WO2019227301A1

WO2019227301A1 - Antenna feed structure, antenna, and microwave transmission apparatus

Info

Publication number: WO2019227301A1
Application number: PCT/CN2018/088807
Authority: WO
Inventors: 张鲁奇; 吕瑞
Original assignee: 华为技术有限公司
Priority date: 2018-05-29
Filing date: 2018-05-29
Publication date: 2019-12-05

Abstract

The embodiments of the present application relate to the technical field of antennas, and provide an antenna feed structure, an antenna, and a microwave transmission apparatus. The antenna feed structure comprises a horn feed and a reflecting plate, the reflecting plate being provided at a radiation aperture of the horn feed. The reflecting plate can change the direction of electromagnetic wave transmission in an antenna near field region outside the radiation aperture of the horn feed, thereby causing the horn feed to form a beam pointing in a predetermined direction.

Description

Antenna feed structure, antenna and microwave transmission equipment

Technical field

The present application relates to the field of antenna technology, and in particular, to an antenna feed structure, an antenna, and a microwave transmission device.

Background technique

An antenna is a transformer that transforms a guided wave propagating on a transmission line into an electromagnetic wave propagating in an unbounded medium (usually free space) or vice versa. An antenna is a component used in radio equipment to transmit or receive electromagnetic waves. In engineering systems such as radio communications, broadcasting, television, radar, navigation, electronic countermeasures, remote sensing, radio astronomy, etc., all uses electromagnetic waves to transmit information, relying on antennas to work. In addition, in terms of transmitting energy by electromagnetic waves, non-signal energy radiation also requires an antenna.

In scenarios such as long-distance microwave backhaul and satellite communication, high-gain antennas are generally used due to long transmission distances and severe interference. High-gain antennas are relatively narrower in the radiation direction and radiate in certain directions. More concentrated antenna. In order to improve the reliability of communication, a high-gain antenna is required to have a certain beam scanning or detection function. To this end, a surface antenna can be used with multiple feed sources to work. Features.

Taking beam scanning as an example, in order to achieve a wide range of beam scanning, multiple feed sources with their normals parallel to each other can be set, with one feed source located in the middle pointing in the direction of maximum gain. Due to the larger diameter of the horn feed, the distance between the feed on both sides and the feed in the middle is relatively long, which results in a large beam gap between the beams on both sides and the feed in the middle. The gain area cannot achieve full beam coverage.

In order to solve the above problem, in an antenna feed structure, the feed beam direction required in the system is obtained by spatially deflecting the feed. As shown in FIG. 1, the antenna feed structure includes a first speaker feed 01, a second speaker feed 02, and a third speaker feed 03, and the second speaker feed 02 is located at the first speaker feed 01 and the third speaker Feed 03. In order to make the first horn feed 01 and the third horn feed 03 on both sides also point to the maximum gain direction, deflect the first horn feed 01 and the third horn feed 03 to the second horn feed 02, so that both sides The maximum gain direction of the feed is closer to the maximum gain direction of the intermediate feed, which can improve the high-gain beam scanning function of the surface antenna in a multi-feed system to a certain extent.

However, in the feed system shown in FIG. 1, because the feeds on both sides are deflected, the overall lateral size of the three feeds is increased, and it is difficult to achieve full coverage of the beam at half power angle in the scanning range; And when multiple single-feed sources with space deflection are combined for installation, the assembly is also difficult.

Summary of the Invention

The embodiments of the present application provide an antenna feed structure, an antenna, and a microwave transmission device, and solve the problems of large lateral size and difficult assembly of a feed with a specific beam pointing function.

In a first aspect, the present application provides an antenna feed structure including a horn feed and a reflection plate. The reflection plate is disposed at the radiation aperture of the horn feed. The reflection plate can change the near-field area of the antenna outside the radiation aperture of the horn feed The direction of the electromagnetic wave propagation makes the horn feed form a preset beam direction.

In the antenna feed structure provided in the embodiment of the present application, since a reflection plate is provided at the radiation aperture of the horn feed, and the reflection plate can change the electromagnetic wave propagation direction of the antenna near field area outside the radiation aperture of the horn feed, thereby, The horn feed does not need to be deflected to make the horn feed form a preset beam direction, which does not increase the lateral size of the horn feed. When scanning with multiple feeds, it is easy to achieve a half-power angle in the scanning range. Full beam coverage. In addition, the speaker feed of this structure does not need to be installed obliquely, thereby solving the problem of difficulty in oblique installation.

In a possible implementation manner, the reflection plate is disposed within a range of a feed irradiation angle of the horn feed. Therefore, the reflector can change the beam direction when the horn feed source is irradiated to the surface antenna, thereby improving the performance of the surface antenna.

In a possible implementation manner, the included angle between the reflection plate and the feed normal direction of the horn feed is greater than or equal to 0 degrees and less than 45 degrees. Therefore, the effect of changing the beam pointing can be made obvious, but it will not affect the radiation intensity of the speaker feed.

In a possible implementation manner, the reflection plate is entirely located in the near-field area of the antenna. Therefore, the reflecting plate is caused to change the direction of the feed beam only in the non-far field region.

In a possible implementation manner, in a direction parallel to the end face where the radiation aperture of the horn feed is located, the maximum width of the reflection plate is less than or equal to the width of the radiation aperture of the horn feed. Therefore, the reflecting plate can be changed only by the beam of the horn feed without affecting the reflected beam of the antenna reflection surface.

In a possible implementation manner, the reflecting plate and the horn feed are connected by a welding or bonding process.

In a possible implementation manner, the reflection plate is integrally formed with the horn feed.

In a possible implementation, both the horn feed and the reflector are made of a metal material.

In a possible implementation manner, the shape of the horn feed is a prismatic structure or a cylindrical structure.

In a possible implementation manner, the shape of the reflecting plate may be a rectangular, triangular, trapezoidal, inverted trapezoidal, or semi-elliptical structure.

In a possible implementation manner, the horn feed is formed by a plurality of small-diameter horn feed arrays.

In a possible implementation manner, the horn feed is a single-mode horn feed or a dual-mode horn feed.

In a possible implementation manner, the antenna feed structure includes a first horn feed, a second horn feed, and a third horn feed that are arranged side by side in parallel with the normal direction of the feed, and the second horn feed is located at the first horn feed. Between the source and the third horn feed, the first horn feed has a first reflecting plate on the side far from the second horn feed, and the third horn feed has a diameter far away from the second horn feed. A second reflecting plate is provided on the side. When this structure is used for beam scanning, it can achieve high-gain full coverage of the beam in the spatial range, and can increase the antenna gain corresponding to the two feeds in the multi-feed antenna system.

In a possible implementation manner, the angle between the first reflection plate and the feed normal direction of the first horn feed is greater than 0 degrees and less than 45 degrees, and the second reflection plate and the feed normal direction of the third horn feed are The included angle is greater than 0 degrees and less than 45 degrees. Thereby, a more obvious beam deflection effect can be obtained.

In a possible implementation manner, an included angle between the first reflecting plate and the feed normal direction of the first horn feed is equal to an included angle between the second reflecting plate and the feed normal direction of the third horn feed. Therefore, the first reflecting plate and the second reflecting plate can be symmetrically disposed with respect to the second speaker feed, so that the gains of the first speaker feed and the third speaker feed can be the same.

In a possible implementation manner, an included angle between the first reflection plate and the feed normal direction of the first horn feed is 20 degrees.

In a possible implementation manner, a first auxiliary reflecting plate is provided on one side or two sides of the first reflecting plate, and a second auxiliary reflecting plate is provided on one side or two sides of the second reflecting plate. . As a result, the auxiliary reflector can also change the direction of electromagnetic wave propagation in the near-field area of the antenna outside the radiating aperture of the horn feed, which can further increase the antenna gain corresponding to the feed on both sides.

In a possible implementation manner, the antenna feed structure includes a main horn feed and four secondary horn feeds arranged around the main horn feed. The main horn feed is used to transmit electromagnetic signals, and the four secondary horn feeds are used for Detect the deflection angle of the antenna. The feed normal direction of the main horn feed is parallel to the feed normal direction of the four sub horn feeds. Source reflection board. Therefore, the receiving gain of the secondary horn feed in the direction of maximum gain can be increased and the resolvable range of detection can be widened, thereby improving the accuracy and sensitivity of the antenna detection function.

In a possible implementation manner, the secondary feed reflection plate is parallel to the feed normal direction of the main horn feed.

In a possible implementation manner, along the feed normal direction of the main horn feed, the radiation aperture end face of the secondary horn feed is lower than the radiation aperture end face of the main horn feed. Therefore, the phase center of the secondary horn feed can be brought closer to the phase center of the primary horn feed, so that the received power of the secondary horn feed can be further improved.

In a possible implementation manner, the height difference between the aperture end face of the secondary horn feed and the aperture end face of the main horn feed is 1 mm. Therefore, the receiving power of the secondary horn feed can be improved without causing the primary horn feed to block the signal reception of the secondary horn feed.

In a possible implementation manner, the secondary horn feed is formed by a plurality of small-diameter horn feeds in an array in a linear direction, and the linear direction is parallel to the side wall of the primary horn feed corresponding to the secondary horn feed. Therefore, on the premise that the radiation aperture of the secondary horn feed is unchanged, the width of the secondary horn feed can be reduced, thereby reducing the distance between the phase center of the secondary horn feed and the phase center of the primary horn feed, further Improved the received power of the secondary horn feed.

In a second aspect, the present application provides an antenna including at least one reflective surface, a feeding structure, and an antenna feed structure. The antenna feed structure includes a horn feed and a reflection plate. One end of the horn feed is a radiation aperture and a radiation aperture. The opposite end is the feeding aperture. The reflecting plate is located at the radiation aperture and is located within the beam radiation range of the horn feed. The feeding structure is connected to the feeding aperture. The radiation aperture is opposite to a reflecting surface.

In the antenna provided in the embodiment of the present application, since a reflection plate is provided at the radiation aperture of the horn feed, and the reflection plate can change the direction of electromagnetic wave propagation in the near field area of the antenna outside the radiation aperture of the horn feed, so no deflection is required The horn feed can make the horn feed form a preset beam direction, and it will not increase the lateral size of the horn feed. When multiple feeds are used for scanning, it is easy to achieve full beam at half power angle in the scanning range. cover. And the speaker feed of this structure does not need to be installed obliquely, so the problem of difficult installation is solved.

In a possible implementation manner of the second aspect, the reflection surface includes a main reflection surface and a sub reflection surface opposite to each other, an antenna feed structure is disposed between the main reflection surface and the sub reflection surface, and a diameter of the horn feed is opposite to the sub reflection surface The horn feed can radiate radio frequency power from the feeding structure in the form of electromagnetic waves to the sub-reflection surface. The sub-reflection surface reflects the electromagnetic waves to the main reflection surface and is reflected by the main reflection surface to form a plane wave beam.

In a possible implementation manner of the second aspect, the antenna feed structure includes a first horn feed, a second horn feed, and a third horn feed that are parallel and arranged side by side with the normal direction of the feed, and the second horn feed is located at the Between a horn feed and a third horn feed, a first reflecting plate is provided on a side of the first horn feed far from the second horn feed, and a third horn feed is far from the second horn feed. A second reflecting plate is provided on one side of the source, and the phase center of the second horn feed coincides with the focal point of the antenna.

In a possible implementation manner of the second aspect, an angle between the first reflection plate and the feed normal direction of the first horn feed is greater than 0 degrees and less than 45 degrees, and the second reflection plate and the feed of the third horn feed The included angle in the normal direction is greater than 0 degrees and less than 45 degrees. Thereby, a more obvious beam deflection effect can be obtained.

In a possible implementation manner of the second aspect, the antenna feed structure includes a main horn feed and four secondary horn feeds arranged around the main horn feed. The main horn feed is used to transmit electromagnetic signals and the four secondary horn feeds. The source is used to detect the deflection angle of the antenna. The feed normal direction of the main horn feed is parallel to the feed normal direction of the four sub horn feeds. The diameter of the sub horn feed is set at the side far from the main horn feed. There is a secondary feed reflector, and the phase center of the main horn feed coincides with the focal point of the antenna. When the antenna feed structure provided with a reflection plate is used for direction detection, the receiving gain and resolution range of the secondary horn feed can be effectively improved, and the detection function of a multi-feed system with a detection function is improved.

In a possible implementation manner of the second aspect, along the feed normal direction of the main horn feed, the radiation aperture end face of the secondary horn feed is lower than the radiation aperture end face of the main horn feed. Therefore, the phase center of the secondary horn feed can be brought closer to the phase center of the primary horn feed, so that the received power of the secondary horn feed can be further improved.

In a possible implementation manner of the second aspect, the secondary horn feed is formed by a plurality of small-diameter horn feeds in an array in a linear direction, and the linear direction is parallel to the sidewall of the primary horn feed corresponding to the secondary horn feed.

In a third aspect, the present application provides a microwave transmission device including a microwave indoor unit, a microwave outdoor unit, and a microwave antenna connected in sequence. The microwave indoor unit is used for modulating or demodulating a signal, and the microwave outdoor unit is used for For frequency conversion and amplification, the microwave antenna is used for transmission of radio frequency analog signals in space. The microwave antenna includes at least one reflective surface, a feeding structure, and an antenna feed structure. The antenna feed structure includes a horn feed and a reflection plate. One end of the horn feed is a radiation aperture, and the other end opposite the radiation aperture is a feed aperture. The reflection plate is disposed at the radiation aperture and is located within the beam radiation range of the horn feed. One end of the feed structure is connected to the At the feeding aperture, the other end is connected to the microwave outdoor unit, and the radiation aperture is opposite to a reflecting surface.

In the microwave transmission device provided in the embodiment of the present application, a reflection plate is provided at a radiation aperture of a horn feed of a microwave antenna, and the reflection plate can change an electromagnetic wave propagation direction of an antenna near a field outside the radiation aperture of the horn feed. Therefore, it is not necessary to deflect the horn feed to make the horn feed form a preset beam direction, and it does not increase the lateral size of the horn feed. When multiple feeds are used for scanning, it is easy to achieve a half in the scanning range. Full power beam coverage. And the speaker feed of this structure does not need to be installed obliquely, so the problem of difficult installation is solved. In addition, forming the horn feed into a preset beam direction can effectively achieve gapless coverage of a high-gain beam of a microwave antenna with a scanning function, or improve the detection performance of a secondary feed of a microwave antenna with a detection function.

In a possible implementation manner of the third aspect, the microwave indoor unit is configured to modulate a baseband digital signal into an IF analog signal that can be transmitted, and the microwave outdoor unit is configured to up-convert the IF analog signal transmitted by the microwave indoor unit and After being amplified and converted into a radio frequency signal of a specific frequency, it is transmitted to a microwave antenna, which is used to transmit a radio frequency signal of a specific frequency transmitted by the microwave outdoor unit in space.

In a possible implementation manner of the third aspect, the microwave antenna is configured to receive a radio frequency signal and transmit the radio frequency signal to a microwave outdoor unit, and the microwave outdoor unit is configured to down-convert a radio frequency signal received from the microwave antenna. The signal is amplified and converted into an intermediate frequency analog signal and sent to a microwave indoor unit, which is used to demodulate and digitize the received intermediate frequency analog signal and decompose it into a digital signal.

In a possible implementation manner of the third aspect, the microwave indoor unit and the microwave outdoor unit are connected through an intermediate frequency cable.

In a possible implementation manner of the third aspect, the reflection surface includes a main reflection surface and a sub reflection surface opposite to each other, the antenna feed structure is disposed between the main reflection surface and the sub reflection surface, and the aperture of the horn feed is opposite to the sub reflection surface The horn feed can radiate radio frequency power from the feeding structure in the form of electromagnetic waves to the sub-reflection surface. The sub-reflection surface reflects the electromagnetic waves to the main reflection surface and is reflected by the main reflection surface to form a plane wave beam.

In a possible implementation manner of the third aspect, the antenna feed structure includes a first horn feed, a second horn feed, and a third horn feed arranged in parallel and side by side with the normal direction of the feed, and the second horn feed is located at the Between a horn feed and a third horn feed, a first reflecting plate is provided on a side of the first horn feed far from the second horn feed, and a third horn feed is far from the second horn feed. A second reflecting plate is provided on one side of the source, and the phase center of the second horn feed coincides with the focal point of the antenna.

In a possible implementation manner of the third aspect, the angle between the first reflection plate and the feed normal direction of the first horn feed is greater than 0 degrees and less than 45 degrees, and the second reflection plate and the feed of the third horn feed The included angle in the normal direction is greater than 0 degrees and less than 45 degrees. Thereby, a more obvious beam deflection effect can be obtained.

In a possible implementation manner of the third aspect, the antenna feed structure includes a main horn feed and four secondary horn feeds arranged around the main horn feed. The main horn feed is used to transmit electromagnetic signals and the four secondary horn feeds. The source is used to detect the deflection angle of the antenna. The feed normal direction of the main horn feed is parallel to the feed normal direction of the four sub horn feeds. The diameter of the sub horn feed is set at the side far from the main horn feed. There is a secondary feed reflector, and the phase center of the main horn feed coincides with the focal point of the antenna. When the antenna feed structure provided with a reflection plate is used for direction detection, the receiving gain and resolution range of the secondary horn feed can be effectively improved, and the detection function of a multi-feed system with a detection function is improved.

In a possible implementation manner of the third aspect, along the feed normal direction of the main horn feed, the radiation aperture end face of the secondary horn feed is lower than the radiation aperture end face of the main horn feed. Therefore, the phase center of the secondary horn feed can be brought closer to the phase center of the primary horn feed, so that the received power of the secondary horn feed can be further improved.

In a possible implementation manner of the third aspect, the secondary horn feed is formed by a plurality of small-diameter horn feeds in an array in a straight line direction, and the linear direction is parallel to the side wall of the primary horn feed corresponding to the secondary horn feed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic structural diagram of an antenna feed structure;

2 is an explanatory diagram of the irradiation angle of the feed source;

3 is a schematic structural diagram of an antenna feed structure according to an embodiment of the present application;

4 is a schematic diagram of a shape of a reflection plate in an antenna feed structure according to an embodiment of the present application;

5 is a schematic cross-sectional structure diagram of an antenna feed structure with a beam scanning function;

FIG. 6 is a diagram of an experimental result of a beam scan when a reflection plate is not provided; FIG.

FIG. 7 is a graph of a beam scanning experiment result when a reflecting plate is provided; FIG.

8 is a schematic structural diagram of an antenna feed structure having an antenna detection function;

9 is a schematic cross-sectional structure diagram of an antenna feed structure having an antenna detection function;

10 is a schematic cross-sectional structure diagram of a main horn feed in an antenna feed structure having an antenna detection function;

11 is a schematic cross-sectional structure diagram of a secondary horn feed in an antenna feed structure having an antenna detection function;

FIG. 12 is a diagram of an experimental result of antenna detection when no reflection plate is provided; FIG.

FIG. 13 is a diagram of an antenna detection experiment result when a reflecting plate is provided; FIG.

14 is a structural diagram of an antenna having a beam scanning function;

15 is a structural diagram of an antenna having an antenna detection function;

FIG. 16 is a schematic structural diagram of a microwave transmission device according to an embodiment of the present application.

Detailed ways

This embodiment of the present application relates to an antenna feed structure and an antenna. The following briefly describes the concepts involved in the foregoing embodiments:

Antenna feed: The antenna feed is the primary radiator (horn or vibrator) of the main and auxiliary reflective surfaces of the excitation surface antenna, referred to as the feed. It is an important device that determines the electrical characteristics and frequency band of the antenna. Its role is to radiate the RF power from the feeder to the reflective surface or lens in the form of electromagnetic waves, so that it produces a suitable field distribution on the aperture to form the required sharp beam or shaped beam; at the same time, the reflective surface Or the power of the lens and other edges leaking out as small as possible, in order to achieve the highest possible gain.

Plane antenna: Plane antenna refers to an antenna with a primary feed and a secondary radiation field formed by a reflective surface.

Antenna gain: The ratio of the power density of the signal generated by the actual antenna and the ideal radiating unit at the same point in space under the condition of equal input power. It quantitatively describes the degree to which an antenna concentrates input power to radiate.

Phase center of the antenna: After the electromagnetic wave radiated from the antenna leaves a certain distance from the antenna, its isophase plane will be approximately a spherical surface, and the center of the spherical surface is the equivalent phase center of the antenna.

Cassegrain antenna: consists of three parts, namely the main reflector, the sub-reflector and the radiation source. The main reflector is a rotating parabola, and the secondary reflecting surface is a rotating hyperbola. Structurally, one focal point of the hyperbola coincides with the focal point of the parabola, the focal axis of the hyperbola coincides with the focal axis of the parabola, and the radiation source is located at the other focal point of the hyperbola, as shown in the figure below. It is a reflection of electromagnetic waves emitted by a radiation source by a sub-reflector. The electromagnetic waves are reflected on the main reflector, and then reflected by the main reflector to obtain a plane wave beam in the corresponding direction to achieve directional emission.

Antenna near-field area and far-field area: The field surrounding the antenna can be divided into two main areas. The area close to the antenna is called the antenna near-field area or Fresnel zone, and the distance from the antenna is called the antenna distance. Field or Franchhofa. The boundary line radius r of the antenna near-field region and the antenna far-field region can satisfy the following relationship: k × r = 10, where k is a phase constant.

Feed irradiation angle: as shown in FIG. 2, that is, the angle α of the beam at the opposite edge of the planar antenna b irradiated by the horn feed a.

The radiating caliber of a horn feed refers to a port with a large area of the horn feed. The radiating caliber is used to radiate electromagnetic waves to space or receive electromagnetic wave signals in space.

The feeding aperture of the horn feed refers to a port diameter with a relatively small area opposite to the radiating aperture. The feeding aperture is used to connect with the feeding structure to transmit electromagnetic wave signals to the feeding structure.

As shown in FIG. 3, an embodiment of the present application provides an antenna feed structure, including a horn feed 1 and a reflection plate 2. The reflection plate 2 is disposed at the radiation aperture 11 of the horn feed 1, and the reflection plate 2 can change the horn The direction of electromagnetic wave propagation in the near-field area of the antenna outside the radiation aperture 11 of the feed source 1 causes the horn feed source 1 to form a preset beam direction.

In the antenna feed structure provided in the embodiment of the present application, since a reflection plate 2 is provided at the radiation aperture 11 of the horn feed 1, and the reflection plate 2 can change the electromagnetic waves in the near field of the antenna outside the radiation aperture 11 of the horn feed 1 The direction of propagation, so that the horn feed 1 can be formed into a preset beam direction without deflecting the horn feed 1, and the lateral size of the horn feed 1 is not increased. When multiple feeds are used for scanning, It is easy to achieve full coverage of the beam at half power angle in the scanning range. In addition, the speaker feed 1 of this structure does not need to be installed obliquely, thereby solving the problem that the installation of the oblique is difficult.

It should be noted that the preset beam pointing may be a direction that requires a speaker feed source to be pointed in an actual application scenario. For example, in an antenna with a multi-feed structure having a scanning function, the preset beam pointing may refer to a beam pointing of a feed in the middle; in an antenna with a multi-feed structure having a detecting function, the preset beam pointing may May refer to the maximum gain direction of the main feed used to transmit the signal.

Specifically, the reflection plate 2 may be disposed within a range of a feed irradiation angle of the horn feed 1. Therefore, when the antenna feed structure is applied to a surface antenna, the reflecting plate 2 can be used to change the beam direction when the horn feed 1 is irradiated to the surface antenna, thereby improving the performance of the surface antenna.

As shown in FIG. 3, the angle φ between the reflection plate 2 and the feed normal direction X of the horn feed 1 can be selected to be greater than or equal to 0 degrees and less than 45 degrees. If φ is less than 0 degrees, the effect of changing the beam direction will be weaker. If φ is greater than or equal to 45 degrees, more beams will be reflected back into the horn feed 1, thereby reducing the radiation intensity of the horn feed 1. Therefore, setting the value range of φ to be greater than or equal to 0 degrees and less than 45 degrees can not only make the effect of changing the beam pointing obvious, but also not have a great impact on the radiation intensity of the horn feed 1.

It should be noted that the direction of the feed normal is the direction perpendicular to the plane where the feed aperture is located and pointing to the feed beam (that is, the X direction in FIG. 3 and FIG. 5).

In order to prevent the loaded reflector plate 2 from blocking the antenna beam due to being too long, the reflector plate 2 can change the direction of the feed beam in a non-far-field region, that is, the reflector plate 2 is entirely located in the near-field area of the antenna. As shown in Figure 3, the length R1 of the reflecting plate 2 must meet the non-far-field condition: k × r≤10, where k is the phase constant and k = 2π / λ; r is the distance from a point in the near-field region to the phase center. The distance, r can be approximated as Rh (that is, the length of the reflection plate 2 in the direction of the feed normal line), and Rh = R1 × cosφ. After a simple derivation, it can be obtained that the length R1 of the reflection plate 2 can satisfy: R1≤5λ / (π × cosφ).

In a direction parallel to the end face where the radiation aperture 11 of the horn feed 1 is located, the maximum width Rw of the reflection plate 2 is less than or equal to the width W of the radiation aperture 11 of the horn feed 1. Therefore, the reflecting plate 2 can be changed only the beam of the horn feed 1 without affecting the reflected beam of the antenna reflection surface.

The connection between the reflective plate 2 and the horn feed 1 can be completed by welding or bonding, or it can be manufactured by an integral molding process. The horn feed 1 and the reflection plate 2 may be made of a metal material, such as aluminum, copper, iron, silver and the like.

In a possible implementation manner, the specific structures of the reflection plate 2 and the horn feed 1 may be shown in FIG. 3. The shape of the horn feed 1 is a quadrangular prism structure, and a conical horn-shaped cavity is formed inside the quadrangular prism structure. The reflecting plate 2 is connected to the end surface of the quadrangular prism structure provided with the radiation aperture 11, and the reflecting plate 2 can be connected to the edge position of the end surface.

It should be noted that the external shape of the horn feed 1 is not limited to a quadrangular prism structure, but may also be a prism structure such as a triangular prism, a pentaprism, or a cylindrical structure or a horn-shaped structure. The cavity structure inside the horn feed 1 is not limited to a conical horn structure, and may also be a pyramid horn structure. The shape of the reflecting plate 2 may be a rectangular, triangular, trapezoidal, inverted trapezoidal or semi-elliptical structure, and may also be a combination of a rectangular and semi-circular structure as shown in FIG. 4. The structural form of the horn feed 1 is not limited to a single-diameter horn feed 1, and one horn feed 1 may also be formed by an array of multiple small-diameter horn feeds 1. The horn feed 1 can be a single-mode horn feed 1 or a dual-mode horn feed 1.

In a specific embodiment of the present application, as shown in FIG. 5, the antenna feed structure includes three horn feeds, and the normal directions of the feeds of the three horn feeds are parallel and arranged side by side, which are the first horns, respectively. Feed 1a, second horn feed 1b, and third horn feed 1c, the second horn feed 1b is located between the first horn feed 1a and the third horn feed 1c, where the first horn feed 1a A first reflecting plate 2a is provided on the side of the radiation aperture away from the second horn feed 1b, and a second reflection plate 2b is provided on the side of the radiation aperture of the third horn feed 1c away from the second horn feed 1b. The first reflecting plate 2a can deflect the beam of the first horn feed 1a toward the beam of the second horn feed 1b, and make the equivalent phase center of the first horn feed 1a equal to that of the second horn feed 1b. The effective phase center is shifted; the second reflecting plate 2b can deflect the beam pointing of the third horn feed 1c toward the beam pointing of the second horn feed 1b, and make the equivalent phase center of the third horn feed 1c toward the second The equivalent phase center of the horn feed 1b is shifted. Therefore, during beam scanning, high-gain full coverage of the beam in the spatial range can be achieved, and the antenna gains corresponding to the two feeds in the multi-feed antenna system can be improved.

In order to facilitate the description of the above beam scanning effect provided by the reflection plate, the antenna feed structure with the reflection plate and the antenna feed structure without the reflection plate in FIG. 5 can be applied to the Cassegrain antenna for beams, respectively. Scanning simulation. As shown in FIG. 14, when the feed is installed, the antenna feed structure 300 is installed between the main reflection surface 101 and the sub-reflection surface 102 of the Cassegrain antenna, and the phase center of the second horn feed 1b and the jam The focal points of the Glen antennas coincide. Specifically, as shown in FIG. 5, the structural parameters of the horn feed are as follows: the diameter of the horn feed radiation diameter D1 = 6mm, the diameter of the horn feed feed diameter D0 = 2.65mm, and the horn feed radiation diameter along the feed method The length in the line direction is L2 = 10mm, the length of the horn feed transition section L1 = 3.1mm, and the length of the horn feed electrical waveguide section L0 = 8mm. The structural parameters of the reflecting plate are as follows: the width of the reflecting plate is Rw = 6mm, the length of the reflecting plate is R1 = 5.8mm, the thickness of the reflecting plate is t = 0.25mm, and the angle between the reflecting plate and the direction of the feed normal is φ = 20 degrees. The structural parameters of the Cassegrain antenna are as follows: the diameter of the main reflection surface is 150mm, the diameter of the sub-reflection surface is 23mm, the irradiation angle of the feed is 42 degrees, and the focal diameter ratio of the Cassegrain antenna is 0.385.

FIG. 6 is a graph of a beam scanning experiment result when a reflecting plate is not provided, and FIG. 7 is a graph of a beam scanning experiment result when a reflecting plate is provided. Comparing the experimental results of Fig. 6 and Fig. 7, it can be seen that at 35.2 dBi in Fig. 6, between the beam of the first horn feed 1a and the beam of the second horn feed 1b, and the beam of the third horn feed 1c and the second horn There is a beam interval of 2 degrees between the feed 1b beams, so full beam coverage cannot be achieved in high gain areas. In Fig. 7, at 35.2dBi, full beam coverage of ± 3.2 degrees can be achieved, so that high-gain beam full coverage can be achieved in the spatial range. And the antenna feed structure after the reflection plate is provided is compared with the antenna feed structure without the reflection plate, as shown in FIG. 6 and FIG. 7, the beams corresponding to the first speaker feed 1a and the third speaker feed 1c The gain has been increased from 37.2dBi to 38.7dBi, which improves the antenna gain corresponding to the two feeds in the multi-feed antenna system.

It should be noted that the antenna feed structure shown in FIG. 5 is only a basic feed implementation structure. It is conceivable that in order to obtain a larger scanning range, the feed structure may also include more speaker feeds. For example, four, five, six speaker feeds arranged side by side, etc. are not limited here.

In order to obtain a more obvious beam deflection effect, the angle between the first reflection plate 2a and the feed normal direction of the first horn feed 1a can be set to be greater than 0 degrees and less than 45 degrees, and the second reflection plate 2b The included angle with the direction of the feed normal of the third horn feed 1c is set to be greater than 0 degrees and less than 45 degrees.

In a possible implementation manner, an included angle between the first reflection plate 2a and the feed normal direction of the first horn feed 1a may be equal to the feed normal of the second reflection plate 2b and the third horn feed 1c. The angle of the direction. Thereby, the first reflecting plate 2a and the second reflecting plate 2b can be symmetrically disposed with respect to the second speaker feed 1b, so that the gains of the first speaker feed 1a and the third speaker feed 1c can be the same.

The number of reflection plates is not limited to one, and a first auxiliary reflection plate may be provided on an adjacent side or two sides of the first reflection plate 2a. Similarly, on the adjacent side of the second reflection plate 2b Or a second auxiliary reflecting plate may be provided on two adjacent sides. Therefore, the auxiliary reflecting plate can also change the direction of electromagnetic wave propagation in the near-field area of the antenna outside the radiating aperture of the horn feed, thereby further improving the antenna gain corresponding to the feed on both sides.

During the daily use of the antenna, due to the interference of external factors (such as wind, rain, etc.), its angle may be deflected, which will cause the antenna's pointing to deviate from the predetermined angle. Therefore, in order to ensure that the antenna is always at the predetermined angle, the antenna must have a detection function That is, a detection feed is provided on the antenna, specifically, four secondary feeds are respectively arranged around the main feed, and the deflection angle of the antenna can be obtained through the received signal power comparison and algorithm judgment of the four secondary feeds, and then the servo is used. The system controls the deflection of the antenna to correct the beam. When the detection function is implemented, due to the larger diameter of the horn feed, the secondary feed is farther away from the primary feed in the middle. The beam direction of the secondary feed is farther away from the direction of the maximum received power, resulting in a secondary feed. The receive gain and resolvable range are both small.

In order to solve the above problem, a horn feed structure provided with a reflecting plate in the present application may be adopted. Specifically, as shown in FIG. 8, the antenna feed includes a main horn feed 1a ′ and four horns provided around the main horn feed 1a ′. One secondary speaker feed (1b ', 1c', 1d ', 1e'), the primary speaker feed 1a 'is used to transmit electromagnetic signals, and four secondary speaker feeds (1b', 1c ', 1d', 1e ') For detecting the deflection angle of the antenna, the feed normal direction of the main horn feed 1a 'is parallel to the feed normal directions of the four secondary horn feeds (1b', 1c ', 1d', 1e '), and the secondary horn A side of the feed source (1b ', 1c', 1d ', 1e') far from the main speaker feed 1a 'is provided with a secondary feed reflection plate 2'. Thus, the secondary feed reflection plate 2 'can direct the beams of the four secondary horn feeds (1b', 1c ', 1d', 1e ') to deflect toward the main horn feed 1a'. The beam of the source 1a 'is directed to the maximum gain direction, so that the receiving gain of the secondary speaker feed (1b', 1c ', 1d', 1e ') in the maximum gain direction can be increased and the detectable range can be widened. This improves the accuracy and sensitivity of the antenna detection function.

In order to facilitate the description of the above detection effect provided by the reflection plate, the antenna feed structure with the reflection plate and the antenna feed structure without the reflection plate in FIG. 8 can be applied to the Cassegrain antenna for antenna detection, respectively. Functional simulation experiment. As shown in FIG. 15, when the feed is installed, the antenna feed structure 300 is installed between the main reflection surface 101 and the sub-reflection surface 102 of the Cassegrain antenna, and the phase center of the main horn feed 1a ′ and the jam The focal points of the Glen antennas coincide. The primary speaker feed 1a 'is a dual-mode speaker feed, and the secondary speaker feed is a dual-mode speaker feed of two small-diameter speaker feed arrays. Specifically, as shown in FIG. 9, FIG. 10, and FIG. 11, the structural parameters of the feed are as follows: the diameter D0 of the feed aperture of the main horn feed 1a ′ is 2.65 mm, and the diameter D1 of the radiation aperture of the main horn feed 1a ′ = 6mm, the length of the main horn feed 1a 'electrical waveguide section L0 = 8mm, the length of the main horn feed 1a' transition section L1 = 3.1mm, the length of the main horn feed 1a 'radiating section L2 = 10mm, and the main horn feed 1a' Wall thickness t = 0.5mm, the diameter of the feed diameter of the small-diameter horn feed of the secondary horn feed D2 = 2.6mm, the diameter of the radiation diameter of the small-diameter horn feed D3 = 2.7mm, the power of the small-diameter horn feed The length of the waveguide section L3 = 4mm, the length of the transition section of the small-diameter horn feed L4 = 3mm, the length of the radiation section of the small-diameter horn feed L5 = 13.1mm, the distance between the two small-diameter horn feeds t1 = 0.5mm, the main The height difference between the speaker feed 1a 'and the secondary speaker feed is dh = 1mm; the structural parameters of the reflector are as follows: the width of the reflector Rw = 6.4mm, the length of the reflector R1 = 5.8mm, and the thickness of the reflector is 0.5mm, The angle between the reflector and the direction of the feed normal is 0 degrees. The structural parameters of the Cassegrain antenna are as follows: the diameter of the main reflection surface is 660mm, the diameter of the secondary reflection surface is 100mm, the feed angle of the feed is 42 degrees, and the focal diameter ratio of the Cassegrain antenna is 0.385.

FIG. 12 is an experimental result diagram of the detection function when the feed structure is not provided with a reflective plate; FIG. 13 is an experimental result diagram of the detection function when the feed structure is provided with a reflective plate. It should be noted that FIG. 12 and FIG. 13 use the main horn feed 1a ′ and the opposite sub-horn feeds (1b ′ and 1d ′) as examples to conduct experiments, and the other two horn feeds. The experimental results of (1c 'and 1e') are similar to those of Figs. 12 and 13. Among them, the gain of the secondary horn feed is the receiving gain of the secondary horn feed in the maximum gain direction of the primary horn feed 1a '(that is, the 0 degree direction in FIG. 12 and FIG. 13), and the distinguishable range is two secondary horn feeds. The area where the difference between the source receiving gains changes monotonically. As can be seen from FIG. 12, when the feed structure is not provided with a reflective plate, the gain of the secondary horn feed is 27 dBi, and the resolvable range is ± 0.055 degrees. As can be seen from FIG. 13, when the feed structure is provided with a reflective plate, the gain of the sub-horn feed is 36.9 dBi, and the resolvable range is ± 0.1 degree. Comparing the two sets of data, it can be seen that the gain of the secondary horn feed is increased by 9.9 dBi, and the resolvable range is widened by 82%. It can be seen that the use of a secondary speaker feed structure provided with a reflection plate can effectively improve the receiving gain and resolution range of the secondary speaker feed, and improve the detection function of a multi-feed system with a detection function.

In the embodiment shown in FIG. 9, in order to facilitate the manufacturing process, the secondary feed reflection plate 2 ′ is arranged parallel to the feed normal direction of the main horn feed 1 a ′. It is conceivable that, in order to obtain greater received power, the angle between the secondary feed reflector 2 'and the feed normal direction of the main horn feed 1a' can be increased.

In order to further increase the receiving power of the secondary horn feed, as shown in FIG. 9, along the feed normal direction X of the primary horn feed 1a ′, the radiation aperture end face of the secondary horn feed is lower than the radiation of the primary horn feed 1a ′. Caliber end face. Therefore, compared with the plan where the radiating end faces of the primary and secondary horn feeds are flush, this structure can bring the phase center of the secondary horn feed closer to the phase center of the primary horn feed 1a ', thereby further improving the secondary horn Received power of the feed.

In order to further reduce the distance between the phase center of the secondary horn feed and the phase center of the primary horn feed 1a ', the secondary horn feed may be formed by a plurality of small-diameter horn feeds in an array in a linear direction, and the linear direction and the secondary horn The side wall of the main horn feed 1a 'corresponding to the feed is parallel. As shown in FIG. 8, the four secondary speaker feeds all use 1 × 2 array speaker feeds, and the array direction of the two small-diameter speaker feeds is parallel to the side wall of the primary speaker feed 1a ′. Therefore, as shown in FIG. 9, under the premise that the radiation diameter of the secondary horn feed is unchanged, the width B of the secondary horn feed can be reduced, so that the phase center of the secondary horn feed and the primary horn feed 1a ′ are reduced. The distance between the phase centers is reduced, which further improves the received power of the secondary horn feed.

This application also provides an antenna, as shown in FIGS. 14 and 15, including at least one reflective surface 100, a feeding structure 200, and an antenna feed structure 300. The antenna feed structure 300 may include a speaker feed as shown in FIG. 3. Source 1 and reflector 2, one end of horn feed 1 is radiation aperture 11, and the other end opposite to radiation aperture 11 is the feed aperture. Reflector 2 is located at radiation aperture 11 and located in the beam radiation range of horn feed 1. Here, the feeding structure 200 is connected to the feeding aperture, and the radiation aperture 11 is opposite to a reflecting surface 100.

In the antenna provided in the embodiment of the present application, since a reflection plate 2 is provided at the radiation aperture 11 of the horn feed 1, and the reflection plate 2 can change the electromagnetic wave propagation direction of the antenna near the field outside the radiation aperture 11 of the horn feed 1, Therefore, the horn feed 1 can be formed into a preset beam direction without deflecting the horn feed 1, and the lateral size of the horn feed 1 is not increased. When multiple feeds are used for scanning, the scanning range is within the scanning range. It is easy to achieve full beam coverage at half power angle. In addition, the speaker feed 1 of this structure does not need to be installed obliquely, thereby solving the problem that the installation of the oblique is difficult.

The reflecting surface 100 is configured to reflect the electromagnetic waves emitted by the antenna feed structure 300 to form a planar beam. The reflecting surface 100 may be a structure such as a convex convex hyperbola or a paraboloid.

The feeding structure 200 is a transmission device for transmitting electromagnetic waves. The feeding structure 200 may be a structure such as a feeding waveguide metal tube, a feeding coaxial cable, a feeding microstrip line, and the like.

Specifically, the antenna may be a Cassegrain antenna. As shown in FIGS. 14 and 15, the reflection surface of the Cassegrain antenna includes a main reflection surface 101 and a sub reflection surface 102 opposite to each other. The antenna feed structure is disposed on the main Between the reflective surface 101 and the sub-reflective surface 102, the diameter of the horn feed is opposite to the sub-reflective surface 102. The horn feed can radiate radio frequency power from the feeding structure to the sub-reflective surface 102 in the form of electromagnetic waves. The sub-reflective surface 102 The electromagnetic wave is reflected to the main reflection surface 101 and reflected by the main reflection surface 101 to form a plane wave beam.

As shown in FIG. 14, when the antenna has a beam scanning function, the antenna feed structure may be as shown in FIG. 5, including a first speaker feed 1a, a second speaker feed 1b, and The third horn feed 1c and the second horn feed 1b are located between the first horn feed 1a and the third horn feed 1c. The caliber of the first horn feed 1a is located on the side far from the second horn feed 1b. There is a first reflection plate 2a, a second reflection plate 2b is provided on the side of the aperture of the third horn feed 1c far from the second horn feed 1b, and the phase center of the second horn feed 1b coincides with the focal point of the antenna. The first reflecting plate 2a can deflect the beam of the first horn feed 1a toward the beam of the second horn feed 1b, and make the equivalent phase center of the first horn feed 1a equal to that of the second horn feed 1b. The effective phase center is shifted; the second reflecting plate 2b can deflect the beam pointing of the third horn feed 1c toward the beam pointing of the second horn feed 1b, and make the equivalent phase center of the third horn feed 1c toward the second The equivalent phase center of the horn feed 1b is shifted. Therefore, during beam scanning, high-gain full coverage of the beam in the spatial range can be achieved, and the antenna gains corresponding to the two feeds in the multi-feed antenna system can be improved.

As shown in FIG. 15, when the antenna has a direction detection function, the antenna feed structure may be as shown in FIG. 8, including the main horn feed 1 a ′ and four secondary horn feeds (4) provided around the main horn feed 1 a ′. 1b ', 1c', 1d ', 1e'), the main horn feed 1a 'is used to transmit electromagnetic signals, and the four secondary horn feeds (1b', 1c ', 1d', 1e ') are used to detect antenna deflection Angle, the feed normal direction of the main horn feed 1a 'is parallel to the feed normal direction of the four secondary horn feeds (1b', 1c ', 1d', 1e '), and the secondary horn feed (1b', 1c ', 1d', 1e ') are provided at the side far from the main speaker feed 1a', and a secondary feed reflector 2 'is provided. The phase center of the main speaker feed 1a' coincides with the focal point of the antenna. When the antenna feed structure provided with a reflection plate is used for direction detection, the receiving gain and resolution range of the secondary horn feed (1b ', 1c', 1d ', 1e') can be effectively improved, and the multi-detector function can be improved. Detection function of the feed system.

The present application also provides a microwave transmission device, as shown in FIG. 16, including a microwave indoor unit 400, a microwave outdoor unit 500, and a microwave antenna 600 connected in this order. The microwave indoor unit 400 is used for modulating or demodulating a signal. The microwave outdoor unit 500 is used for frequency conversion and amplification of signals. The microwave antenna 600 is used for transmission of radio frequency analog signals in space. The structure of the microwave antenna 600 may be as shown in FIGS. 14 and 15 and includes at least one reflective surface. 100. Feed structure 200 and antenna feed structure 300. The structure of the antenna feed can be as shown in FIG. 3, including the horn feed 1 and the reflection plate 2. One end of the horn feed 1 is a radiation aperture 11 and a radiation aperture 11 The opposite end is the feeding aperture. The reflecting plate 2 is disposed at the radiation aperture 11 and is located within the beam radiation range of the horn feed 1. One end of the feeding structure 200 is connected to the feeding aperture, and the other end is connected to the microwave outdoor unit 500. Connected, the radiation aperture 11 is opposite to one of the reflective surfaces 100.

In the microwave transmission device provided in the embodiment of the present application, since a reflection plate is provided at the radiation aperture of the horn feed of the microwave antenna 600, and the reflection plate can change the electromagnetic wave propagation direction of the antenna near field outside the radiation aperture of the horn feed, Therefore, the horn feed can be formed into a preset beam direction without deflecting the horn feed, and the lateral size of the horn feed is not increased. When multiple feeds are used for scanning, it is easy to achieve within the scanning range. Full coverage at half power angle. And the speaker feed of this structure does not need to be installed obliquely, so the problem of difficult installation is solved. In addition, forming the horn feed into a predetermined beam direction can effectively achieve gapless coverage of the high-gain beam of the microwave antenna 600 with a scanning function, or improve the secondary feed detection performance of the microwave antenna 600 with a detection function.

When the microwave transmission device is a signal transmitting device, the microwave indoor unit 400 is used to modulate the baseband digital signal into an IF analog signal that can be transmitted, and the microwave outdoor unit 500 is used to up-convert and amplify the IF analog signal transmitted by the microwave indoor unit 400. After being converted into a radio frequency signal of a specific frequency, the radio frequency signal is transmitted to the microwave antenna 600, and the microwave antenna 600 is configured to transmit a radio frequency signal of a specific frequency transmitted by the microwave outdoor unit 500 in space.

When the microwave transmission device is a signal receiving device, the microwave antenna 600 is configured to receive a radio frequency signal and transmit the radio frequency signal to a microwave outdoor unit 500. The microwave outdoor unit 500 is configured to receive a radio frequency received from the microwave antenna 600. The signal is down-converted and amplified, converted into an intermediate frequency analog signal and sent to the microwave indoor unit 400, which is used to demodulate and digitize the received intermediate frequency analog signal and decompose it into a digital signal.

Since an intermediate frequency analog signal is transmitted between the microwave indoor unit 400 and the microwave outdoor unit 500, as shown in FIG. 16, the microwave indoor unit 400 and the microwave outdoor unit 500 may be connected through an intermediate frequency cable 700.

The above are only specific embodiments of the present invention, but the scope of protection of the present invention is not limited to this. Any person skilled in the art can easily think of changes or replacements within the technical scope disclosed by the present invention. It should be covered by the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

An antenna feed structure is characterized in that it includes a horn feed and a reflecting plate, the reflecting plate is arranged at the radiation aperture of the horn feed, and the reflecting plate can change the antenna outside the aperture of the horn feed. The direction of electromagnetic wave propagation in the field area makes the horn feed form a preset beam direction.
The antenna feed structure according to claim 1, wherein the reflection plate is disposed within a range of an irradiation angle of the feed of the horn feed.
The antenna feed structure according to claim 1 or 2, wherein an included angle between the reflection plate and a feed normal direction of the horn feed is greater than or equal to 0 degrees and less than 45 degrees.
The antenna feed structure according to any one of claims 1 to 3, wherein the entire reflection plate is located in the near-field area of the antenna.
The antenna feed structure according to any one of claims 1 to 4, characterized in that, in a direction parallel to an end face where a radiation aperture of the horn feed is located, a maximum width of the reflecting plate is less than or equal to the The width of the radiation aperture of the horn feed.
The antenna feed structure according to any one of claims 1 to 5, wherein the antenna feed structure includes a first horn feed and a second horn feed arranged in parallel and side by side with a normal direction of the feed. And a third speaker feed, the second speaker feed is located between the first speaker feed and the third speaker feed, and the aperture of the first speaker feed is far from the second speaker feed A first reflection plate is provided on one side of the source, and a second reflection plate is provided on the side of the third horn feed source that is far from the second horn feed source.
The antenna feed structure according to claim 6, wherein an included angle between the first reflection plate and a feed normal direction of the first horn feed is greater than 0 degrees and less than 45 degrees, and the first The included angle between the two reflection plates and the feed normal direction of the third horn feed is greater than 0 degrees and less than 45 degrees.
The antenna feed structure according to claim 6 or 7, wherein a first auxiliary reflection plate is provided on one side or two sides of the first reflection plate, and a phase of the second reflection plate is A second auxiliary reflection plate is provided on one side or two sides.
The antenna feed structure according to any one of claims 1 to 5, wherein the antenna feed structure includes a main speaker feed and four secondary speaker feeds arranged around the main speaker feed The main horn feed is used to transmit electromagnetic signals, the four horn feeds are used to detect the deflection angle of the antenna, the feed normal direction of the main horn feed and the four horn feeds The normal direction of the feed source is parallel, and the side of the secondary horn feed is far away from the primary horn feed side, and a secondary feed reflection plate is provided.
The antenna feed structure according to claim 9, wherein the secondary feed reflection plate is parallel to the feed normal direction of the main horn feed.
The antenna feed structure according to claim 9 or 10, characterized in that, along the feed normal direction of the main horn feed, the radiation aperture end face of the secondary horn feed is lower than the main horn feed Radiation caliber end face.
The antenna feed structure according to any one of claims 9 to 11, wherein the secondary horn feed is formed by a plurality of small-diameter horn feeds in an array in a linear direction, and the linear direction and the secondary The side wall of the main horn feed corresponding to the horn feed is parallel.
An antenna is characterized by comprising at least one reflecting surface, a feeding structure, and an antenna feed structure. The antenna feed structure includes a horn feed and a reflection plate. One end of the horn feed is a radiation aperture, and The opposite end of the radiating aperture is a feeding aperture, the reflecting plate is disposed at the radiating aperture and is located within a beam radiation range of a horn feed, and the feeding structure is connected to the feeding aperture. The radiation aperture is opposite to one of the reflecting surfaces.
The antenna according to claim 13, wherein the reflection surface comprises a main reflection surface and a sub reflection surface which are oppositely disposed, and the antenna feed structure is disposed between the main reflection surface and the sub reflection surface, and The aperture of the horn feed is opposite to the secondary reflecting surface. The horn feed can radiate radio frequency power from the feeding structure to the secondary reflecting surface in the form of electromagnetic waves, and the secondary reflecting surface reflects the electromagnetic waves. A plane wave beam is formed by reflecting to the main reflection surface.
The antenna according to claim 14, wherein the antenna feed structure comprises a first horn feed, a second horn feed, and a third horn feed arranged in parallel and side by side with a normal direction of the feed, and the A second horn feed is located between the first horn feed and the third horn feed, and a first reflection is provided on a side of the first horn feed that is far from the second horn feed. Plate, a second reflecting plate is provided on the side of the third horn feed that is far from the second horn feed, and the phase center of the second horn feed coincides with the focal point of the antenna.
The antenna according to claim 15, wherein an included angle between the first reflection plate and a feed normal direction of the first horn feed is greater than 0 degrees and less than 45 degrees, and the second reflection plate The included angle with the feed normal direction of the third horn feed is greater than 0 degrees and less than 45 degrees.
The antenna according to claim 14, wherein the antenna feed structure comprises a main horn feed and four secondary horn feeds arranged around the main horn feed, and the main horn feed is used for Transmission of electromagnetic signals. The four horn feeds are used to detect the deflection angle of the antenna. The feed normal directions of the main horn feeds are parallel to the feed normal directions of the four horn feeds. A secondary-feed reflector is provided on the side of the secondary horn feed that is far from the primary horn feed, and the phase center of the primary horn feed coincides with the focal point of the antenna.
The antenna according to claim 17, wherein the aperture end face of the secondary horn feed is lower than the aperture end face of the main horn feed along the feed normal direction of the main horn feed.
The antenna according to claim 17 or 18, wherein the secondary horn feed is formed by a plurality of small-diameter horn feeds in an array in a linear direction, and the linear direction corresponds to the secondary horn feed. The side walls of the main horn feed are parallel.
A microwave transmission device is characterized by comprising a microwave indoor unit, a microwave outdoor unit, and a microwave antenna connected in sequence. The microwave indoor unit is used for modulating or demodulating a signal, and the microwave outdoor unit is used for frequency conversion and signal conversion. Amplified, the microwave antenna is used for transmission of radio frequency analog signals in space. The microwave antenna includes at least one reflective surface, a feeding structure, and an antenna feed structure. The antenna feed structure includes a horn feed and a reflection plate. One end of the source is a radiation caliber, and the other end opposite to the radiation caliber is a feeding caliber. The reflecting plate is disposed at the radiation caliber and is located within the beam radiation range of the horn feed. One end of the feeding structure is connected to the feeding caliber. At the aperture, the other end is connected to the microwave outdoor unit, and the radiation aperture is opposite to one of the reflecting surfaces.
The microwave transmission device according to claim 20, wherein the microwave indoor unit is configured to modulate a baseband digital signal into an IF analog signal that can be transmitted, and the microwave outdoor unit is used to IF analog transmitted by the microwave indoor unit. After the signal is up-converted and amplified, and converted into a radio frequency signal of a specific frequency, the signal is transmitted to a microwave antenna, and the microwave antenna is used to transmit a radio frequency signal of a specific frequency transmitted by the microwave outdoor unit in space.
The microwave transmission device according to claim 20, wherein the microwave antenna is configured to receive a radio frequency signal and transmit the radio frequency signal to a microwave outdoor unit, and the microwave outdoor unit is configured to receive a signal received from the microwave antenna. The radio frequency signal is down-converted and amplified, converted into an intermediate frequency analog signal and sent to a microwave indoor unit, which is used to demodulate and digitize the received intermediate frequency analog signal and decompose it into a digital signal.