Communication anti-interference method assisted by multiple closed intelligent reflecting surfaces on receiving side

Abstract

The invention discloses a communication anti-interference method assisted by a plurality of closed intelligent reflecting surfaces on a receiving side, and the method comprises the steps: constructing a closed space selection structure formed by a plurality of RIS panels in a surrounding manner, placing a receiving antenna in the closed space selection structure, and enabling each RIS unit to independently regulate and control the transmission or reflection state of incident electromagnetic waves; according to the relative position of a receiving antenna and an external signal source, the space outside the structure is divided into different signal areas, and each signal area is covered by an RIS panel; and according to the signal area where the signal source is located, adjusting the working mode of the RIS unit of each signal area: adjusting the RIS unit of the signal area where the signal source is located to a transmission mode, and adjusting the RIS units of other signal areas to a reflection mode. According to the invention, the reachable transmission rate and the anti-interference capability of a communication system are improved, the problem of signal interference in a complex environment is solved, and efficient and reliable communication in a complex interference environment is realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of wireless communication, in particular to a receiving side closed multi-intelligent reflective surface assisted communication anti-interference method. BACKGROUND

[0002] With the continuous development of modern communication technology, communication interference means is constantly updated, and higher requirements are put forward for the anti-interference technology of communication system. As a new type of electromagnetic regulation technology, reconfigurable intelligent surface can optimize the propagation environment of wireless channel by actively regulating the propagation characteristics of electromagnetic wave such as phase, amplitude, polarization and scattering direction, so as to meet the increasingly high anti-interference requirements of communication system. Beamforming technology is a kind of adaptive antenna technology based on statistical estimation, and its core goal is to minimize the mean square error between the output signal and the expected signal, so as to optimize the receiving or transmitting performance in complex interference environment. The present application combines the two technologies, which can greatly improve the achievable transmission rate of the communication system.

[0003] Reconfigurable intelligent surface has selective transmission / reflection capability, which can filter out interference signals by regulating the amplitude response of the unit, and only allow useful signals to be transmitted or reflected to the target terminal; at the same time, by regulating the phase characteristics of the incident electromagnetic wave, the phase difference of the incident electromagnetic wave is converted into a controllable phase distribution, so as to optimize the communication environment. The receiving beamforming technology regulates the phase and amplitude of the antenna array by adjusting the weighting coefficient of the receiving antenna array, so as to focus the electromagnetic wave energy on the target direction and suppress the interference and loss in other directions. The combination of receiving beamforming technology and reconfigurable intelligent surface for alternative optimization of reflected beamforming can solve the problem of signal interference in complex environment and realize efficient and reliable communication in complex interference environment. SUMMARY

[0004] The present application aims to provide a receiving side closed multi-intelligent reflective surface assisted communication anti-interference method with strong anti-interference ability and high reliability.

[0005] The technical solution for achieving the purpose of the present application is as follows: a receiving side closed multi-intelligent reflective surface assisted communication anti-interference method, comprising the following steps:

[0006] A closed space selection structure surrounded by a plurality of intelligent reflective surfaces (RIS) is constructed, and a receiving antenna is placed inside the space selection structure, and each RIS unit can independently regulate the transmission or reflection state of the incident electromagnetic wave;

[0007] According to the relative position of the receiving antenna and the external signal source, the space outside the closed space selection structure is divided into different signal regions, and each signal region is covered by a RIS panel;

[0008] According to the signal area where the signal source is located, the working mode of the RIS unit of each signal area is adjusted:

[0009] (1) When the signal source and the interference source are located in different signal areas, the RIS unit in the signal area where the signal source is located is controlled to work in the transmission mode, and the RIS units in all other areas are controlled to work in the reflection mode;

[0010] (2) When the signal source and the interference source are located in the same signal area, the RIS unit corresponding to the signal area is controlled to work in the transmission mode, and the RIS units in all other areas are controlled to work in the reflection mode.

[0011] A receiving side closed multi-intelligent reflecting surface assisted communication anti-interference system, which is used to realize the receiving side closed multi-intelligent reflecting surface assisted communication anti-interference method.

[0012] A mobile terminal, comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, wherein the processor executes the program to realize the receiving side closed multi-intelligent reflecting surface assisted communication anti-interference method.

[0013] A computer readable storage medium, having a computer program stored thereon, wherein the program is executed by a processor to realize the steps in the receiving side closed multi-intelligent reflecting surface assisted communication anti-interference method.

[0014] Compared with the prior art, the present application has the following advantages:

[0015] (1) The amplitude response of the control unit can be adjusted to filter out interference signals and allow only useful signals to be transmitted or reflected to the target terminal; at the same time, the phase characteristics of the incident electromagnetic wave are adjusted to compensate for the phase of the incident electromagnetic wave, converting the random phase difference into a controllable phase distribution, thereby optimizing the communication environment;

[0016] (2) The achievable transmission rate and anti-interference ability of the communication system are improved, the signal interference problem in complex environment is solved, and efficient and reliable communication in complex interference environment is realized. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 Fig. 1 is a structural schematic diagram of the receiving side closed multi-intelligent reflecting surface assisted communication anti-interference system of the present application.

[0018] Figure 2 Fig. 2 is a principle schematic diagram of the communication system model in the embodiment of the present application.

[0019] Figure 3Fig. 1 is a graph showing the relationship between the number of iterations and the system achievable rate when the user transmitter and the interferer are in the same RIS region with different transmission powers in an embodiment of the present application.

[0020] Figure 4 Fig. 2 is a graph showing the system achievable rate as a function of signal transmission power when the user transmitter and the two interferers are in the same region and different regions respectively in the double RIS, single RIS and no RIS cases in an embodiment of the present application.

[0021] Figure 5 Fig. 3 is a graph showing the system achievable rate as a function of the number of RIS elements when the user transmitter and the two interferers are in the same region and different regions respectively in the double RIS and single RIS cases in an embodiment of the present application. DETAILED DESCRIPTION

[0022] The present application provides a receiving side closed multi-intelligent reflective surface assisted communication anti-jamming method, comprising the following steps:

[0023] A closed space selection structure surrounded by a plurality of intelligent reflective surfaces (RIS panels) is constructed, and a receiving antenna is placed inside the space selection structure. Each RIS unit can independently control the transmission or reflection state of the incident electromagnetic wave.

[0024] According to the relative positions of the receiving antenna and the external signal source, the space outside the closed space selection structure is divided into different signal regions, and each signal region is covered by one RIS panel.

[0025] According to the signal region where the signal source is located, the working mode of the RIS unit of each signal region is adjusted.

[0026] (1) When the signal source and the interference source are located in different signal regions, the RIS unit in the signal region where the signal source is located is controlled to work in the transmission mode, and the RIS units in all other regions are controlled to work in the reflection mode.

[0027] (2) When the signal source and the interference source are located in the same signal region, the RIS unit corresponding to the signal region is controlled to work in the transmission mode, and the RIS units in all other regions are controlled to work in the reflection mode.

[0028] As a specific example, the RIS unit in the signal region where the signal source is located is adjusted to the transmission mode, and the RIS units in the remaining signal regions are adjusted to the reflection mode. The specific parameters of the adjustment are configured with the optimization objective of maximizing the received signal-to-interference-plus-noise ratio (SINR), and the optimization process includes the following steps:

[0029] Step 1, based on the regional positions of the signal source and the interference source, set the initial working mode of the RIS unit.

[0030] Step 2, fine-tune the parameters of the RIS unit on the basis of the initial working mode;

[0031] Step 3, determine the final working mode parameters according to the change of SINR.

[0032] As a specific example, the initial working mode of the RIS unit is set based on the area position of the signal source and the interference source in step 1, which is as follows:

[0033] The source signal of the user transmitter is , and the transmission power is ; the interference signal of the interference source is , and the transmission power is ; the equivalent channel between the user transmitter and the base station is , and the equivalent channel between the interference machine and the base station is ; it is assumed that there are three distributed RIS panels, and the three distributed RIS panels, namely RIS1, RIS2 and RIS3, are composed of , and units respectively; is the channel from the user transmitter to the base station, is the channel from the user transmitter to RIS1, is the channel from the user transmitter to RIS2, is the channel from the kth interference machine to the base station, is the channel from the kth interference machine to RIS1, is the channel from the kth interference machine to RIS2, is the channel from RIS1 to RIS2, is the channel from RIS2 to RIS1, is the channel from RIS1 to the base station, is the channel from RIS2 to the base station; represents the diagonal reflection coefficient matrix of RIS , represents the reflection coefficient of RIS ; the user transmitter and the interference machine of the interference source send signals at the same time, the receiving end receives the source signal and the interference signal by using N-way antenna, and linear beam forming is used, and the beam forming vector is ;

[0034] The equivalent channel between the user transmitter and the base station is , which is expressed as:

[0035] (1)

[0036] Similarly, the equivalent channel between the jammer and the base station is is denoted as:

[0037] (2)

[0038] To maximize the reception of the user transmitter signal and suppress the interference signal in the communication system, the following settings are made:

[0039] Setting 1: All channels are quasi-static flat fading channel models, and the CSI of all cascaded channels is available at the base station.

[0040] Setting 2: The three distributed RIS units are composed of , and units, which use passive self-capable controllers to adjust the phase shift of the incident signal, and all reflection amplitudes are uniform to the maximum value, i.e. ;

[0041] Setting 3: It is considered that there is a direct link, a one-time reflection link and a two-time reflection link in the communication system, and the influence of three times and above is ignored.

[0042] Setting 4: The noise is additive white Gaussian noise.

[0043] As a specific example, step 2 is based on the initial operating mode to fine-tune the parameters of the RIS unit, which is as follows:

[0044] Initialize the reflection coefficient of the distributed RIS unit and the receive beamforming vector ;

[0045] Randomize the reflection coefficient of the phase of the distributed RIS unit, randomize the phase offset, and the reflection amplitude is uniform to the maximum value, i.e. , and the beamforming vector at the receiving end is randomly generated and normalized, and the signal-to-interference-and-noise ratio of this communication system is denoted as:

[0046] (3)

[0047] The optimization goal is to jointly optimize the receive beamforming vector and the reflection coefficient of the distributed RIS unit to maximize the signal-to-interference-and-noise ratio of the system, so the problem P1 is denoted as:

[0048] (4)

[0049] Problem P1 is a non-convex optimization problem. Due to the non-concave objective function in equation (3) and the non-convex unit modulus constraint in equation (4), problem P1 is difficult to solve. Therefore, problem P1 is expressed as problem P2:

[0050] (5)

[0051] Since problem P2 is still nonconvex, and due to the unit modulus constraint and , The coupling between the two factors makes it difficult to find the optimal solution. Therefore, we alternately optimize the reflection coefficients, optimizing one of them while keeping the other fixed. Problem P2 can be represented as problem P3:

[0052] (6)

[0053] This problem remains non-convex; we can perform an equivalent transformation:

[0054] (7)

[0055] Further, let's represent problem P4 as problem P5:

[0056] (8)

[0057] Further definition ,satisfy and ,because This constraint is non-convex, so we relax it, thus transforming problem P5 into a semi-positive definite programming problem P6, which can be solved using the bisection method:

[0058] (9)

[0059] By using Gaussian randomization to obtain the best possible solution, based on a given beamforming vector... and the reflection coefficient of RIS2 The reflection coefficient of RIS1 was obtained. ;

[0060] The reflection coefficients of the remaining RIS units are determined as follows: based on the given beamforming vector. and the reflection coefficient of RIS1 The problem is solved using positive semidefinite relaxation and the bisection method, and Gaussian randomization is performed to obtain the reflection coefficients of RIS2. ;

[0061] Based on the reflection coefficients of all RIS units, the beamforming vector is obtained by solving the beamforming problem using MMSE, as follows:

[0062] For a fixed reflection coefficient and reflection coefficient The beamforming vector is obtained by solving the minimum mean square error receiver beamforming. :

[0063] (10)

[0064] in, This represents the channel matrix at the equivalent base station.

[0065] The present invention also provides a communication anti-interference system assisted by a closed-loop multi-intelligent reflector on the receiving side, which is used to implement the aforementioned communication anti-interference method assisted by a closed-loop multi-intelligent reflector on the receiving side.

[0066] The present invention also provides a mobile terminal, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, it implements the aforementioned communication anti-interference method assisted by a closed-type intelligent reflector on the receiving side.

[0067] The present invention also provides a computer-readable storage medium having a computer program stored thereon, wherein the program, when executed by a processor, implements the steps in the receiver-side closed multi-intelligent reflector-assisted communication anti-interference method.

[0068] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0069] Example

[0070] Figure 1 This is a schematic diagram of the multi-RIS cooperative communication anti-interference system provided in this embodiment. The transmitting end consists of a user single-antenna transmitter and an interfering single-antenna jammer, while the receiving end consists of a base station and multiple distributed RIS. The receiving base station has N independent antennas, and multiple distributed RIS are deployed around it, surrounding the base station and dividing the transmitting end location into multiple areas according to the RIS deployment method. When the user transmitter and the interfering jammer transmit user transmitter signals and interference signals simultaneously, the jammer's transmitted signals are directly blocked by the corresponding RIS, while the user transmitter remains unaffected and communicates with the base station. When the user transmitter and the interfering jammer transmit user transmitter signals and interference signals simultaneously, the communication anti-interference method with closed multi-intelligent reflector assistance proposed in this invention maximizes the signal-to-interference-plus-noise ratio (SINR) of the communication system, maximizing the reception of user transmitter signals while suppressing interference signals, thereby achieving effective and reliable wireless communication.

[0071] Construct an anti-interference communication system model based on receiving beamforming and reconfigurable smart surfaces, such as... Figure 2As shown, the user transmitter source signal is set to... The transmission power is The jamming party has a total of K jammers, and the jamming signals they send are as follows: The transmission powers are respectively The equivalent channel between the user transmitter and the base station is The equivalent channel between the jammer and the base station is There are three distributed RIS systems, each consisting of a different component. , and Individual surface composition; For the channel between the user transmitter and the base station, For the channel between the user transmitter and RIS1, For the channel between the user transmitter and RIS2, Let k be the channel between the jammer and the base station. For the channel between the k-th jammer and RIS1, For the channel between the k-th jammer and RIS2, For the channel between RIS1 and RIS2, For the channel between RIS2 and RIS1, This is the channel between RIS1 and the base station. This is the channel between RIS2 and the base station; Represents RIS The diagonal reflection coefficient matrix, Represents RIS The reflection coefficient; the user transmitter and the jammer send signals at the same time, and the receiver uses N antennas to receive the source signal and the jamming signal, and uses linear beamforming, with the beamforming vector... ;

[0072] The equivalent channel between the transmitter and the base station is Represented as:

[0073]

[0074] in, , ;

[0075] Similarly, the equivalent channel between the jammer and the base station is Represented as:

[0076]

[0077] in, , ;

[0078] To maximize the reception of user transmitter signals while suppressing interference signals, the following settings are made in the communication system:

[0079] Setting 1: All channels are quasi-static flat fading channel models, and the CSI of all cascaded channels is available at the base station;

[0080] Setting 2: The three distributed RIS are respectively... , and The system consists of several sub-surfaces, each of which uses a self-powered controller to adjust the phase shift of the incident signal, and all reflection amplitudes are uniformly set to their maximum value. ;

[0081] Setting 3: It is assumed that there are direct links, first-stage reflection links, and second-stage reflection links in the communication system, and the influence of third-stage and higher reflection links is ignored;

[0082] Setting 4: The noise is additive white Gaussian noise.

[0083] Initialize the reflection coefficients of the distributed RIS and the base station receiving beamforming vector, construct the signal-to-interference-plus-noise ratio (SINR) function of the communication system, and simplify the objective problem as follows:

[0084] Initialize the reflection coefficient of the distributed RIS and receive beamforming vector ;

[0085] The reflection coefficients of different sub-surfaces of the distributed RIS are randomized, the phase shift is randomized, and the reflection amplitude is uniformly represented by the maximum value, i.e. Simultaneously, the beamforming vector at the receiving end is randomly generated and normalized. The signal-to-interference-plus-noise ratio (SIR) of this communication system is expressed as:

[0086]

[0087] The optimization objective is to jointly optimize the receiver beamforming vector and the distributed RIS reflection coefficient to maximize the signal-to-interference-plus-noise ratio (SIR) of the system. Therefore, problem P1 can be represented as:

[0088]

[0089] Problem P1 is a non-convex optimization problem. Due to the non-concave objective function in equation (3) and the non-convex unit modulus constraint in equation (4), this problem is difficult to solve. Therefore, this problem is represented as P2:

[0090]

[0091] For any RIS's reflection coefficient, based on a given beamforming vector and the reflection coefficients of the other RISs, the problem is solved using positive semidefinite relaxation and the bisection method, and Gaussian randomization is performed to obtain the reflection coefficient of this RIS, as follows:

[0092] Since problem P2 is still nonconvex, and due to the unit modulus constraint and and The coupling between the two factors makes it difficult to find the optimal solution. Therefore, the reflection coefficients are optimized alternately, with one reflection coefficient optimized while the other remains fixed. Specifically, for a fixed beamforming vector... and the reflection coefficient of RIS2 The equivalent channel between the transmitter and the base station Reflection coefficient Linear representation of:

[0093]

[0094] in, ;

[0095] Similarly, the equivalent channel between the transmitter and the base station... Reflection coefficient The linear representation of is:

[0096]

[0097] in, At this point, problem P2 can be represented as problem P3:

[0098]

[0099] in, , , , This problem remains non-convex and can be equivalently transformed:

[0100]

[0101] in, ; .

[0102] Further, problem P4 can be represented as:

[0103]

[0104] Further definition ,satisfy and ,because This constraint is non-convex, so relaxing it transforms problem P5 into a semi-positive definite programming problem P6, which can be solved efficiently using the bisection method.

[0105]

[0106] By using Gaussian randomization to obtain the best possible solution, based on a given beamforming vector... and the reflection coefficient of RIS2 The reflection coefficient of RIS1 was obtained. .

[0107] Using the same method, the reflection coefficients of the remaining RIS were obtained, as follows:

[0108] Based on a given beamforming vector and the reflection coefficient of RIS1 The problem is solved using positive semidefinite relaxation and the bisection method, and Gaussian randomization is performed to obtain the reflection coefficients of RIS2. At this point, the equivalent channel between the transmitter and the base station is... Reflection coefficient Linear representation of:

[0109]

[0110] in, .

[0111] The equivalent channel between the jammer and the base station Reflection coefficient Linear representation of:

[0112]

[0113] in, The problem of finding the maximum signal-to-interference-plus-noise ratio can be transformed into a problem of the same form (P7):

[0114]

[0115] in ,satisfy and , , , , .

[0116] Based on the reflection coefficients of all RIS obtained, the beamforming vector is obtained by solving the receiver beamforming algorithm using MMSE, as follows:

[0117] For a fixed reflection coefficient and reflection coefficient The beamforming vector is obtained by solving the minimum mean square error receiver beamforming. :

[0118]

[0119] in, This represents the channel matrix at the equivalent base station.

[0120] The RIS reflection coefficient and the received beamforming vector are iteratively updated until the signal-to-interference-plus-noise ratio of the communication system converges to its maximum value.

[0121] consider Figure 2 The communication anti-interference application scenario shown assumes that the user transmitter and the jammer are located in the same RIS area, and the user transmitter sends the original signal as... The jammer sends the following signal: The transmission power is 30dBm. The number of antennas at the user transmitter and the jammer is 1, while the number of antennas at the receiving base station is N=4. The noise signal follows a Gaussian distribution and... Each RIS panel consists of 16 RIS array elements.

[0122] Figure 3 This paper demonstrates the relationship between the system's achievable rate and the number of iterations when the user transmitter and the jammer are located in the same RIS region and the transmit power is 27dBm, 30dBm, and 33dBm, respectively. It can be seen that under different transmit power conditions, the proposed alternating optimization algorithm effectively improves the system's achievable rate and converges quickly within 5 iterations, verifying the algorithm's good effectiveness and convergence performance. Furthermore, with the jamming power remaining constant, the higher the user transmitter power, the higher the achievable rate after system optimization.

[0123] Figure 4The achievable rate of the system under dual-RIS, single-RIS, and no-RIS configurations was compared when the user transmitter and two jammers were located in the same area and in different areas, specifically in the areas belonging to RIS2 and RIS3, respectively. To ensure simulation fairness, the single-RIS system was configured with a total array element count of M, while the dual-RIS system had M / 2 array elements per panel, maintaining a consistent total array element count. To reduce the impact of randomness, 60 independent simulations were performed at each power point, and the average value was taken. Each simulation iteration consisted of 6 iterations, and the algorithm converged within 5 iterations. The results show that the achievable rate of the system improves with increasing transmit power in all three configurations, and the multi-RIS structure proposed in this invention consistently outperforms the single-RIS and no-RIS cases. Under the same jamming conditions and total array element count, the dual-RIS structure achieves an average rate gain of approximately 1 bit / s / Hz compared to the single-RIS structure, effectively verifying the advantages of the structure in this invention in improving system communication effectiveness.

[0124] Figure 5 This study demonstrates how the achievable data rate of the system changes with the total number of RIS elements in dual-RIS and single-RIS configurations, with the user transmitter and two jammers located in the same and different areas, respectively. The transmit power is fixed at 30 dBm. To ensure a fair comparison, the single-RIS system has a total of M elements, while the dual-RIS system has M / 2 elements per panel, maintaining a consistent total number of elements. Simulation results show that the achievable data rate of both dual-RIS and single-RIS systems significantly increases with the increase in the total number of RIS elements, with a more significant increase in the dual-RIS structure. This indicates that increasing the number of RIS elements effectively improves the system's transmission performance and also verifies that the multi-RIS structure is more efficient in utilizing element resources, contributing to enhanced effectiveness and reliability of the communication system.

[0125] In summary, the communication anti-interference method with receiver-side closed multi-intelligent reflector assistance proposed in this invention is reliable and effective, and has strong practicality in communication environments where interference exists.

[0126] The above are merely preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A communication anti-interference method assisted by a closed-loop multi-intelligent reflector on the receiving side, characterized in that, Specifically as follows: Construct a closed spatial selection structure surrounded by multiple intelligent reflective surfaces, i.e., RIS panels, and place the receiving antenna inside the spatial selection structure. The units in each RIS panel can independently adjust the transmission or reflection state of the incident electromagnetic wave. Based on the relative position of the receiving antenna and the external signal source, the space outside the enclosed space selection structure is divided into different signal areas, and each signal area is covered by a RIS panel. Adjust the operating mode of the RIS units in each signal region according to the signal region where the signal source is located: (1) When the signal source and the interference source are located in different signal regions, the RIS unit in the signal region where the signal source is located is controlled to work in transmission mode, while the RIS units in all other regions are controlled to work in reflection mode. (2) When the signal source and the interference source are located in the same signal area, the RIS unit corresponding to the signal area is controlled to work in the transmission mode, while the RIS units in all other areas are controlled to work in the reflection mode.

2. The communication anti-interference method assisted by a closed-type multi-intelligent reflector on the receiving side according to claim 1, characterized in that, The RIS units in the signal region where the signal source is located are adjusted to transmission mode, and the RIS units in other signal regions are adjusted to reflection mode. The specific parameters for adjustment are configured with the optimization objective of maximizing the signal-to-interference-plus-noise ratio (SINR) at the receiver. The optimization process includes the following steps: Step 1: Based on the regional locations of the signal source and interference source, set the initial operating mode of the RIS unit; Step 2: Based on the initial operating mode, fine-tune the parameters of the RIS unit; Step 3: Determine the final operating mode parameters based on the changes in SINR.

3. The communication anti-interference method assisted by a closed-type multi-intelligent reflector on the receiving side according to claim 2, characterized in that, Step 1 involves setting the initial operating mode of the RIS unit based on the regional locations of the signal source and interference source, as detailed below: Set the user transmitter source signal to The transmission power is The jamming party has a total of K jammers, and the jamming signals they send are as follows: The transmission powers are respectively The equivalent channel between the user transmitter and the base station is The equivalent channel between the jammer and the base station is Assume there are three distributed RIS panels, namely RIS1, RIS2, and RIS3, respectively... , and It consists of several units; For the channel between the user transmitter and the base station, For the channel between the user transmitter and RIS1, For the channel between the user transmitter and RIS2, Let k be the channel between the jammer and the base station. For the channel between the k-th jammer and RIS1, For the channel between the k-th jammer and RIS2, For the channel between RIS1 and RIS2, For the channel between RIS2 and RIS1, This is the channel between RIS1 and the base station. This is the channel between RIS2 and the base station; Represents RIS The diagonal reflection coefficient matrix, Represents RIS The reflection coefficient; the user transmitter and the jammer send signals at the same time, and the receiver uses N antennas to receive the source signal and the jamming signal, and uses linear beamforming, with the beamforming vector... ; The equivalent channel between the user transmitter and the base station is Represented as: （1） Similarly, the equivalent channel between the jammer and the base station is Represented as: （2） To maximize the reception of user transmitter signals while suppressing interference signals, the following settings are made in the communication system: Setting 1: All channels are quasi-static flat fading channel models, and the CSI of all cascaded channels is available at the base station; Setting 2: The three distributed RIS panels are respectively composed of... , and Composed of several units, these RIS units use a passive power controller to adjust the phase shift of the incident signal, and all reflection amplitudes are uniformly set to the maximum value, i.e. ; Setting 3: It is assumed that there are direct links, first-stage reflection links, and second-stage reflection links in the communication system, and the influence of third-stage and higher reflection links is ignored; Setting 4: The noise is additive white Gaussian noise.

4. The communication anti-interference method assisted by a closed-type multi-intelligent reflector on the receiving side according to claim 3, characterized in that, Step 2 involves fine-tuning the parameters of the RIS unit based on the initial operating mode, as detailed below: Initialize the reflection coefficient of the distributed RIS unit and receive beamforming vector ; The reflection coefficients of the distributed RIS unit phase are randomized, the phase offset is randomized, and the reflection amplitude is uniformly represented as the maximum value, i.e. Simultaneously, the beamforming vector at the receiving end is randomly generated and normalized. The signal-to-interference-plus-noise ratio (SIR) of this communication system is expressed as: （3） The optimization objective is to jointly optimize the receiver beamforming vector and the reflection coefficient of the distributed RIS unit to maximize the signal-to-interference-plus-noise ratio of the system. Therefore, problem P1 can be represented as: （4） Problem P1 is a non-convex optimization problem. Due to the non-concave objective function in equation (3) and the non-convex unit modulus constraint in equation (4), problem P1 is difficult to solve. Therefore, problem P1 is expressed as problem P2: （5） Since problem P2 is still nonconvex, and due to the unit modulus constraint and , The coupling between the two factors makes it difficult to find the optimal solution. Therefore, we alternately optimize the reflection coefficients, optimizing one of them while keeping the other fixed. Problem P2 can be represented as problem P3: （6） This problem remains non-convex; we can perform an equivalent transformation: （7） Further, let's represent problem P4 as problem P5: （8） Further definition ,satisfy and ,because This constraint is non-convex, so we relax it, thus transforming problem P5 into a semi-positive definite programming problem P6, which can be solved using the bisection method: （9） By using Gaussian randomization to obtain the best possible solution, based on a given beamforming vector... and the reflection coefficient of RIS2 The reflection coefficient of RIS1 was obtained. ; The reflection coefficients of the remaining RIS units are determined as follows: based on the given beamforming vector. and the reflection coefficient of RIS1 The problem is solved using positive semidefinite relaxation and the bisection method, and Gaussian randomization is performed to obtain the reflection coefficients of RIS2. ; Based on the reflection coefficients of all RIS units, the beamforming vector is obtained by solving the beamforming problem using MMSE, as follows: For a fixed reflection coefficient and reflection coefficient The beamforming vector is obtained by solving the minimum mean square error receiver beamforming. : （10） in, This represents the channel matrix at the equivalent base station.

5. A receiver-side enclosed multi-intelligent reflector-assisted communication anti-interference system, characterized in that, This system is used to implement the communication anti-interference method with receiver-side closed multi-intelligent reflector assistance as described in any one of claims 1 to 4.

6. A mobile terminal, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the communication anti-interference method with closed-type multi-intelligent reflector-assisted communication as described in any one of claims 1 to 4.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the steps in the communication anti-interference method assisted by the closed multi-intelligent reflector on the receiving side as described in any one of claims 1 to 4.

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