CN218123722U

CN218123722U - 6 to 40GHz four-ridge horn antenna

Info

Publication number: CN218123722U
Application number: CN202222048844.6U
Authority: CN
Inventors: 黄鸿涛; 王合义; 马凤霞
Original assignee: Nanjing Xinweilian Electronic Technology Co ltd
Current assignee: Nanjing Xinweilian Electronic Technology Co ltd
Priority date: 2021-12-31
Filing date: 2022-08-05
Publication date: 2022-12-23
Anticipated expiration: 2032-08-05

Abstract

The invention provides a 6 to 40GHz four-ridge horn antenna which comprises a rectangular horn, a coaxial four-ridge waveguide switch, a short circuit back plate and a radio frequency connector. The feeding is carried out by combining coaxial waveguide transformation with four-ridge waveguide, and the ridge sheet is designed by adopting the ridge curve in an index form, so that the characteristics of good standing wave, gain and radiation pattern are realized, the size is small, the index is excellent, and the method can be widely applied to the related fields of electronic countermeasure, material testing, 5G communication and the like.

Description

6-40 GHz four-ridge horn antenna

Technical Field

The invention belongs to the technical field of communication, and particularly relates to a 6-40 GHz four-ridge horn antenna.

Background

At present, the rapid development of technologies such as 5G communication, electronic countermeasure, electronic reconnaissance, material testing, etc. has caused a trend that the required bandwidth of an antenna is widened, and the antenna is required to be capable of transmitting and receiving electric wave signals in a wider frequency range in the above fields.

The standard gain horn antenna can be fully applied and developed in the field due to high gain and stable directivity, and can be used as an independent antenna or a feed source under general conditions. However, the working frequency band of the conventional horn antenna is affected by the size of the waveguide, and in order to enable the horn antenna to work in a wide frequency band, the conventional horn antenna needs to be improved, and a ridge-adding manner is generally adopted.

Disclosure of Invention

The invention provides a 6-40 GHz four-ridge horn antenna, which feeds power by combining coaxial waveguide transformation with four-ridge waveguides, and designs ridge pieces by adopting an exponential ridge curve, thereby realizing good standing wave, gain and radiation pattern characteristics.

The technical scheme adopted by the invention for solving the technical problems is as follows:

a6-40 GHz four-ridge horn antenna comprises a rectangular horn, a coaxial four-ridge waveguide switch, a short circuit backboard and a radio frequency connector; the short circuit back plate is connected with the small-caliber part of the rectangular horn and forms a short circuit back cavity with the rectangular horn;

the coaxial four-ridge waveguide conversion device comprises a rectangular waveguide, a ridge sheet I, a ridge sheet II, a ridge sheet III and a ridge sheet IV, wherein the ridge sheet I, the ridge sheet II, the ridge sheet III and the ridge sheet IV are respectively fixed on four inner surfaces of the rectangular horn, the rectangular waveguide is positioned at a small caliber of the rectangular horn and is sleeved outside the ridge sheet I, the ridge sheet II, the ridge sheet III and the ridge sheet IV;

and radio frequency connectors are arranged outside the first ridge piece and the second ridge piece, through holes are formed in corresponding positions, and inner conductors of the radio frequency connectors penetrate through the through holes of the first ridge piece and the second ridge piece and are connected into the opposite fourth ridge piece and the opposite third ridge piece.

Further, the caliber of the rectangular horn is 48mm multiplied by 32mm.

Furthermore, the rectangular horn is divided into a straight section and a horn section, the vertical section of the horn section is rectangular, and the four horn wall surfaces are metal surfaces.

Furthermore, the outer surfaces of the four horn walls are provided with a plurality of square grooves to form a grid shape, and a part of the wall surface is cut off to reduce the weight of the antenna without influencing the performance of the antenna.

Furthermore, the thickness of the ridge piece I, the ridge piece II, the ridge piece III and the ridge piece IV is 1.5-2 mm.

Furthermore, the through holes formed in the first ridge sheet and the second ridge sheet are stepped through holes, and the inner conductor of the radio frequency connector and the stepped through holes form stepped coaxial impedance transformation.

Furthermore, the first ridge piece, the second ridge piece, the third ridge piece and the fourth ridge piece have the same ridge curve, and the ridge curve sequentially comprises a straight line segment and an index gradual change segment along the expansion direction of the caliber of the rectangular horn.

Further, the ridge curve equation of the exponential transition section is as follows:

y＝αe ^βL +kL；

wherein, L is the length of the rectangular horn, the alpha value is between 0.45 and 0.6, the beta value is between 0.002 and 0.003, and the k value is between 0.015 and 0.03.

Furthermore, the bottom ends of the ridge piece I, the ridge piece II, the ridge piece III and the ridge piece IV are all designed with steps, and a better standing-wave ratio is obtained by adjusting the height of the steps; wherein, the control range of step height does: 0.3-0.7 mm.

Furthermore, a cavity is arranged in the short circuit back plate, and a good low-frequency standing-wave ratio is obtained by adjusting the depth of the cavity; wherein, the control range of cavity degree of depth does: 0.8-1.4 mm.

Compared with the prior art, the invention has the beneficial effects that:

1. the four-ridge horn antenna composed of the rectangular horn, the coaxial four-ridge waveguide conversion, the short circuit back plate and the radio frequency connector can obtain good impedance matching in an ultra-wide frequency band and good isolation.

2. Under the condition that the shape and the size of the rectangular horn are fixed, the ridge line equation of the ridge sheet is adjusted, so that the input impedance of the antenna is changed slightly under the condition that the antenna can transmit and receive ultra-wideband radio waves, and the ultra-wideband antenna can transmit and receive the radio waves in a wide frequency range.

3. The size is small: the antenna size is only 70mm x 48mm x 32mm (length x width x height); the weight is light: the outer surfaces of the four horn walls are provided with a plurality of square grooves to form a grid shape, and a part of wall surfaces are cut off to reduce the weight of the antenna without influencing the performance of the antenna.

4. The index is excellent: the standing-wave ratio of the antenna is typically less than 2 at 6-40 GHz.

5. The application is wide: the method is widely applied to the related fields of electronic countermeasure, material testing, 5G communication and the like.

Drawings

FIG. 1 is a schematic view of the overall structure of the present invention;

FIG. 2 is a cross-sectional view of an internal antenna;

in the figure, 1, a rectangular loudspeaker, 2a, first ridge sheets, 2b, second ridge sheets, 2c, third ridge sheets, 2d, fourth ridge sheets, 3, a short-circuit back plate, 4 and a radio frequency connector.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In an embodiment, referring to fig. 1-2, a 6-40 GHz four-ridge horn antenna includes a rectangular horn 1, a coaxial four-ridge waveguide switch, a short-circuit back plate 3, and a radio frequency connector 4; the short circuit back plate 3 is connected with the small-caliber part of the rectangular horn 1 and forms a short circuit back cavity with the rectangular horn 1. The coaxial four-ridge waveguide conversion device comprises a rectangular waveguide, a ridge piece I2 a, a ridge piece II 2b, a ridge piece III 2c and a ridge piece IV 2d, wherein the ridge piece I2 a, the ridge piece II 2b, the ridge piece III 2c and the ridge piece IV 2d are respectively fixed on the inner surface of the rectangular horn 1, the rectangular waveguide is located at the small caliber of the rectangular horn 1 and is sleeved outside the ridge piece I2 a, the ridge piece II 2b, the ridge piece III 2c and the ridge piece IV 2 d. The outer parts of the first ridge piece 2a and the second ridge piece 2b are respectively provided with a radio frequency connector 4, through holes are formed in corresponding positions, and an inner conductor of the radio frequency connector 4 penetrates through the through holes of the first ridge piece 2a and the second ridge piece 2b and is connected into the opposite ridge piece four 2d and the ridge piece three 2 c.

In the structure, the caliber of the rectangular horn 1 is 48mm multiplied by 32mm. Rectangular horn 1 divide into straight section and loudspeaker section, the vertical section of loudspeaker section is the rectangle, and four loudspeaker walls are the metal covering.

Preferably, the outer surfaces of the four horn walls are provided with a plurality of square grooves to form a grid shape, and a part of the wall surface of the outer surface is cut off, so that the weight of the antenna is reduced, and the performance of the antenna is not influenced. And the adjacent horn walls are fixed by rivets, so that the internal antenna is convenient to install.

The ridge thickness, the ridge distance and the transition matching effect of the coaxial probe need to be properly considered, the standing-wave ratio is reduced in the working bandwidth, and the overall performance of the antenna is comprehensively improved. In this embodiment, the thickness of the first ridge piece, the second ridge piece, the third ridge piece and the fourth ridge piece is 1.5-2 mm.

It should be noted that the through holes formed in the first ridge piece 2a and the second ridge piece 2b are stepped through holes, and the inner conductor of the radio frequency connector 4 and the stepped through holes form stepped coaxial impedance transformation. Four-ridge waveguide feed is selected in the design, and the bottom end of the waveguide ridge is designed into a step shape to be beneficial to impedance matching. The excitation of the TE20 mode can be effectively suppressed by adopting a probe feeding mode. The feed part of the horn antenna is a waveguide with the same inner diameter, and because a gap is needed at the connection part of the ridge waveguide and the matching block, the feed part is satisfied by adopting a method of forming a conical groove on the matching block. Meanwhile, the ridge waveguide section (namely the bottoms of the ridge sheet I, the ridge sheet II, the ridge sheet III and the ridge sheet IV) is provided with a step design, the ridge waveguide with the step has good influence on the standing-wave ratio of the antenna, and the excellent standing-wave ratio is obtained by adjusting the height of the step (the height adjusting range is 0.3-0.7 mm).

The design of the horn section is considered from the perspective of gradual impedance changes in the primary mode TE 10. The coaxial input end is matched to the ridge waveguide and the horn open end is matched to the wave impedance of free space. Because the wave impedance is higher when the ridge distance in the ridge waveguide is larger, the ridge distance in the horn section is gradually increased along with the opening of the horn, and the top end of the ridge forms a smooth ridge curve. In order to allow a smooth transition from the coaxial feed point impedance of 50 Ω to the flare free space impedance of 377 Ω, the ridge curve of the flare is also generally exponential. The low-frequency bandwidth can be widened by adding a linear term in the following curve formula, and the axial length of the horn section is shortened;

y＝αe ^βL +kL

wherein: l is the length of the horn, the alpha value is between 0.45 and 0.6, the beta value is between 0.002 and 0.003, and the k value is between 0.015 and 0.03. In this embodiment, L is 50mm.

In order to obtain a wide bandwidth, the length L of the horn should be greater than half the wavelength λ max of the lowest operating frequency to ensure that higher order modes are not excited during the impedance conversion process. Near the flare face, the cross section of the horn is approximately regarded as that of a normal waveguide due to the narrowing of the ridge curve, and the condition for TE10 mode propagation is that the side length S of the flare face is greater than λ max/2.

As a further preferable embodiment of the present invention: a cavity is arranged in the short circuit back plate 3, and a good low-frequency standing-wave ratio is obtained by adjusting the depth of the cavity; wherein, the adjusting range of the cavity depth is as follows: 0.8-1.4 mm.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims

1. A6-40 GHz four-ridge horn antenna is characterized by comprising a rectangular horn (1), a coaxial four-ridge waveguide switch, a short circuit backboard (3) and a radio frequency connector (4); the short circuit back plate (3) is connected with the small-caliber part of the rectangular horn (1) to form a short circuit back cavity with the rectangular horn (1);

the coaxial four-ridge waveguide conversion device comprises a rectangular waveguide, a ridge piece I (2 a), a ridge piece II (2 b), a ridge piece III (2 c) and a ridge piece IV (2 d), wherein the ridge piece I (2 a), the ridge piece II (2 b), the ridge piece III (2 c) and the ridge piece IV (2 d) are respectively fixed on the inner surface of the rectangular loudspeaker (1), the rectangular waveguide is located at the small caliber of the rectangular loudspeaker (1) and sleeved outside the ridge piece I (2 a), the ridge piece II (2 b), the ridge piece III (2 c) and the ridge piece IV (2 d);

and radio frequency connectors (4) are arranged outside the first ridge piece (2 a) and the second ridge piece (2 b), through holes are formed in corresponding positions, and inner conductors of the radio frequency connectors (4) penetrate through the through holes of the first ridge piece (2 a) and the second ridge piece (2 b) and are connected into the opposite ridge piece four (2 d) and the ridge piece three (2 c).

2. The 6-40 GHz four-ridge horn antenna according to claim 1, wherein the aperture of the rectangular horn (1) is 48mm x 32mm.

3. The 6-40 GHz four-ridge horn antenna according to claim 2, wherein the rectangular horn (1) is divided into a straight section and a horn section, the vertical section of the horn section is rectangular, and four horn walls are metal surfaces.

4. The 6-40 GHz four-ridge horn antenna of claim 3, wherein the outer surface of the four horn walls is provided with a plurality of square grooves to form a grid shape, and a part of the wall surface is cut off to reduce the weight of the antenna without affecting the performance of the antenna.

5. The 6-40 GHz four-ridge horn antenna according to claim 1, wherein the thickness of the ridge sheet I (2 a), the ridge sheet II (2 b), the ridge sheet III (2 c) and the ridge sheet IV (2 d) is 1.5-2 mm.

6. The 6-40 GHz four-ridge horn antenna is characterized in that through holes formed in the first ridge sheet (2 a) and the second ridge sheet (2 b) are step-shaped through holes, and the inner conductor of the radio frequency connector (4) and the step-shaped through holes form step-shaped coaxial impedance transformation.

7. The 6-40 GHz four-ridge horn antenna according to claim 6, wherein the ridge sheet I (2 a), the ridge sheet II (2 b), the ridge sheet III (2 c) and the ridge sheet IV (2 d) have the same ridge curve, and the ridge curve sequentially comprises a straight line segment and an exponential gradual change segment along the aperture expansion direction of the rectangular horn (1).

8. The 6-40 GHz four-ridge horn antenna of claim 7, wherein the ridge curve equation of the exponential transition section is as follows:

y＝αe ^βL +kL；

wherein, L is the length of the rectangular loudspeaker (1), the alpha value is between 0.45 and 0.6, the beta value is between 0.002 and 0.003, and the k value is between 0.015 and 0.03.

9. The 6-40 GHz four-ridge horn antenna is characterized in that the bottom ends of the ridge sheet I (2 a), the ridge sheet II (2 b), the ridge sheet III (2 c) and the ridge sheet IV (2 d) are all designed to be steps, and a better standing-wave ratio is obtained by adjusting the heights of the steps; wherein, the control range of step height does: 0.3-0.7 mm.

10. The 6-40 GHz four-ridge horn antenna according to claim 1, characterized in that a cavity is arranged in the short circuit back plate (3), and a good low-frequency standing-wave ratio is obtained by adjusting the depth of the cavity; wherein, the adjusting range of the cavity depth is as follows: 0.8-1.4 mm.