Interference efficiency evaluation method independent of direct information feedback

Abstract

The invention provides an interference efficiency evaluation method independent of direct information feedback, and relates to the field of wireless communication security. In the face of unknown communication modes and channel power gain conditions, the cognitive jammer measures the advantages and disadvantages of different interference decisions through interference effect evaluation, and the interference decisions are optimized or adjusted. Before evaluation, the cognitive jammer firstly analyzes a cognitive communication interference effect evaluation model, working protocols of the cognitive jammer and a communication pair and characteristics of different communication power control models. During evaluation, the cognitive jammer recognizes the communication power control model through regular multi-node cooperative interference induction, and then locates the hidden terminal. On the basis of communication pair node positions, communication and interference channel power gains are estimated, so that interference effect function values of the cognitive jammer under different interference decisions are obtained. According to the method, the interference effect evaluation under the non-cooperative condition is realized, a basis is provided for cognitive interference decision optimization, and the cognitive interference efficiency is improved.

Description

Technical Field

[0001] The present application relates to the field of wireless communication security technology, and in particular to an interference effectiveness evaluation method that does not rely on direct information feedback. Background Art

[0002] In cognitive jamming, jamming effect evaluation is an indispensable part of decision adjustment and optimization. However, in practice, since the communication party and the jammer are usually in a non-cooperative relationship, it is difficult for the cognitive jammer to directly obtain feedback on various state parameters of the communication party, making it very difficult to evaluate the jamming effect. When being interfered with, the communication party may usually adopt a power domain adjustment strategy to offset or adapt to the interference, and its strategy model and parameter information are unknown to the jammer.

[0003] As for the evaluation of interference effects, the current work can be divided into three categories according to different evaluation angles: evaluation based on the communication party, evaluation based on a third party, and evaluation based on the interference party. The first type of work focuses on evaluating the impact of external interference on the communication system itself, in order to provide support for the optimal anti-interference decision. Its characteristic is that the communication party can usually obtain various communication status information feedback from the receiving party before and after the interference. The second type of work mainly evaluates the interference effectiveness of different interference decisions for different communication systems from a third-party perspective, which can provide an optimization basis for interference and anti-interference decisions at the same time. It can usually obtain accurate information about both the interference and the interfered parties, and can make accurate evaluations. The third type of work mainly evaluates the degree of interference of the communication party from the perspective of the interference party, and uses the evaluation results as the premise for optimizing its own interference decision. This work usually requires evaluating the interference effect by sensing the changes in the state parameters of the communication party before and after the interference. However, at this time, it may be difficult for the interference party to directly obtain the state information about the communication party before and after the interference, especially when the two parties are in a non-cooperative relationship. For example, in cognitive jamming or cognitive electronic warfare applications, jammers can usually only rely on partial prior knowledge and real-time perception to evaluate the jamming effect on the communication system. Therefore, for a certain communication system, how to conduct accurate and efficient jamming effectiveness evaluation from the perspective of the jammer is an issue worthy of attention and research.

[0004] As for the signal-to-interference-noise ratio related evaluation indicators, the performance evaluation involves the unknown link channel power gain, the unknown communication pair power control model and parameters. When faced with the challenges of lack of prior information, non-cooperative communication pairs and unlabeled data, optimization methods and machine learning methods may be difficult to directly and accurately solve the problem effectively. Summary of the invention

[0005] The present application provides an interference effectiveness evaluation method that does not rely on direct information feedback, and can be used to solve the technical problem that optimization methods and machine learning methods are difficult to directly, accurately and effectively solve the problem when faced with challenges such as lack of prior information, non-cooperative communication and unlabeled data.

[0006] The present application provides a method for evaluating interference effectiveness without relying on direct information feedback, the method comprising the following steps:

[0007] The present application provides a method for evaluating interference effectiveness without relying on direct information feedback, the method comprising the following steps:

[0008] Step 1: Cognitive jammer j initializes the maximum jamming power p of each jamming node j,max , the number of power equal division intervals Δ, the interference induction period M, the noise power coefficient η and the constant R, generate four interference transmitting node locations (x l ,y l ),l=1,2,3,4, obtain the communication pair transmitter position (x a ,y a );

[0009] Step 2: For each interfering transmitting node l, l = 1, 2, 3, 4, first induce interference for M cycles, and in each cycle m = 1, 2, ..., M, use the power set The interference signal is transmitted in ascending order, and the communication pair transmission power of the corresponding time slot is recorded, so as to obtain the communication pair transmission power sequence O a ; According to the relationship between the transmission power of the communication pair and the interference power of different interference nodes of the jammer, the matrix is ​​obtained After performing density-based clustering on the matrix element points, the power relationship vector is obtained Then, according to a preset first judgment criterion, a power control model of the communication pair is identified;

[0010] Step 3: For the interfering transmitting node l, l = 1, 2, 3, 4, and Obtain the corresponding communication pair power control model parameters and calculate the distance ratio from each interference transmitting node to the hidden communication receiver Then, the position trajectory equation of the hidden communication receiver is obtained from the distance relationship, and the position (x, y) of the hidden communication receiver is solved;

[0011] Step 4: According to the communication receiver position (x, y) obtained, the power gain h of each link channel is obtained. a and

[0012] Step 5: According to the constant R, power relationship Each link channel power gain ha and Output interference effect evaluation function value

[0013] Further, step 1 comprises:

[0014] A jamming system including a single-antenna cognitive jammer and a single-antenna communication pair is defined, wherein the cognitive jammer includes a sensing node and a jamming transmitting node;

[0015] For a communication pair, the positions of the communication sender a and the receiver b are q a =(x a ,y a ) and q b =(x b ,y b ), and dynamically adjust the transmission power according to the channel conditions and the interference size during information transmission; for the cognitive jammer, it can autonomously complete the perception, communication interference decision-making and effect evaluation process based on the OODA loop according to the task requirements, and the positions of the interference transmission node j and the perception node s are q j =(x j ,y j ) and q s =(x s ,y s ); In addition, the transmission power of the communication transmitting end and the jammer transmitting node are expressed as p a ,0≤p a ≤p a,max and p j ,0≤p j ≤p j,max ;

[0016] Considering the free space path loss model, the channel power gains between the communication transmitter and the receiver, between the communication transmitter and the jammer sensing node, and between the jammer transmitting node and the communication receiver are expressed as h a,b 、h a,s and h j,b , which is expressed as follows:

[0017]

[0018]

[0019] Among them, β0 represents the channel power gain when the reference distance is 1m; according to the above analysis, the signal to interference plus noise ratio (SINR) of the communication receiving end for the communication signal is:

[0020]

[0021] Among them, σ 2 Represents the Gaussian white noise power; similarly, the signal-to-noise ratio (SNR) of the jammer sensing node to the communication signal is:

[0022]

[0023] in, represents the Gaussian white noise power;

[0024] The transmission frame protocol of the communication pair is defined as follows: Each communication frame consists of T transmission time slots, and each communication time slot consists of the following three stages: The first stage is the decision stage, in which the communication initiator decides the transmission power of this time slot based on its own power control strategy and feedback; the second stage is the transmission stage, in which the communication initiator transmits data at a fixed power; the third stage is the feedback stage, in which the communication receiver transmits ACK, NACK and other messages through the control link to provide the initiator with link information related to this time slot;

[0025] The definition of the jammer working time slot includes three stages: the first stage is the perception stage, in which the jammer perception node deployed near the communication source continuously perceives the transmission power of the communication source; the second stage is the decision stage, in which the jammer combines the perception information and the evaluation results to intelligently decide the transmission power of the interference signal in this time slot; the third stage is the interference stage, in which the jammer transmitting node implements interference according to the transmission power decided in the previous stage; only the power control strategy / power anti-interference behavior of the communication pair is considered, that is, the occupied frequency does not change during the communication process, so the jammer only perceives the transmission power of the communication source in the perception stage; in addition, since the feedback and decision stages of the communication time slot are shorter than the transmission stage, they can be ignored for simplicity. Similarly, the perception and decision stages of the interference time slot are also ignored. Therefore, assuming that the interference time slot and the communication time slot are synchronized, the data transmission time is approximately equal to the interference signal transmission time; in addition, considering that the communication channel occupancy may be discontinuous, it is assumed that the communication user restarts channel training and makes access decisions in the first time slot of each frame, that is, in terms of power decision, the first transmission time slot of each frame is independent of the last time slot of the previous frame;

[0026] When the external environment changes, the communication pair will adopt a certain power control strategy to adapt to or resist this change. For the jammer, in order to achieve the jamming effect evaluation, it is very important to obtain the power control strategy of the communication pair. Therefore, the following will introduce several common communication power control models including:

[0027] TCI model: In some applications, the communication pair needs to ensure that the signal-to-interference-to-noise ratio of its communication link remains unchanged, that is, to maintain the quality of service (QoS) of the communication link, and the TCI (Truncated channel inversion) model is one of the famous models. In the TCI model, the transmission power of the communication pair is expressed as follows:

[0028]

[0029] in, represents the given target signal-to-interference-noise ratio value, α=h a,b / (h j,b p j +σ 2 ), α Th It is the threshold that determines whether communication transmission is interrupted;

[0030] WF model: Contrary to the previous idea, when the value of α becomes smaller, the communication pair may choose to save power to wait for a better transmission opportunity, that is, the transmission power The value of increases with the increase of α, and vice versa. One of the typical models is called WF (Water-filling), and the transmit power of the communicable pair is expressed as follows:

[0031]

[0032] Where μ is a constant and α = h a,b / (h j,b p j +σ 2 ), whose value is related to the average transmission power;

[0033] Greedy model: In this model, the cognitive communication pair will decide the optimal transmission power in each communication time slot to maximize its own utility function. In the power domain, a commonly used utility function is the weighted sum of the signal-to-interference-noise ratio of the communication link and the transmission power cost. For this utility model, the communication pair power control behavior is expressed as follows:

[0034]

[0035] Where U(·) represents the utility function of the communication pair, c represents the constant coefficient, σ 2 represents the Gaussian white noise power, h a,b and h j,b They represent the channel power gains between the communication transmitting end and the receiving end, and between the jammer transmitting node and the communication receiving end respectively;

[0036] ε-Greedy Model: This model is an improvement of the greedy model. It is a strategy that cognitive communication pairs usually adopt to balance exploration and utilization. Its core idea is to make random decisions with a probability of ε in each decision time slot, and to make greedy optimal decisions with a probability of 1-ε. Based on this, the power control behavior of the communication pair is expressed as follows:

[0037]

[0038] in, p a ′ represents a random power value in the communication pair power set, h a,b and h j,b They represent the channel power gain between the communication transmitting end and the receiving end, and between the jammer transmitting node and the communication receiving end respectively; according to the analysis, when the environment (mainly refers to p j and h j,b ) changes, the transmission power changes of the communication pair will also satisfy certain rules, and these rules may be exploited by jammers with perception capabilities.

[0039] Therefore, the present invention uses the signal interference noise ratio reduction of the communication pair as an indicator to measure the interference effect; the signal interference noise ratio reduction function of the communication pair in the kth communication frame with a frame length of T in the tth time slot is defined as follows:

[0040] Φ(k,t)=R-γ b (k,t) (10)

[0041] Where R is a constant, γ b (k, t) represents the signal-to-interference-noise ratio value of the communication pair in the tth time slot of the kth communication frame; the cognitive jammer needs to evaluate the γ b The estimated value of (k,t) And expect the error between them The smaller the better;

[0042] Let the power value of the communication user in the tth time slot of the kth communication frame be p a (k, t), correspondingly, the interference power of the jammer in this time slot is p j (k, t); In the first time slot of each frame, since the communication pair transmits without channel training / sensing, it is impossible to predict whether interference exists; therefore, when the communication pair adopts the TCI power control strategy, the transmission power of the communication pair is as follows:

[0043]

[0044] Among them, σ 2 represents the Gaussian white noise power, represents the given target signal-to-interference-noise ratio value, h arepresents the channel power gain between the communication transmitting end and the receiving end; however, considering that interference is actually possible, the actual signal-to-interference-to-noise ratio of the communication pair in the current time slot is:

[0045]

[0046] Among them, σ 2 represents the Gaussian white noise power, represents the given target signal-to-interference-noise ratio value, h a It represents the channel power gain between the communication transmitting end and the receiving end, h j represents the channel power gain between the jammer transmitting node and the communication receiving end; in the feedback and decision stage of the current time slot, the user transmitting end decides the transmission power of the access channel in the next time slot according to the signal interference and noise ratio of this time slot; therefore, the power of the communication pair in the second time slot of the current frame is:

[0047]

[0048] Among them, σ 2 represents the Gaussian white noise power, represents the given target signal-to-interference-noise ratio value, h a It represents the channel power gain between the communication transmitting end and the receiving end, h j represents the channel power gain between the jammer transmitting node and the communication receiving end; at this time, considering that the interference is less than the threshold, the actual signal to noise ratio of the communication pair in the second time slot is:

[0049]

[0050] Among them, σ 2 represents the Gaussian white noise power, represents the given target signal-to-interference-noise ratio value, h a It represents the channel power gain between the communication transmitting end and the receiving end, h j represents the channel power gain between the jammer transmitting node and the communication receiving end; by analogy, the signal-to-interference-noise ratio of the communication pair in time slot t, t∈[2,T] is:

[0051]

[0052] Among them, σ 2 represents the Gaussian white noise power, represents the given target signal-to-interference-noise ratio value, h j represents the channel power gain between the jammer transmitting node and the communication receiving end; at this time, the corresponding communication pair transmission power is:

[0053]

[0054] Among them, σ 2represents the Gaussian white noise power, represents the given target signal-to-interference-noise ratio value, h a It represents the channel power gain between the communication transmitting end and the receiving end, h j It represents the channel power gain between the jammer transmitting node and the communication receiving end;

[0055] Simplifying equation (15), there is a linear positive correlation between the transmission power of the communication pair at time slot t and the interference power at time slot t-1, that is, the following relationship holds:

[0056] p a (k,t)=b·p j (k,t-1)+d (17)

[0057] in, σ 2 represents the Gaussian white noise power, represents the given target signal-to-interference-noise ratio value, h a It represents the channel power gain between the communication transmitting end and the receiving end, h j It represents the channel power gain between the jammer transmitting node and the communication receiving end;

[0058] When the communication user adopts the WF power control model, the transmission power of the communication pair decreases as the communication environment deteriorates; similarly, in the first time slot of each frame, the communication pair transmits without channel training / sensing, that is, without considering the interference situation, and the transmission power is as follows:

[0059]

[0060] Among them, σ 2 represents the Gaussian white noise power, μ is a constant related to the average transmission power, and h a It represents the channel power gain between the communication transmitting end and the receiving end. Considering the interference, the signal-to-interference-to-noise ratio of the communication pair in this time slot is:

[0061]

[0062] Among them, σ 2 represents the Gaussian white noise power, μ is a constant related to the average transmission power, and h a It represents the channel power gain between the communication transmitting end and the receiving end, h j represents the channel power gain between the jammer transmitting node and the communication receiving end; after feedback adjustment, the transmission power of the communication pair in the second time slot of each frame is:

[0063]

[0064] Among them, σ 2represents the Gaussian white noise power, μ is a constant related to the average transmission power, and h j represents the channel power gain between the jammer transmitting node and the communication receiving end; considering the existence of interference, the signal-to-interference-to-noise ratio of the communication pair in the second time slot is:

[0065]

[0066] Among them, σ 2 represents the Gaussian white noise power, μ is a constant related to the average transmission power, and h a It represents the channel power gain between the communication transmitting end and the receiving end, h j represents the channel power gain between the jammer transmitting node and the communication receiving end; by analogy, the signal-to-interference-noise ratio of the communication pair in time slot t, t∈[2,T] is:

[0067]

[0068] Among them, σ 2 represents the Gaussian white noise power, μ is a constant related to the average transmission power, and h a It represents the channel power gain between the communication transmitting end and the receiving end, h j represents the channel power gain between the jammer transmitting node and the communication receiving end; at this time, the corresponding communication pair transmission power is:

[0069]

[0070] Among them, σ 2 represents the Gaussian white noise power, μ is a constant related to the average transmission power, and h a It represents the channel power gain between the communication transmitting end and the receiving end, h j It represents the channel power gain between the jammer transmitting node and the communication receiving end;

[0071] Simplifying formula (23), we can get that there is a linear negative correlation between the transmission power of the communication pair at time slot t and the interference power at time slot t-1, that is, the following relationship holds:

[0072] p a (k,t)=b′·p j (k,t-1)+d′ (24)

[0073] in, σ 2 represents the Gaussian white noise power, μ is a constant related to the average transmission power, and h a It represents the channel power gain between the communication transmitting end and the receiving end, h j It represents the channel power gain between the jammer transmitting node and the communication receiving end;

[0074] When the communication pair adopts a greedy transmission strategy, the transmission power in the first time slot of each frame is as follows:

[0075]

[0076] After feedback, the transmission power of the communication pair in time slot t, t∈[2,T] is:

[0077]

[0078] Among them, p a ′ is the random power value, p a,max is the maximum transmit power of the communication pair;

[0079] When the channel power gain remains unchanged, h a,b / (p j (k,t-1)·h j,b +σ 2 )-c is a j (k, t-1); when the interference power gradually increases, the transmission power of the communication pair suddenly changes to 0. At this time, the interference power is the cutoff power, and its value is p j,cut-off =(h a,b / c-σ 2 ) / h j,b ;

[0080] When the communication pair adopts the ε-greedy transmission model, the transmission power in the first time slot of each frame is as follows:

[0081]

[0082] Then, the transmission power of the communication pair in time slot t, t∈[2,T] is:

[0083]

[0084] Among them, p a ′ is the random power value, p a,max is the maximum transmit power of the communication pair;

[0085] Similarly, we can obtain the relationship between the transmission power of the communication pair in time slot t and the interference power in time slot t-1; through the above analysis, we can observe and analyze the relationship between the transmission power and interference power of the communication pair to classify the power control model of the communication pair.

[0086] Furthermore, step 2 includes:

[0087] In the case of interference induction, the jammer power is set to be discrete, that is:

[0088]

[0089] Where Δ is the number of equally divided intervals, p j,max is the maximum transmit power of the jammer, p j (k, t0 represents the interference power of the jammer in the tth time slot of the kth frame; let the interference induction period be M, M<T. In each period, the jammer transmitting node transmits signals in the order of power from small to large, so as to obtain the power sequence O of the communication transmitting end. a ={p i,n |i∈[1,M],n∈[1,Δ]}, where This results in the following power relationship matrix:

[0090]

[0091] The matrix elements correspond to the points in the power relationship diagram. After density-based clustering, the matrix By vector It is expressed as follows:

[0092]

[0093] Where Δ is the number of equally divided intervals, p j,max is the maximum transmission power of the jammer; according to the first judgment criterion, the matrix and vector Determining a power control model of a communication pair;

[0094] The first judgment criterion process is as follows:

[0095] The first step is to determine the matrix Are all the columns of the same? If so, execute the second step, otherwise it is determined to be an ε-greedy model;

[0096] Step 2: Observe the vector The first few groups of elements n<<Δ, if the interference power is positively correlated with the transmit power of the communication pair, it is determined to be a TCI model, if it is negatively correlated, it is determined to be a WF model, if the transmit power of the communication pair is constant, it is determined to be a greedy model.

[0097] Further, step 3 includes:

[0098] Analyze the specific power control model and get the expressions of hidden receiver position under different models;

[0099] TCI model: When the transmission power of the communication pair in time slot t is related to the interference power in time slot t-1, and When the representation is known, the coefficients b and d in the linear positive correlation between the communication pair transmission power at time slot t and the interference power at time slot t-1 in equation (17) can be determined; the h between different interference nodes and the communication receiver j,b is different, and the signal-to-interference-to-noise ratio target of the communication pair is and h a is constant; therefore, considering the line-of-sight link model, the channel power gain from the four interfering nodes to the communication receiver is and The following relations are satisfied:

[0100]

[0101] Among them, κ l , l = 1, 2, 3, 4 are obtained from the slopes of the curves of the relationship between the transmission power of the communication pair and the interference power of the four interference nodes; the ratio of the distances from the four interference nodes to the communication receiving end is:

[0102]

[0103] Let the positions of the four interference nodes be (x1, y1), (x2, y2), (x3, y3) and (x4, y4), and the position of the communication receiving end be (x, y); the coordinate position trajectory of the receiver that satisfies the ratio of the distance to the jammers j1 and j2 satisfies:

[0104]

[0105] Simplifying formula (34) yields:

[0106]

[0107] According to formula (35), when κ1≠κ2, the receiver position trajectory is a circle; and when κ1≠κ2, the trajectory is a straight line, which is the perpendicular bisector between the two jammer position points;

[0108] Similarly, the position point trajectory satisfying the other two sets of relations is obtained, and the position of the hidden communication receiver is obtained by the intersection of the trajectory;

[0109] WF model: Based on the above analysis, the coefficients b′, d′ in equation (24) are easy to obtain; therefore, the channel power gain from the four interfering nodes to the communication receiver is and The following relations are satisfied:

[0110]

[0111] Among them, κ l, l = 1, 2, 3, 4 is obtained from the slope of the curve of the relationship between the transmission power of the communication pair and the interference power between the four interference nodes; Similar to the discussion under the TCI model, the communication receiver position coordinates also satisfy:

[0112]

[0113] After obtaining the other two sets of trajectory relationships, the communication receiver position *x,y(is determined;

[0114] Consider the greedy model: let p j,max >p j,cut-off According to the above analysis, the cut-off power p j,cut-off =(h a,b / c-σ 2 ) / h j,b ; The cutoff power values ​​corresponding to the four known interfering nodes After that, due to h a,b ,c,σ 2 The same for different interference nodes, the channel power gain from the four interference nodes to the communication receiver is and The relationship between them is shown as follows:

[0115]

[0116] have to:

[0117]

[0118] After obtaining the relationship shown in equation (39), the conclusions about the first two models can be used to determine the communication receiver position (x, y);

[0119] The communication receiver positioning process under the ε-greedy model is the same as that of the greedy model, which will not be repeated here. It should be noted that when there is an error in the estimated value of the distance ratio, it will affect the solution of the equation system, so a communication receiver position with a certain error from the actual position will be obtained.

[0120] Further, step 4 includes:

[0121] After obtaining the hidden communication receiver position (x, y), the jammer can estimate the channel power gain between each jammer node and the communication receiver, and between the communication transmitter and the receiver. and h a , which is expressed as follows:

[0122]

[0123] Among them, (x a ,y a ) represents the communication transmitter location, represents the position of the lth jammer, and β0 represents the channel power gain when the reference distance is 1m. Since the communication transmitter continuously sends signals, its position is easy to determine and can be regarded as a known quantity.

[0124] Further, step 5 comprises:

[0125] In getting h a and After that, the signal to interference noise ratio decrease function of the kth frame tth time slot of the communication pair is estimated as:

[0126]

[0127] Among them, R is the set constant, h a It represents the channel power gain between the communication transmitting end and the receiving end. represents the channel power gain between the jammer transmitting node l and the communication receiving end, σ 2 is the white noise power, p a (k,t) is the transmission power of the communication pair in the tth time slot of the kth frame, represents the transmission power of the jammer transmitting node l; in equation (41), only the communication link noise power σ 2 is unknown, however, it is related to the power of the interference at the receiving end Compared with , it can usually be ignored, but for more rigorousness, the present invention estimates the noise power as:

[0128]

[0129] Where η is the noise power factor, represents the channel power gain between the jammer transmitting node l and the communication receiving end, represents the transmission power of the jammer transmitting node l; so far, the cognitive jammer obtains the jamming effectiveness of different time slots.

[0130] The effects of this application include:

[0131] 1. The present invention proposes a method for evaluating the interference effect of the interference party based on cooperative interference induction. In the proposed evaluation method, the cognitive jammer deploys multiple interference nodes to regularly transmit interference power, obtains the relationship between the interference power of different interference nodes and the communication power, and thus derives the power control model, position and channel-related information of the communication receiver, thereby realizing the interference effect evaluation without direct information feedback. Compared with no evaluation, the proposed evaluation method provides support for cognitive interference decision optimization and improves the interference efficiency.

[0132] 2. The present invention utilizes the idea of ​​cognitive interference effectiveness evaluation to solve the problem of interference effectiveness evaluation under conditions of incomplete information by enhancing perception through interference, designs highly universal evaluation criteria and evaluation indicators, and enables the cognitive interference function to evaluate in real time and optimize its own interference decision.

[0133] 3. The present invention proposes the idea of ​​cognitive interference effectiveness evaluation and an interference effect evaluation method for the interferer based on collaborative interference induction. It can accurately and in real time estimate the interference effectiveness for communication users adopting a power domain control model through reasonable interference node positions and interference power set settings, and has great application potential in actual physical layer security and cognitive confrontation. BRIEF DESCRIPTION OF THE DRAWINGS

[0134] Figure 1 It is a model diagram of the interference system in the present invention.

[0135] Figure 2 It is a model diagram of the working protocol of the cognitive jammer and the communication pair in the present invention.

[0136] Figure 3 This is a multi-node collaborative interference induction model diagram in the present invention.

[0137] Figure 4 It is a work flow chart of the interference effect evaluation method of the present invention.

[0138] Figure 5 It is a comparison diagram of the average utility of the interference effect evaluation method of the present invention and other methods when the constant coefficient θ changes.

[0139] Figure 6 It is the relationship between the relative error of the signal to interference noise ratio estimation of the interference effect evaluation method of the present invention and the noise power coefficient η under different power control models.

[0140] Figure 7 It is the relationship between the relative error of the signal to interference noise ratio estimation of the interference effect evaluation method of the present invention and the power step length ρ under the greedy model and the ε greedy model respectively. DETAILED DESCRIPTION

[0141] In order to make the objectives, technical solutions and advantages of the present application clearer, the implementation methods of the present application will be further described in detail below with reference to the accompanying drawings.

[0142] The following first introduces the embodiments of the present application in conjunction with the accompanying drawings.

[0143] The cognitive jammer first analyzes the cognitive communication interference effect evaluation model, the working protocol of the cognitive jammer and the communication pair, and the characteristics of different communication power control models, and designs evaluation criteria and evaluation indicators. During the evaluation, the cognitive jammer uses the idea of ​​cognitive interference effectiveness evaluation to identify the communication power control model through regular multi-node cooperative interference induction, and then locates the hidden terminal. Based on the position of the communication pair nodes, the power gain of the communication and interference channels is estimated, so as to obtain the interference effect function value of the cognitive jammer under different interference decisions, and realize real-time and accurate evaluation of interference effectiveness without direct information feedback.

[0144] like Figure 1 As shown in Figure 1, the jamming system consists of a single-antenna cognitive jammer and a single-antenna communication pair, where the cognitive jammer consists of a sensing node and a jamming transmitting node. For the communication pair, the positions of the communication transmitter (a) and the receiver (b) are q a =(x a ,y a ) and q b =(x b ,y b ), and it will dynamically adjust the transmission power according to the channel conditions and the interference size during information transmission; for the cognitive jammer, it can autonomously complete the perception, communication interference decision-making and effect evaluation process based on the OODA loop according to the task requirements, and the positions of the interference transmission node (j) and the perception node (s) are q j =(x j ,y j ) and q s =(x s ,y s ). In addition, the transmission power of the communication transmitting end and the jammer transmitting node can be expressed as p a ,0≤p a ≤p a,max and p j ,0≤p j ≤p j,max .

[0145] Considering the free space path loss model, the channel power gains between the communication transmitter and the receiver, between the communication transmitter and the jammer sensing node, and between the jammer transmitting node and the communication receiver can be expressed as h a,b 、h a,s and h j,b , which can be expressed as follows

[0146]

[0147] Among them, β0 represents the channel power gain when the reference distance is 1m. According to the above analysis, the signal to interference plus noise ratio (SINR) of the communication receiving end for the communication signal is

[0148]

[0149] Among them, σ 2 Represents the Gaussian white noise power. Similarly, the signal-to-noise ratio (SNR) of the jammer sensing node to the communication signal is

[0150]

[0151] in, represents the Gaussian white noise power.

[0152] like Figure 2 As shown in the figure, the working frame protocol of the cognitive jammer and the communication pair is as follows: Each communication frame consists of T transmission time slots, and each communication time slot consists of the following three stages: 1) Decision stage, the communication transmitter decides the transmission power of this time slot according to its own power control strategy and feedback; 2) Transmission stage, the communication transmitter transmits data at a fixed power; 3) Feedback stage, the communication receiver will return ACK, NACK and other messages through the control link to provide the transmitter with link information related to this time slot; The jammer working time slot consists of three stages: 1) Perception stage, the jammer perception node deployed near the communication transmitter continuously perceives the transmission power of the communication transmitter; 2) Decision stage, the jammer combines the perception information and evaluation results to intelligently decide the transmission power of the interference signal in this time slot; 3) Interference stage, the jammer transmitting node implements interference according to the transmission power decided in the previous stage. Here, only the power control strategy / power anti-interference behavior of the communication pair is considered, that is, the occupied frequency does not change during the communication process, so the jammer only needs to perceive the transmission power of the communication transmitter in the perception stage. In addition, since the feedback and decision phase of the communication time slot is shorter than the transmission phase, it can be ignored for simplicity. Similarly, the perception and decision phase of the interference time slot is also ignored. Therefore, assuming that the interference time slot and the communication time slot are synchronized, the data transmission time is approximately equal to the interference signal transmission time. In addition, considering that the communication channel occupancy may be discontinuous, it is assumed that the communication user restarts channel training and makes access decisions in the first time slot of each frame, that is, in terms of power decision, the first transmission time slot of each frame is independent of the last time slot of the previous frame.

[0153] Below Figure 3 As an example, the multi-jammer cooperative interference induction-positioning process is specifically described. Let the power value of the communication user in the tth time slot of the kth communication frame be pa (k, t), correspondingly, the interference power of the jammer in this time slot is p j (k, t). Through interference induction, the relationship between the transmission power of the communication pair in time slot t and the interference power of different interference nodes in time slot t-1 can be obtained. For example, for the TCI model, the following relationship holds

[0154] p a (k,t)=b·p j (k,t-1)+d (6)

[0155] in,

[0156] When the communication user adopts the WF power control model, the following relationship holds

[0157] p a (k,t)=b′·p j (k,t-1)+d′ (7)

[0158] in,

[0159] When the communication pair adopts a greedy transmission strategy, its transmission power in the first time slot of each frame is as follows:

[0160]

[0161] After feedback, the transmission power of the communication pair in time slot t, t∈[2,T] is

[0162]

[0163] Among them, p a ′ is a random power value.

[0164] When the communication pair adopts the ε-greedy transmission model, its transmission power in the first time slot of each frame is as follows:

[0165]

[0166] Then, the transmission power of the communication pair in time slot t, t∈[2,T] is

[0167]

[0168] In the case of interference induction, the jammer power is set to be discrete, that is,

[0169]

[0170] Where Δ is the number of equally divided intervals, Let the interference induction period be M, M<T. In each period, the jammer transmitting node transmits signals in the order of power from small to large, so as to obtain the power sequence O of the communication transmitting end. a ={p i,n |i∈[1,M],n∈[1,Δ]}, where From this we can get the following power relationship matrix

[0171]

[0172] After density-based clustering of the matrix elements (corresponding to the points in the power relationship diagram), the matrix Vector It indicates that the details are as follows

[0173]

[0174] According to criterion 1, the matrix and vector The power control model of the communication pair can be determined.

[0175] First judgment criterion: 1) The first step is to judge the matrix Are all the columns of the same? If so, jump to the second step, otherwise it is determined to be an ε-greedy model; 2) In the second step, observe the vector For the first few groups of elements (n<<Δ), if the interference power is positively correlated with the transmission power of the communication pair, it is determined to be a TCI model; if it is negatively correlated, it is determined to be a WF model; if the transmission power of the communication pair is constant, it is determined to be a greedy model.

[0176] Analyze the specific power control model and obtain the ratio of the distances from the four interfering nodes to the communication receiving end. Then the trajectory equation that the hidden receiver position should satisfy is derived, thereby obtaining the hidden receiver position expressions under different models.

[0177] The present invention adopts Figure 4 The process shown includes the following steps:

[0178] Step 1: Cognitive jammer j initializes the maximum jamming power p of each jamming node j,max , the number of power equal division intervals Δ, the interference induction period M, the noise power coefficient η and the constant R, generate four interference transmitting node locations (x l ,y l ),l=1,2,3,4, obtain the communication pair transmitter position (x a ,y a ), go to step 2;

[0179] Step 2: For each interfering transmitting node l (l = 1, 2, 3, 4), first induce interference for M cycles, and in each cycle m = 1, 2, ..., M, use the power set The interference signal is transmitted in ascending order, and the communication pair transmission power of the corresponding time slot is recorded, so as to obtain the communication pair transmission power sequence O a ; According to the relationship between the transmission power of the communication pair and the interference power of different interference nodes of the jammer, the matrix is ​​obtained After performing density-based clustering on the matrix element points, the power relationship vector is obtained Then, according to the first judgment criterion, the power control model of the communication pair is identified, and step 3 is executed;

[0180] Step 3: For the interfering transmitting node l, l = 1, 2, 3, 4, and The corresponding communication pair power control model parameters are obtained, and further, the distance ratio of each interference transmitting node to the hidden communication receiver is calculated. Then, the position point trajectory equation of the hidden communication receiver is obtained from the distance relationship, and the position (x, y) of the hidden communication receiver is solved, and step 4 is executed;

[0181] Step 4: Based on the communication receiver position (x, y) obtained, the power gain h of each link channel can be obtained: a and Go to step 5.

[0182] Step 5: According to the constant R, power relationship Each link channel power gain h a and Output interference effect evaluation function value

[0183] The present invention will be further described below in conjunction with specific embodiments.

[0184] The effectiveness of the present invention is verified by simulation examples. First, the scenario setting of the embodiment is briefly introduced. Consider a jamming system consisting of a cognitive jammer and a communication pair, where the cognitive jammer consists of a sensing node and four transmitting nodes. The network size is 400mx400m, and the positions of all nodes are randomly generated. The channel power gain at the reference distance is β0=-30dB. The noise spectrum density is -100dBm. The maximum interference power and communication transmission power are 20W and 2W respectively. The induced interference power step size p j,max / Δ=0.05W, interference induction period M=20, noise power coefficient η=0.01, constant C=1. In terms of communication power control model parameters, α Th= 0.1, μ = 3, c = 0.5 and ε = 0.01. For the transmission frame protocol, the frame length is T = 1000. Without loss of generality, for 3×10 4 The experimental data were averaged to obtain the results.

[0185] Then, three interference decision methods were run using the Matlab simulation platform: ① Greedy decision enabled by the proposed evaluation method: In each decision time slot, the cognitive jammer greedily selects actions (i.e., interference power size) according to its own utility value, and its utility is defined as the weighted sum of the negative value of the communication party's signal-to-interference-noise ratio and its own interference power cost, as shown in the following formula

[0186]

[0187] ② Greedy decision-making enabled by optimal evaluation: The utility function definition and action selection process of the cognitive jammer are the same as the above scheme, but the difference is that it can accurately obtain σ 2 、h a and h j The value of, that is, this decision scheme is a greedy decision enabled by optimal evaluation; ③ Decision without evaluation enablement: In each decision time slot, the jammer cannot obtain the jamming effect evaluation result, and thus cannot measure the quality of the action. It can only Randomly select actions from .

[0188] The relevant comparison results are as follows Figure 5 As shown, it can be found that the effect achieved by the effect evaluation method based on collaborative interference induction proposed in the present invention is second only to the optimal evaluation, and compared with the effect achieved without evaluation, the average utility can be improved by more than 60%.

[0189] Figure 5 is the average utility of different schemes when the constant coefficient θ changes. Among them, the decision time slot length T = 200, and the constant coefficient changes in the range of [0.01, 0.1]. Analysis of this figure shows that the average utility of the algorithm proposed in the present invention is close to the optimal evaluation algorithm. At the same time, as the constant coefficient increases, the average utility of the proposed algorithm shows a downward trend.

[0190] Figure 6 is the relative error level of the signal to interference noise ratio estimation when the noise power coefficient changes. The relative error is defined as follows

[0191]

[0192] Analysis of this figure shows that under different power control models, as the noise coefficient increases, the relative error of the signal to interference and noise ratio estimation of the proposed algorithm increases, but the absolute value remains at a low level (less than 5%).

[0193] Figure 7is the relative error level of the SINR estimation when the power step size changes. From the analysis of this figure, we can see that with the increase of the power step size ρ, the relative error of the SINR estimation shows an exponential upward trend.

[0194] Table 1 shows the relative error level of the signal to noise ratio estimation when the time offset ratio changes. It can be seen from the table that when the time offset ratio is 10 -9 When the signal to interference and noise ratio estimation error level is low (no more than 4%).

[0195] Table 1: Relative error level of SIR estimation when the time offset ratio changes

[0196]

[0197] The present invention has been described above in an illustrative manner using embodiments. Those skilled in the art should understand that the present disclosure is not limited to the embodiments described above, and that various changes, modifications and substitutions may be made without departing from the scope of the present invention, and that the parts not covered by the present invention are the same as the prior art or may be implemented using the prior art.

[0198] The above-described embodiments of the present application do not constitute a limitation on the protection scope of the present application.

Claims

1. A method for evaluating interference effectiveness without relying on direct information feedback, characterized in that: The method comprises the following steps: Step 1: Cognitive jammer j initializes the maximum jamming power p of each jamming node j，max , the number of power equal division intervals Δ, the interference induction period M, the noise power coefficient η and the constant R, generate four interference transmitting node locations (x l ,y l ), l = 1, 2, 3, 4, obtain the communication pair transmitter position (x a ,y a ); Step 2: For each interfering transmitting node l, l = 1, 2, 3, 4, first induce interference for M cycles, and in each cycle m = 1, 2, ..., M, use the power set The interference signal is transmitted in ascending order, and the communication pair transmission power of the corresponding time slot is recorded, so as to obtain the communication pair transmission power sequence O a ; According to the relationship between the transmission power of the communication pair and the interference power of different interference nodes of the jammer, the matrix is ​​obtained After performing density-based clustering on the matrix element points, the power relationship vector is obtained Then, according to a preset first judgment criterion, a power control model of the communication pair is identified; Step 3: For the interfering transmitting node l, l = 1, 2, 3, 4, and Obtain the corresponding communication pair power control model parameters and calculate the distance ratio from each interference transmitting node to the hidden communication receiver Then, the position trajectory equation of the hidden communication receiver is obtained from the distance relationship, and the position (x, y) of the hidden communication receiver is solved; Step 4: According to the communication receiver position (x, y) obtained, the channel power gain ha and Step 5: According to the constant R, power relationship Each link channel power gain h a and Output interference effect evaluation function value 2. The interference effectiveness evaluation method according to claim 1 that does not rely on direct information feedback is characterized in that: Step 1 includes: A jamming system including a single-antenna cognitive jammer and a single-antenna communication pair is defined, wherein the cognitive jammer includes a sensing node and a jamming transmitting node; For a communication pair, the positions of the communication sender a and the receiver b are q a =(x a ,y a ) and q b =(x b ,y b ), and dynamically adjust the transmission power according to the channel conditions and the interference size during information transmission; for the cognitive jammer, it can autonomously complete the perception, communication interference decision-making and effect evaluation process based on the OODA loop according to the task requirements, and the positions of the interference transmission node j and the perception node s are q j =(x j ,y j ) and q s =(x s ,y s ); In addition, the transmission power of the communication transmitting end and the jammer transmitting node are expressed as p a , 0≤p a ≤p a，max and p j , 0≤p j ≤p j，max ; Considering the free space path loss model, the channel power gains between the communication transmitter and the receiver, between the communication transmitter and the jammer sensing node, and between the jammer transmitting node and the communication receiver are expressed as h a，b 、h a，s and h j，b , which is expressed as follows: Among them, β0 represents the channel power gain when the reference distance is 1m; the signal-to-interference-noise ratio of the communication signal at the communication receiving end is: Among them, σ 2 represents the Gaussian white noise power; the signal-to-noise ratio of the jammer sensing node to the communication signal is: in, represents the Gaussian white noise power; The transmission frame protocol of the communication pair is defined as follows: Each communication frame consists of T transmission time slots, and each communication time slot consists of the following three stages: The first stage is the decision stage, in which the communication initiator decides the transmission power of this time slot based on its own power control strategy and feedback; the second stage is the transmission stage, in which the communication initiator transmits data at a fixed power; the third stage is the feedback stage, in which the communication receiver transmits ACK, NACK and other messages through the control link to provide the initiator with link information related to this time slot; The definition of the jammer working time slot includes three stages: the first stage is the perception stage, in which the jammer perception node deployed near the communication source continuously perceives the transmission power of the communication source; the second stage is the decision stage, in which the jammer combines the perception information and the evaluation results to intelligently decide the interference signal transmission power of this time slot; the third stage is the interference stage, in which the jammer transmitting node implements interference according to the transmission power decided in the previous stage; only the power control strategy / power anti-interference behavior of the communication pair is considered, that is, the occupied frequency does not change during the communication process, so the jammer only perceives the transmission power of the communication source in the perception stage; assuming that the interference time slot and the communication time slot are synchronized, the data transmission time is equal to the interference signal transmission time; assuming that the communication user restarts channel training and makes access decisions in the first time slot of each frame, that is, in terms of power decision, the first transmission time slot of each frame is independent of the last time slot of the previous frame; The communication power control model includes: TCI model: The transmit power of a communication pair is expressed as follows: in, represents the given target signal-to-interference-noise ratio value, α=h a,b / (h j,b p j +σ 2 ), α Th It is the threshold that determines whether communication transmission is interrupted; WF model: The transmit power of a communication pair is expressed as follows: Where μ is a constant and α = h a,b / (h j,b p j +σ 2 ), whose value is related to the average transmission power; Greedy model: The communication pair power control behavior is expressed as follows: Where U(·) represents the utility function of the communication pair, c represents the constant coefficient, σ 2 represents the Gaussian white noise power, h a,b and h j,b They represent the channel power gains between the communication transmitting end and the receiving end, and between the jammer transmitting node and the communication receiving end respectively; ε-greedy model: The communication pair power control behavior is expressed as follows: in, p′ a represents a random power value in the communication pair power set, h a,b and h j,b They represent the channel power gains between the communication transmitting end and the receiving end, and between the jammer transmitting node and the communication receiving end respectively; The signal interference noise ratio reduction of the communication pair is used as an indicator to measure the interference effect. The signal interference noise ratio reduction function of the communication pair in the kth communication frame with a frame length of T in the tth time slot is defined as follows: Φ(k,t)=R-γ b (k,t) (10) Where R is a constant, γ b (k, t) represents the signal-to-interference-noise ratio value of the communication pair in the tth time slot of the kth communication frame; the cognitive jammer needs to evaluate the γ b The estimated value of (k,t) And expect the error between them The smaller the better; Let the power value of the communication user in the tth time slot of the kth communication frame be p a (k, t), correspondingly, the interference power of the jammer in this time slot is p j (k, t); In the first time slot of each frame, since the communication pair transmits without channel training / sensing, it is impossible to predict whether interference exists; therefore, when the communication pair adopts the TCI power control strategy, the transmission power of the communication pair is as follows: Among them, σ 2 represents the Gaussian white noise power, represents the given target signal-to-interference-noise ratio value, h a represents the channel power gain between the communication transmitting end and the receiving end; however, considering that interference is actually possible, the actual signal-to-interference-to-noise ratio of the communication pair in the current time slot is: Among them, σ 2 represents the Gaussian white noise power, represents the given target signal-to-interference-noise ratio value, h a It represents the channel power gain between the communication transmitting end and the receiving end, h j represents the channel power gain between the jammer transmitting node and the communication receiving end; in the feedback and decision stage of the current time slot, the user transmitting end decides the transmission power of the access channel in the next time slot according to the signal interference and noise ratio of this time slot; therefore, the power of the communication pair in the second time slot of the current frame is: Among them, σ 2 represents the Gaussian white noise power, represents the given target signal-to-interference-noise ratio value, h a It represents the channel power gain between the communication transmitting end and the receiving end, h j represents the channel power gain between the jammer transmitting node and the communication receiving end; at this time, considering that the interference is less than the threshold, the actual signal to noise ratio of the communication pair in the second time slot is: Among them, σ 2 represents the Gaussian white noise power, represents the given target signal-to-interference-noise ratio value, h a It represents the channel power gain between the communication transmitting end and the receiving end, h j represents the channel power gain between the jammer transmitting node and the communication receiving end; the signal-to-interference-noise ratio of the communication pair in time slot t, t∈[2,T] is: Among them, σ 2 represents the Gaussian white noise power, represents the given target signal-to-interference-noise ratio value, h j represents the channel power gain between the jammer transmitting node and the communication receiving end; at this time, the corresponding communication pair transmission power is: Among them, σ 2 represents the Gaussian white noise power, represents the given target signal-to-interference-noise ratio value, h a It represents the channel power gain between the communication transmitting end and the receiving end, h j It represents the channel power gain between the jammer transmitting node and the communication receiving end; Simplifying equation (15), there is a linear positive correlation between the transmission power of the communication pair at time slot t and the interference power at time slot t-1, that is, the following relationship holds: p a (k,t)=b·p j (k,t-1)+d (17) in, σ 2 represents the Gaussian white noise power, represents the given target signal-to-interference-noise ratio value, h a It represents the channel power gain between the communication transmitting end and the receiving end, h j It represents the channel power gain between the jammer transmitting node and the communication receiving end; When the communication user adopts the WF power control model, the transmission power of the communication pair decreases as the communication environment deteriorates; in the first time slot of each frame, the communication pair transmits without channel training / sensing, that is, without considering the interference situation, and the transmission power is as follows: Among them, σ 2 represents the Gaussian white noise power, μ is a constant related to the average transmission power, and h a It represents the channel power gain between the communication transmitting end and the receiving end. Considering the interference, the signal-to-interference-to-noise ratio of the communication pair in this time slot is: Among them, σ 2 represents the Gaussian white noise power, μ is a constant related to the average transmission power, and h a It represents the channel power gain between the communication transmitting end and the receiving end, h j represents the channel power gain between the jammer transmitting node and the communication receiving end; after feedback adjustment, the transmission power of the communication pair in the second time slot of each frame is: Among them, σ 2 represents the Gaussian white noise power, μ is a constant related to the average transmission power, and h j represents the channel power gain between the jammer transmitting node and the communication receiving end; considering the existence of interference, the signal-to-interference-to-noise ratio of the communication pair in the second time slot is: Among them, σ 2 represents the Gaussian white noise power, μ is a constant related to the average transmission power, and h a It represents the channel power gain between the communication transmitting end and the receiving end, h j represents the channel power gain between the jammer transmitting node and the communication receiving end; the signal-to-interference-noise ratio of the communication pair in time slot t, t∈[2,T] is: Among them, σ 2 represents the Gaussian white noise power, μ is a constant related to the average transmission power, and h a It represents the channel power gain between the communication transmitting end and the receiving end, h j represents the channel power gain between the jammer transmitting node and the communication receiving end; at this time, the corresponding communication pair transmission power is: Among them, σ 2 represents the Gaussian white noise power, μ is a constant related to the average transmission power, and h a It represents the channel power gain between the communication transmitting end and the receiving end, h j It represents the channel power gain between the jammer transmitting node and the communication receiving end; Simplifying formula (23), we can get that there is a linear negative correlation between the transmission power of the communication pair at time slot t and the interference power at time slot t-1, that is, the following relationship holds: p a (k,t)=b′·p j (k,t-1)+d′ (24) in, σ 2 represents the Gaussian white noise power, μ is a constant related to the average transmission power, and h a It represents the channel power gain between the communication transmitting end and the receiving end, h j It represents the channel power gain between the jammer transmitting node and the communication receiving end; When the communication pair adopts a greedy transmission strategy, the transmission power in the first time slot of each frame is as follows: After feedback, the transmission power of the communication pair in time slot t, t∈[2,T] is: Among them, p′ a is the random power value, p a,max is the maximum transmit power of the communication pair; When the channel power gain remains unchanged, h a,b / (p j (k,t-1)·h j,b +σ 2 )-c is a j (k, t-1); when the interference power gradually increases, the transmission power of the communication pair suddenly changes to 0. At this time, the interference power is the cutoff power, and its value is p j,cut-off =(h a,b / c-σ 2 ) / h j,b ; When the communication pair adopts the ε-greedy transmission model, the transmission power in the first time slot of each frame is as follows: Then, the transmission power of the communication pair in time slot t, t∈[2,T] is: Among them, p′ a is the random power value, p a,max is the maximum transmit power of the communication pair; Similarly, we can obtain the relationship between the transmission power of the communication pair in time slot t and the interference power in time slot t-1; observe and analyze the relationship between the transmission power and interference power of the communication pair to classify the power control model of the communication pair.

3. The interference effectiveness evaluation method according to claim 2 that does not rely on direct information feedback is characterized in that: Step 2 includes: In the case of interference induction, the jammer power is set to be discrete, that is: Where Δ is the number of equally divided intervals, p j,max is the maximum transmit power of the jammer, p j (k, t) represents the interference power of the jammer in the tth time slot of the kth frame; let the interference induction period be M, M<T, in each period, the jammer transmitting node transmits signals in the order of power from small to large, so as to obtain the power sequence O of the communication transmitting end a ={p i,n |i∈[1,M],n∈[1,Δ]}, where This results in the following power relationship matrix: The matrix elements correspond to the points in the power relationship diagram. After density-based clustering, the matrix By vector It is expressed as follows: Where Δ is the number of equally divided intervals, p j,max is the maximum transmission power of the jammer; according to the first judgment criterion, the matrix and vector Determining a power control model of a communication pair; The first judgment criterion process is as follows: The first step is to determine the matrix Are all the columns of the same? If so, execute the second step, otherwise it is determined to be an ε-greedy model; Step 2: Observe the vector The first few groups of elements n<<Δ, if the interference power is positively correlated with the transmit power of the communication pair, it is determined to be a TCI model, if it is negatively correlated, it is determined to be a WF model, if the transmit power of the communication pair is constant, it is determined to be a greedy model.

4. The interference effectiveness evaluation method according to claim 3 that does not rely on direct information feedback is characterized in that: Step 3 includes: Analyze the specific power control model and get the expressions of hidden receiver position under different models; TCI model: When the transmission power of the communication pair in time slot t is related to the interference power in time slot t-1, and When the representation is known, the coefficients b and d in the linear positive correlation between the communication pair transmission power at time slot t and the interference power at time slot t-1 in equation (17) can be determined; the h between different interference nodes and the communication receiver j,b is different, and the signal-to-interference-to-noise ratio target of the communication pair is and h a is constant; therefore, considering the line-of-sight link model, the channel power gain from the four interfering nodes to the communication receiver is and The following relations are satisfied: Among them, κ l , l = 1, 2, 3, 4 are obtained from the slopes of the curves of the relationship between the transmission power of the communication pair and the interference power of the four interference nodes; the ratio of the distances from the four interference nodes to the communication receiving end is: Let the positions of the four interference nodes be (x1, y1), (x2, y2), (x3, y3) and (x4, y4), and the position of the communication receiving end be (x, y); the coordinate position trajectory of the receiver that satisfies the ratio of the distance to the jammers j1 and j2 satisfies: Simplifying formula (34), we get: According to formula (35), when κ1≠κ2, the receiver position trajectory is a circle; and when κ1≠κ2, the trajectory is a straight line, which is the perpendicular bisector between the two jammer position points; Obtain the position point trajectory that satisfies the other two sets of relationships, and the hidden communication receiver position is obtained by the intersection of the trajectory; WF model: The coefficients b′, d′ in equation (24) are easy to obtain; therefore, the channel power gain from the four interfering nodes to the communication receiver is and The following relations are satisfied: Among them, κ l , l = 1, 2, 3, 4 is obtained from the slope of the curve of the relationship between the transmission power of the communication pair and the interference power of the four interference nodes; the position coordinates of the communication receiver also satisfy: After obtaining the other two sets of trajectory relationships, the communication receiver position (x, y) is determined; Consider the greedy model: let p j,max >p j,cut-off , cut-off power p j,cut-off =(h a,b / c-σ 2 ) / h j,b ; The cutoff power values ​​corresponding to the four known interfering nodes After that, due to h a,b ,c,σ 2 The same for different interference nodes, the channel power gain from the four interference nodes to the communication receiver is and The relationship between them is shown as follows: have to: After obtaining the relationship shown in formula (39), the communication receiver position *x,y(; The communication receiver positioning process under the ε-greedy model is the same as that under the greedy model.

5. The interference effectiveness evaluation method according to claim 4 that does not rely on direct information feedback is characterized in that: Step 4 includes: After obtaining the hidden communication receiver position (x, y), the jammer can estimate the channel power gain h between each jammer node and the communication receiver, and between the communication transmitter and the receiver. jl ,l=1,2,3,4 and h a , which is expressed as follows: Among them, (x a ,y a ) represents the communication transmitter location, represents the position of the lth jammer, and β0 represents the channel power gain when the reference distance is 1m.

6. The interference effectiveness evaluation method according to claim 5 that does not rely on direct information feedback, characterized in that: Step 5 includes: In getting h a and After that, the signal to interference noise ratio decrease function of the kth frame tth time slot of the communication pair is estimated as: Among them, R is the set constant, h a It represents the channel power gain between the communication transmitting end and the receiving end. represents the channel power gain between the jammer transmitting node l and the communication receiving end, σ 2 is the white noise power, p a (k,t) is the transmission power of the communication pair in the tth time slot of the kth frame, represents the transmission power of the jammer transmitting node l; in equation (41), only the communication link noise power σ 2 is unknown, the noise power is estimated as: Where η is the noise power factor, represents the channel power gain between the jammer transmitting node l and the communication receiving end, represents the transmission power of the jammer transmitting node l; so far, the cognitive jammer obtains the jamming effectiveness of different time slots.

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