阅读说明：本技术 一种小型化三频段微带天线 (Miniaturized three-frequency-band microstrip antenna ) 是由 吴琦 张栋梁 于 2021-07-01 设计创作，主要内容包括：一种小型化三频段微带天线包括：金属地；下层介质基板,其被设置在金属地上；下层贴片,其被设置在下层介质基板上,在该下层贴片上形成有切角；上层介质基板,其被设置在下层贴片上；上层贴片,其被设置在上层介质基板上,在该上层贴片上形成有切角；同轴探针,其被设置成穿过所述下层介质基板、下层贴片和上层介质基板并与上层贴片接合；和短路探针,其被设置成穿过所述下层介质基板和上层介质基板并与所述上层贴片连接。(A miniaturized tri-band microstrip antenna comprising: a metal ground; a lower dielectric substrate disposed on the metal ground; a lower layer patch which is arranged on the lower layer medium substrate and is provided with a chamfer; an upper dielectric substrate disposed on the lower patch; an upper layer patch, which is arranged on the upper layer medium substrate and is provided with a chamfer; a coaxial probe disposed through the lower dielectric substrate, the lower patch and the upper dielectric substrate and bonded to the upper patch; and a short-circuit probe which is arranged to penetrate through the lower dielectric substrate and the upper dielectric substrate and is connected with the upper patch.)

1. A miniaturized tri-band microstrip antenna, comprising:

a metal ground;

a lower dielectric substrate disposed on the metal ground;

a lower layer patch which is arranged on the lower layer medium substrate and is provided with a chamfer;

an upper dielectric substrate disposed on the lower patch;

an upper layer patch, which is arranged on the upper layer medium substrate and is provided with a chamfer;

a coaxial probe arranged to pass through the lower dielectric substrate, the lower patch and the upper dielectric substrate and to be bonded to the upper patch for feeding the upper patch; and

and the short-circuit probe is arranged to penetrate through the lower dielectric substrate and the upper dielectric substrate and is connected with the upper patch.

2. The miniaturized triple-band microstrip antenna of claim 1 wherein the metal ground, lower dielectric substrate, lower patch, upper dielectric substrate and upper patch are substantially square shaped and stacked with substantial center overlap.

3. The miniaturized tri-band microstrip antenna of claim 1,

the corner cuts of the upper layer patches are formed symmetrically in a diagonal direction.

4. The miniaturized tri-band microstrip antenna of claim 3 wherein,

the upper layer patch comprises diagonal stubs symmetrically arranged in the other diagonal direction in a direction different from the cutting angle, and the diagonal stubs are used for being connected with the short-circuit probes.

5. The miniaturized tri-band microstrip antenna of claim 3 wherein,

the upper patch comprises peripheral short stubs arranged on the periphery of the upper patch, and the length of the peripheral short stubs is shorter than the side length of the upper patch.

6. The miniaturized tri-band microstrip antenna of claim 3 wherein,

the corner cut of the lower layer patch is formed symmetrically in a diagonal direction, and the corner cut of the lower layer patch is formed in a different orientation from the corner cut of the upper layer patch.

7. The miniaturized tri-band microstrip antenna of claim 6,

the lower patch includes a rectangular opening formed in a substantially central location.

8. The miniaturized tri-band microstrip antenna of claim 6,

the lower layer patch includes an L-shaped slot formed in a diagonal corner oriented differently from the cut corner thereon.

9. The miniaturized tri-band microstrip antenna of claim 1,

the coaxial probe is disposed at a position offset from the center of the upper patch.

Technical Field

The invention belongs to the field of microwave devices, and relates to a miniaturized tri-band microstrip antenna, in particular to a miniaturized tri-band microstrip antenna working in two circularly polarized frequency bands and an omnidirectional radiation polarized frequency band.

Background

The continuous development of wireless communication technology puts higher demands on the antenna as the radio frequency front end. The antenna is more emphasized in the aspects of miniaturization, broadband (including multiple frequency bands), integration and the like, and due to the practical situation requirements such as space limitation, the antennas need to be placed together for operation in many applications, so that coupling between the antennas becomes an important factor influencing the performance of the antennas, and therefore, it is necessary to design a composite antenna with good characteristics, which can work in multiple frequency bands.

The circularly polarized antenna has the advantages of radiation or reception of any polarized wave, strong anti-interference capability, polarization isolation of electromagnetic waves with different rotation directions and larger numerical values, and the like, and is widely applied to systems such as communication, radar, positioning, electronic countermeasure and the like. The omnidirectional linear polarization antenna with the omnidirectional radiation characteristic is widely applied to mobile communication because incoming waves can be in any directions.

Therefore, there is a strong need in the art for a composite antenna that can operate in multiple frequency bands with good characteristics and can simultaneously meet the requirements of different applications.

Disclosure of Invention

In order to overcome the disadvantages of the prior art, the present invention provides a miniaturized triple-band microstrip antenna which integrates a circularly polarized antenna and an omnidirectional linear polarized antenna, can meet the requirement of rf system integration, reduce the number of antennas on a platform, solve the problem of severe coupling of antennas in a limited space, and relieve the layout pressure of antennas on modern advanced platforms.

In order to achieve the above object, according to an embodiment of the present invention, there is provided a miniaturized triple-band microstrip antenna including: a metal ground; a lower dielectric substrate disposed on the metal ground; a lower layer patch which is arranged on the lower layer medium substrate and is provided with a chamfer; an upper dielectric substrate disposed on the lower patch; an upper layer patch, which is arranged on the upper layer medium substrate and is provided with a chamfer; a coaxial probe arranged to pass through the lower dielectric substrate, the lower patch and the upper dielectric substrate and to be bonded to the upper patch for feeding the upper patch; and a short-circuit probe which is arranged to penetrate through the lower dielectric substrate and the upper dielectric substrate and is connected with the upper patch.

Alternatively, in another embodiment, the metal ground, the lower dielectric substrate, the lower patch, the upper dielectric substrate and the upper patch may be formed in a substantially square shape and stacked with substantially overlapping centers.

Alternatively, in another embodiment, the cut corners of the upper layer patch are symmetrically formed in a diagonal direction.

Alternatively, in another embodiment, the upper layer patch may include diagonal stubs symmetrically disposed in another diagonal direction different from the chamfer, the diagonal stubs being used to connect with the shorting probes.

Alternatively, in another embodiment, the upper layer patch may include a peripheral stub disposed at a circumference thereof, the length of which is shorter than a side length of the upper layer patch.

Alternatively, in another embodiment, the cut angle of the lower patch is formed symmetrically in a diagonal direction, and the cut angle of the lower patch is formed in a different orientation than the cut angle of the upper patch.

Optionally, in another embodiment, the lower layer patch includes a rectangular opening formed in a substantially central location.

Alternatively, in another embodiment, the underlying patch includes an L-shaped slot formed in a diagonal corner that is oriented differently than the corner cut thereon.

Optionally, in another embodiment, the coaxial probe is disposed at a position offset from the center of the upper patch.

In order to achieve the above object, according to another embodiment of the present invention, there is provided a miniaturized triple-band microstrip antenna, which includes three bands, i.e., two left-handed circularly polarized bands and one omni-directional radiation polarized band, and which adopts a basic form of a microstrip patch antenna, and implements a multi-band operation of the antenna by stacking two patches, performing corner cut processing on the patches and shifting feeding from a central point to implement circular polarization, wherein the upper patch is fed by a coaxial probe, the lower patch is electromagnetically coupled and excited by the upper patch, and the stub and the short probe are loaded on the upper patch to improve a circular polarization axial ratio and a roundness of an omni-directional radiation pattern of the antenna.

According to another embodiment of the present invention, a miniaturized tri-band microstrip antenna is provided, which has a basic form of a microstrip antenna, and realizes the required functions by using two layers of patches and the loading of the corner cut, the stub and the short-circuit probe of the patches. Optionally, the antenna structure may be divided into 5 layers from bottom to top, which are in turn: the antenna comprises a metal ground, a lower layer dielectric substrate, a lower layer patch, an upper layer dielectric substrate and an upper layer patch, wherein the antenna is fed by using a coaxial probe, the lower layer patch is provided with a corner cut design and a slot cut design, the upper layer patch is provided with a corner cut design and a stub loading design, and a stub formed on a diagonal line of the upper layer patch is connected with a short circuit through hole for accommodating a short circuit probe.

Preferably, a chamfer is formed on one diagonal of a lower patch of the miniaturized triple-band microstrip antenna to ensure circular polarization of the antenna, a slot is formed on the other diagonal of the lower patch, and an opening structure is formed in the center of the lower patch to improve impedance matching of the antenna. Optionally, the slot is an L-shaped slot. Optionally, the opening structure is a rectangular opening.

Preferably, one diagonal line of an upper patch of the miniaturized triple-band microstrip antenna is provided with a corner cutting structure to ensure circular polarization of the antenna, peripheral short stubs are loaded on the periphery of the upper patch and can be used for adjusting the circular polarization and linear polarization working band of the antenna, and a diagonal short stub is arranged on the other diagonal line of the upper patch and is used for connecting a short-circuit probe in a short-circuit through hole to improve the omnidirectional radiation characteristic of the linear polarization working band.

Preferably, the upper patch of the antenna is fed by a coaxial probe, and the lower patch is excited by electromagnetic coupling of the upper patch.

Preferably, the sizes of the upper patch and the lower patch of the antenna decrease with the increase of the working frequency band of the antenna, and the feeding position of the antenna changes with the change of the working frequency of the antenna.

Preferably, the metal ground, the upper patch and the lower patch of the antenna are made of copper material with the thickness of 0.2-0.8mm through printing. Optionally, the dielectric constants ∈ of the upper dielectric substrate and the lower dielectric substrate range from 1 to 100.

Compared with the prior art, the miniaturized triple-band microstrip antenna provided by the embodiment of the invention has the following advantages: the device comprises two circularly polarized frequency bands and an omnidirectional linearly polarized frequency band; three antennas which independently work in three different frequency bands and have left-hand circular polarization and omnidirectional linear polarization are integrated into one antenna, so that the number of the antennas is reduced, and the space required by antenna layout is reduced; one diagonal line of the patch on the uppermost layer is connected with a short-circuit probe in the short-circuit through hole through a diagonal stub to be grounded, so that the omnidirectional radiation characteristic of a linear polarization working frequency band is improved, and the linear polarization working frequency band is independently adjustable relative to a circularly polarized working frequency band; the upper layer patch is excited by feeding through the coaxial probe, and the lower layer patch is excited by electromagnetic coupling of the upper layer patch, so that the structure is further simplified, and the size is reduced.

Other apparatuses, devices, systems, methods, features, and advantages of the invention will be or become apparent with reference to the following description and drawings. It is intended that all such additional systems, methods, features and advantages be included within this description, be within the scope of the invention, and be protected by the accompanying claims.

Drawings

The invention may be better understood by reference to the following drawings. The components in the figures are not to be considered as drawn to scale, emphasis instead being placed upon illustrating the principles of the invention.

Fig. 1 is a top view of a miniaturized triple-band microstrip antenna according to an embodiment of the present invention;

fig. 2 is a side cross-sectional view of a miniaturized triple-band microstrip antenna according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of an upper patch of a miniaturized triple-band microstrip antenna according to an embodiment of the present invention;

fig. 4 is a schematic structural diagram of a lower patch of a miniaturized triple-band microstrip antenna according to an embodiment of the present invention;

fig. 5 is a return loss of a first circularly polarized operating band of a first example of a miniaturized triple-band microstrip antenna to which an embodiment of the present invention is applied;

fig. 6 is an axial ratio of a first circularly polarized operating band of a first example of a miniaturized triple-band microstrip antenna to which an embodiment of the present invention is applied;

fig. 7 is a return loss of a second circularly polarized operating band of a first example of a miniaturized triple-band microstrip antenna according to an embodiment of the present invention;

fig. 8 is an axial ratio of a second circularly polarized operating band of a first example of a miniaturized triple-band microstrip antenna according to an embodiment of the present invention;

fig. 9 is a return loss of an operating band of omnidirectional linear polarization radiation to which an embodiment of the miniaturized triple-band microstrip antenna according to an embodiment of the present invention is applied; and

fig. 10 is a directional diagram of an operating band of omnidirectional linear polarization radiation of a first embodiment of a miniaturized triple-band microstrip antenna according to an embodiment of the present invention.

Detailed Description

Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. It is to be noted that, unless otherwise specified, technical or scientific terms used herein shall have the ordinary meaning as understood by those skilled in the art to which the present invention belongs.

In order to achieve the above object, according to an embodiment of the present invention, there is provided a miniaturized triple-band microstrip antenna including: a metal ground; a lower dielectric substrate disposed on the metal ground; a lower layer patch which is arranged on the lower layer medium substrate and is provided with a chamfer; an upper dielectric substrate disposed on the lower patch; an upper layer patch, which is arranged on the upper layer medium substrate and is provided with a chamfer; a coaxial probe arranged to pass through the lower dielectric substrate, the lower patch and the upper dielectric substrate and to be bonded to the upper patch for feeding the upper patch; and a short-circuit probe which is arranged to penetrate through the lower dielectric substrate and the upper dielectric substrate and is connected with the upper patch.

Alternatively, in another embodiment, the metal ground, the lower dielectric substrate, the lower patch, the upper dielectric substrate and the upper patch may be formed in a substantially square shape and stacked with substantially overlapping centers.

Alternatively, in another embodiment, the cut corners of the upper layer patch are symmetrically formed in a diagonal direction.

Alternatively, in another embodiment, the upper layer patch may include diagonal stubs symmetrically disposed in another diagonal direction different from the chamfer, the diagonal stubs being used to connect with the shorting probes.

Alternatively, in another embodiment, the upper layer patch may include a peripheral stub disposed at a circumference thereof, the length of which is shorter than a side length of the upper layer patch.

Alternatively, in another embodiment, the cut angle of the lower patch is formed symmetrically in a diagonal direction, and the cut angle of the lower patch is formed in a different orientation than the cut angle of the upper patch.

Optionally, in another embodiment, the lower layer patch includes a rectangular opening formed in a substantially central location.

Alternatively, in another embodiment, the underlying patch includes an L-shaped slot formed in a diagonal corner that is oriented differently than the corner cut thereon.

Optionally, in another embodiment, the coaxial probe is disposed at a position offset from the center of the upper patch.

A miniaturized triple-band microstrip antenna according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. Fig. 1 is a top view of a miniaturized triple-band microstrip antenna according to an embodiment of the present invention. Fig. 2 is a side cross-sectional view of a miniaturized triple-band microstrip antenna according to an embodiment of the present invention. Fig. 3 is a schematic structural diagram of an upper patch of a miniaturized triple-band microstrip antenna according to an embodiment of the present invention. FIG. 4 is a schematic structural diagram of a lower patch of a miniaturized triple-band microstrip antenna according to an embodiment of the present invention

As shown in fig. 1 to 4, a miniaturized triple-band microstrip antenna 100 according to an embodiment of the present invention includes: a metal ground (not shown) located at the bottommost portion; a lower dielectric substrate 40 disposed on a metal ground; a lower layer patch 30 provided on a lower layer dielectric substrate 40, the lower layer patch 30 having a corner cut 32 formed thereon; an upper dielectric substrate 20 disposed on the lower patch 30; an upper layer patch 10 provided on an upper layer dielectric substrate 20, the upper layer patch 10 having a chamfer 12 formed thereon; a coaxial probe 50, which is arranged to penetrate the lower dielectric substrate 40, the lower patch 30 and the upper dielectric substrate 20 and is jointed with the upper patch 10, for feeding the upper patch 10; and a short-circuit probe 60 which is arranged to penetrate through the lower dielectric substrate 40 and the upper dielectric substrate 20 and is connected with the upper patch 10. The miniaturized tri-band microstrip antenna 100 adopts a microstrip patch antenna as a basic form, and multi-band operation of the antenna is realized by stacking two layers of patches including an upper layer patch 10 and a lower layer patch 30. As shown, the metal ground, the lower dielectric substrate 40, the lower patch 30, the upper dielectric substrate 20 and the upper patch 10 may be formed in a substantially square shape and stacked with substantially overlapping centers, thereby facilitating manufacturing and assembly and facilitating implementation of functions. Circular polarization is realized by performing a corner cutting process on the upper and lower patches 10 and 30. The upper layer patch 10 is fed by a coaxial probe 50. The coaxial probe 50 may also be disposed at a position offset from the center of the upper layer patch 10, thereby further facilitating the circular polarization function. The lower patch 30 is excited by electromagnetic coupling of the upper patch 10. The cut angles of the upper patch 10 and the lower patch 30 may be set in different orientations. As shown in fig. 2, the short-circuit probe 60 loaded on the upper patch 10 can improve the circular polarization axial ratio and the roundness of the omnidirectional radiation pattern of the antenna, and improve the omnidirectional radiation characteristic of the linear polarization operating band. In this example two shorting probes 60 are provided, the shorting probes 60 passing through the lower dielectric substrate 40 and the upper dielectric substrate 20 and being connected to the upper patch 10 outside the lower patch 30 (thereby avoiding contact with the lower patch 30). It should be understood that more or fewer shorting probes 60 may be provided as desired in other applications. In this example, the miniaturized triple-band microstrip antenna 100 includes an upper patch 10, an upper dielectric substrate 20, a lower patch 30, and a lower dielectric substrate 40 that gradually increase in size from top to bottom to facilitate manufacturing assembly. In other embodiments, the shape and size settings of the various elements may also be adjusted as desired. With the above arrangement, the miniaturized triple-band microstrip antenna provided by the embodiment of the invention is a miniaturized triple-band microstrip antenna including two circularly polarized bands and an omnidirectional linearly polarized band.

As shown in fig. 3, the upper patch 10 of the miniaturized triple-band microstrip antenna according to the embodiment of the present invention has a substantially square shape, and a cut corner 12 is formed on one diagonal line thereof to provide good circular polarization characteristics. The pair of chamfer angles 12 may be formed to have the same shape and size and to be symmetrical in position. As shown in fig. 3, a peripheral stub 14 may be disposed around the upper patch 10, and may be used to adjust the operating frequency bands of the circular polarization and linear polarization of the antenna. In addition, a pair of diagonal stubs 16 for connecting the upper layer chip 60 and the shorting probe 60 may be provided on another diagonal line in a different orientation from the corner cut 12. The diagonal stubs 16 are respectively connected with the short-circuit probes 60, and the upper patch 10 is connected with the short-circuit probes 60 to lower the upper patch 10 to the ground, so that the omnidirectional radiation characteristic of a linearly polarized frequency band is improved, and the linearly polarized working frequency band is independently adjustable. A shorting via (not shown) for passing the shorting probe 60 may be formed on the upper dielectric substrate 20 and the lower dielectric substrate 40. It is to be understood that in other embodiments, the number, size, shape, location, etc. of the chamfer 12, the peripheral stub 14, the diagonal stub 16, etc. may be adjusted accordingly as desired.

As shown in fig. 4, the lower patch 30 of the miniaturized triple-band microstrip antenna provided according to the embodiment of the present invention has a substantially square shape, and a pair of cut corners 32 are formed on one diagonal line thereof to provide a good circular polarization characteristic. The pair of chamfer angles 32 may be formed to have the same shape and size and symmetrical positions. It is understood that in other embodiments, the chamfer 32 and/or the chamfer 12 may be differently shaped and sized. As shown, the cut corners 32 of the lower layer patch 30 are formed on a diagonal that is oriented differently than the cut corners 12 of the upper layer patch 10. A pair of slots, which are L-shaped slots 34, are symmetrically formed on the other diagonal line of the lower patch 30 at a different orientation from the corner cut 32 for improving the impedance matching of the antenna. The pair of L-shaped grooves 34 may be formed to have the same size and shape. Further, each L-shaped groove 34 may be formed by two rectangular grooves having the same size. It should be understood that the slot may be formed in other shapes as desired. An opening 36 is formed in the middle of the lower patch 30 to improve the impedance matching of the antenna. In this embodiment, the opening 36 is formed as a rectangular opening 36, for example in the form of a rectangular slit, which may result in a simple structure, easy processing and good results in application. In other embodiments, the opening 36 may be formed in other suitable forms as desired. A hole 38 is formed at a position of the lower patch 30 corresponding to the coaxial probe 50 for passing through the coaxial probe 50 feeding power to the upper patch 10, and the lower patch 30 is excited by electromagnetic coupling of the upper patch 10. The aperture 38 may be formed in a shape that matches the coaxial probe 50, such as circular, oval, rectangular, and the like. It should be understood that in other embodiments, the number, size, shape, location, etc. of the cut corners 32, openings 36, and holes 38, etc. may be adjusted accordingly, as desired.

The size of the upper patch 10 and the lower patch 30 of the miniaturized tri-band microstrip antenna 100 can be reduced as the operating band of the antenna is increased. In addition, the feeding position of the miniaturized triple-band microstrip antenna 100 may vary as the operating frequency of the antenna varies. Alternatively, the metal ground, the upper patch 10, and the lower patch 30 of the antenna 100 may be printed with a copper material having a thickness of 0.2-0.8 mm. Alternatively, the dielectric constants ε of the upper dielectric substrate 20 and the lower dielectric substrate 40 may be in the range of 1-100.

The miniaturized tri-band microstrip antenna provided according to an embodiment of the present invention is described in detail below with reference to fig. 5-10 by way of a specific exemplary embodiment. Fig. 5 is a return loss of the first circularly polarized operating band of the first embodiment of the miniaturized triple-band microstrip antenna according to the embodiment of the present invention. Fig. 6 is an axial ratio of a first circularly polarized operating band of a first example of a miniaturized triple-band microstrip antenna to which an embodiment of the present invention is applied. Fig. 7 shows the return loss of the second circularly polarized operating band of the first embodiment of the miniaturized triple-band microstrip antenna according to the embodiment of the present invention. Fig. 8 is an axial ratio of a second circularly polarized operating band of the first embodiment of the miniaturized triple-band microstrip antenna according to the embodiment of the present invention. Fig. 9 shows the return loss of the operating band of omnidirectional linear polarization radiation in the first example of the miniaturized tri-band microstrip antenna according to the embodiment of the present invention. Fig. 10 is a directional diagram of an operating band of omnidirectional linear polarization radiation of a first embodiment of a miniaturized triple-band microstrip antenna according to an embodiment of the present invention.

Example 1:

first, corresponding specific size values and relative position parameter values are given to an exemplary embodiment of a miniaturized triple-band microstrip antenna according to an embodiment of the present invention, and a performance test is further performed on the miniaturized triple-band microstrip antenna. It should be understood that a person skilled in the art can adjust the operating frequency of the antenna to adapt to different application scenarios of the antenna by adjusting the sizes of the upper patch 10 and the lower patch 30 without greatly changing the antenna structure.

In the present embodiment, the size of each relevant parameter of the miniaturized tri-band microstrip antenna is exemplarily set as follows:

w_s＝43.2mmw_g＝56mmh₁＝1.4mmh₂＝4mmw_p1＝28.4mm

w₁＝0.8mml₁＝16mmw₂＝0.1mml₂＝51mmΔ₁＝3mm

d＝5.6mmw_p2＝34.2mmw₃＝0.8mml₃＝10.4mmw₄＝6mm

l₄＝0.8mmΔ₂＝0.72mm

see FIGS. 1-4, wherein w_gRepresents the side length of a square metal floor (not shown in the figure) arranged below the lower-layer medium 40, and the side length of the lower-layer medium substrate 40 which is also a square; w is a_sRepresents the side length of the square upper dielectric substrate 20; h is₁And h₂Represent the thickness of the upper dielectric substrate 20 and the lower dielectric substrate 40, respectively; w is a_p1Representing the side length of the square upper patch; l₁And w₁Respectively representing the length and width of the peripheral stub 14 loaded around the square upper patch; l₂And w₂Represents the length and width of the diagonal stub 16 connected to the shorting probe 60 on one diagonal line of the upper patch 10, respectively; delta₁The cathetus length of one diagonal upper chamfer 12 of the upper patch 10 representing a square, in this example the chamfer 12 is an isosceles right triangle; d represents the length of the position on the upper patch 10 for disposing the coaxial probe 50 from the closer edge of the upper patch 10; w is a_p2The side length of the lower patch 30 representing a square; l₃And w₃Respectively representing the length and width of a rectangular segment of the lower patch 30 having an L-shaped slot 34 formed in a diagonal line thereof; l₄And w₄Respectively representing the length and width of the centrally slotted rectangular opening 36 of the lower patch 30; delta₂Representing the length of the legs of a diagonal upper corner cut 32 of the lower patch 30, the cut 32 being an isosceles right triangle.

Referring to fig. 5-8, the return loss and axial ratio of the two circularly polarized frequency bands of the antenna of the present invention are plotted based on the above specific parameter values, and in the corresponding frequency bands, the standing wave of the antenna is less than-10 dB, and the axial ratio of the antenna is less than 3 dB. The return loss and the directional diagram of the linearly polarized frequency band of the final antenna in the first exemplary embodiment are shown in fig. 9 and 10, the antenna reflection coefficient is less than-10 dB, and the out-of-roundness of the far-field radiation directional diagram of the antenna is less than 3 dB. Referring to fig. 5-10, the antenna of the present invention can simultaneously operate in two circularly polarized frequency bands and one linearly polarized frequency band, and can maintain good axial ratio characteristics in the operated circularly polarized frequency band and have good omnidirectional radiation characteristics in the operated linearly polarized frequency band.

The above-described embodiments are merely preferred embodiments of the present invention, which is not intended to limit the present invention in any way. Those skilled in the art can make many changes, modifications, and equivalents to the embodiments of the invention without departing from the scope of the invention as set forth in the claims below. Therefore, equivalent variations made according to the idea of the present invention should be covered within the protection scope of the present invention without departing from the contents of the technical solution of the present invention.

It is to be understood that the foregoing is merely illustrative of some embodiments and that changes, modifications, additions and/or variations may be made without departing from the scope and spirit of the disclosed embodiments, which are intended to be illustrative and not limiting. Furthermore, the described embodiments are directed to embodiments presently contemplated to be the most practical and preferred, it being understood that the embodiments should not be limited to the disclosed embodiments, but on the contrary, are intended to cover various modifications and equivalent arrangements included within the spirit and scope of the embodiments. Moreover, the various embodiments described above can be used in conjunction with other embodiments, e.g., aspects of one embodiment can be combined with aspects of another embodiment to realize yet another embodiment. In addition, each individual feature or element of any given assembly may constitute additional embodiments.

The above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention, and they should be construed as being included in the following claims and description.