Communication satellite interference source positioning method and system

Abstract

The invention provides a communication satellite interference source positioning method, which comprises the following steps of: modeling a phased array flow pattern, an interference signal and a signal received by an array element to obtain a corresponding signal model; resolving the signal model through a multiple signal classification algorithm to obtain the direction of arrival of the interference signal radiated to the phased array; performing angle conversion on the direction of arrival to obtain a pitch angle and an azimuth angle under a star body coordinate system; and converting the pitch angle and the azimuth angle under the satellite body coordinate system into longitude and latitude under a geocentric coordinate system through coordinate system conversion so as to determine the position of an interference source. The invention also provides a communication satellite interference source positioning system. Therefore, the problem of interference faced by user communication is effectively solved.

Description

Technical Field

[0001] The present invention relates to the technical field of communication satellites, and in particular to a method and system for locating interference sources of communication satellites. Background Art

[0002] With the growth of satellite data services, the demand for communication network coverage and capacity is also increasing, and the mission types are becoming more and more complex. Satellites inevitably receive interference signals other than user signals. The main interferences faced by satellite communications include ground interference, space interference, natural interference, and man-made interference. The presence of interference signals affects the quality of user communications.

[0003] In order to ensure the safety and smoothness of user communication channels, interference avoidance is a relatively simple and efficient method without using anti-interference technology. Common interference avoidance solutions include frequency domain isolation and spatial isolation. Frequency domain isolation refers to adjusting the gain of the frequency band where the interference signal is located to zero (while sacrificing the user signals in the frequency band, or re-adjusting the frequency plan), and spatial isolation refers to first locating the spatial position of the interference signal, and then using beamforming technology to readjust the beam pointing to the interference source outside the beam coverage area (3dB width).

[0004] Most existing interference avoidance methods are to adjust the gain of the frequency band to zero, that is, to use a built-in shutdown function to achieve interference avoidance, but the existing method will cause communication interruption for some users.

[0005] Angle of arrival (DOA) estimation is one of the commonly used technical means for radar target detection and positioning. DOA estimation is based on the signal received by the phased array, and uses the phenomenon that there is a phase difference between array elements in different directions of the wave to solve the direction of the signal. Traditional communication satellites generally use fixed large beams, which cannot avoid interference signal areas. With the popularization of phased array technology, communication satellites have the ability to flexibly shape beams, and are expected to have the ability to avoid interference signals. Phased arrays are used to locate communication interference sources, and the amplitude and phase coefficients of array elements are adjusted in orbit to reshape the beam coverage area. Summary of the invention

[0006] The purpose of the present invention is to provide a communication satellite interference source positioning method and system for solving the interference problem faced by user communications.

[0007] In order to achieve the above object, on the one hand, the present invention provides a method for locating a communication satellite interference source, comprising the steps of:

[0008] Model the phased array flow pattern, interference signal, and signal received by the array element to obtain the corresponding signal model;

[0009] Solving the signal model by a multiple signal classification algorithm to obtain the arrival angle of the interference signal radiated to the phased array;

[0010] Performing angle conversion on the angle of arrival to obtain the pitch angle and azimuth angle in the satellite body coordinate system;

[0011] The pitch angle and the azimuth angle in the satellite body coordinate system are transformed into longitude and latitude in the geocentric coordinate system through coordinate system transformation to determine the location of the interference source.

[0012] Furthermore, the modeling of the phased array flow pattern, the interference signal, and the signal received by the array element to obtain the corresponding signal model includes:

[0013] By modeling the signal received by the array element, the model of the signal received by each array element at the kth sampling point is obtained as follows:

[0014] X(k)=AS(k)+N(k);

[0015] N(k)=[n1(k),K,n M (k)] T ;

[0016] By modeling the phased array flow pattern, the steering vector array is obtained as follows:

[0017] A=[a(θ1),K,a(θ p )];

[0018]

[0019] By modeling the interference signal, the spatial signal vector is obtained as:

[0020] S(k)=[s1(k), k, s p (k)] T ;

[0021] Wherein, M represents the number of array elements, p represents the number of interference sources, and N represents the noise data vector.

[0022] Further, solving the signal model by a multiple signal classification algorithm to obtain the arrival angle of the interference signal radiated to the phased array includes:

[0023] Constructing an array covariance matrix corresponding to the signal model;

[0024] Performing eigendecomposition on the array covariance matrix;

[0025] According to the MUSIC space spectrum function, the angle of arrival is obtained by searching for the minimum value of the component of the steering vector in the signal subspace in the noise subspace.

[0026] Furthermore, the expression of the array covariance matrix is:

[0027] R XX =E[XX H ]

[0028] =AE[SS H ]A H +E[NN H ];

[0029] =AR SS A H +R NN

[0030] Among them, R SS is the signal covariance matrix, R NN is the noise covariance matrix;

[0031] The expression after eigendecomposition of the array covariance matrix is:

[0032]

[0033] Among them, U S =Σ S The corresponding eigenvector spans the signal subspace, U N =Σ N The noise subspace spanned by the corresponding eigenvectors, Σ S is composed of eigenvalues ​​λ1, λ2, L, λ p The diagonal matrix Σ N The eigenvalue λ p+1 ,λ p+2 , L, λ M The diagonal matrix is ​​composed of the eigenvalues ​​λ1, λ2, L, λ p is the signal power and is represented by p larger eigenvalues ​​in the array covariance matrix; the eigenvalue λ p+1 ,λ p+2 , L, λ M is the array processing error and noise power, and is represented by Mp smaller eigenvalues ​​in the array covariance matrix;

[0034] The expression of the MUSIC spatial spectrum function is:

[0035]

[0036] Where a(θ) is the signal subspace U S The steering vector of

[0037] The minimum value of the component of the steering vector in the noise subspace is calculated based on the following formula:

[0038] θ MUSIC = argmin{a H (θ)U N U N H a(θ)}.

[0039] Furthermore, the wave arrival angle includes a first incident angle corresponding to the x-axis and a second incident angle corresponding to the y-axis in the local satellite coordinate system;

[0040] Performing angle conversion on the angle of arrival to obtain the pitch angle and azimuth angle in the satellite body coordinate system includes:

[0041] Through the formula cos 2 α+cos 2 φ x +cos 2 φ y =1, calculate the pitch angle of the said angle of arrival in the satellite body coordinate system;

[0042] By formula Calculating the azimuth of the angle of arrival in the satellite body coordinate system;

[0043] Wherein, α is the pitch angle; β is the azimuth angle; φ x is the angle between the interference source and the x-axis of the local satellite coordinate system, φ x =90°-θ x ; φ y is the angle between the interference source and the y-axis of the satellite coordinate system, φ y =90°-θ y θ x is the first incident angle, θ y is the second incident angle.

[0044] Further, the step of transforming the pitch angle and the azimuth angle in the satellite body coordinate system into longitude and latitude in the geocentric coordinate system through a coordinate system transformation to determine the location of the interference source includes:

[0045] Calculating the distance of the interference source according to the pitch angle and the satellite orbit position in the satellite body coordinate system;

[0046] Calculate the position coordinates of the interference source in the satellite body coordinate system according to the pitch angle, the azimuth angle and the distance;

[0047] The position coordinates of the interference source in the satellite body coordinate system are transformed into the longitude and latitude in the geocentric coordinate system to obtain the actual position of the interference source.

[0048] Furthermore, the distance of the interference source is calculated based on the following formula:

[0049]

[0050] Where R is the radius of the earth, R H is the orbit height;

[0051] The position coordinates of the interference source in the satellite body coordinate system are calculated based on the following formula:

[0052] x0=lu;

[0053] y0=-lv;

[0054] u = sin(α)cos(β);

[0055] v = sin(α)sin(β);

[0056] Wherein, (x0, y0) is the position coordinate of the interference source in the satellite body coordinate system.

[0057] Furthermore, the actual position of the interference source is calculated based on the following formula:

[0058] lon0=Δlon+lon s ;

[0059] lat0=Δlat+lat s ;

[0060] Δlon=sin -1 (x0 / R / cos(Δlat));

[0061] Δlat=sin -1 (-y0 / R);

[0062] Wherein, Δlon represents the longitude difference between the satellite and the interference source; Δlat represents the latitude difference between the satellite and the interference source; lon s Indicates the longitude of the satellite; lat s Indicates the latitude of the satellite.

[0063] On the other hand, based on the same inventive concept, the present invention also provides a communication satellite interference source positioning system, which is used to implement any of the above-mentioned communication satellite interference source positioning methods.

[0064] The communication satellite interference source positioning method described in the present invention obtains the corresponding signal model by modeling the phased array array flow pattern, interference signal and signal received by the array element; solves the signal model through a multiple signal classification algorithm to obtain the wave angle of the interference signal radiated to the phased array; performs angle conversion on the wave angle to obtain the pitch angle and azimuth in the star body coordinate system; transforms the pitch angle and azimuth in the star body coordinate system to the longitude and latitude in the geocentric coordinate system through the coordinate system transformation to determine the interference source position. That is, the present invention uses the phase difference of the interference signal received by different array elements of the phased array to solve the incident angle when the interference signal reaches the phased array, and converts it into the pitch angle and azimuth in the star body coordinate system through angle transformation, and then obtains the longitude and latitude coordinates of the interference source through a series of coordinate transformations; in this way, when interference avoidance is required, the beam coverage area can be reshaped according to the position of the interference source. BRIEF DESCRIPTION OF THE DRAWINGS

[0065] Figure 1 A flowchart showing the steps of the communication satellite interference source positioning method provided by one embodiment of the present invention;

[0066] Figure 2 A schematic diagram of a satellite body coordinate system of a communication satellite is shown;

[0067] Figure 3 A schematic diagram of a phased array L-type array system of the communication satellite interference source positioning method provided by an embodiment of the present invention is shown;

[0068] Figure 4 A schematic diagram showing the spatial spectrum estimation results of a specific example of the communication satellite interference source positioning method of the present invention. DETAILED DESCRIPTION

[0069] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0070] It should be noted that references to "one embodiment", "embodiment", "example embodiment", etc. in this specification refer to the embodiment described, which may include specific features, structures or characteristics, but not every embodiment must include these specific features, structures or characteristics. In addition, such expressions do not refer to the same embodiment. Furthermore, when describing specific features, structures or characteristics in conjunction with an embodiment, whether or not there is an explicit description, it has been shown that it is within the knowledge of those skilled in the art to combine such features, structures or characteristics into other embodiments.

[0071] In addition, certain words are used in the specification and subsequent claims to refer to specific components or parts. Those with ordinary knowledge in the relevant field should understand that manufacturers can use different nouns or terms to refer to the same component or part. This specification and subsequent claims do not use differences in names as a way to distinguish components or parts, but use differences in the functions of components or parts as the criteria for distinction. "Including" and "including" mentioned throughout the specification and subsequent claims are open-ended terms and should be interpreted as "including but not limited to". In addition, the word "connected" here includes any direct and indirect electrical connection means. Indirect electrical connection means include connection through other devices.

[0072] The present invention provides a communication satellite interference source positioning method, which is used for positioning the signal source that causes signal interference to the communication satellite, and is specifically applicable to the positioning of interference sources such as high-throughput satellites, relay satellites and other satellites. Specifically, the incident angle of the communication interference source signal radiated to the phased array is calculated through phased array array flow type modeling, interference signal modeling, array receiving signal modeling, and multiple signal classification algorithms, and then the incident angle is converted into an angle with the coordinate axis in the satellite body coordinate system, and further converted into a pitch angle and an azimuth angle; finally, the pitch angle and azimuth angle information are converted into the longitude and latitude coordinates of the communication interference source on the earth according to orbital parameters; thereby, the interference problem faced by user communications can be solved.

[0073] Figure 1 A communication satellite interference source positioning method provided by an embodiment of the present invention includes the following steps:

[0074] S101: Model the phased array flow pattern, interference signal, and signal received by the array element to obtain a corresponding signal model. The phased array flow pattern is a mathematical model used to describe the phase (and amplitude) relationship of the signal on each array element of the phased array antenna; the interference signal refers to the noise signal that interferes with the phased array antenna on the satellite; the signal received by the array element is the signal received by each array element on the phased array antenna.

[0075] In specific implementation, step S101 includes: by modeling the signal received by the array element, the model of the signal received by each array element at the kth sampling point is obtained as follows:

[0076] X(k)=AS(k)+N(k);

[0077] N(k)=[n1(k),K,n M (k)] T ;

[0078] By modeling the phased array flow pattern, the steering vector array is obtained as follows:

[0079] A=[a(θ1),K,a(θ p )];

[0080]

[0081] By modeling the interference signal, the spatial signal vector is obtained as:

[0082] S(k)=[s1(k),K,s p (k)] T ;

[0083] Among them, M represents the number of array elements, p represents the number of interference sources, and N represents the noise data vector; that is, the matrix A is the array flow type of the phased array, and the spatial signal vector S is the interference signal.

[0084] S102: Solving the signal model by a multiple signal classification algorithm to obtain the arrival angle of the interference signal radiated to the phased array.

[0085] In specific implementation, step S102 includes: constructing an array covariance matrix corresponding to the signal model; performing eigendecomposition on the array covariance matrix; and obtaining the angle of arrival by searching for the minimum value of the component of the steering vector of the signal subspace on the noise subspace according to the MUSIC space spectrum function.

[0086] The expression of the constructed array covariance matrix is:

[0087] R XX =E[XX H ]

[0088] =AE[SS H ]A H +E[NN H ];

[0089] =AR SS A H +R NN

[0090] Among them, R SS is the signal covariance matrix, R NN is the noise covariance matrix; in the case of ideal Gaussian white noise, let the noise power be σ 2 , then R NN =σ 2 I; then R XX It can also be expressed as:

[0091] R XX =AR SS A H +σ 2 I.

[0092] Furthermore, the array covariance matrix R XX Perform eigendecomposition:

[0093] R XX =UΣU H ;

[0094] Where U is the eigenvector matrix and Σ is the diagonal matrix of eigenvalues. If the signals received by the array are uncorrelated, then the M×M-dimensional array covariance matrix R XX is full rank, let λ1,λ2,…,λ M are the M eigenvalues ​​of the diagonal matrix Σ, and each eigenvalue satisfies the relationship:

[0095] λ1≥λ2≥…≥λ p ≥λ p+1 =…=λ M =σ 2 ;

[0096] Then the diagonal matrix Σ is expressed as:

[0097]

[0098] This embodiment defines the large eigenvalues ​​λ1,λ2,…,λ p The diagonal matrix Σ S :

[0099]

[0100] And by the small eigenvalue λ p+1 ,λ p+2 ,…,λ M The diagonal matrix Σ N

[0101]

[0102] Let U S =Σ S The corresponding eigenvector spans the signal subspace, U N =Σ N The noise subspace spanned by the corresponding eigenvectors is decomposed into the eigenvector matrix U and the signal subspace U S and the noise subspace U N Represents, then the array covariance matrix R XX Can be decomposed into:

[0103]

[0104] That is, the expression after eigendecomposition of the array covariance matrix is:

[0105]

[0106] Among them, U S =Σ S The corresponding eigenvector spans the signal subspace, U N =Σ N The noise subspace spanned by the corresponding eigenvectors, Σ S is composed of eigenvalues ​​λ1, λ2, L, λ p The diagonal matrix Σ N The eigenvalue λ p+1 ,λ p+2 , L, λ M The diagonal matrix is ​​composed of the eigenvalues ​​λ1, λ2, L, λ p is the signal power and is represented by p larger eigenvalues ​​in the array covariance matrix; the eigenvalue λ p+1 ,λ p+2 , L, λ M is the array processing error and noise power, and appears as Mp smaller eigenvalues ​​in the array covariance matrix.

[0107] Next, the angle of arrival is calculated based on the above calculation results. Under theoretical analysis conditions, the signal and noise are orthogonal, so the signal subspace U S With the noise subspace U N are also mutually orthogonal, so U S The steering vector a(θ) and U N Mutually orthogonal:

[0108] a H (θ)U N =0;

[0109] The DOA is solved by the multiple signal classification algorithm by searching for the steering vector a(θ) in U N This is achieved by taking the minimum value of the upper component:

[0110] θ MUSIC = argmin{a H (θ)U N U N H a(θ)};

[0111] The expression of the MUSIC spatial spectrum function is:

[0112]

[0113] Where a(θ) is the signal subspace U S The steering vector of

[0114] That is, the minimum value of the component of the steering vector in the noise subspace is calculated based on the following formula:

[0115] θ MUSIC = argmin{a H (θ)U N U N H a(θ)}.

[0116] S103: Perform angle conversion on the said wave arrival angle to obtain the pitch angle and azimuth angle in the satellite body coordinate system. The satellite body coordinate system takes the satellite as the coordinate origin, defines the z axis as the direction of the satellite pointing to the center of the earth, the x axis as the direction of the satellite running, and the y axis as the direction perpendicular to the orbital plane to the south; in this way, it is assumed that the x and y axis definitions in the phased array plane are consistent with the x and y axis definitions in the satellite body coordinate system. If the first incident angle θ corresponding to the x and y axes is calculated in step S102 x and the second incident angle θ y ;but:

[0117] Through the formula cos 2 α+cos 2 φ x +cos 2 φ y =1, calculate the pitch angle of the said angle of arrival in the satellite body coordinate system;

[0118] By formula Calculating the azimuth of the angle of arrival in the satellite body coordinate system;

[0119] Among them, α is the pitch angle, which reflects the angle of the interference source deviating from the +z axis; β is the azimuth angle, which reflects the angle of the interference source deviating from the +x axis after being mapped to the xoy plane; φ x is the angle between the interference source and the x-axis of the local satellite coordinate system, φ x =90°-θ x ; φ y is the angle between the interference source and the y-axis of the satellite coordinate system, φ y =90°-θ y θ x is the first incident angle, θ y is the second incident angle.

[0120] S104: The elevation angle and the azimuth angle in the satellite body coordinate system are transformed into the longitude and latitude in the geocentric coordinate system through a coordinate system transformation to determine the location of the interference source.

[0121] In specific implementation, step S104 includes: calculating the distance of the interference source based on the pitch angle and satellite orbit position in the star body coordinate system; calculating the position coordinates of the interference source in the star body coordinate system based on the pitch angle, azimuth and the distance; transforming the position coordinates of the interference source in the star body coordinate system to the longitude and latitude in the geocentric coordinate system to obtain the actual position of the interference source.

[0122] Furthermore, the distance of the interference source is calculated based on the following formula:

[0123]

[0124] Where R is the radius of the earth, R H is the orbit height;

[0125] The position coordinates of the interference source in the satellite body coordinate system are calculated based on the following formula:

[0126] x0=lu;

[0127] y0=-lv;

[0128] u = sin(α)cos(β);

[0129] v = sin(α)sin(β);

[0130] Among them, (x0, y0) is the position coordinate of the interference source in the satellite body coordinate system. That is, define the UV coordinate system, which uses distance as a measurement indicator and takes the satellite as the center. The coordinate points in the UV coordinate system reflect the position of any point on the surface of the earth that deviates from the satellite's earth-centered axis in the satellite's perspective. u is the distance between the projection of a point along the beam direction and the coordinate origin of 1 on the xoz plane and the z axis, and v is the distance between a point along the beam direction and the coordinate origin of 1 and the xoz plane; the +V axis is the direction of the sub-satellite point pointing to the due north, and the +U axis is the direction of the sub-satellite point pointing to the due east.

[0131] Furthermore, the actual location of the interference source is calculated based on the following formula:

[0132] lon0=Δlon+lon s ;

[0133] lat0=Δlat+lat s ;

[0134] Δlon=sin -1 (x0 / R / cos(Δlat));

[0135] Δlat=sin -1 (-y0 / R);

[0136] Wherein, Δlon represents the longitude difference between the satellite and the interference source; Δlat represents the latitude difference between the satellite and the interference source; lon s Indicates the longitude of the satellite; lat s Indicates the latitude of the satellite.

[0137] In a specific implementation of this embodiment, the phased array is modeled using an L-type array (including an x-axis and a y-axis) as an example, and the interference signal is modeled using a narrowband signal (the frequency is much larger than the bandwidth) as an example. The sampling signal of each array element on the x (y) axis at the kth snapshot, that is, the received signal at the kth sampling point is: X(k)=AS(k)+N(k).

[0138] The satellite coordinate system established according to the satellite orbit position and the earth position is as follows Figure 2 As shown in the figure, the satellite z-axis points to the earth and the x-axis points to the direction of the satellite's movement. Assuming that the phased array plane is located on the xoy plane, taking the phased array L-type array as an example, its distribution diagram is as follows Figure 3 shown.

[0139] Assume that an interference source is located at (115°E, 10°N) and a high-throughput satellite is located at the GEO orbit position (R H =35786km, R = 6371km) at (110°E, 0°N), the number of array elements on the x and y axes of the L-shaped array is 12, and the average signal-to-noise ratio of the received interference signal is 4dB. At the same time, other system simulation parameters such as frequency band and array element spacing that basically do not affect the positioning results but are necessary in the positioning solution process are given.

[0140] According to step S101 and the system parameters, the interference signals received by the x-axis and y-axis of the L-shaped array can be obtained and substituted into the MUSIC algorithm of step S102 as input. It should be noted that in practical applications, since the data received by the array is limited, the maximum likelihood estimation of the array covariance is adopted. Perform analysis and processing:

[0141]

[0142] Where L is the signal length. By searching the spectrum peak using the MUSIC algorithm, we can obtain the incident angles of the interference source signal radiated to the x-axis and y-axis, which are 0.88° and -1.705° respectively. The results are as follows: Figure 4 shown.

[0143] Substituting the two incident angles into step S103 for angle conversion, the pitch angle α is 1.9188° and the azimuth angle β is 62.6979°.

[0144] Then, step S103 is converted into an angle to obtain a pitch angle α of 1.9188° and an azimuth angle β of 62.6979°. Substituting them into step S104, the position of the interference source is obtained as (115.0392°E, 9.6573°N). The error between the analysis and calculation result and the actual position (115°E, 10°N) is:

[0145] Error=Rcos -1 (sin9.6573°×sin10°+cos9.6573°×cos10°×cos(115.0392-115)°);

[0146] =38.3482km

[0147] The positioning error is mainly affected by the number of array elements and the signal-to-noise ratio. Table 1 below shows the positioning results of the present invention under different numbers of array elements and different signal-to-noise ratios.

[0148] Table 1:

[0149]

[0150]

[0151] It can be seen from Table 1 that the more array elements involved in positioning solution, the smaller the positioning error; the higher the signal-to-noise ratio of the interference source signal, the more accurate the positioning.

[0152] In another embodiment, the present invention further provides a communication satellite interference source positioning system, which is used to implement the communication satellite interference source positioning method provided in the above embodiment.

[0153] Specifically, the communication satellite interference source positioning system may include an angle of arrival estimation module, an angle conversion module and a coordinate system transformation module, wherein:

[0154] The angle of arrival estimation module is used to solve the incident angle of the communication interference source signal radiated to the phased array, including the modeling of the phased array array flow type, the modeling of the interference signal, the modeling of the array element receiving signal, the multiple signal classification algorithm solution and other functions; the angle conversion module is used to convert the incident angle into the angle with the coordinate axis in the satellite body coordinate system, and further convert it into the pitch angle and azimuth angle; the coordinate system transformation module is used to convert the pitch angle and azimuth angle information into the longitude and latitude coordinates of the communication interference source on the earth according to the orbital parameters.

[0155] The specific functions of each module can refer to the specific steps of the communication satellite interference source positioning method in the above embodiment, which will not be repeated here.

[0156] In summary, the communication satellite interference source positioning method described in the present invention can use the phase difference of the interference signal received by different array elements of the phased array to calculate the incident angle of the interference signal when it reaches the phased array, and convert it into the pitch angle and azimuth angle in the satellite body coordinate system through angle transformation, and then obtain the longitude and latitude coordinates of the interference source through a series of coordinate transformations; in this way, when interference avoidance is needed, the beam coverage area can be reshaped according to the position of the interference source.

[0157] Of course, the present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art may make various corresponding changes and modifications based on the present invention, but these corresponding changes and modifications should all fall within the scope of protection of the claims attached to the present invention.

Claims

1. A method for locating a communication satellite interference source, characterized in that: Includes steps: Model the phased array flow pattern, interference signal, and signal received by the array element to obtain the corresponding signal model; Solving the signal model by a multiple signal classification algorithm to obtain the arrival angle of the interference signal radiated to the phased array; Performing angle conversion on the angle of arrival to obtain the pitch angle and azimuth angle in the satellite body coordinate system; The pitch angle and the azimuth angle in the satellite body coordinate system are transformed into longitude and latitude in the geocentric coordinate system through coordinate system transformation to determine the location of the interference source.

2. The communication satellite interference source positioning method according to claim 1, characterized in that: The modeling of the phased array flow pattern, the interference signal, and the signal received by the array element to obtain the corresponding signal model includes: By modeling the signal received by the array element, the model of the signal received by each array element at the kth sampling point is obtained as follows: X(k)=AS(k)+N(k); N(k)=[n1(k),K,n M (k)] T ; By modeling the phased array flow pattern, the steering vector array is obtained as follows: A=[a(θ1),K,a(θ p )]; By modeling the interference signal, the spatial signal vector is obtained as: S(k)=[s1(k),K,s p (k)] T ; Wherein, M represents the number of array elements, p represents the number of interference sources, and N represents the noise data vector.

3. The communication satellite interference source positioning method according to claim 2, characterized in that: The solving the signal model by a multiple signal classification algorithm to obtain the arrival angle of the interference signal radiated to the phased array includes: Constructing an array covariance matrix corresponding to the signal model; Performing eigendecomposition on the array covariance matrix; According to the MUSIC space spectrum function, the angle of arrival is obtained by searching for the minimum value of the component of the steering vector in the signal subspace in the noise subspace.

4. The communication satellite interference source positioning method according to claim 3, characterized in that: The expression of the array covariance matrix is: Among them, R SS is the signal covariance matrix, R NN is the noise covariance matrix; The expression after eigendecomposition of the array covariance matrix is: Among them, U S =Σ S The corresponding eigenvector spans the signal subspace, U N =Σ N The noise subspace spanned by the corresponding eigenvectors, Σ S is composed of eigenvalues ​​λ1, λ2, L, λ p The diagonal matrix Σ N The eigenvalue λ p+1 ,λ p+2 , L, λ M The diagonal matrix is ​​composed of the eigenvalues ​​λ1, λ2, L, λ p is the signal power and is represented by p larger eigenvalues ​​in the array covariance matrix; the eigenvalue λ p+1 ,λ p+2 , L, λ M is the array processing error and noise power, and is represented by Mp smaller eigenvalues ​​in the array covariance matrix; The expression of the MUSIC spatial spectrum function is: Among them, a(θ) is the signal subspace U S The steering vector of The minimum value of the component of the steering vector in the noise subspace is calculated based on the following formula: i MUSIC =argmin{a H (i)U N U N H a(θ)}.

5. The communication satellite interference source positioning method according to claim 1, characterized in that: The said angle of arrival includes a first incident angle corresponding to the x-axis and a second incident angle corresponding to the y-axis in the local satellite coordinate system; Performing angle conversion on the angle of arrival to obtain the pitch angle and azimuth angle in the satellite body coordinate system includes: Through the formula cos 2 α+cos 2 φ x +cos 2 φ y =1, calculate the pitch angle of the said angle of arrival in the satellite body coordinate system; By formula Calculating the azimuth of the angle of arrival in the satellite body coordinate system; Wherein, α is the pitch angle; β is the azimuth angle; φ x is the angle between the interference source and the x-axis of the local satellite coordinate system, φ x =90°-θ x ; φ y is the angle between the interference source and the y-axis of the satellite coordinate system, φ y =90°-θ y θ x is the first incident angle, θ y is the second incident angle.

6. The communication satellite interference source positioning method according to claim 5, characterized in that: The step of transforming the pitch angle and the azimuth angle in the satellite body coordinate system into the longitude and latitude in the geocentric coordinate system through a coordinate system transformation to determine the location of the interference source comprises: Calculating the distance of the interference source according to the pitch angle and the satellite orbit position in the satellite body coordinate system; Calculate the position coordinates of the interference source in the satellite body coordinate system according to the pitch angle, the azimuth angle and the distance; The position coordinates of the interference source in the satellite body coordinate system are transformed into the longitude and latitude in the geocentric coordinate system to obtain the actual position of the interference source.

7. The communication satellite interference source positioning method according to claim 6, characterized in that: The distance of the interference source is calculated based on the following formula: Where R is the radius of the earth, R H is the orbit height; The position coordinates of the interference source in the satellite body coordinate system are calculated based on the following formula: x0=lu; y0=-lv; u = sin(α)cos(β); v = sin(α)sin(β); Wherein, (x0, y0) is the position coordinate of the interference source in the satellite body coordinate system.

8. The communication satellite interference source positioning method according to claim 7, characterized in that: The actual position of the interference source is calculated based on the following formula: lon0=Δlon+lon s ; lat0=Δlat+lat s ; Δlon=sin -1 (x0 / R / cos(Δlat)); <h2 style=";text-align:left;direction:ltr">Δlat=sin<h2 style=";text-align:left;direction:ltr"> -1 <h2 style=";text-align:left;direction:ltr"> (-y0 / R); Wherein, Δlon represents the longitude difference between the satellite and the interference source; Δlat represents the latitude difference between the satellite and the interference source; lon s Indicates the longitude of the satellite; lat s Indicates the latitude of the satellite.

9. A communication satellite interference source positioning system, characterized in that: The system is used to implement the communication satellite interference source positioning method as described in any one of claims 1 to 8.

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