A method for calculating the far-field spatial weighting phase of a phased array antenna element

Abstract

The application discloses a kind of far-field space weighting phase calculation methods of phased array antenna array element, it includes: for the signal synthesis of phased array antenna, signal transmitted from far-field virtual target and signal transmitted from far-field actual target are all regarded as the signal parallel with the array plane normal of phased array antenna;That is, with central element as reference point, for actual target and virtual target satisfying far-field condition, by calculating the wave path difference of signal transmitted from far-field actual target and / or far-field virtual target to the central element of phased array antenna and any element outside the central element, the equivalent space weighting phase of the arbitrary element is obtained.The application is simple, reliable and easy to implement, and can meet the demand of beam synthesis of phased array antenna system in engineering practice.

Description

Technical Field

[0001] This invention relates to the field of phased array antenna technology, and in particular to a method for calculating the far-field spatial weighted phase of a phased array antenna element. Background Technology

[0002] Digital multi-beam spherical phased array antennas have gained increasing attention in recent years as a hot research area in the field of new antennas due to their multi-beam operation and full-space coverage capabilities, enabling simultaneous tracking and control of multiple space targets.

[0003] A key technical challenge in the design of digital multi-beam spherical phased array antennas is achieving digital beamforming. A prerequisite for digital beamforming in a digital multi-beam phased array antenna is ensuring phase consistency across all antenna channels. Therefore, it is necessary to calculate the spatially weighted phase of each antenna element and then sum the phase compensation signals of the corresponding element channels to form a beamformed signal. For planar phased array antennas, a common engineering solution is to utilize the equivalent parallel waves of far-field targets and calculate the spatially weighted phase by calculating the spatial path difference between antenna elements. However, for spherical phased array antennas, the calculation formula for the spatial path difference of antenna elements is more complex and cumbersome in practical applications due to the need to consider the curvature of the antenna array surface. Summary of the Invention

[0004] In view of this, in order to meet the requirement of calculating the spatial weighted phase of each element antenna in a spherical phased array antenna system when performing beamforming on far-field spatial targets, this invention proposes a method for calculating the spatial weighted phase of a spherical phased array antenna in the far field. The aim is to provide a simple, reliable and easy-to-implement method for calculating the spatial weighted phase of the spherical phased array antenna elements. This method does not require any external equipment, making it easy to design a spherical phased array antenna system that meets the performance requirements in engineering practice.

[0005] This invention discloses a method for calculating the far-field spatially weighted phase of a phased array antenna element, comprising:

[0006] For signal synthesis of phased array antennas, both signals transmitted from far-field virtual targets and signals transmitted from far-field actual targets are considered to be signals parallel to the normal of the phased array antenna. That is, with the central array element as the reference point, for actual and virtual targets that meet the far-field conditions, the equivalent spatial weighted phase of the arbitrary array element is obtained by calculating the path difference between the signals transmitted by the far-field actual targets and / or far-field virtual targets reaching the central array element and any array element outside the central array element of the phased array antenna.

[0007] Furthermore, when the phased array antenna is a planar phased array, if the difference between the first distance difference and the second distance difference is less than a specified multiple of the wavelength of the signal transmitted by the far-field virtual target or the far-field virtual target, then the signal transmitted from the far-field virtual target and the signal transmitted from the far-field actual target are considered as signals parallel to the normal of the planar phased array antenna. The first distance difference is the distance difference between the signal transmitted by the far-field virtual target reaching the central array element and the first array element, and the second distance difference is the distance difference between the signal transmitted by the far-field actual target reaching the central array element and the first array element. The first array element is the array element with the longest distance from the center point of the array surface in the planar phased array antenna. The center point of the array surface is the center point of the central array element.

[0008] Furthermore, assuming the target lies on the normal line passing through the center point O of the planar phased array antenna, a coordinate system is established with the center point O of the planar phased array antenna as the center point, the line connecting the first array element to the center point O as the x-axis, and the normal line passing through the center point O of the planar phased array antenna as the y-axis. In this coordinate system, let the coordinates of the spatial target A be (0, y...). A The coordinates of the center point O of the planar phased array are (0,0), and the coordinates of the first element are (x1,0). Assume that spatial target A satisfies the far-field condition for the planar phased array antenna. Arbitrarily imagine a virtual target B on the y-axis that satisfies the far-field condition, and set its coordinates as (0,y). B The first element is the element in the phased array antenna that is furthest from the center point of the array surface.

[0009] If the distance y between the spatial target A and the center point O of the array is... A The distance between spatial target A and the first array element is L. 1A The distance difference ΔL between them 1A If the following formula is satisfied, then space target A is considered to satisfy the far-field condition:

[0010]

[0011] If the distance y between the virtual target B and the center point O of the array is... B The distance between the virtual target B and the first array element is L. 1B The distance difference ΔL between them 1B Virtual target B is considered to satisfy the far-field condition if it meets the following formula:

[0012]

[0013] Furthermore, when the phased array antenna is a spherical phased array, a virtual target that satisfies the far-field conditions is selected from the far field, and the coordinates of the virtual target in the spherical phased array coordinate system are calculated. Based on the distance from the central element of the spherical phased array to the virtual target, and the distance from the coordinates of any element on the spherical phased array to the virtual target, the path difference between the central element and any element is obtained. Based on the path difference, the equivalent spatial weighted phase of any element is obtained.

[0014] Furthermore, when the phased array antenna is a spherical phased array, when the distance from the space target to the center of the spherical phased array is greater than... When the target in space satisfies the far-field condition, r is the array radius of the spherical phased array, and f A is the maximum frequency point for the phased array to receive signals, and c is the speed of light; the first element is an element in a spherical phased array antenna whose distance from the center point of the array is the radius of the array.

[0015] Further, the calculation of the coordinates of the virtual target in the spherical phased array coordinate system includes:

[0016] In a spherical phased array antenna, establish a three-dimensional coordinate system with the center of the sphere as the origin. Let the azimuth angle of a space target satisfying the far-field condition in the coordinate system of the spherical array be . pitch angle is Furthermore, the array element on the array surface corresponding to the azimuth and elevation angles is defined as the central array element C, and its coordinates in the coordinate system of the spherical array are set as (x... C ,y C ,z C The coordinates (x, y) of the virtual target B in the spherical coordinate system are obtained according to the following formula. B ,y B ,z B ):

[0017]

[0018] Furthermore, the distance from the central element of the spherical phased array to the virtual target is calculated according to the following formula:

[0019] The distance L from the central array element C to the virtual target B CB :

[0020]

[0021] Furthermore, the distance from the coordinates of any element on the spherical phased array to the virtual target is calculated using the following formula:

[0022] The distance L from any element with coordinates (x1, y1, z1) on the spherical phased array to the virtual target B. 1B :

[0023]

[0024] Furthermore, the path difference from the central array element to any array element is obtained using the following method:

[0025] Let an arbitrary array element with coordinates (x1, y1, z1) be located at point D on the array surface. Draw a plane α tangent to the spherical surface of the spherical phased array antenna, passing through point C where the central array element is located. Let E be the intersection of plane α and line segment DB. The length of line segment BE is approximately equal to the length of line segment BC. Line segment DE represents the path difference ΔL between the array element with coordinates (x1, y1, z1) and the central array element C. 1C =L 1B -L CB .

[0026] Furthermore, obtaining the equivalent spatial weighted phase of any array element based on the path difference includes:

[0027] The equivalent spatial weighted phase Δφ of any array element with coordinates (x1, y1, z1) is calculated using the following formula. 1C :

[0028]

[0029] Where c is the speed of light, f A The maximum operating frequency of the phased array antenna is (). Taking the decimal part is for decimal operations.

[0030] Because of the adoption of the above technical solution, the present invention has the following advantages:

[0031] 1. This invention solves the problem of calculating the spatially weighted phase of phased array antenna elements relative to far-field targets. Based on the characteristics of far-field conditions of space targets, this invention proposes a method using virtual far-field space targets to calculate the spatially weighted phase of each element of the phased array antenna relative to the space target. This method is simple, reliable, and easy to implement, and can meet the beamforming requirements of phased array antenna systems in engineering practice. Using this method, phased array antenna systems that meet performance requirements can be designed in engineering practice, solving a key problem in the design of digital multi-beam phased array antenna systems.

[0032] 2. Simple to implement, low resource consumption, and reduced system design costs. This invention does not require complex circuits, making the implementation method relatively simple. It utilizes only existing system equipment without adding any extra devices, and implements the multi-level comparison method for channel phase consistency detection through software algorithms, facilitating automated operation and reducing system design costs. Attached Figure Description

[0033] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments recorded in the embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0034] Figure 1 This is a schematic diagram of the far-field target determination conditions for a phased array antenna.

[0035] Figure 2 This is a schematic diagram illustrating the calculation of the path difference between a traditional phased array antenna and a far-field target.

[0036] Figure 3 This is a schematic diagram of a phased array antenna using a virtual target method for targets that meet far-field conditions.

[0037] Figure 4 This is a schematic diagram of a spherical phased array antenna receiving signals from a far-field target.

[0038] Figure 5 This is a schematic diagram of the equivalent spatial weighted phase calculation of a virtual target for a far-field target using a spherical phased array antenna. Detailed Implementation

[0039] The present invention will be further described in conjunction with the accompanying drawings and embodiments. The described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art should fall within the protection scope of the present invention.

[0040] Traditionally, digital multi-beam phased array antenna systems typically calculate the spatial path difference of antenna elements using the equivalent parallel wave method, and then calculate the spatial weighted phase of each element for a far-field target. This method of calculating the spatial path difference requires calculating the arrival angle of each element separately, and for curved phased array antennas, the influence of the antenna surface curvature on the arrival angle of the elements must also be considered, making the calculation very cumbersome. This application proposes a method based on the characteristics of the far-field conditions of a space target, using a virtual far-field space target to calculate the spatial weighted phase of each element of a spherical phased array antenna for the target. This method is simple, reliable, and easy to implement, and can meet the beamforming requirements of spherical phased array antenna systems in engineering practice. Using this method, spherical phased array antenna systems that meet performance requirements can be designed in engineering practice.

[0041] This invention provides an embodiment of a method for calculating the far-field spatial weighted phase of a phased array antenna element, comprising:

[0042] For signal synthesis of phased array antennas, both signals transmitted from far-field virtual targets and signals transmitted from far-field actual targets are considered to be signals parallel to the normal of the phased array antenna. That is, with the central array element as the reference point, for actual and virtual targets that meet the far-field conditions, the equivalent spatial weighted phase of the arbitrary array element is obtained by calculating the path difference between the signals transmitted by the far-field actual targets and / or far-field virtual targets reaching the central array element and any array element outside the central array element of the phased array antenna.

[0043] In one embodiment of this application, when the phased array antenna is a planar phased array, if the difference between the first distance difference and the second distance difference is less than a specified multiple of the wavelength of the signal transmitted by the far-field virtual target or the far-field virtual target, then the signal transmitted from the far-field virtual target and the signal transmitted from the far-field actual target are regarded as signals parallel to the normal of the planar phased array antenna; the first distance difference is the distance difference between the signal transmitted by the far-field virtual target reaching the central array element and the first array element, and the second distance difference is the distance difference between the signal transmitted by the far-field actual target reaching the central array element and the first array element; the first array element is the array element with the longest distance from the center point of the array surface in the planar phased array antenna; the center point of the array surface is the center point of the central array element.

[0044] In one embodiment of this application, it is assumed that the target lies on the normal line passing through the center point O of the planar phased array antenna. A coordinate system is established with the center point O of the planar phased array antenna as the center point, the line connecting the first array element to the center point O as the x-axis, and the normal line passing through the center point O of the planar phased array antenna as the y-axis. In this coordinate system, let the coordinates of the spatial target A be (0, y). A The coordinates of the center point O of the planar phased array are (0,0), and the coordinates of the first element are (x1,0). Assume that spatial target A satisfies the far-field condition for the planar phased array antenna. Arbitrarily imagine a virtual target B on the y-axis that satisfies the far-field condition, and set its coordinates as (0,y). B The first element is the element in the phased array antenna that is furthest from the center point of the array surface.

[0045] If the distance y between the spatial target A and the center point O of the array is... A The distance between spatial target A and the first array element is L. 1A The distance difference ΔL between them 1A If the following formula is satisfied, then space target A is considered to satisfy the far-field condition:

[0046]

[0047] If the distance y between the virtual target B and the center point O of the array is... B The distance between the virtual target B and the first array element is L. 1B The distance difference ΔL between them 1BVirtual target B is considered to satisfy the far-field condition if it meets the following formula:

[0048]

[0049] In one embodiment of this application, when the phased array antenna is a spherical phased array, a virtual target that satisfies the far-field conditions is selected from the far field, and the coordinates of the virtual target in the spherical phased array coordinate system are calculated; based on the distance from the central element of the spherical phased array to the virtual target, and the distance from the coordinates of any element on the spherical phased array to the virtual target, the path difference between the central element and any element is obtained; based on the path difference, the equivalent spatial weighted phase of any element is obtained.

[0050] In one embodiment of this application, when the phased array antenna is a spherical phased array, when the distance from the space target to the center of the spherical phased array is greater than... When the target in space satisfies the far-field condition, r is the array radius of the spherical phased array, and f A is the maximum frequency point for the phased array to receive signals, and c is the speed of light; the first element is an element in a spherical phased array antenna whose distance from the center point of the array is the radius of the array.

[0051] In one embodiment of this application, calculating the coordinates of the virtual target in the spherical phased array coordinate system includes:

[0052] In a spherical phased array antenna, establish a three-dimensional coordinate system with the center of the sphere as the origin. Let the azimuth angle of a space target satisfying the far-field condition in the coordinate system of the spherical array be . pitch angle is Furthermore, the array element on the array surface corresponding to the azimuth and elevation angles is defined as the central array element C, and its coordinates in the coordinate system of the spherical array are set as (x... C ,y C ,z C The coordinates (x, y) of the virtual target B in the spherical coordinate system are obtained according to the following formula. B ,y B ,z B ):

[0053]

[0054] In one embodiment of this application, the distance from the central element of the spherical phased array to the virtual target is calculated according to the following formula:

[0055] The distance L from the central array element C to the virtual target B CB :

[0056]

[0057] In one embodiment of this application, the distance from the coordinates of any element on the spherical phased array to the virtual target is calculated according to the following formula:

[0058] The distance L from any element with coordinates (x1, y1, z1) on the spherical phased array to the virtual target B. 1B :

[0059]

[0060] In one embodiment of this application, the path difference from the central array element to any array element is obtained by the following method:

[0061] Let an arbitrary array element with coordinates (x1, y1, z1) be located at point D on the array surface. Draw a plane α tangent to the spherical surface of the spherical phased array antenna, passing through point C where the central array element is located. Let E be the intersection of plane α and line segment DB. The length of line segment BE is approximately equal to the length of line segment BC. Line segment DE represents the path difference ΔL between the array element with coordinates (x1, y1, z1) and the central array element C. 1C =L 1B -L CB .

[0062] In one embodiment of this application, obtaining the equivalent spatial weighted phase of any array element based on the path difference includes:

[0063] The equivalent spatial weighted phase Δφ of any array element with coordinates (x1, y1, z1) is calculated using the following formula. 1C :

[0064]

[0065] Where c is the speed of light, f A The maximum operating frequency of the phased array antenna is (). Taking the decimal part is for decimal operations.

[0066] For ease of understanding, the present invention provides a more specific embodiment:

[0067] See Figure 1 To illustrate how to determine in engineering terms whether a space target satisfies the far-field condition for a phased array antenna, let's first assume the target lies on the normal line passing through the center point O of the phased array antenna. Figure 1 As shown, with the center point O of the planar phased array antenna as the center point, the line connecting the edge element 1 with the longest distance from the center point O to the center point O is the x-axis, and the normal line passing through the center point O of the planar phased array antenna is the y-axis. In this coordinate system, let the coordinates of the spatial target A be (0, y). AThe coordinates of the center point O of the planar array are (0,0), and the coordinates of the edge element 1 are (x1,0). At this time, the distance between the spatial target A and the center point O of the array is L. 1O The distance between spatial target A and edge element 1 is L. 1A Let L 1A With L OA The distance difference is ΔL 1A Calculate the distance difference ΔL 1A The algorithm is as follows:

[0068]

[0069] As the distance to spatial target A increases, L 1A With L OA The difference ΔL between 1A It will gradually decrease. The decision condition for the far-field condition of space target A is that when the distance difference ΔL 1A When the distance is reduced to a value that does not affect the signal synthesis between the central array element O and the edge array element 1, the far-field condition is satisfied. In engineering implementation, the far-field condition is generally taken as: the distance difference is less than or equal to 1% of the signal wavelength. Applying formula (1) based on this condition, it can be determined whether the space target meets the far-field condition. For example, if the phased array antenna has a radius of 2 meters and the received signal frequency is f... A =3·10 9 Hz, therefore 1% of the signal wavelength is: Meters, where c is the speed of light. Applying formula (1) and substituting x1 = 2, we get:

[0070]

[0071] That is, the far-field condition is met when the distance between target A and the phased array antenna is greater than or equal to two kilometers. Under the condition that the space target meets the far-field condition for the phased array antenna, the signal transmitted by the space target can be regarded as a parallel wave signal for the phased array antenna.

[0072] See Figure 2 This paper uses a planar phased array to illustrate how the weighted phase of a far-field spatial target on the phased array antenna elements is traditionally calculated using path difference. Figure 2 As shown, a plane is formed by the far-field spatial target A, the center point O of the planar phased array antenna, and array element 1. Let θ1 be the angle between the signal path r0 from target A to the center array element O and the line connecting array element 1 to array element O. This angle is the signal incidence angle of target A relative to array element 1. Since spatial target A satisfies the far-field condition for the planar phased array antenna, path r0 and the signal path r1 from spatial target A to array element 1 are parallel. A straight line s perpendicular to r0 is drawn through the center point O of the planar array. This line s is also perpendicular to r1. Let B be the intersection point of line s and r1.

[0073] according to Figure 1 In the analysis, the distance from the far-field target A to the central array element O is approximately equal to the distance from A to point B. Therefore, the path difference of the edge array element 1 is the distance ΔL1 from point B to array element 1. This path difference can be calculated using the coordinates of array element 1 and the signal incident angle θ1 as: ΔL1 = x1·sinθ1. Finally, the spatial weighted phase of the edge array element 1 is calculated using this path difference ΔL1.

[0074] The complexity of this traditional method for solving the path difference of array elements lies in the fact that the signal incident angle θ1 varies for each element on the array surface, requiring individual calculations for each element using a projection method, thus introducing significant complexity. To address this, an improved method for solving the element-weighted phase of a virtual far-field target is proposed.

[0075] See Figure 3 Let's take a planar phased array as an example to illustrate how to calculate the weighted phase of a far-field target on the elements of the phased array antenna using a virtual far-field target method. We'll still first assume that the target lies on the normal line passing through the center point O of the planar phased array antenna surface, such as... Figure 3 As shown, with the center point O of the planar phased array antenna as the center point, the line connecting the edge element 1 with the longest distance from the center point O to the center point O is the x-axis, and the normal line passing through the center point O of the planar phased array antenna is the y-axis. In this coordinate system, let the coordinates of the spatial target A be (0, y). a The coordinates of the center point O of the planar phased array are (0,0), and the coordinates of the edge element 1 are (x1,0). Assume that space target A satisfies the far-field condition for the planar phased array antenna. In this case, arbitrarily imagine a target B satisfying the far-field condition on the y-axis normal passing through the center point O of the array surface, and set its coordinates to (0,y). B ).

[0076] Since the space target A satisfies the far-field condition for the planar phased array antenna, according to formula (1): Similarly, the following can be derived for virtual target B that satisfies the far-field condition: Therefore, we can conclude that:

[0077]

[0078] Therefore, for signal synthesis in a phased array antenna, both the signal transmitted from the far-field virtual target B and the signal transmitted from the far-field target A can be considered as signals parallel to the array surface normal. That is, with the central element as the reference point, the equivalent spatial weighted phase of the array element can be obtained by calculating the path difference of the array element for a virtual target B that satisfies the far-field condition.

[0079] See Figure 4 Similarly, for a spherical phased array antenna, the decision condition given in formula (1) can be used to determine whether a space target satisfies the far-field condition for the spherical phased array antenna. Note that x1 in formula (1) should be replaced with the radius r of the spherical phased array antenna surface. The minimum distance threshold min for the target to satisfy the far-field condition can be calculated. 远场 for:

[0080]

[0081] Where r is the radius of the spherical phased array, f a denoted as the maximum frequency point for the phased array to receive signals, and c as the speed of light.

[0082] like Figure 4 As shown, when a space target satisfies the far-field condition, the signal of the far-field target can be regarded as a parallel wave signal.

[0083] See Figure 5 For spherical phased array antennas, the equivalent spatial weighted phase of each element on the array surface can also be calculated using a virtual far-field target approach for spatial targets that meet the far-field conditions. For example... Figure 5 As shown, a three-dimensional coordinate system with the center of the sphere as the origin is established in the spherical phased array antenna. Let the azimuth angle of the space target satisfying the far-field condition in the coordinate system of the spherical array be . pitch angle is Furthermore, the array element on the array surface corresponding to the azimuth and elevation angles is defined as the central array element C, and its coordinates in the coordinate system of the spherical array are set to (x...). C ,y C ,z C The minimum distance threshold (min) for the far-field conditions of the spherical phased array antenna can be calculated according to formula (3). 远场 And take the distance L from the virtual target B to the center of the spherical phased array antenna. B The far-field condition is satisfied, i.e., L B >min 远场 Therefore, the coordinates (x, y) of the virtual target B in the spherical coordinate system can be obtained using the following algorithm. B ,y B ,z B ):

[0084]

[0085] The distance L from the central array element C to the virtual target B is obtained according to the following algorithm. CB :

[0086]

[0087] And the distance L from any element 1 with coordinates (x1, y1, z1) on the spherical phased array to the virtual target B. 1B :

[0088]

[0089] Let element 1 be located at point D on the array surface, and draw a plane α tangent to the spherical surface of the spherical phased array antenna through point C where the central element is located. Let E be the intersection of plane α and line segment DB. Based on the conclusions analyzed in formula (2), we can obtain that the length of line segment BE is approximately equal to the length of line segment BC, and line segment DE is the path difference between element 1 and the central element C. Therefore, the path difference ΔL between element 1 and the central element C can be obtained. 1C The following algorithm can be used to calculate:

[0090] ΔL 1C =L 1B -L CB (7)

[0091] The path difference ΔL of array element 1 is obtained. 1C Then, the equivalent spatial weighted phase Δφ of array element 1 can be calculated using the following algorithm. 1C :

[0092]

[0093] Here, c is the speed of light, and f is the speed of light. A The maximum operating frequency of the phased array antenna is (). Taking the decimal part is for decimal operations.

[0094] The method presented here for calculating the equivalent spatial weighted phase of phased array antenna elements using virtual far-field targets is applicable not only to planar and spherical phased array antennas, but also to other types of curved phased array antennas. Furthermore, this method is applicable not only to far-field targets, but also to near-field targets with known position information.

[0095] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A method of calculating the far field spatial weighting phase of an element of a phased array antenna, characterized in that, The application relates to a method for calculating the equivalent spatial weighting phase of an arbitrary array element of a phased array antenna. For signal synthesis of the phased array antenna, signals emitted from a far-field virtual target and signals emitted from a far-field actual target are both regarded as signals parallel to the normal line of the array plane of the phased array antenna; that is, for the actual target and the virtual target satisfying the far-field condition, the equivalent spatial weighting phase of an arbitrary array element is obtained by calculating the wave path difference of the signals emitted from the far-field actual target and / or the far-field virtual target to the central array element and any array element other than the central array element of the phased array antenna; When the phased array antenna is a spherical phased array, a virtual target satisfying the far-field condition is selected from the far field, and the coordinate value of the virtual target in the coordinate system of the spherical phased array is calculated; the wave path difference from the central array element to any array element of the spherical phased array is obtained according to the distance from the central array element of the spherical phased array to the virtual target and the distance from the coordinates of any array element of the spherical phased array to the virtual target; The equivalent spatial weighting phase of any array element is obtained according to the wave path difference. The method comprises the following steps: A three-dimensional coordinate system with the spherical center as the origin is established in the spherical phased array antenna, the coordinate value of the virtual target in the three-dimensional coordinate system of the spherical phased array is obtained according to the azimuth angle and the elevation angle of the space target satisfying the far-field condition in the three-dimensional coordinate system of the spherical array, the array element on the array plane corresponding to the azimuth angle and the elevation angle, and the coordinates of the array element in the three-dimensional coordinate system of the spherical phased array; The wave path difference from the central array element to any array element of the spherical phased array is obtained according to the distance from the central array element of the spherical phased array to the virtual target and the distance from the coordinates of any array element of the spherical phased array to the virtual target. The distance from the central array element of the spherical phased array to the virtual target is obtained according to the coordinates of the central array element of the spherical phased array and the coordinates of the virtual target; the central array element is the array element on the array plane corresponding to the azimuth angle and the elevation angle. The distance from the coordinates of any array element of the spherical phased array to the virtual target is obtained according to the coordinates of any array element of the spherical phased array and the coordinates of the virtual target. The wave path difference from the central array element to any array element of the spherical phased array is the difference between the distance from the coordinates of any array element of the spherical phased array to the virtual target and the distance from the central array element of the spherical phased array to the virtual target. The equivalent spatial weighting phase of any array element is obtained according to the wave path difference from the central array element to any array element and the maximum frequency point at which the phased array antenna works. The distance from the central array element of the spherical phased array to the virtual target is calculated according to the following formula: When the phased array antenna is a spherical phased array, when the distance from a space target to the center of the spherical phased array is greater than , the space target satisfies the far field condition; wherein, r is the radius of the array surface of the spherical phased array, f A is the maximum frequency point of the phased array received signal, c is the speed of light; and the first array element is an array element in the spherical phased array antenna with a distance from the center point of the array surface to the array element being the radius of the array surface.

2. The method of claim 1, wherein, The distance from the coordinates of any array element of the spherical phased array to the virtual target is calculated according to the following formula: In the spherical phased array antenna, a three-dimensional coordinate system is established with the sphere center as the origin, and the azimuth angle of a spatial target satisfying the far field condition in the coordinate system of the spherical array is the elevation angle is and the array element on the array surface corresponding to the azimuth angle and the elevation angle is defined as the center array element C and its coordinates in the coordinate system of the spherical array are (x C ,y C ,z C ), and the coordinate values (x B ,y B ,z B ) of the virtual target B in the coordinate system of the spherical array are obtained according to the following formula: where L B is the distance from the virtual target B to the sphere center of the spherical phased array antenna.

3. The method of claim 2, wherein, The wave path difference from the central array element to any array element is obtained by the following method: The distance L of the central array element C to the virtual target B CB :

4. The method of claim 3, wherein, The equivalent spatial weighting phase of any array element is obtained according to the wave path difference from the central array element to any array element. The distance L from the array element with arbitrary coordinates (x1, y1, z1) on the spherical phased array to the virtual target B 1B :

5. The method of claim 3, wherein, ​ The point D of the array element with coordinates (x1, y1, z1) is on the array surface, a plane α tangent to the spherical surface of the spherical phased array antenna is drawn through the point C where the central array element is located, and the intersection of the plane α and the line segment DB is E; the length of the line segment BE is approximately equal to the length of the line segment BC, and the line segment DE is the wave path difference ΔL of the array element with coordinates (x1, y1, z1) and the central array element C 1C = L 1B -L CB , L 1B is the distance from the array element with coordinates (x1, y1, z1) on the spherical phased array to the virtual target B.

6. The method of claim 5, wherein, ​ The equivalent spatial weighted phase Δφ of an arbitrary element with coordinates (x1, y1, z1) is calculated according to the following formula 1C : Wherein, c is the speed of light, f A is the maximum frequency point of the phased array antenna, and the decimal is a decimal operation.

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