Fast judgment method and device for adjacent boundary elements of periodic structure grid model

Abstract

The application discloses a kind of periodical structure grid model adjacent boundary unit fast judging method and its device, method includes: applied to the electromagnetic field periodical structure grid model of non-conformal, the model includes several tetrahedron structures, corresponding method includes: with the average edge length calculated according to all tetrahedron structures as division interval, the space region range formed by all tetrahedron structures in electromagnetic field periodical structure grid model is divided to obtain several virtual boxes;According to the four vertices of each tetrahedron structure in the four vertices of the tetrahedron structure, determine the boundary unit structure;According to the center coordinates of each boundary unit structure, the boundary unit structure is mapped into corresponding virtual box;For each boundary unit structure, calculate the number of the boundary unit structure in virtual box, find the adjacent boundary unit structure corresponding to the number in virtual box.The application realizes the fast judging of adjacent boundary unit in the electromagnetic field periodical structure grid model of non-conformal.

Description

Technical Field

[0001] This invention belongs to the field of electromagnetic field signal processing technology, specifically relating to a method and apparatus for rapidly determining adjacent boundary elements in a periodic structure grid model. Background Technology

[0002] A periodic mesh model is composed of individual resonant elements arranged in a specific spatial configuration within an electromagnetic field. Periodic mesh models are array-type structures with numerous variations, such as photonic bandgap structures, phased array antennas, electromagnetic bandgap structures, and novel left- / right-handed electromagnetic materials. Similar to filters, periodic mesh models exhibit specific passband and stopband characteristics for electromagnetic waves, and also demonstrate excellent selectivity in the transmission, reflection, and absorption of electromagnetic waves.

[0003] In engineering applications, a periodic structured mesh model can be viewed as a two-dimensional periodic structured mesh model, with periodic boundaries applied to all four sides, i.e., as shown below. Figure 1 (a) shows that the left and right boundaries and the top and bottom boundaries are symmetrical and regular conformal mesh models. In such periodic structure mesh models, it is relatively easy to determine the adjacent boundary cells. For example, the existing exhaustive search method and volume point matrix method can quickly find the structure of adjacent boundary cells based on the symmetry and regularity of the left and right and the top and bottom boundaries.

[0004] However, for such Figure 1 (b) shows that the left and right and / or top and bottom boundaries are asymmetric, irregular, and non-conformal mesh models. If the existing exhaustive method is used, for example, to determine a certain tetrahedral structure on the left, all the corresponding tetrahedral structures on the right need to be determined. Similarly, to determine the right, the left needs to be traversed. Although it is easy to implement, it is computationally intensive and inefficient. The volume point matrix method cannot be used for non-conformal meshes at all; it can only be used to determine adjacent elements of conformal meshes. Summary of the Invention

[0005] To address the aforementioned problems in the existing technology, this invention provides a method and apparatus for rapidly determining adjacent boundary elements in a periodic structure mesh model.

[0006] In a first aspect, embodiments of the present invention provide a method for rapidly determining adjacent boundary elements in a periodic structure mesh model. This method is applied to electromagnetic field periodic structure mesh models where the left and right boundaries and / or the top and bottom boundaries are non-conformal. The electromagnetic field periodic structure mesh model includes several tetrahedral structures, and the corresponding method includes:

[0007] Calculate the average edge length based on all tetrahedral structures;

[0008] Using the average edge length as the dividing interval, the spatial region formed by all tetrahedral structures in the electromagnetic field periodic structure grid model is divided to obtain several virtual boxes.

[0009] The boundary element structure is determined based on the coordinate values ​​of the four vertices that constitute the tetrahedral structure.

[0010] Calculate the center coordinates of each boundary element structure;

[0011] Each boundary unit structure is mapped to a corresponding virtual box based on the center coordinates; wherein each virtual box corresponds to a number;

[0012] For each boundary element structure, calculate its number in the virtual box, determine if there is a virtual box corresponding to that number, and if so, search for the adjacent boundary element structure corresponding to that number in the virtual box.

[0013] In one embodiment of the present invention, calculating the center coordinates of each boundary element structure includes:

[0014] Calculate the coordinates of the four vertices of each boundary unit structure in a three-dimensional orthogonal Cartesian coordinate system;

[0015] The average of the coordinates of the four vertices is used as the center coordinates of the corresponding boundary unit structure.

[0016] In one embodiment of the present invention, mapping each boundary unit structure to a corresponding virtual box according to the center coordinates includes:

[0017] Calculate the number of each boundary unit structure mapped to the virtual box based on the center coordinates and the average edge length, and map each boundary unit structure to the virtual box with the corresponding number.

[0018] In one embodiment of the present invention, calculating the number of the boundary unit structure in the virtual box includes:

[0019] Obtain the first coordinate value corresponding to the boundary element structure in the electromagnetic field periodic structure mesh model; wherein, for the left and right boundaries, the first coordinate value includes the upper or lower y-axis coordinate of the boundary element structure, and for the upper and lower boundaries, the first coordinate value includes the upper or lower x-axis coordinate of the boundary element structure.

[0020] The number of the boundary unit structure in the virtual box is calculated based on the first coordinate value and the average edge length.

[0021] In one embodiment of the present invention, finding the adjacent boundary unit structure corresponding to the number in the virtual box includes:

[0022] The corresponding second coordinate value is obtained based on the first coordinate value; wherein, for the left and right boundaries, the second coordinate value includes the lower limit coordinate of the y-axis or the upper limit coordinate of the y-axis corresponding to the boundary unit structure in the same row as the boundary unit structure; for the upper and lower boundaries, the first coordinate value includes the lower limit coordinate of the x-axis or the upper limit coordinate of the x-axis corresponding to the boundary unit structure in the same column as the boundary unit structure.

[0023] Calculate the number of the boundary unit structures in the virtual box that are in the same row or column based on the second coordinate value and the average edge length;

[0024] The center coordinates of the boundary unit structures in the same row or column in the virtual box are calculated based on their numbers and the average edge length. The corresponding adjacent boundary unit structures are then located based on these center coordinates.

[0025] In one embodiment of the present invention, the corresponding method further includes:

[0026] Based on the adjacent boundary unit structure, other boundary unit structures adjacent to the adjacent boundary unit structure are determined.

[0027] In one embodiment of the present invention, the corresponding method further includes:

[0028] The polygonal overlapping region is calculated based on the adjacent boundary unit structure and other boundary unit structures adjacent to the adjacent boundary structure. The polygonal overlapping region is used by the electromagnetic field numerical algorithm to calculate the periodic structure of the electromagnetic field.

[0029] Secondly, embodiments of the present invention provide a device for rapidly determining adjacent boundary elements of a periodic structure mesh model, characterized in that it is applied to an electromagnetic field periodic structure mesh model in which the left and right boundaries and / or the top and bottom boundaries are non-conformal, wherein the electromagnetic field periodic structure mesh model includes a plurality of tetrahedral structures, and the device includes:

[0030] The first calculation unit is used to calculate the average edge length based on all tetrahedral structures;

[0031] The partitioning unit is used to divide the spatial region formed by all tetrahedral structures in the electromagnetic field periodic structure grid model into several virtual boxes, with the average edge length as the partitioning interval.

[0032] The first determining unit is used to determine the boundary unit structure based on the coordinate values ​​of the four vertices constituting the tetrahedral structure in each tetrahedral structure.

[0033] The second calculation unit is used to calculate the center coordinates of each boundary unit structure;

[0034] A mapping unit is used to map each boundary unit structure to a corresponding virtual box according to the center coordinates; wherein each virtual box corresponds to a number;

[0035] The lookup unit is used to calculate the number of each boundary unit structure in the virtual box, determine whether there is a virtual box corresponding to the number, and if so, search for the adjacent boundary unit structure corresponding to the number in the virtual box.

[0036] In one embodiment of the present invention, the corresponding device further includes:

[0037] The second determining unit is used to determine other boundary unit structures adjacent to the adjacent boundary unit structure based on the adjacent boundary unit structure.

[0038] In one embodiment of the present invention, the corresponding device further includes:

[0039] The third calculation unit is used to calculate the polygonal overlapping region based on the adjacent boundary unit structure and other boundary unit structures adjacent to the adjacent boundary structure. The polygonal overlapping region is used by the electromagnetic field numerical algorithm to calculate the periodic structure of the electromagnetic field.

[0040] The beneficial effects of this invention are:

[0041] This invention proposes a method for rapidly determining adjacent boundary elements in a periodic structure mesh model, offering a novel approach to spatial box mapping: The spatial region formed by all tetrahedral structures in the electromagnetic field periodic structure mesh model is divided into several virtual boxes. All virtual boxes constitute a cubic mesh structure. Boundary element structures are determined from all tetrahedral structures, and the center coordinates of each boundary element structure are calculated. Based on these center coordinates, all boundary element structures are mapped to their corresponding numbered virtual boxes. Subsequently, for any boundary element structure, only the number of the boundary element and its corresponding virtual box needs to be calculated first, and then the adjacent boundary element structure corresponding to that number is searched within the virtual boxes. Therefore, the spatial box mapping method proposed in this invention, for electromagnetic field periodic structure mesh models with non-conformal left and right boundaries and / or top and bottom boundaries, significantly reduces the search depth and improves computational efficiency compared to existing exhaustive methods.

[0042] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0043] Figure 1 (a)~ Figure 1 (b) is a schematic diagram of the periodic structure mesh in the electromagnetic field periodic structure mesh model, showing both conformal and non-conformal structures;

[0044] Figure 2This is a flowchart illustrating a method for quickly determining adjacent boundary elements in a periodic structure mesh model, as provided in an embodiment of the present invention.

[0045] Figure 3 This is a schematic diagram of the boundary unit structure provided in the embodiment of the present invention mapped to the corresponding virtual box;

[0046] Figure 4 This is a schematic diagram of a polygonal overlapping region formed by two boundary unit structures provided in an embodiment of the present invention;

[0047] Figure 5 (a)~ Figure 5 (b) is a schematic diagram of the calculation time of the method of the present invention and the exhaustive method for different numbers of tetrahedrons;

[0048] Figure 6 This is a schematic diagram of a device for quickly determining adjacent boundary elements in a periodic mesh model, provided in an embodiment of the present invention.

[0049] Figure 7 This is a schematic diagram of another device for quickly determining adjacent boundary elements in a periodic mesh model provided in an embodiment of the present invention.

[0050] Figure 8 This is a schematic diagram of another device for quickly determining adjacent boundary elements in a periodic structure mesh model provided in this embodiment of the invention;

[0051] Figure 9 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0052] The present invention will be further described in detail below with reference to specific embodiments, but the implementation of the present invention is not limited thereto.

[0053] The inventors discovered that the exhaustive search method is extremely inefficient because it identifies many tetrahedral structures that are not adjacent to or are far from the n-th tetrahedron. These useless tetrahedral structures negatively impact the overall computation speed. Therefore, to eliminate the identification of useless tetrahedral structures, the fundamental approach is to select several adjacent tetrahedral structures surrounding the n-th tetrahedron. These adjacent tetrahedral structures have a certain distance limit from the n-th tetrahedron. This way, when extracting common face information, traversing these adjacent tetrahedral structures reduces computational resource consumption. However, quickly selecting these adjacent tetrahedral structures is crucial. Traversing all tetrahedral structures to determine if the distance limit is met is impractical, as this would revert to the exhaustive search method. To quickly select adjacent tetrahedral structures, this invention proposes a novel approach. Utilizing the concept of a cubic mesh, the spatial region formed by all tetrahedral structures in the electromagnetic field periodic structure mesh model is divided into several virtual boxes. These virtual boxes constitute a cubic mesh structure. By employing a spatial box-projection method, rapid identification of adjacent boundary elements is achieved in a non-conformal mesh. Specifically: Please refer to... Figure 2 This invention provides a method for quickly determining adjacent boundary elements in a periodic structure mesh model. This method is applied to electromagnetic field periodic structure mesh models where the left and right boundaries and / or the top and bottom boundaries are non-conformal. The electromagnetic field periodic structure mesh model includes several tetrahedral structures. The corresponding method includes:

[0054] S10. Calculate the average edge length based on all tetrahedral structures.

[0055] An embodiment of the present invention provides an optional solution: each tetrahedral structure has six edges, and the average value of all edges of all tetrahedral structures is used as the average edge length.

[0056] S20. Using the average edge length as the dividing interval, the spatial region formed by all tetrahedral structures in the electromagnetic field periodic structure grid model is divided to obtain several virtual boxes.

[0057] The electromagnetic field periodic structure grid model is a cubic structure composed of several tetrahedral structures. The spatial region formed by all tetrahedral structures is divided into several virtual boxes with the average edge length as the dividing interval. Each virtual box contains a tetrahedral structure.

[0058] For example, if the spatial region formed by all tetrahedral structures is (-0.3 to 0.3), and the average edge length calculated by S10 is 0.2, then the spatial region of (-0.3 to 0.3) can be divided into three virtual boxes: (-0.3 to -0.1), (-0.1 to 0.1), and (0.1 to 0.3).

[0059] S30. Determine the boundary unit structure based on the coordinate values ​​of the four vertices that constitute the tetrahedral structure in each tetrahedral structure.

[0060] Since the electromagnetic field periodic structure mesh model only needs to process its boundary element structure, which refers to a tetrahedral structure whose face is located on the boundary, this embodiment of the invention provides an optional solution: determining whether the tetrahedral structure is a boundary element structure by using the coordinate values ​​of the four vertices constituting the tetrahedral structure. Specifically, if the coordinate values ​​of at least three of the four vertices are located on the boundary of the electromagnetic field periodic structure mesh model, then the tetrahedral structure is considered a boundary element structure. The coordinate values ​​of the four vertices of the tetrahedral structure are in a three-dimensional orthogonal Cartesian coordinate system.

[0061] S40. Calculate the center coordinates of each boundary unit structure.

[0062] This invention provides an optional approach to calculate the center coordinates of each boundary unit structure, including: calculating the coordinate values ​​of the four vertices of each boundary unit structure in a three-dimensional orthogonal Cartesian coordinate system; and using the average of the coordinate values ​​of the four vertices as the center coordinates of the corresponding boundary unit structure. Here, the center coordinates include the center coordinate values ​​corresponding to the x, y, and z axes. For example, the average of the coordinate values ​​of the four vertices in the x-axis direction is calculated as the center coordinate value corresponding to the x-axis; similarly, the average of the coordinate values ​​of the four vertices in the y-axis direction is calculated as the center coordinate value corresponding to the y-axis, and the average of the coordinate values ​​of the four vertices in the z-axis direction is calculated as the center coordinate value corresponding to the z-axis.

[0063] It is evident that the focus during the search for adjacent boundary elements is on the boundary element structure. For each boundary element structure, the coordinates of the four vertices of each boundary element structure are calculated using the method for calculating each tetrahedral structure in S30. The average of the coordinates of the four vertices is used as the center coordinates of the corresponding boundary element structure. It can be seen that the center coordinates of each boundary element structure are different.

[0064] S50. Map each boundary unit structure to the corresponding virtual box according to the center coordinates; where each virtual box corresponds to a number;

[0065] Since exhaustive enumeration of all boundary unit structures is inefficient, this invention provides an alternative solution: using a spatial box mapping method, each boundary unit structure is mapped to a corresponding virtual box. One or more adjacent boundary unit structures surrounding a given boundary unit structure are selected through this virtual box, eliminating the need to traverse all boundary unit structures. Specifically:

[0066] Mapping each boundary unit structure to its corresponding virtual box based on its center coordinates involves: calculating the virtual box number for each boundary unit structure based on its center coordinates and average edge length; mapping each boundary unit structure to the corresponding numbered virtual box; and representing the virtual box number as floor(center coordinates / average edge length), where floor represents the floor function. The center coordinates can be the center coordinate values ​​corresponding to the x, y, and z axes. Therefore, the calculated virtual box number includes the numbers corresponding to the x, y, and z axes, denoted as (I, J, K), where I represents the number corresponding to the x-axis, J represents the number corresponding to the y-axis, and K represents the number corresponding to the z-axis. Since the center coordinates of each boundary unit structure are different, the calculated virtual box number is also different; each virtual box corresponds to a number, and each number is an integer. It can be seen that the geometric relationship of each virtual box is clear, which can play a good auxiliary role in subsequent search and judgment processes.

[0067] For example, if S40 calculates that the center coordinate of the x-axis of a certain boundary element structure is 0.25 and the average edge length is 0.2, then floor(0.25 / 0.2) = 0, which means that the virtual box number corresponding to the x-axis direction of this boundary element structure is 0; the calculation method for the virtual box numbers corresponding to other axes of this boundary element structure, as well as the virtual box numbers corresponding to other boundary element structures, is similar.

[0068] for example Figure 3 This diagram illustrates how two adjacent boundary element structures are mapped to their corresponding virtual boxes. The left side represents boundary element structure e1, and the right side represents boundary element structure e2. f1 represents the face (triangle) of the single boundary element structure e1 on its boundary, and f2 represents the face (triangle) of the right boundary element structure e2 on its right boundary. The center coordinates of boundary element structures e1 and e2 are used to assign them the corresponding virtual box numbers (I, J1, K) and (I, J2, K). When searching for adjacent boundary element structures, knowing the virtual box number (I, J1, K) of boundary element structure e1 allows us to find its adjacent boundary element structure e2; and vice versa.

[0069] S60. For each boundary element structure, calculate the number of the boundary element structure in the virtual box, determine whether there is a virtual box corresponding to the number, and if so, search for the adjacent boundary element structure corresponding to the number in the virtual box.

[0070] After mapping all boundary cell structures to virtual boxes, how can we quickly find the adjacent boundary cell structures corresponding to each boundary cell structure? The inventors discovered that since all boundary cell structures are mapped to virtual boxes representing the boundary distribution, for a boundary cell structure on the left, its corresponding adjacent boundary cell structure on the right is determined. The right-side adjacent boundary cell structure is determined using the partitioned virtual boxes, thus reducing the search depth, decreasing computational load, and improving search efficiency. Specifically:

[0071] For non-conformal electromagnetic field periodic structure mesh models, the left and right boundaries and / or the top and bottom boundaries are asymmetric and irregular. However, the coordinate values ​​of the boundary element structures distributed on the left and right boundaries and / or the top and bottom boundaries can be calculated in a three-dimensional orthogonal Cartesian coordinate system. Thus, the maximum and minimum values ​​corresponding to all boundary element structures in the left and right boundaries, i.e., the upper or lower y-axis coordinates, and the maximum and minimum values ​​corresponding to all boundary element structures in the top and bottom boundaries, i.e., the upper or lower x-axis coordinates, can be known in advance.

[0072] For each boundary element structure, this embodiment of the invention provides an optional approach, firstly calculating the number of the boundary element structure in the virtual box, including:

[0073] For a boundary element structure on the left or right boundary, obtain the first coordinate value corresponding to the boundary element structure in the electromagnetic field periodic structure mesh model. The first coordinate value includes the upper or lower y-axis coordinate of the boundary element structure. If the boundary element structure is located on the left boundary, the first coordinate value includes the upper y-axis coordinate of the boundary element structure. In this case, the adjacent boundary element structure corresponding to the right boundary will be searched from the left boundary. If the boundary element structure is located on the right boundary, the first coordinate value includes the lower y-axis coordinate of the boundary element structure. In this case, the adjacent boundary element structure corresponding to the left boundary will be searched from the right boundary.

[0074] Similarly, for a certain boundary element structure on the upper and lower boundaries, the first coordinate value corresponding to the boundary element structure in the electromagnetic field periodic structure mesh model is obtained. The first coordinate value includes the upper or lower x-axis coordinate of the boundary element structure. If the boundary element structure is located on the upper boundary, the first coordinate value includes the lower x-axis coordinate of the boundary element structure. At this time, the corresponding adjacent boundary element structure in the lower boundary will be searched from the upper boundary. If the boundary element structure is located on the lower boundary, the first coordinate value includes the upper x-axis coordinate of the boundary element structure. At this time, the corresponding adjacent boundary element structure in the upper boundary will be searched from the lower boundary.

[0075] Further, the number of the boundary element structure in the virtual box is calculated based on the first coordinate value and the average edge length. Specifically:

[0076] For a boundary element structure on the left or right boundary, having obtained the first coordinate value corresponding to this boundary element structure in the electromagnetic field periodic structure mesh model, the number of this boundary element structure in the virtual box can be calculated based on the first coordinate value and the average edge length, and can be represented as floor(first coordinate value / average edge length). For the boundary element structure on the left boundary, the first coordinate value includes the lower y-axis coordinate. min For the boundary element structure on the right boundary, the first coordinate value includes the upper limit coordinate of the y-axis. max For example, in a boundary cell structure with a certain left boundary, the first coordinate value along the y-axis is the lower y-axis coordinate. min =0.29, the average edge length is 0.2, and the boundary element structure corresponds to the floor(0.29 / 0.2)=1 in the y-axis direction of the virtual box, denoted as (I, J1, K). I and K are variable, and the cycle of I and K corresponds to the left and back sides of a face. The calculation of I and K is the same as the method of calculating the number I and K in S50 using the center coordinate values ​​of the x and z directions (i.e. the first coordinate values ​​of the x and z axes at this time), which will not be repeated here. Other boundary element structures in the same row as this boundary element structure are located on the right boundary.

[0077] Similarly, for a boundary element structure at the upper or lower boundary, having already obtained the first coordinate value corresponding to that boundary element structure in the electromagnetic field periodic structure mesh model, the number of that boundary element structure in the virtual box, calculated based on the first coordinate value and the average edge length, can be represented as floor(first coordinate value / average edge length). For the boundary element structure at the lower boundary, the first coordinate value includes the lower x-axis coordinate. min For the boundary unit structure at the upper boundary, the first coordinate value includes the upper x-axis coordinate x. max For example, in a boundary element structure at a certain lower boundary, the first coordinate in the x-axis direction is the lower limit coordinate x. min =0.29, the average edge length is 0.2, and the boundary element structure corresponds to the floor(0.29 / 0.2)=1 in the x-axis direction of the virtual box, denoted as (I1, J, K). J and K are variable, and the cycle of J and K corresponds to the lower back side of a face. The calculation of J and K is the same as the method of calculating the number J and K in S50 using the center coordinate values ​​of the y and z directions (i.e. the first coordinate values ​​of the y and z axes at this time), which will not be repeated here. Other boundary element structures in the same column as this boundary element structure are located on the upper boundary.

[0078] S50 has mapped all tetrahedral structures, including boundary element structures, to corresponding virtual boxes. It then determines whether the calculated numbers (I, J1, K) or (I1, J, K) have corresponding virtual boxes. If they do, it searches for the adjacent boundary element structure corresponding to that number (I, J1, K) or (I1, J, K) within the virtual boxes. Specifically:

[0079] Obtain the corresponding second coordinate value based on the first coordinate value:

[0080] For the left and right boundaries, the second coordinate value includes the lower or upper y-axis coordinate of the boundary unit structure in the same row as the first boundary unit structure. That is, if the first coordinate value of a boundary unit structure includes the upper y-axis coordinate, then the second coordinate value includes the lower y-axis coordinate of the boundary unit structure in the same row as the first boundary unit structure; conversely, if the first coordinate value of a boundary unit structure includes the lower y-axis coordinate, then the second coordinate value includes the upper y-axis coordinate of the boundary unit structure in the same row as the first boundary unit structure. For example, the first coordinate value includes the lower y-axis coordinate... min The second coordinate value includes the upper limit coordinate of the y-axis. max The first coordinate value includes the upper limit coordinate of the y-axis. max The second coordinate value includes the lower limit coordinate of the y-axis. min .

[0081] Similarly, for the upper and lower boundaries, the first coordinate value includes the lower or upper x-axis coordinate of the boundary unit structure in the same column as the current boundary unit structure. That is, if the first coordinate value of a boundary unit structure includes the upper x-axis coordinate, then the second coordinate value includes the lower x-axis coordinate of the boundary unit structure in the same column as the current boundary unit structure. Conversely, if the first coordinate value of a boundary unit structure includes the lower x-axis coordinate, then the second coordinate value includes the upper x-axis coordinate of the boundary unit structure in the same row as the current boundary unit structure. For example, the first coordinate value includes the lower x-axis coordinate... min The second coordinate value includes the upper limit coordinate of the x-axis. max The first coordinate value includes the upper limit coordinate of the x-axis. max The second coordinate value includes the lower limit coordinate of the x-axis. min .

[0082] Furthermore, the number of the boundary unit structure in the virtual box that is in the same row or column is calculated based on the second coordinate value and the average edge length. The calculation method is the same as the method described above for calculating the number of the boundary unit structure in the virtual box, which can be expressed as floor(second coordinate value / average edge length). This can be used to determine the number of other boundary unit structures in the virtual box that are in the same row or column as the boundary unit structure, which are denoted as (I, J2, K) and (I2, J, K) respectively.

[0083] As shown in S50, for any boundary element structure, the corresponding virtual box is mapped based on its center coordinates, and a unique number can be assigned to each boundary element structure based on these center coordinates. Conversely, using the known number and its corresponding center coordinates, the corresponding adjacent boundary element structure to be searched can be deduced. That is, floor(center coordinates / average edge length) can be used to calculate the number of the virtual box, and the corresponding center coordinates can be calculated using the number of the virtual box and the average edge length.

[0084] For example, the center coordinates corresponding to the number (I, J2, K) can be deduced. Since the divided virtual boxes form a cube structure, the I and K coordinates of the boundary unit structures in the same row remain consistent with those in the number (I, J1, K). Similarly, the center coordinates corresponding to the number (I2, J, K) can be deduced, and the J and K coordinates of the boundary unit structures in the same column remain consistent with those in the number (I1, J, K). Different center coordinates correspond to different boundary unit structures, and the corresponding adjacent boundary unit structures can be found based on the center coordinates.

[0085] Furthermore, in order to obtain a more accurate boundary element structure, the corresponding method in this embodiment of the invention further includes:

[0086] The adjacent boundary unit structures are determined based on the adjacent boundary unit structures. For example, if the adjacent boundary unit structure (I, J2, K) is determined in S60, then (I-1, J2, K), (I+1, J2, K), (I, J2, K-1), and (I, J2, K+1) are positive and negative corrections on I and K of (I, J2, K), which determine the numbers of the four adjacent virtual boxes. The other boundary unit structures adjacent to this adjacent boundary unit structure can be obtained by reverse deduction from the numbers of the virtual boxes input in S50.

[0087] Furthermore, the corresponding method in this embodiment of the invention also includes:

[0088] The polygonal overlapping region is calculated based on the adjacent boundary unit structures and other boundary unit structures adjacent to it. This polygonal overlapping region is used in numerical electromagnetic field algorithms to calculate the periodic structure of the electromagnetic field. Here, a polygon clipping algorithm can be used to calculate the information of the polygonal overlapping region; the polygon can be quadrilateral, pentagonal, hexagonal, etc. For example... Figure 4 As shown, the boundary element structures on the left and right are respectively Figure 3 The boundary unit structures e1 and e2 in the model are polygonal overlapping regions formed by the boundary unit structures e1 and e2.

[0089] It should be noted that the method proposed in this embodiment of the invention is also applicable to conformal electromagnetic field periodic structure mesh models. Here, the emphasis is on its ability to solve the problem that the structure of adjacent boundary elements in non-conformal electromagnetic field periodic structure mesh models cannot be quickly determined in current methods.

[0090] To verify the effectiveness of the fast determination method for adjacent boundary elements of the periodic structure mesh model proposed in this embodiment of the invention, the following experiments are conducted.

[0091] The embodiments of the present invention provide different numbers of tetrahedral structures in a periodic electromagnetic field structure mesh model. Experiments were conducted using the method of the present invention and the existing exhaustive method, and the comparison results of the calculation time in the process of judging adjacent boundary elements are shown in Table 1.

[0092] Table 1 Comparison Results of Calculation Time

[0093] Number of tetrahedrons 37457 60405 92514 142871 This invention 0.4 seconds 0.8 seconds 1.3 seconds 2.4 seconds Exhaustive search 1.6 minutes 2.6 minutes 5.9 minutes 13.1 minutes

[0094] From Table 1, and Figure 5 (a)~ Figure 5 (b) It can be seen that the computational efficiency of the method of the present invention increases linearly with different numbers of tetrahedrons, and the effect is very good. However, when using the exhaustive method, the computation time is 1.6 minutes when the number of tetrahedrons is 37457, which is about two hundred times that of the method of the present invention. When the number of tetrahedrons is 142871, the computation time is 13 minutes, which is about three hundred times that of the method of the present invention. The difference is huge, and this difference will widen further when the number of tetrahedrons increases.

[0095] Clearly, the present invention utilizes a spatial box-projection method, which has low programming difficulty and good computational efficiency.

[0096] In summary, the fast boundary element determination method for periodic structure mesh models proposed in this invention provides a novel approach to spatial box mapping: The spatial region formed by all tetrahedral structures in the electromagnetic field periodic structure mesh model is divided into several virtual boxes. All virtual boxes constitute a cubic mesh structure. Boundary element structures are determined from all tetrahedral structures, and the center coordinates of each boundary element structure are calculated. Based on the center coordinates, all boundary element structures are mapped to the corresponding numbered virtual boxes. Subsequently, for any boundary element structure, it is only necessary to first calculate the number of the boundary element and the corresponding virtual box, and then search for the adjacent boundary element structure corresponding to that number within the virtual boxes. Therefore, the spatial box mapping method proposed in this invention, for electromagnetic field periodic structure mesh models with non-conformal left and right boundaries and / or top and bottom boundaries, significantly reduces the search depth and improves computational efficiency compared to existing exhaustive methods.

[0097] Secondly, please see Figure 6 This invention proposes a method for rapid determination of adjacent boundary elements in a periodic structure mesh model. This method is applied to electromagnetic field periodic structure mesh models where the left and right boundaries and / or the top and bottom boundaries are non-conformal. The electromagnetic field periodic structure mesh model includes several tetrahedral structures, and the corresponding device includes:

[0098] The first calculation unit 601 is used to calculate the average edge length based on all tetrahedral structures;

[0099] Dividing unit 602 is used to divide the spatial region formed by all tetrahedral structures in the electromagnetic field periodic structure grid model into several virtual boxes with the average edge length as the dividing interval.

[0100] The first determining unit 603 is used to determine the boundary unit structure based on the coordinate values ​​of the four vertices constituting the tetrahedral structure in each tetrahedral structure.

[0101] The second calculation unit 604 is used to calculate the center coordinates of each boundary unit structure;

[0102] Mapping unit 605 is used to map each boundary unit structure to a corresponding virtual box according to the center coordinates; wherein each virtual box corresponds to a number;

[0103] The lookup unit 606 is used to calculate the number of each boundary unit structure in the virtual box for each boundary unit structure, determine whether there is a virtual box corresponding to the number, and if so, search for the adjacent boundary unit structure corresponding to the number in the virtual box.

[0104] Furthermore, in this embodiment of the invention, the second calculation unit 604 calculates the center coordinates of each boundary unit structure, including:

[0105] Calculate the coordinates of the four vertices of each boundary unit structure in a three-dimensional orthogonal Cartesian coordinate system;

[0106] The average of the coordinates of the four vertices is used as the center coordinates of the corresponding boundary unit structure.

[0107] Furthermore, in this embodiment of the invention, the mapping unit 605 maps each boundary unit structure to a corresponding virtual box based on its center coordinates, including:

[0108] Calculate the virtual box number of each boundary unit structure based on the center coordinates and average edge length, and map each boundary unit structure to the virtual box with the corresponding number.

[0109] Further, in this embodiment of the invention, the search unit 606 calculates the number of the boundary unit structure in the virtual box, including:

[0110] Obtain the first coordinate value corresponding to the boundary element structure in the electromagnetic field periodic structure mesh model; wherein, for the left and right boundaries, the first coordinate value includes the upper or lower y-axis coordinate of the boundary element structure, and for the upper and lower boundaries, the first coordinate value includes the upper or lower x-axis coordinate of the boundary element structure.

[0111] The number of the boundary element structure in the virtual box is calculated based on the first coordinate value and the average edge length.

[0112] Further, in this embodiment of the invention, the search unit 606 searches for the adjacent boundary unit structure corresponding to the number in the virtual box, including:

[0113] The corresponding second coordinate value is obtained based on the first coordinate value; wherein, for the left and right boundaries, the second coordinate value is the lower or upper y-axis coordinate of the boundary unit structure in the same row as the boundary unit structure; for the upper and lower boundaries, the first coordinate value includes the lower or upper x-axis coordinate of the boundary unit structure in the same column as the boundary unit structure.

[0114] Calculate the number of the boundary unit structures in the virtual box that are in the same row or column based on the second coordinate value and the average edge length;

[0115] The center coordinates of the boundary unit structures in the same row or column in the virtual box are calculated based on their numbers and the average edge length. The corresponding adjacent boundary unit structures are then located based on these center coordinates.

[0116] Further, please see Figure 7 Another device for fast determination of adjacent boundary elements in a periodic structure mesh model proposed in this embodiment of the invention further includes:

[0117] The second determining unit 607 is used to determine other boundary unit structures adjacent to the adjacent boundary unit structure based on the adjacent boundary unit structure.

[0118] Further, please see Figure 8 Another device for quickly determining adjacent boundary elements in a periodic structure mesh model proposed in this embodiment of the invention further includes:

[0119] The third calculation unit 608 is used to calculate the polygonal overlapping region based on the adjacent boundary unit structure and other boundary unit structures adjacent to the adjacent boundary structure. The polygonal overlapping region is used by the electromagnetic field numerical algorithm to calculate the periodic structure of the electromagnetic field.

[0120] Thirdly, please see Figure 9This invention provides an electronic device, including a processor 801, a communication interface 802, a memory 803, and a communication bus 804, wherein the processor 801, the communication interface 802, and the memory 803 communicate with each other through the communication bus 804.

[0121] Memory 803 is used to store computer programs;

[0122] When the processor 801 executes the program stored in the memory 803, it implements the steps of the above-mentioned method for quickly determining adjacent boundary elements of the periodic structure mesh model.

[0123] Fourthly, embodiments of the present invention provide a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the steps of the above-described method for quickly determining adjacent boundary elements of a periodic structure mesh model.

[0124] For the embodiments of the device / electronic device / storage medium, since they are basically similar to the method embodiments, the description is relatively simple, and relevant parts can be referred to in the description of the method embodiments.

[0125] In the description of this invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0126] Although the invention has been described herein in conjunction with various embodiments, those skilled in the art, by reviewing the specification and accompanying drawings, will understand and implement other variations of the disclosed embodiments in carrying out the claimed invention. In the specification, the word "comprising" does not exclude other components or steps, and "a" or "an" does not exclude a plurality. While certain measures are described in different embodiments, this does not mean that these measures cannot be combined to produce good results.

[0127] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the scope of protection of the present invention.

Claims

1. A method for fast determination of adjacent boundary elements in a periodic structure mesh model, characterized in that, The electromagnetic field periodic structure mesh model is applied to phased array antennas with non-conformal left and right boundaries and / or top and bottom boundaries. The electromagnetic field periodic structure mesh model includes several tetrahedral structures, and the corresponding methods include: Calculate the average edge length based on all tetrahedral structures; Using the average edge length as the dividing interval, the spatial region formed by all tetrahedral structures in the electromagnetic field periodic structure grid model is divided to obtain several virtual boxes. The boundary element structure is determined based on the coordinate values ​​of the four vertices that constitute the tetrahedral structure. Calculate the center coordinates of each boundary element structure; Each boundary unit structure is mapped to a corresponding virtual box based on the center coordinates; wherein each virtual box corresponds to a number; For each boundary element structure, calculate the number of the boundary element structure in the virtual box, determine whether there is a virtual box corresponding to the number, and if there is, search for the adjacent boundary element structure corresponding to the number in the virtual box. The calculation of the boundary element structure's number in the virtual box includes: obtaining the first coordinate value corresponding to the boundary element structure in the electromagnetic field periodic structure mesh model; wherein, for the left and right boundaries, the first coordinate value includes the upper or lower y-axis coordinate of the boundary element structure, and for the upper and lower boundaries, the first coordinate value includes the upper or lower x-axis coordinate of the boundary element structure; and calculating the number of the boundary element structure in the virtual box based on the first coordinate value and the average edge length. The process of finding the adjacent boundary unit structure corresponding to the given number in the virtual box includes: obtaining the corresponding second coordinate value based on the first coordinate value; wherein, for the left and right boundaries, the second coordinate value includes the lower or upper y-axis coordinate of the boundary unit structure in the same row as the given boundary unit structure, and for the upper and lower boundaries, the first coordinate value includes the lower or upper x-axis coordinate of the boundary unit structure in the same column as the given boundary unit structure; calculating the number of the boundary unit structure in the same row or column in the virtual box based on the second coordinate value and the average edge length; calculating the corresponding center coordinate based on the number of the boundary unit structure in the same row or column in the virtual box and the average edge length, and finding the corresponding adjacent boundary unit structure based on the center coordinate.

2. The method for fast determination of adjacent boundary elements in a periodic structure mesh model according to claim 1, characterized in that, Calculate the center coordinates of each boundary element structure, including: Calculate the coordinates of the four vertices of each boundary unit structure in a three-dimensional orthogonal Cartesian coordinate system; The average of the coordinates of the four vertices is used as the center coordinates of the corresponding boundary unit structure.

3. The method for fast determination of adjacent boundary elements in a periodic structure mesh model according to claim 1, characterized in that, Mapping each boundary unit structure to its corresponding virtual box based on the center coordinates includes: Calculate the number of each boundary unit structure mapped to the virtual box based on the center coordinates and the average edge length, and map each boundary unit structure to the virtual box with the corresponding number.

4. The method for fast determination of adjacent boundary elements in a periodic structure mesh model according to claim 1, characterized in that, Corresponding methods also include: Based on the adjacent boundary unit structure, other boundary unit structures adjacent to the adjacent boundary unit structure are determined.

5. The method for fast determination of adjacent boundary elements in a periodic structure mesh model according to claim 4, characterized in that, Corresponding methods also include: Based on the adjacent boundary unit structure and other boundary unit structures adjacent to the adjacent boundary unit structure, the polygonal overlapping region is calculated. The polygonal overlapping region is used by the electromagnetic field numerical algorithm to calculate the periodic structure of the electromagnetic field.

6. A device for rapidly determining adjacent boundary elements in a periodic mesh model, characterized in that, The electromagnetic field periodic structure mesh model is applied to a phased array antenna with non-conformal left and right boundaries and / or top and bottom boundaries. The electromagnetic field periodic structure mesh model includes several tetrahedral structures. The device includes: The first calculation unit is used to calculate the average edge length based on all tetrahedral structures; The partitioning unit is used to divide the spatial region formed by all tetrahedral structures in the electromagnetic field periodic structure grid model into several virtual boxes, with the average edge length as the partitioning interval. The first determining unit is used to determine the boundary unit structure based on the coordinate values ​​of the four vertices constituting the tetrahedral structure in each tetrahedral structure. The second calculation unit is used to calculate the center coordinates of each boundary unit structure; A mapping unit is used to map each boundary unit structure to a corresponding virtual box according to the center coordinates; wherein each virtual box corresponds to a number; A lookup unit is used to calculate the number of each boundary element structure in a virtual box for each boundary element structure, determine whether a virtual box corresponding to that number exists, and if so, search for the adjacent boundary element structure corresponding to that number in the virtual box. Calculating the number of the boundary element structure in the virtual box includes: obtaining the first coordinate value corresponding to the boundary element structure in the electromagnetic field periodic structure mesh model; wherein, for left and right boundaries, the first coordinate value includes the upper or lower y-axis coordinate of the boundary element structure, and for upper and lower boundaries, the first coordinate value includes the upper or lower x-axis coordinate of the boundary element structure; calculating the number of the boundary element structure in the virtual box based on the first coordinate value and the average edge length; wherein, in the virtual box... The process of finding the adjacent boundary unit structure corresponding to the given number in the virtual box includes: obtaining the corresponding second coordinate value based on the first coordinate value; wherein, for the left and right boundaries, the second coordinate value includes the lower or upper y-axis coordinate of the boundary unit structure in the same row as the given boundary unit structure; for the upper and lower boundaries, the first coordinate value includes the lower or upper x-axis coordinate of the boundary unit structure in the same column as the given boundary unit structure; calculating the number of the boundary unit structure in the same row or column in the virtual box based on the second coordinate value and the average edge length; calculating the corresponding center coordinate based on the number of the boundary unit structure in the same row or column in the virtual box and the average edge length; and finding the corresponding adjacent boundary unit structure based on the center coordinate.

7. The device for rapid determination of adjacent boundary elements in a periodic structure mesh model according to claim 6, characterized in that, The corresponding device also includes: The second determining unit is used to determine other boundary unit structures adjacent to the adjacent boundary unit structure based on the adjacent boundary unit structure.

8. The device for rapid determination of adjacent boundary elements in a periodic structure mesh model according to claim 7, characterized in that, The corresponding device also includes: The third calculation unit is used to calculate the polygonal overlapping region based on the adjacent boundary unit structure and other boundary unit structures adjacent to the adjacent boundary unit structure. The polygonal overlapping region is used by the electromagnetic field numerical algorithm to calculate the periodic structure of the electromagnetic field.

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