A low-profile broadband circularly polarized millimeter-wave antenna with dumbbell-shaped slotted serial patches

Abstract

The present invention relates to a low-profile broadband circularly polarized millimeter-wave antenna with dumbbell-shaped slotted serial patches, which belongs to the field of microwave devices. It is composed of a metal radiation layer, an integrated waveguide layer and a ground layer; the metal radiation layer is provided with an eight-shaped gap and a rectangular gap, and the rectangular gap is provided with a stepped transition patch, a first radiation patch, a second radiation patch and a third radiation patch. Among them, the first radiation patch is composed of a square patch and a coupling patch, and the square patch is provided with a left oblique side, a right upper oblique side, a right lower oblique side, a first impedance gap and a second impedance gap; the third radiation patch has the same structure as the first radiation patch; the second radiation patch is provided with a cross-shaped gap in the middle position on the basis of the first radiation patch structure; the circularly polarized antenna proposed by the present invention solves the current problems of limited axial ratio bandwidth and high cross-section of circularly polarized antennas, and can well adapt to the antenna technology requirements of various devices and application scenarios.

Description

Technical Field

[0001] The invention belongs to the field of microwave devices and relates to a low-profile broadband circularly polarized millimeter-wave antenna with dumbbell-shaped slotted serial patches. Background Art

[0002] With the rapid development of wireless communication technology, the communication environment has become increasingly complex, placing higher demands on antenna performance. Structurally, antennas must be miniaturized, easy to integrate, and simple in structure. Performance demands include wide bandwidth, circular polarization, and high gain. Therefore, broadband circularly polarized antenna technology has become a research hotspot.

[0003] Traditional wireless communication devices are equipped with linearly polarized antennas, which radiate linearly polarized waves. These waves are easily affected by factors such as climate, environment, and the carrier's orientation. Circularly polarized antennas radiate circularly polarized waves with minimal polarization loss, allowing wireless communication devices to communicate normally without being restricted by antenna placement. These advantages have enormous application potential. Currently, circularly polarized antennas are widely used in various industries and scenarios. However, achieving circular polarization on broadband antennas while ensuring the circular polarization axial ratio bandwidth is a future research trend and a key indicator limiting the development of circularly polarized antennas.

[0004] Millimeter waves offer advantages such as short wavelengths, a wide frequency range, abundant spectrum resources, high data rates, and low latency. Currently, circularly polarized antennas in the millimeter wave band have complex structures and narrow impedance bandwidths, which cannot meet the requirements of current environments. Existing broadband circularly polarized antenna arrays are typically large and unsuitable for use in miniaturized wireless communication products.

[0005] In summary, existing millimeter-wave antennas cannot effectively solve problems such as limited axial ratio bandwidth, large loss, and high profile, and are therefore unable to adapt well to the technical requirements of various application scenarios for lightweight, low-profile, and broadband antenna payloads. Summary of the Invention

[0006] In order to achieve an axial ratio bandwidth of 5 GHz and solve the problem that existing antennas cannot simultaneously meet the requirements of broadband and low profile, the present invention provides a low-profile broadband circularly polarized millimeter-wave antenna with dumbbell-shaped slotted series patches.

[0007] A low-profile broadband circularly polarized millimeter-wave antenna with dumbbell-shaped slotted serial patches is a rectangular planar antenna; it includes a metal radiation layer 1, an integrated waveguide layer 2, and a ground layer 3 connected in sequence from top to bottom;

[0008] The metal radiation layer 1 is provided with an eight-shaped slit 9 and a rectangular slit 4 along its length. The eight-shaped slit 9 is located on one side of the metal radiation layer 1 in its length direction. The small diameter end of the eight-shaped slit 9 extends parallel to the edge of the width side of the metal radiation layer 1, and the large diameter end of the eight-shaped slit 9 corresponds to one side of the rectangular slit 4.

[0009] The rectangular gap 4 is sequentially connected with a stepped transition patch 5 and three or more radiating patches of the same structure, and the spacing between adjacent radiating patches is equal; the even-numbered radiating patches among the three or more radiating patches are provided with a cross-shaped gap;

[0010] The radiating patch is composed of parallel square patches 61 and strip-shaped coupling patches 65; the stepped transition patch 5 is connected to the square patch 61 in the adjacent radiating patch by a microstrip line, and the square patches 61 in the adjacent radiating patches are connected to each other by a microstrip line;

[0011] A left oblique edge 64 is provided at the upper left corner of the square patch adjacent to the coupling patch, and a first impedance slot 67 is provided on the side of the square patch 61 adjacent to the left oblique edge 64. An upper right oblique edge 62 is provided at the upper right corner of the square patch 61, and a lower right oblique edge 63 is provided at the lower right corner. A second impedance slot 66 is provided on the side of the square patch 61 between the upper right oblique edge 62 and the lower right oblique edge 63.

[0012] The dielectric substrate of the integrated waveguide layer 2 is provided with a plurality of evenly distributed metal cylinders 22; the evenly distributed metal cylinders 22 are in the shape of open rings, correspondingly surrounding the outer peripheries of the figure-eight gap 9 and the rectangular gap 4 on the metal radiation layer 1; the opening of the open ring is located at the small diameter end of the figure-eight gap 9;

[0013] The upper ends of the evenly distributed metal cylinders 22 are connected to the metal radiation layer 1, and the lower ends of the evenly distributed metal cylinders 22 are connected to the ground layer 3;

[0014] The small diameter end of the figure eight slot 9 on the metal radiation layer 1 is the input port of the low-profile broadband circularly polarized microstrip patch antenna;

[0015] The operating frequency band of the low-profile broadband circularly polarized millimeter wave antenna is 70 GHz-79.21 GHz, and the input reflection coefficient S is 2.5 GHz at 70 GHz-78.7 GHz. 11 The value is less than -10dB, the axial ratio is less than 3 in the range of 74.17GHz-79.21GHz, and the wavelength λ in the working frequency band of 70GHz-79.21GHz is 3.79mm-4.29mm.

[0016] The technical solutions are further defined as follows:

[0017] The rectangular gap 4 is provided with a stepped transition patch 5 connected in sequence and three radiating patches of the same structure, the three radiating patches being a first radiating patch 6, a second radiating patch 7 and a third radiating patch 8; the first radiating patch 6 is composed of a square patch 61 and a strip-shaped coupling patch 65 arranged in parallel; a left oblique edge 64 is provided at the upper left corner of the square patch 61 adjacent to the coupling patch 65, and the angles between the left oblique edge 64 and the adjacent two sides of the square patch 61 are equal; the square patch adjacent to the left cut corner 64 is provided with a left oblique edge 64. A first impedance slot 67 is provided on the side of the square patch 61; an upper right oblique side 62 is provided at the upper right corner, and a lower right oblique side 63 is provided at the lower right corner, and the angle between the upper right oblique side 62 and the two adjacent sides of the square patch 61 is equal to the angle between the lower right oblique side 63 and the two adjacent sides of the square patch 61; a second impedance slot 66 is provided on the side of the square patch between the upper right oblique side 62 and the lower right oblique side 63; the second radiation patch 7 is an even-numbered radiation patch, and a cross-shaped slot 71 is provided on the second radiation patch 7.

[0018] The size of the square patch 61 is 0.25λ×0.25λ, and the spacing between the square patch 61 and the coupling patch 65 is 0.05λ; the side length of the left hypotenuse 64 is 0.1λ, and the angles between the left hypotenuse 64 and the two adjacent sides of the square patch 61 are equal, both 45°; the side lengths of the upper right hypotenuse 62 and the lower right hypotenuse 63 are equal, both 0.075λ, and the angles between the upper right hypotenuse 62 and the two adjacent sides of the square patch 61 are equal. The angles between the sides are equal, both are 45°; the angles between the lower right oblique side 63 and the two adjacent side edges of the square patch 61 are equal, both are 45°; the size of the first impedance slot 67 is 0.025λ×0.075λ, and the size of the second impedance slot 66 is 0.05λ×0.065λ; the size of the horizontal slot in the cross-shaped slot 71 is 0.025λ×0.1λ, and the size of the vertical slot is 0.025λ×0.175λ.

[0019] The rectangular gap 4 is provided with a stepped transition patch 5 connected in sequence and four radiation patches with the same structure, and the four radiation patches are respectively the first radiation patch 6, the second radiation patch 7, the third radiation patch 8 and the fourth radiation patch 10; the second radiation patch 7 and the fourth radiation patch 10 are both even-numbered radiation patches, and the second radiation patch 7 and the fourth radiation patch 10 are respectively provided with a cross-shaped gap.

[0020] The spacing between adjacent radiation patches is 0.5λ, where λ is the wavelength of the antenna operating frequency band of 70-79.21 GHz.

[0021] The width of the gaps on both sides of the small diameter end of the figure eight slit 9 is the same, both of which are 0.1λ; the width of the gaps on both sides of the large diameter end of the figure eight slit 9 is the same, and the widths gradually increase, with the maximum width being 0.2λ.

[0022] The stepped transition patch 5 is stepped and includes an upper rectangular patch and a lower rectangular patch. The width of the upper rectangular patch is 0.075λ and the width of the lower rectangular patch is 0.15λ. The middle part of the upper rectangular patch is connected to the radiation patch through a microstrip. The two rectangular patches and the microstrip line constitute a stepped transition structure.

[0023] The low-profile broadband circularly polarized millimeter wave antenna has a length of 2.5λ-4.5λ and a width of 1.125λ-2λ.

[0024] The thickness of the integrated waveguide layer 2 is 0.0325λ, the material is Rogers 3003, and the dielectric constant is 3.0.

[0025] The radius of the metal cylinder 22 is 0.05λ.

[0026] Compared with the prior art, the beneficial technical effects of the present invention are embodied in the following aspects:

[0027] 1. The antenna of the present invention uses a 0.0325λ Rogers 3003 plate. By adopting the form of three patches connected in series and providing a coupling patch on the left side of the three patches, the impedance bandwidth of the antenna is improved, and a low-profile broadband antenna is realized. The antenna has an operating frequency band of 70 GHz-79.21 GHz and an impedance bandwidth of 9.21 GHz. This effectively solves the problems of current circularly polarized antennas such as limited axial ratio bandwidth, large loss, and high profile.

[0028] 2. The antenna of the present invention adopts a grounded coplanar waveguide (GCPW) structure for feeding, and then realizes the transition from the grounded coplanar waveguide (GCPW) structure to the substrate integrated waveguide (SIW) structure through a transition structure with an eight-shaped gap.

[0029] 3. The antenna features three radiating patches with left, upper right, and lower right bevels, respectively, to meet the basic current distribution requirements for circular polarization. Impedance slots of varying sizes are located on the left and right sides of the patch's center, increasing the antenna's axial bandwidth to 74.17-79.21 GHz.

[0030] 4. The antenna of the present invention adopts a grounded coplanar waveguide feeding method, transitions to a substrate integrated waveguide structure through an eight-shaped gap, improves the impedance bandwidth of the antenna by connecting multiple patches in series and loading coupling patches, and adjusts the circular polarization bandwidth of the antenna by cutting off three corners on three rectangular radiation patches to form oblique sides and opening two impedance slots, thereby overcoming the narrow bandwidth deficiency of microstrip circularly polarized antennas.

[0031] 5. The antenna of the present invention has the advantages of simple structure, easy integration, and miniaturization, which can well meet the needs of practical applications. The processing technology based on the dielectric substrate is mature, low-cost, simple, and has a high yield rate. It can meet the requirements of low-cost cross-section broadband circularly polarized microstrip patch antennas. In practical applications, it can be used in 5G wireless communications and automotive millimeter-wave radar, with a wide range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention.

[0033] Figure 2 Schematic diagram of substrate-integrated waveguide structure.

[0034] Figure 3 Schematic diagram of rectangular gap and figure eight gap structure.

[0035] Figure 4 It is a schematic diagram of the structure of the stepped transition patch, the first radiation patch, the second radiation patch and the third radiation patch.

[0036] Figure 5 This is a schematic structural diagram of the coupling patch of the first radiation patch, the oblique edges and gaps on the rectangular patch, and the cross-shaped gap on the second radiation unit.

[0037] Figure 6 This is a structural diagram of Example 2.

[0038] Figure 7 This is the axial ratio simulation result diagram of Example 1.

[0039] Figure 8 is the S parameter simulation result diagram of embodiment 1; S 11 is the reflection coefficient.

[0040] Figure 9 This is the axial ratio simulation result diagram of Example 2.

[0041] Figure 10 The S parameter simulation result diagram of the second embodiment; S 11 is the reflection coefficient.

[0042] Figure 1-7 Serial number: metal radiation layer 1, integrated waveguide layer 2, ground layer 3, rectangular gap 4, stepped transition patch 5, first radiation patch 6, second radiation patch 7, third radiation patch 8, figure eight gap 9, fourth radiation patch 10, square patch 61, upper right hypotenuse 62, lower right hypotenuse 63, left hypotenuse 64, coupling patch 65, second impedance gap 66, first impedance gap 67, cross gap 71. DETAILED DESCRIPTION

[0043] The present invention will be further described in detail below through embodiments with reference to the accompanying drawings.

[0044] Example 1

[0045] See also Figure 1 A low-profile broadband circularly polarized millimeter-wave antenna with dumbbell-shaped slotted serial patches is a rectangular planar antenna; it includes a metal radiation layer 1, an integrated waveguide layer 2 and a ground layer 3 connected in sequence from top to bottom.

[0046] The material of the integrated waveguide layer 2 is Rogers 3003, and the material of the metal radiation layer 1 and the ground layer 3 is copper.

[0047] See also Figure 3 The metal radiating layer 1 is provided with an eight-shaped slit 9 and a rectangular slit 4 along its length. The eight-shaped slit 9 is located on one side of the metal radiating layer 1 along its length. The smaller diameter end of the eight-shaped slit 9 extends parallel to the edge of one width side of the metal radiating layer 1, while the larger diameter end of the eight-shaped slit 9 corresponds to one side of the rectangular slit 4.

[0048] The width of the gaps on both sides of the small diameter end of the figure eight slit 9 is the same, both of which are 0.1λ; the width of the gaps on both sides of the large diameter end of the figure eight slit 9 is the same, and the widths gradually increase, with the maximum width being 0.2λ.

[0049] The size of the rectangular slot 4 is 0.35λ×1.5λ.

[0050] See also Figure 4 The rectangular gap 4 is connected in sequence with a stepped transition patch 5 and three radiation patches of the same structure, and the spacing between adjacent radiation patches is equal; the three radiation patches are the first radiation patch 6, the second radiation patch 7 and the third radiation patch 8; the second radiation patch 7 is an even-numbered radiation patch, and a cross-shaped gap 71 is opened on the second radiation patch 7.

[0051] The first radiation patch 6 is composed of parallel square patches 61 and strip-shaped coupling patches 65; the stepped transition patch 5 is connected to the square patches in the adjacent radiation patches by a microstrip line, and the square patches in the adjacent radiation patches are connected to each other by a microstrip line.

[0052] See also Figure 5, coupling patch 65 is parallel to the microstrip line. A left hypotenuse 64 is provided at the upper left corner of the square patch 61 adjacent to coupling patch 65. The angles between left hypotenuse 64 and the two adjacent sides of square patch 61 are equal. A first impedance slot 67 is provided on the side of the square patch adjacent to left cut corner 64. An upper right hypotenuse 62 is provided at the upper right corner of square patch 61, and a lower right hypotenuse 63 is provided at the lower right corner. The angles between upper right hypotenuse 62 and the two adjacent sides of square patch 61 are equal to the angles between lower right hypotenuse 63 and the two adjacent sides of square patch 61. A second impedance slot 66 is provided on the side of the square patch between upper right hypotenuse 62 and lower right hypotenuse 63.

[0053] The dimensions of square patch 61 are 0.25λ × 0.25λ, and the spacing between square patch 61 and coupling patch 65 is 0.05λ. The length of left hypotenuse 64 is 0.1λ, and the angles between left hypotenuse 64 and the two adjacent sides of square patch 61 are equal, both 45°. The lengths of upper right hypotenuse 62 and lower right hypotenuse 63 are equal, both 0.075λ, and the angles between upper right hypotenuse 62 and the two adjacent sides of square patch 61 are equal, both 45°. The angles between lower right hypotenuse 63 and the two adjacent sides of square patch 61 are equal, both 45°. The dimensions of first impedance slot 67 are 0.025λ × 0.075λ, and the dimensions of second impedance slot 66 are 0.05λ × 0.065λ.

[0054] The size of the horizontal slot in the cross-shaped slot 71 is 0.025λ×0.1λ, and the size of the vertical slot is 0.025λ×0.175λ.

[0055] The spacing between adjacent radiating patches is 0.5λ, where λ is the wavelength of the antenna operating frequency band of 70-79.21 GHz.

[0056] The stepped transition patch 5 is stepped and includes a rectangular patch and a lower rectangular patch. The width of the upper rectangular patch is 0.075λ and the width of the lower rectangular patch is 0.15λ. The middle part of the upper rectangular patch is connected to the first radiation patch 6 through a microstrip. The two rectangular patches and the microstrip line constitute a stepped transition structure.

[0057] The first radiating patch 6 primarily radiates electromagnetic waves between 70 GHz and 77 GHz, the second radiating patch 7 primarily radiates electromagnetic waves between 73 GHz and 77 GHz, and the third radiating patch 8 primarily radiates electromagnetic waves between 77 GHz and 79.21 GHz, forming the main radiating structure. However, the circular polarization performance of these three rectangular radiating elements is limited. To improve this performance, three corners are cut off to form beveled edges, and two impedance slots are provided.

[0058] See also Figure 245 evenly distributed metal cylinders 22 are installed on the dielectric substrate of the integrated waveguide layer 2; the 45 evenly distributed metal cylinders 22 are in the shape of an open ring, corresponding to the outer periphery of the figure-eight gap 9 and the rectangular gap 4 on the metal radiation layer 1; the opening of the open ring is located at the small diameter end of the figure-eight gap 9.

[0059] The radius of the metal cylinder 22 is 0.05λ, the height is 0.0325λ, and the spacing between adjacent metal cylinders 22 is 0.1λ-0.25λ. The upper ends of the 45 evenly distributed metal cylinders 22 are connected to the metal radiation layer 1, and the lower ends of several evenly distributed metal cylinders 22 are connected to the ground layer 3.

[0060] The small diameter end of the figure eight slot 9 on the metal radiation layer 1 is the input port of the low-profile broadband circularly polarized millimeter wave antenna;

[0061] The low-profile broadband circularly polarized millimeter-wave antenna of Example 1 was verified and simulated by calculation and electromagnetic field simulation. Figure 7 , the axial ratio of the antenna of Example 1 is less than 3dB at 74.17-79.21GHz; see Figure 8 The input reflection coefficient S of the antenna of Example 1 at 70GHz-78.7GHz is 11 The value is less than -10dB.

[0062] The impedance bandwidth of the antenna is improved by connecting three radiation patches with the same structure in series.

[0063] The three radiating patches have different cut angles at the upper left, upper right, and lower right, meeting the basic current distribution requirements for circular polarization. This enables both a circular polarization operating mode of 74.17 GHz to 79.21 GHz and a linear polarization operating mode of 70 GHz to 74.17 GHz.

[0064] Example 2

[0065] The low-profile broadband circularly polarized microstrip patch antenna of Example 2 is based on Example 1, with one additional radiating patch, that is, four radiating patches are connected in series. Other structures are the same as those of Example 1.

[0066] See also Figure 6 The rectangular gap 4 is provided with a stepped transition patch 5 connected in sequence and four radiating patches of the same structure. The four radiating patches are respectively a first radiating patch 6, a second radiating patch 7, a third radiating patch 8, and a fourth radiating patch 10. The second radiating patch 7 and the fourth radiating patch 10 are both even-numbered radiating patches, and each of the second radiating patch 7 and the fourth radiating patch 10 has a cross-shaped gap.

[0067] The first radiation patch 6 is mainly used to radiate 72.5GHz-77GHz electromagnetic waves, the second radiation patch 7 is mainly used to radiate 73GHz-77GHz electromagnetic waves, the third radiation patch 8 is mainly used to radiate 77GHz-78.5GHz electromagnetic waves, and the fourth radiation patch 10 is mainly used to radiate 68-71.2GHz electromagnetic waves.

[0068] Through calculation and electromagnetic field simulation, the low-profile broadband circularly polarized millimeter wave antenna of this embodiment 2 was verified and simulated. Figure 9 , the axial ratio of the antenna of Example 2 is less than 3dB at 74.2-77.5GHz; see Figure 10 , the S11 of the antenna of Example 2 is less than -10dB at 68GHz-71.2GHz and 72.5GHz-78.5GHz.

Claims

1. A dumbbell-shaped slotted, serially connected patch antenna with a low profile, broadband circular polarization, millimeter wave antenna, characterized by: The low-profile broadband circularly polarized millimeter wave antenna is a rectangular planar antenna; it comprises a metal radiation layer (1), an integrated waveguide layer (2), and a ground layer (3) connected in sequence from top to bottom; The metal radiation layer (1) is provided with an eight-shaped slit (9) and a rectangular slit (4) along the length direction; the eight-shaped slit (9) is located on one side of the length direction of the metal radiation layer (1); the small diameter end of the eight-shaped slit (9) extends in a parallel slit shape to the edge of the width side of the metal radiation layer (1); the large diameter end of the eight-shaped slit (9) corresponds to one side of the rectangular slit (4); The rectangular gap (4) is provided with a stepped transition patch (5) and three or more radiating patches with the same structure in sequence, and the spacing between adjacent radiating patches is equal; the even-numbered radiating patches among the three or more radiating patches are provided with a cross-shaped gap; The radiation patch is composed of parallel square patches (61) and strip-shaped coupling patches (65); the stepped transition patch (5) and the square patches in adjacent radiation patches are connected by microstrip lines, and the square patches (61) in adjacent radiation patches are connected by microstrip lines. A left oblique edge (64) is provided at the upper left corner of the square patch adjacent to the coupling patch, and a first impedance slot (67) is provided on the side of the square patch (61) adjacent to the left oblique edge (64); an upper right oblique edge (62) is provided at the upper right corner of the square patch (61), and a lower right oblique edge (63) is provided at the lower right corner; a second impedance slot (66) is provided on the side of the square patch (61) between the upper right oblique edge (62) and the lower right oblique edge (63); A plurality of evenly distributed metal cylinders (22) are provided on the dielectric substrate of the integrated waveguide layer (2); the evenly distributed metal cylinders (22) are in the shape of open rings, correspondingly surrounding the outer peripheries of the figure-eight slits (9) and the rectangular slits (4) on the metal radiation layer (1); the opening of the open ring is located at the small diameter end of the figure-eight slit (9); The upper ends of a plurality of evenly distributed metal cylinders (22) are connected to the metal radiation layer (1), and the lower ends of a plurality of evenly distributed metal cylinders (22) are connected to the grounding layer (3); The small diameter end of the figure eight slot (9) on the metal radiation layer (1) is the input port of the low-profile broadband circularly polarized millimeter wave antenna; The operating frequency band of the low-profile broadband circularly polarized millimeter wave antenna is 70 GHz-79.21 GHz, and the input reflection coefficient S is 2.5 GHz at 70 GHz-78.7 GHz. 11 The value is less than -10dB, the axial ratio is less than 3 in the range of 74.17GHz-79.21GHz, and the wavelength λ in the working frequency band of 70GHz-79.21GHz is 3.79mm-4.29mm.

2. The dumbbell-shaped slotted serial patch low-profile broadband circularly polarized millimeter-wave antenna according to claim 1, characterized in that: The rectangular gap (4) is provided with a stepped transition patch (5) connected in sequence and three radiating patches of the same structure, wherein the three radiating patches are respectively a first radiating patch (6), a second radiating patch (7) and a third radiating patch (8); the first radiating patch (6) is composed of a square patch (61) and a strip-shaped coupling patch (65) arranged in parallel; a left hypotenuse (64) is provided at the upper left corner of the square patch (61) adjacent to the coupling patch (65); the angles between the left hypotenuse (64) and the adjacent two sides of the square patch (61) are equal; the square patch adjacent to the left hypotenuse (64) is provided with a left hypotenuse (64) at the upper left corner. A first impedance slot (67) is provided on the side of the square patch (61); an upper right oblique side (62) is provided at the upper right corner of the square patch (61), and a lower right oblique side (63) is provided at the lower right corner, and the angle between the upper right oblique side (62) and the adjacent side of the square patch (61) is equal to the angle between the lower right oblique side (63) and the adjacent two sides of the square patch (61); a second impedance slot (66) is provided on the side of the square patch between the upper right oblique side (62) and the lower right oblique side (63); the second radiation patch (7) is an even-numbered radiation patch, and a cross-shaped slot (71) is provided on the second radiation patch (7).

3. The dumbbell-shaped slotted serial patch low-profile broadband circularly polarized millimeter-wave antenna according to claim 2, characterized in that: The size of the square patch (61) is 0.25λ×0.25λ, and the spacing between the square patch (61) and the coupling patch (65) is 0.05λ; the side length of the left hypotenuse (64) is 0.1λ, and the angles between the left hypotenuse (64) and the two adjacent sides of the square patch (61) are equal, both being 45°; the side lengths of the upper right hypotenuse (62) and the lower right hypotenuse (63) are equal, both being 0.075λ, and the angles between the upper right hypotenuse (62) and the square patch (61) are equal. The angles between two adjacent sides are equal, both being 45°; the angles between the lower right oblique side (63) and the two adjacent sides of the square patch (61) are equal, both being 45°; the size of the first impedance slot (67) is 0.025λ×0.075λ, and the size of the second impedance slot (66) is 0.05λ×0.065λ; the size of the horizontal slot in the cross-shaped slot (71) is 0.025λ×0.1λ, and the size of the vertical slot is 0.025λ×0.175λ.

4. The dumbbell-shaped slotted serial patch low-profile broadband circularly polarized millimeter-wave antenna according to claim 1, characterized in that: The rectangular gap (4) is provided with a stepped transition patch (5) connected in sequence and four radiating patches with the same structure, wherein the four radiating patches are respectively a first radiating patch (6), a second radiating patch (7), a third radiating patch (8) and a fourth radiating patch (10); the second radiating patch (7) and the fourth radiating patch (10) are respectively provided with a cross-shaped gap.

5. The low-profile broadband circularly polarized millimeter-wave antenna with dumbbell-shaped slotted serial patches according to claim 1, wherein the spacing between adjacent radiating patches is 0.5λ.

6. The dumbbell-shaped slotted serial patch low-profile broadband circularly polarized millimeter-wave antenna according to claim 1, characterized in that: The slit widths on both sides of the small diameter end of the figure eight slit (9) are the same, both of which are 0.1λ; the slit widths on both sides of the large diameter end of the figure eight slit (9) are the same, and both gradually increase, with the maximum slit width being 0.2λ.

7. The dumbbell-shaped slotted serial patch low-profile broadband circularly polarized millimeter-wave antenna according to claim 1, characterized in that: The step transition patch (5) is in a step shape and comprises an upper rectangular patch and a lower rectangular patch, wherein the width of the upper rectangular patch is 0.075λ and the width of the lower rectangular patch is 0.15λ; the middle portion of the upper rectangular patch is connected to the radiation patch via a microstrip, and the two rectangular patches and the microstrip line form a step transition structure.

8. The dumbbell-shaped slotted serial patch low-profile broadband circularly polarized millimeter-wave antenna according to claim 1, characterized in that: The low-profile broadband circularly polarized millimeter wave antenna has a length of 2.5λ-4.5λ and a width of 1.125λ-2λ.

9. The dumbbell-shaped slotted serial patch low-profile broadband circularly polarized millimeter-wave antenna according to claim 1, characterized in that: The thickness of the integrated waveguide layer (2) is 0.0325λ, the material is Rogers 3003, and the dielectric constant is 3.

0.

10. The dumbbell-shaped slotted serial patch low-profile broadband circularly polarized millimeter-wave antenna according to claim 1, characterized in that: The radius of the metal cylinder (22) is 0.05λ.

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