A method for evaluating interference performance without relying on direct information feedback

Abstract

This application provides a method for evaluating interference effectiveness without relying on direct information feedback, relating to the field of wireless communication security. When faced with unknown communication modes and channel power gain conditions, a cognitive jammer evaluates the interference effectiveness to assess the merits of different interference decisions, optimizing or adjusting these decisions. Before evaluation, the cognitive jammer first analyzes the cognitive communication interference effectiveness evaluation model, the working protocols of the cognitive jammer and the communication pair, and the characteristics of different communication power control models. During evaluation, the cognitive jammer identifies the communication power control model through regular multi-node cooperative interference induction, and then locates the hidden terminal. Based on the node positions of the communication pair, the power gain of the communication and interference channels is estimated, thereby obtaining the interference effectiveness function values ​​of the cognitive jammer under different interference decisions. This invention achieves interference effectiveness evaluation under non-cooperative conditions, providing a basis for cognitive interference decision optimization and improving cognitive interference effectiveness.

Description

Technical Field

[0001] This application relates to the field of wireless communication security technology, and in particular to a method for evaluating interference effectiveness that does not rely on direct information feedback. Background Technology

[0002] In cognitive interference, interference effect assessment is an indispensable part of decision adjustment and optimization. However, in practice, because the communicating party and the interfering party are usually non-cooperative, cognitive jammers have difficulty directly obtaining feedback on various state parameters of the communicating party, making interference effect assessment extremely difficult. When subjected to interference, the communicating party may usually adopt some kind of power domain adjustment strategy to counteract or adapt to the interference, and its strategy model and parameter information are unknown to the jammer.

[0003] Regarding interference effect assessment, current work can be broadly categorized into three types based on the assessment perspective: assessment based on the communicating party, assessment based on a third party, and assessment based on the interfering party. The first type focuses on assessing the impact of external interference on the communication system itself, aiming to support optimal anti-interference decisions. Its characteristic is that the communicating party typically receives feedback from the receiver regarding various communication state information before and after interference. The second type primarily assesses the interference effectiveness of different interference decisions for different communication systems from a third-party perspective. This can provide optimization basis for both interference and anti-interference decisions, typically obtaining precise information from both the interfering and affected parties, enabling accurate assessment. The third type primarily assesses the effectiveness of the interference from the interfering party's perspective, using the assessment results as a prerequisite for optimizing its own interference decisions. This work usually requires assessing the interference effect by sensing changes in the communicating party's state parameters before and after interference. However, in this case, the interfering party may find it difficult to directly obtain information about the communicating party's state before and after interference, especially when the two parties are not in a cooperative relationship. For example, in cognitive jamming or cognitive electronic warfare applications, jammers typically rely only on partial prior knowledge and real-time perception to assess the jamming effect on their own communication systems. Therefore, how to conduct accurate and efficient jamming effectiveness assessments from the jammer's perspective for a specific communication system is a problem worthy of attention and research.

[0004] Regarding signal-to-interference-plus-noise ratio (SIR) related evaluation metrics, performance assessment involves issues such as unknown link channel power gain and unknown communication power control models and parameters. Furthermore, when faced with challenges such as lack of prior information, non-cooperative communication, and unlabeled data, optimization and machine learning methods may struggle to directly and accurately solve these problems. Summary of the Invention

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

[0006] This application provides a method for evaluating interference effectiveness that does not rely on direct information feedback. The method includes the following steps:

[0007] This application provides a method for evaluating interference effectiveness that does not rely on direct information feedback. The method includes the following steps:

[0008] Step 1: Initialize the maximum interference power p of each interference node in the cognitive jammer j. j,max The four interference transmitting node positions (x, y, y) are generated by considering the power division interval Δ, interference induced period M, noise power figure η, and constant R. l ,y l ), l=1,2,3,4, obtain the transmitter position (x) of the communication pair. a ,y a );

[0009] Step 2: For each interfering transmitting node l, l = 1, 2, 3, 4, first induce interference for M cycles. Within each cycle m = 1, 2, ..., M, use power concentration... Interference signals are transmitted in ascending order, and the transmission power of the communication pair in the corresponding time slot is recorded, thus obtaining the transmission power sequence O of the communication pair. a The matrix is ​​obtained based on the relationship between the transmission power of the communication device and the jamming power of different jamming nodes of the jammer. After performing density-based clustering on the matrix elements, a power relationship vector is obtained. Then, based on the preset first judgment criterion, the power control model of the communication pair is identified;

[0010] Step 3: For the interfering transmitting nodes l, l = 1, 2, 3, 4, from and The corresponding communication pair power control model parameters are obtained, and the distance ratio from each interfering transmitting node to the hidden communication receiver is calculated. Then, the trajectory equation of the hidden communication receiver's location point is derived from the distance relationship, and the location (x, y) of the hidden communication receiver is solved.

[0011] Step 4: Based on the obtained communication receiver position (x, y), obtain the channel power gain h for each link. a and

[0012] Step 5: Based on the constant R and power relationship, Power gain h of each link channela and Output interference effect evaluation function value

[0013] Further, step 1 includes:

[0014] Define a jamming system comprising a single-antenna cognitive jammer and a single-antenna communication pair, wherein the cognitive jammer includes a sensing node and a jamming transmitting node;

[0015] For a communication pair, the positions of the transmitting end a and the receiving end b are q respectively. a =(x a ,y a ) and q b =(x b ,y b Furthermore, during information transmission, the transmission power is dynamically adjusted based on channel conditions and the magnitude of interference. For cognitive jammers, the process of sensing, communication interference decision-making, and effect evaluation based on the OODA loop can be completed autonomously according to task requirements, and the positions of the jamming transmitting node j and the sensing node s are q respectively. j =(x j ,y j ) and q s =(x s ,y s Furthermore, the transmit power of the communication transmitter and the jammer transmitter node are respectively 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 receiver, between the communication transmitter and the jammer sensing node, and between the jammer transmitting node and the communication receiver are respectively expressed as h. a,b h a,s and h j,b , means as follows:

[0017]

[0018]

[0019]

[0020] Where β0 represents the channel power gain at a reference distance of 1m; based on the above analysis, the signal-to-interference-plus-noise ratio (SINR) of the communication receiver for the communication signal is:

[0021]

[0022] Where, σ 2 This represents the power of Gaussian white noise; similarly, the signal-to-noise ratio (SNR) of the jammer's sensing node for the communication signal is:

[0023]

[0024] in, Indicates the power of Gaussian white noise;

[0025] The transmission frame protocol for 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, where the transmitting end decides the transmission power of this time slot based on its own power control strategy and feedback; the second stage is the transmission stage, where the transmitting end transmits data at a fixed power; the third stage is the feedback stage, where the receiving end sends back ACK, NACK, and other messages through the control link, providing the transmitting end with link information related to this time slot;

[0026] The jammer's operating time slot is defined as consisting of three stages: the first stage is the sensing stage, where jammer sensing nodes deployed near the communication transmitter continuously sense the transmission power of the transmitter; the second stage is the decision stage, where the jammer intelligently decides the jamming signal transmission power for this time slot based on the sensed information and evaluation results; the third stage is the jamming stage, where the jammer transmitting nodes implement jamming based on the transmission power decided in the previous stage. Only the power control strategy / power anti-jamming behavior of the communication pair is considered, i.e., the occupied frequency does not change during communication. Therefore, the jammer only senses the transmission power of the communication transmitter during the sensing stage. Furthermore, 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 sensing and decision stages of the jamming time slot are also ignored. Therefore, assuming that the jamming time slot and the communication time slot are synchronized, the data transmission time is approximately equal to the jamming signal transmission time. In addition, considering the possibility of discontinuous communication channel occupancy, 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.

[0027] When the external environment changes, communication pairs will adopt certain power control strategies to adapt to or resist these changes. For jammers, obtaining the power control strategies of communication pairs is crucial for evaluating jamming effectiveness. Therefore, the following will introduce several common communication power control models:

[0028] TCI Model: In some applications, communication pairs need to maintain a constant signal-to-interference-plus-noise ratio (SIR) for their communication links, i.e., maintain the Quality of Service (QoS). The TCI (Truncated Channel Inversion) model is a well-known example of this. In the TCI model, the transmit power of the communication pair is represented as follows:

[0029]

[0030] in, Let α = h represent the given target signal-to-interference-plus-noise ratio. a,b / (h j,b p j +σ 2 ), α Th It is the threshold that determines whether communication transmission is interrupted;

[0031] WF model: Contrary to the previous approach, as the value of α decreases, the communication pair may choose to conserve power to wait for a better transmission opportunity, i.e., transmit power. The value of increases as α increases, and vice versa. One typical model is called WF (Water-filling), whose transmit power for communication pairs is expressed as follows:

[0032]

[0033] Where μ is a constant, α = h a,b / (h j,b p j +σ 2 Its value is related to the average transmission power;

[0034] Greedy Model: In this model, cognitively capable communication pairs decide on the optimal transmission power in each communication time slot to maximize their utility function. In the power domain, a commonly used utility function is the weighted sum of the signal-to-interference-plus-noise ratio (SNR) of the communication link and the transmission power cost. For this utility model, the power control behavior of the communication pairs is represented as follows:

[0035]

[0036] Where U(·) represents the utility function of the communication pair, c represents the constant coefficient, and σ 2 h represents the power of Gaussian white noise. a,b and h j,b These represent the channel power gain between the communication transmitter and receiver, and between the jammer transmitter node and the communication receiver, respectively.

[0037] ε-Greedy Model: This model is an improvement on the greedy model and is a strategy commonly adopted by cognitive communication pairs to balance exploration and exploitation. Its core idea is to make random decisions with probability ε in each decision slot, while performing a greedy optimal decision with probability 1-ε. Based on this, the communication's power control behavior is represented as follows:

[0038]

[0039]

[0040] in, p′ a h represents a random power value in the power set of the communication pair. a,b and h j,b These represent the channel power gains between the transmitting and receiving ends, and between the jammer transmitting node and the receiving end, respectively. Analysis shows that when the environment (mainly referring to p...) j and h j,b When the power of a communication pair changes, the transmission power of the communication pair will also change according to certain rules, and these rules may be exploited by jammers with sensing capabilities.

[0041] Therefore, this invention uses the signal-to-interference-plus-noise ratio (SIR) decrease of the communication pair as an indicator of the effectiveness of the interference; the SIR decrease function of the communication pair in the k-th communication frame and the t-th time slot of frame length T is defined as follows:

[0042] Φ(k,t)=R-γ b (k,t) (10)

[0043] Where R is a constant, γ b (k,t) represents the signal-to-interference-plus-noise ratio (SIR) of the communication pair in the t-th time slot of the k-th communication frame; the cognitive jammer needs to evaluate the SIR of γ. b The estimated value of (k,t) And expect the error between them The smaller the better;

[0044] Let the power value of the communication user in the t-th time slot of the k-th communication frame be p. a (k,t), correspondingly, the jamming 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 / awareness, the presence of interference cannot be predicted; therefore, when the communication pair adopts the TCI power control strategy, the transmission power of the communication pair is as follows:

[0045]

[0046] Where, σ 2 This represents the power of Gaussian white noise. h represents the given target signal-to-interference-plus-noise ratio (SIN / N). a This represents the channel power gain between the transmitting and receiving ends; however, considering that interference is probabilistic and actually exists, the actual signal-to-interference-plus-noise ratio (SIR) of the communication pair in the current time slot is:

[0047]

[0048] Where, σ 2 This represents the power of Gaussian white noise. h represents the given target signal-to-interference-plus-noise ratio (SIN / N). a h represents the channel power gain between the transmitting and receiving ends of a communication connection. j This represents the channel power gain between the jammer transmitting node and the communication receiving end; during the feedback and decision-making phase of the current time slot, the user transmitting end determines the transmit power of the channel to be accessed in the next time slot based on the signal-to-interference-plus-noise ratio of this time slot; therefore, the power of the communication pair in the second time slot of the current frame is:

[0049]

[0050] Where, σ 2 This represents the power of Gaussian white noise. h represents the given target signal-to-interference-plus-noise ratio (SIN / N). a h represents the channel power gain between the transmitting and receiving ends of a communication connection. j This represents the channel power gain between the jammer transmitting node and the communication receiving end; at this time, considering the interference situation is less than the threshold, the actual signal-to-interference-plus-noise ratio (SIR) of the communication pair in the second time slot is:

[0051]

[0052] Where, σ 2 This represents the power of Gaussian white noise. h represents the given target signal-to-interference-plus-noise ratio (SIN / N). a h represents the channel power gain between the transmitting and receiving ends of a communication connection. j This represents the channel power gain between the jammer transmitting node and the communication receiving end; similarly, the signal-to-interference-plus-noise ratio (SINNR) of the communication pair in time slot t, t∈[2,T] is:

[0053]

[0054] Where, σ 2 This represents the power of Gaussian white noise. h represents the given target signal-to-interference-plus-noise ratio (SIN / N). j This 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:

[0055]

[0056] Where, σ 2 This represents the power of Gaussian white noise. h represents the given target signal-to-interference-plus-noise ratio (SIN / N). a h represents the channel power gain between the transmitting and receiving ends of a communication connection. j This represents the channel power gain between the jammer's transmitting node and the communication receiving end;

[0057] Simplified equation (15) shows that there is a linear positive correlation between the transmission power of the communication signal in time slot t and the interference power in time slot t-1, i.e., the following relationship holds:

[0058] p a (k,t)=b·p j (k,t-1)+d (17)

[0059] in, σ 2 This represents the power of Gaussian white noise. h represents the given target signal-to-interference-plus-noise ratio (SIN / N). a h represents the channel power gain between the transmitting and receiving ends of a communication connection. j This represents the channel power gain between the jammer's transmitting node and the communication receiving end;

[0060] When communication users adopt the WF power control model, the transmit 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 / awareness, i.e., without considering interference, and the transmit power is as follows:

[0061]

[0062] Where, σ 2 The value represents the Gaussian white noise power, μ is a constant related to the average transmitted power, and h is... a This represents the channel power gain between the transmitting and receiving ends; considering interference, the signal-to-interference-plus-noise ratio (SIR) for the communication pair in this time slot is:

[0063]

[0064] Where, σ 2 The value represents the Gaussian white noise power, μ is a constant related to the average transmitted power, and h is... a h represents the channel power gain between the transmitting and receiving ends of a communication connection. j This 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:

[0065]

[0066] Where, σ 2 The value represents the Gaussian white noise power, μ is a constant related to the average transmitted power, and h is... j This represents the channel power gain between the jammer transmitting node and the communication receiving end; considering the presence of interference, the signal-to-interference-plus-noise ratio (SIR) of the communication pair in the second time slot is:

[0067]

[0068] Where, σ 2 The value represents the Gaussian white noise power, μ is a constant related to the average transmitted power, and h is... a h represents the channel power gain between the transmitting and receiving ends of a communication connection. j This represents the channel power gain between the jammer transmitting node and the communication receiving end; similarly, the signal-to-interference-plus-noise ratio (SINNR) of the communication pair in time slot t, t∈[2,T] is:

[0069]

[0070] Where, σ 2 The value represents the Gaussian white noise power, μ is a constant related to the average transmitted power, and h is... a h represents the channel power gain between the transmitting and receiving ends of a communication connection. j This 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:

[0071]

[0072] Where, σ 2 The value represents the Gaussian white noise power, μ is a constant related to the average transmitted power, and h is... a h represents the channel power gain between the transmitting and receiving ends of a communication connection. j This represents the channel power gain between the jammer's transmitting node and the communication receiving end;

[0073] Simplifying equation (23), we find that there is a linear negative correlation between the transmission power of communication in time slot t and the interference power in time slot t-1, i.e., the following relationship holds:

[0074] p a (k,t)=b′·p j (k,t-1)+d′ (24)

[0075] in, σ 2 The value represents the Gaussian white noise power, μ is a constant related to the average transmitted power, and h is... a h represents the channel power gain between the transmitting and receiving ends of a communication connection. j This represents the channel power gain between the jammer's transmitting node and the communication receiving end;

[0076] When the communication pair adopts a greedy transmission strategy, the transmit power in the first time slot of each frame is as follows:

[0077]

[0078] After feedback, the transmission power of the communication pair in time slot t, t∈[2,T] is:

[0079]

[0080] Where, p′ a It is a random power value, p a,max It is the maximum transmit power of the communication pair;

[0081] With the channel power gain constant, h a,b / (p j (k,t-1)·h j,b +σ 2 -c is a function that is only affected by p j (k,t-1) are the variables affected; as the interference power gradually increases, the transmission power of the communication pair abruptly drops to 0. At this point, the interference power is the cutoff power, with a value of p. j,cut-off =(h a,b / c-σ 2 ) / h j,b ;

[0082] When the communication pair adopts the ε-greedy transmission model, the transmit power in the first time slot of each frame is as follows:

[0083]

[0084] Therefore, the transmission power of the communication pair in time slot t, t∈[2,T] is:

[0085]

[0086] Where, p′ a It is a random power value, p a,max It is the maximum transmit power of the communication pair;

[0087] Similarly, the relationship between the transmit power of the communication pair in time slot t and the interference power in time slot t-1 can be obtained. Through the above analysis, the power control model of the communication pair can be classified by observing and analyzing the relationship between the transmit power and interference power.

[0088] Furthermore, step 2 includes:

[0089] During interference induction, the jammer power is made discrete, i.e.:

[0090]

[0091] Where Δ is the number of equally divided intervals. p j,max This is the maximum transmit power of the jammer, p j (k,t) represents the jamming power of the jammer in the t-th time slot of the k-th frame; let the jamming induction period be M, M<T, and in each period, the jammer transmitting node transmits signals in ascending power order, thereby obtaining the power sequence O of the communication pair's transmitting end. a ={p i,n |i∈[1,M],n∈[1,Δ]}, where This yields the following power relationship matrix:

[0092]

[0093] The matrix elements are mapped to points in the power graph. After density-based clustering, the matrix... From vector It is expressed as follows:

[0094]

[0095] Where Δ is the number of equally divided intervals, p j,max This is the maximum transmit power of the jammer; according to the first judgment criterion, it is determined by the matrix. sum vector Determine the power control model of the communication pair;

[0096] The first judgment criterion process is as follows:

[0097] The first step is to determine the matrix. If all columns are the same, proceed to step two; otherwise, determine it as an ε-greedy model.

[0098] The second step is to observe the vectors. If the first few elements n << Δ, and the interference power is positively correlated with the transmission power of the communication pair, it is determined to be a TCI model; if they are 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.

[0099] Furthermore, step 3 includes:

[0100] Analysis was conducted on specific power control models to obtain expressions for the hidden receiver location under different models;

[0101] TCI Model: The relationship between the transmit power of a communication pair in time slot t and the interference power in time slot t-1 is given by... and When the characteristics are known, the coefficients b and d in equation (17) showing a linear positive correlation between the communication transmit power in time slot t and the interference power in time slot t-1 can be determined; the h between different interference nodes and the communication receiver j,b They are different, and the signal-to-interference-plus-noise ratio target of the communication pair is different. and h a It remains unchanged; therefore, considering the line-of-sight link model, the channel power gain from the four interfering nodes to the communication receiver is constant. and Satisfy the following relations:

[0102]

[0103] Among them, κ l The values ​​l = 1, 2, 3, and 4 are obtained from the slopes of the curves showing the relationship between the transmission power of the communication pair and the interference power between the four interfering nodes; the ratio of the distances from the four interfering nodes to the communication receiver is:

[0104]

[0105] Let the positions of the four interfering nodes be (x1, y1), (x2, y2), (x3, y3), and (x4, y4), and the position of the communication receiver be (x, y). The receiver's coordinate trajectory, satisfying the ratio of its distances to the interfering nodes j1 and j2, satisfies the following:

[0106]

[0107] Simplifying equation (34) yields:

[0108]

[0109] According to equation (35), when κ1≠k2, the receiver position trajectory is a circle; while when k1≠k2, the trajectory is a straight line, namely the perpendicular bisector of the two jammer position points.

[0110] Similarly, the trajectories of the location points that satisfy the other two sets of relationships are obtained, and the intersection of the trajectories reveals the location of the hidden communication receiver.

[0111] WF Model: Based on the above analysis, the coefficients b′ and d′ in equation (24) are easily obtained; therefore, the channel power gain from the four interfering nodes to the communication receiver is... and Satisfy the following relations:

[0112]

[0113] Among them, κ lThe values ​​l = 1, 2, 3, 4 are obtained from the slope of the curve showing the relationship between the transmission power of the communication pair and the interference power between the four interfering nodes; similar to the discussion under the TCI model, the position coordinates of the communication receiver also satisfy:

[0114]

[0115] After obtaining the other two sets of trajectory relationships, the position (x, y) of the communication receiver is determined;

[0116] Consider the greedy model: Let p j,max >p j,cut-off Based on the aforementioned analysis, the cutoff power p j,cut-off =(h a,b / c-σ 2 ) / h j,b Given the cutoff power values ​​corresponding to the four interference nodes. Afterwards, due to h a,b ,c,σ 2 The channel power gain from all four interfering nodes to the communication receiver is the same for all different interfering nodes. and The relationship between them is expressed as follows:

[0117]

[0118] have to:

[0119]

[0120] After obtaining the relationship shown in equation (39), the position (x,y) of the communication receiver can be determined using the conclusions about the first two models;

[0121] The localization process of the communication receiver under the ε-greedy model is the same as that under the greedy model, and will not be described again here. It should be noted that errors in the estimated distance ratio will affect the solution of the equations, resulting in a communication receiver position that deviates somewhat from the true position.

[0122] Furthermore, step 4 includes:

[0123] After obtaining the location (x, y) of the hidden communication receiver, the jammer can estimate the channel power gain between each jamming node and the communication receiver, and between the communication transmitter and the receiver. and h a , means as follows:

[0124]

[0125] Among them, (x a ,y a () indicates the location of the communication transmitter. Let βl represent the position of the l-th jammer, and β0 represent the channel power gain at a reference distance of 1m. Since the communication transmitters continuously emit signals, their positions are easily determined and can be considered known quantities.

[0126] Furthermore, step 5 includes:

[0127] After obtaining h a and Then, the signal-to-interference-plus-noise ratio (SIR) decrease rate function of the k-th frame and t-th time slot of the communication pair is estimated as follows:

[0128]

[0129] Where R is a set constant, h a This represents the channel power gain between the transmitting and receiving ends of the communication. σ represents the channel power gain between the jammer's transmitting node l and the communication receiving end. 2 p is the white noise power. a (k,t) represents the transmission power of the communication pair in the t-th time slot of the k-th frame. Let represent the transmit power of jammer transmitting node l; in equation (41), only the communication link noise power σ is considered. 2 It is unknown, however, its power relative to interference at the receiver. In comparison, it is usually negligible, but for greater rigor, this invention estimates the noise power as follows:

[0130]

[0131] Where η is the noise power coefficient. This represents the channel power gain between the jammer's transmitting node l and the communication receiving end. This indicates the transmit power of the jammer's transmitting node l; thus, the cognitive jammer obtains the jamming effectiveness in different time slots.

[0132] The effects of this application include:

[0133] 1. This invention proposes a method for evaluating the interference effectiveness of a cooperating interference-induced interference mechanism. In this method, a cognitive jammer deploys multiple interference nodes that transmit interference power in a regular pattern to obtain the relationship between the interference power of different interference nodes and the communication power. This allows for the derivation of the power control model, location, and channel-related information of the communication receiver, achieving interference effectiveness evaluation without direct feedback. Compared to no evaluation method, this proposed method provides support for cognitive interference decision optimization and improves interference effectiveness.

[0134] 2. This invention utilizes the concept of cognitive interference effectiveness evaluation to solve the problem of interference effectiveness evaluation under incomplete information conditions by enhancing perception through interference. It designs highly universal evaluation criteria and indicators to enable the cognitive interference mechanism to evaluate and optimize its own interference decisions in real time.

[0135] 3. This invention proposes a cognitive interference effectiveness evaluation concept and a method for evaluating the interference effect of interfering parties based on cooperative interference induction. It can accurately estimate the interference effectiveness in real time for communication users that adopt a power domain control model by setting reasonable interference node locations and interference power sets. It has great application potential in actual physical layer security and cognitive countermeasures. Attached Figure Description

[0136] Figure 1 This is a model diagram of the interference system in this invention.

[0137] Figure 2 This is a diagram of the cognitive jammer and communication pair working protocol model in this invention.

[0138] Figure 3 This is a diagram of the multi-node cooperative interference-induced model in this invention.

[0139] Figure 4 This is a flowchart of the interference effect evaluation method of the present invention.

[0140] Figure 5 This is a comparison chart of the average utility of the interference effect evaluation method of this invention and other methods when the constant coefficient θ changes.

[0141] Figure 6 This relates the relative error of the signal-to-interference-plus-noise ratio estimation in the interference effect evaluation method of this invention to the noise power coefficient η under different power control models.

[0142] Figure 7 This describes the relationship between the relative error of the signal-to-interference-plus-noise ratio estimation in the interference effect evaluation method of this invention and the power step size ρ under the greedy model and the ε-greedy model, respectively. Detailed Implementation

[0143] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0144] The embodiments of this application will now be described in conjunction with the accompanying drawings.

[0145] The cognitive jammer first analyzes the cognitive communication jamming effectiveness evaluation model, the working protocols of the cognitive jammer and the communication pair, and the characteristics of different communication power control models, and designs evaluation criteria and indicators. During evaluation, the cognitive jammer utilizes the cognitive jamming effectiveness evaluation concept to identify the communication power control model through regular multi-node cooperative jamming, and then locates the hidden terminal. Based on the node locations of the communication pair, it estimates the power gain of the communication and jamming channels, thereby deriving the jamming effect function value of the cognitive jammer under different jamming decisions, achieving real-time and accurate evaluation of jamming effectiveness without direct information feedback.

[0146] like Figure 1 As shown, the jamming system consists of a single-antenna cognitive jammer and a single-antenna communication pair. The cognitive jammer comprises a sensing node and a jamming transmitting node. For the communication pair, the positions of the transmitting end (a) and the receiving end (b) are q, respectively. a =(x a ,y a ) and q b =(x b ,y b Furthermore, it dynamically adjusts its transmission power based on channel conditions and interference levels 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 task requirements, and the positions of the jamming transmitting node (j) and the perception node (s) are q respectively. j =(x j ,y j ) and q s =(x s ,y s Furthermore, the transmit power of the communication transmitter and the jammer transmitter node can be expressed as p, respectively. a ,0≤p a ≤p a,max and p j ,0≤p j ≤p j,max .

[0147] Considering the free-space path loss model, the channel power gain between the communication transmitter and 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, respectively. a,b h a,s and h j,b It can be represented as follows:

[0148]

[0149]

[0150]

[0151] Where β0 represents the channel power gain at a reference distance of 1m. Based on the above analysis, the signal-to-interference-plus-noise ratio (SINR) of the communication receiver for the communication signal is:

[0152]

[0153] Where, σ 2 This represents the power of Gaussian white noise. Similarly, the signal-to-noise ratio (SNR) of the jammer's sensing node for the communication signal is...

[0154]

[0155] in, This represents the power of Gaussian white noise.

[0156] like Figure 2 As shown, 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 transmitting end decides the transmission power of this time slot based on its own power control strategy and feedback; 2) Transmission stage: The transmitting end transmits data at a fixed power; 3) Feedback stage: The receiving end sends back ACK, NACK, and other messages through the control link to provide the transmitting end with link information related to this time slot; The jammer's working time slot consists of three stages: 1) Sensing stage: The jammer's sensing nodes deployed near the transmitting end continuously sense the transmission power of the transmitting end; 2) Decision stage: The jammer combines the sensing information and evaluation results to intelligently decide the transmission power of the jamming signal in this time slot; 3) Jamming stage: The jammer's transmitting nodes implement jamming based on the transmission power decided in the previous stage. Here, only the power control strategy / power anti-jamming behavior of the communication pair is considered, that is, the frequency occupied does not change during communication. Therefore, the jammer only needs to sense the transmission power of the transmitting end in the sensing stage. Furthermore, since the feedback and decision-making phases of communication slots are relatively short compared to the transmission phase, they can be neglected for simplicity. Similarly, the sensing and decision-making phases of interference slots are also neglected. Therefore, assuming that interference slots and communication slots are synchronized, the data transmission time is approximately equal to the interference signal transmission time. In addition, considering the possibility of discontinuous communication channel occupancy, it is assumed that communication users restart channel training and make access decisions in the first slot of each frame; that is, in terms of power decision, the first transmission slot of each frame is independent of the last slot of the previous frame.

[0157] The following is based on Figure 3Taking an example, let's illustrate the multi-jammer cooperative interference induction-localization process. Let the power value of the communication user in the t-th time slot of the k-th communication frame be p. a (k,t), correspondingly, the jamming power of the jammer in this time slot is p. j (k,t). Through interference induction, the relationship between the transmit power of the communication pair in time slot t and the interference power of different interfering nodes in time slot t-1 can be obtained. For example, for the TCI model, the following relationship holds.

[0158] p a (k,t)=b·p j (k,t-1)+d (6)

[0159] in,

[0160] When a communication user adopts the WF power control model, the following relationship holds true.

[0161] p a (k,t)=b′·p j (k,t-1)+d′ (7)

[0162] in,

[0163] When the communication pair adopts a greedy transmission strategy, its transmit power in the first time slot of each frame is as follows:

[0164]

[0165] After feedback, the transmission power of the communication pair in time slot t, t∈[2,T] is:

[0166]

[0167] Where, p′ a It is a random power value.

[0168] When the communication pair adopts the ε-greedy transmission model, its transmit power in the first time slot of each frame is as follows:

[0169]

[0170] Therefore, the transmission power of the communication pair in time slot t, t∈[2,T] is:

[0171]

[0172] During interference induction, the jammer power is made discrete, i.e.

[0173]

[0174] Where Δ is the number of equally divided intervals. Let the interference-induced period be M, where M < T. Within each period, the interfering transmitter nodes transmit signals in ascending order of power, so as to obtain the power sequence O of the communication pair's transmitting end. a = {p i,n | i ∈ [1, M], n ∈ [1, Δ]}, where From this, the following power relation pair matrix can be obtained

[0175]

[0176] After clustering the elements of this matrix (corresponding to the points in the power relation graph) based on density, the matrix can be represented by the vector as follows

[0177]

[0178] According to Criterion 1, the power control model of the communication pair can be determined from the matrix and the vector .

[0179] The first judgment criterion: 1) In the first step, first judge whether each column of the matrix is the same. If so, jump to the second step; otherwise, it is determined as the ε-greedy model. 2) In the second step, observe the first few groups of elements (n << Δ) of the vector . If the interference power is positively correlated with the transmitting power of the communication pair, it is determined as the TCI model; if it is negatively correlated, it is determined as the WF model; if the transmitting power of the communication pair is constant, it is determined as the greedy model.

[0180] Analyze the specific power control model to obtain the ratio of the distances from the four interfering nodes to the communication receiving end Then obtain the trajectory equation that the hidden receiver position should satisfy, so as to obtain the expression of the hidden receiver position under different models.

[0181] The present invention adopts the process as shown in Figure 4 and specifically includes the following steps:

[0182] Step 1: The cognitive jammer j initializes the maximum interference power p of each interfering node j,max , the number of power equal division intervals Δ, the interference-induced period M, the noise power coefficient η, and the constant R, generates the positions (x l , y l ) of four interfering transmitter nodes, where l = 1, 2, 3, 4, obtains the position (x a , y a ) of the communication pair's transmitter, and executes Step 2;

[0183] Step 2: For each interfering transmitting node l (l = 1, 2, 3, 4), first induce interference for M cycles. Within each cycle m = 1, 2, ..., M, use power concentration... Interference signals are transmitted in ascending order, and the transmission power of the communication pair in the corresponding time slot is recorded, thus obtaining the transmission power sequence O of the communication pair. a The matrix is ​​obtained based on the relationship between the transmission power of the communication device and the jamming power of different jamming nodes of the jammer. After performing density-based clustering on the matrix elements, a power relationship vector is obtained. Then, based on the first judgment criterion, the power control model of the communication pair is identified, and step 3 is executed;

[0184] Step 3: For the interfering transmitting nodes l, l = 1, 2, 3, 4, from and The corresponding communication pair power control model parameters were obtained, and further, the distance ratio from each interfering transmitting node to the hidden communication receiver was calculated. Then, the trajectory equation of the hidden communication receiver's location point is obtained from the distance relationship, and the location (x, y) of the hidden communication receiver is solved. Then, step 4 is executed.

[0185] Step 4: Based on the obtained communication receiver position (x, y), the channel power gain h of each link can be obtained. a and Perform step 5;

[0186] Step 5: Based on the constant R and power relationship, Power gain h of each link channel a and Output interference effect evaluation function value

[0187] The present invention will be further described below with reference to specific embodiments.

[0188] The effectiveness of this invention is verified through simulation examples below. First, the scenario setup of the embodiment is briefly introduced, considering an interference system consisting of a cognitive jammer and communication pairs. The cognitive jammer comprises one sensing node and four transmitting nodes. The network size is 400m x 400m, and the positions of all nodes are randomly generated. The channel power gain at the reference distance is β0 = -30dB. The noise spectral density is -100dBm. The maximum interference power and communication transmit power are 20W and 2W, respectively. The induced interference power step size p... j,max / Δ=0.05W, interference induced period M=20, noise power figure η=0.01, constant C=1. Regarding the parameters of the communication power control model, α Th=0.1, μ=3, c=0.5 and ε=0.01. For the transmission frame protocol, the frame length T=1000. Without loss of generality, for 3×10 4 The results were obtained by averaging the data from each experiment.

[0189] Then, three interference decision-making methods were run using the Matlab simulation platform: ① Greedy decision-making enabled by the proposed evaluation method: In each decision time slot, the cognitive jammer greedily selects an action (i.e., the magnitude of interference power) based on its own utility value. Its utility is defined as the weighted sum of the negative value of the signal-to-interference-plus-noise ratio of the communication party and its own interference power cost, as shown in the following formula.

[0190]

[0191] ② Greedy decision-making with optimal evaluation enablement: The utility function definition and action selection process of the cognitive interference machine are the same as those of the aforementioned schemes, 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 with optimal evaluation enablement; ③ Decision without evaluation enablement: In each decision time slot, the jammer cannot obtain the evaluation result of the jamming effect, and therefore cannot measure the quality of the action. It can only obtain the value of the power set. Randomly select an action.

[0192] The relevant comparison results are as follows Figure 5 As shown, it can be found that the effect evaluation method based on cooperative interference induction proposed in this invention is second only to the optimal evaluation, and can improve the average utility by more than 60% compared with the effect of no evaluation.

[0193] Figure 5 The figure shows the average utility of different schemes as the constant coefficient θ changes. The decision time slot length T = 200, and the constant coefficient ranges from [0.01, 0.1]. Analysis of this figure shows that the average utility of the proposed algorithm is approximately the same as the optimal evaluation algorithm. Furthermore, the average utility of the proposed algorithm decreases as the constant coefficient increases.

[0194] Figure 6 The relative error level is used to estimate the signal-to-interference-plus-noise ratio (SIR) as the noise power figure changes. The relative error is defined as follows:

[0195]

[0196] Analysis of this figure shows that, under different power control models, as the noise figure increases, the relative error of the proposed algorithm's signal-to-interference-plus-noise ratio estimation increases, but the absolute value remains at a low level (below 5%).

[0197] Figure 7The graph shows the relative error level of the signal-to-interference-plus-noise ratio (SNR) estimation when the power step size changes. Analysis of this graph reveals that the relative error of the SNR estimation increases exponentially with the increase of the power step size ρ.

[0198] Table 1 shows the relative error level of signal-to-interference-plus-noise ratio (SIR) estimation as the time offset ratio changes. The table shows that when the time offset ratio is 10... -9 At this level, the signal-to-interference-plus-noise ratio (SINR) estimation error is low (not exceeding 4%).

[0199] Table 1: Relative Error Levels of Signal-to-Interference-plus-Noise Ratio Estimation When Time Offset Scale Changes

[0200]

[0201] The present invention has been described above by way of examples. Those skilled in the art should understand that this disclosure is not limited to the embodiments described above, and various changes, modifications, and substitutions can be made without departing from the scope of the present invention.

[0202] Furthermore, all parts not covered in this invention are the same as or can be implemented using existing technologies.

[0203] The embodiments described above do not constitute a limitation on the scope of protection of this application.

Claims

1. A method for evaluating interference effectiveness that does not rely on direct information feedback, characterized in that, The method includes the following steps: Step 1: Initialize the maximum interference power p of each interference node in the cognitive jammer j. j,max The four interference transmitting node positions (x, y, y) are generated by considering the power division interval Δ, interference induced period M, noise power figure η, and constant R. l ,y l ), l=1,2,3,4, obtain the transmitter position (x) of the communication pair. a ,y a ); Step 2: For each interfering transmitting node l, l = 1, 2, 3, 4, first induce interference for M cycles. Within each cycle m = 1, 2, ..., M, use power concentration... Interference signals are transmitted in ascending order, and the transmission power of the communication pair in the corresponding time slot is recorded, thus obtaining the transmission power sequence O of the communication pair. a The matrix is ​​obtained based on the relationship between the transmission power of the communication device and the jamming power of different jamming nodes of the jammer. After performing density-based clustering on the matrix elements, a power relationship vector is obtained. Then, based on the preset first judgment criterion, the power control model of the communication pair is identified; Step 3: For the interfering transmitting nodes l, l = 1, 2, 3, 4, from and The corresponding communication pair power control model parameters are obtained, and the distance ratio from each interfering transmitting node to the hidden communication receiver is calculated. Then, the trajectory equation of the hidden communication receiver's location point is derived from the distance relationship, and the location (x, y) of the hidden communication receiver is solved. Step 4: Based on the obtained communication receiver position (x, y), obtain the channel power gain h for each link. a and Step 5: Based on the constant R and power relationship, Power gain h of each link channel a and Output interference effect evaluation function value 2. The interference effectiveness evaluation method according to claim 1, which does not rely on direct information feedback, is characterized in that, Step 1 includes: Define a jamming system comprising a single-antenna cognitive jammer and a single-antenna communication pair, wherein the cognitive jammer includes a sensing node and a jamming transmitting node; For a communication pair, the positions of the transmitting end a and the receiving end b are q respectively. a =(x a ,y a ) and q b =(x b ,y b Furthermore, during information transmission, the transmission power is dynamically adjusted based on channel conditions and the magnitude of interference. For cognitive jammers, the process of sensing, communication interference decision-making, and effect evaluation based on the OODA loop can be completed autonomously according to task requirements, and the positions of the jamming transmitting node j and the sensing node s are q respectively. j =(x j ,y j ) and q s =(x s ,y s Furthermore, the transmit power of the communication transmitter and the jammer transmitter node are respectively 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 receiver, between the communication transmitter and the jammer sensing node, and between the jammer transmitting node and the communication receiver are respectively expressed as h. a,b h a,s and h j,b , means as follows: Where β0 represents the channel power gain at a reference distance of 1m; the signal-to-interference-plus-noise ratio (SIR) of the communication signal at the receiving end is: Where, σ 2 Let represent the power of the Gaussian white noise; the signal-to-noise ratio of the jammer's sensing node to the communication signal is: in, Indicates the power of Gaussian white noise; The transmission frame protocol for 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, where the transmitting end decides the transmission power of this time slot based on its own power control strategy and feedback; the second stage is the transmission stage, where the transmitting end transmits data at a fixed power; the third stage is the feedback stage, where the receiving end sends back ACK and NACK messages through the control link, providing the transmitting end with link information related to this time slot. The jammer's operating time slot is defined as consisting of three stages: the first stage is the sensing stage, where jammer sensing nodes deployed near the communication transmitter continuously sense the transmission power of the transmitter; the second stage is the decision stage, where the jammer intelligently decides the transmission power of the jamming signal for this time slot based on the sensing information and evaluation results; the third stage is the jamming stage, where the jammer transmitting nodes implement jamming based on the transmission power decided in the previous stage. Only the power control strategy / power anti-jamming behavior of the communication pair is considered, i.e., the frequency occupied does not change during communication. Therefore, the jammer only senses the transmission power of the communication transmitter during the sensing stage. Assuming that the jamming time slot and the communication time slot are synchronized, the data transmission time is equal to the jamming signal transmission time. Assuming that the communication user restarts channel training and makes access decisions in the first time slot of each frame, i.e., 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 the communication pair is represented as follows: in, Let α = h represent the given target signal-to-interference-plus-noise ratio. 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 the communication pair is represented as follows: Where μ is a constant, α = h a,b / (h j,b p j +σ 2 Its value is related to the average transmission power; Greedy model: The communication's power control behavior is represented as follows: Where U(·) represents the utility function of the communication pair, c represents the constant coefficient, and σ 2 h represents the power of Gaussian white noise. a,b and h j,b These represent the channel power gain between the communication transmitter and receiver, and between the jammer transmitter node and the communication receiver, respectively. ε-greedy model: The communication's power control behavior is represented as follows: in, p a ′ represents a random power value in the power set of the communication pair, h a,b and h j,b These represent the channel power gain between the communication transmitter and receiver, and between the jammer transmitter node and the communication receiver, respectively. The signal-to-interference-plus-noise ratio (SIR) decrease of the communication pair is used as an indicator of the effectiveness of the interference. The SIR decrease function for the communication pair in the k-th communication frame and the t-th time slot of frame length T 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-plus-noise ratio (SIR) of the communication pair in the t-th time slot of the k-th communication frame; the cognitive jammer needs to evaluate the SIR of 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 t-th time slot of the k-th communication frame be p. a (k,t), correspondingly, the jamming 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 / awareness, the presence of interference cannot be predicted; therefore, when the communication pair adopts the TCI power control strategy, the transmission power of the communication pair is as follows: Where, σ 2 This represents the power of Gaussian white noise. h represents the given target signal-to-interference-plus-noise ratio (SIN / N). a This represents the channel power gain between the transmitting and receiving ends; however, considering that interference is probabilistic and actually exists, the actual signal-to-interference-plus-noise ratio (SIR) of the communication pair in the current time slot is: Where, σ 2 This represents the power of Gaussian white noise. h represents the given target signal-to-interference-plus-noise ratio (SIN / N). a h represents the channel power gain between the transmitting and receiving ends of a communication connection. j This represents the channel power gain between the jammer transmitting node and the communication receiving end; during the feedback and decision-making phase of the current time slot, the user transmitting end determines the transmit power of the channel to be accessed in the next time slot based on the signal-to-interference-plus-noise ratio of this time slot; therefore, the power of the communication pair in the second time slot of the current frame is: Where, σ 2 This represents the power of Gaussian white noise. h represents the given target signal-to-interference-plus-noise ratio (SIN / N). a h represents the channel power gain between the transmitting and receiving ends of a communication connection. j This represents the channel power gain between the jammer transmitting node and the communication receiving end; at this time, considering the interference situation is less than the threshold, the actual signal-to-interference-plus-noise ratio (SIR) of the communication pair in the second time slot is: Where, σ 2 This represents the power of Gaussian white noise. h represents the given target signal-to-interference-plus-noise ratio (SIN / N). a h represents the channel power gain between the transmitting and receiving ends of a communication connection. j This represents the channel power gain between the jammer transmitting node and the communication receiving end; the signal-to-interference-plus-noise ratio (SIR) of the communication pair in time slot t, t∈[2,T] is: Where, σ 2 This represents the power of Gaussian white noise. h represents the given target signal-to-interference-plus-noise ratio (SIN / N). j This 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: Where, σ 2 This represents the power of Gaussian white noise. h represents the given target signal-to-interference-plus-noise ratio (SIN / N). a h represents the channel power gain between the transmitting and receiving ends of a communication connection. j This represents the channel power gain between the jammer's transmitting node and the communication receiving end; Simplified equation (15) shows that there is a linear positive correlation between the transmission power of the communication signal in time slot t and the interference power in time slot t-1, i.e., the following relationship holds: p a (k,t)=b·p j (k,t-1)+d (17) in, σ 2 This represents the power of Gaussian white noise. h represents the given target signal-to-interference-plus-noise ratio (SIN / N). a h represents the channel power gain between the transmitting and receiving ends of a communication connection. j This represents the channel power gain between the jammer's transmitting node and the communication receiving end; When communication users adopt the WF power control model, the transmit 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, i.e., without considering interference, and the transmit power is as follows: Where, σ 2 The value represents the Gaussian white noise power, μ is a constant related to the average transmitted power, and h is... a This represents the channel power gain between the transmitting and receiving ends; considering interference, the signal-to-interference-plus-noise ratio (SIR) for the communication pair in this time slot is: Where, σ 2 The value represents the Gaussian white noise power, μ is a constant related to the average transmitted power, and h is... a h represents the channel power gain between the transmitting and receiving ends of a communication connection. j This 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: Where, σ 2 The value represents the Gaussian white noise power, μ is a constant related to the average transmitted power, and h is... j This represents the channel power gain between the jammer transmitting node and the communication receiving end; considering the presence of interference, the signal-to-interference-plus-noise ratio (SIR) of the communication pair in the second time slot is: Where, σ 2 The value represents the Gaussian white noise power, μ is a constant related to the average transmitted power, and h is... a h represents the channel power gain between the transmitting and receiving ends of a communication connection. j This represents the channel power gain between the jammer transmitting node and the communication receiving end; the signal-to-interference-plus-noise ratio (SIR) of the communication pair in time slot t, t∈[2,T] is: Where, σ 2 The value represents the Gaussian white noise power, μ is a constant related to the average transmitted power, and h is... a h represents the channel power gain between the transmitting and receiving ends of a communication connection. j This 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: Where, σ 2 The value represents the Gaussian white noise power, μ is a constant related to the average transmitted power, and h is... a h represents the channel power gain between the transmitting and receiving ends of a communication connection. j This represents the channel power gain between the jammer's transmitting node and the communication receiving end; Simplifying equation (23), we find that there is a linear negative correlation between the transmission power of communication in time slot t and the interference power in time slot t-1, i.e., the following relationship holds: p a (k,t)=b′·p j (k,t-1)+d′ (24) in, σ 2 The value represents the Gaussian white noise power, μ is a constant related to the average transmitted power, and h is... a h represents the channel power gain between the transmitting and receiving ends of a communication connection. j This represents the channel power gain between the jammer's transmitting node and the communication receiving end; When the communication pair adopts a greedy transmission strategy, the transmit 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: Where, p a ′ is the random power value, p a,max It is the maximum transmit power of the communication pair; With the channel power gain constant, h a,b / (pj(k,t- 1 )·h j,b +σ 2 -c is a function that is only affected by p j (k,t-1) are the variables affected; as the interference power gradually increases, the transmission power of the communication pair abruptly drops to 0. At this point, the interference power is the cutoff power, with a value of p. j,cut-off =(h a,b / c-σ 2 ) / h j,b ; When the communication pair adopts the ε-greedy transmission model, the transmit power in the first time slot of each frame is as follows: Therefore, the transmission power of the communication pair in time slot t, t∈[2,T] is: Where, p′ a It is a random power value, p a,max It is the maximum transmit power of the communication pair; Similarly, the relationship between the transmit power of the communication pair in time slot t and the interference power in time slot t-1 can be obtained; by observing and analyzing the relationship between the transmit power and interference power of the communication pair, a power control model for the communication pair can be classified.

3. The interference effectiveness evaluation method according to claim 2, which does not rely on direct information feedback, is characterized in that, Step 2 includes: During interference induction, the jammer power is made discrete, i.e.: Where Δ is the number of equally divided intervals. p j,max This is the maximum transmit power of the jammer, p j (k,t) represents the jamming power of the jammer in the t-th time slot of the k-th frame; let the jamming induction period be M, M<T, and in each period, the jammer transmitting node transmits signals in ascending power order, thereby obtaining the power sequence O of the communication pair's transmitting end. a ={p i,n |i∈[1,M],n∈[1,Δ]}, where This yields the following power relationship matrix: The matrix elements are mapped to points in the power graph. After density-based clustering, the matrix... From vector It is expressed as follows: Where Δ is the number of equally divided intervals, p j,max This is the maximum transmit power of the jammer; according to the first judgment criterion, it is determined by the matrix. sum vector Determine the power control model of the communication pair; The first judgment criterion process is as follows: The first step is to determine the matrix. If all columns are the same, proceed to step two; otherwise, determine it as an ε-greedy model. The second step is to observe the vectors. If the first few elements n << Δ, and the interference power is positively correlated with the transmission power of the communication pair, it is determined to be a TCI model; if they are 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.

4. The interference effectiveness evaluation method according to claim 3, which does not rely on direct information feedback, is characterized in that, Step 3 includes: Analysis was conducted on specific power control models to obtain expressions for the hidden receiver location under different models; TCI Model: The relationship between the transmit power of a communication pair in time slot t and the interference power in time slot t-1 is given by... and When the characteristics are known, the coefficients b and d in equation (17) showing a linear positive correlation between the communication transmit power in time slot t and the interference power in time slot t-1 can be determined; the h between different interference nodes and the communication receiver j,b They are different, and the signal-to-interference-plus-noise ratio target of the communication pair is different. and h a It remains unchanged; therefore, considering the line-of-sight link model, the channel power gain from the four interfering nodes to the communication receiver is constant. and Satisfy the following relations: Among them, κ l The values ​​l = 1, 2, 3, and 4 are obtained from the slopes of the curves showing the relationship between the transmission power of the communication pair and the interference power between the four interfering nodes; the ratio of the distances from the four interfering nodes to the communication receiver is: Let the positions of the four interfering nodes be (x1, y1), (x2, y2), (x3, y3), and (x4, y4), and the position of the communication receiver be (x, y). The receiver's coordinate trajectory, satisfying the ratio of its distances to the interfering nodes j1 and j2, satisfies the following: Simplifying equation (34) yields: According to equation (35), when k1≠k2, the receiver position trajectory is a circle; while when k1≠k2, the trajectory is a straight line, namely the perpendicular bisector of the two jammer position points. Find the trajectory of the position points that satisfy the other two sets of relationships, and find the hidden location of the communication receiver by the intersection of the trajectories; WF model: The coefficients b′, d′ in equation (24) are easily obtained; therefore, the channel power gain from the four interfering nodes to the communication receiver is... and Satisfy the following relations: Among them, κ l The values ​​l = 1, 2, 3, 4 are obtained from the slope of the curve showing the relationship between the transmission power of the communication pair and the interference power between the four interfering nodes; the coordinates of the communication receiver position also satisfy the following: After obtaining the other two sets of trajectory relationships, the position (x, y) of the communication receiver 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 Given the cutoff power values ​​corresponding to the four interference nodes. Afterwards, due to h a,b ,c,σ 2 The channel power gain from all four interfering nodes to the communication receiver is the same for all different interfering nodes. and The relationship between them is expressed as follows: have to: After obtaining the relationship shown in equation (39), the position (x, y) of the communication receiver is determined; The localization process of the communication receiver under the ε-greedy model is the same as that under the greedy model.

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

6. The interference effectiveness evaluation method according to claim 5, which does not rely on direct information feedback, is characterized in that, Step 5 includes: After obtaining h a and Then, the signal-to-interference-plus-noise ratio (SIR) decrease rate function of the k-th frame and t-th time slot of the communication pair is estimated as follows: Where R is a set constant, h a This represents the channel power gain between the transmitting and receiving ends of the communication. σ represents the channel power gain between the jammer's transmitting node l and the communication receiving end. 2 p is the white noise power. a (k,t) represents the transmission power of the communication pair in the t-th time slot of the k-th frame. Let represent the transmit power of jammer transmitting node l; in equation (41), only the communication link noise power σ is considered. 2 Since it is unknown, the noise power is estimated as follows: Where η is the noise power coefficient. This represents the channel power gain between the jammer's transmitting node l and the communication receiving end. This indicates the transmit power of the jammer's transmitting node l; thus, the cognitive jammer obtains the jamming effectiveness in different time slots.

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