Dual-polarized high-gain high-isolation sunflower antenna

Abstract

The application discloses a dual-polarized high-gain high-isolation sunflower-shaped antenna. The antenna comprises a polytetrafluoroethylene base, a radiation patch, an impedance matching input microstrip line and a metal grounding plate. The upper surface of the base is provided with the radiation patch and the impedance matching input microstrip line. The radiation patch is composed of four circular patches, the centers of which are located at four corner points of a square. There is a circular defect in the center of each patch. There is a semicircular loading patch inwardly arranged at the upper end and the right end of the defect respectively. There is a strip-shaped defect outwardly arranged between the upper circular patch and the right circular patch. The upper and right circular patches are connected with one end of the impedance matching input microstrip line. There is a rectangular defect arranged on the two sides of the microstrip line at the connection position of the circular patch and the impedance matching input microstrip line. The lower surface of the polytetrafluoroethylene base is provided with the metal grounding plate. The dual-polarized high-gain high-isolation sunflower-shaped antenna has the advantages of dual-polarization, high-gain, high-isolation, simple structure and easy manufacturing.

Description

Technical Field

[0001] The present invention relates to the field of antennas, and in particular to a dual-polarization high-gain high-isolation sunflower-shaped antenna. Background Art

[0002] With the increasing use of mobile communications and the rapid development of wireless devices, the shortage of wireless broadband spectrum resources has become increasingly prominent. Furthermore, electronic devices are becoming increasingly integrated, and the physical size of electronic components used in high-frequency communications is shrinking. Dual-polarized antennas, as a new antenna technology, offer superior performance in suppressing multipath fading, improving channel capacity, and increasing spectral efficiency. Their most prominent advantage is that they can reduce the number of antennas required for a single directional base station. Therefore, dual-polarized antennas are highly competitive in communication systems.

[0003] Microstrip antennas are widely used in wireless communications due to their small size, ease of fabrication, low profile, ease of integration, and ease of array formation. Dual-polarization antenna characteristics are typically achieved through dual-port feeding. Inter-port isolation is a key performance parameter for dual-polarization antennas. Designing a specialized feeding network can directly and effectively improve port isolation. Differential feeding effectively excites both polarization modes, thereby improving port isolation. Arraying can significantly improve the overall antenna gain. Overall, designing high-gain, high-isolation dual-polarization microstrip antennas remains a significant challenge. Summary of the Invention

[0004] The purpose of the present invention is to provide a dual-polarization, high-gain, high-isolation microstrip patch antenna.

[0005] In order to achieve the above object, the technical solution of the present invention is as follows:

[0006] A dual-polarized, high-gain, high-isolation sunflower-shaped antenna comprising a tetrafluoroethylene substrate, a radiation patch, an impedance-matching input microstrip line, and a metal ground plate; the radiation patch and the impedance-matching input microstrip line are attached to the square top surface of the tetrafluoroethylene substrate, and the metal ground plate is attached to the square bottom surface of the tetrafluoroethylene substrate;

[0007] The radiation patch consists of four circular patches and two semicircular loading patches, and the centers of the four circular patches are respectively located at the four vertices of a square. A circular defect is hollowed out in the center of the radiation patch, and the center of the circular defect is located at the center of the square. Among the four circular patches, two adjacent circular patches are defect patches with two rectangular defects on the outer edges. Each notch patch is provided with a semicircular loading patch on the inner side along the outer edge of the circular defect, and is connected to the top edge of the polytetrafluoroethylene substrate through an impedance matching input microstrip line between the two rectangular defects. The rectangular defect, impedance matching input microstrip line and semicircular loading patch on each notch patch are mirror-symmetrical, and the mirror symmetry line is the line connecting the center of the notch patch and the center of the circular defect. A strip defect is opened between the two notch patches along the diagonal line of the square top surface of the polytetrafluoroethylene substrate, and one end of the strip defect passes through the radiation patch, while the other end does not pass through the circular defect in the radiation patch. The entire radiation patch and the two impedance matching input microstrip lines are mirror-symmetrical along the center line of the strip defect.

[0008] Preferably, the square top and square bottom of the polytetrafluoroethylene body have side lengths of 75 mm to 77 mm and a thickness of 0.75 to 0.77 mm.

[0009] Preferably, the radius of the four circular patches in the radiation patch is 13.7-13.9 mm, the diagonal length of the square formed by the centers of the four circular patches is 16 mm-18 mm, and the radiation patch is made of copper.

[0010] Preferably, the radius of the circular defect is 9 mm to 11 mm.

[0011] Preferably, the radius of the semicircular loading patch is 3.2 mm to 3.4 mm, and the center of the semicircular loading patch is located on the outer edge of the circular defect.

[0012] Preferably, the width of the strip defect is 0.9 mm to 1.1 mm, and the width of the patch between the strip defect and the circular defect is 0.4 mm to 0.6 mm.

[0013] Preferably, a microstrip line feeding connection is formed between the impedance matching input microstrip line and the radiation patch, and the characteristic impedance is 50Ω.

[0014] Preferably, the impedance matching input microstrip line has a length of 11.7 mm to 11.9 mm and a width of 2 mm to 4 mm, and is made of copper.

[0015] Preferably, the rectangular defects on both sides of the impedance matching input microstrip line have the same size, the width of the rectangular defects is 2 mm to 4 mm, and the distance between the bottom of the rectangular defects and the edge of the polytetrafluoroethylene substrate is 11.7 mm to 11.9 mm.

[0016] Preferably, the metal grounding plate has a side length of 75 mm to 77 mm, and its four edges completely coincide with the four edges of the square bottom surface of the polytetrafluoroethylene body, and is made of copper.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] The present invention adopts sunflower-shaped and array arrangement technology combined with microstrip design to design a dual-polarization high-gain and high-isolation sunflower-shaped antenna, which has the advantages of dual polarization, high gain, high isolation, low loss, simple structure, and easy production. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 Schematic diagram of the front structure of the dual-polarization high-gain and high-isolation sunflower antenna;

[0020] Figure 2 Schematic diagram of the back of the dual-polarization high-gain, high-isolation sunflower antenna;

[0021] Figure 3 Front view of the dual-polarization high-gain, high-isolation sunflower antenna;

[0022] Figure 4 Back view of the dual-polarization high-gain, high-isolation sunflower antenna;

[0023] Figure 5 Simulated and tested return loss of a dual-polarized high-gain, high-isolation sunflower antenna;

[0024] Figure 6 Simulated and tested dual-polarized high-gain, high-isolation sunflower antenna radiation direction;

[0025] Figure 7 Simulated and tested dual-polarization high-gain, high-isolation sunflower antenna gain. DETAILED DESCRIPTION

[0026] In order to make the above-mentioned objects, features and advantages of the present invention more clearly understood, the specific embodiments of the present invention are described in detail below with reference to the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below. The technical features in the various embodiments of the present invention can be combined accordingly without conflicting with each other.

[0027] For the convenience of description, the top surface of the polytetrafluoroethylene body 1 is defined as the front surface, and the bottom surface is defined as the bottom surface. Figure 1 The directions shown in the figure are used to define "up," "down," "left," and "right." However, it should be noted that in actual applications, the specific up, down, left, and right directions will vary depending on the spatial posture and viewing angle of the device, and this does not constitute a limitation. The specific structures of the aforementioned dual-polarization, high-gain, high-isolation sunflower antenna are described in detail below.

[0028] like Figure 1 As shown, the present invention provides a dual-polarization, high-gain, high-isolation sunflower-shaped antenna comprising a polytetrafluoroethylene substrate 1, a radiating patch 2, an impedance-matching input microstrip line 6, and a metal ground plane 8. The top and bottom surfaces of the polytetrafluoroethylene substrate 1 are both square. The radiating patch 2 and the impedance-matching input microstrip line 6 are attached to the square top surface of the polytetrafluoroethylene substrate 1, and the metal ground plane 8 is attached to the square bottom surface of the polytetrafluoroethylene substrate 1.

[0029] Continue to see Figure 1 As shown, the radiation patch 2 is composed of four circular patches and two semicircular loading patches 4, and the centers of the four circular patches are located at the four vertices of a square. It should be noted that the square where the centers of the four circular patches are located is not a physical component, but merely a reference introduced to facilitate the description of the positions of the four circular patches. The square formed by the centers of the four circular patches is rotated 90° relative to the square top surface of the tetrafluoroethylene base 1, that is, the two diagonals of the square are parallel to different sides of the square outer contour of the square top surface of the tetrafluoroethylene base 1.

[0030] Furthermore, the four circular patches in the aforementioned radiating patch 2 are not completely circular; they are hollowed out at designated locations to form corresponding defects. A circular defect 3 is hollowed out in the center of the radiating patch 2, with the center of this circular defect 3 located at the center of the square formed by the centers of the four circular patches. This circular defect 3 is a hollowed-out area with a circular edge. Furthermore, two adjacent circular patches among the four circular patches have defects on their outer edges, each with two rectangular defects 7, while the other two circular patches have defects only on one side of the circular defect 3. Each notched patch has a semicircular loading patch 4 positioned internally along the outer edge of the circular defect 3. An impedance-matching input microstrip line 6 connects the two rectangular defects 7 to the top edge of the Teflon substrate 1. The arc side of the semicircular loading patch 4 faces the center of the circular defect 3. It should be noted that the top edge of the Teflon substrate 1 refers to the square outer contour of the top surface. The outer edge of each notched patch refers to the arc-shaped edge on the other side of the arc opposite the circular defect 3. Furthermore, an open rectangular defect 7 is provided on each side of the impedance matching input microstrip line 6 on each notch patch, and the impedance matching input microstrip line 6 between the two rectangular defects 7 needs to be connected to the top edge of the PTFE substrate 1 closest to the rectangular defect 7. Figure 1 As shown, the notch patch located at the top is connected to the upper edge of the top surface of the PTFE substrate 1 via an impedance matching input microstrip line 6, while the notch patch located on the right is connected to the right edge of the top surface of the PTFE substrate 1 via an impedance matching input microstrip line 6. However, the circular patches located at the bottom and on the left do not require the rectangular defect 7 or the impedance matching input microstrip line 6. Two semicircular loading patches 4 are located above and to the right of the circular defect 3, respectively.

[0031] The rectangular defect 7, impedance matching input microstrip line 6, and semicircular loading patch 4 on each notch patch are all mirror-symmetrical. For each notch patch, the mirror-symmetrical line between the rectangular defect 7, impedance matching input microstrip line 6, and semicircular loading patch 4 is the line connecting the center of the notch patch and the center of the circular defect 3. In addition, a strip defect 5 is provided between the two notch patches, with the long axis of the strip defect 5 running along the diagonal of the square top surface of the polytetrafluoroethylene substrate 1. Figure 1 As shown, one end of the strip defect 5 passes through the radiating patch 2, while the other end does not pass through the circular defect 3 within the radiating patch 2. That is, the other end of the strip defect 5 still retains a circular arc patch of a certain width, rather than directly connecting to the circular defect 3. The entire radiating patch 2 is hollow sunflower-shaped. The entire radiating patch 2 and the two impedance-matching input microstrip lines 6 are mirror-symmetrical along the centerline of the long axis of the strip defect 5. In other words, the entire radiating patch 2 and the two impedance-matching input microstrip lines 6 are mirror-symmetrical along the diagonal line from the upper right corner to the lower left corner of the square top surface of the polytetrafluoroethylene substrate 1.

[0032] like Figure 2 As shown, the back structure of the dual-polarization high-gain high-isolation sunflower-shaped antenna is shown. The back of the antenna only has a rectangular metal ground plate 8. The metal ground plate 8 is attached to the bottom surface of the polytetrafluoroethylene substrate 1, and the edges of the four sides just coincide with the edges of the square back of the polytetrafluoroethylene substrate 1.

[0033] It should be noted that the radiating patch 2 and the impedance-matching input microstrip line 6 of the present invention are actually manufactured as a single piece. For ease of description, the radiating patch is broken down into different sub-structures. However, in actual manufacturing, the radiating patch 2 and the impedance-matching input microstrip line 6 can be directly manufactured as a single piece, without the need for separate processing and subsequent assembly.

[0034] In the above-mentioned dual-polarization high-gain, high-isolation sunflower-shaped antenna, the structural parameters and materials of each component can be optimized and adjusted according to actual needs. In an embodiment of the present invention, the structural parameters and materials are preferably as follows: the side lengths of the square top and square bottom of the polytetrafluoroethylene substrate 1 are 75mm to 77mm, the thickness is 0.75 to 0.77mm, and the material is polytetrafluoroethylene. The radius of the four circular patches in the radiation patch 2 is 13.7 to 13.9mm, and the diagonal length of the square formed by the centers of the four circular patches is 16mm to 18mm. The material is copper. The radius of the circular defect 3 is 9mm to 11mm. The radius of the semicircular loading patch 4 is 3.2mm to 3.4mm, and its center is located on the outer edge of the circular defect 3. The width of the strip defect 5 is 0.9mm to 1.1mm, and the patch width between the strip defect 5 and the circular defect 3, that is, the shortest distance between the strip defect 5 and the circular defect 3, is 0.4mm to 0.6mm. The impedance-matching input microstrip line 6 forms a microstrip line feed connection with the radiating patch 2, with a characteristic impedance of 50Ω. The impedance-matching input microstrip line 6 has a length of 11.7mm to 11.9mm and a width of 2mm to 4mm, and is made of copper. The rectangular defects 7 on either side of the impedance-matching input microstrip line 6 are identical in size, with a width of 2mm to 4mm. The minimum distance between the bottom of the rectangular defect 7 and the edge of the polytetrafluoroethylene substrate 1 is 11.7mm to 11.9mm. The metal ground plane 8 has a square outer contour with sides of 75mm to 77mm, and its four edges completely overlap with the four edges of the square bottom surface of the polytetrafluoroethylene substrate 1. It is made of copper.

[0035] The dual-polarization high-gain high-isolation sunflower-shaped antenna is applied to a specific example to demonstrate its technical effect.

[0036] Example 1

[0037] In this embodiment, the structure of the dual-polarized high-gain high-isolation sunflower antenna is as described above. Figure 1 and Figure 2 The specific parameters and materials of each component are as follows:

[0038] Polytetrafluoroethylene (PTFE) substrate 1, made of a material with a dielectric constant of 2.2, serves as the microstrip substrate for the entire antenna. The square top and bottom sides of the PTFE substrate 1 are both 76 mm long, and the thickness is 0.76 mm. The radius of the four circular patches in radiating patch 2 is 13.8 mm, and the diagonal length of the square formed by the centers of the four circular patches is 17 mm, meaning the distance between the centers of the two opposing circular patches is 17 mm. Radiating patch 2 is made of copper. The radius of circular defect 3 is 10 mm. The radius of semicircular loading patch 4 is 3.3 mm, with its center located on the outer edge of circular defect 3. The width of strip defect 5 is 1 mm, and the patch width between strip defect 5 and circular defect 3, i.e., the shortest distance between strip defect 5 and circular defect 3, is 0.5 mm. The impedance-matching input microstrip line 6 forms a microstrip feed connection with radiating patch 2, with a characteristic impedance of 50 Ω. The impedance-matching input microstrip line 6 is 11.8 mm long and 3 mm wide, and is made of copper. The rectangular defects 7 on either side of the impedance-matching input microstrip line 6 are identical in size and 3 mm wide, with the minimum distance between the bottom of the defect and the edge of the polytetrafluoroethylene substrate 1 being 11.8 mm. The metal ground plate 8, made of copper, has a square outer contour with sides measuring 76 mm, and its edges completely overlap the edges of the square bottom surface of the polytetrafluoroethylene substrate 1.

[0039] Figure 4 The following is a photo of the dual-polarization high-gain high-isolation sunflower-shaped antenna fabricated in this embodiment. Software was used to simulate the return loss curve and radiation characteristics of the dual-polarization high-gain high-isolation sunflower-shaped antenna in this embodiment, and measurements were taken of the fabricated antenna. The return loss curve of the dual-polarization high-gain high-isolation sunflower-shaped antenna is shown in Figure 1. Figure 5 .Depend on Figure 3 It can be seen that the antenna resonant frequency in the software simulation is 5.8GHz, the -10dB bandwidth is 0.08GHz (5.76-5.84GHz), and the isolation |S 21 |are all less than -25.8dB, isolation at 5.82GHz|S 21 The reflection coefficients |S of the two ports measured at 5.74-5.82GHz and 5.74-5.81GHz respectively are -37.4dB. 11(22) | is less than -10dB, and the bandwidths are 1.38% and 1.3%, respectively, which closely matches the simulation results. The measured isolation between the two ports within the operating bandwidth is greater than 25dB, reaching 30dB at 5.8GHz. The measured isolation between the two feed ports is almost identical to the simulated isolation. Figure 6The figure shows the radiation pattern of the dual-polarization high-gain, high-isolation sunflower antenna. The cross-polarization level measured in the XOZ and YOZ planes is 20 dB lower than the co-polarization level. Figure 7 Figure 3.2 shows the simulated and measured gain of a dual-polarized, high-gain, high-isolation sunflower antenna (Sim.Port represents the simulated port, and Mea.Port represents the measured port). The measured antenna achieves a peak gain of 11.3 dBi at 5.8 GHz. The slight discrepancy between the simulated and experimental results is due to manufacturing and testing errors.

[0040] The embodiment described above is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Persons skilled in the art may make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, any technical solution obtained by equivalent substitution or equivalent transformation falls within the scope of protection of the present invention.

Claims

1. A dual-polarization high-gain high-isolation sunflower-shaped antenna, characterized in that: It comprises a polytetrafluoroethylene substrate (1), a radiation patch (2), an impedance matching input microstrip line (6) and a metal grounding plate (8); the radiation patch (2) and the impedance matching input microstrip line (6) are attached to the square top surface of the polytetrafluoroethylene substrate (1), and the metal grounding plate (8) is attached to the square bottom surface of the polytetrafluoroethylene substrate (1); The radiation patch (2) is composed of four circular patches and two semicircular loading patches (4), and the centers of the four circular patches are respectively located at the four vertices of a square. A circular defect (3) is hollowed out at the center of the radiation patch (2), and the center of the circular defect (3) is located at the center of the square. Two adjacent circular patches among the four circular patches are defect patches with two rectangular defects (7) on their outer edges. Each notch patch is provided with a semicircular loading patch (4) on the inner side along the outer edge of the circular defect (3), and is connected to the top surface edge of the polytetrafluoroethylene substrate (1) through an impedance matching input microstrip line (6) between the two rectangular defects (7). The rectangular defect (7), the impedance matching input microstrip line (6), and the semicircular loading patch (4) on each notch patch are mirror-symmetrical, and the mirror symmetry line is the line connecting the center of the notch patch and the center of the circular defect (3); a strip defect (5) is provided between the two notch patches along the diagonal line of the square top surface of the polytetrafluoroethylene substrate (1), and one end of the strip defect (5) passes through the radiation patch (2), while the other end does not pass through the circular defect (3) in the radiation patch (2); the entire radiation patch (2) and the two impedance matching input microstrip lines (6) are mirror-symmetrical along the center line of the strip defect (5).

2. A dual-polarization high-gain high-isolation sunflower-shaped antenna as claimed in claim 1, characterized in that The side lengths of the square top and square bottom of the polytetrafluoroethylene body (1) are 75 mm to 77 mm, and the thickness is 0.75 to 0.77 mm.

3. A dual-polarization high-gain high-isolation sunflower-shaped antenna as claimed in claim 1, characterized in that The radius of the four circular patches in the radiation patch (2) is 13.7-13.9 mm, the diagonal length of the square formed by the centers of the four circular patches is 16 mm-18 mm, and the material of the radiation patch (2) is copper.

4. A dual-polarization high-gain high-isolation sunflower-shaped antenna as claimed in claim 1, characterized in that The radius of the circular defect (3) is 9 mm to 11 mm.

5. A dual-polarization high-gain high-isolation sunflower-shaped antenna as claimed in claim 1, characterized in that The radius of the semicircular loading patch (4) is 3.2 mm to 3.4 mm, and the center of the semicircular loading patch (4) is located on the outer edge of the circular defect (3).

6. A dual-polarization high-gain high-isolation sunflower-shaped antenna as claimed in claim 1, characterized in that The width of the strip-shaped defect (5) is 0.9 mm to 1.1 mm, and the width of the patch between the strip-shaped defect (5) and the circular defect (3) is 0.4 mm to 0.6 mm.

7. A dual-polarization high-gain high-isolation sunflower-shaped antenna as claimed in claim 1, characterized in that A microstrip line feeding connection is formed between the impedance matching input microstrip line (6) and the radiation patch (2), and the characteristic impedance is 50Ω.

8. The dual-polarization high-gain high-isolation sunflower-shaped antenna according to claim 1, characterized in that The impedance matching input microstrip line (6) has a length of 11.7 mm to 11.9 mm and a width of 2 mm to 4 mm, and the material of the impedance matching input microstrip line (6) is copper.

9. The dual-polarization high-gain high-isolation sunflower-shaped antenna according to claim 1, characterized in that The rectangular defects (7) on both sides of the impedance matching input microstrip line (6) have the same size, the width of the rectangular defect (7) is 2 mm to 4 mm, and the distance between the bottom of the rectangular defect (7) and the edge of the polytetrafluoroethylene substrate (1) is 11.7 mm to 11.9 mm.

10. The dual-polarization high-gain high-isolation sunflower-shaped antenna according to claim 1, characterized in that The metal grounding plate (8) has a side length of 75 mm to 77 mm, and its four edges completely overlap with the four edges of the square bottom surface of the polytetrafluoroethylene body (1), and its material is copper.

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