Self-organizing generation method of freeform conformal antenna array

Abstract

The application provides a free curved surface conformal antenna array self-organizing generation method, which comprises the following steps: generating a target curved surface; generating a random point set on the target curved surface and under the grid constraint; connecting anchor points with each random point to generate a connecting line under the point anchor constraint; performing length constraint on the length of the connecting line; performing collision constraint on the distance between each random point; inputting a momentum optimization solver to optimize the random points; finding the nearest points of the optimized random points on the target curved surface; taking the working planes of the optimized random points on the target curved surface; generating circular array elements based on each working plane and projecting each working plane to the target curved surface in the normal direction to form a final conformal antenna array pattern. The application can randomly attach array elements to a curved surface without being limited by the shape of the curved surface, can uniformly arrange the array elements on the curved surface in a self-organizing manner, significantly improves the consistency of the array element spacing and the array element area, and can be widely applied to the conformal antenna array field.

Description

Technical Field

[0001] This invention relates to the field of conformal antenna array technology, and more specifically, to a method for self-organizing and generating freeform surface conformal antenna arrays. Background Technology

[0002] The shape of products such as high-speed trains, airplanes, and ships is usually determined by non-electrical factors such as aerodynamics and mechanics, and is generally difficult to change. Conformal antenna arrays, however, can maintain a high degree of consistency with the surface shape of these products, minimizing changes to the product's shape, and have therefore gained widespread application. The surface on which conformal antenna arrays are arranged is typically a free-form surface. Considering the need to avoid grating lobe formation, the size, shape, and spacing of individual array elements on the surface need to be as consistent as possible. How to generate conformal antenna arrays that meet these requirements on free-form surfaces is a pressing problem that needs to be solved.

[0003] Typical methods for generating conformal antenna arrays include: 1) using the wrapping surface and surface flow methods in industrial design software to first generate the antenna array on plane A, and then using the one-to-one correspondence between u and v construction lines on plane A and the projected surface B to deform the conformal antenna array onto the projected surface; 2) using the sketch projection function in industrial design software to generate the antenna array on the projected surface along the normal or a specific direction; 3) using the slicing method to slice the free surface along a specific curve at a certain interval, extract the intersection line between the slice and the surface, divide the intersection line at equal intervals according to a specific offset angle and length, and arrange the array elements in sequence.

[0004] Method 1) Taking patents 202110832467.2 and 201811199726.7 as examples, the former mainly calculates the array antenna arrangement based on the planar array corresponding to the surface area of ​​the curved surface. The selected curved surface is a uniform spherical surface, and only a planar array with a surface area equivalent to that of the sphere is selected. The spherical surface is a typical non-developable curved surface. The latter also mentions setting the two-dimensional dimensions of each curved surface grid to correspond to the spacing of the planar array elements. However, when a non-developable curved surface is unfolded into a plane, its area distortion is usually large, which cannot be ignored in the design of the antenna array elements. It can be seen from its deployment results that its curved antenna pattern has obvious spacing distortion, which makes it difficult to meet the requirement of equal spacing of the array, and the design of the feeding system is also more complicated.

[0005] Method 2) has the following problems: When using the projection method, the shape of the sketch must be determined in advance, which has poor adaptability. At the same time, for non-developable curved surfaces with large curvature, the shape and spacing of the array elements also vary greatly.

[0006] Method 3), taking patent 202110218149.7 as an example, targets a parameterized hyperboloid radome. It divides the radome along the generatrix direction into several rings according to the period length using the generatrix equation, and equates each ring to a conical surface. The radius of the smaller and larger circles is calculated using the generatrix formula. Finally, the circumference of the conical surface is used to equally divide the elements, establishing a local coordinate system and projecting it. This method is mainly applicable to planes with known analytical expressions. For irregular free-form surfaces, it is difficult to obtain the surface analytical expression to calculate the spacing of the slices and the angle of offset between adjacent intersection lines. Furthermore, the length of the intersection lines is difficult to divide according to the element size and spacing requirements. Overall, this method is only suitable for relatively regular free-form surfaces. Summary of the Invention

[0007] This invention aims to provide a self-organizing generation method for freeform surface conformal antenna arrays. Addressing the requirement for uniform arraying of freeform surface conformal antennas, it employs an array element self-organization method, applying collision constraints and line segment length constraints to each array element, and utilizing momentum optimization to effectively improve the consistency of area and spacing of array elements when arranged on freeform surfaces. This avoids the significant changes in distance and position that occur when arranging antenna elements on non-developable surfaces using traditional methods, and the resulting degradation in radiation performance.

[0008] This invention provides a self-organizing method for generating a freeform surface conformal antenna array, comprising the following steps:

[0009] S1, generate the target surface;

[0010] S2 generates a set of random points on the target surface;

[0011] S3, apply grid constraints to the random point set to ensure that the random point set lies on the target surface;

[0012] S4. Select an anchor point outside the target surface. After point anchoring constraint, connect the anchor point with each random point to generate a connection line.

[0013] S5, apply length constraints to all connections;

[0014] S6, apply collision constraints to the distances between random points;

[0015] S7 will input the momentum optimization solver with mesh constraints, point anchoring constraints, length constraints, and collision constraints to optimize random points;

[0016] S8 uses the nearest neighbor operation on the surface to obtain the nearest neighbor of the optimized random point on the target surface;

[0017] S9, based on the nearest neighbor point and using the evaluation surface operation, obtains the optimized working plane of the random point on the target surface;

[0018] S10, based on each working plane, generates circular array elements with the optimized random points as the origin;

[0019] S11, project each circular array element onto the target curved surface according to the normal of each working plane to form the final conformal antenna array pattern.

[0020] Furthermore, step S2 is as follows:

[0021] A random point set is generated on the target surface using a random point generation tool; the number of random points in the random point set is the same as the number of array elements required.

[0022] Furthermore, in step S4, an anchor point is selected outside the target surface near the array element deployment area.

[0023] Furthermore, step S5 is as follows:

[0024] Set a target length value and attraction value for all connecting lines to complete the length constraint.

[0025] Furthermore, step S6 is as follows:

[0026] To prevent grating lobes from being generated in a conformal antenna array, a circular collision constraint radius and a repulsion force are set between each random point to complete the collision constraint.

[0027] Furthermore, in step S9, the working plane refers to:

[0028] The plane that is tangent to the target surface by the optimized random point.

[0029] Furthermore, in step S10, the radius of the circular array element is equal to the required array element spacing.

[0030] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0031] Compared to existing conformal antenna array generation methods, this invention is not limited by the shape of the surface and can randomly attach array elements to the surface. By employing constraints such as mesh constraints, point anchoring constraints, length constraints, and collision constraints, and using a momentum optimization solver, the array elements can be uniformly arranged on the surface in a self-organizing manner, which significantly improves the consistency of array element spacing and array element area. It can be widely applied in the field of conformal antenna arrays. Attached Figure Description

[0032] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 This is a flowchart of the self-organizing generation method for free-form surface conformal antenna arrays in an embodiment of the present invention.

[0034] Figure 2 This is a schematic diagram illustrating the generation of random points on a freeform surface in an embodiment of the present invention.

[0035] Figure 3 This is a schematic diagram of the line connecting the anchor point and the random point in an embodiment of the present invention.

[0036] Figure 4 This is a schematic diagram illustrating the optimization of random points in an embodiment of the present invention.

[0037] Figure 5 This is a schematic diagram of generating the working plane in an embodiment of the present invention.

[0038] Figure 6 This is a schematic diagram of generating a conformal antenna array pattern in an embodiment of the present invention. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0040] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0041] Example

[0042] like Figure 1 As shown, this embodiment proposes a self-organizing generation method for freeform surface conformal antenna arrays, including:

[0043] S1, Generate the target surface. In this embodiment, a typical non-developable surface, a parabola, is generated.

[0044] S2, Use a random point generation tool to generate a set of random points on the target surface; the number of random points in the set of random points is the same as the number of required array elements, and in this embodiment the number of random points is 44.

[0045] S3 applies a grid constraint to the random point set to ensure that the random point set lies on the target surface, such as... Figure 2 As shown;

[0046] S4, select an anchor point F near the array element deployment area outside the target surface. After point anchoring constraints, connect the anchor point with each random point to generate a connection line, such as... Figure 3 As shown;

[0047] S5, set a target length value of 50 and an attraction force of 0.001 for all connection lengths to complete the length constraint;

[0048] S6. In accordance with the requirement of conformal antenna array to prevent grating lobe generation, a circular collision constraint radius of 4.8 and a repulsive force of 21 are set between each random point to complete the collision constraint.

[0049] It should be noted that attraction and repulsion are dimensionless parameters used in the Grasshopper physics engine to express the magnitude of force.

[0050] S7 will input mesh constraints, point anchoring constraints, length constraints, and collision constraints into the momentum optimization solver, iterating step by step until convergence to achieve a uniform distribution of the point cloud, thereby optimizing random points, such as... Figure 4 As shown;

[0051] S8 uses the nearest neighbor operation on the surface to obtain the nearest neighbor of the optimized random point on the target surface;

[0052] S9, based on the nearest neighbor point and using the evaluation surface operation, obtains the optimized work plane of the random point on the target surface, such as... Figure 5 As shown;

[0053] S10, Based on each working plane, generate circular array elements with the optimized random points as the origin, wherein the radius of the circular array elements is equal to the required array element spacing;

[0054] S11, project each circular array element onto the target surface according to the normal of each working plane, forming the final conformal antenna array pattern, such as... Figure 6 As shown, this can maximize the spacing and uniformity of the conformal antenna array pattern area.

[0055] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for self-organizing and generating a freeform surface conformal antenna array, characterized in that, Includes the following steps: S1, generate the target surface; S2 generates a set of random points on the target surface; S3, apply grid constraints to the random point set to ensure that the random point set lies on the target surface; S4. Select an anchor point outside the target surface. After point anchoring constraint, connect the anchor point with each random point to generate a connection line. S5, apply length constraints to all connections; S6, apply collision constraints to the distances between random points; S7 will input the momentum optimization solver with mesh constraints, point anchoring constraints, length constraints, and collision constraints to optimize random points; S8 uses the nearest neighbor operation on the surface to obtain the nearest neighbor of the optimized random point on the target surface; S9, based on the nearest neighbor point and using the evaluation surface operation, obtains the optimized working plane of the random point on the target surface; S10, based on each working plane, generates circular array elements with the optimized random points as the origin; S11, project each circular array element onto the target curved surface according to the normal of each working plane to form the final conformal antenna array pattern.

2. The self-organizing generation method for freeform surface conformal antenna arrays according to claim 1, characterized in that, Step S2 is as follows: A random point set is generated on the target surface using a random point generation tool; the number of random points in the random point set is the same as the number of array elements required.

3. The self-organizing generation method for freeform surface conformal antenna arrays according to claim 1, characterized in that, In step S4, an anchor point is selected outside the target surface near the array element deployment area.

4. The self-organizing generation method for freeform surface conformal antenna arrays according to claim 1, characterized in that, Step S5 is as follows: Set a target length value and attraction value for all connecting lines to complete the length constraint.

5. The self-organizing generation method for freeform surface conformal antenna arrays according to claim 1, characterized in that, Step S6 is: To prevent grating lobes from being generated in a conformal antenna array, a circular collision constraint radius and a repulsion force are set between each random point to complete the collision constraint.

6. The self-organizing generation method for freeform surface conformal antenna arrays according to claim 1, characterized in that, In step S9, the working plane refers to: The plane that is tangent to the target surface by the optimized random point.

7. The self-organizing generation method for freeform surface conformal antenna arrays according to claim 1, characterized in that, In step S10, the radius of the circular array element is equal to the required array element spacing.

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