Single-layer broadband circularly-polarized filtering antenna with rotary feed structure and use method of single-layer broadband circularly-polarized filtering antenna

Abstract

The invention discloses a single-layer broadband circularly polarized filtering antenna based on a rotary feed structure and a use method, relates to the technical field of antenna design, and is used for solving the technical problems that an existing filtering antenna is narrow in bandwidth, difficult to integrate and the like. The filtering antenna comprises a single-layer dielectric substrate, a top-layer metal patch, a feed metal through hole, a bottom-layer metal bottom plate and an input coaxial structure, wherein the top metal patch is arranged on the upper surface of the single-layer dielectric substrate; the bottom-layer metal bottom plate is arranged on the lower surface of the single-layer dielectric substrate; the top layer metal patch is connected with an inner conductor of the input coaxial structure through a feed metal through hole penetrating through the single-layer dielectric substrate, and an outer conductor of the input coaxial structure is connected with the bottom layer metal bottom plate, so that the rotary feed structure can be improved on the single-layer dielectric substrate, and the parasitic metal patch is additionally arranged on the single-layer dielectric substrate; therefore, the filtering antenna has broadband and filtering radiation performance.

Description

Technical Field

[0001] The present application relates to the technical field of antenna design, and provides a single-layer broadband circularly polarized filtering antenna based on a rotating feeding structure and a method for using the antenna. Background Art

[0002] As we all know, antennas, as the "medium" for transmitting and receiving electromagnetic waves in wireless systems, are a crucial component in the exchange of information between communication systems and the outside world. Therefore, the performance of the antenna directly impacts the overall performance of the communication system. Typically, the communication system and antenna are connected via a filter. The filter is used to filter out interfering frequencies when receiving signals, while the antenna only provides electromagnetic wave reception. This forces the communication system to rely entirely on the filter's out-of-band performance to filter out interfering frequencies, reducing overall space utilization. Consequently, to conserve design space, filter antennas, which directly attach filtering structures to the antenna, have emerged.

[0003] Currently, existing filtering antennas have the following structures: 1. Adding a filtering structure to the feed balun. However, although this structure can achieve the antenna filtering effect, it produces fewer zero points, has a narrow effective bandwidth, and the filtering structure is still concentrated in the feed structure; 2. Loading a slot structure on the antenna. Although this structure can also achieve a filtering effect, and the antenna gain curve introduces a radiation zero point at the out-of-band low frequency and high frequency respectively, this design is limited to linear polarization design, so it is susceptible to interference and has high polarization matching requirements.

[0004] Therefore, how to design a filtering antenna that has broadband, low profile and easy integration has become an urgent problem to be solved. Summary of the Invention

[0005] The present application provides a single-layer broadband circularly polarized filtering antenna with a rotating feed structure and a method of use, which are used to solve technical problems such as narrow bandwidth and difficult integration of existing filtering antennas.

[0006] On the one hand, a single-layer broadband circularly polarized filter antenna based on a rotating feed structure is provided, wherein the filter antenna comprises a single-layer dielectric substrate, a top metal patch, a feed metal through hole, a bottom metal base plate, and an input coaxial structure; The top metal patch is arranged on the upper surface of the single-layer dielectric substrate; the bottom metal base plate is arranged on the lower surface of the single-layer dielectric substrate; the top metal patch is connected to the inner conductor of the input coaxial structure through a feed metal through-hole penetrating the single-layer dielectric substrate, and the outer conductor of the input coaxial structure is connected to the bottom metal base plate.

[0007] Optionally, the top metal patch includes a rotating feed metal patch, four radiating metal patches and four parasitic metal patches; The one rotating feeding metal patch is connected to the four radiating metal patches respectively; and the four radiating metal patches are inductively coupled to the four parasitic metal patches respectively.

[0008] Optionally, the rotary feeding metal patch has a plurality of annular folding lines inside and outside, and the rotation direction of the plurality of annular folding lines is consistent with the rotation direction of the rotary feeding metal patch.

[0009] Optionally, the radiation metal patch is a rectangular structure, a circular structure or a triangular structure.

[0010] Optionally, the parasitic metal patch is a straight line structure, an arc structure or a broken line structure.

[0011] Optionally, the feed metal through hole is connected to the rotary feed metal patch through a 0.6 mm circular pad.

[0012] Optionally, the input coaxial structure uses an SMA connector, an N-type connector or a K connector for coaxial connection. Optionally, the single-layer dielectric substrate uses a square Taconic RF-35 dielectric with a side length of 10 mm.

[0013] On the one hand, a method for using a single-layer broadband circularly polarized filter antenna based on a rotating feed structure is provided, the method comprising: An input coaxial structure is used to feed the RF signal into the feed metal through hole; The radio frequency signal is transmitted to the top metal patch by using the feed metal through hole; The top metal patch is used to transmit the radio frequency signal.

[0014] Optionally, the step of transmitting the radio frequency signal using the top metal patch includes: Using a rotating feeding metal patch to transmit the radio frequency signal to the radiating metal patch; The radiating metal patch is used to transmit the radio frequency signal to the parasitic metal patch through a coupled feeding method; The parasitic metal patch is used to transmit the radio frequency signal.

[0015] In one aspect, a storage medium is provided, on which computer program instructions are stored, and when the computer program instructions are executed by a processor, any of the above methods is implemented.

[0016] Compared with the prior art, the present invention has the following advantages: In this application, the filtering antenna includes a single-layer dielectric substrate, a top metal patch, a feed metal via, a bottom metal base plate, and an input coaxial structure. The top metal patch is disposed on the upper surface of the single-layer dielectric substrate; the bottom metal base plate is disposed on the lower surface of the single-layer dielectric substrate; the top metal patch is connected to the inner conductor of the input coaxial structure via a feed metal via penetrating the single-layer dielectric substrate; and the outer conductor of the input coaxial structure is connected to the bottom metal base plate. Furthermore, the top metal patch includes a rotating feed metal patch, four radiating metal patches, and four parasitic metal patches.

[0017] Based on this, in this application, since the filtering antenna adopts a single-layer dielectric substrate, compared with the existing multi-layer dielectric substrate structure, the filtering antenna of this application is easier to integrate and can effectively reduce the antenna profile. Moreover, since the rotating feed metal patch can generate multiple radiation zero points, the rotating feed metal patch of this application not only has a certain filtering effect in a limited space, but also can flexibly adjust the zero point position according to the required working bandwidth, thereby designing circularly polarized filtering antennas of different frequency bands; in addition, since the parasitic metal patch can add additional axial ratio zero points while introducing radiation zero points, this application can, to a certain extent, broaden the working bandwidth and improve the filtering effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the following briefly introduces the drawings required for use in the embodiments or related technical descriptions. Obviously, the drawings described below are only embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0019] Figure 1 A schematic diagram of a single-layer broadband circularly polarized filter antenna with a rotating feed structure provided in an embodiment of the present application; Figure 2 A top view of a single-layer broadband circularly polarized filter antenna with a rotating feed structure provided in an embodiment of the present application; Figure 3 A schematic flow chart of a method for using a filtering antenna according to an embodiment of the present application; Figure 4 A schematic diagram of the return loss of a filtering antenna provided in an embodiment of the present application; Figure 5 A schematic diagram of an axial ratio curve of a filtering antenna provided in an embodiment of the present application; Figure 6 A schematic diagram of a filter antenna gain curve provided in an embodiment of the present application; Figure 7The E-plane radiation pattern of the filtering antenna provided in an embodiment of the present application at 26 GHz; Figure 8 This is the H-plane radiation pattern of the filtering antenna provided in an embodiment of the present application at 26 GHz.

[0020] Markings in the figure: 1-single-layer dielectric substrate, 2-top metal patch, 3-feed metal through-hole, 4-bottom metal base plate, 5-input coaxial structure, 21-rotating feed metal patch, 22-radiating metal patch, 23-parasitic metal patch. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solutions and advantages of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application. In the absence of conflict, the embodiments in the present application and the features in the embodiments can be combined with each other in any way. In addition, although a logical order is shown in the flow chart, in some cases, the steps shown or described can be performed in an order different from that here.

[0022] As we all know, antennas, as the "medium" for transmitting and receiving electromagnetic waves in wireless systems, are a crucial component in the exchange of information between communication systems and the outside world. Therefore, the performance of the antenna directly impacts the overall performance of the communication system. Typically, the communication system and antenna are connected via a filter. The filter is used to filter out interfering frequencies when receiving signals, while the antenna only provides electromagnetic wave reception. This forces the communication system to rely entirely on the filter's out-of-band performance to filter out interfering frequencies, reducing overall space utilization. Consequently, to conserve design space, filter antennas, which directly attach filtering structures to the antenna, have emerged.

[0023] Currently, existing filtering antennas have the following structures: 1. Adding a filtering structure to the feed balun. However, although this structure can achieve the antenna filtering effect, it produces fewer zero points, has a narrow effective bandwidth, and the filtering structure is still concentrated in the feed structure; 2. Loading a slot structure on the antenna. Although this structure can also achieve a filtering effect, and the antenna gain curve introduces a radiation zero point at the out-of-band low frequency and high frequency respectively, this design is limited to linear polarization design, so it is susceptible to interference and has high polarization matching requirements.

[0024] Based on this, an embodiment of the present application provides a single-layer broadband circularly polarized filter antenna with a rotating feed structure. Specifically, the filter antenna includes a single-layer dielectric substrate, a top metal patch, a feed metal through-hole, a bottom metal base plate, and an input coaxial structure. The top metal patch is arranged on the upper surface of the single-layer dielectric substrate; the bottom metal base plate is arranged on the lower surface of the single-layer dielectric substrate; the top metal patch is connected to the inner conductor of the input coaxial structure through the feed metal through-hole penetrating the single-layer dielectric substrate, and the outer conductor of the input coaxial structure is connected to the bottom metal base plate. Furthermore, the top metal patch includes a rotating feed metal patch, four radiating metal patches, and four parasitic metal patches.

[0025] Based on this, in this application, since the filtering antenna adopts a single-layer dielectric substrate, compared with the existing multi-layer dielectric substrate structure, the filtering antenna of this application is easier to integrate and can effectively reduce the antenna profile. Moreover, since the rotating feed metal patch can generate multiple radiation zero points, the rotating feed metal patch of this application not only has a certain filtering effect in a limited space, but also can flexibly adjust the zero point position according to the required working bandwidth, thereby designing circularly polarized filtering antennas of different frequency bands; in addition, since the parasitic metal patch can add additional axial ratio zero points while introducing radiation zero points, this application can, to a certain extent, broaden the working bandwidth and improve the filtering effect.

[0026] After introducing the design concepts of the embodiments of the present application, the following briefly introduces the application scenarios to which the technical solutions of the embodiments of the present application can be applied. It should be noted that the application scenarios introduced below are only used to illustrate the embodiments of the present application and are not limiting. In the specific implementation process, the technical solutions provided by the embodiments of the present application can be flexibly applied according to actual needs.

[0027] like Figure 1 The figure shows a schematic diagram of a single-layer broadband circularly polarized filter antenna with a rotating feed structure provided in an embodiment of the present application. It can be seen that the filter antenna includes a single-layer dielectric substrate 1, a top metal patch 2, a feed metal through-hole 3, a bottom metal base plate 4, and an input coaxial structure 5; wherein, the top metal patch 2 is arranged on the upper surface of the single-layer dielectric substrate 1; the bottom metal base plate 4 is arranged on the lower surface of the single-layer dielectric substrate 1; the top metal patch 2 is connected to the inner conductor of the input coaxial structure 5 through the feed metal through-hole 3 penetrating the single-layer dielectric substrate 1, and the outer conductor of the input coaxial structure 5 is connected to the bottom metal base plate 4. In addition, the bottom metal base plate 4 includes a circular hole with a diameter of 0.69 mm, and the center position of the circular hole is the same as that of the feed metal through-hole 3.

[0028] like Figure 2As shown, a top view of a single-layer broadband circularly polarized filter antenna with a rotating feeding structure provided in an embodiment of the present application shows that the top metal patch 2 includes a rotating feeding metal patch 21, four radiating metal patches 22 and four parasitic metal patches 23; wherein, a rotating feeding metal patch 21 is connected to the four radiating metal patches 22 through four connecting lines with a line width of 0.2 mm; the four radiating metal patches 22 are inductively coupled with the four parasitic metal patches 23, and are 0.225 mm apart.

[0029] In one possible implementation, Figure 2 As shown, the rotary feed metal patch 21 has several annular fold lines inside and outside, and the rotation direction of the annular fold lines is consistent with the rotation direction of the rotary feed metal patch 21. The inner ring of the rotary feed metal patch 21 is a two-thirds circle with a radius of 0.3mm and a line width of 0.1mm; the outer ring of the rotary feed metal patch 21 is a three-quarter circle with a radius of 1mm and a line width that changes stepwise from 0.7mm to 0.2mm.

[0030] Furthermore, compared to the traditional annular quarter-wavelength phase-shifted network in which spatial multiplexing is still possible, the filtering antenna of the present application can improve the space utilization of the feeding network and provide better filtering performance by nesting annular filtering branches inside and outside the annular network. Among them, the nested branches of the rotating feeding metal patch on the outer ring can introduce a radiation zero point at low frequency, at which the electromagnetic wave flows into the outer ring branch and is then reflected to the input port without being radiated through the radiating metal patch. In addition, the nested branches of the rotating feeding metal patch on the inner ring rotate along different rotation directions and have different lengths to introduce two radiation zero points at high frequencies. The nested branches of the inner ring are the same as the nested branches of the outer ring, and the nested branches of the inner ring are also radiation zero points formed by the reflection of the electromagnetic wave to the input port.

[0031] In a possible embodiment, the radiation metal patch 22 is a rectangular structure, a circular structure or a triangular structure. Figure 2 As shown, the radiating metal patch 22 can be a rectangular structure with a length of 2.5 mm and a width of 2.3 mm. A rectangular 45° groove can be cut inside the radiating metal patch 22, with a length of 0.4 mm and a width of 0.2 mm; and the cutting angle of the radiating metal patch 22 is 0.5 mm.

[0032] In a possible embodiment, the parasitic metal patch 23 is a straight line structure, an arc structure or a broken line structure. Figure 2 As shown, the parasitic metal patch 23 includes a 90° fold line with a line width of 0.25 mm and a 90° fold line with a line width of 0.15 mm. The two fold lines are connected by a connecting line with a width of 0.15 mm.

[0033] Furthermore, compared to the prior art, the present application introduces a parasitic metal patch with a multi-segment folded-line structure outside the radiating metal patch, and increases the radiation pole within the operating frequency band by regulating the coupling amount and resonant length of the folded-line structure. Moreover, since there is a pair of reverse currents between the radiating metal patch and the parasitic metal patch outside the radiation pole, the radiation field vectors cancel each other out, forming a radiation zero point. Therefore, the present filtering antenna can introduce a radiation zero point through impedance filtering and radiation cancellation, respectively, and the parasitic metal patch structure of the antenna introduces a new effective radiation mode. Therefore, the present application can achieve broadband radiation performance while ensuring the filtering effect of the antenna gain curve.

[0034] In a possible implementation, the feed metal via 3 is connected to the rotary feed metal patch 21 via a 0.6 mm circular pad.

[0035] In a possible embodiment, the input coaxial structure 5 uses an SMA connector, an N-type connector, or a K-type connector for coaxial connection. Of course, the connector selection in this application is not fixed, and the specific type of connector used can be determined by the actual design.

[0036] In a possible implementation, the single-layer dielectric substrate 1 uses a square Taconic RF-35 dielectric with a side length of 10 mm.

[0037] Based on the same inventive concept, the present application also provides a method for using a single-layer broadband circularly polarized filtering antenna based on a rotating feeding structure, such as Figure 3 FIG. 1 is a flow chart of a method for using a filtering antenna according to an embodiment of the present application, wherein the method can be performed by Figure 1 The method is performed by using a single-layer broadband circularly polarized filtering antenna based on a rotating feeding structure. Specifically, the process of the method is described as follows.

[0038] Step 301: Feeding a radio frequency signal into a feed metal through hole using an input coaxial structure.

[0039] Step 302: Use a feed metal via to transmit the radio frequency signal to the top metal patch.

[0040] Step 303: Use the top metal patch to transmit the radio frequency signal.

[0041] like Figure 2 As shown, after the rotating feeding metal patch of the top metal patch receives the RF signal, the rotating feeding metal patch can be used to transmit the RF signal to the radiating metal patch; then, the radiating metal patch can be used to transmit the RF signal to the parasitic metal patch through coupling feeding; finally, the parasitic metal patch can be used to transmit the RF signal.

[0042] In order to enable readers to have a clearer understanding of the present technical solution, the following is a detailed introduction to the filtering antenna of the present application in terms of "return loss, axial ratio curve, gain curve, E-plane antenna radiation characteristics and H-plane antenna radiation characteristics".

[0043] Specifically, such as Figure 4 As shown, it is a schematic diagram of the return loss of the filtering antenna provided in an embodiment of the present application. In the embodiment of the present application, the scattering parameter (Scattering Parameter) is based on -10dB. It can be seen that the working range of the antenna of the present application is 22.46GHz-29.66GHz, and the impedance bandwidth percentage is approximately 27.65%.

[0044] like Figure 5 As shown, it is a schematic diagram of the axial ratio curve of the filtering antenna provided in the embodiment of the present application. In the embodiment of the present application, the axial ratio (Axial Rratio) is based on 3dB. It can be seen that the working range of the antenna of the present application is 22.30GHz-28.53GHz, and the axial ratio bandwidth is about 24.51%.

[0045] like Figure 6 As shown, a schematic diagram of the filter antenna gain curve provided in an embodiment of the present application is provided. In the embodiment of the present application, the real gain (RHCP) of right-hand circular polarization is based on 5.7 dB. It can be seen that the antenna operating range of the present application is 22.10 GHz-29.88 GHz, and the gain bandwidth is approximately 29.93%.

[0046] like Figure 7 As shown, it is the E-plane radiation pattern of the filtering antenna provided by the embodiment of the present application at 26 GHz. It can be seen that the filtering antenna of the present application is a right-hand circularly polarized (RHCP) antenna.

[0047] like Figure 8 As shown, it is the H-plane radiation pattern of the filtering antenna provided by the embodiment of the present application at 26 GHz. It can be seen that the filtering antenna of the present application is a right-hand circularly polarized (RHCP) antenna.

[0048] In summary, this application has the following advantages: (1) Since the filtering antenna of the present application is designed with a single-layer dielectric substrate, the filtering antenna of the present application is easier to integrate than a multi-layer dielectric substrate structure and can effectively reduce the antenna profile.

[0049] (2) Since the rotating feed metal patch designed in this application can generate multiple radiation zero points, it can not only make the rotating feed metal patch have a certain filtering effect in a limited space, but also can flexibly adjust the zero point position according to the required working bandwidth, which is very suitable for designing circularly polarized filtering antennas of different frequency bands.

[0050] (3) The parasitic metal patch designed in this application is a multi-segment broken line structure. Therefore, while introducing the radiation zero point, it can also add an additional axis ratio zero point. Therefore, it is not only suitable for broadband design, but also has a better filtering effect and can be widely used in various communication equipment.

[0051] In some possible implementations, various aspects of the method provided in the present application may also be implemented in the form of a program component, which includes program code. When the program component is run on a computer device, the program code is used to enable the computer device to execute the steps of the method according to various exemplary embodiments of the present application described above in this specification. For example, the computer device may execute the following steps: Figure 2 The method performed in the illustrated embodiment.

[0052] Those skilled in the art will understand that all or part of the steps of the above-described method embodiments can be implemented using hardware associated with program instructions. The aforementioned program can be stored in a computer-readable storage medium. When executed, the program performs the steps of the above-described method embodiments. The aforementioned storage medium includes various media capable of storing program code, such as a removable storage device, read-only memory (ROM), random access memory (RAM), a magnetic disk, or an optical disk. Alternatively, if the integrated unit of the present invention is implemented as a software functional module and sold or used as a standalone component, it can also be stored in a computer-readable storage medium. Based on this understanding, the technical solutions of the embodiments of the present invention, or the portion that contributes to the prior art, can be embodied in the form of a software component. This computer software component, stored in a storage medium, includes instructions for enabling a computer device (such as a personal computer, server, or network device) to perform all or part of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as a removable storage device, ROM, RAM, a magnetic disk, or an optical disk.

[0053] Although the preferred embodiments of the present application have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present application.

[0054] Obviously, those skilled in the art may make various changes and modifications to this application without departing from the spirit and scope of this application. Thus, if these modifications and variations of this application fall within the scope of the claims of this application and their equivalents, this application is intended to include these modifications and variations.

Claims

1. A single-layer broadband circularly polarized filter antenna with a rotating feed structure, characterized in that: The filtering antenna comprises a single-layer dielectric substrate, a top metal patch, a feed metal through-hole, a bottom metal base plate and an input coaxial structure; The top metal patch is arranged on the upper surface of the single-layer dielectric substrate; the bottom metal base plate is arranged on the lower surface of the single-layer dielectric substrate; the top metal patch is connected to the inner conductor of the input coaxial structure through a feed metal through-hole penetrating the single-layer dielectric substrate, and the outer conductor of the input coaxial structure is connected to the bottom metal base plate.

2. The filtering antenna according to claim 1, wherein The top metal patch includes a rotating feed metal patch, four radiating metal patches and four parasitic metal patches; The one rotating feeding metal patch is connected to the four radiating metal patches respectively; and the four radiating metal patches are inductively coupled to the four parasitic metal patches respectively.

3. The filtering antenna according to claim 2, wherein: The rotating feeding metal patch has a plurality of annular folding lines inside and outside, and the rotation direction of the plurality of annular folding lines is consistent with the rotation direction of the rotating feeding metal patch.

4. The filtering antenna according to claim 2, wherein: The radiation metal patch is a rectangular structure, a circular structure or a triangular structure.

5. The filtering antenna according to claim 2, wherein: The parasitic metal patch is a straight line structure, an arc structure or a broken line structure.

6. The filtering antenna according to claim 2, wherein: The feed metal through hole is connected to the rotary feed metal patch through a 0.6 mm circular pad.

7. The filtering antenna according to claim 1, wherein: The input coaxial structure uses an SMA connector, an N-type connector or a K connector for coaxial connection.

8. The filtering antenna according to claim 1, wherein: The single-layer dielectric substrate is a square Taconic RF-35 dielectric with a side length of 10 mm.

9. A method for using a single-layer broadband circularly polarized filter antenna based on a rotating feed structure, characterized in that: A single-layer broadband circularly polarized filter antenna with a rotating feed structure according to any one of claims 1 to 8; the method comprising: An input coaxial structure is used to feed the RF signal into the feed metal through hole; The radio frequency signal is transmitted to the top metal patch by using the feed metal through hole; The top metal patch is used to transmit the radio frequency signal.

10. The method according to claim 9, wherein The step of transmitting the radio frequency signal using the top metal patch includes: Using a rotating feeding metal patch to transmit the radio frequency signal to the radiating metal patch; The radiating metal patch is used to transmit the radio frequency signal to the parasitic metal patch through a coupled feeding method; The parasitic metal patch is used to transmit the radio frequency signal.

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