis of game equilibrium analysis, the strategy design of both parties is proposed, and the legal user can use the first-mover advantage in the hierarchical game to improve the security communication.

[0181] Those skilled in the art can clearly understand that, for the convenience and brevity of description, only the above-mentioned division of each functional unit and module is exemplified, and in actual application, the above-mentioned functions can be completed by different functional units and modules according to needs, that is, the internal structure of the device is divided into different functional units or modules to complete all or part of the functions described above. Each functional unit and module in the embodiment can be integrated in one processing unit, or each unit can be physically present separately, or two or more units can be integrated in one unit. The above-mentioned integrated unit can be realized in the form of hardware or software. In addition, the specific names of each functional unit and module are only for the convenience of mutual distinction, and do not limit the protection scope of the present application. The specific working process of the units and modules in the above system can refer to the corresponding process in the foregoing method embodiments, which will not be described here.

[0182] In the above embodiments, the description of each embodiment has its own emphasis, and the parts not described or recorded in detail in a certain embodiment can be referred to the related description of other embodiments.

[0183] Those of ordinary skill in the art can realize that the units and algorithm steps of each example described in combination with the embodiments disclosed in the present application can be realized by electronic hardware or a combination of computer software and electronic hardware. Whether the functions are executed in hardware or software depends on the specific application and design constraints of the technical solution. Professional technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.

[0184] In the embodiments provided by the present application, it should be understood that the disclosed devices / terminals and methods can be implemented by other ways. For example, the device / terminal embodiments described above are only schematic, and the division of the modules or units is only a logical function division, and there can be another division way in actual implementation, for example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the displayed or discussed mutual coupling or direct coupling or communication connection between each displayed or discussed unit can be indirect coupling or communication connection through some interface, device or unit, and can be electrical, mechanical or other forms.

[0185] The units described as separate components can or can not be physically separated, and the components shown as units can or can not be physical units, that is, they can be located in one place, or can be distributed on multiple network units. Part or all of the units can be selected according to actual needs to achieve the purpose of the embodiment.

[0186] In addition, each functional unit in each embodiment of the present application can be integrated in one processing unit, or each unit can be physically present separately, or two or more units can be integrated in one unit. The integrated unit can be realized in the form of hardware or in the form of a software functional unit.

[0187] The integrated module / unit, if realized in the form of a software functional unit and sold or used as an independent product, can be stored in a computer-readable storage medium. Based on such understanding, all or part of the processes in the above-mentioned embodiment methods can also be completed by a computer program instructing related hardware, and the computer program can be stored in a computer-readable storage medium. The computer program can implement the steps of each method embodiment when executed by a processor. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or some intermediate forms. The computer-readable medium can include any entity or device capable of carrying the computer program code, recording medium, U disk, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signal, telecommunication signal, and software distribution medium, etc. It should be noted that the computer-readable medium can include or exclude contents according to the requirements of legislation and patent practice in the jurisdiction, for example, in some jurisdictions, according to legislation and patent practice, the computer-readable medium does not include electrical carrier signals and telecommunication signals.

[0188] The present application is described with reference to flowcharts and / or block diagrams according to the methods, devices, and computer program products of embodiments of the present application. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, and the combination of flows and / or blocks in the flowcharts and / or block diagrams can be implemented by computer program instructions. These computer program instructions can be provided to a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to produce a machine, so that the instructions executed by the computer or other programmable data processing devices produce a device that implements the functions specified in the flowcharts and / or block diagrams. Figure 1 The device that implements the functions specified in one flow or multiple flows and / or blocks Figure 1 The device that implements the functions specified in one flow or multiple flows and / or blocks

[0189] These computer program instructions can also be stored in a computer-readable storage medium that can guide the computer or other programmable data processing devices to work in a specific manner, so that the instructions stored in the computer-readable storage medium produce a manufactured product including instruction devices that implement the functions specified in the flowcharts and / or block diagrams. Figure 1one or more processes and / or blocks Figure 1 the function specified in the one or more blocks.

[0190] These computer program instructions can also be loaded into computer or other programmable data processing devices, so that a series of operational steps are performed on the computer or other programmable data processing devices to generate a computer-implemented process, so that the instructions executed on the computer or other programmable data processing devices provide a process for implementing the flowchart Figure 1 one or more processes and / or blocks Figure 1 the steps of the function specified in the one or more blocks.

[0191] The above is only to illustrate the technical idea of the present application, and cannot limit the protection scope of the present application. Any modification made according to the technical idea of the present application on the basis of the technical scheme falls within the protection scope of the claims of the present application.

Claims

1. A space-to-ground anti-interference transmission game method based on active intelligent metasurfaces, characterized in that, Includes the following steps: Construct a communication scenario that includes an intelligent jammer, a legitimate user, an active RIS (Remote Information Detection and Retrieval System), and a drone-based aerial base station. In this scenario, the number of antennas for the legitimate sender S, receiver D, and jammer J are N, respectively. S N D N J In this scenario, the legitimate signal is transmitted by a drone airborne base station at a fixed location, and an ARIS with N reflective elements is deployed to assist the system in resisting interference and thus maximize the reception effect. The channels from legitimate sender S to ARIS, from legitimate sender S to receiver D, from interferer J to ARIS, from interferer J to receiver D, and from ARIS to receiver D are as follows: , , , , ,in, The symbol for the complex field. The number of reflective elements, The legal number of transmitting antennas, This refers to the number of antennas at the receiving end. The number of antennas at the interfering transmitter; The diagonal phase shift matrix of ARIS is: , , ,in, , This is a transpose operation; Determine the received signal and signal-to-dryness ratio at the receiver; construct a game model based on Stackelberg game theory to obtain the utility function of the interfering party and the utility function of the legitimate system, respectively; The received signal and the received signal-to-dryness ratio at receiver D are respectively: in, Let D be the received beamforming vector. , These are the transmitted signals from the transmitting end and the jamming point, respectively. , These are the transmit beamforming vectors at the transmitting end and the interference point, respectively. , Let ARIS and receiver D represent the background noise vectors, respectively. This is the conjugate transpose of the received beamforming vector at receiver D. The signal vector received by the receiver. For an equivalent channel from a legitimate sender S to a receiver D, This is the equivalent channel from the interferer J to the receiver D. This is the channel from RIS to receiver D. To interfere with transmission power, For legal transmission power, This is the diagonal phase shift matrix of ARIS. This represents the background noise at ARIS. The background noise at receiver D; The utility functions of the disruptor and the legal system are as follows: in, The cost coefficient in the legal utility function; The cost coefficient in the interference utility function. Let D be the received beamforming vector. , These are the transmit beamforming vectors at the transmitting end and the interference point, respectively. For a valid utility function, Let be the interference utility function. For legal transmission power, To interfere with transmission power, This is the diagonal phase shift matrix of ARIS. For the received signal drying ratio; Based on the obtained interference utility function, the lower-level optimization problem in the game model is constructed and solved with the goal of maximizing the interference utility function, so as to obtain the interference strategy of the interference machine. Based on the obtained legal system utility function, the upper-level optimization problem in the game model is constructed and solved with the goal of maximizing the legal utility function, so as to obtain the safe transmission strategy of the legal system.

2. The air-to-ground anti-interference transmission game method based on active intelligent metasurfaces according to claim 1, characterized in that, The lower-level optimization problem in the game model is constructed and solved with the objective of maximizing the interference utility function, resulting in the interference strategy of the interference machine, specifically: fixed ,optimization ; derived from the maximum ratio transmission MRT It is used to solve higher-level optimization problems in game theory models; fixed ,optimization ; The optimal interference power is derived by setting the first derivative of the utility function to zero. Then the jammer was obtained. For transmission power, in Interference strategy for transmitting beamforming vectors.

3. The air-to-ground anti-interference transmission game method based on active intelligent metasurfaces according to claim 2, characterized in that, Optimal Interference Power : in, For optimal interference power, For legal transmission power, This is the conjugate transpose of the received beamforming vector at receiver D. For an equivalent channel from a legitimate sender S to a receiver D, The transmit beamforming vector at the transmitting end. This represents the background noise at ARIS. This is the channel from RIS to receiver D. This is the diagonal phase shift matrix of ARIS. The background noise at receiver D. The cost coefficient in the interference utility function. This is the equivalent channel from the interferer J to the receiver D. Maximum power limit for interference transmission.

4. The air-to-ground anti-interference transmission game method based on active intelligent metasurfaces according to claim 2, characterized in that, Maximizing the utility function of the jammer: in, Let be the utility function of the jammer. The transmitted beamforming vector at the interference point. To interfere with transmission power, For the received signal drying ratio, The cost coefficient in the interference utility function. Maximum power limit for interference transmission.

5. The air-to-ground anti-interference transmission game method based on active intelligent metasurfaces according to claim 1, characterized in that, The upper-level optimization problem in the game model is constructed and solved with the goal of maximizing the legitimate utility function, resulting in a secure transmission strategy for the legitimate system, specifically: fixed ,optimization Introducing auxiliary variables The original problem is transformed into a convex optimization problem, which is then solved using the CVX toolkit. Then by Solve Thus, the power allocation for legitimate transmission is obtained; fixed ,optimization The original objective function is transformed into a problem of generalized Rayleigh entropy and generalized eigenvalues, which is then solved to obtain... ; fixed ,optimization ; derived from the maximum ratio transmission (MRT) theory ; fixed ,optimization ; By integrating the various sub-problems into a BCD framework, the overall optimization of the original problem is achieved, resulting in the optimal strategy for active metasurface-assisted secure transport. The overall optimization of the original problem is as follows: in, For a valid utility function, Let be the legal transmit power for the (t-1)th iteration. Let be the transmit beamforming vector for the (t-1)th iteration. Let be the received beamforming vector for the (t-1)th iteration. Let be the diagonal phase shift matrix of ARIS in the (t-1)th iteration. Let be the legal transmit power for the t-th iteration. Let be the transmit beamforming vector for the t-th iteration. Let be the received beamforming vector for the t-th iteration. Let be the diagonal phase shift matrix of ARIS in the t-th iteration.

6. The air-to-ground anti-interference transmission game method based on active intelligent metasurfaces according to claim 5, characterized in that, Maximizing the utility function of a legal system: in, Let D be the received beamforming vector. The transmit beamforming vector at the transmitting end. For legal transmission power, This is the diagonal phase shift matrix of ARIS. For a valid utility function, This is the conjugate transpose of the received beamforming vector at receiver D. For an equivalent channel from a legitimate sender S to a receiver D, This is the equivalent channel from the interferer J to the receiver D. Let J be the transmitted beamforming vector of the interferator. This represents the background noise at ARIS. This is the channel from RIS to receiver D. The background noise at receiver D. The cost coefficient in the legal utility function, The maximum power limit for legal launch, For the channel from the legitimate sender S to ARIS, For the channel from the interferer J to ARIS, Due to the maximum power limit of ARIS, This is the maximum amplification limit of ARIS. The set of natural numbers, For the optimal transmit beamforming vector of the interferator J, For optimal interference power, This is the interference utility function.

7. A space-to-ground anti-interference transmission game system based on an active intelligent metasurface, characterized in that, include: The scenario module constructs a communication scenario including an intelligent jammer, a legitimate user, an active RIS (Real-Intrusion Response System), and a drone-based aerial base station. In this scenario, the number of antennas for the legitimate sender S, receiver D, and jammer J are N, respectively. S N D N J In this scenario, the legitimate signal is transmitted by a drone airborne base station at a fixed location, and an ARIS with N reflective elements is deployed to assist the system in resisting interference and thus maximize the reception effect. The channels from legitimate sender S to ARIS, from legitimate sender S to receiver D, from interferer J to ARIS, from interferer J to receiver D, and from ARIS to receiver D are as follows: , , , , ,in, The symbol for the complex field. The number of reflective elements, The legal number of transmitting antennas, This refers to the number of antennas at the receiving end. The number of antennas at the interfering transmitter; The diagonal phase shift matrix of ARIS is: , , ,in, , This is a transpose operation; The function module determines the received signal at the receiver and the signal-to-dryness ratio expression; a game model based on Stackelberg game theory is constructed to obtain the utility function of the interfering party and the utility function of the legitimate system; The received signal and the received signal-to-dryness ratio at receiver D are respectively: in, Let D be the received beamforming vector. , These are the transmitted signals from the transmitting end and the jamming point, respectively. , These are the transmit beamforming vectors at the transmitting end and the interference point, respectively. , Let ARIS and receiver D represent the background noise vectors, respectively. This is the conjugate transpose of the received beamforming vector at receiver D. The signal vector received by the receiver. For an equivalent channel from a legitimate sender S to a receiver D, This is the equivalent channel from the interferer J to the receiver D. This is the channel from RIS to receiver D. To interfere with transmission power, For legal transmission power, This is the diagonal phase shift matrix of ARIS. This represents the background noise at ARIS. The background noise at receiver D; The utility functions of the disruptor and the legal system are as follows: in, The cost coefficient in the legal utility function; The cost coefficient in the interference utility function. Let D be the received beamforming vector. , These are the transmit beamforming vectors at the transmitting end and the interference point, respectively. For a valid utility function, Let be the interference utility function. For legal transmission power, To interfere with transmission power, This is the diagonal phase shift matrix of ARIS. For the received signal drying ratio; The interference module constructs and solves the lower-level optimization problem in the game model based on the obtained interference utility function, with the goal of maximizing the interference utility function, to obtain the interference strategy of the interference machine. The transmission module constructs and solves the upper-level optimization problem in the game model based on the obtained legal system utility function, with the goal of maximizing the legal utility function, to obtain the secure transmission strategy of the legal system.

Images