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

Abstract

The application discloses a kind of perception-assisted vortex electromagnetic wave anti-interference method, device and system, based on the interference signal received by sending end, using EMUSIC joint RSS algorithm, the position information of interference source is estimated, and interference channel state information is obtained accordingly;Based on the complete channel state information known by transceiver end, design transceiver joint phase matrix, eliminate intermodular interference;According to the estimated interference channel state information, the interference signal is decomposed to each mode on sending end, select the L mode that is least affected by interference as the carrier of L-way signal multiplexing transmission;Sending end carries out power allocation to L-way multiplexing signal, to realize maximum spectral efficiency under interference;The signal received by receiving end is demodulated, restores each mode signal, realizes interference suppression;Solve the problem that vortex electromagnetic wave communication anti-interference effect is not good under the condition that interference channel state information is unknown, improve the reliability of communication system.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of wireless communication, and relates to a perception-assisted vortex electromagnetic wave anti-interference method, device and system. BACKGROUND

[0002] Wireless communication systems play a vital role in modern communication networks, however, due to the openness and broadcast nature of its channel, the system is extremely vulnerable to malicious jamming attacks, resulting in a significant decline in communication quality. In order to cope with this challenge, scholars in academia and industry have carried out in-depth research on the improvement of the anti-interference ability of wireless communication, in order to guarantee the communication quality while improving the information transmission efficiency.

[0003] At present, frequency hopping technology is the mainstream technology in the field of wireless communication anti-interference. This technology switches according to the pre-set frequency hopping pattern through the rapid change of the carrier frequency between the legal sending end and the receiving end, thereby reducing the probability of the legal signal being jammed. However, the anti-interference ability of frequency hopping technology is not satisfactory when facing the same frequency interference attack. Therefore, exploring new anti-interference technology to realize the significant improvement of the anti-interference ability of wireless communication system under the same frequency interference has become an urgent need of current research.

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

[0005] In order to further enhance the anti-interference ability of OAM wireless communication system, the academia has proposed a variety of innovative solutions. For example, by introducing frequency agile signals to enhance the anti-interference performance of OAM radar system, the jumping characteristics of frequency agile signals are used to increase the difficulty of interference signal parameter prediction, and the problem of target azimuth information acquisition is solved by using compressed sensing algorithm. In addition, a multi-mode vortex radar anti-interference scheme based on waveform diversity is also proposed, which combines OAM mode and waveform diversity technology to expand the signal space dimension of traditional radar system, in order to enhance the ability to identify and suppress digital radio frequency memory interference.

[0006] Another innovative anti-jamming scheme is the vortex electromagnetic wave mode hopping anti-jamming technology. This technology quickly switches the vortex electromagnetic wave mode through the pre-shared mode hopping sequence of the sending end and the receiving end, reducing the probability of the own signal being jammed. This method expands the anti-jamming method from the traditional frequency domain to the two-dimensional mode-frequency domain, enriches the diversity of the cooperative signal transmission carrier, and significantly reduces the probability of being jammed.

[0007] However, although the vortex electromagnetic wave anti-jamming technology has great potential, it still faces some challenges in practical application. When the sending end and the receiving end are not parallelly aligned, the orthogonality between different modes will be destroyed, resulting in a decrease in the anti-jamming performance of the vortex electromagnetic wave wireless communication system. Especially in the case of facing a complex broadband jamming environment and unknown interference channel state information (CSI), the existing anti-jamming technology is difficult to achieve the ideal anti-jamming effect. Therefore, how to fully utilize the orthogonality between vortex electromagnetic wave modes in the case of unknown interference channel state information to improve the anti-jamming capability of the wireless communication system has become a technical problem that needs to be solved urgently. SUMMARY

[0008] The purpose of the present application is to solve the technical problem in the prior art that when the sending end and the receiving end are not parallelly aligned, the orthogonality between different modes will be destroyed, resulting in a decrease in the anti-jamming performance of the vortex electromagnetic wave wireless communication system. Especially in the case of facing a complex broadband jamming environment and unknown interference channel state information (CSI), the existing anti-jamming technology is difficult to achieve the ideal anti-jamming effect. The present application provides a perception-assisted vortex electromagnetic wave anti-jamming method, device and system.

[0009] To achieve the above-mentioned purpose, the present application adopts the following technical solutions:

[0010] The present application provides a perception-assisted vortex electromagnetic wave anti-jamming method in the first aspect, applied to a sending end, comprising the following steps:

[0011] Based on the received interference signal, the position information of the interference source is estimated to obtain the interference channel state information;

[0012] A transceiver joint phase matrix is designed using the interference channel state information, wherein the transceiver joint phase matrix includes a phase matrix of the receiving end and a phase matrix of the sending end;

[0013] Based on the interference channel state information and the transceiver joint phase matrix, the vortex electromagnetic wave mode orthogonality is used to select L modes with the least interference as carriers for multiplexing transmission of L signals, and power allocation is performed on the L multiplexed signals to maximize the spectral efficiency under interference;

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

[0015] Furthermore, the interference channel status 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 antenna center;

[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 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 transceiver channel 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 transceiver joint phase matrix is specifically:

[0027] The relationship between the transceiver joint phase matrix and the circulant matrix of the transceiver channel is determined; based on the circulant matrix of the transceiver channel, the transceiver joint phase matrix is obtained, and the relationship between the transceiver joint phase matrix and the circulant matrix of the transceiver channel is:

[0028] H C =W r HW t

[0029] Wherein, W r is the phase matrix of the receiving end, W t is the phase matrix of the sending end, H is the channel matrix from the sending end to the receiving end composed of h mn , h mn is the channel vector from the nth element of the sending UCA antenna to the mth element of the receiving UCA antenna, 1≤m≤M; M is the number of elements of the receiving UCA antenna.

[0030] Further, the maximum spectrum efficiency under interference is realized, specifically:

[0031] Based on the interference channel state information, the modal interference distribution is obtained, the L modes with the least interference influence are selected as the carriers, L-way signal multiplexing transmission is carried out, and the power corresponding to each mode under the maximum spectrum efficiency is found.

[0032] Further, the interference suppression is specifically:

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

[0034] The decomposed signal is as follows:

[0035]

[0036] Wherein, Λ H =W H H c W, is a diagonal matrix composed of the transmission power P l of each mode; s=[s0,0,…,s l ,0] T is a vector containing the useful signal s l of the lth row, (·) T represents the transpose of the matrix; s j is the interference signal transmitted by the interference source; h j is composed of h mja channel gain of the interference source to the receiving end; n is a mean value of 0 and a variance of additive white Gaussian noise.

[0037] The second aspect of the present application provides a computer readable storage medium, the computer readable storage medium stores a computer program, the computer program is executed by a processor to realize the above-mentioned perception-assisted vortex electromagnetic wave anti-interference method.

[0038] The third aspect of the present application provides a perception-assisted vortex electromagnetic wave anti-interference device, comprising 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] The fourth aspect of the present application provides a perception-assisted vortex electromagnetic anti-interference system, comprising:

[0040] An interference source position confirmation module is configured to estimate the position 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 configured to design a transceiver joint phase matrix using the interference channel state information, wherein the transceiver joint phase matrix comprises a phase matrix of the receiving end and a phase matrix of the transmitting end.

[0042] A deliberate interference elimination module is configured to select L modes with the least interference as carriers for multiplexing transmission of L signals using the orthogonality of vortex electromagnetic wave modes based on the interference channel state information and the transceiver joint phase matrix, and perform power allocation on the L multiplexed signals to maximize the spectral efficiency under interference.

[0043] A signal demodulation module is configured to send signals to the receiving end and demodulate the signals to recover each mode signal, thereby realizing interference suppression.

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

[0045] The application discloses a perception-assisted vortex electromagnetic wave anti-interference method, utilizes an EMUSIC joint RSS algorithm, and only needs one perception receiving end to realize accurate estimation of the position of an interference source, so that the system design is greatly simplified. In particular, in the case that the target number of blind estimation is less than the actual target number, the EMUSIC method can still accurately estimate the target number and estimate the position, and excellent performance is exhibited. By optimizing mode selection and power distribution, the application utilizes interference channel state information obtained by perception, combines the orthogonal characteristics among modes, decomposes interference signals onto each mode, then selects a mode with the least interference influence for transmission, so that the influence of interference on useful signals is maximally reduced. Even in the case that the interference channel state information is unknown, the method can still significantly improve the anti-interference performance of a communication system, and further improve the reliability of the communication system. BRIEF DESCRIPTION OF DRAWINGS

[0046] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor.

[0047] Figure 1 The figure is a structure diagram of a wireless communication system of the embodiment of the present application.

[0048] Figure 2 The figure is a flowchart of the perception-assisted vortex electromagnetic wave anti-interference method of the present application.

[0049] Figure 3 The figure is a spectrum efficiency comparison diagram of the present application and the existing non-perception-assisted anti-interference system under different transmission signal-to-noise ratios.

[0050] Figure 4 The figure is a spectrum efficiency comparison diagram of the present application under different power distribution methods.

[0051] Among them, 1 is a sending end, 1.1 is a sending UCA antenna, 1.2 is a first receiving UCA antenna, 1.3 is a second receiving UCA antenna, 2 is a receiving end, 3 is an interference source, 4 is a channel, and 5 is an interference signal. DETAILED DESCRIPTION

[0052] In order to make the purpose, technical solutions and advantages of the embodiments of the present application more clear, the following will combine the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are some embodiments of the present application, not all embodiments. The components of the embodiments of the present application described and indicated in the drawings here can be arranged and designed in various different configurations.

[0053] Therefore, the following detailed description of the embodiments of the application provided in the drawings is not intended to limit the scope of the application claimed, but merely represents selected embodiments of the application. Based on the embodiments in the application, all other embodiments obtained by those of ordinary skill in the art without creative labor are within the scope of protection of the application.

[0054] It should be noted that similar reference numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0055] The application will be further described in detail below in conjunction with the drawings:

[0056] Referring to Figure 1 , the wireless communication system in the embodiment of the application includes a sending end 1, a receiving end 2 and an interference source 3. The interference source 3 is a single antenna, which attempts to interrupt the legal communication between the sending end 1 and the receiving end 2 by densely transmitting interference signals. Generally, the interference source 3 is closer to the receiving end 2 than the sending end 1. The sending end 1 is composed of three coaxial UCA antennas and a single antenna at the origin, the three coaxial UCA antennas including a sending UCA antenna 1.1, a first receiving UCA antenna 1.2 and a second receiving UCA antenna 1.3; the sending end 1 simultaneously receives interference signals 5 by using two UCA antennas containing U elements (i.e. the first receiving UCA antenna 1.2 and the second receiving UCA antenna 1.3) and a single antenna at the origin to detect the position of the interference source 2, the single antenna being arranged at the center of the three coaxial UCA antennas; the sending UCA antenna 1.1 contains N elements to generate a plurality of orthogonal beams to transmit useful signals to the receiving end 2; the receiving end 2 is arranged with a UCA antenna containing M elements to receive signals from the sending end 1 and the interference source 2. In this example, N = M = U and the UCA antennas of the sending end 1 and the receiving end 2 are not parallelly aligned. It should be noted that the sending end and the receiving end given in the application are not limited to UCA antennas, and spiral phase plate antennas, super surface material new antennas, etc. can also be applied; the interference source 2 in this embodiment is a single antenna, but in actual application, a multi-antenna interference source is also applicable. In this embodiment, the center of the sending end UCA antenna is taken as the coordinate origin, the horizontal axis of the plane where the sending end UCA antenna is located is taken as the x-axis, and the initial antenna element of the sending end UCA antenna is aligned; the y-axis is the axis perpendicular to the x-axis in the sending end UCA plane; and the z-axis is the axis perpendicular to the x-y plane.

[0057] Referring to Figure 2 , the embodiment discloses a perception-assisted vortex electromagnetic wave anti-interference method, which comprises the following steps:

[0058] S1: estimation of sending signals of the sending end and a transceiving channel:

[0059] In order to effectively cope with the complex interference environment, multiple orthogonal beams are generated by designing the transmitted signal to ensure the orthogonality between different modes, and to ensure that the signal transmission quality can be effectively guaranteed in a complex interference environment. The specific implementation is as follows:

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

[0061]

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

[0063] S103, Based on the design of S101 and S102, the transmitted signal of the nth element of the transmitting UCA antenna of the transmitting end can be represented as:

[0064]

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

[0066] The signals of all antennas are represented in vector form, and the transmitted signal vector x of the entire UCA array can be represented as follows:

[0067] x=WPs

[0068] S104, transceiver channel estimation: channel estimation is performed on the channel between the transmitting end and the receiving end. The purpose of channel estimation is to measure the attenuation, time delay, noise and other factors of the transmitted signal after passing through the channel. In order to perform transceiver channel estimation, the present application uses a Zadoff-Chu (ZC) sequence as a pilot signal, which has good autocorrelation and cross-correlation characteristics. The present application is not limited to estimating the channel by the pilot sequence ZC when performing channel estimation. Least squares, minimum mean square error (MMSE), blind channel estimation and other methods can be used to estimate the channel. In order to estimate the channel from the transmitting end to the receiving end, a pilot matrix G is transmitted from the transmitting end to the receiving end, where G is composed of a ZC sequence g ln ln Located in the nth row and the first column, represents the ZC sequence of the nth element of the mode 1.

[0069] ln Is described as:

[0070]

[0071] Where (·) N Indicates the modulo 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 transmitting end, estimate the interference source position information and obtain the interference channel state information.

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

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

[0075] Where h js = [h 1j, h 2j, …,h uj ,…,h Uj ] T Represents the channel gain vector of the interference source to the first receiving UCA of the transmitting end; h uj Is the channel gain between the interference source and the u-th (1≤u≤U) element of the receiving UCA, n s Is the additive white Gaussian noise received by the first receiving UCA antenna of the transmitting end with a mean of 0 and a variance of σ 2 h js Contains the spatial position information of the interference source relative to the transmitting end: azimuth angle α j , elevation angle φ​​j and relative distance d js .

[0076] S202, based on the received interference signal at the sending end, the azimuth angle a is estimated by using EMUSIC algorithm j and the elevation angle f j , the relative distance d of the interference source to the center of the antenna of the sending end is estimated by using RSS algorithm js :

[0077] The azimuth angle a is estimated by using EMUSIC algorithm j and the elevation angle f j , specifically:

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

[0079]

[0080] wherein, is the transmission power of the interference signal, I U is a unit matrix with dimension UxU, (·) H denotes the conjugate transpose of the matrix.

[0081] (b) eigenvalue decomposition is performed on , and can be denoted as:

[0082]

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

[0084] (c) eigenvalue decomposition is performed on , which is decomposed into a signal space and a noise space. By sorting the eigenvalues, the eigenvalues corresponding to the first P(1≤P<U) larger eigenvalues are selected to form the signal space, wherein P is the number of estimated signal sources; the eigenvalues corresponding to the remaining U-P smaller eigenvalues form the noise space. Therefore, the eigenvalue matrix of

[0085] ​

[0086] where Ω j and Ω n are diagonal matrices composed of the larger P eigenvalues and the smaller U-P 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), reconstruct the noise space, specifically:

[0088]

[0089] Then use the spatial spectrum function to estimate the azimuth angle a j and the elevation angle f j of the interference source, and the spatial spectrum function F(0, f) is:

[0090]

[0091] where b represents the position vector, described as:

[0092] where l is the carrier wavelength, R s1 is the radius of the first receiving UCA antenna of the sending end; a s is the initial azimuth angle of the UCA antenna of the sending end; a e [0, 2p] is the azimuth angle; f is the angle between the z-axis and the line connecting the center of the transmitting UCA and the center of the receiving UCA; 0 is the angle between the line projected on the transmitting UCA and the x-axis.

[0093] Finally, by searching the peak value of the spatial spectrum function, the azimuth angle a j and the elevation angle f j of the interference source can be estimated.

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

[0095] (a) The sending end measures the received signal strength by setting three UCA antennas at different positions, i.e., through the first receiving UCA antenna, the second receiving UCA antenna, and the single antenna at the origin of the sending end. The RSS value S outer1 of the first receiving UCA antenna, the RSS value S outer2 of the second receiving UCA antenna, and the RSS value S center of the single antenna at the origin of the sending end are respectively:

[0096]

[0097] where c1=(βλ / (4π)) 2 , R s2 is the radius of the second receive UCA antenna at the transmitter; β represents relevant parameters including attenuation and phase rotation caused by the antenna and its directional pattern on both sides.

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

[0099]

[0100] where the expression of C2 is:

[0101]

[0102] Based on the estimation results of the interference source position (d js , α j , φ j ), obtain the interference channel state information from the interference source to the receiver.

[0103] S3: Intermodal crosstalk cancellation: based on the channel state information from the transmitter to the receiver estimated in S104, design a transceiver joint phase matrix to cancel the intermodal crosstalk; the transceiver joint phase matrix includes the phase matrix of the receiver and the phase matrix of the transmitter.

[0104] S301, construct a circulant matrix H c :

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

[0106]

[0107] where, represents the channel characteristics under the nth mode, and diag(D H ) is a matrix composed of D Ha diagonal matrix composed of the diagonal elements of H c According to the cyclic property of H c H r may be expressed as:

[0108]

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

[0110] Based on the calculation of the cyclic matrix H c of the transceiver channel in S301, SVD decomposition can be performed to obtain the unitary matrix and The specific expression is as follows:

[0111]

[0112] wherein, is a diagonal matrix containing the singular values of H c .

[0113] The relationship between the joint phase matrix and the cyclic matrix of the transceiver channel is designed as: H c = W r HW t Therefore, the joint phase matrix W r and W t are:

[0114]

[0115] S303, based on the joint phase matrix of the transceiver, diagonal matrix W H H c y is used to eliminate the intermodular crosstalk of the sending 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, deliberate interference cancellation: based on the interference channel state information and the joint phase matrix of the transceiver, the orthogonality of the vortex electromagnetic wave mode is used to select the L modes with the least interference effect as the carrier of L signal multiplexing transmission for L signal multiplexing transmission; the sending end performs power allocation on the L multiplexing signals to realize maximum spectral efficiency under interference.

[0118] S401, based on W r and the interference channel state information, the sending end performs WH W r h j Calculate, decompose the interference to each mode, select the L modes affected by the interference as the carrier of L signal multiplexing transmission.

[0119] S402, the sending end carries out power allocation on the L multiplexing signals, and realizes maximum spectrum efficiency under interference.

[0120] The present application maximizes the capacity upper bound C OS , so as to find the optimal power allocation scheme, so that the spectrum efficiency of the system is maximized in the presence of interference, thereby improving the anti-interference performance of the system.

[0121] The capacity upper bound C OS Resist the interference, expressed as:

[0122]

[0123] Wherein, Indicates the number of activated mode combinations, 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, that is, the capacity upper bound C OS Max, the spectrum efficiency maximization problem can be expressed as P1, as follows:

[0125]

[0126] Wherein, P t Is the total transmission power, P th Is the minimum allocation power threshold.

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

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

[0129] S404, the receiving end utilizes DFT (Discrete Fourier transform, Discrete Fourier transform) matrix to demodulate, and the demodulated signal The specific expression is as follows:

[0130]

[0131] wherein, Λ H = W H H c W is a diagonal matrix after DFT processing.

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

[0133]

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

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

[0136]

[0137] In order to further illustrate the superiority of the present application, the following experiment can be used for further illustration:

[0138] In this embodiment, the carrier frequency is set to 2.4 GHz, the radius of the sending end UCA is λ, the radius of the receiving end UCA is 4λ, the radius of the first receiving UCA of the sending end is 4λ, the radius of the second receiving UCA of the sending end is 6λ, the coordinates of the interference source are (5, 20, 35) m, and the simulation conditions are that the sending-to-noise ratio is 20 dB. The interference source position estimation based on the EMUSIC joint RSS algorithm proposed in the present application is simulated, and the spectral efficiency of the anti-interference scheme in the case of perception assistance and non-perception assistance is analyzed, as well as the influence of different power allocation methods on the spectral efficiency of the anti-interference scheme. Figure 3 By comparing the estimated interference source position with the actual position, it is found that the estimated interference source position is very close to the actual position, which verifies the effectiveness of the EMUSIC joint RSS algorithm proposed in the present application. The conventional mode selection scheme has a certain probability to select the L worst modes for L multiplexing transmission of signals without using perception assistance. Therefore, the spectral efficiency is low and the average level is shown.Figure 3 The spectral efficiency of the anti-interference scheme with and without perception assistance is also compared. In the simulation, L=4 and N=16. It can be observed that the perception-assisted anti-interference scheme proposed in the application has higher spectral efficiency than that without perception assistance. This is because the perception capability allows the proposed scheme to dynamically select the mode with the highest signal-to-noise ratio and the least interference, thereby effectively mitigating the interference attack.

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

[0140] As can be seen, the perception-assisted anti-interference method proposed in the application can achieve accurate positioning of the interference source position with the help of the EMUSIC joint RSS algorithm, and improve the anti-interference performance of the wireless communication system under deliberate interference, meeting the requirements of modern communication.

[0141] An embodiment of the application provides a perception-assisted vortex electromagnetic anti-interference system, comprising:

[0142] An interference source position confirmation module is configured to estimate the position information of the interference source based on the received interference signal, and obtain the interference channel state information.

[0143] An inter-mode interference cancellation module is configured to design a transceiver joint phase matrix using the interference channel state information, wherein the transceiver joint phase matrix comprises a phase matrix of a receiving end and a phase matrix of a transmitting end.

[0144] A deliberate interference cancellation module is configured to select L modes with the least interference as carriers for multiplexing transmission of L signals using the orthogonality of vortex electromagnetic wave modes based on the interference channel state information and the transceiver joint phase matrix, and perform power allocation on the L multiplexed signals to maximize the spectral efficiency under interference.

[0145] A signal demodulation module is configured to send signals to a receiving end and demodulate the signals to recover the mode signals, thereby achieving interference suppression.

[0146] An embodiment of the application provides a perception-assisted vortex electromagnetic wave anti-interference device, comprising a memory and a processor. When the processor invokes the computer program or instructions in the memory, the above-mentioned perception-assisted vortex electromagnetic wave anti-interference method is executed.

[0147] One embodiment of the present application provides a computer readable storage medium, which stores a computer program, and when the program is executed by a processor, a perception-assisted vortex electromagnetic wave anti-interference method can be realized. The computer readable storage medium is a memory device in a terminal device, used for storing programs and data. It can be understood that the computer readable storage medium herein can include a built-in storage medium in the terminal device, and of course can include an expansion storage medium supported by the terminal device, and can be any tangible medium containing or storing a program, which can be used by or in combination with an instruction execution system, device or apparatus. The computer readable storage medium provides a storage space, which stores an operating system of the terminal. Moreover, one or more instructions suitable for being loaded and executed by the processor are also stored in the storage space, and the instructions can be one or more computer programs (including program codes). It should be noted that more specific examples (non-exhaustive list) of the computer readable storage medium include an electrical connection with one or more conductive wires, 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. The computer readable storage medium also includes a data signal propagating in a baseband or as a part of a carrier wave, which carries readable program codes. Such a propagating data signal can take various 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 the readable storage medium, which can send, propagate or transmit programs for use by or in combination with an instruction execution system, device or apparatus. The program codes contained in the readable storage medium can be transmitted by any suitable medium, including but not limited to wireless, wired, optical cable, RF, etc., or any suitable combination of the above.

[0148] The above merely provides preferred embodiments of the present application, and is not intended to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A perception-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; The interference channel state information is used to design a joint transmit-receive phase matrix, which includes a phase matrix of the receiving end and a phase matrix of the transmitting end. The joint transmit-receive phase matrix is ​​specifically designed as follows: Determine the circulant matrix of the transmit and receive channel based on the channel information from the transmitter to the receiver ; Specifically: perform singular value decomposition on the transmit and receive channel matrix to obtain the circulant matrix ; Circular matrix based on the transmit and receive channels Design the transmit-receive joint phase matrix; specifically: 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: in, is the phase matrix at the receiving end, is the phase matrix of the transmitter, and H is the The channel matrix from the transmitter to the receiver is composed of For sending UCA antenna n array element to the receiving UCA antenna m The channel vector of the array elements, 1≤ m ≤ M ; M is the number of array elements of the receiving UCA antenna; Based on the joint phase matrix of transmission and reception, the circulant matrix The diagonal matrix of Eliminate inter-mode crosstalk, where The first n Array elements and modes l Phase relationship IDFT matrix composed of 1≤ n ≤ N ; N is the number of elements of the transmitting UCA antenna; represents the DFT matrix; Based on the interference channel state information and the joint phase matrix of transmission and reception, the orthogonality of vortex electromagnetic wave modes is used to select the channel with the least interference effect. L modalities as carriers L Multiplexing transmission of channel signals and L Multiplex signals for power distribution to maximize spectrum efficiency under interference; Send the signal to the receiving end and decode the mode to restore the signal of each mode to achieve interference suppression.

2. The perception-assisted vortex electromagnetic wave anti-interference method according to claim 1, 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 antenna center; 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 antenna center; 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, characterized in that: Maximize spectrum efficiency under interference, specifically: Based on the interference channel state information, the modal interference distribution is obtained and the one least affected by the interference is selected. L modal as a carrier, L The power of each mode is found to maximize the spectrum efficiency.

4. The perception-assisted vortex electromagnetic wave anti-interference method according to claim 1, characterized in that: The specific implementation of interference suppression is as follows: The receiver uses the DFT matrix to demodulate the signal sent by the transmitter 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: in, , is the phase matrix at the receiving end, represents the DFT matrix; The transmission power of each mode is The combined diagonal matrix; It contains l Useful signals of the line vector, Represents the transpose of a matrix; Interference signal emitted by the interference source; for the reason The channel gain from the interference source to the receiving end; The mean value received by the receiver is 0 and the variance is Additive white Gaussian noise.

5. 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 4 is implemented.

6. 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 to 4.

7. A sensing-assisted vortex electromagnetic anti-interference system, based on the sensing-assisted vortex electromagnetic wave anti-interference method according to claim 1, 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 interference channel state information; An inter-mode interference cancellation 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 the channel least affected by interference based on the interference channel state information and the joint phase matrix of transmission and reception, and the orthogonality of the vortex electromagnetic wave mode. L modalities as carriers L Multiplexing transmission of channel signals and L Multiplex signals for power distribution to maximize spectrum efficiency under interference; The signal demodulation module is used to send signals to the receiving end and demodulate them, recovering each modal signal and achieving interference suppression.

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