Terahertz clamping type antenna with adjustable focal length

Abstract

The utility model provides a terahertz clamping type antenna with an adjustable focal length, which comprises a main reflector, a feed source and an auxiliary reflector, the feed source and the auxiliary reflector are connected onto the main reflector, an auxiliary reflecting surface of the auxiliary reflector is arranged opposite to a main reflecting surface of the main reflector, and the auxiliary reflecting surface directly faces the feed source; the main reflector is provided with a supporting assembly used for supporting the auxiliary reflector, and the auxiliary reflector is in threaded connection with the supporting assembly so that the focal lengths of the main reflector and the auxiliary reflector can be adjusted. The auxiliary reflector of the antenna is connected with the threads of the supporting assembly through the threads arranged at the rear end, and the axial distance of the main reflector is adjustable through the component, so that the effect of changing the focal length of the card type antenna is achieved, and the focuses of the main reflector and the auxiliary reflector coincide as much as possible to improve the antenna gain; the adverse effect of the initial processing error on the overall performance of the antenna is effectively avoided; the adjusting structure is simple, and the adjusting mode is convenient; the terahertz clamping type antenna with the adjustable focal length is more convenient to operate and high in radiation efficiency, and can be matched with a terahertz communication system to realize longer-distance wireless communication.

Description

TECHNICAL FIELD

[0001] The utility model relates to communication technical field especially relates to an antenna. BACKGROUND

[0002] Terahertz wireless communication is regarded as a key technology of 6G communication, but due to the high terahertz frequency (0.1-10THz), it is easy to be absorbed by oxygen or water molecules when transmitting in the atmosphere, and the attenuation is serious, so the performance of the terahertz antenna plays an important role in the terahertz communication system. Cassegrain antenna is widely used in wireless communication system with high gain demand due to its compact structure, low noise and high efficiency. However, the standard Cassegrain antenna needs the focus of the main reflection paraboloid and the focus of the secondary reflection hyperboloid to completely coincide, so that the spherical wave emitted from the feed source can be reflected by the secondary reflection surface and the main reflection surface to become a plane wave, thereby improving the aperture utilization coefficient and improving the antenna gain. The focus coincidence of the main and secondary reflection surfaces is ensured by the positioning of the secondary reflection surface support rod, which requires high machining precision of the main and secondary reflection surfaces and the secondary reflection surface support rod.

[0003] At present, the existing Cassegrain antenna has the following limitations in structure and performance: 1. Poor consistency and low yield. Due to the structural problem of Cassegrain antenna, high-precision machining precision in microns is required to achieve ideal high-gain indicators, resulting in poor consistency and low yield of Cassegrain antenna; 2. Low radiation efficiency. Due to the non-coincidence of the focus of the secondary reflection surface and the main reflection surface, the electromagnetic wave emitted by the feed source is not reflected as an ideal plane wave, resulting in low radiation efficiency; 3. The focal length of the secondary reflection surface is not adjustable. The inaccurate positioning of the focal length of the secondary reflection surface causes the antenna gain to be too low.

[0004] The Chinese utility model with publication date of 2021.10.26 and publication number of CN 214505783 U discloses a Cassegrain antenna, which comprises a main reflector, a mounting hole is arranged at the center of the main reflector, a radiation feed source is fixed in the mounting hole, a tapered cavity is formed in the radiation feed source, a secondary reflector is arranged at a position opposite to the tapered cavity, the secondary reflector is connected with one end of a support rod through an adjuster, the other end of the support rod is fixedly connected with the main reflector, a waveguide section is fixed outside the radiation feed source, a through hole penetrating through the body of the waveguide section is formed in the waveguide section, one end of the through hole is arranged opposite to one end of the tapered cavity and is in communication with each other. By adjusting the adjuster, the position of the secondary reflector can be adjusted along the axial direction, thereby reducing the influence of machining and assembly errors on the indicators, and making the machining and assembly simpler. However, the focal length adjusting structure of the patent is complex, and the adjusting process is cumbersome. UTILITY MODEL CONTENTS

[0005] The utility model proposes a kind of focal length adjustable terahertz card type antenna for solving the focal length adjusting structure complex of prior art terahertz card type antenna, and the problem of tedious adjusting process.

[0006] In order to achieve the above object, the technical scheme of the utility model is as follows:

[0007] A kind of focal length adjustable terahertz card type antenna, including main reflector, feed source and sub-reflector connected on main reflector, the sub-reflection surface of sub-reflector is oppositely arranged with the main reflection surface of main reflector, and sub-reflection surface is directly opposite feed source;Main reflector is equipped with support assembly for supporting sub-reflector, and sub-reflector is threadedly connected with support assembly to make the focal length of main reflector and sub-reflector adjustable.The utility model antenna's sub-reflector is threadedly connected with the support assembly by rear end setting thread, not only makes the axial distance of main reflector adjustable, to change the effect of card type antenna focal length, make main reflection surface and sub-reflection surface focal point coincide as far as possible to improve antenna gain, effectively avoid the adverse effects of initial machining error on the overall performance of antenna;And adjusting structure is simple, and adjusting mode is convenient;The utility model focal length adjustable terahertz card type antenna as operation is more convenient, and antenna with high radiation efficiency can be matched with terahertz communication system to realize more long-distance wireless communication.

[0008] Further, in order to facilitate the threaded connection of the sub-reflector and the support assembly, the support assembly is provided with an internal thread hole, and the rear end of the sub-reflector is provided with an external thread column threadedly matched with the internal thread hole.

[0009] Further, in order to facilitate the fixation of the sub-reflector after distance adjustment, the rear end of the external thread column is threadedly connected with a fastening nut.

[0010] Further, in order to support the sub-reflector at a position directly opposite the center feed source of the main reflector, the support assembly includes a sub-reflector fixing seat and at least two sub-reflector support rods, one end of the sub-reflector support rod is connected with the main reflector, and the other end is connected with the sub-reflector fixing seat; The internal thread hole is arranged on the sub-reflector fixing seat.

[0011] Further, in order to better fix the sub-reflector support rod on the main reflector, the sub-reflector support rod is connected with the main reflector through a sub-reflector support rod fixing seat.

[0012] Further, the main reflection surface is a parabolic surface.

[0013] Further, the sub-reflection surface is a hyperboloid.

[0014] Further, in order to facilitate the processing of the feed, the feed comprises a spliced feed upper end cover and a feed lower end cover, and each of the feed upper end cover and the feed lower end cover is provided with a half feed hole to form the feed hole after the splicing of the feed upper end cover and the feed lower end cover.

[0015] Further, in order to facilitate the splicing and fixing of the two feed end covers, the feed upper end cover and the feed lower end cover are connected with the main reflector through fixing screws respectively.

[0016] Further, in order to facilitate the setting of the antenna end cover, the rear end of the feed is sleeved with an antenna end cover, and the antenna end cover is connected to the back of the main reflector through a fixing screw.

[0017] The beneficial effects of the present application are as follows:

[0018] 1. The terahertz lens antenna of the present application can be used as an antenna with higher radiation efficiency and more convenient operation to realize wireless communication at a longer distance in combination with a terahertz communication system.

[0019] 2. The threaded connection between the rear end of the sub-reflector of the antenna and the support assembly makes the axial distance of the main reflector adjustable, thereby changing the focal length of the lenticular antenna and making the focal points of the main and sub-reflection surfaces coincide as much as possible to improve the antenna gain and effectively avoid the adverse effects of the initial processing error on the overall performance of the antenna.

[0020] 3. The tightening of the nut after the adjustment of the sub-reflector makes the sub-reflector more stable and avoids loosening.

[0021] 4. The surfaces of the main reflector and the sub-reflector and the feed of the present application are all silver-plated to effectively reduce the high-frequency skin effect and thereby reduce the metal loss, and the material and the plating layer can meet the working temperature requirement of-20℃ to 60℃.

[0022] 5. The main and sub-reflection surfaces of the lenticular antenna of the present application are both made of aluminum, and the small part of the feed is made of copper, which can greatly reduce the weight of the antenna itself while ensuring the performance of the antenna and has strong mechanical stability.

[0023] 6. The main and sub-reflection surfaces of the present application are both polished to improve the reflection efficiency, and these process treatments can effectively reduce the return loss of the antenna and improve the radiation efficiency.

[0024] 7. The support rod of the sub-reflector in the antenna of the present application adopts a strip structure to minimize the shielding of the electromagnetic wave by the sub-reflection surface antenna. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiment or prior art description. Obviously, the drawings described below are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0026] Figure 1 It is a sectional view structural schematic diagram of the present application.

[0027] Figure 2 It is a rear view structural schematic diagram of the present application.

[0028] Figure 3 It is a three-dimensional structural schematic diagram of the present application.

[0029] Figure 4 It is a sectional view structural schematic diagram of the present application. Figure 3

[0030] Figure 5 It is a working principle diagram of the present application.

[0031] Reference signs in the drawings:

[0032] 1, sub-reflector support rod fixing seat, 2, flat washer, 3, spring washer, 4, antenna end cover, 5, upper end cover of feed source, 6, fixing screw, 7, lower end cover of feed source, 8, main reflector, 81, main reflecting surface, 9, sub-reflector, 91, sub-reflector surface, 10, sub-reflector support rod, 11, sub-reflector fixing seat, 12, fastening nut. DETAILED DESCRIPTION

[0033] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0034] As Figure 1 and Figure 3 ​As shown in the utility model embodiment 1 is shown, a kind of terahertz Cassegrain antenna of focal length adjustable, including main reflector 8, feed source and sub-reflector 9, feed source and sub-reflector 9 are connected with main reflector 8. Wherein, feed source is arranged at the center position of main reflector 8, and feed source is coaxially arranged with main reflector 8. Sub-reflector 9 is oppositely arranged with main reflector 8, to make the sub-reflector 9 sub-reflector surface 91 with main reflector 8 main reflector surface 81 opposite. And make sub-reflector surface 91 directly face the feed source hole of feed source. Main reflector 8 is equipped with support assembly for supporting sub-reflector 9, sub-reflector 9 is threadedly connected with support assembly, by rotating sub-reflector 9 to make sub-reflector 9 produce axial movement under the action of screw thread, to make the focal length of sub-reflector 9 and main reflector 8 adjustable.

[0035] Specifically, the support assembly includes a sub-reflector fixing seat 11 and at least two sub-reflector support rods 10. One end of the sub-reflector support rod 10 is connected with the main reflector 8, and the other end extends inward towards the axis of the main reflector 8 for connecting the sub-reflector fixing seat 11. The sub-reflector fixing seat 11 is arranged on the axis of the main reflector 8, and the sub-reflector fixing seat 11 is a certain distance from the feed source at the center of the main reflector 8, so that the sub-reflector surface 91 of the sub-reflector 9 arranged on the sub-reflector fixing seat 11 directly faces the feed source. The inward end of the sub-reflector support rod 10 is connected with the sub-reflector fixing seat 11, and the sub-reflector support rod 10 supports the sub-reflector fixing seat 11. The sub-reflector support rods 10 are evenly distributed around the axis of the main reflector 8 at equal angles.

[0036] Further, the sub-reflector fixing seat 11 is provided with an internal threaded hole, and the axis of the internal threaded hole coincides with the axis of the main reflector 8. The rear end of the sub-reflector 9 is provided with an external threaded column that penetrates the internal threaded hole and threadedly cooperates with the internal threaded hole. The sub-reflector 9 is threadedly connected by rotating the external threaded column into the internal threaded hole of the sub-reflector fixing seat 11, which facilitates the adjustment of the position of the sub-reflector 9 by rotating the sub-reflector 9 to move along the axis of the main reflector 8, thereby adjusting the focal length of the sub-reflector 9 and the main reflector 8.

[0037] Embodiment 2, which is different from embodiment 1, as shown in Figure 4 The rear end of the external threaded column is threadedly connected with a fastening nut 12. After the sub-reflector 9 is rotated into the internal threaded hole of the sub-reflector fixing seat 11, the fastening nut 12 is rotated from the rear end of the external threaded column until it is tightened against the sub-reflector fixing seat 11 to fasten the sub-reflector 9. By loosening the fastening nut 12, the position of the sub-reflector 9 can be adjusted by rotating the sub-reflector 9, thereby adjusting the focal length. After adjusting to the appropriate position, the fastening nut 12 is tightened against the sub-reflector fixing seat 11 by tightening the fastening nut 12, thereby fixing the adjusted sub-reflector 9.

[0038] Example 3, which differs from example 2 in that, as shown in Figure 1 and Figure 3 The sub-reflector support rod 10 is connected with the main reflector 8 through the sub-reflector support rod fixing seat 1, that is, the outer end of the sub-reflector support rod 10 is connected with the sub-reflector support rod fixing seat 1, and the sub-reflector support rod fixing seat 1 is arranged on the main reflector 8 to serve as a connection between the sub-reflector support rod 10 and the main reflector 8. In this embodiment, the end of the sub-reflector support rod 10 is connected with the sub-reflector support rod fixing seat 1 through a bolt.

[0039] Example 4, which differs from example 1 in that, as shown in Figure 1 and Figure 4 The feed source comprises a feed source upper end cover 5 and a feed source lower end cover 7 which are spliced together. As shown in Figure 3 The main body part of the feed source upper end cover 5 and the feed source lower end cover 7 is a half-cylinder respectively, so that the main body part of the feed source upper end cover 5 and the feed source lower end cover 7 becomes a complete cylindrical feed source after splicing. A half feed source hole extending along the feed source axis is arranged on the splicing surface of the feed source upper end cover 5 and the feed source lower end cover 7, and the two half feed source holes form a complete feed source hole after the feed source upper end cover 5 and the feed source lower end cover 7 are spliced together. The feed source is arranged in a spliced structure, so that the processing and manufacturing of the feed source are simpler and the performance is more reliable.

[0040] Further, as shown in Figure 1 and Figure 4 The feed source upper end cover 5 and the feed source lower end cover 7 are connected with the main reflector 8 through fixing screws 6. The rear end of the feed source upper end cover 5 and the feed source lower end cover 7 is respectively provided with a boss extending radially outward, which cooperates with the back surface of the main reflector 8. The fixing screws 6 are screwed into the main reflector 8 through the bosses to connect and fix the feed source upper end cover 5 and the feed source lower end cover 7 with the main reflector 8.

[0041] Example 5, which differs from example 4 in that, as shown in Figure 2 The rear end of the feed source is sleeved with an antenna end cover 4, and the antenna end cover 4 is connected with the main reflector 8 through the fixing screws 6. The fixing screws 6 are screwed into the main reflector 8 through the antenna end cover 4 to connect and fix the antenna end cover 4 with the main reflector 8.

[0042] Example 6, which differs from example 5 in that, as shown in Figure 1 A circle of screws for mounting and fixing the terahertz horn antenna are arranged on the antenna end cover 4, and a flat washer 2 and a spring washer 3 are sleeved on the screws.

[0043] Example 7: The working process of this utility model is as follows: The main reflector 8 and the sub-reflector 9 are both made of aluminum, and a small part of the feed source is made of copper. Furthermore, the surfaces of the main reflector 8, the sub-reflector 9, and the feed source, as well as the inner wall of the feed source aperture, are all silver-plated, which can effectively reduce metal loss caused by the high-frequency skin effect. The materials and plating of the main reflector 8, the sub-reflector 9, and the feed source can all meet the operating temperature requirements of -20℃ to 60℃.

[0044] Example 8: The working process of this utility model is as follows:

[0045] The antenna signal is first emitted from the feed F2 at the bottom center of the main reflector towards the sub-reflector, then reflected back to the main reflector by the sub-reflector, and finally reflected a second time by the main reflector into free space. Its basic working principle is as follows: Figure 5 As shown, in this embodiment, the primary reflector 81 of the card antenna is a paraboloid of revolution, and the secondary reflector 91 is a hyperboloid of revolution. F (F1) is both the focus of the primary paraboloid and one of the focuses of the secondary hyperboloid, while F2 is the other focus of the secondary reflector. During the first reflection, the backward extensions of the spherical waves emitted from focus F2 on one side of the secondary hyperboloid, after being reflected by the hyperboloid, all intersect at the other focus F1. These electromagnetic waves after the first reflection can be considered as spherical waves emitted from an equivalent point source F in ray optics. Therefore, in the second reflection, all the waves emitted from the primary paraboloid are transformed into uniform plane waves parallel to the antenna's focal axis.

[0046] This invention can be used for 220GHz terahertz signals, but is not limited to this frequency signal. It is also applicable to common terahertz frequencies such as 140GHz and 340GHz, as well as other millimeter wave signals.

[0047] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any modifications to the technical solutions described in the foregoing embodiments, or equivalent substitutions of some or all of the technical features therein, within the spirit and principles of the present utility model, shall not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present utility model, and shall all be included within the protection scope of the present utility model.

Claims

1. A terahertz cassette antenna with adjustable focal length, characterized in that, It includes a main reflector (8), a feed source connected to the main reflector (8), and a sub-reflector (9). The sub-reflecting surface (91) of the sub-reflector (9) is set opposite to the main reflecting surface (81) of the main reflector (8), and the sub-reflecting surface (91) faces the feed source. The main reflector (8) is provided with a support assembly for supporting the sub-reflector (9). The sub-reflector (9) is threadedly connected to the support assembly so that the focal length of the main reflector (8) and the sub-reflector (9) is adjustable.

2. The adjustable focal length terahertz cassette antenna according to claim 1, characterized in that, The support component is provided with an internal threaded through hole, and the rear end of the sub-reflector (9) is provided with an external threaded post that is threadedly engaged with the internal threaded through hole.

3. The adjustable focal length terahertz cassette antenna according to claim 2, characterized in that, The rear end of the external threaded column is threaded with a fastening nut (12).

4. The adjustable focal length terahertz cassette antenna according to claim 2 or 3, characterized in that, The support assembly includes a sub-reflector mounting base (11) and at least two sub-reflector support rods (10). One end of the sub-reflector support rod (10) is connected to the main reflector (8), and the other end is connected to the sub-reflector mounting base (11). The internal threaded through hole is provided on the sub-reflector mounting base (11).

5. The adjustable focal length terahertz cassette antenna according to claim 4, characterized in that, The sub-reflector support rod (10) is connected to the main reflector (8) through the sub-reflector support rod fixing seat (1).

6. The adjustable focal length terahertz cassette antenna according to any one of claims 1 to 3 and 5, characterized in that, The main reflecting surface (81) is a parabolic surface.

7. The adjustable focal length terahertz cassette antenna according to claim 6, characterized in that, The sub-reflective surface (91) is a hyperboloid.

8. The adjustable focal length terahertz cassette antenna according to any one of claims 1 to 3, 5 and 7, characterized in that, The feed source includes a feed source upper end cover (5) and a feed source lower end cover (7) that are spliced ​​together. Each of the feed source upper end cover (5) and the feed source lower end cover (7) is provided with half a feed source hole so that the feed source hole is formed after the feed source upper end cover (5) and the feed source lower end cover (7) are spliced ​​together.

9. The adjustable focal length terahertz cassette antenna according to claim 8, characterized in that, The upper end cover (5) and the lower end cover (7) of the feed source are respectively connected to the main reflector (8) by fixing screws (6).

10. The adjustable focal length terahertz cassette antenna according to any one of claims 1 to 3, 5, 7 and 9, characterized in that, The rear end of the feed is fitted with an antenna end cap (4), which is connected to the back of the main reflector (8) by fixing screws (6).

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