Sensing-assisted vortex electromagnetic wave anti-interference method, device and system

Abstract

The invention discloses a perception-assisted vortex electromagnetic wave anti-interference method, device and system, and the method comprises the steps: estimating the position information of an interference source based on an interference signal received by a transmitting end through employing an EMUSIC combined RSS algorithm, and obtaining the state information of an interference channel according to the position information; based on known complete channel state information of a receiving and transmitting end, designing a receiving and transmitting joint phase matrix, and eliminating inter-mode interference; according to the estimated interference channel state information, the sending end decomposes an interference signal to each mode, and selects L modes with the minimum interference influence as carriers for multiplexing transmission of L paths of signals; the transmitting end carries out power distribution on the L-path multiplexing signals so as to realize maximum spectrum efficiency under interference; the receiving end carries out modal solution on the received signal and recovers each modal signal so as to realize interference suppression; the problem that the anti-interference effect of vortex electromagnetic wave communication is poor under the condition that interference channel state information is unknown is solved, and the reliability of a communication system is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of wireless communications and relates to a sensing-assisted vortex electromagnetic wave anti-interference method, device and system. Background Art

[0002] Wireless communication systems play a vital role in modern communication networks. However, due to the openness and broadcast nature of their channels, the systems are extremely vulnerable to malicious interference attacks, resulting in a significant decrease in communication quality. In order to meet this challenge, scholars in academia and industry have conducted in-depth research on improving the anti-interference capabilities of wireless communications, in order to improve information transmission efficiency while ensuring communication quality.

[0003] At present, frequency hopping technology is the mainstream technology in the field of wireless communication anti-interference. This technology reduces the probability of legitimate signals being interfered with by rapidly changing the carrier frequency between the legitimate transmitter and the receiver according to a pre-set frequency hopping pattern. However, when facing co-channel interference attacks, the anti-interference ability of frequency hopping technology seems to be insufficient. Therefore, exploring new anti-interference technologies to significantly improve the anti-interference ability of wireless communication systems under co-channel interference has become an urgent need for current research.

[0004] In recent years, orbital angular momentum (OAM) has provided a robust method to enhance the physical layer security of wireless communications without consuming additional resources such as time, frequency, power and code. It has attracted much attention due to its unique spiral phase wavefront characteristics. The number of modes of the vortex electromagnetic waves generated by the uniform circular array (UCA) antenna is theoretically equal to the number of UCA array elements. In ideal line of sight (LoS) communication, the orthogonality between different integer OAM modes allows multiple data streams to be transmitted in parallel without inter-modal interference, thus showing great anti-interference potential without sacrificing spectrum resources.

[0005] In order to further enhance the anti-interference capability of OAM wireless communication systems, the academic community has proposed a variety of innovative solutions. For example, the anti-interference performance of OAM radar systems is enhanced by introducing frequency-agile signals, the difficulty of predicting interference signal parameters is increased by using the jumping characteristics of frequency-agile signals, and the problem of obtaining target azimuth information is solved by using compressed sensing algorithms. In addition, a multi-modal vortex radar anti-interference solution based on waveform diversity has also been proposed. This solution combines OAM modes and waveform diversity technology to expand the signal space dimension of traditional radar systems to enhance the ability to identify and suppress digital RF memory interference.

[0006] Another innovative anti-interference solution is the vortex electromagnetic wave mode-hopping anti-interference technology. This technology quickly switches the vortex electromagnetic wave mode through the pre-shared mode-hopping sequence between the transmitter and the receiver to reduce the probability of interference to the own signal. This method extends the anti-interference method from the traditional frequency domain to the two-dimensional mode-frequency domain, enriches the diversity of the partner's signal transmission carrier, and significantly reduces the probability of interference.

[0007] However, although vortex electromagnetic wave anti-interference technology shows great potential, it still faces some challenges in practical applications. When the transmitter and the receiver are not aligned in parallel, the orthogonality between different modes will be destroyed, resulting in a decrease in the anti-interference performance of the vortex electromagnetic wave wireless communication system. Especially in the face of complex broadband interference environments and when the interference channel state information (CSI) is unknown, existing anti-interference technologies are difficult to achieve ideal anti-interference effects. Therefore, how to make full use of the orthogonality between vortex electromagnetic wave modes in the case of unknown interference channel state information and improve the anti-interference capability of wireless communication systems has become a technical problem that needs to be solved urgently. Summary of the invention

[0008] The purpose of the present invention is to solve the problem that when the transmitting end and the receiving end are not aligned in parallel in the prior art, the orthogonality between different modes will be destroyed, resulting in a decrease in the anti-interference performance of the vortex electromagnetic wave wireless communication system. In particular, in the face of a complex broadband interference environment and when the interference channel state information is unknown, the existing anti-interference technology is difficult to achieve the ideal anti-interference effect. A perception-assisted vortex electromagnetic wave anti-interference method, device and system are provided.

[0009] In order to achieve the above object, the present invention adopts the following technical solutions:

[0010] A first aspect of the present invention provides a sensing-assisted vortex electromagnetic wave anti-interference method, which is applied to a transmitting end and includes the following steps:

[0011] Based on the received interference signal, estimate the location information of the interference source and obtain the interference channel state information;

[0012] Designing a transmit-receive joint phase matrix using interference channel state information, wherein the transmit-receive joint phase matrix includes a phase matrix of a receiving end and a phase matrix of a transmitting end;

[0013] Based on the interference channel state information and the joint phase matrix of transmission and reception, the orthogonality of vortex electromagnetic wave modes is utilized to select L modes that are least affected by interference as carriers for multiplexing transmission of L signals, and power is allocated to the L multiplexed signals to achieve maximum spectrum efficiency under interference.

[0014] Send the signal to the receiving end and decode the mode, restore the signal of each mode, and achieve interference suppression.

[0015] Further, the interference channel state information is obtained, specifically:

[0016] Based on the received interference signal, the Enhanced multi-signal classification (EMUSIC) algorithm is used to estimate the azimuth and elevation angles of the interference source;

[0017] Based on the strength of the interference signal received by different antennas, the received signal strength (RSS) algorithm is used to estimate the distance from the interference source to the antenna center;

[0018] Estimate the location information of the interference source based on the azimuth and elevation angles of the interference source and the distance from the interference source to the center of the antenna;

[0019] Based on the location information of the interference source, interference channel state information is obtained.

[0020] Furthermore, the design of the transmit-receive joint phase matrix is ​​as follows:

[0021] Determine the circulant matrix H of the transceiver channel based on the channel information from the transmitter to the receiver c ;

[0022] Based on the circulant matrix H of the transmit and receive channel c Design the transmit-receive joint phase matrix;

[0023] Based on the joint phase matrix of transmission and reception, the circulant matrix H is adopted c The diagonal matrix W H H c W eliminates inter-mode crosstalk, where W is the phase relationship between the nth element on the transmitting UCA antenna and mode l. ln The inverse discrete Fourier transform (IDFT) matrix is ​​composed of 1≤n≤N; N is the number of array elements of the transmitting UCA antenna; W H Represents the Discrete Fourier Transform (DFT) matrix.

[0024] Furthermore, the circulant matrix H of the transmit and receive channels is c Specifically:

[0025] Perform singular value decomposition on the transmit and receive channel matrix to obtain the circulant matrix H C .

[0026] Furthermore, the circulant matrix H based on the transceiver channelC The design of the transmit-receive joint phase matrix is ​​as follows:

[0027] Determine the relationship between the transmit-receive joint phase matrix and the circulant matrix of the transmit-receive channel; based on the circulant matrix of the transmit-receive channel, obtain the transmit-receive joint phase matrix, and the relationship between the transmit-receive joint phase matrix and the circulant matrix of the transmit-receive channel is:

[0028] H C =W r HW t

[0029] Among them, W r is the phase matrix at the receiving end, W t is the phase matrix of the transmitter, H is the mn The channel matrix from the transmitter to the receiver is composed of mn is the channel vector from the nth array element of the transmitting UCA antenna to the mth array element of the receiving UCA antenna, 1≤m≤M; M is the number of array elements of the receiving UCA antenna.

[0030] Furthermore, the spectrum efficiency can be maximized under interference, specifically:

[0031] Based on the interference channel state information, the modal interference distribution is obtained, and the L modes least affected by interference are selected as carriers for L-channel signal multiplexing transmission to find the power corresponding to each mode under the maximum spectrum efficiency.

[0032] Further, interference suppression is achieved specifically as follows:

[0033] The receiving end uses the DFT matrix to demodulate the signal sent by the transmitting end to obtain the decomposed signal, and then demodulates the decomposed signal to obtain the estimated signal to achieve interference suppression;

[0034] The decomposed signal is as follows:

[0035]

[0036] Among them, Λ H =W H H c W, is the transmission power P of each mode l The diagonal matrix formed by combining; s = [s0,0,…,s l ,0] T is the useful signal s containing the lth row l The vector of (·) T Represents the transpose of a matrix; s j is the interference signal emitted by the interference source; j For h mjThe channel gain from the interference source to the receiving end is composed of; n is the mean value received by the receiving end is 0 and the variance is Additive white Gaussian noise.

[0037] A second aspect of the present invention provides a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, it implements the above-mentioned perception-assisted vortex electromagnetic wave anti-interference method.

[0038] The third aspect of the present invention provides a perception-assisted vortex electromagnetic wave anti-interference device, including a memory and a processor; when the processor calls the computer program or instruction in the memory, the above-mentioned perception-assisted vortex electromagnetic wave anti-interference method is executed.

[0039] A fourth aspect of the present invention provides a sensing-assisted vortex electromagnetic anti-interference system, comprising:

[0040] An interference source location confirmation module is used to estimate the location information of the interference source based on the received interference signal and obtain the interference channel state information;

[0041] An inter-mode interference elimination module is used to design a transmit-receive joint phase matrix using interference channel state information, wherein the transmit-receive joint phase matrix includes a phase matrix of a receiving end and a phase matrix of a transmitting end;

[0042] The intentional interference elimination module is used to select L modes that are least affected by interference as carriers for multiplexing transmission of L signals based on the interference channel state information and the joint phase matrix of transmission and reception, and utilize the orthogonality of the vortex electromagnetic wave modes, and perform power allocation on the L multiplexed signals to achieve maximum spectrum efficiency under interference;

[0043] The signal demodulation module is used to send signals to the receiving end and demodulate them, recover each modal signal, and achieve interference suppression.

[0044] Compared with the prior art, the present invention has the following beneficial effects:

[0045] The present invention discloses a perception-assisted vortex electromagnetic wave anti-interference method. By using EMUSIC combined with RSS algorithm, only one perception receiving end is required to realize accurate estimation of the interference source position, thereby greatly simplifying the system design. In particular, when the number of targets in blind estimation is less than the actual number of targets, the EMUSIC method can still accurately estimate the number of targets and their positions, showing excellent performance. By optimizing mode selection and power allocation, the present invention utilizes the interference channel state information obtained by perception, combined with the orthogonal characteristics between modes, decomposes the interference signal into each mode, and then selects the mode least affected by interference for transmission, thereby minimizing the impact of interference on useful signals. Even in the case of unknown interference channel state information, this method can still significantly improve the anti-interference performance of the communication system, thereby improving the reliability of the communication system. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0047] Figure 1 A structural diagram of a wireless communication system according to an embodiment of the present invention;

[0048] Figure 2 This is a flow chart of the perception-assisted vortex electromagnetic wave anti-interference method of the present invention;

[0049] Figure 3 The figure is a comparison diagram of the spectrum efficiency of the present invention and the existing anti-interference system without perception assistance under different transmission signal-to-noise ratios;

[0050] Figure 4 This is a comparison diagram of spectrum efficiency of the present invention when different power allocation methods are adopted.

[0051] Among them, 1-transmitter; 1.1-transmitting UCA antenna; 1.2-first receiving UCA antenna; 1.3-second receiving UCA antenna; 2-receiving end; 3-interference source; 4-channel; 5-interference signal. DETAILED DESCRIPTION

[0052] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. The components of the embodiments of the present invention described and marked in the drawings here can be arranged and designed in various different configurations.

[0053] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0054] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0055] The present invention is further described in detail below in conjunction with the accompanying drawings:

[0056] See also Figure 1 In the embodiment of the present invention, the wireless communication system includes a transmitter 1, a receiver 2 and an interference source 3. The interference source 3 is a single antenna, which attempts to interrupt the legitimate communication between the transmitter 1 and the receiver 2 by intensively transmitting interference signals. Usually, the interference source 3 is closer to the receiver 2 than the transmitter 1. The transmitter 1 is composed of three coaxial UCA antennas and a single antenna located at the origin, and the three coaxial UCA antennas include a transmitting UCA antenna 1.1, a first receiving UCA antenna 1.2 and a second receiving UCA antenna 1.3; the transmitter 1 simultaneously uses two UCA antennas containing U array elements (i.e., the first receiving UCA antenna 1.2 and the second receiving UCA antenna 1.3) and a single antenna located at the origin to receive the interference signal 5 to detect the position of the interference source 2, and the single antenna is configured at the center of the three coaxial UCA antennas; the transmitting UCA antenna 1.1 contains N array elements to generate multiple orthogonal beams and transmit useful signals to the receiver 2; the receiver 2 is configured with a UCA antenna containing M array elements to receive signals from the transmitter 1 and the interference source 2. In this example, N=M=U is set and the UCA antennas of the transmitter 1 and the receiver 2 are not aligned in parallel. It should be noted that the transmitter and the receiver provided in the present invention are not limited to UCA antennas, and spiral phase plate antennas, new antennas made of metasurface materials, etc. can be applied; in this embodiment, the interference source 2 is a single antenna, but in practical applications, multi-antenna interference sources are also applicable. In this embodiment, the center of the UCA antenna at the transmitter is the coordinate origin, the horizontal axis of the plane where the UCA antenna at the transmitter is located is the x-axis, and it is aligned with the initial antenna array element of the UCA antenna at the transmitter; the y-axis is the axis perpendicular to the x-axis in the plane of the UCA antenna at the transmitter; and the axis perpendicular to the xy plane is the z-axis.

[0057] See also Figure 2 This embodiment discloses a sensing-assisted vortex electromagnetic wave anti-interference method, comprising the following steps:

[0058] S1: Estimation of the sending signal and the receiving and transmitting channel at the transmitter:

[0059] In order to effectively deal with complex interference environments, multiple orthogonal beams are generated by designing the transmission signal to ensure the orthogonality between different modes and effectively guarantee the signal transmission quality in complex interference environments. The details are as follows:

[0060] S101, orthogonal beam formation: In order to generate multiple orthogonal beams on the UCA antenna, the N array elements on the transmitting UCA antenna of the transmitting end are fed with the same input modulation signal, and the orthogonality between these signals is ensured by phase difference. To achieve this purpose, the present invention uses an IDFT (Inverse discrete Fourier transform) sequence to modulate each antenna. The IDFT sequence is:

[0061]

[0062] S102, mode hopping design: The present invention adopts a mode hopping strategy when sending signals. In the mode hopping strategy, the mode of the sent signal is not fixed, but dynamically switched according to the perception result of the interference source position, so as to effectively avoid the interference of the interference source. The present invention defines the number of modes L and the mode set L. The transmitting UCA antenna of the transmitting end activates these modes according to the index information to transmit valid signals.

[0063] S103, based on the designs of S101 and S102, the transmission signal of the nth array element of the transmitting UCA antenna at the transmitting end can be expressed as:

[0064]

[0065] It can be seen that the transmitted signal x n It can be expressed as a weighted sum of multiple modal signals, where the weights are determined by the elements of the IDFT matrix and the power of each mode.

[0066] If the signals of all antennas are expressed as vectors, the transmit signal vector x of the entire UCA array can be expressed as follows:

[0067] x=WPs

[0068] S104, transmit and receive channel estimation: perform channel estimation on the channel between the transmitter and the receiver. The purpose of channel estimation is to measure the attenuation, delay, noise and other factors of the transmitted signal after passing through the channel. In order to perform transmit and receive channel estimation, the present invention uses the Zadoff-Chu (ZC) sequence as a pilot signal, which has good autocorrelation and cross-correlation characteristics. The present invention is not limited to estimating the channel through the pilot sequence ZC when performing channel estimation. Methods such as least squares method, minimum mean square error (MMSE), and blind channel estimation can all be used to estimate the channel. In order to estimate the channel from the transmitter to the receiver, a pilot matrix G is transmitted from the transmitter to the receiver, where G is a matrix composed of the ZC sequence g ln Composition, g ln Located in the nth row and lth column, it represents the ZC sequence of mode l of the nth array element.

[0069] g ln Described as:

[0070]

[0071] in,(·) N represents modular operation, k is a positive integer coprime with N, and g is any positive integer.

[0072] S2: Based on the interference signal received by the transmitter, estimate the interference source location information and obtain the interference channel state information.

[0073] S201, the interference signal y received by the first receiving UCA antenna of the transmitting end js It is expressed as follows:

[0074] y js =h js s j +n s

[0075] Among them, h js =[h 1j, h 2j, …,h uj ,…,h Uj ] T represents the channel gain vector from the interference source to the first receiving UCA of the transmitter; h uj is the channel gain between the interference source and the receiving UCA element u (1≤u≤U), n s The mean value received by the first receiving UCA antenna at the transmitting end is 0 and the variance is σ 2 Additive Gaussian white noise. h js Contains the spatial position information of the interference source relative to the transmitter: azimuth angle α j , pitch angle φj and the relative distance d js .

[0076] S202. Estimate the azimuth angle α using the EMUSIC algorithm based on the interference signal received at the transmitting end j and the elevation angle φ j , and estimate the relative distance d from the interference source to the center of the transmitting end antenna using the RSS algorithm js :

[0077] Estimate the azimuth angle α using the EMUSIC algorithm j and the elevation angle φ j , specifically:

[0078] (a) Based on the received interference signal y js , h js The covariance matrix of is expressed as follows:

[0079]

[0080] where is the transmission power of the interference signal, I U is the identity matrix of dimension U×U, (·) H represents the conjugate transpose of the matrix.

[0081] (b) Perform eigenvalue decomposition on , and it can be re-expressed as:

[0082]

[0083] where μ1≥μ2…≥μ U is the eigenvalue of, Ω = diag{μ1,…,μ U} is a diagonal matrix, V = [v1,v2,…,v U is the eigenmatrix composed of the eigenvectors v u corresponding to μ u u

[0084] (c) Perform eigenvalue decomposition on , decompose it into the signal space and the noise space. By sorting the magnitudes of the eigenvalues, select the eigenvectors corresponding to the first P (1≤P<U) larger eigenvalues to form the signal space, where P is the estimated number of signal sources; the eigenvectors corresponding to the remaining U - P smaller eigenvalues form the noise space. Therefore, The eigenvalue matrix of can be re-expressed as:

[0085] ​

[0086] Where Ω j and Ω n are diagonal matrices consisting of larger P eigenvalues ​​and smaller UP eigenvalues, respectively, V j =[v1,…,v P ] represents the signal space, V n =[v P+1 ,…,v U-P ] represents the noise space.

[0087] (d) Based on the signal and noise space vectors of step (c), the noise space is reconstructed, specifically:

[0088]

[0089] Then the spatial spectrum function is used to estimate the azimuth angle α of the interference source j and the pitch angle φ j , the spatial spectrum function F(θ,φ) is:

[0090]

[0091] Where b represents the position vector, which is described as:

[0092] λ is the carrier wavelength, R s1 is the radius of the first receiving UCA antenna at the transmitting end; α s is the initial azimuth of the transmitting UCA antenna; α∈[0,2π] is the azimuth; φ is the angle between the z-axis and the line connecting the transmitting UCA center and the receiving UCA center; θ is the angle between the projection of the line from the transmitting UCA antenna center to the receiving UCA antenna center on the transmitting UCA and the x-axis.

[0093] Finally, by searching for the peak of the spatial spectrum function, the azimuth angle α of the interference source can be estimated. j and the pitch angle φ j .

[0094] The relative distance d from the interference source to the center of the UCA antenna at the transmitting end is estimated using the RSS algorithm. js , specifically:

[0095] (a) The transmitter measures the received signal strength by setting up three UCA antennas at different locations, namely, the first receiving UCA antenna, the second receiving UCA antenna, and the single antenna at the origin of the transmitter. The RSS value S of the first receiving UCA antenna is outer1 , the RSS value S of the second receiving UCA antenna outer2 and S center The RSS values ​​of the single antenna at the origin of the transmitter are:

[0096]

[0097] Where c1 = (βλ / (4π)) 2 , R s2 is the radius of the second receiving UCA antenna at the transmitting end; β represents the relevant parameters, including the attenuation and phase rotation caused by the antenna and the directional patterns on both sides of it.

[0098] (b) Based on three RSS values ​​S outer1 , S outer2 and S center , estimate the relative distance d from the interference source to the center of the UCA antenna at the transmitter js It is expressed as follows:

[0099]

[0100] The expression of C2 is:

[0101]

[0102] The estimated result based on the interference source location (d js ,α j ,φ j ) to obtain the interference channel state information from the interference source to the receiving end.

[0103] S3: Inter-mode crosstalk elimination: Based on the channel state information from the transmitter to the receiver estimated in S104, a joint transmit-receive phase matrix is ​​designed to eliminate inter-mode crosstalk; the joint transmit-receive phase matrix includes a phase matrix of the receiver and a phase matrix of the transmitter.

[0104] S301, construct circulant matrix H c :

[0105] Perform singular value decomposition (SVD) on the transmit and receive channel H to obtain H = S H D H V H , where S H and V H are all unitary matrices, D H is a diagonal matrix containing the singular values ​​of H. According to the characteristics of IDFT, the circulant matrix H c The first line of can be expressed as:

[0106]

[0107] in, represents the channel characteristics under the nth mode, diag(D H ) is given by the matrix D HThe diagonal matrix consists of the diagonal elements of . According to H c Cyclic characteristics, H c It can be expressed as:

[0108]

[0109] S302, determine the receiving end phase matrix W r and the transmitting end phase matrix W t :

[0110] Based on the circulant matrix H of the transceiver channel calculated in S301 c , performing SVD decomposition on it can obtain the unitary matrix and The specific expressions are as follows:

[0111]

[0112] in, It contains H c Diagonal matrix of singular values.

[0113] The relationship between the designed transmit-receive joint phase matrix and the circulant matrix of the transmit-receive channel is: c =W r HW t , so the joint phase matrix W r and W t for:

[0114]

[0115] S303, based on the joint phase matrix of transmission and reception, using the diagonal matrix W H H c y eliminates the inter-mode crosstalk of the transmitted signal, and the signal received by the receiving end is:

[0116] y=W r HW t WPs+W r h j s j +W r n

[0117] S4, intentional interference elimination: Based on the interference channel state information and the joint phase matrix of transmission and reception, the orthogonality of the vortex electromagnetic wave modes is utilized to select L modes that are least affected by interference as the carriers for L-channel signal multiplexing transmission; the transmitter allocates power to the L-channel multiplexed signals to maximize the spectrum efficiency under interference.

[0118] S401, based on W r and interference channel status information, using the orthogonality of vortex electromagnetic wave modes, the transmitter performs WH W r h j Calculate and decompose the interference into each mode, and select L modes least affected by the interference as the carriers for L-channel signal multiplexing transmission.

[0119] S402: The transmitting end distributes power to the L multiplexed signals to maximize spectrum efficiency under interference.

[0120] The present invention maximizes the capacity upper bound C by adjusting the transmission power of each mode. OS , so as to find the optimal power allocation scheme to maximize the spectrum efficiency of the system in the presence of interference, thereby improving the anti-interference performance of the system.

[0121] The upper limit of the capacity to resist intentional interference C OS It is expressed as:

[0122]

[0123] in, represents the number of combinations of activated modes, is the floor function, γ l is the received signal to interference plus noise ratio (SINR) of mode l.

[0124] In order to maximize the spectrum efficiency under intentional interference, the capacity upper bound C OS The maximum spectrum efficiency maximization problem can be expressed as P1, as follows:

[0125]

[0126] in, P t is the total transmission power, P th It is the minimum allocated power threshold.

[0127] S403, the signal transmission process from the sending end to the receiving end can be expressed as:

[0128] y=H c WP+W r h j s j +W r n

[0129] S404, at the receiving end, a DFT (Discrete Fourier Transform) matrix is ​​used to perform mode decomposition to obtain a decomposed signal The specific expression is as follows:

[0130]

[0131] Among them, Λ H =W H H c W is the diagonal matrix after DFT processing.

[0132] After demodulating the demodulated signal, we get the estimated signal It is expressed as:

[0133]

[0134] Among them, the lth row of s corresponds to the useful signal s l , and the other positions are 0. This means that although there are multiple possible modes, the useful signal actually transmitted is only in L specific modes, and there is no transmission signal in other modes. Therefore, it can be considered that the modal transmission mode of the estimated signal is the modal transmission mode that is least affected by interference.

[0135] According to the mode index information used for useful signal transmission in S102, since the transmitting end selects L modes least affected by interference in the mode set L as the carrier to transmit the corresponding index information a t =[0,1,…,0,1] T , where 1 represents the activated mode (i.e. the mode with small interference effect), and the other elements are set to 0. Then the useful signal received by the receiver is:

[0136]

[0137] In order to further illustrate the advantages of the present invention, the following experiments can be used to further illustrate:

[0138] This embodiment sets the carrier frequency to 2.4 GHz, the UCA radius of the transmitting end to λ, the UCA radius of the receiving end to 4λ, the first receiving UCA radius of the transmitting end to 4λ, the second receiving UCA radius of the transmitting end to 6λ, the interference source coordinates to (5,20,35) m, and the transmission interference-noise ratio to 20 dB. The simulation conditions simulate the interference source position estimation based on the EMUSIC joint RSS algorithm proposed in the present invention, analyzes the spectral efficiency of the anti-interference scheme under perception-assisted and non-perception-assisted conditions, and the influence of different power allocation methods on the spectral efficiency of the anti-interference scheme. Figure 3 The estimated interference source position is compared with the actual position, and it is found that the estimated interference source position is very close to the actual position, which verifies the effectiveness of the EMUSIC combined RSS algorithm proposed in the present invention. In the case of traditional mode selection scheme without using perception assistance, there is a certain probability that the L worst modes are selected for L-channel multiplexing transmission of the signal. Therefore, the spectrum efficiency is low and performs at an average level. Figure 3 The spectral efficiency of the anti-interference scheme with and without sensory assistance is also compared. In the simulation, L=4 and N=16 are set. It can be observed that the sensory assisted anti-interference scheme proposed in the present invention has higher spectral efficiency than that without sensory assistance. This is because the sensing capability allows the proposed scheme to dynamically select the mode with the least interference impact and the highest signal-to-noise ratio, thereby effectively mitigating interference attacks.

[0139] Figure 4 The spectral efficiency of the anti-interference scheme proposed in the present invention under different N and power allocation methods is compared, where L is set to 4. It can be seen that the spectral efficiency of the present invention is always higher than the spectral efficiency under equal power allocation. In addition, under a fixed L, increasing N will improve the spectral efficiency of the wireless communication system, mainly because increasing N will increase the index information. However, due to the hollow divergence of the OAM beam, the improvement of the spectral efficiency is small.

[0140] It can be seen that the perception-assisted anti-interference method proposed in the present invention can accurately locate the interference source with the help of the EMUSIC combined with the RSS algorithm, and improve the anti-interference performance of the wireless communication system under deliberate interference, meeting the requirements of modern communications.

[0141] An embodiment of the present invention provides a sensing-assisted vortex electromagnetic anti-interference system, comprising:

[0142] An interference source location confirmation module is used to estimate the location information of the interference source based on the received interference signal and obtain the interference channel state information;

[0143] An inter-mode interference elimination module is used to design a transmit-receive joint phase matrix using interference channel state information, wherein the transmit-receive joint phase matrix includes a phase matrix of a receiving end and a phase matrix of a transmitting end;

[0144] The intentional interference elimination module is used to select L modes that are least affected by interference as carriers for multiplexing transmission of L signals based on the interference channel state information and the joint phase matrix of transmission and reception, and utilize the orthogonality of the vortex electromagnetic wave modes, and perform power allocation on the L multiplexed signals to achieve maximum spectrum efficiency under interference;

[0145] The signal demodulation module is used to send signals to the receiving end and demodulate them, recover each modal signal, and achieve interference suppression.

[0146] An embodiment of the present invention provides a perception-assisted vortex electromagnetic wave anti-interference device, including a memory and a processor; when the processor calls a computer program or instruction in the memory, the above-mentioned perception-assisted vortex electromagnetic wave anti-interference method is executed.

[0147] One embodiment of the present invention provides a computer-readable storage medium having a computer program stored thereon. When the program is executed by a processor, a perception-assisted vortex electromagnetic wave anti-interference method can be implemented. The computer-readable storage medium is a memory device in a terminal device for storing programs and data. It is understandable that the computer-readable storage medium herein may include both a built-in storage medium in a terminal device and an extended storage medium supported by the terminal device. It may be any tangible medium containing or storing a program, which may be used by or in combination with an instruction execution system, device or device. The computer-readable storage medium provides a storage space that stores the operating system of the terminal. In addition, one or more instructions suitable for being loaded and executed by a processor are also stored in the storage space. These instructions may be one or more computer programs (including program codes). It should be noted that more specific examples of computer-readable storage media herein (a non-exhaustive list) include: an electrical connection with one or more conductors, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. Computer-readable storage media also include data signals propagated in baseband or as part of a carrier wave, which carry readable program code. Such propagated data signals can take a variety of forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. The readable storage medium can also be any readable medium other than a readable storage medium, which can send, propagate or transmit a program for use by or in conjunction with an instruction execution system, device or device. The program code contained on the readable storage medium can be transmitted using any appropriate medium, including but not limited to wireless, wired, optical cable, RF, etc., or any suitable combination of the above.

[0148] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A sensing-assisted vortex electromagnetic wave anti-interference method, characterized in that: Applied to the sending end, it includes the following steps: Based on the received interference signal, estimate the location information of the interference source and obtain the interference channel state information; Designing a transmit-receive joint phase matrix using interference channel state information, wherein the transmit-receive joint phase matrix includes a phase matrix of a receiving end and a phase matrix of a transmitting end; Based on the interference channel state information and the joint phase matrix of transmission and reception, the orthogonality of vortex electromagnetic wave modes is utilized to select L modes that are least affected by interference as carriers for multiplexing transmission of L signals, and power is allocated to the L multiplexed signals to achieve maximum spectrum efficiency under interference. Send the signal to the receiving end and decode the mode, restore the signal of each mode, and achieve interference suppression.

2. The perception-assisted vortex electromagnetic wave anti-interference method according to claim 1 is characterized in that: Obtain interference channel status information, specifically: Based on the received interference signal, the EMUSIC algorithm is used to estimate the azimuth and elevation angles of the interference source; Based on the strength of the interference signal received by different antennas, the RSS algorithm is used to estimate the distance from the interference source to the center of the antenna; Estimate the location information of the interference source based on the azimuth and elevation angles of the interference source and the distance from the interference source to the center of the antenna; Based on the location information of the interference source, interference channel state information is obtained.

3. The perception-assisted vortex electromagnetic wave anti-interference method according to claim 1 is characterized in that: The design of the transmit-receive joint phase matrix is ​​as follows: Determine the circulant matrix H of the transceiver channel based on the channel information from the transmitter to the receiver c ; Based on the circulant matrix H of the transmit and receive channel c Design the transmit-receive joint phase matrix; Based on the joint phase matrix of transmission and reception, the circulant matrix H is adopted c The diagonal matrix W G H c W eliminates inter-mode crosstalk, where W is the phase relationship between the nth element on the transmitting UCA antenna and mode l. ln The IDFT matrix is ​​composed of 1≤n≤N; N is the number of array elements of the transmitting UCA antenna; W H represents the DFT matrix.

4. The perception-assisted vortex electromagnetic wave anti-interference method according to claim 3 is characterized in that: The circulant matrix H of the transmit and receive channel c Specifically: Perform singular value decomposition on the transmit and receive channel matrix to obtain the circulant matrix H c .

5. The perception-assisted vortex electromagnetic wave anti-interference method according to claim 3 is characterized in that: The circulant matrix H based on the transceiver channel c The design of the transmit-receive joint phase matrix is ​​as follows: Determine the relationship between the transmit-receive joint phase matrix and the circulant matrix of the transmit-receive channel; obtain the transmit-receive joint phase matrix based on the circulant matrix of the transmit-receive channel; the relationship between the transmit-receive joint phase matrix and the circulant matrix of the transmit-receive channel is: H c =W r HW t Among them, W r is the phase matrix at the receiving end, W t is the phase matrix of the transmitter, H is the mn The channel matrix from the transmitter to the receiver is composed of mn is the channel vector from the nth array element of the transmitting UCA antenna to the mth array element of the receiving UCA antenna, 1≤m≤M; M is the number of array elements of the receiving UCA antenna.

6. The perception-assisted vortex electromagnetic wave anti-interference method according to claim 1, characterized in that: Maximize spectrum efficiency under interference, specifically: Based on the interference channel state information, the modal interference distribution is obtained, and the L modes least affected by interference are selected as carriers for L-channel signal multiplexing transmission to find the power corresponding to each mode under the maximum spectrum efficiency.

7. The perception-assisted vortex electromagnetic wave anti-interference method according to claim 1 is characterized in that: The specific implementation of interference suppression is as follows: The receiving end uses the DFT matrix to demodulate the signal sent by the transmitting end to obtain the decomposed signal, and then demodulates the decomposed signal to obtain the estimated signal to achieve interference suppression; The decomposed signal is as follows: Among them, Λ H =W H H c W, W r is the phase matrix at the receiving end, W H represents the DFT matrix; is the transmission power P of each mode l The diagonal matrix formed by combining; s = [s0,0,…,s l ,0] T is the useful signal s containing the lth row l The vector of (·) T Represents the transpose of a matrix; s j is the interference signal emitted by the interference source; j For h mj The channel gain from the interference source to the receiving end is composed of; n is the mean value received by the receiving end is 0 and the variance is Additive white Gaussian noise.

8. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the perception-assisted vortex electromagnetic wave anti-interference method according to any one of claims 1 to 7 is implemented.

9. A sensing-assisted vortex electromagnetic wave anti-interference device, characterized in that: It comprises a memory and a processor; when the processor calls the computer program or instruction in the memory, it executes the perception-assisted vortex electromagnetic wave anti-interference method described in any one of claims 1-7.

10. A sensing-assisted vortex electromagnetic anti-interference system, characterized in that: include: An interference source location confirmation module is used to estimate the location information of the interference source based on the received interference signal and obtain the interference channel state information; An inter-mode interference elimination module is used to design a transmit-receive joint phase matrix using interference channel state information, wherein the transmit-receive joint phase matrix includes a phase matrix of a receiving end and a phase matrix of a transmitting end; The intentional interference elimination module is used to select L modes that are least affected by interference as carriers for multiplexing transmission of L signals based on the interference channel state information and the joint phase matrix of transmission and reception, and utilize the orthogonality of the vortex electromagnetic wave modes, and perform power allocation on the L multiplexed signals to achieve maximum spectrum efficiency under interference; The signal demodulation module is used to send signals to the receiving end and demodulate them, recover each modal signal, and achieve interference suppression.

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