Satellite-borne phased array low-grating lobe antenna array plane

Abstract

The invention discloses a satellite-borne phased array low-grating lobe antenna array plane, which is characterized in that a plurality of units are arranged on the array plane, an inner ring and an outer ring are sequentially arranged from the center to the outer side of the array plane, the units on the inner ring are arranged to be a plurality of concentrated structures, the units on the outer ring form a plurality of non-uniform discrete structures, and the units are gradually sparsely arranged from the inner ring to the outer ring. And the periodicity of the array plane is destroyed. The antenna array plane ensures that the antenna core gain is not lost through the inner ring concentration structure, and provides basic performance support for communication / detection; the combination of the outer ring non-uniform discrete structure and the sparse arrangement fundamentally destroys the periodicity of the array plane, scatters grating lobe energy into weak dispersion signals, and achieves powerful grating lobe suppression. Meanwhile, the number of antenna units, matched T / R assemblies and radio frequency channels is greatly reduced through sparse arrangement, the array surface weight and the system cost are remarkably reduced, sufficient space is reserved for heat dissipation, and finally the optimal balance among wide-angle scanning, anti-interference performance and satellite-borne engineering practicability is achieved.

Description

TECHNICAL FIELD

[0001] The application relates to the field of antenna arrays, in particular to a low-grating-lobe antenna array of a satellite-borne phased array. BACKGROUND

[0002] With the development of antenna technology and satellite communication, the requirements for communication rate and accuracy are gradually increasing, and it is required to fundamentally balance between wider scanning angle, lower sidelobe, higher aperture efficiency, and lower system complexity and cost. More and more satellite technology solutions adopt the form of phased arrays. The traditional phased array antenna layout adopts a uniform full distribution form, and while pursuing high density and high performance, the number of antenna channels is large, and the T / R components responsible for excitation scanning in the rear end also increase. The power is small and the heat dissipation is difficult, which causes various problems, and faces multiple bottlenecks of mutual coupling, grating lobes, and large weight, high cost, and high complexity. Even if the gain and directivity requirements are met, there are still many performance and engineering problems.

[0003] At present, the most common phased array antenna adopts a full-distributed dense layout, that is, the antenna units are periodically and uniformly arranged on a rectangular or triangular grid. In order to ensure that no grating lobes appear during scanning, the unit spacing is usually limited to less than one-half of the operating wavelength. Although this layout is simple in design and has high gain, it has the following inherent defects. On the one hand, the periodic arrangement causes serious mutual coupling between the units, causing high sidelobes. On the other hand, the large array size and the large number of unit channels cause the number and cost of radio frequency channels, digital processing links, power supplies, and cooling systems to increase exponentially. SUMMARY

[0004] The purpose of the present application is to provide a satellite-borne phased array low-grating-lobe antenna array, which balances between wide-angle scanning, anti-interference performance, and satellite-borne engineering practicability through the combination of inner circle concentration structure, outer circle non-uniform discrete structure, and sparse arrangement. The specific technical solutions are as follows: A satellite-borne phased array low-grating-lobe antenna array, a plurality of units are arranged on the array, and an inner circle and an outer circle are arranged from the center of the array to the outer side in sequence. The units on the inner circle are arranged as a plurality of concentration structures, and the units on the outer circle form a plurality of non-uniform discrete structures. The units are gradually arranged sparsely from the inner circle to the outer circle to destroy the periodicity of the array.

[0005] Further, the inner circle includes a first inner array part and a second inner array part arranged outside the first inner array part, and the outer circle includes a first outer array part arranged outside the second inner array part and a second outer array part arranged outside the first outer array part.

[0006] Further, the number of unit rows on the first inner array part is greater than the number of unit rows on the second inner array part, the number of unit rows on the second inner array part is equal to the number of unit rows on the first outer array part, and the number of unit rows on the first outer array part is greater than the number of unit rows on the second outer array part.

[0007] Furthermore, with the center of the array as the intersection point, four quadrants are formed in sequence, and the units in two adjacent quadrants are arranged symmetrically.

[0008] Furthermore, the quadrant includes a first subarray and a second subarray arranged opposite to each other, and the second inner array forms a trapezoidal structure on the first subarray and the second subarray, respectively.

[0009] Furthermore, the first inner array forms a triangular structure in the quadrant so that the first inner array has a square structure.

[0010] Furthermore, the first inner array also includes a raised strip, which is located on the side of the first inner array near the second inner array.

[0011] Furthermore, the first outer array and the second outer array are distributed along multiple angular directions in the quadrant, and the angular directions are evenly spaced radially along the quadrant. The number of cell rows on the first outer array is set to four, and the number of cell rows on the second outer array is set to two. The cells in each angular direction are non-uniformly arranged in the row direction and form non-uniform empty columns.

[0012] Furthermore, the array surface is configured with a smooth contour structure.

[0013] Furthermore, the center-to-center distance between two adjacent cells is greater than half the wavelength of the required grating lobe suppression condition.

[0014] The spaceborne phased array low-grating-lobe antenna array of the present invention has the following advantages: 1. The concentrated structure in the inner ring ensures that the antenna core gain is not lost, providing basic performance support for communication / detection; the combination of the non-uniform discrete structure and sparse arrangement in the outer ring fundamentally destroys the periodicity of the array, dispersing the grating lobe energy into weak and dispersed signals, achieving strong grating lobe suppression; at the same time, the sparse arrangement significantly reduces the number of antenna elements and supporting T / R components and RF channels, significantly reducing the array weight and system cost, and also reserving sufficient space for heat dissipation, ultimately achieving the optimal balance between wide-angle scanning, anti-interference performance and practicality for spaceborne engineering.

[0015] 2. The first inner array section, serving as the core radiation area, provides the antenna's basic gain and directivity through dense arrangement. The second inner array section serves as the density transition between the inner and outer rings, effectively avoiding high sidelobes caused by abrupt changes in element distribution. The first and second outer array sections gradually enhance the non-uniform and sparse arrangement from the inside out, layer by layer dismantling the periodicity of the uniform layout and continuously weakening the influence of grating lobes. This layered structure allows for precise functional adaptation of each region, ensuring both the stability of core performance and greater flexibility in array layout control.

[0016] 3. The first inner array ensures dense arrangement of elements with the most rows, thus solidifying the core radiation gain of the antenna; the second inner array has fewer rows than the first inner array, but the same number of rows as the first outer array, which achieves a smooth density transition between the inner and outer rings, avoids high sidelobes caused by energy mutations, and does not form a new uniform period; the first outer array has more rows than the second outer array, further enhancing the sparsity effect of the outer ring and deeply disrupting the periodicity.

[0017] 4. The four-quadrant and adjacent-quadrant symmetrical layout formed by orthogonal segmentation ensures that the radiation characteristics of the antenna are uniform in all directions, and key indicators such as beamwidth and gain remain stable throughout the full scanning range, avoiding signal distortion caused by layout asymmetry. At the same time, the symmetrical structure can complement the sparse arrangement with dense inner and sparse outer layers, breaking the strong periodicity of the traditional uniform layout while maintaining the overall structural regularity, helping to disperse grating lobe energy and improve anti-interference capability.

[0018] 5. By dividing the quadrant into relative subarrays through oblique segmentation, and in conjunction with the density gradient characteristics of the trapezoidal structure, a smooth connection between the inner core area and the outer transition area is achieved, effectively avoiding high sidelobes caused by abrupt changes in element distribution. The combination of oblique array form and trapezoidal irregular shape doubly breaks down the periodicity of traditional uniform grids, further dispersing grating lobe energy and improving grating lobe suppression effect. The short side of the trapezoid supports the dense arrangement of the first inner array, ensuring the continuity of gain connection, while the long side adapts to the layout expansion requirements of the first outer array. Moreover, the symmetrical subarrays and trapezoidal structure maintain the consistency of radiation characteristics in all directions, improving the stability of wide-angle scanning of the antenna.

[0019] 6. By forming isosceles right-angled triangle structures in each quadrant through the first inner array, the overall structure becomes a square after splicing. This ensures the high symmetry of the unit arrangement, making the radiation characteristics uniform in all directions and the beamwidth consistent. At the same time, the dense arrangement in the square area provides a foundation for the antenna core gain, compensating for the gain loss that may be caused by the sparsity of the outer ring. The triangular structure is precisely adapted to the four-quadrant segmentation layout, making the inner ring structure and the overall array surface more seamlessly connected. Meanwhile, the regular shape of the square contrasts with the non-uniform discrete layout of the subsequent outer ring, further disrupting the overall periodicity of the array surface and enhancing the grating lobe suppression effect while ensuring core performance. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the layout of the spaceborne phased array low-grating lobe antenna of the present invention. Figure 1 .

[0021] Figure 2 This is a schematic diagram showing the quadrant division of the spaceborne phased array low-grid lobe antenna array of the present invention.

[0022] Figure 3 This is a schematic diagram showing the division of the spaceborne phased array low-grid lobe antenna array according to the circular aperture of the present invention.

[0023] Figure 4 This is a schematic diagram of the layout structure of the second inner array section in the low-grid lobe antenna array of the spaceborne phased array of the present invention.

[0024] Figure 5 This is a schematic diagram of the layout structure of the first outer array section in the spaceborne phased array low grating lobe antenna array of the present invention.

[0025] Figure 6 This is a schematic diagram of the layout structure of the second outer array section in the low-grid lobe antenna array of the spaceborne phased array of the present invention.

[0026] Figure 7 This is a schematic diagram of the layout of the spaceborne phased array low-grating lobe antenna of the present invention. Figure 2 .

[0027] Figure 8 This is a high-frequency simulation radiation pattern of the low-grid lobe antenna array layout of the spaceborne phased array of the present invention when phi=0°.

[0028] Figure 9 This is a high-frequency simulation radiation pattern of the low-grid lobe antenna array layout of the spaceborne phased array of the present invention when phi=45°.

[0029] Figure 10 This is a schematic diagram of a rectangular layout for a phased array antenna.

[0030] Figure 11 This is a high-frequency simulation pattern of a phased array antenna with phi=0° in a rectangular layout, serving as a comparative example.

[0031] Figure 12 This is a schematic diagram of the layout of a full-scale dual phased array antenna rotating around the center.

[0032] Figure 13 The high-frequency simulation pattern of a full-scale dual phased array antenna with phi=0° is shown.

[0033] Figure 14 This is a schematic diagram of the layout of a full-scale three-phase array antenna rotating around the center.

[0034] Figure 15 The high-frequency simulation pattern is shown for the second type of rotating layout around the center of the proportional three-phase array antenna when phi=0°. Detailed Implementation

[0035] To better understand the purpose, structure, and function of this invention, the spaceborne phased array low-grid-lobe antenna array of this invention will be described in detail below with reference to the accompanying drawings.

[0036] like Figures 1 to 7As shown, the present invention discloses a spaceborne phased array low grating lobe antenna array, taking a digital DBF phased array antenna as an example. The array is configured as a circular structure, with an inner ring 20 and an outer ring 21 arranged sequentially from the center of the array outward. The elements on the inner ring 20 are configured as multiple concentrated structures, which means that multiple elements are densely and regularly arranged to ensure the core gain requirements of the antenna. The elements on the outer ring 21 form multiple non-uniform discrete structures, which means that multiple elements are not arranged according to a fixed grating pattern but are dispersed, thereby avoiding the formation of periodic signal superposition. As a result, the elements gradually become sparser from the inner ring 20 to the outer ring 21, that is, from the inner ring 20 to the outer ring 21, the distribution density of the elements gradually decreases, further disintegrating the periodic structure of the array.

[0037] The purpose of the above structure is to effectively suppress grating lobes by breaking the periodicity of the uniform layout, while balancing gain and engineering practicality. The circular structure avoids high sidelobes caused by sudden truncation at the layout edge, the concentrated structure in the inner ring 20 ensures the basic gain, and the combination of non-uniform discrete and sparse arrangement in the outer ring 21 breaks the periodicity of the array surface, dispersing the grating lobe energy into weak dispersed signals. This reduces the number of antenna channels and T / R components to reduce weight and cost, while improving the grating lobe suppression capability and anti-interference performance, achieving a balance between performance and engineering requirements.

[0038] Understandably, the array can also be set as a rounded, chamfered polygon, or elliptical or other smooth contour structure, as long as it is symmetrical in all directions, maintains a consistent radiation pattern and beamwidth, reduces sudden cutoffs at both ends of the linear array, and prevents high sidelobes caused by drastic amplitude jumps.

[0039] It should be noted that the distance between the centers of two adjacent units is three times the wavelength of the required high-frequency band, which increases the electromagnetic isolation distance between units, weakens the mutual coupling effect from a physical perspective, and leaves more physical gaps between units, thus avoiding the heat dissipation congestion problem caused by the close arrangement of units in traditional dense layouts.

[0040] It is understandable that those skilled in the art can set the center-to-center distance between two adjacent units to be greater than half the wavelength of the required gate lobe suppression condition, as long as it can achieve the technical effect of reducing mutual coupling effect and avoiding heat dissipation congestion.

[0041] Preferred, such as Figure 3As shown, the inner ring 20 includes a circular first inner array 22 and an annular second inner array 23 located outside the first inner array 22. The first inner array 22 serves as the core area, with dense arrangement to ensure the antenna's basic gain and directivity. The second inner array 23 connects the core and the outer ring 21, serving as a density transition to avoid abrupt energy changes. The outer ring 21 includes an annular first outer array 24 located outside the second inner array 23 and an annular second outer array 25 located outside the first outer array 24. The first outer array 24 and the second outer array 25 are arranged in a non-uniform and sparse manner from the inside to the outside, breaking the periodicity of the uniform array layout layer by layer, and dispersing the grating lobe energy into weak and dispersed signals. This constructs a structure that ensures core gain and disrupts gradient periodicity, achieving grating lobe suppression and performance balance.

[0042] Furthermore, the number of element rows on the first inner array 22 is greater than the number of element rows on the second inner array 23. The first inner array 22, as the antenna radiation core, has the most rows to ensure dense element arrangement and solidify the basic gain. The number of element rows on the second inner array 23 is equal to the number of element rows on the first outer array 24. The number of rows on the second inner array 23 is less than that on the first inner array 22, serving as a density transition to avoid high sidelobes caused by sudden energy changes between the inner ring 20 and the outer ring 21. It also has the same number of rows as the first outer array 24, ensuring the stability of the array connection while avoiding the formation of a uniform period. The number of rows of elements on the first outer array 24 is greater than the number of rows of elements on the second outer array 25, and the number of rows on the first outer array 24 is greater than the number on the second outer array 25. This causes the number of rows on the outer ring 21 to gradually decrease. Combined with non-uniform discrete and sparse arrangement, this further breaks down the periodic structure and disperses the grating lobe energy into a weak, dispersed signal. At the same time, the total number of elements in each array is reasonably controlled, and the number of antenna channels and T / R components is reduced to achieve weight reduction and cost reduction, and to reserve space for heat dissipation. Thus, through the gradient allocation of the number of rows, the dual requirements of ensuring the gain of the inner ring 20 and the periodic disruption of the outer ring 21 are met, achieving a balance between performance and engineering indicators.

[0043] Furthermore, such as Figure 2 As shown, with the center of the array as the intersection point, four quadrants are formed sequentially by orthogonal dividing lines: Quadrant 1 (26), Quadrant 27, Quadrant 3 (28), and Quadrant 4 (29). The elements in adjacent quadrants are symmetrically arranged with the orthogonal dividing lines as the axis. This ensures the uniformity of the antenna's radiation characteristics in all directions, keeping beamwidth, gain, and other indicators consistent across the entire scanning range, and avoiding signal distortion caused by asymmetrical layout. It also complements the circular boundary and the sparse arrangement with denser inner layers and sparser outer layers. While maintaining the overall symmetrical structure, it does not form a uniform periodic grid. Instead, the symmetrical complementarity between quadrants further breaks down the periodicity of the traditional uniform layout, helping to disperse grating lobe energy. This achieves a synergistic effect of pattern stability and periodic disruption, balancing performance consistency and grating lobe suppression.

[0044] Preferably, the first inner array 22 forms an isosceles right-angled triangle structure in the quadrant, making the first inner array 22 a square structure. This ensures the symmetry of the element arrangement, making the radiation characteristics uniform in all directions and the beamwidth consistent, while also ensuring the core gain of the antenna through the dense arrangement in the square area. The first inner array 22 also includes a long strip-shaped protrusion located on the side of the first inner array 22 near the second inner array 23, fitting snugly at the center of the hypotenuse of the isosceles right-angled triangle. On the one hand, this achieves a smooth transition between the inner rings 20, avoiding high sidelobes caused by density abrupt changes. On the other hand, it breaks the single regularity of the square structure, further disrupting the simple periodic layout. Combined with the overall sparseness and non-uniform arrangement, it helps suppress grating lobes without reducing gain. Moreover, the symmetrical and simple structure is suitable for the assembly process of spaceborne antennas. Thus, this structure achieves a balance between the core gain of the inner ring 20 and the stability of the array connection, while also helping to enhance the technical effect of grating lobe suppression by disrupting periodicity.

[0045] It is understandable that those skilled in the art can increase the number of rows of convex strips according to the actual situation, forming a cone shape with the tip facing the direction of the second inner array 23, as long as it can achieve the effect of avoiding high sidelobe caused by density abrupt change.

[0046] Furthermore, using the center of the array as the intersection point, the quadrant is divided into a first subarray 30 and a second subarray 31, arranged opposite each other along the diagonal dividing line at a 45° angle. The second inner array 23 forms trapezoidal structures on the first subarray 30 and the second subarray 31, respectively. The short side of the trapezoidal structure is located closer to the first inner array 22, and the long side of the trapezoidal structure is located closer to the first outer array 24. This achieves a smooth increase in density between the core region of the inner circle 20 and the transition region of the outer circle 21, avoiding high sidelobes caused by abrupt changes in unit distribution, and also achieves a smooth increase in density through the non-... The regular shape breaks the periodicity of the traditional uniform grid. Combined with the obliquely divided first subarray 30 and second subarray 31, it further breaks the periodicity of signal superposition, causing the grid lobe energy to be dispersed into weak and scattered signals. At the same time, the trapezoidal short side supports the dense arrangement of the first inner array 22 to ensure gain connection, while the long side adapts to the layout expansion requirements of the first outer array 24. The symmetrical trapezoidal structure maintains the consistency of radiation characteristics in all directions. In addition, the oblique array and trapezoidal gradient layout strengthen the periodic disruption and array connection, and improve the grid lobe suppression and gain stability.

[0047] Furthermore, the first outer array 24 and the second outer array 25 are distributed along multiple angular directions in the quadrant, and the angular directions are evenly spaced along the radial direction of the quadrant to maintain the consistency of the radiation characteristics of the antenna in each direction and avoid the regular periodicity formed by a single angular arrangement.

[0048] The circumferential direction of the circular array is defined as the row of elements, and the radial direction of the array is defined as the column of elements. Therefore, the number of element rows on the first outer array 24 is set to four, and the number of element rows on the second outer array 25 is set to two. This adapts to the sparsity requirement from the inner ring 20 to the outer ring 21, ensuring a smooth decrease in element density and avoiding high sidelobes caused by sudden energy changes. The elements in each angular direction are non-uniformly arranged in the row direction, forming non-uniform empty columns. This completely disperses the grating lobe energy into a weak, dispersed signal, deeply disrupting the array's periodicity to enhance grating lobe suppression, while simultaneously ensuring radial symmetry and engineering adaptability.

[0049] It should be noted that non-uniform arrangement in the row direction refers to the fact that the distribution of units in each angular direction does not follow a fixed spacing or fixed number rule in the circumferential direction. That is, the units in the same column do not occupy the preset positions in that row direction evenly, the row spacing between units is inconsistent, there is no uniform rule for whether units are set in each row, some rows have units and some rows do not have units, and the spacing between rows with units is not equal, breaking the periodicity of each row and column arranged at a fixed spacing in the traditional uniform layout. Non-uniform empty columns refer to "empty columns" without any units in each angular direction distributed radially, which are not distributed at fixed intervals. That is, the appearance of empty columns is irregular. It is neither that an empty column appears every fixed number of columns, nor that a fixed number of empty columns appear in a specific area. The interval between empty columns and non-empty columns (columns with units) is random or adjusted as needed to avoid forming a regular column-oriented periodic structure. This, combined with non-uniform arrangement, undermines the overall periodicity of the array surface.

[0050] Specifically, as a preferred embodiment, the specific arrangement structure of each array unit is as follows: The phased array antenna has an aperture size of 1500mm×1500mm, operates at the KA band, and has 641 antenna elements on the array surface, each element measuring 29mm×29mm.

[0051] First Inner Formation 22 Figure 3 As shown, the antenna is tilted at 45°, with the four corners of the square facing the positive axis, and arranged within a circular aperture with a diameter of 591.83 mm. Excluding the outermost row in each of the four directions of the tilt, there are 5 antennas arranged in the center in each direction, resulting in a square antenna array with 11 elements per row, for a total of 11 rows and 141 antenna elements.

[0052] Second Inner Formation 23 Figure 4 As shown, the antenna layout faces the center, with the number of elements increasing from the inside out; among them, the first layout 1 and the second layout 2 are symmetrically distributed in the 22.5° and 67.5° directions of the second quadrant 27 (e.g., Figure 3(As shown). This array has 4 rows. The first two rows each have 5 antenna elements, and the last two rows each have 7 antenna elements, for a total of 44 antenna elements in a single quadrant. Thanks to the symmetry of the four quadrants, the second inner array 23 has a total of 192 antenna elements.

[0053] First outer formation 24 Figure 5 As shown, the antenna layout faces the center and is distributed at 11.25°, 33.75°, 56.25°, and 78.75°. Each direction has four rows, with the column number counting starting from the side closest to 0° in the second quadrant (i.e., the closest to 0° is the first column). The specific element distribution is as follows... Figure 3 As shown: The third layout 3 in the 11.25° direction: the second, third and fourth columns of the first row each have 1 unit, the second and third columns of the second row each have 1 unit, the second and fifth columns of the third row each have 1 unit, and the first, third, fourth and fifth columns of the fourth row each have 1 unit. The fourth layout 4 in the 33.75° direction: the first and second rows each have 3 units starting from the second column, the third row has 4 units starting from the second column, and the first, third, fourth, and fifth columns of the fourth row each have 1 unit; The fifth layout 5 in the 56.25° direction: the first row has 3 units, the second row has only 1 unit in the second column, the third row has 1 unit in the first column, the second column is empty, and the third and fourth columns each have 1 unit, the fourth row has 2 units in the first two columns, the third column is empty, and the fourth column has 1 unit. The sixth layout 6 in the 78.75° direction: the first column of the first two rows is empty, and 3 units are set in each column starting from the second column. The third row has 4 units starting from the first column, and the fourth and fifth columns of the fourth row each have 1 unit.

[0054] Based on the symmetry of the four quadrants, the first outer array 24 has a total of 188 antenna elements.

[0055] Second outer formation 25 Figure 6 As shown, the antenna layout faces the center and is distributed at 3.99°, 12.88°, 28.13°, 39.37°, 50.63°, 61.87°, 73.12°, and 84.38°. Each direction has two rows, with the column number counting starting from the side closest to 0° in the second quadrant (i.e., the closest to 0° is the first column). The specific element distribution is as follows... Figure 3 As shown: The seventh layout 7 in the 3.99° direction: There are 2 rows in total, with 2 antenna elements in each row; The eighth layout 8 in the 12.88° direction: 1 unit in the second column of the first row, and 1 unit in the first and third columns of the second row; The ninth layout 9 in the 28.13° direction: the first row has 3 units, and the second row has only 1 unit in the second column; Layout 10 at 39.37°: Only the first row has 1 unit; Layout 11 at 50.63°: The first and second rows each have 3 units; The 12th layout in the 61.87° direction: The second and third columns of the first row each have 1 unit, and the second row is filled with 3 units; The 13th layout in the 73.12° direction: the first row and the first and second columns each have 1 unit, and the second row has only the third column with 1 unit; The fourteenth layout 14 in the 84.38° direction: the first row has only one unit in the third column, and the second row is filled with three units.

[0056] Based on the symmetry of the four quadrants, the second outer array 25 has a total of 120 antenna elements.

[0057] The layout of the above embodiment was compared with the layouts of the following three comparative examples to verify the degree of grating lobe suppression during phased array scanning at 8.5°. Figures 7 to 15 As shown, the specific layout and simulation results of this embodiment and the three comparative examples are as follows: Comparative Example 1: A full-array rectangular layout structure is used, such as... Figure 10 As shown, to ensure that the elements are as close as possible to each other without gaps, the entire array is filled within a size not exceeding 1500mm × 1500mm for each element, with each element measuring 29mm × 29mm. The simulation results of the full array gain pattern are as follows. Figure 11 As shown.

[0058] Comparative Example 2: A full-array layout structure rotating around a central point, as shown below. Figure 12 As shown, the rectangular antenna elements are rotated around the center to ensure they are as close as possible to each other without gaps. The entire array is filled with elements that are 1500mm × 1500mm in size, not exceeding the diameter of the circular aperture. Each element measures 29mm × 29mm. The simulation results of the full array gain pattern are shown below. Figure 13 As shown.

[0059] Comparative Example 3: A full-array layout structure rotating around a central point, as shown below. Figure 14 As shown, unlike Comparative Example 2, it is necessary to ensure that antenna elements of different radii at the same angle (e.g., 0°, 45°) are parallel to each other. When the radius is small, the antennas will overlap. The elements of different radii are arranged in pairs, while the central element is arranged parallel to the 0° direction. The entire array is filled within the size of each element, which is 1500mm × 1500mm and does not exceed the circular aperture. Each element is 29mm × 29mm. The simulation results of the full array gain pattern are shown below. Figure 15As shown.

[0060] The suppression levels of the 8.5° grating lobe in the phased array scanning under the above four conditions are shown in the table below:

[0061] As can be seen from the above, by adopting the array layout of this embodiment, the peak grating lobe of the antenna scanning is greatly reduced.

[0062] It should be noted that the trapezoidal or square structures mentioned above include not only standard trapezoidal or square structures, but also structures with external outlines that are approximately trapezoidal or square, as well as structures with internal spaces or protruding edges. Those skilled in the art can choose according to the actual situation, as long as the technical effect of ensuring the core gain requirement of the antenna can be achieved.

[0063] The terms “above,” “below,” and “within” as used above include the number itself; the terms “exceeding” and “excluding” do not include the number itself.

[0064] The present invention has been further described above with reference to specific embodiments. However, it should be understood that the specific descriptions herein should not be construed as limiting the substance and scope of the present invention. Various modifications made to the above embodiments by those skilled in the art after reading this specification are all within the scope of protection of the present invention. The various specific technical features described in the above embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the embodiments of the present invention will not further describe various possible combinations.

[0065] If the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

Claims

1. A spaceborne phased array low-grating-lobe antenna array, wherein a plurality of elements are arranged on the array surface, characterized in that, An inner ring and an outer ring are arranged outwardly from the center of the array, the units on the inner ring are arranged as a plurality of concentrated structures, the units on the outer ring are arranged as a plurality of non-uniform discrete structures, and the units are gradually sparse from the inner ring to the outer ring to destroy the periodicity of the array.

2. The space-borne phased array low grating lobe antenna array of claim 1, wherein, The inner ring comprises a first inner array part and a second inner array part arranged outwardly from the first inner array part, and the outer ring comprises a first outer array part arranged outwardly from the second inner array part and a second outer array part arranged outwardly from the first outer array part.

3. The space-borne phased array low grating lobe antenna array of claim 2, wherein, The number of unit rows on the first inner array part is greater than the number of unit rows on the second inner array part, the number of unit rows on the second inner array part is equal to the number of unit rows on the first outer array part, and the number of unit rows on the first outer array part is greater than the number of unit rows on the second outer array part.

4. The space-borne phased array low grating lobe antenna array of claim 2, wherein, The center of the array is taken as a cross point to sequentially form four quadrants, and the units in two adjacent quadrants are symmetrically arranged.

5. The space-borne phased array low grating lobe antenna array of claim 4, wherein, The quadrants comprise oppositely arranged first sub-arrays and second sub-arrays, and the second inner array part forms a trapezoidal structure on the first sub-arrays and the second sub-arrays.

6. The space-borne phased array low grating lobe antenna array of claim 4, wherein, The first inner array part forms a triangular structure on the quadrants to make the first inner array part have a square structure.

7. The space-borne phased array low grating lobe antenna array of claim 6, wherein, The first inner array part further comprises a convex strip located on a side of the first inner array part close to the second inner array part.

8. The space-borne phased array low grating lobe antenna array of claim 4, wherein, The first outer array part and the second outer array part are distributed along a plurality of angular directions on the quadrants, the angular directions are uniformly spaced along the radial direction of the quadrants, the number of unit rows on the first outer array part is set to four, the number of unit rows on the second outer array part is set to two, and the units in each angular direction are non-uniformly arranged in the row direction and form non-uniform empty columns.

9. The space-borne phased array low grating lobe antenna array of any one of claims 1 to 8, wherein, The array is arranged as a smooth profile structure.

10. The space-borne phased array low-sidelobe antenna array of any one of claims 1 to 8, characterized in that The center distance between two adjacent units is greater than one-half of the wavelength of the required grating lobe suppression condition.

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