WO2022104741A1

WO2022104741A1 - Dual-frequency feed source and dual-frequency antenna

Info

Publication number: WO2022104741A1
Application number: PCT/CN2020/130611
Authority: WO
Inventors: 邓如渊; 陈泽峰; 陈勇; 顾爱军
Original assignee: 华为技术有限公司
Priority date: 2020-11-20
Filing date: 2020-11-20
Publication date: 2022-05-27
Also published as: EP4231457A1; EP4231457A4

Abstract

The present application provides a dual-frequency feed source and a dual-frequency antenna, which can solve the problems of an existing dual-frequency antenna having a disordered electromagnetic field distribution, a high sidelobe and a deteriorated antenna pattern, and thus improve the performance of an antenna pattern. The dual-frequency antenna comprises a primary reflection surface, a secondary reflection surface, a dual-frequency feed source and a dielectric support, wherein the primary reflection surface and the secondary reflection surface are arranged opposite each other. The dual-frequency feed source comprises a low-frequency feed source and a high-frequency feed source. The dielectric support is arranged between the primary reflection surface and the secondary reflection surface, the dielectric support comprises an annular first support portion with an opening at one face, the opening of the first support portion is arranged facing the secondary reflection surface, and the thickness of the first support portion is related to a relative dielectric constant of the first support portion, an operating frequency of the low-frequency feed source and an operating frequency of the high-frequency feed source. The secondary reflection surface is fixedly connected to the opening position of the first support portion, and encloses a cavity with the first support portion; and a first end of the dual-frequency feed source passes through the first support portion and is located in the cavity, and a second end of the dual-frequency feed source is connected to the center of the primary reflection surface.

Description

A dual-frequency feed source and dual-frequency antenna

technical field

The present application relates to the field of wireless communication, and in particular, to a dual-frequency feed and a dual-frequency antenna.

Background technique

With the development of mobile broadband and fixed broadband networks, the backhaul capacity of base stations has doubled, and the challenges faced by microwave in the 5G era are increasing. Conventional microwave (6-42GHz) supports transmission distances up to 100km, has high reliability, and can meet the transmission requirements of macro stations, but the spectrum resources are increasingly tight and the transmission bandwidth is low (<1Gbps), making it increasingly difficult to expand. E-band (71-86GHz) microwave can support up to 20Gbps transmission capacity through Cross-Polarization Interference Cancellation (XPIC, Cross-Polarization Interference Cancellation) technology, meeting the capacity requirements of LTE/5G, but the transmission distance is generally less than 5km, which cannot meet the medium Backhaul requirements from the macro station. In order to solve the pain points of capacity and transmission distance, by integrating conventional microwave and E-band microwave, the long-distance and high reliability of conventional-band microwave links can be realized, and the large bandwidth characteristics of E-band microwave links can be realized.

In the prior art, the traditional dual-band antenna solution can adopt a frequency selective surface (Frequency Selective Surface, FSS) solution, as shown in FIG. 1 , the solution uses the FSS to physically isolate the signals of the two frequency bands. The existing dual-frequency antenna solution can also use a coaxial dual-frequency antenna to solve the above problems. As shown in Figure 2, this solution uses a coaxial dual-frequency feed source, and the dual-frequency feed source is composed of a low-frequency feed source and a high-frequency feed source. The two feeds share a main reflection surface and a sub-reflection surface, and the phase centers of the two feeds coincide with the focal point of the sub-reflection surface, thereby realizing the function of dual-frequency multiplexing. The traditional dual-band antenna solution can also use a multi-mode horn antenna as shown in Figure 3. This solution introduces high-order modes and reasonably allocates the mode ratio of high-order modes through structural discontinuities, such as steps or gradient structures. The feed can be made to work in two frequency bands at the same time, thereby realizing the dual-frequency multiplexing function.

In the coaxial dual feed scheme, the metal rod is mainly used as the support of the sub-reflector. This support method takes into account the problem of structural reliability, but pays less attention to the influence on the electrical performance of the antenna. The above support method is easy to increase the number of antennas and antennas. The interference between the two has the problems of disordered distribution of the electromagnetic field, high side lobes, and deterioration of the antenna pattern.

SUMMARY OF THE INVENTION

The embodiments of the present application provide a dual-frequency feed and a dual-frequency antenna, which can solve the problems of disordered electromagnetic field distribution, high side lobes, and deterioration of the antenna pattern of the existing coaxial dual-frequency antenna, and improve the pattern performance of the antenna. .

To achieve the above object, the application adopts the following technical solutions:

In a first aspect, a dual-frequency antenna is provided, including a main reflection surface, a sub-reflection surface, a dual-frequency feed source and a medium support, wherein the main reflection surface and the sub-reflection surface are arranged opposite to each other. The dual-frequency feed includes a low-frequency feed and a high-frequency feed. The center frequency of the operating frequency band of the low-frequency feed source is the first center frequency, and the center frequency of the operating frequency band of the high-frequency feed source is the second center frequency. The medium support is arranged between the main reflection surface and the sub-reflection surface. The medium support includes a ring-shaped first support portion with an opening on one side. The opening of the first support portion is arranged toward the sub-reflection surface. The relative permittivity of the part, the first center frequency, and the second center frequency are related. The secondary reflection surface is fixedly connected with the opening position of the first support part, and forms a cavity with the first support part; the first end of the dual-frequency feed source is arranged in the cavity through the first support part, and the second The two ends are connected at the center of the main reflecting surface.

On this basis, by setting the first support part of the radiation core region supported by the medium in a ring shape and made of a medium material, the medium material will not disturb the irradiation of the dual-frequency feed source, and the interference to the distribution of the electromagnetic field is small, and at the same time Electromagnetic transparency is achieved at high frequency feeds and low frequency feeds. The main body is a ring-shaped dielectric support, and the relative dielectric constant of the dielectric support, the first center frequency and the second center frequency are used to determine the thickness of the dielectric support, which is conducive to reducing side lobes and reducing the antenna received. interference to improve the antenna pattern and improve the electrical performance of the high and low frequency bands. By setting the medium support as a ring-shaped hollow support body, the structural reliability is high and the assembly is relatively convenient.

In a possible implementation manner of the first aspect, a cross section of the first support portion perpendicular to the extending direction of the dual-frequency feed source gradually increases along a first direction, where the first direction is the direction from the dual-frequency feed source to the sub-reflection surface direction of extension.

On this basis, by setting the first support part closer to the sub-reflecting surface, the cross section will be larger, so that the first support part changes in a horn shape, reducing the interference of the dielectric support on the transmission of electromagnetic waves, which is beneficial to improve the performance of the antenna pattern .

In a possible implementation manner of the first aspect, a cross-section of the first support portion perpendicular to the extending direction of the dual-frequency feed source is circular. On this basis, by setting the cross section of the first support portion perpendicular to the extension direction of the dual-frequency feed to a circular shape, the shape of the opening of the first support portion is closer to that of the sub-reflection surface, which facilitates fixing the sub-reflection surface. At the same time, the first support portion with the circular cross-section is also conducive to the transmission of electromagnetic waves and improves the characteristics of the antenna pattern.

In a possible implementation of the first aspect, the thickness of the dielectric support is related to the wavelength of the first half medium and the wavelength of the second half medium. Wherein, the first half medium wavelength is half of the medium wavelength of the first center frequency, and the second half medium wavelength is half of the medium wavelength of the second center frequency.

On this basis, by taking the first half medium wavelength and the second half medium wavelength as the reference standard for the thickness of the medium support, the determined thickness of the medium support can reduce the interference to the signal transmission of the antenna. The medium wavelength and the second half medium wavelength can take into account the radiation performance of high frequency and low frequency, and improve the performance of the antenna pattern.

In a possible implementation manner of the first aspect, the thickness of the dielectric support is 0.9-1.1N times the wavelength of the first half-medium, and 0.9-1.1M times the wavelength of the second half-medium. Among them, N and M are positive integers.

On this basis, the thickness value of the dielectric support is set to be close to the common multiple of the wavelength of the first half medium and the wavelength of the second half medium, so that the dielectric support can take into account the radiation performance of high frequency and low frequency, and the effect is the best, so that the high frequency and low-frequency electrical performance indicators as far as possible to achieve the best. A ±10% error is reserved for the thickness value of the dielectric support. The dielectric support whose thickness is within this error range has little effect on the electrical performance of the antenna, which improves the value range of the dielectric support, which can facilitate the antenna’s practical application. Production and processing.

In a possible implementation manner of the first aspect, the thickness of the medium support is X times the wavelength of the first half medium, and is 0.9 to 1.1M times the wavelength of the second half medium. Wherein, X≤0.25, M is a positive integer.

On this basis, when the frequency between the high frequency and the low frequency is relatively large, the thickness of the medium support is set to an integer multiple of the wavelength of the second half medium, and the error range of ±10% is reserved. At this time, the medium support The thickness of the medium is much smaller than the thickness of the wavelength of the first half medium, so a quarter of the wavelength length of the first half medium is selected as the threshold, so that the thickness of the medium support is not greater than this value, so that the radiation performance of high frequency and low frequency can be considered as much as possible. , so that the electrical properties of the two frequency bands meet the design requirements.

In a possible implementation manner of the first aspect, the thickness of the medium support is a positive integer multiple of the wavelength of the first half medium, and is a positive integer multiple of the wavelength of the second half medium. On this basis, by setting the thickness of the medium support to be a common multiple of the wavelength of the first half medium and the wavelength of the second half medium, the radiation performance of high frequency and low frequency can be taken into account, and the best effect can be achieved, reducing the impact of the medium support on the transmission of electromagnetic waves. interference and improve the performance of the antenna pattern.

In a possible implementation manner of the first aspect, the medium support includes a first support portion, and the shape of the first support portion is hemispherical. On this basis, since the dual-frequency feed radiates spherical waves during signal transmission, the signals are also sent and received in a spherical shape. The thickness of the hollow support body is a certain value, so its interior is also hemispherical, so that the transmission direction of the electromagnetic wave can be perpendicular to the inner surface of the first support part as much as possible when the electromagnetic wave is transmitted, thereby reducing the medium support. The effect of signal transmission is realized to improve the performance of the antenna pattern.

In a possible implementation manner of the first aspect, the medium support further includes a first connection part, a second support part and a second connection part, the first connection part, the second support part, the first support part and the second connection part The parts are connected in sequence, the first connection part is connected with the sub-reflection surface, and the second connection part is connected with the dual-frequency feed source.

On this basis, by arranging the medium support to be composed of multiple components, the specific shape of each component can be set according to the function and function of each component, wherein the first connection portion is used to realize the connection between the medium support and the sub-reflection surface. The second connection part is used to realize the connection between the medium support and the dual-frequency feed, and the second support can be used to adjust the position of the dual-frequency feed so that it is located at the focal point of the main reflecting surface and the virtual focal point of the sub-reflecting surface coincident position.

In a possible implementation manner of the first aspect, an outer tube fixing member is provided outside the dual-frequency feed source, the bottom end of the medium support is fixed on the outer tube fixing member, and the other end is connected to the secondary reflection surface.

On this basis, since the main structure of the dual-frequency feed is a low-frequency waveguide, the low-frequency waveguide is thin and the contact surface is small, which is not convenient for direct connection. An outer tube fixing member is arranged on the outer side of the low frequency waveguide, and the outer tube fixing member is beneficial to increase the contact area with the medium support and facilitate the connection between the medium support and the dual-frequency feed source.

In a possible implementation manner of the first aspect, the relative permittivity of the dielectric support ranges from 2 to 4. On this basis, by selecting a dielectric material with a relative permittivity within this value range as the material of the dielectric support, the interference of the dielectric support to the antenna signal can be reduced.

In a possible implementation manner of the first aspect, a low-frequency matching structure is provided between the low-frequency feed source and the high-frequency feed source, and the low-frequency feed source includes a low-frequency waveguide and a choke groove located on the wall of the low-frequency waveguide. The waveguide is used to transmit the first electromagnetic wave, and the opening direction of the choke groove is the same as the transmission direction of the first electromagnetic wave. The high-frequency feed source includes a high-frequency waveguide, the high-frequency waveguide is located in the low-frequency waveguide and is coaxial with the low-frequency waveguide, and the low-frequency matching structure is arranged between the high-frequency waveguide and the low-frequency waveguide. The outer radius of the high-frequency waveguide and the inner radius of the low-frequency waveguide satisfy preset conditions, so that the first electromagnetic wave excites the TEM mode, the transverse electric mode TE ₁₁ , and the transverse electric mode TE _n1 in the low-frequency waveguide. where n is a positive integer greater than 1.

On this basis, the outer radius of the high-frequency waveguide and the inner radius of the low-frequency waveguide are determined by preset conditions, so that the first electromagnetic wave can not only excite the TEM mode and the transverse electric mode TE 11 in the low-frequency waveguide, but also can excite the TEM mode and the transverse electric mode TE ₁₁ in the low-frequency waveguide. The high-order mode TE _n1 is excited in the waveguide, while the traditional antenna design does not allow the generation of high-order mode TE _n1 (n>1, and is an integer), which limits the selection range of low-frequency and high-frequency frequency bands. The present application can realize a wider combination range of the low frequency frequency band and the high frequency frequency band, so that the application range of the antenna of the present application is wider, and can be applied to the case where the frequency ratio of high frequency and low frequency is less than 3.

In a possible implementation manner of the first aspect, the preset conditions include:

The outer radius a of the high-frequency waveguide, the inner radius b of the low-frequency waveguide, and the cut-off wavelength of the transverse electric mode TE ₁₁

Satisfy the following relationship:

Cutoff wavelength of transverse electric mode TE _n1

Satisfy the following relationship:

On this basis, the above preset conditions take into account the situation that the transverse electric mode TE _n1 is generated in the low-frequency waveguide, and set the corresponding solution formula. By setting the above two formulas, the accurate outer radius of the high-frequency waveguide can be obtained. With the inner radius of the low-frequency waveguide, the first electromagnetic wave can excite the TEM mode, the transverse electric mode TE ₁₁ and the high-order mode TE _n1 in the low-frequency waveguide.

In a possible implementation manner of the first aspect, a choke groove press ring is provided on the top of the low frequency feed source, and a protective film is provided between the choke groove press ring and the choke groove. On this basis, setting the choke groove pressure ring is mainly used to fix the protective film on the choke groove. Setting the protective film on the choke groove can effectively protect the dual-frequency feed source and prevent rainwater or impurities from falling into the In the low-frequency waveguide and the dual-frequency waveguide, the function of the dual-frequency feed is affected.

In a possible implementation manner of the first aspect, the height of the inner wall of the choke groove is lower than the height of the outer wall thereof. On this basis, by setting the height of the inner wall of the choke slot to be lower than the height of the outer wall, the choke slot forms a gradually larger opening at the open end of the low-frequency waveguide, which is beneficial to the transmission of electromagnetic waves.

In a possible implementation manner of the first aspect, the high-frequency feed source is a dielectric-loaded horn or a multi-mode horn. On this basis, the high-frequency feed source can be flexibly selected according to the actual situation, so as to improve the application range of the antenna of the present application.

In a second aspect, a dual-frequency feed is provided, including a low-frequency feed and a high-frequency feed, and a low-frequency matching structure disposed between the low-frequency feed and the high-frequency feed. The low-frequency feed source includes a low-frequency waveguide and a choke slot located on the wall of the low-frequency waveguide. The low-frequency waveguide is used to transmit the first electromagnetic wave, and the opening direction of the choke slot is the same as the transmission direction of the first electromagnetic wave. The high-frequency feed source includes a high-frequency waveguide, the high-frequency waveguide is located in the low-frequency waveguide and is coaxial with the low-frequency waveguide, and the low-frequency matching structure is arranged between the high-frequency waveguide and the low-frequency waveguide. The outer radius of the high-frequency waveguide and the inner radius of the low-frequency waveguide meet the preset conditions, so that the first electromagnetic wave excites the TEM mode, the transverse electric mode TE11 and the transverse electric mode _TEn1 in the low-frequency waveguide; wherein, _n is greater than 1 positive integer.

On this basis, by setting the outer radius of the high-frequency waveguide and the inner radius of the low-frequency waveguide to meet certain preset conditions, the dual-frequency feed provided in this embodiment can support the high-order mode excited by the first electromagnetic wave , the high-order mode includes the first high-order mode TE ₁₁ , the second high-order mode TE ₂₁ , the third high-order mode TE ₃₁ , etc., so that it can be applied to the working frequency of the high-frequency waveguide and the working frequency of the low-frequency waveguide The frequency ratio between them is less than 3. Compared with the traditional antenna design, which does not support the generation of high-order modes such as TE ₂₁ and TE ₃₁ in the feed, it is not suitable for the case where the frequency ratio is less than 3. The dual-frequency feed provided in this embodiment has a wider application range and can be more Well meet the market demand.

In a possible implementation manner of the second aspect, the preset conditions include:

Satisfy the following relationship:

Cutoff wavelength of transverse electric mode TE _n1

Satisfy the following relationship:

In a possible implementation manner of the second aspect, a choke groove press ring is provided on the top of the low frequency feed source, and a protective film is provided between the choke groove press ring and the choke groove.

On this basis, setting the choke groove pressure ring is mainly used to fix the protective film on the choke groove. Setting the protective film on the choke groove can effectively protect the dual-frequency feed source and prevent rainwater or impurities from falling into the In the low-frequency waveguide and the dual-frequency waveguide, the function of the dual-frequency feed is affected.

In a possible implementation manner of the second aspect, the height of the inner wall of the choke groove is lower than the height of the outer wall thereof. On this basis, by setting the height of the inner wall of the choke slot to be lower than the height of the outer wall, the choke slot forms a gradually larger opening at the open end of the low-frequency waveguide, which is beneficial to the transmission of electromagnetic waves.

In a possible implementation manner of the second aspect, the high-frequency feed source is a dielectric-loaded horn or a multi-mode horn. On this basis, the high-frequency feed source can be flexibly selected according to the actual situation, so as to improve the application range of the antenna of the present application.

Description of drawings

Fig. 1 is one of a kind of dual-frequency antenna provided in the prior art;

Fig. 2 is the second of a kind of dual-frequency antenna provided by the prior art;

FIG. 3 is the third of a kind of dual-frequency antenna provided by the prior art;

FIG. 4 is a schematic structural diagram of a dual-frequency antenna provided by an embodiment of the present application;

FIG. 5A is a simulation analysis diagram of a dual-band antenna on the E-plane provided by an embodiment of the present application;

5B is a simulation analysis diagram of the dual-frequency antenna provided on the E surface when the dielectric support is removed according to an embodiment of the present application;

6A is a simulation analysis diagram of a dual-frequency antenna on the H-plane provided by an embodiment of the present application;

FIG. 6B is a simulation analysis diagram of the dual-frequency antenna on the H-plane when the dielectric support is removed according to an embodiment of the present application;

Fig. 7 is the partial enlarged schematic diagram of Fig. 4;

FIG. 8 is a partial enlarged schematic diagram of another embodiment of the application;

FIG. 9 is a partial enlarged schematic diagram of still another embodiment of the application;

10 is a schematic structural diagram of a dual-frequency feed provided by an embodiment of the present application;

11 is a comparison diagram of standing wave characteristics of a dual-band antenna with or without dielectric support provided by an embodiment of the application;

FIG. 12 is a comparison diagram of the pattern characteristics of a dual-band antenna provided by an embodiment of the present application with or without a medium support;

FIG. 13 is a schematic structural diagram of another dual-frequency antenna provided by an embodiment of the present application.

In the figure: 1-main reflecting surface; 2-secondary reflecting surface; 3-dielectric support; 4-dual frequency feed; 301-first connection part; 302-second support part; 303-first support part; 304- 401- low frequency feed source; 402- low frequency matching structure; 403 - high frequency feed source; 4011 - choke groove pressure ring; 4012 - outer tube fixing part; 4013 - low frequency waveguide; 4032 - High Frequency Waveguide.

Detailed ways

The technical solutions in the present application will be described below with reference to the accompanying drawings.

In the embodiments of the present application, words such as "exemplary" or "for example" are used to represent examples, illustrations or illustrations. Any embodiments or designs described in the embodiments of the present application as "exemplary" or "such as" should not be construed as preferred or advantageous over other embodiments or designs. Rather, the use of words such as "exemplary" or "such as" is intended to present the related concepts in a specific manner.

In the embodiments of the present application, sometimes _a subscript such as W1 may be mistakenly written in a non-subscript form such as W1. When the difference is not emphasized, the meaning to be expressed is the same.

In the embodiments of the present application, the terms "first" and "second" are only used for description purposes, and cannot be understood as indicating or implying relative importance or implying the number of indicated technical features. Thus, a feature defined as "first" or "second" may expressly or implicitly include one or more of that feature.

It is to be understood that the terminology used in describing the various described examples herein is for the purpose of describing particular examples and is not intended to be limiting. As used in the description of the various described examples and the appended claims, the singular forms "a", "an")" and "the" are intended to include the plural forms as well, unless the context dictates otherwise. clearly instructed.

In this application, "at least one" means one or more, and "plurality" means two or more. "At least one item(s) below" or similar expressions thereof refer to any combination of these items, including any combination of single item(s) or plural items(s). For example, at least one item (a) of a, b, or c can represent: a, b, c, a-b, a-c, b-c, or a-b-c, where a, b, c may be single or multiple .

It will also be understood that the term "and/or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items. The term "and/or" is an association relationship that describes an associated object, indicating that there can be three kinds of relationships, for example, A and/or B, which can mean that A exists alone, A and B exist simultaneously, and B exists alone. a situation. In addition, the character "/" in this application generally indicates that the related objects are an "or" relationship.

It should be understood that determining B according to A does not mean that B is only determined according to A, and B may also be determined according to A and/or other information.

It will also be understood that the term "includes" (also referred to as "includes", "including", "comprises" and/or "comprising") when used in this specification designates the presence of stated features, integers, steps, operations, elements , and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groupings thereof.

It should be understood that references throughout the specification to "one embodiment," "an embodiment," and "one possible implementation" mean that a particular feature, structure, or characteristic related to the embodiment or implementation is included in the present application at least one embodiment of . Thus, appearances of "in one embodiment" or "in an embodiment of the application", "one possible implementation" in various places throughout the specification are not necessarily referring to the same embodiment. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner in one or more embodiments.

In order to solve the problems of disordered electromagnetic field distribution, high side lobes, and deteriorating antenna patterns of dual-frequency antennas in the prior art, an embodiment of the present application provides a dual-frequency antenna to improve the pattern performance of the antenna. The following is in conjunction with FIG. 4 The embodiments of the present application will be described with reference to FIG. 13 .

Referring to FIG. 4 , FIG. 4 is a schematic structural diagram of a dual-frequency antenna provided by an embodiment of the present application. As shown in FIG. 4 , the dual-frequency antenna includes a main reflection surface 1 , a sub-reflection surface 2 , a dual-frequency feed source 4 and a medium support 3 , wherein the main reflection surface 1 and the sub-reflection surface 2 are disposed opposite to each other.

The dual-frequency feed 4 includes a low-frequency feed 401 and a high-frequency feed 403. The center frequency of the low-frequency feed 401's operating frequency band is the first center frequency, and the high-frequency feed 403's operating frequency band has the second center frequency. The medium support 3 is disposed between the main reflection surface 1 and the sub-reflection surface 2. The medium support 3 includes an annular first support portion 303 with an opening on one side. The opening of the first support portion 303 is disposed toward the sub-reflection surface 2. The first support The thickness of the portion 303 is related to the relative permittivity of the first support portion 303 , the first center frequency, and the second center frequency. The sub-reflection surface 2 is fixedly connected to the opening of the first support portion 303, and forms a cavity with the first support portion 303; the first end of the dual-frequency feed 4 is disposed in the cavity through the first support portion 303, The second end of the frequency feed 4 is connected at the center of the main reflection surface 1 .

In the embodiment of the present application, the main reflection surface 1 and the secondary reflection surface 2 may adopt structures that meet the requirements according to design requirements. Which type of main reflecting surface 1 and sub-reflecting surface 2 is specifically selected is not limited in the embodiments of the present application. The selection of the main reflecting surface 1 and the sub-reflecting surface 2 does not affect the realization of the purpose of the present application, as long as the corresponding design requirements are met. Can. For example, the main reflection surface 1 may be a standard paraboloid or a circumfocal paraboloid with a certain offset of the focus. When the main reflection surface 1 adopts a standard paraboloid, the corresponding sub reflection surface 2 can be a hyperbola or an ellipse. When the main reflection surface 1 adopts a circumfocal paraboloid, the corresponding curve of the secondary reflection surface 2 may also be an ellipse or a hyperbola. It is only an example, and this embodiment is described by taking the main reflection surface 1 as an annular focal paraboloid and the secondary reflection surface 2 as an ellipse as an example.

In the embodiment of the present application, the dielectric support 3 refers to a support structure made of dielectric materials in the field of antennas. The dielectric materials do not include materials such as metals that can strongly reflect the signal transmission of the antenna. Generally, plastics are used to interfere with electromagnetic waves. smaller material. For example, the medium material can be selected from engineering plastics, and the engineering plastics can be selected from polyphenylene ether, polycarbonate, polystyrene or polytetrafluoroethylene, etc. The specific material selected is not limited in the embodiment of this application, as long as the material supported by the medium is satisfied The interference to electromagnetic waves can be lower than the corresponding design standard. It is only an example, the dielectric support 3 in this embodiment is made of polyphenylene ether.

In the embodiment of the present application, the dual-frequency feed source 4 may be a coaxial dual-frequency feed source, and the center frequency refers to the average frequency of the working frequency band. The specific values of the first center frequency and the second center frequency of the dual-frequency feed 4 can be set as required, and do not affect the realization of the purpose of the present application. For example, when the operating frequency band of the low frequency feed 401 is 27.5-29.5 GHz, the first center frequency is 28.5 GHz, and when the operating frequency band of the high frequency feed 403 is 71-86 GHz, the second center frequency is 78.5 GHz.

In the embodiment of the present application, the shape of the annular first support portion 303 with one side open is not specifically limited. The interior of the first support portion 303 is hollow, and its opening faces the sub-reflection surface 2 . The sub-reflection surface 2 covers the opening end of the first support portion 303 and forms a cavity with the first support portion 303 . The size of the sub-reflection surface 2 is determined according to the model of the sub-reflection surface 2 specifically selected, and the size of the opening of the first support portion 303 is greater than or equal to the size of the sub-reflection surface 2 . For example, the opening of the first support portion 303 may be equal to the size of the sub-reflection surface 2 , so that the sub-reflection surface 2 just fits with the opening of the first support portion 303 .

In the embodiment of the present application, the thickness of the first support portion 303 refers to the wall thickness of the first support portion 303 . As shown in FIG. 7 , the wall thickness of the first support portion 303 is d. The first support part 303 is the main part of the dielectric support 3, and the signal of the antenna is mainly transmitted through the first support part 303. Therefore, the thickness of the first support part 303 is one of the important factors affecting the performance of the antenna pattern, and the different Therefore, when setting the thickness of the first support part 303, the relative permittivity of the first support part 303 itself and the wavelength of the electromagnetic wave passing through the first support part 303 can be referred to to reduce the first support part 303. The influence of the thickness of the support portion 303 on the performance of the antenna pattern.

In the embodiment of the present application, the first support portion 303 in the radiation core region of the dielectric support 3 is set in a ring shape, and is made of engineering plastics as the dielectric material. The interference is small, and electromagnetic transparency is achieved at the high frequency feed 403 and the low frequency feed 401 at the same time. The main body is the dielectric support 3 with a ring structure, and the thickness value of the dielectric support 3 is determined by combining the relative permittivity of the dielectric support 3, the first center frequency and the second center frequency, which is conducive to reducing side lobes and reducing The interference received by the antenna to improve the antenna pattern and improve the electrical performance of the high and low frequency bands. By setting the medium support 3 as an annular hollow support body, the structural reliability is high, and the assembly is relatively convenient.

Taking the working frequency of the low-frequency feed source 401 as 28 GHz and the working frequency of the high-frequency feed source 403 as 80 GHz as an example, simulation analysis is performed on the dual-frequency antenna of this embodiment and the dual-frequency antenna of this embodiment without the dielectric support 3 respectively. , to analyze the influence of the dielectric support 3 set according to the method described in the above embodiment on the performance of the dual-frequency antenna.

Referring to FIGS. 5A and 5B , FIG. 5A is a simulation analysis diagram of the dual-frequency antenna provided by an embodiment of the present application on the E surface, and FIG. 5B is the dual-frequency antenna provided by an embodiment of the present application when the dielectric support 3 is removed on the E surface. Simulation analysis diagram. As shown in FIG. 5A and FIG. 5B , it can be seen that the dual-frequency antenna in this embodiment has little influence on the electric field of the dual-frequency antenna on the E surface when there is a dielectric support 3 and when there is no dielectric support 3 .

6A is a simulation analysis diagram of the dual-frequency antenna provided by an embodiment of the present application on the H surface, and FIG. 6B is a simulation analysis diagram of the dual-frequency antenna provided by an embodiment of the present application on the H surface when the dielectric support 3 is removed. From FIG. 6A 6B, it can be seen that the dual-frequency antenna in this embodiment has less influence on the electric field of the dual-frequency antenna on the H surface when there is a dielectric support 3 and when there is no dielectric support 3.

FIG. 11 is a comparison diagram of standing wave characteristics of a dual-frequency antenna provided by an embodiment of the present application with or without the dielectric support 3 , and the S1 curve in FIG. 11 is the standing wave of the dual-frequency antenna of the embodiment without the dielectric support 3 The characteristic diagram, the S2 curve is the standing wave characteristic diagram of the dual-frequency antenna of this embodiment when the dielectric support 3 is provided. Comparing S1 and S2, it can be seen that the influence of the dielectric support 3 on the standing wave characteristics of the dual-frequency antenna is relatively small. Small.

FIG. 12 is a comparison diagram of the pattern characteristics of a dual-frequency antenna provided by an embodiment of the present application with or without the dielectric support 3 , and the L1 curve in FIG. 12 is the pattern characteristic of the dual-frequency antenna of this embodiment without the medium support 3 Curve, L2 curve is the pattern characteristic curve of the dual-frequency antenna in this embodiment when the dielectric support 3 is provided. Comparing L1 and L2, it can be seen that the presence of the dielectric support 3 has little influence on the pattern characteristics of the dual-frequency antenna.

In practical applications, it is impossible to directly remove the support like simulation analysis and keep the sub-reflection surface in the air. The situations shown in FIG. 5B and FIG. 6B are ideal states. It can be seen from the simulation analysis results that, in the embodiment of the present application, the introduction of the dielectric support 3 basically does not cause a change in the distribution of the radiated electric field, and electromagnetic transparency can be basically achieved.

In an embodiment of the present application, the cross section of the first support portion 303 perpendicular to the extending direction of the dual-frequency feed source 4 gradually increases along the first direction, and the first direction is the secondary reflection of the dual-frequency feed source 4 towards the secondary reflection. The direction in which face 2 extends.

As shown in FIG. 7 , in the embodiment of the present application, the first direction refers to a direction that is perpendicular to the axis of the low-frequency waveguide 4013 and points to the sub-reflection surface 2 . The cross-section of the first support portion 303 perpendicular to the extending direction of the dual-frequency feed 4 gradually increases along the first direction, that is, the first support portion 303 is gradual, and the cross-section perpendicular to the first direction is closer to the sub-reflection surface. The larger the value of 2, the first support part 303 changes in a horn shape, which is more convenient for the dual-frequency feed 4 to receive and transmit signals, reduce the influence of the dielectric support 3 on signal transmission, and reduce the generation of side lobes, which is beneficial to Improve the performance of the antenna pattern.

In the embodiment of the present application, the shape of the first support portion 303 may be a hemisphere, a truncated cone, or a prismatic shape. It should be understood that the shape of the first support portion 303 is not limited to the above-mentioned shape, and may be a deformation of the above-mentioned shape or other shapes , it is advisable that the influence of the shape of the first support portion 303 on the transmission of the antenna signal satisfies the corresponding standard, which can be the ETSI EN 302 217-4 Class 3 standard.

As shown in FIG. 7 , FIG. 7 is a partial enlarged schematic view of FIG. 4 . It is only an example, the first support part 303 in the embodiment of the present application is a hemispherical shape, and the interior of the hemispherical first support part 303 is a spherical surface, because the electromagnetic waves generated by the feed source are scattered from the dual-frequency feed source 4 . , therefore, the first support portion 303 on the spherical surface causes less interference to the transmission of the signal, which is beneficial to improve the performance of the antenna pattern.

In addition, it is only an example, the first support portion 303 may be in the shape of a truncated cone, as shown in FIG. 8 , which is a partially enlarged schematic view of another embodiment of the present application. , which greatly improves the performance of the antenna pattern. The first support portion 303 can also be in the shape of a prism, as shown in FIG. 9 , which is a partially enlarged schematic diagram of another embodiment of the application. Specifically, the prism in FIG. 9 is an octagonal prism. In practical applications, The shape of the prism can be determined according to the design requirements, such as five-sided, six-sided, etc. When the face of the prism is close to infinity, the prism is close to a circular truncated, and the prism-shaped first support portion 303 also has It is beneficial to reduce the generation of side lobes and improve the pattern performance of the antenna.

In an embodiment of the present application, the cross section of the first support portion 303 perpendicular to the extending direction of the dual-frequency feed source 4 is circular. In the embodiment of the present application, the extending direction of the dual-frequency feed source 4 refers to the straight line where the axis of the dual-frequency feed source 4 is located, that is, the cross section of the first support portion 303 perpendicular to the axis of the dual-frequency feed source 4 is circular. By setting the cross section of the first support portion 303 perpendicular to the axis of the dual-frequency feed source 4 to be circular, the shape of the opening of the first support portion 303 is closer to that of the sub-reflection surface 2 , which facilitates fixing the sub-reflection surface 2 . At the same time, the cross section of the first support portion 303 perpendicular to the axis of the dual-frequency feed source 4 is circular. The first support portion 303 has little influence on the signal transmission of the dual-frequency feed 4 , which is beneficial to the transmission of electromagnetic waves, so as to improve the characteristics of the antenna pattern.

In an embodiment of the present application, the thickness of the medium support 3 is related to the wavelength of the first half medium and the wavelength of the second half medium. Wherein, the first half medium wavelength is half of the medium wavelength of the first center frequency, and the second half medium wavelength is half of the medium wavelength of the second center frequency.

The signals transmitted by the dual-frequency feed 4 include high-frequency signals and low-frequency signals. The setting of the medium support 3 will have a certain impact on the transmission of high-frequency signals and the transmission of low-frequency signals. Therefore, when the medium support 3 is set, it can be Consider its impact on high-frequency and low-frequency signals at the same time. Since the wavelength of the high-frequency signal and the wavelength of the low-frequency signal are inconsistent, when the medium support 3 is set, the wavelength of the high-frequency signal and the wavelength of the low-frequency signal can be comprehensively considered.

In this embodiment, the thickness of the medium support 3 is related to the first half medium wavelength and the second half medium wavelength, the first half medium wavelength is half the medium wavelength of the first center frequency, and the first center frequency is the center frequency of the low-frequency signal ; The second half medium wavelength is half of the medium wavelength of the second center frequency, and the second center frequency is the center frequency of the high frequency signal. By taking the wavelength of the first half medium and the wavelength of the second half medium as the reference standard for the thickness of the medium support 3, the determined thickness of the medium support 3 can reduce the interference to the signal transmission of the antenna, and can take into account the radiation of high frequency and low frequency performance, improving antenna pattern performance.

In an embodiment of the present application, the thickness of the dielectric support 3 is 0.9-1.1N times the wavelength of the first half-medium, and is 0.9-1.1M times the wavelength of the second half-medium. Among them, N and M are positive integers.

By setting the thickness value of the dielectric support 3 to be close to the common multiple of the wavelength of the first half medium and the wavelength of the second half medium, the dielectric support 3 can take into account the radiation performance of high frequency and low frequency, and the effect is better, so that the high frequency and low frequency The electrical performance indicators should be optimized as far as possible. A ±10% error is reserved for the thickness value of the dielectric support 3. The dielectric support 3 whose thickness is within this error range has little effect on the electrical performance of the antenna, and can increase the value range of the dielectric support 3, which is convenient for the practical application of the antenna. time of production and processing.

In this embodiment, the dielectric material of the dielectric support 3 is polyphenylene oxide (PPO), the working frequency range of the low frequency feed 401 is 27.5-29.5 GHz, and the working frequency range of the high frequency feed 403 is 71 ~86GHz for a typical explanation.

The relative dielectric constant of polyphenylene ether is 2.55, the first center frequency is the center frequency of the low frequency signal, so the first center frequency is 28.5GHz, and the second center frequency is the center frequency of the high frequency signal, so the second center frequency is 78.5 GHz. The formula for calculating the medium wavelength is:

Among them, C is the speed of light, the value of C is 3×10 ⁸ m/s, f is the frequency, and ∈ _r is the relative permittivity. The wavelength of the first half medium is half the wavelength of the first medium, and the wavelength of the second half medium is half the wavelength of the second medium. According to the above formula, it can be obtained:

The first half medium wavelength λ ₁ is:

The second half-medium wavelength λ ₂ is:

According to the value of the wavelength of the first half medium, the optional value of N times the wavelength of the first half medium is: 3.3mm, 6.6mm, 9.9mm, etc. According to the value of the wavelength of the second half medium, it can be known that the wavelength of the second half medium is M times optional values are: 1.2mm, 2.4mm, 3.6mm, 4.8mm, etc. The optional value of N times the wavelength of the first half medium, 3.3mm, is close to 3.6mm, the optional value of M times the wavelength of the second half medium, because the thickness of the dielectric support 3 can fluctuate on the basis of the above values. Therefore, considering the wavelength of the first half medium and the wavelength of the second half medium comprehensively, the thickness of the medium support 3 in this embodiment may be 3.6 mm.

It should be noted that the thickness of the dielectric support 3 is not unique. For example, in this embodiment, the thickness of the dielectric support 3 can be between 3 and 4 mm. The impact of performance is determined, whichever can meet the design requirements.

In an embodiment of the present application, the thickness of the medium support 3 is X times the wavelength of the first half medium, and is 0.9-1.1M times the wavelength of the second half medium. Wherein, X≤0.25, M is a positive integer.

When the frequency between the high frequency and the low frequency is relatively large, the integer multiple of the wavelength of the second half medium is used as a reference for the thickness of the dielectric support 3, and the thickness of the dielectric support 3 can be kept ±10% on this basis. tolerance scope. In this case, the thickness of the dielectric support 3 is much smaller than the length of the wavelength of the first half of the medium, so a quarter of the wavelength of the first half of the medium can be selected as the reference threshold for the thickness of the dielectric support 3, so that the thickness of the dielectric support 3 is The thickness is less than or equal to the reference threshold, so that the radiation performance of high frequency and low frequency can be considered as much as possible, so that the electrical performance of the two frequency bands can meet the design requirements.

In this embodiment, the dielectric material of the dielectric support 3 is polyphenylene ether, the center frequency of the working frequency band of the low-frequency feed source 401 is 18 GHz, and the center frequency of the working frequency band of the high-frequency feed source 403 is 80 GHz. .

The relative permittivity of polyphenylene ether is 2.55, the first center frequency is the center frequency of the working frequency band of the low frequency feed 401 , so the first center frequency is 18GHz, and the second center frequency is the center of the working frequency band of the high frequency feed 403 frequency, so the second center frequency is 80GHz. At this time, the frequency ratio between the high frequency and the low frequency is greater than 3.

The formula for calculating the medium wavelength is:

Among them, C is the speed of light, the value of C is 3×10 ⁸ m/s, f is the frequency, and ∈ _r is the relative permittivity. The wavelength of the first half medium is half the wavelength of the first medium, and the wavelength of the second half medium is half the wavelength of the second medium. According to the above formula, the first half medium wavelength can be obtained when the frequency ratio between the high frequency and the low frequency is greater than 3 and the second half medium wavelength:

The first half medium wavelength _λ3 is:

The second half-medium wavelength _λ4 is:

Since the value of the wavelength of the first half medium and the wavelength of the second half medium is quite different (whether the ratio between the two is greater than 3 can be used as a reference), the wavelength of the second half medium is much smaller than the wavelength of the first half medium. In this case, It is not appropriate to determine the thickness of the dielectric support 3 based on the common multiple of the wavelength of the first half medium and the wavelength of the second half medium. At this time, the thickness of the medium support 3 can be referred to according to the thickness of the second half medium wavelength λ ₄ and the quarter of the first half medium wavelength as the threshold value. Therefore, considering the wavelength of the first half medium and the wavelength of the second half medium comprehensively, the thickness of the medium support 3 in this embodiment may be 1.2 mm.

It should be noted that the value of the thickness of the medium support 3 may have a certain error, for example, the error range is ±10%. For example, in this embodiment, the value of the medium support 3 may be 1.2 mm, 1.1 mm or 1.3 mm. mm, it can also be in the range of 1.1mm to 1.3mm, 1.2mm is the optimal value for comprehensive consideration, but it is not limited that the thickness of the dielectric support 3 must be this value. The impact on the performance of the antenna should not exceed the design requirements. The method for determining the thickness of the dielectric support 3 introduced in this embodiment is mainly applied to the case where the frequency ratio of high frequency and low frequency is less than 3, but it is not limited that when the frequency ratio of high frequency and low frequency is less than 3, only this embodiment can be used. The method described in the example is used to obtain the value.

It should be noted that, when the frequency ratio of the high frequency to the low frequency is around 3, the thickness of the dielectric support 3 can be determined according to any method in the foregoing embodiments. For example, when the center frequency of the low frequency and the high frequency When the center frequency combination of low frequency and high frequency is 23GHz&80GHz, the thickness of dielectric support 3 can be 1.2mm or 3.6mm; when the center frequency combination of low frequency and high frequency is 26GHz&80GHz, or 28GHz&80GHz, the thickness of dielectric support 3 The value can also be 1.2mm or 3.6mm. The following is a simple list of the reference values of the thickness of the dielectric support 3 when different frequency bands are combined, as shown in Table 1:

Table 1

低频中心频率与高频中心频率组合Combination of low frequency center frequency and high frequency center frequency	介质支撑3的厚度d的参考取值Reference value of thickness d of dielectric support 3
15GHz&80GHz15GHz&80GHz	1.2mm1.2mm
18GHz&80GHz18GHz&80GHz	1.2mm1.2mm
23GHz&80GHz23GHz&80GHz	1.2mm或者3.6mm1.2mm or 3.6mm
26GHz&80GHz26GHz&80GHz	1.2mm或者3.6mm1.2mm or 3.6mm
28GHz&80GHz28GHz&80GHz	1.2mm或者3.6mm1.2mm or 3.6mm
32GHz&80GHz32GHz&80GHz	2.4mm2.4mm
38GHz&80GHz38GHz&80GHz	2.4mm2.4mm

Referring to FIG. 7 , FIG. 7 is a partial enlarged schematic view of FIG. 4 . As shown in FIG. 7 , in an embodiment of the present application, the medium support 3 includes a first support portion 303 , and the shape of the first support portion 303 is hemispherical. Since the dual-frequency feed 4 radiates spherical waves during signal transmission, the signals are also basically spherically transmitted and received. Therefore, setting the outer shape of the first support portion 303 to be a hemispherical shape can make the shape of the first support portion 303 closer to the shape formed by electromagnetic wave transmission. The outer shape of the first support portion 303 is hemispherical. Since the first support portion 303 is an annular hollow support body, its thickness d is a certain value, so its interior is also hemispherical. The dual-frequency feed 4 is located inside the first support portion 303, and the hemispherical first support portion 303 can make the transmission direction of the electromagnetic wave be perpendicular to the surface of the first support portion 303 as much as possible, so as to reduce the refraction of the electromagnetic wave, thereby reducing the refraction of the electromagnetic wave. The influence of the dielectric support 3 on signal transmission is reduced, and the performance of the antenna pattern is improved.

In an embodiment of the present application, the medium support 3 further includes a first connection part 301 , a second support part 302 and a second connection part 304 . The first connection part 301 , the second support part 302 , the first support part 303 and the The two connection parts 304 are connected in sequence, the first connection part 301 is connected to the sub-reflection surface 2 , and the second connection part 304 is connected to the dual-frequency feed source 4 .

The main part of the dielectric support 3 is the first support part 303 , but because the dielectric support 3 is fixed on the dual-frequency feed 4 , and the top of the dielectric support 3 is connected to the sub-reflection surface 2 for supporting the sub-reflection surface 2 . Therefore, the medium support 3 further includes a first connection part 301 and a second connection part 304. The first connection part 301 is located on the side of the first support part 303 close to the sub-reflection surface 2, and is used to connect the first support part 303 and the sub-reflection surface. 2. The first support portion 303 is provided with an adaptation structure connected to the sub-reflection surface 2 . The first support portion 303 and the secondary reflection surface 2 can be fixed by means of gluing, such as using Super X 8008 black glue for adhesion, of course, other means can also be used for fixing, such as screw connection, snap connection, etc. , the embodiment of the present application does not limit the specific connection method between the first support portion 303 and the sub-reflection surface 2 .

The second connection portion 304 is located on the side of the first support portion 303 close to the dual-frequency feed source 4, and is used to fix the first support portion 303 on the dual-frequency feed source 4. The second connection portion 304 is provided with a connection with the dual-frequency feed source 4. Adapter structure to which source 4 is connected. A second support portion 302 is also provided between the first connection portion 301 and the first support portion 303. The main function of the second support portion 302 is to adjust the position of the secondary reflection surface 2 so that the dual-frequency feed 4 is located on the main reflection surface. 1 at the focal point and at the virtual focal point of the secondary reflection surface 2. The second support portion 302 and the first support portion 303 may be two independent components, which are then connected together, or may be integrally formed; correspondingly, the first connection portion 301 and the second support portion 302 may be integrally formed , or two independent parts are connected together by bonding or welding; the second connecting part 304 and the first supporting part 303 can be integrally formed, or two independent parts can be connected by bonding or welding etc. are connected together. The height of the second support portion 302 is mainly determined according to the position of the signal receiving and sending point of the dual-frequency feed 4 , the position of the first support portion 303 and the structure of the sub-reflection surface 2 .

Referring to FIG. 4 , FIG. 4 is a schematic structural diagram of a dual-frequency antenna provided by an embodiment of the present application. As shown in Figure 4, first determine the position of the main reflection surface 1, then connect the bottom end of the dual-frequency feed 4 to the center of the main reflection surface 1, and the axis of the dual-frequency feed 4 coincides with the axis of the main reflection surface 1 . By setting the height of the low-frequency waveguide 4013 on the dual-frequency feed source 4 , the signal receiving and sending point of the dual-frequency feed source 4 is located at the focal point of the main reflection surface 1 . Then, fix the medium support 3 on the dual-frequency feed source 4 , and then fix the sub-reflection surface 2 on the top of the medium support 3 . The relationship between the sub-reflection surface 2 , the medium support 3 and the dual-frequency feed source 4 is shown in FIG. 5 . When the structure of the sub-reflection surface 2 is determined, the position of its focal point (or virtual focus) can be determined. Since the position of the dual-frequency feed 4 is fixed, the distance between the secondary reflection surface 2 and the dual-frequency feed 4 can be adjusted by setting the height of the second support portion 302, so that the signal receiving and sending point of the dual-frequency feed 4 is located in the secondary The focal point (or virtual focus) of the reflection surface 2, so that the signal receiving and sending point of the dual-frequency feed 4 is located at the intersection of the main reflection surface 1 and the focal point (or virtual focus) of the secondary reflection surface 2 at the same time.

In an embodiment of the present application, an outer tube fixing member 4012 is provided outside the dual-frequency feed 4 , the bottom end of the medium support 3 is fixed on the outer tube fixing member 4012 , and the other end is connected to the secondary reflection surface 2 . Because the main support structure of the dual-frequency feed 4 is the outer low-frequency waveguide 4013, the low-frequency waveguide 4013 is thin and the contact surface is small, which is inconvenient for direct connection, and the dielectric support 3 is fixed on the dual-frequency feed 4. Therefore, by arranging the outer tube fixing member 4012 on the outside of the dual-frequency feed source 4, the outer tube fixing member 4012 is beneficial to increase the contact area with the medium support 3 and facilitate the connection between the medium support 3 and the dual-frequency feed source 4. The pipe fixing member 4012 mainly plays the role of fixing and supporting the medium support 3 . The shape of the outer tube fixing member 4012 can be determined according to actual needs. For example, when processing the low-frequency waveguide 4013 in the dual-frequency feed source 4, a supporting platform can be integrally formed on the low-frequency waveguide 4013 for fixing and supporting the medium support. 3.

In this embodiment, exemplarily, the shape of the outer tube fixing member 4012 can be set as shown in FIG. 7 , the outer tube fixing member 4012 includes a tube body sleeved on the outer side of the low-frequency waveguide 4013, and is arranged at the bottom of the tube body the annular support plate. The tube body and the support plate can be integrally formed or connected and fixed. A concave-convex structure is provided between the tube body and the low-frequency waveguide 4013 , so that the cooperation between the tube body and the low-frequency waveguide 4013 is tighter. The medium support 3 is fixed on the support plate on the outer tube fixing member 4012, that is, the second connecting part 304 on the medium support 3 is fixed on the support plate of the outer tube fixing member 4012, which can be fixed by glue, and the glue can be Super X 8008 vinyl, but not limited to this, you can choose the appropriate glue according to the actual situation.

In addition, the medium support 3 and the outer tube fixing member 4012 can also be fixed by means of screw fixing or snap-fastening. FIG. 7 is an example, which shows the second connection portion 304 and the outer tube fixing member when screw fixing is used. Threaded holes provided on the support plate on the 4012. The fixing method between the medium support 3 and the outer tube fixing member 4012 can be flexibly selected according to the actual situation, which is not repeated in this embodiment.

In an embodiment of the present application, the relative permittivity of the dielectric support 3 ranges from 2 to 4. By selecting a dielectric material with a relative permittivity within this value range as the material of the dielectric support 3, the interference of the dielectric support 3 to the antenna signal can be reduced. Materials such as polyphenylene ether, polycarbonate, polystyrene or polytetrafluoroethylene can be used as the material of the medium support 3 .

In an embodiment of the present application, a low-frequency matching structure 402 is disposed between the low-frequency feed source 401 and the high-frequency feed source 403, and the low-frequency feed source 401 includes a low-frequency waveguide 4013 and a choke groove located on the wall of the low-frequency waveguide 4013, The low-frequency waveguide 4013 is used to transmit the first electromagnetic wave, and the opening direction of the choke groove is the same as the transmission direction of the first electromagnetic wave. The high-frequency feed 403 includes a high-frequency waveguide 4032. The high-frequency waveguide 4032 is located in the low-frequency waveguide 4013 and is coaxial with the low-frequency waveguide 4013. The low-frequency matching structure 402 is arranged between the high-frequency waveguide 4032 and the low-frequency waveguide 4013. between. The outer radius of the high-frequency waveguide 4032 and the inner radius of the low-frequency waveguide 4013 satisfy preset conditions, so that the first electromagnetic wave excites the TEM mode, the transverse electric mode TE ₁₁ and the transverse electric mode TE _n1 in the low-frequency waveguide 4013 . where n is a positive integer greater than 1.

Referring to FIG. 10 , FIG. 10 is a schematic structural diagram of a dual-frequency feed provided by an embodiment of the present application. As shown in FIG. 10 , in this embodiment, the low-frequency feed source 401 includes a low-frequency waveguide 4013 and a choke groove disposed on the low-frequency waveguide 4013 . The high-frequency feed source 403 adopts a dielectric loading horn. The high-frequency feed source 403 includes a high-frequency waveguide 4032 and a dielectric head 4031. The dielectric head 4031 is arranged at the open end of the high-frequency waveguide 4032. Top of low frequency waveguide 4013 with choke groove. A low-frequency matching structure 402 is disposed between the low-frequency waveguide 4013 and the high-frequency waveguide 4032 , and the low-frequency matching structure 402 may be composed of multiple concentric dielectric columns or metal rings. The low frequency matching structure 402 can change the characteristic impedance of the waveguide and reduce the generation of reflections. The embodiment of the present application does not limit the specific structure of the low-frequency matching structure 402, as long as the corresponding design requirements are met. A choke groove is arranged _on the tube wall of the low-frequency waveguide 4013, and the opening direction of the choke groove is the same as the transmission direction of the first electromagnetic wave. The superposition of TM ₁₁ and TE ₁₁ can make the electric field distribution of the first electromagnetic wave more uniform and maximize the gain effect of the antenna. The embodiment of the present application does not limit the specific structure of the choke groove, and the settings of the choke groove only need to meet the corresponding design requirements, and the specific size and position settings of the choke groove are not described in detail in this embodiment.

It should be noted that the height of the high-frequency waveguide 4032 may be the same as the height of the low-frequency waveguide 4013 , or the height of the high-frequency waveguide 4032 may be lower than the height of the low-frequency waveguide 4013 . The high-frequency feed source 403 includes high-frequency electromagnetic waves and low-frequency electromagnetic waves. For example, the working frequency range of the low-frequency feed source 401 is 27.5-29.5 GHz, and the working frequency range of the high-frequency feed source 403 is 71-86 GHz, so 27.5-29.5 GHz is the electromagnetic wave , 71-86GHz are high-frequency electromagnetic waves, and the first electromagnetic wave refers to low-frequency electromagnetic waves.

The setting of the preset conditions is mainly used to determine the outer radius of the high-frequency waveguide 4032 and the inner radius of the low-frequency waveguide 4013. In this embodiment, the preset conditions are set to determine the outer radius of the high-frequency The inner radius is such that the first electromagnetic wave in the dual-frequency feed 4 of this size can not only excite the TEM mode and the transverse electric mode TE ₁₁ in the low-frequency waveguide 4013 , but also excite the high-order mode TE _n1 in the low-frequency waveguide 4013 . The traditional antenna design does not allow the generation of the high-order mode TE _n1 , which limits the selection range of the low-frequency frequency band and the high-frequency frequency band. In contrast, the antenna in this embodiment can achieve a wider combination range of the low-frequency frequency band and the high-frequency frequency band. This makes the application range of the antenna of the present application wider, and can be applied to the case where the frequency ratio of high frequency and low frequency is less than 3.

In an embodiment of the present application, the preset conditions include:

The outer radius a of the high-frequency waveguide 4032, the inner radius b of the low-frequency waveguide 4013, the cut-off wavelength of the transverse electric mode _TE11

Satisfy the following relationship:

Cutoff wavelength of transverse electric mode TE _n1

Satisfy the following relationship:

In the embodiment of the present application, the low-frequency waveguide 4013 will excite the TE ₁₁ mode and the TE _n1 mode of the first electromagnetic wave, and the TE _n1 mode may include high-order mode TE ₂₁ , high-order mode TE ₃₁ , etc. When the high-order mode TE ₂₁ is generated, the high-frequency waveguide The outer radius a of 4032, the inner radius b of the low-frequency waveguide 4013, the cutoff wavelength of the high-order mode TE ₂₁

Satisfy the following relationship:

When the high-order mode TE ₃₁ is generated, the outer radius a of the high-frequency waveguide 4032, the inner radius b of the low-frequency waveguide 4013, the cutoff wavelength of the high-order mode TE ₃₁

Satisfy the following relationship:

And so on when higher-order transverse electric modes are generated. When the working frequency band of the high-frequency waveguide 4032 is the E-band (71-76GHz and 81-86GHz) microwave frequency band, the inner radius of the high-frequency waveguide 4032 can be 1.5mm-1.6mm. The waveguide 4032 has a certain thickness. Considering the reliability of the high-frequency waveguide 4032 and the difficulty in actual processing, the thickness of the high-frequency waveguide 4032 can range from 1 mm to 2 mm. The value range of the radius a may be 2.5mm to 3.6mm.

The above preset conditions take into account the situation that the transverse electric mode TE _n1 is generated in the low-frequency waveguide 4013, and set the corresponding solution formula. By setting the above formula, the exact outer radius of the high-frequency waveguide 4032 and the low-frequency waveguide can be obtained. The inner radius of 4013 is such that the first electromagnetic wave can excite the TEM mode, the transverse electric mode TE ₁₁ and the higher-order mode TE _n1 in the low-frequency waveguide 4013 .

In actual use, since the feeding method generally adopts differential feeding, the electric field is in antiphase on both sides of the waveguide, while the high-order mode TE ₂₁ and high-order mode TE ₃₁ are in phase on both sides of the waveguide, although the coaxial low-frequency waveguide 4013 and high-frequency waveguide ₄₀₃₂ support high-order modes such as TE ₂₁ and TE ₃₁ , but differential feeding causes high-order modes such as TE ₂₁ and TE ₃₁ to not be _excited . There is no effect, which is not considered by the existing coaxial dual-frequency feed.

In an embodiment of the present application, a choke groove press ring 4011 is provided on the top of the low frequency feed source 401 , and a protective film is provided between the choke groove press ring 4011 and the choke groove. The choke groove pressure ring 4011 is mainly used to fix the protective film on the choke groove. Setting the protective film on the choke groove can effectively protect the dual-frequency feed source 4 and prevent rainwater or impurities from falling into the low-frequency waveguide 4013 And inside the dual-frequency waveguide, the function of the dual-frequency feed 4 is affected.

As shown in FIG. 7 , in an embodiment of the present application, the height of the inner wall of the choke groove is lower than the height of the outer wall thereof. The height of the inner wall of the choke slot is set lower than the height of the outer wall, so that the choke slot forms a gradually enlarged opening at the open end of the low-frequency waveguide 4013, which is beneficial to the transmission of electromagnetic waves.

In an embodiment of the present application, the high-frequency feed 403 is a dielectric-loaded horn or a multi-mode horn. Referring to FIG. 13 , FIG. 13 is a schematic structural diagram of another dual-frequency antenna provided by an embodiment of the present application. As shown in FIG. 13 , the high-frequency feed 403 can be a multi-mode horn. In actual use, an appropriate high-frequency feed 403 can be selected according to the actual situation to improve the application range of the antenna of the present application. The high-frequency feed 403 The choices are not limited to the above-mentioned choices.

The present application also provides a dual-frequency feed, including a low-frequency feed 401 and a high-frequency feed 403, and a low-frequency matching structure 402 disposed between the low-frequency feed 401 and the high-frequency feed 403, where the low-frequency feed 401 includes a low-frequency feed The waveguide 4013 and the choke slot located on the wall of the low-frequency waveguide 4013, the low-frequency waveguide 4013 is used to transmit the first electromagnetic wave, and the opening direction of the choke slot is the same as the transmission direction of the first electromagnetic wave; The high-frequency waveguide 4032, the high-frequency waveguide 4032 is located in the low-frequency waveguide 4013, and is coaxial with the low-frequency waveguide 4013, and the low-frequency matching structure 402 is arranged between the high-frequency waveguide 4032 and the low-frequency waveguide 4013; the high-frequency waveguide 4032 The outer radius of the low-frequency waveguide 4013 and the inner radius of the low-frequency waveguide 4013 satisfy the preset conditions, so that the first electromagnetic wave excites the TEM mode, the transverse electric mode TE11 and the transverse electric mode _TEn1 in the low-frequency waveguide 4013; wherein, _n is a positive value greater than 1 Integer.

On the basis of the above embodiment, the preset conditions include:

Satisfy the following relationship:

Cutoff wavelength of transverse electric mode TE _n1

Satisfy the following relationship:

In an embodiment of the present application, a choke groove press ring 4011 is provided on the top of the low frequency feed source 401 , and a protective film is provided between the choke groove press ring 4011 and the choke groove.

In an embodiment of the present application, the height of the inner wall of the choke groove is lower than the height of the outer wall thereof. By setting the height of the inner wall of the choke slot to be lower than the height of the outer wall, the choke slot forms a gradually larger opening at the open end of the low-frequency waveguide 4013, which is beneficial to the transmission of electromagnetic waves.

In an embodiment of the present application, the high-frequency feed 403 is a dielectric-loaded horn or a multi-mode horn. The high-frequency feed source 403 can be flexibly selected according to the actual situation, so as to improve the application range of the antenna of the present application.

The present application has introduced the dual-frequency feed in detail in the above-mentioned embodiments of the dual-frequency antenna. For the structural analysis and beneficial effects of the dual-frequency feed, please refer to the relevant content in the above-mentioned dual-frequency antenna. will not go into details.

The above are only specific embodiments of the present application, but the protection scope of the present application is not limited to this. should be covered within the scope of protection of this application. Therefore, the protection scope of this application should be subject to the protection scope of the claims.

The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments, and the same and similar parts between the various embodiments may be referred to each other.

Although the preferred embodiments of the embodiments of the present application have been described, those skilled in the art may make additional changes and modifications to these embodiments once the basic inventive concepts are known. Therefore, the appended claims are intended to be construed to include the preferred embodiments as well as all changes and modifications that fall within the scope of the embodiments of the present application.

The dual-frequency feed and dual-frequency antenna provided by the present application have been introduced in detail above. The principles and implementations of the present application are described with specific examples in this paper. The descriptions of the above embodiments are only used to help understanding The method of the present application and its core idea; at the same time, for those of ordinary skill in the art, according to the idea of the present application, there will be changes in the specific implementation and application scope. In summary, the content of this specification should not be It is construed as a limitation of this application.

Claims

A dual-frequency antenna is characterized in that it includes a main reflection surface, a secondary reflection surface, a dual-frequency feed source and a medium support,

in,

the main reflection surface and the secondary reflection surface are arranged opposite to each other;

The dual-frequency feed source includes a low-frequency feed source and a high-frequency feed source, the center frequency of the operating frequency band of the low-frequency feed source is the first center frequency, and the center frequency of the operating frequency band of the high-frequency feed source is the second center frequency;

The medium support is disposed between the main reflection surface and the sub-reflection surface, and includes an annular first support portion with an opening on one side, the opening of the first support portion is disposed toward the sub-reflection surface, and the the thickness of the first support part is related to the relative permittivity of the first support part, the first center frequency and the second center frequency;

The secondary reflection surface is fixedly connected with the opening of the first support portion, and forms a cavity with the first support portion;

The first end of the dual-frequency feed source is disposed in the cavity through the first support portion, and the second end of the dual-frequency feed source is connected at the center of the main reflection surface.
The dual-frequency antenna according to claim 1, wherein the cross section of the first support portion perpendicular to the extending direction of the dual-frequency feed source gradually increases along the first direction, and the first direction is the The direction in which the dual-frequency feed source extends toward the sub-reflection surface.
The dual-frequency antenna according to claim 1 or 2, wherein a cross-section of the first support portion perpendicular to the extending direction of the dual-frequency feed source is circular.
The dual-frequency antenna according to any one of claims 1 to 3, wherein the thickness of the dielectric support is related to the wavelength of the first half medium and the wavelength of the second half medium;

Wherein, the first half medium wavelength is half the medium wavelength of the first center frequency, and the second half medium wavelength is half the medium wavelength of the second center frequency.
The dual-band antenna according to claim 4, wherein the thickness of the dielectric support is 0.9-1.1N times the wavelength of the first half-medium, and is 0.9-1.1M times the wavelength of the second half-medium times;

Among them, N and M are positive integers.
The dual-band antenna according to claim 4, wherein the thickness of the medium support is X times the wavelength of the first half medium, and is 0.9-1.1M times the wavelength of the second half medium;

Wherein, X≤0.25, M is a positive integer.
The dual-frequency antenna according to any one of claims 1 to 6, wherein the shape of the first support portion is hemispherical.
The dual-band antenna according to any one of claims 1 to 7, wherein the dielectric support further comprises a first connection part, a second support part and a second connection part, the first connection part, the The second support part, the first support part and the second connection part are connected in sequence, the first connection part is connected with the secondary reflection surface, and the second connection part is connected with the dual-frequency feed source.
The dual-frequency antenna according to any one of claims 1 to 8, wherein an outer tube fixing member is provided outside the dual-frequency feed source, and the bottom end of the medium support is fixed on the outer tube fixing member , and the other end is connected to the sub-reflection surface.
The dual-frequency antenna according to any one of claims 1 to 9, wherein the relative permittivity of the dielectric support ranges from 2 to 4.
The dual-frequency antenna according to any one of claims 1 to 10, wherein a low-frequency matching structure is arranged between the low-frequency feed source and the high-frequency feed source;

The low-frequency feed source includes a low-frequency waveguide and a choke slot on the wall of the low-frequency waveguide, the low-frequency waveguide is used for transmitting first electromagnetic waves, and the opening direction of the choke slot is the same as the direction of the first electromagnetic wave. The transmission direction is the same;

The high-frequency feed source includes a high-frequency waveguide, the high-frequency waveguide is located in the low-frequency waveguide and is coaxial with the low-frequency waveguide, and the low-frequency matching structure is arranged between the high-frequency waveguide and the low-frequency waveguide. between the low-frequency waveguides;

The outer radius of the high-frequency waveguide and the inner radius of the low-frequency waveguide satisfy preset conditions, so that the first electromagnetic wave excites the TEM mode, the transverse electric mode TE 11 and the transverse electric mode TE n1 in the low-frequency waveguide ;

where n is a positive integer greater than 1.
The dual-band antenna according to claim 11, wherein the preset conditions include:

The outer radius a of the high-frequency waveguide, the inner radius b of the low-frequency waveguide, and the cut-off wavelength of the transverse electric mode TE 11
Satisfy the following relationship:

The cut-off wavelength of the transverse electrical mode TE n1
Satisfy the following relationship:
The dual-band antenna according to claim 11 or 12, wherein a choke groove pressing ring is provided on the top of the low frequency feed source, and a protection is provided between the choke groove pressing ring and the choke groove membrane.
The dual-frequency antenna according to any one of claims 11 to 13, wherein the height of the inner wall of the choke groove is lower than the height of the outer wall thereof.
The dual-frequency antenna according to any one of claims 11 to 14, wherein the high-frequency feed source is a dielectric-loaded horn or a multi-mode horn.
A dual-frequency feed, characterized in that it includes a low-frequency feed and a high-frequency feed, and a low-frequency matching structure disposed between the low-frequency feed and the high-frequency feed,

The low-frequency feed source includes a low-frequency waveguide and a choke slot on the wall of the low-frequency waveguide, the low-frequency waveguide is used for transmitting first electromagnetic waves, and the opening direction of the choke slot is the same as the direction of the first electromagnetic wave. The transmission direction is the same;

The high-frequency feed source includes a high-frequency waveguide, the high-frequency waveguide is located in the low-frequency waveguide and is coaxial with the low-frequency waveguide, and the low-frequency matching structure is arranged between the high-frequency waveguide and the low-frequency waveguide. between the low-frequency waveguides;

The outer radius of the high-frequency waveguide and the inner radius of the low-frequency waveguide satisfy preset conditions, so that the first electromagnetic wave excites the TEM mode, the transverse electric mode TE 11 and the transverse electric mode TE n1 in the low-frequency waveguide ;

where n is a positive integer greater than 1.
The dual-frequency feed according to claim 16, wherein the preset conditions include:

The outer radius a of the high-frequency waveguide, the inner radius b of the low-frequency waveguide, and the cut-off wavelength of the transverse electric mode TE 11
Satisfy the following relationship:

The cut-off wavelength of the transverse electrical mode TE n1
Satisfy the following relationship:
The dual-frequency feed source according to claim 16 or 17, wherein a choke groove pressure ring is arranged on the top of the low frequency feed source, and a choke groove pressure ring is arranged between the choke groove pressure ring and the choke groove. protective film.
The dual-frequency feed source according to any one of claims 16 to 18, wherein the height of the inner wall of the choke groove is lower than the height of the outer wall thereof.
The dual-frequency feed source according to any one of claims 16 to 19, wherein the high-frequency feed source is a dielectric-loaded horn or a multi-mode horn.