Circularly polarized co-boresight patch antenna

Abstract

The application discloses a circularly polarized co-aperture patch antenna, which is characterized in that a low-frequency rhombic patch loaded with an L-shaped slot and a slot stub is stacked on a high-frequency sequentially rotated feed patch array arranged at a small interval, the L-shaped slot and the slot stub are used to suppress high-frequency and low-frequency induced currents, and adjust the matching and axial ratio of the low-frequency antenna, and an open-circuit stub loaded at a port is used to isolate the high-frequency port from the low-frequency port, so that the circularly polarized co-aperture patch antenna with the characteristics of a low profile, a small size and a low mutual coupling between high-frequency and low-frequency units is realized.

Description

Technical Field

[0001] This invention relates to a wireless communication device, and more particularly to a circularly polarized common-aperture patch antenna. Background Technology

[0002] Common-aperture patch antennas, by integrating multiple patch elements within the same physical aperture, solve the problems of bulky size and severe coupling interference in traditional multi-patch antenna systems. They offer multiple advantages, including high integration, small size, and low cost, making them suitable for 5G / 6G communications, MIMO terminals, radar, and phased array systems. From a polarization perspective, common-aperture patch antennas are divided into linearly polarized and circularly polarized types. Linearly polarized common-aperture patch antennas are used in scenarios with relatively stable polarization, requiring only consideration of port coupling and independent radiation capabilities between multiple elements during implementation. Circularly polarized common-aperture patch antennas are used in scenarios where polarization direction is easily deflected or has diverse polarization directions. Their implementation requires consideration not only of port coupling and independent radiation capabilities between multiple elements but also of axial ratio stability. Therefore, circularly polarized common-aperture patch antennas have significant engineering value, and their design should consider axial ratio, coupling, and the radiation performance of each element.

[0003] There are two main design methods for existing circularly polarized co-aperture patch antennas. The first method involves arranging multiple patches of different shapes or sizes in the same plane using orthogonal, adjacent, or nested arrangements to achieve a dual-frequency circularly polarized co-planar patch antenna. However, this method suffers from problems such as a large planar size, lack of consideration for isolation between high- and low-frequency antenna elements, and large spacing between high-frequency antenna elements, which is detrimental to array formation. The second method involves a stacked circularly polarized co-aperture patch antenna formed by low-frequency elements and a large-spacing, sequentially rotated-fed circularly polarized patch array. This method avoids increasing the planar size, but suffers from problems such as a high profile and large spacing between high-frequency antenna elements, which is detrimental to array operation. Therefore, it is necessary to propose a circularly polarized co-aperture patch antenna that, under the condition of a small-spacing arrangement of a high-frequency sequentially rotated-fed circularly polarized patch array, achieves a low profile, small size, and maintains isolation to obtain low mutual coupling between elements. Summary of the Invention

[0004] Purpose of the invention: In view of the above-mentioned prior art, a circularly polarized common-aperture patch antenna is proposed, which achieves low profile, small size and low mutual coupling between high and low frequency elements under the condition of high-frequency sequential rotation-fed circularly polarized patch array with small spacing.

[0005] Technical Solution: A circularly polarized common-aperture patch antenna includes a low-frequency radiator, a high-frequency radiator, a low-frequency microstrip feed line, and a high-frequency microstrip feed line. The low-frequency radiator includes a slot-loaded rhomboid metal patch. The high-frequency radiator includes a rotating array of diagonally cut square metal patches with oblique slots. The low-frequency radiator is positioned above the high-frequency radiator. A low-frequency signal is fed into the low-frequency radiator from the low-frequency microstrip feed line, and a high-frequency sequentially rotating signal is fed into the high-frequency radiator from the high-frequency microstrip feed line. Under the combined action of the low-frequency radiator and the high-frequency radiator, a dual-frequency circularly polarized common-aperture patch antenna is formed.

[0006] Furthermore, the circularly polarized common-aperture patch antenna includes, from top to bottom, a first metal layer, a top dielectric substrate, a second metal layer, an intermediate dielectric substrate, a metal ground, a bottom dielectric substrate, a bottom metal layer, and a metal probe group; the first metal layer is located on the upper surface of the top dielectric substrate, the second metal layer is located on the upper surface of the intermediate dielectric substrate, the metal ground is located on the upper surface of the bottom dielectric substrate, and the bottom metal layer is located on the lower surface of the bottom dielectric substrate; air layers are respectively provided between the top dielectric substrate and the second metal layer, and between the second metal layer and the metal ground.

[0007] Furthermore, the first metal layer is a rhomboid metal patch loaded with a groove, the groove including an outer equilateral L-shaped groove, a horizontal groove branch, a vertical groove branch, and an inner equilateral L-shaped groove; wherein, the inner equilateral L-shaped groove is parallel to the outer equilateral L-shaped groove, and the inflection points of the outer equilateral L-shaped groove and the inner equilateral L-shaped groove are both located at the upper right of the rhomboid metal patch; the horizontal groove branch is located on the vertical groove side of the outer equilateral L-shaped groove, and the vertical groove branch is located on the horizontal groove side of the outer equilateral L-shaped groove.

[0008] Furthermore, the second metal layer includes four diagonally chamfered square metal patches with beveled grooves, the bevels being located at both ends of the bevels; the four diagonally chamfered square metal patches are distributed in a rotating manner.

[0009] Furthermore, the bottom metal includes four stepped metal strips distributed in a rotating manner and one horizontal stepped metal strip; the first branch is vertically loaded on the four stepped metal strips, and the second branch is vertically loaded on the horizontal stepped metal strip.

[0010] The rhombus-shaped metal patch and the horizontal stepped metal strip are connected by a first metal probe, with the connection point located on the vertical center line of the rhombus-shaped metal patch; the diagonally cut square metal patch and the stepped metal strip are connected one-to-one by four second metal probes, with the connection points located on the horizontal or vertical center lines of the four diagonally cut square metal patches.

[0011] Furthermore, the four sides of the rhomboid metal patch are curved, with an arc length of 0.29. lL -0.3 l L between, l L This is the free-space wavelength corresponding to the operating frequency of the low-frequency antenna.

[0012] Furthermore, the side length of the outer equilateral L-shaped groove is 0.11. l L -0.12 l L Between these intervals, the length of the horizontal trough branch is 0.07. l L -0.08 l L Between these, the length of the vertical groove branch is 0.03. l L -0.04 l L Between these points, the side length of the inner equilateral L-shaped groove is 0.12. l L -0.13 l L between.

[0013] Furthermore, the center-to-center spacing between adjacent diagonally cut square metal patches is 0.5. l H , l H The free-space wavelength corresponds to the operating frequency of the high-frequency unit.

[0014] Furthermore, the length of the first branch is 0.14. l L -0.15 l L Between, the length of the second branch is 0.13. l H -0.14 l H between.

[0015] Beneficial Effects: Existing circularly polarized common-aperture patch antennas suffer from one or more of the following problems: large planar size, high profile, lack of consideration for isolation between high- and low-frequency antenna elements, and large spacing between high-frequency antenna elements, which is not conducive to array formation. This invention stacks low-frequency rhomboid patches loaded with L-shaped slots and slot stubs onto a finely spaced array of high-frequency sequentially rotated-fed patches. Utilizing the suppression effect of the L-shaped slots and slot stubs on high and low-frequency induced currents, as well as their effect on adjusting the matching and axial ratio of the low-frequency antenna, combined with the isolation effect of open-circuit stubs loaded at the ports between high and low frequency ports, a circularly polarized common-aperture patch antenna with low profile, small size, and low mutual coupling between high and low frequency elements is achieved.

[0016] Specifically, the low-frequency rhomboid patch contains two parallel equilateral L-shaped slots located at the upper right of the rhomboid metal patch. These two slots work together to suppress high- and low-frequency induced currents, reducing their adverse effects on the radiation of the high- and low-frequency antennas. Simultaneously, the outer equilateral L-shaped slot can adjust the impedance matching of the low-frequency antenna, while the inner equilateral L-shaped slot can adjust the disturbance to the low-frequency antenna's operating mode, achieving circular polarization performance.

[0017] The horizontal and vertical slot stubs within the low-frequency rhomboid patch are located on the vertical and horizontal slot edges of the outer equilateral L-shaped slot, respectively. When the low-frequency antenna is excited, the adjustable horizontal and vertical slot stubs disturb the operating mode of the low-frequency antenna, thereby enabling the low-frequency antenna to achieve a better circular polarization effect.

[0018] The four sides of the rhombus patch are curved, and the radiation deflection angle of the high-frequency antenna can be adjusted by changing the arc length.

[0019] Open-circuit stubs are loaded on both the high-frequency and low-frequency feeders to suppress coupling signals between the high-frequency and low-frequency ports and achieve low port mutual coupling between the high-frequency and low-frequency units. Attached Figure Description

[0020] Figure 1 This is a schematic cross-sectional view of the circularly polarized common-aperture patch antenna of the present invention.

[0021] Figure 2 This is a schematic diagram of the first metal layer structure of the circularly polarized common-aperture patch antenna of the present invention;

[0022] Figure 3 This is a schematic diagram of the second metal layer structure of the circularly polarized common-aperture patch antenna of the present invention;

[0023] Figure 4 This is a schematic diagram of the underlying metal structure of the circularly polarized common-aperture patch antenna of the present invention;

[0024] Figure 5 The following is a simplified diagram of the average current distribution at 3.5 GHz for the circularly polarized common-aperture patch antenna before and after decoupling, when only the low-frequency element is excited. (a) corresponds to before decoupling, and (b) corresponds to after decoupling.

[0025] Figure 6 The following is a simplified diagram of the average current distribution at 4.9 GHz for the circularly polarized common-aperture patch antenna before and after decoupling, when only high-frequency element 1 is excited. (a) corresponds to before decoupling, and (b) corresponds to after decoupling.

[0026] Figure 7 Simulation of the circularly polarized common-aperture patch antenna before and after decoupling for an example. S Parameter comparison, where (a) corresponds to the simulation before decoupling. S Parameter (b) corresponds to the decoupled simulation. Sparameter;

[0027] Figure 8 The simulation axial ratio comparison of the circularly polarized common aperture patch antenna before and after decoupling is shown in the example, where (a) corresponds to the simulation axial ratio before decoupling and (b) corresponds to the simulation axial ratio after decoupling.

[0028] Figure 9 For the example, the simulated radiation patterns of the circularly polarized common-aperture patch antenna before and after decoupling are compared when only the low-frequency element is excited. (a) corresponds to the simulated radiation pattern of the phi=0° plane before decoupling, (b) corresponds to the simulated radiation pattern of the phi=90° plane before decoupling, (c) corresponds to the simulated radiation pattern of the phi=0° plane after decoupling, and (d) corresponds to the simulated radiation pattern of the phi=90° plane after decoupling.

[0029] Figure 10 The following is a comparison of the simulated radiation patterns before and after decoupling when only the high-frequency element is excited in the circularly polarized common-aperture patch antenna of the embodiment. (a) corresponds to the simulated radiation pattern of the phi=0° plane before decoupling, (b) corresponds to the simulated radiation pattern of the phi=90° plane before decoupling, (c) corresponds to the simulated radiation pattern of the phi=0° plane after decoupling, and (d) corresponds to the simulated radiation pattern of the phi=90° plane after decoupling. Detailed Implementation

[0030] The invention will now be further explained with reference to the accompanying drawings.

[0031] like Figure 1 As shown, a circularly polarized common-aperture patch antenna is composed of a first metal layer 1, a top dielectric substrate 2, a second metal layer 3, an intermediate dielectric substrate 4, a metal ground 5, a bottom dielectric substrate 6, a bottom metal layer 7, a metal probe group, and a fixing structure.

[0032] The first metal layer 1 is located on the upper surface of the top dielectric substrate 2. For example... Figure 2 As shown, the first metal layer 2 is a rhomboid metal patch 101 loaded in a groove. The groove consists of four parts: an outer equilateral L-shaped groove 102, a horizontal groove branch 103, a vertical groove branch 104, and an inner equilateral L-shaped groove 105. The four sides of the rhomboid metal patch 101 are arcs with an arc length of 0.29 mm. l L -0.3 l L between, l L This refers to the free-space wavelength corresponding to the operating frequency of the low-frequency antenna. The inflection point of the outer equilateral L-shaped slot 102 is located at the upper right of the rhombic metal patch 101, with its two sides parallel to the vertical and horizontal center lines of the rhombic metal patch 101, respectively, and a side length of 0.11. l L -0.12 lL Between. The horizontal slot branch 103 is located on the vertical slot side of the outer equilateral L-shaped slot 102, and its length is between 0.07. l L -0.08 l L Between; the vertical groove branch 104 is located on the horizontal groove side of the outer equilateral L-shaped groove 102, and its length is between 0.03 l L -0.04 l L Between. The inner equilateral L-shaped groove 105 is parallel to the outer equilateral L-shaped groove 102, and the inflection point is also located at the upper right of the rhomboid metal patch 101, with a side length of 0.12. l L -0.13 l L between.

[0033] The second metal layer 3 is located on the upper surface of the intermediate dielectric substrate 4. For example... Figure 3 As shown, the second metal layer 3 includes four diagonally chamfered square metal patches 301 with etched slant grooves 302. On each diagonally chamfered square metal patch 301, a pair of chamfered corners are located at both ends of the slant groove. The four diagonally chamfered square metal patches 301 are rotated, meaning the four pairs of chamfered corners are rotated relative to the four slant grooves, and the center-to-center distance between adjacent patches is 0.5. l H , l H The free-space wavelength corresponds to the operating frequency of the high-frequency unit.

[0034] Metal ground 5 is located on the upper surface of the bottom dielectric substrate 6, and bottom metal 7 is located on the lower surface of the bottom dielectric substrate 6. For example... Figure 4 As shown, the bottom metal 7 comprises four rotating stepped metal strips 701 and one horizontal stepped metal strip 702. The four rotating stepped metal strips 701 are each vertically loaded with a length of 0.14 mm. l L -0.15 l L Branch 703 connects to the abrupt change in width of the stepped metal strip 701; a vertically loaded strip with a length of 0.13 is attached to the horizontal stepped metal strip 702. l H -0.14 l H Branches 704. Four stepped metal strips 701 arranged in a rotating relationship serve as high-frequency ports one to four, respectively, while a horizontal stepped metal strip 702 serves as a low-frequency port.

[0035] Metal probe 801 is used to connect the rhomboid metal patch 101 and the horizontal stepped metal strip 702, with the connection point located on the vertical center line of the rhomboid metal patch 101. Four metal probes 802 are used to connect, respectively, the diagonally chamfered square metal patches 301 and the stepped metal strips 701 in a rotating distribution relationship, with the connection points located on the horizontal or vertical center lines of the four diagonally chamfered square metal patches 301.

[0036] The fixing structure includes bolts 901 that pass sequentially through the bottom metal 7, the bottom dielectric substrate 6, the metal ground 5, the intermediate dielectric substrate 4, and the top dielectric substrate 2 from both sides, and nuts 902 connected to the ends, as well as bolts 901 that are respectively disposed between the top dielectric substrate 2, the intermediate dielectric substrate 4, and the metal ground 5 and fitted onto each bolt 901, for forming air layers between the top dielectric substrate 2 and the second metal layer 3, and between the second metal layer 3 and the metal ground 5.

[0037] The slot-loaded rhomboid metal patch 101, the top dielectric substrate 2, the intermediate dielectric substrate 4, and the metal ground 5 together constitute a low-frequency radiator. Four identical etched oblique slots 302 with diagonally cut square metal patches 301, the intermediate dielectric substrate 4, and the metal ground 5 together constitute a high-frequency radiator, corresponding to units one through four respectively. The horizontal stepped metal strip 702 of the loaded stub 704, the metal ground 5, and the bottom dielectric substrate 6 constitute a low-frequency microstrip feed line. The four rotating stepped metal strips 701 of the loaded stub 703, the metal ground 5, and the bottom dielectric substrate 6 constitute a high-frequency microstrip feed line.

[0038] For the above-mentioned circularly polarized common-aperture patch antenna, the low-frequency signal and the high-frequency sequential rotation signal are fed in from the low-frequency microstrip feed line and the high-frequency microstrip feed line, respectively. Under the combined action of the low-frequency radiator and the high-frequency radiator, a dual-frequency circularly polarized common-aperture patch antenna is formed.

[0039] In this process, the two equilateral L-shaped slots etched on the low-frequency antenna serve a triple purpose: firstly, they suppress the high-frequency induced current generated on the low-frequency antenna, thereby reducing problems such as pattern splitting, deflection, and low polarization purity during high-frequency antenna element radiation; secondly, they suppress the low-frequency induced current generated on the high-frequency antenna, thereby reducing problems such as pattern deflection and low gain during low-frequency antenna element radiation; thirdly, the outer equilateral L-shaped slot can also adjust the impedance matching of the low-frequency antenna itself, and the two slot stubs loaded on the inner and outer equilateral L-shaped slots can work together to adjust the disturbance to the low-frequency antenna's operating mode, achieving the circular polarization performance of the low-frequency antenna. Simultaneously, the curvature of the low-frequency antenna's circular edge can adjust the radiation deflection angle of the high-frequency antenna. Isolation between the high-frequency and low-frequency ports is mainly achieved through open-circuit stubs loaded on each port.

[0040] Figure 5This demonstrates the average current distribution of the circularly polarized common-aperture patch antenna before and after decoupling, when only the low-frequency antenna is excited. Figure 5 As shown in (a), when only low-frequency is excited, a strong induced current also exists on the high-frequency element. This induced current will cause secondary radiation, affecting the normal radiation of the low-frequency antenna. And from... Figure 5 As can be seen from (b), after decoupling, the low-frequency induced current on the high-frequency unit is significantly reduced, so the low-frequency antenna returns to its normal radiation state.

[0041] Figure 6 The average current distribution of the circularly polarized common-aperture patch antenna before and after decoupling, when only the high-frequency element is excited, is shown. It can be seen that after decoupling, when only the high-frequency element is excited, the high-frequency induced current on the low-frequency antenna is significantly reduced compared to before decoupling, and the high-frequency element can maintain normal radiation. Therefore, by reducing the coupling between the high-frequency and low-frequency antennas in a finely spaced high-frequency patch array, dual decoupling of the high-frequency and low-frequency ports and radiation patterns is achieved, resulting in a dual-frequency circularly polarized common-aperture patch antenna with a low profile and small size.

[0042] In this embodiment, an RO4003C dielectric substrate is used, and the overall antenna size is 1.1. l L × 1.1 l L ×0.06 l L . Figure 7 The simulation results before and after decoupling of the circularly polarized common-aperture patch antenna in this embodiment are shown. S Parameter comparison. From Figure 7 As shown in (a), before decoupling, the low-frequency antenna was mismatched, and the -10 dB impedance matching bandwidth of the high-frequency unit was 7%, corresponding to bandwidths of 4.81 GHz - 4.94 GHz and 5.17 GHz - 5.4 GHz. After decoupling, the -10 dB impedance matching bandwidth of the low-frequency antenna covered 3.37 GHz to 4.03 GHz, with a relative bandwidth of 18.9%, while the -10 dB impedance matching bandwidth of the high-frequency unit covered 4.81 GHz to 5.25 GHz, with a relative bandwidth of 9.2%. This indicates that the matching of both the low-frequency antenna and the high-frequency unit was improved after decoupling, enabling smooth signal feeding over a wider frequency range. Furthermore, before decoupling, the mutual coupling level between the low-frequency and high-frequency ports was -7 dB, while after decoupling, the mutual coupling level was below -17 dB, thus effectively improving the isolation between the low-frequency and high-frequency ports.

[0043] Figure 8The simulation comparison of the axial ratio of the circularly polarized common-aperture patch antenna in this embodiment before and after decoupling is shown. Before decoupling, the axial ratio of the low-frequency antenna is much greater than 3dB. After decoupling, the 3dB axial ratio frequency band of the low-frequency antenna covers 3.45 GHz to 3.54 GHz with a relative bandwidth of 2.6%. The 3dB axial ratio frequency band of the high-frequency element covers 4.81 GHz to 4.91 GHz with a relative bandwidth of 2.0%. It can be seen that a circularly polarized low-frequency antenna and a high-frequency element can be obtained after decoupling.

[0044] Figure 9 This paper presents a comparison of simulated radiation patterns before and after decoupling when only the low-frequency antenna is excited by the circularly polarized common-aperture patch antenna in this embodiment. Figure 9 It can be seen that before decoupling, the main polarization gain of the low-frequency antenna in the phi=0° and phi=90° planes is -0.19 dBic and -1.95 dBic, respectively, and the cross-polarization levels are -0.79 dB and -1.3 dB, respectively. After decoupling, the main polarization gain of the low-frequency antenna in the phi=0° and phi=90° planes is increased to 8.8 dBic, and the cross-polarization is increased to 16.8 dB and 13.8 dB, respectively. It can be seen that the radiation of the low-frequency antenna is improved after decoupling.

[0045] Figure 10 This paper presents a comparison of simulated radiation patterns before and after decoupling when only the high-frequency element of the circularly polarized common-aperture patch antenna in this embodiment is excited. Figure 10 It can be seen that before decoupling, the main polarization gain of the high-frequency antenna in the phi=0° and phi=90° planes is 2.3 dBic and -1.63 dBic, respectively, and the cross-polarization levels are 2.38 dB and -6.2 dB, respectively; after decoupling, the main polarization gain of the low-frequency antenna in the phi=0° and phi=90° planes is 7.0 dBic and 7.6 dBic, respectively, and the cross-polarization levels are 6 dB and 12.3 dB, respectively. It can be seen that the radiation of the high-frequency element is also improved after decoupling.

[0046] This invention realizes a circularly polarized common-aperture patch antenna with low profile, small size and low mutual coupling between high and low frequency elements under the condition of high-frequency sequential rotation-fed circularly polarized patch array with small spacing.

[0047] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A circularly polarized common-aperture patch antenna, characterized in that, The antenna includes a low-frequency radiator, a high-frequency radiator, a low-frequency microstrip feed line, and a high-frequency microstrip feed line. The low-frequency radiator includes a slot-loaded rhomboid metal patch. The high-frequency radiator includes a rotating array of diagonally cut square metal patches with oblique slots. The low-frequency radiator is positioned above the high-frequency radiator. A low-frequency signal is fed into the low-frequency radiator from the low-frequency microstrip feed line, and a high-frequency sequentially rotating signal is fed into the high-frequency radiator from the high-frequency microstrip feed line. Under the combined action of the low-frequency radiator and the high-frequency radiator, a dual-frequency circularly polarized common-aperture patch antenna is formed. The circularly polarized common-aperture patch antenna includes, from top to bottom, a first metal layer (1), a top dielectric substrate (2), a second metal layer (3), an intermediate dielectric substrate (4), a metal ground (5), a bottom dielectric substrate (6), a bottom metal layer (7), and a metal probe group; the first metal layer (1) is located on the upper surface of the top dielectric substrate (2), the second metal layer (3) is located on the upper surface of the intermediate dielectric substrate (4), the metal ground (5) is located on the upper surface of the bottom dielectric substrate (6), and the bottom metal layer (7) is located on the lower surface of the bottom dielectric substrate (6); air layers are respectively provided between the top dielectric substrate (2) and the second metal layer (3), and between the second metal layer (3) and the metal ground (5); The first metal layer (1) is a diamond-shaped metal patch (101) loaded with a groove. The groove includes an outer equilateral L-shaped groove (102), a horizontal groove branch (103), a vertical groove branch (104), and an inner equilateral L-shaped groove (105). The inner equilateral L-shaped groove (105) is parallel to the outer equilateral L-shaped groove (102), and the inflection points of the outer equilateral L-shaped groove (102) and the inner equilateral L-shaped groove (105) are both located at the upper right of the diamond-shaped metal patch (101). The horizontal groove branch (103) is located on the vertical groove side of the outer equilateral L-shaped groove (102), and the vertical groove branch (104) is located on the horizontal groove side of the outer equilateral L-shaped groove (102).

2. The circularly polarized common-aperture patch antenna according to claim 1, characterized in that, The second metal layer (3) includes four diagonally chamfered square metal patches (301) with slanted grooves (302), the chamfers being located at both ends of the slanted grooves; the four diagonally chamfered square metal patches (301) are distributed in a rotating manner.

3. The circularly polarized common-aperture patch antenna according to claim 2, characterized in that, The bottom metal (7) includes four stepped metal strips (701) arranged in a rotating pattern and one horizontal stepped metal strip (702); the first branch (703) is vertically loaded on the four stepped metal strips (701) respectively, and the second branch (704) is vertically loaded on the horizontal stepped metal strip (702). The rhomboid metal patch (101) and the horizontal stepped metal strip (702) are connected by a first metal probe (801), with the connection point located on the vertical center line of the rhomboid metal patch (101); the diagonally chamfered square metal patch (301) and the stepped metal strip (701) are respectively connected one-to-one by four second metal probes (802), with the connection point located on the horizontal or vertical center line of the four diagonally chamfered square metal patches (301).

4. The circularly polarized common-aperture patch antenna according to claim 3, characterized in that, The four sides of the rhomboid metal patch (101) are curved, with an arc length of 0.

29. λ L -0.3 λ L between, λ L This is the free-space wavelength corresponding to the operating frequency of the low-frequency antenna.

5. The circularly polarized common-aperture patch antenna according to claim 4, characterized in that, The side length of the outer equilateral L-shaped groove (102) is 0.

11. λ L -0.12 λ L Between, the length of the horizontal trough branch (103) is 0.

07. λ L -0.08 λ L Between, the length of the vertical groove branch (104) is 0.03 λ L -0.04 λ L Between them, the side length of the inner equilateral L-shaped groove (105) is 0.

12. λ L -0.13 λ L between.

6. The circularly polarized common-aperture patch antenna according to claim 5, characterized in that, The center-to-center spacing between adjacent diagonally cut square metal patches (301) is 0.

5. λ H , λ H The free-space wavelength corresponds to the operating frequency of the high-frequency unit.

7. The circularly polarized common-aperture patch antenna according to claim 6, characterized in that, The length of the first branch (703) is 0.

14. λ L -0.15 λ L Between, the length of the second branch (704) is 0.

13. λ H -0.14 λ H between.

Images