TWI732453B - A structure of dish antenna - Google Patents

Abstract

A reflector antenna structure consisting of a main reflector, a secondary reflector and a feed antenna, wherein the main reflector is a paraboloid, and the secondary reflector is a hyperboloid and is connected to a conical surface near its vertex. The focal point of the hyperboloid is set near the focal point of the parabola, and the feed source antenna has a radiating aperture disposed near another focal point of the conical surface.

Description

Dish antenna structure

The present invention relates to a dish antenna structure, in particular to a millimeter wave high gain dish antenna structure with the advantages of low loss and light weight.

Due to the rapid development of mobile communications in recent years, the importance of multi-beam communications technology has increased day by day, and in response to the advent of the fifth generation of mobile communications, the frequency band used by antennas has a tendency to use high frequency bands, and its application has been towards millimeter wave frequency bands. For the millimeter wave frequency band used in satellite communications, the microwave wavelength and antenna structure will become smaller, and the loss will be great when propagating in the air, and because of the multi-application multi-channel concept, it is hoped that the multi-beam can be achieved. Utilization, and the current implementation of high-gain antennas is traditionally implemented with phased array antennas, especially focusing on the use of PCB or LTCC processes to implement related hardware, which has become the mainstream of mobile communication technology development in the past. However, if the frequency band required for planning is a millimeter wave frequency band, it will face quite a lot of challenges in technology and hardware implementation, especially the realization of related hardware for high-gain antennas (or RF-related technologies) for 5G. In the realization of, there will be a lot of energy loss, which will cause noise interference.

The above-mentioned situation is more difficult to control the characteristics of active components, including amplitude changes and RF phase changes which are quite unstable, which will vary with the temperature of the environment, the size of the noise, and even different manufacturing batches. In particular, the realization of the array antenna needs to be matched with the feeding radio frequency circuit, and its composition will use the same With many active components, this type of circuit will lose considerable energy in millimeter waves. In order to maintain the required antenna gain, the number of antenna elements must be increased. For example, when the antenna circuit loss is 3dB, the number of antenna elements must be doubled to compensate This energy loss, however, even if the number of antennas doubles, the complexity of the RF feed circuit will further increase, and synchronization will increase the energy loss, so the actual number of antennas will be considerable. In addition, the formation of the beam of the array antenna requires the phase change of the phase shifter to achieve the desired beam. In the millimeter wave frequency band, active components and passive components will produce unstable phase differences, so it is necessary to form the required beam It is quite difficult.

Therefore, in order to overcome the above-mentioned problems, the dish antenna is used in this case. In addition to using the dual-reflector Cassegrain architecture to achieve high gain to meet specifications, the dielectric part is also made of Rexolite material to reduce path loss. This case should be the best The best solution.

The present invention provides a dish antenna structure, which includes: a dish-shaped main reflector with a parabolic surface; a primary reflector, which essentially has a hyperboloid and connects a conical surface near the vertex, and the hyperboloid focus is set Near the focal point of the parabola; and a feed source antenna with a radiating hole arranged near the other focal point of the conical surface.

More specifically, the feed source antenna has an inner wall 102 and an outer wall 101, the inner wall is coupled to the radiating hole, the outer wall is connected to the radiating hole by a feeding gradient surface 101a, and the inner wall The wall constitutes a waveguide to transmit electromagnetic waves to the radiation hole.

More specifically, the feeding gradual change surface is a linear rotating surface.

More specifically, the bottom diameter of the feeding gradual change surface is the diameter of the outer wall, the upper bottom diameter of the feeding gradual change surface is the diameter of the inner wall, and the height of the linear rotation surface is the distance from the radiation hole to the outer wall. distance.

More specifically, the diameter of the outer wall is 6.0725 mm, the diameter of the inner wall is 3.175 mm, and the distance from the radiation hole to the outer wall is 15 mm.

More specifically, the secondary reflector is a solid dielectric adapter, which has a dielectric rotating surface, an incident surface, and an exit surface. The exit surface has a larger diameter than the incident surface, and the incident surface is coupled to The radiation hole and the exit surface are coupled to the primary reflective surface.

More specifically, the secondary reflective surface is printed on the surface of the exit surface.

More specifically, there is a rotating stepped surface near the incident surface to connect the dielectric rotating surface and the radiation hole for impedance matching.

More specifically, the solid dielectric adapter is made of Rexolite plastic.

More specifically, the dielectric coefficient of the solid dielectric adapter is 2.53.

More specifically, the dielectric rotating surface is a linear rotating surface.

A dish antenna structure in this case includes: a primary reflector, which essentially has a hyperboloid and is connected to a conical surface near the vertex, the hyperboloid focal point is set near the parabolic focal point; and a feed-in source antenna having A radiation hole is arranged near the other focal point of the conical surface.

More specifically, the feed source antenna has an inner wall and an outer wall, the inner wall is coupled to the radiating hole, the outer wall and the radiating hole are connected by a feeding gradient surface, and the inner wall constitutes a wave The tube transmits electromagnetic waves to the radiation hole.

More specifically, the feeding gradual change surface is a linear rotating surface.

More specifically, the bottom diameter of the feeding gradual change surface is the diameter of the outer wall, the upper bottom diameter of the feeding gradual change surface is the diameter of the inner wall, and the height of the linear rotating surface is the distance from the radiating hole to the outer wall. .

More specifically, the diameter of the outer wall is 6.0725 mm, the diameter of the inner wall is 3.175 mm, and the distance from the radiation hole to the outer wall is 15 mm.

More specifically, the secondary reflector is a solid dielectric adapter, which has a dielectric rotating surface, an incident surface, and an exit surface. The exit surface has a larger diameter than the incident surface, and the incident surface is coupled to The radiation hole and the exit surface are coupled to the primary reflective surface.

More specifically, the secondary reflective surface is printed on the surface of the exit surface.

More specifically, there is a rotating stepped surface near the incident surface to connect the dielectric rotating surface and the radiation hole for impedance matching.

More specifically, the solid dielectric adapter is made of Rexolite plastic.

More specifically, the dielectric coefficient of the solid dielectric adapter is 2.53.

More specifically, the dielectric rotating surface is a linear rotating surface.

10: Feed into the source antenna

101: Outer Wall

101a: Feed into the gradient surface

102: inner wall

20: secondary reflector

201: exit surface

2011: secondary reflective surface

202: incident surface

203: Dielectric rotating surface

204: Rotating Step Surface

30: Dish-shaped main reflector

[Figure 1A] is an overall schematic diagram of the dish antenna structure of the present invention.

[Figure 1B] is a schematic cross-sectional view of the entire dish antenna structure of the present invention.

[Figure 2A] is a schematic diagram of the dish-shaped main reflector of the dish-shaped antenna structure of the present invention.

[Figure 2B] is a schematic diagram of the cross-sectional structure of the dish-shaped main reflector of the dish-shaped antenna structure of the present invention.

[Figure 3] is a schematic view of the focal point of the dish-shaped main reflector of the dish-shaped antenna structure of the present invention.

[Figure 4A] is the focal point and schematic diagram of the dish-shaped main reflector of the dish-shaped antenna structure of the present invention.

[Figure 4B] is the focal point and schematic diagram of the dish-shaped main reflector of the dish-shaped antenna structure of the present invention.

[Figure 5] is a schematic diagram of the modal configuration of the dish antenna structure of the present invention.

[Figure 6A] is a schematic diagram of the feed-in antenna structure of the dish antenna structure of the present invention.

[Figure 6B] is a schematic diagram of the cross-sectional structure of the feed-in source antenna of the dish antenna structure of the present invention.

[Figure 7A] is a two-dimensional simulated beam radiation pattern diagram of the feed source antenna of the dish antenna structure of the present invention.

[Figure 7B] is a two-dimensional simulated beam radiation pattern diagram of the feed source antenna of the dish antenna structure of the present invention.

[Figure 7C] is a two-dimensional simulated beam radiation pattern diagram of the feed source antenna of the dish antenna structure of the present invention.

[Figure 7D] is a two-dimensional simulated beam radiation pattern diagram of the feed source antenna of the dish antenna structure of the present invention.

[Figure 8A] is a three-dimensional simulated beam radiation pattern diagram of the feed source antenna of the dish antenna structure of the present invention.

[Figure 8B] is a three-dimensional simulated beam radiation pattern diagram of the feed source antenna of the dish antenna structure of the present invention.

[Figure 8C] is a three-dimensional simulated beam radiation pattern diagram of the feed source antenna of the dish antenna structure of the present invention.

[Figure 8D] is a three-dimensional simulated beam radiation pattern diagram of the feed source antenna of the dish antenna structure of the present invention.

[Figure 9] is a schematic diagram of the simulated standing wave ratio of the feed source antenna of the dish antenna structure of the present invention.

[Figure 10A] is a schematic diagram of the optimized design structure of the feed source antenna and the sub-reflector of the dish antenna structure of the present invention.

[Figure 10B] is a schematic cross-sectional structure diagram of the optimized design of the feed source antenna and the sub-reflector of the dish antenna structure of the present invention.

[Figure 11A] is a two-dimensional simulated beam radiation pattern diagram of the feed source antenna and the sub-reflector of the dish antenna structure of the present invention.

[Figure 11B] is a two-dimensional simulated beam radiation pattern diagram of the feed source antenna and the sub-reflector of the dish antenna structure of the present invention.

[Figure 11C] is a two-dimensional simulated beam radiation pattern diagram of the feed source antenna and the sub-reflector of the dish antenna structure of the present invention.

[Figure 11D] The two-dimensional simulated beam of the feed source antenna and the sub-reflector of the dish antenna structure of the present invention Radiation pattern diagram.

[Figure 12A] is a three-dimensional simulated beam radiation pattern diagram of the feed source antenna and the sub-reflector of the dish antenna structure of the present invention.

[Figure 12B] is a three-dimensional simulated beam radiation pattern diagram of the feed source antenna and the sub-reflector of the dish antenna structure of the present invention.

[Figure 12C] is a three-dimensional simulated beam radiation pattern diagram of the feed source antenna and the sub-reflector of the dish antenna structure of the present invention.

[Figure 12D] is a three-dimensional simulated beam radiation pattern diagram of the feed source antenna and the sub-reflector of the dish antenna structure of the present invention.

[Figure 13] is a schematic diagram of the simulated standing wave ratio of the feed source antenna and the sub-reflector of the dish antenna structure of the present invention.

[Figure 14A] is a schematic diagram of the parabola principle of the dish antenna structure of the present invention.

[Figure 14B] is a schematic diagram of the parabola principle of the dish antenna structure of the present invention.

[Figure 15A] is a schematic diagram of the parabolic construction of the dish antenna structure of the present invention.

[Figure 15B] is a schematic diagram of the parabolic construction of the dish antenna structure of the present invention.

[Figure 16A] is the two-dimensional simulated beam radiation pattern of the millimeter wave high gain dish antenna combined with the feed source antenna, the secondary reflector, and the dish primary reflector of the dish antenna structure of the present invention.

[Figure 16B] is the two-dimensional simulated beam radiation pattern of the millimeter wave high gain dish antenna combined with the feed source antenna, the secondary reflector, and the dish primary reflector of the dish antenna structure of the present invention.

[Figure 16C] is the two-dimensional simulated beam radiation pattern of the millimeter wave high gain dish antenna after the feed source antenna, the secondary reflector, and the dish primary reflector of the dish antenna structure of the present invention are combined.

[Figure 16D] Feeding source antenna, secondary reflector, and primary dish reflector of the dish antenna structure of the present invention The two-dimensional simulated beam radiation pattern of the combined millimeter wave high-gain dish antenna.

[Figure 17A] is the three-dimensional simulated beam radiation pattern of the millimeter wave high gain dish antenna with the dish antenna structure of the present invention.

[Figure 17B] is the three-dimensional simulated beam radiation pattern of the millimeter wave high gain dish antenna with the dish antenna structure of the present invention.

[Figure 17C] is the three-dimensional simulated beam radiation pattern of the millimeter wave high gain dish antenna with the dish antenna structure of the present invention.

[Figure 17D] is the three-dimensional simulated beam radiation pattern of the millimeter wave high gain dish antenna with the dish antenna structure of the present invention.

[Figure 18] is a schematic diagram of the simulated standing wave ratio of the millimeter wave high gain dish antenna with the dish antenna structure of the present invention.

[Figure 19] is a schematic diagram of the erection of the beam radiation field pattern test of the dish antenna structure of the present invention.

[Figure 20A] is the implementation of the two-dimensional measurement beam radiation pattern of the millimeter wave high-gain antenna with the dish antenna structure of the present invention.

[Figure 20B] is the implementation of the two-dimensional measurement beam radiation pattern of the millimeter wave high gain antenna with the dish antenna structure of the present invention.

[Figure 20C] is the implementation of the two-dimensional measurement beam radiation pattern of the millimeter wave high gain antenna with the dish antenna structure of the present invention.

[Figure 20D] is the implementation of the two-dimensional measurement beam radiation pattern of the millimeter wave high gain antenna with the dish antenna structure of the present invention.

[Figure 21A] is the implementation of the three-dimensional measurement beam radiation pattern of the millimeter wave high gain antenna with the dish antenna structure of the present invention.

[Figure 21B] is the implementation of the three-dimensional measurement beam radiation pattern of the millimeter wave high gain antenna with the dish antenna structure of the present invention.

[Figure 21C] is the implementation of the three-dimensional measurement beam radiation pattern of the millimeter wave high gain antenna with the dish antenna structure of the present invention.

[Figure 21D] is the implementation of the three-dimensional measurement beam radiation pattern of the millimeter wave high gain antenna with the dish antenna structure of the present invention.

[Figure 22] is a schematic diagram of measuring standing wave ratio of millimeter wave high gain antenna with dish antenna structure of the present invention.

[Figure 23A] is a 45-degree structural diagram of the dish-shaped main reflector of the dish-shaped antenna structure of the present invention.

[Figure 23B] is a schematic diagram of the side structure of the dish-shaped main reflector of the dish-shaped antenna structure of the present invention.

In order to further understand the technology, means and effects adopted by the present invention to achieve the predetermined purpose, please refer to the following detailed description and drawings of the present invention. The purpose, features, or characteristics of the present invention can be obtained from this in-depth and specific understanding, but the accompanying drawings are only provided for reference and explanation, and are not used to limit the present invention.

Please refer to Figs. 1A and 1B. The dish antenna of the present invention includes a feed source antenna 10, a primary reflector 20, and a dish-shaped main reflector 30. As shown in Figs. 2A, 2B and 3, the dish-shaped main reflector The device 30 is a parabolic mask with a focal point F.

As shown in Figures 4A and 4B, the dish antenna in this case is a Cassegrain reflector antenna. The dish-shaped main reflector 30 is a parabolic surface with a focal point F, and the secondary reflector 20 is a hyperboloid with two Focal points F1 and F2, where F2 overlaps with the parabolic focal point F of the dish-shaped main reflector 30, the feed source antenna 10 is located at the hyperboloid focal point F1 of the secondary reflector 20, when electromagnetic waves are incident on the secondary reflector from the feed source antenna 10 On the hyperboloid of 20, the reflection direction is a straight line extending from the other focal point F2 to the reflection point P1. This design is further This step replaces the focal point of the dish-shaped main reflector 30, effectively reducing the problem of excessively long focal length of the dish-shaped main reflector 10.

The design of the feed source antenna 10 in this case is mainly based on the waveguide. Its basic function is to generate a beam radiation field to cover the entire effective surface area of the dish antenna. Its specification is -10B beam width to cover the effective use of the dish main reflection.器30 area.

其中f _c為截止頻率，a為圓柱形波導管半徑，設計圓柱形波導管的饋入源天線10時，必須要設置在E-Band之基本模態，並且在饋入源天線後端設計圓導波管轉矩形導波管之設計，為了配合波導管饋入網路之介面端口，設計圓柱形波導管的饋入源天線10的端口口徑必須與饋入網路的矩形波導管口徑一致，由方程式(1)計算饋入源天線10的口徑為3.175mm，此模態位於TE ₁₁ Mode，也就是位於圓柱形波導管在E-Band之基本模態。 The feed source antenna 10 in this case is selected as a cylindrical waveguide, which has a cylindrical symmetrical structure. When applied to a millimeter wave high-gain antenna, it can reduce unnecessary scattering and diffraction compared with a rectangular waveguide, and the cylindrical symmetrical structure can make the beam The radiation field forms cylindrical symmetry. Cylindrical waveguide modes can be divided into TE (Transverse Electronic) and TM (Transverse Magnetic). The cut-off frequencies are shown in Tables 1A and 1B and Figure 5. The cut-off of the feed source antenna 10 of the cylindrical waveguide is designed. The frequency is:

Where f _c is the cut-off frequency and a is the radius of the cylindrical waveguide. When designing the feeding source antenna 10 of the cylindrical waveguide, it must be set in the basic mode of E-Band, and a circle is designed at the rear end of the feeding source antenna. In the design of stilling wave tube to rectangular wave guide, in order to match the interface port of the waveguide feeding network, the port diameter of the feeding source antenna 10 of the cylindrical waveguide design must be the same as that of the rectangular waveguide feeding the network. The aperture of the feed source antenna 10 is calculated from equation (1) to be 3.175mm, and this mode is located in the TE ₁₁ Mode, which is the basic mode located in the E-Band of the cylindrical waveguide.

As shown in Figures 6A and 6B, the feed source antenna 10 has an outer wall 101 and an inner wall 102. The end of the outer wall 101 has a feeding tapered surface 101a for connecting the outer wall 101 and the inner wall 102, and the feeding tapered surface 101a It has an oblique angle, so that the electromagnetic wave reflected by the secondary reflector 20 can be guided to the main dish-shaped reflector 30 through the electromagnetic waveguide through the oblique angle, so as to reduce the diffraction, scattering, and shielding of the feed source antenna 10 generated by the secondary reflector 20 Benefits, the feeding gradient surface 101a of the feeding source antenna and related size design can be seen in Table 2 and Figure 6B.

In the analog design of the feed source antenna 10, there are two rigorous key points that must be determined. The first is whether the standing wave ratio meets the specifications and is less than 1.5 or less, because it is related to the standing wave ratio of the sub-reflector 20 added later, and the second The point is that the beam radiation pattern must meet the overlap between E-Plane and H-Plane. This is the core key technology of the feed source antenna 10. The specification of the beam radiation pattern in the dish antenna is for both Planes. It meets the requirements of Class 3, and there is also a Cross-Pol Level that focuses on the beam radiation pattern. The feed source antenna 10 must be designed very well, because the addition of a secondary reflector 20 will also determine whether the Cross-Pol Level will be According to the specification requirements, four frequency points of E-Band were selected for observation in the simulation. The four points of 71GHz, 76GHz, 81GHz, and 86GHz represent the highest and lowest frequency points of the frequency band, as shown in Figures 7A to 7D. The two-dimensional simulated beam radiation pattern of the source antenna 10 is shown, and the graphs 8A to 8D are the three-dimensional simulated beam radiation pattern of the feed source antenna 10, and the 9th graph is the simulated standing wave ratio of the feed source antenna 10.

Since the sub-reflector of a typical Cassegrain reflector antenna is usually made of all metal and has a certain weight, in order to achieve a lightweight effect, the feed source antenna 10 is designed to achieve air-tight function. A hyperboloid with a sub-reflector 20 on one end surface of a dielectric material is introduced. As shown in Figures 23A and 23B, the sub-reflector 20 can be made of a dielectric material, which has a dielectric rotating surface (double Curved surface) 203 and an exit surface (conical surface) 201, the dielectric rotating surface (hyperboloid) 203 can be sprayed with metallic paint to achieve a reflection effect, and the exit surface (conical surface) 201 is used to connect the feed source antenna 10 And by fine-tuning the bevel angle, the electromagnetic wave of the feed source antenna 10 can be correctly incident on the dielectric rotating surface (hyperboloid) 203, so one end is connected to the dielectric rotating surface (hyperboloid) 203, and the other end is connected to the feed source antenna 10. , So its diameter is the same as the diameter of the feed source antenna 10. A stepped impedance matcher 50 can be added between the exit surface (cone surface) 201 and the feed source antenna 10 to achieve impedance matching. Please refer to Figure 4A. The dish surface of the reflector 20 can be used to calculate the opening angle and the size by using optical principles.

In the millimeter wave frequency band, the loss is very serious, so the correct dielectric material can reduce the loss in the path. The dielectric material in this case is composed of Rexolite, and its dielectric material loss coefficient in the millimeter wave high frequency band is 0.000666, which is very good. .

After the design of the feed source antenna 10 and the secondary reflector 20 is completed, it must be combined to simulate whether their electrical properties meet the expected requirements, and the shielding benefit must be minimized. The requirement is to combine the feed source antenna 10 and the secondary reflector 20 The beam radiation pattern can be very close to the beam radiation pattern produced by the feed-in source antenna 10 alone. As shown in Figs. 10A and 10B, it is an optimized design for the combined feed-in source antenna 10 and the sub-reflector 20. After the combination, there are two key points that must be determined: (1) The first is that the standing wave ratio after the feed source antenna 10 is added to the secondary reflector 20 is less than 1.5; (2) The second is that the feed source antenna 10 is added to the secondary reflector. The E-Plane and H-Plane of the beam radiation pattern after 20 must have a considerable overlap. This is the key point when the feed source antenna 10 is added to the secondary reflector 20. The field pattern specification in the dish antenna is two Each Plane must meet Class 3 requirements; (3) Another important point is the Cross-Pol Level of the beam radiation field. The design must be very good after the feed source antenna 10 is added to the secondary reflector 20, because the addition of the dish-shaped primary reflector 30 will determine the Cross-Pol Level Will it pass the specification? In the simulation, we selected four frequency points of E-Band for observation, which are 71GHz, 76GHz, 81GHz, 86GHz. As shown in Figures 11A to 11D, it is the feed source antenna 10. The two-dimensional simulated beam radiation pattern on the surface of the secondary reflector 20, and as shown in Figures 12A to 12D, are the three-dimensional simulated beam radiation pattern of the feed source antenna 10 and the secondary reflector 20, and as shown in Figure 13 As shown in the figure, it is the simulated standing wave ratio after the feed source antenna 10 and the sub-reflector 20 are combined.

As shown in Figures 10A, 10B, 23A, and 23B, the sub-reflector 20 is a solid dielectric adapter, which has a dielectric rotating surface 203 (hyperboloid), an incident surface 202, and an exit surface 201. The exit surface 201 has a larger diameter than the entrance surface 202, the entrance surface 202 is coupled to the radiation hole, and the exit surface 201 is further coupled to the primary reflective surface 2011 (the secondary reflective surface 2011 is a structure and is on the surface of the exit surface 201). The generation method is electroplating), and there is a rotating stepped surface 204 near the incident surface 202, and the rotating stepped surface 204 is connected to the dielectric rotating surface 203 and the radiation hole for impedance matching; and the secondary reflector 20 is usually It is composed of all metal, and its curved surface also follows the hyperbolic optical theorem. It has two focal points. One focal point is placed at the focal point of the main disc surface so that the two focal points overlap, while the latter focal point is the phase center position of the feed antenna. And follow all geometrical optics and electromagnetic theories, and the apex of the curved surface itself does not use special design, so the electromagnetic wave path of the feeding antenna produces a shielding effect, which indirectly affects the characteristics of the reflection coefficient of this product, so it is proposed to use hyperbolic metal The vertex of the face is designed with a triangular vertex to guide the electromagnetic wave energy to the two sides of the direct feeding point direction so that the reflected wave does not interfere with the direct radiation direction of the feeding antenna.

As mentioned earlier, the sub-reflector 20 is usually made of all metal and is fixed The structure is relatively complicated, and the complexity is how to reduce the shielding effect of the reflected electromagnetic waves on the main dish surface, and the overall weight of the product is heavier due to all metal, and the airtight function needs to be designed and evaluated by the mechanical engineer, and its airtightness must be designed. Structure, so in this case, a low-loss, high-efficiency dielectric material is also proposed. The dielectric material of the present invention is composed of Rexolite, and its loss coefficient is 0.000666. The material is subjected to a molding process and the raw materials are machined. The hyperboloid curve is formed on the surface of the substrate, and the processed hyperboloid is electroplated or sprayed with metallic paint on the surface, and the curved surface has a metal conductive metal surface layer, and the other end of the raw material is also processed Molding process, the raw material is machined to a circular cylindrical body with the same straight diameter as the feed antenna. The circular cylindrical body has not been specially designed, which will indirectly generate impedance distortion, so the circular cylindrical body is again It is designed stepped so that the impedance change incident on the circular waveguide changes gradually and slowly, which can guide the electromagnetic wave to gently change the electromagnetic wave energy to the secondary reflective disk surface, and improve the phenomenon of impedance change distortion. Moreover, the circular cylindrical body can also be inserted into the aperture of the feed antenna to fix the sub-disk surface, without adding mechanical structure and mechanism, and its plug-in design can also produce a good airtight effect to achieve the antenna feed network. Vacuum operation.

Particularly as shown in Figure 10B, after the secondary reflector 20 is formed through the above-mentioned plastic process, its appearance is like a triangular pyramidal cylinder, and the upper half of the large area of the triangular pyramidal cylinder is the top edge with hyperboloid characteristics. The metal surface of the metal surface is viewed from the front as a circular shape and has a depth, with a deeper small triangular cone in the middle, and from the side view, the curve formed by the depth of the curved surface is a hyperbola conforming to the optical characteristics. And the vertex is a triangular cusp, and the volume of the lower half of the triangular pyramidal cylinder is viewed from the side as a multi-ring-shaped cylinder, and the upper half volume of the triangular pyramidal cylinder and the lower half of the volume are connected by a straight line to form an oblique Angle, so its appearance is similar to a triangular pyramid cylinder as shown in the above description.

In the design of the dish-shaped main reflector 30, Parabolic is used as the reflecting surface, and the cross section of the curved surface is a parabola to effectively gather energy, and the electromagnetic wave is formed into a plane wave to achieve the focusing effect. As a result, a high-gain and high-directional antenna is produced. This feature is very suitable for the needs of millimeter-wave high-gain antennas, that is, high gain and low loss.

The section 14A, as shown in FIG. 14B described principles associated parabola, 14A of FIG containing a line segment L, designated F _1, F ₁ and not on the line segment L, in the plane of the straight distance L is equal to F ₁ point The distance between all moving points P , and the figure formed by these moving points is a parabola. In the process, L is called the directrix and F ₁ is the focal point. The straight line M passing through the vertical directrix of the focal point is the axis of symmetry. The intersection of the symmetry axis and the parabola V is the vertex and V F ₁ is the focal length.

As shown in Figures 2A and 2B, we can place the feed source antenna 10 above the focal point (F), and achieve focusing and multiplying effects to achieve high gain. When designing the dish-shaped main reflector 30, for convenience and Accelerate the antenna simulation speed and simplify its reflection surface. In the full-wave electromagnetic field simulation software, choose Ansys HFSS for simulation. When constructing a paraboloid, it can be constructed using built-in equations, as shown in Figures 15A and 15B. It must be noted that this parameter of the sampling point (N) will affect the precision of the calculation in the millimeter wave frequency band. Therefore, it must be designed so that the distance between the line segment and the real parabola is less than 0.1 wavelength, and in E-Band, this parameter The point is a very important technical key that must be paid attention to.

The parameter of the sampling point (N) is very important, but in actual manufacturing, the problem will not exist, because the main reflective surface is a smooth and continuous reflective curved surface when processing, so there is a problem Only exists in the full-wave electromagnetic field simulation software Ansys HFSS.

Sum up the previous design. Combine the feed source antenna 10, the secondary reflector 20, and the dish-shaped main reflector 30 to perform 3D full-wave simulation to observe the electrical conditions. The structure is constructed by simulation software and then implemented Will be reconstructed using mechanical software.

The size of the dish antenna in this case is the cross-sectional area of the dish-shaped main reflector 30 cm x 30 cm, and the FD Ratio of the reflecting surface is about 0.25, so that the focus of the dish antenna can be on the dish-shaped main reflector 30 In the reflection surface, this point can effectively suppress the generation of the side wave (SLL) of the beam radiation field type, because the energy will be covered by the reflection surface of the dish-shaped main reflector, and the energy can only be radiated in the radiation direction, further reducing The additional diffraction and scattering are at the edge of the block, and the length and width of the main reflector surface corresponds to the E-Band wavelength ratio is very, very large, so it needs to consume a lot of memory and cpu during simulation, also because It requires such a large amount of calculation, which is time-consuming and resource-consuming, and may not be able to complete the simulation smoothly. Therefore, the characteristic function of ansys HFSS is used to set the feed source antenna 10 and the secondary reflector 20 with FEBI and the main reflector. Use physical optics for antenna simulation for PO Region to increase simulation speed and optimize progress.

In the simulation, the four frequency points of E-Band were selected for observation, respectively 71GHz, 76GHz, 81GHz, 86GHz, as shown in Figures 16A to 16D, the feed source antenna 10, the secondary reflector 20, and the dish-shaped primary reflector 30 are combined. The two-dimensional simulated beam radiation pattern of the millimeter-wave high-gain dish antenna. Figures 17A to 17D are the three-dimensional simulated beam radiation pattern of the millimeter-wave high-gain dish antenna, and Figure 18 is the millimeter-wave high-gain dish antenna. The simulated standing wave ratio of the antenna.

The antenna sample test in this case can be divided into beam radiation field test and antenna standing wave ratio test. Figure 19 shows the setup of beam radiation field test, and this test system is an NSI test system, in which the emission source antenna is standard WR12, respectively It is 71GHz, 76GHz, 81GHz, 86GHz, the test results are shown as follows: Figures 20A to 20D are the two-dimensional measurement beam radiation pattern of the millimeter-wave high-gain antenna, and Figures 21A to 21D are the actual millimeter-wave high-gain antenna. Make a three-dimensional measurement beam radiation pattern diagram. Table 3 is a characteristic comparison diagram of millimeter-wave high-gain antennas, and Figure 22 is a measurement standing wave ratio of millimeter-wave high-gain antennas.

When compared with other conventional technologies, the dish antenna structure provided by the present invention has the following advantages:

(1) The dish antenna is used in this case. In addition to using the double-reflector Cassegrain architecture to achieve high gain to meet specifications, the dielectric part is also made of Rexolite material to reduce path loss.

(2) This case is completed by using lightweight, feed-in source antenna to achieve air-tight function, low loss, high efficiency dielectric material.

(3) In the application of millimeter wave communication, in addition to the 5G system platform, the assistive technology industry with this system platform with microwave link technology is a niche field, especially the uniqueness of the market, and the development of its backbone network must catch up. To provide communication bandwidth, which has the advantage of rapid prototyping for network deployment. The antenna types of the present invention are all high-gain antennas with an all-metal structure, so they can carry high-power and other long-distance transmissions of outdoor communication systems. Energy requirements, and the planned dish antenna uses a metal surface to form energy reflection and focus, and a waveguide antenna to form feed, so it has broadband and high-efficiency antenna applications. This antenna technology has the depth of antenna technology and industrial applicability. It is the core antenna technology that the domestic industry and academia need to have when entering the communication system.

The present invention has been disclosed above through the above-mentioned embodiments, but it is not intended to limit the present invention. Anyone familiar with this technical field with ordinary knowledge should understand the aforementioned technical features and implementation of the present invention. For example, without departing from the spirit and scope of the present invention, minor changes and modifications are not allowed. Therefore, the patent protection scope of the present invention shall be subject to the definition of the claims attached to this specification.

10: Feed into the source antenna

20: secondary reflector

30: Dish-shaped main reflector

Claims (20)

A dish-shaped antenna structure includes: a dish-shaped main reflector with a parabolic surface, the parabolic mask has a focal point F; a primary reflector, which is a solid dielectric adapter, essentially having a dielectric rotating surface , An incident surface, an exit surface and a vertex, the dielectric rotating surface is a hyperboloid curved structure, the hyperboloid has a focal point F1 and a focal point F2, and near the vertex is connected to present a conical surface structure An exit surface, the focal point F2 is arranged near the focal point F; and a feed source antenna connected to the parabolic surface and has a radiating hole, the radiating hole is arranged near the focal point F1, the exit surface has a larger diameter than the incident surface, The incident surface is coupled to the radiation hole, and the exit surface is coupled to a primary reflective surface. The dish antenna structure of claim 1, wherein the feed source antenna has an inner wall and an outer wall, the inner wall is coupled to the radiating hole, and the outer wall and the radiating hole are fed through a gradient surface Connected, the inner wall constitutes a waveguide to transmit electromagnetic waves to the radiation hole. The dish antenna structure of claim 2, wherein the feeding gradient surface is a linear rotating surface. The dish antenna structure of claim 3, wherein the bottom diameter of the feeding gradual change surface is the diameter of the outer wall, the upper bottom diameter of the feeding gradual change surface is the diameter of the inner wall, and the height of the linear rotating surface is the The distance from the radiating hole to the bottom of the feeding gradient surface. The dish antenna structure of claim 2, wherein the outer wall has a diameter of 6.0725 mm, the inner wall has a diameter of 3.175 mm, and the distance from the radiation hole to the outer wall is 15 mm. The dish antenna structure of claim 1, wherein the secondary reflective surface is printed on the surface of the exit surface. The dish antenna structure according to claim 1, wherein a rotating stepped surface near the incident surface is connected to the dielectric rotating surface and the radiation hole for impedance matching. The dish antenna structure of claim 1, wherein the solid dielectric adapter is made of Rexolite plastic. The dish antenna structure of claim 1, wherein the dielectric coefficient of the solid dielectric adapter is 2.53. The dish antenna structure of claim 1, wherein the dielectric rotating surface is a linear rotating surface. A dish antenna structure includes: a primary reflector, which is a solid dielectric adapter, substantially has a dielectric rotating surface, an incident surface, an exit surface and a vertex, the dielectric rotating surface is a A curved surface structure of a hyperboloid, the hyperboloid having a focus F1 and a focus F2, and the exit surface showing a conical structure is connected near the vertex, the focus F2 is set near the focus of a parabola; and a feed source antenna , Which is connected to the parabolic surface and has a radiation hole, the radiation hole is arranged near the focal point F1, the exit surface has a diameter larger than the incident surface, the incident surface is coupled to the radiation hole, and the exit surface is coupled with a reflection surface. The dish antenna structure of claim 11, wherein the feed source antenna has an inner wall and an outer wall, the inner wall is coupled to the radiating hole, and the outer wall and the radiating hole are fed through a gradient surface Connected, the inner wall constitutes a waveguide to transmit electromagnetic waves to the radiation hole. The dish antenna structure of claim 12, wherein the feeding gradient surface is a linear rotating surface. The dish antenna structure according to claim 12, wherein the lower diameter of the feeding gradient surface is the diameter of the outer wall, the upper and lower diameter of the feeding gradient surface is the diameter of the inner wall, and the height of the linear rotating surface is the diameter of the inner wall. The distance from the radiating hole to the bottom of the feeding gradient surface. The dish antenna structure of claim 12, wherein the outer wall has a diameter of 6.0725 mm, the inner wall has a diameter of 3.175 mm, and the distance between the radiation hole and the outer wall is 15 mm. The dish antenna structure of claim 11, wherein the secondary reflective surface is printed on the surface of the exit surface. The dish antenna structure according to claim 11, wherein a rotating stepped surface near the incident surface is connected to the dielectric rotating surface and the radiation hole for impedance matching. The dish antenna structure of claim 11, wherein the solid dielectric adapter is made of Rexolite plastic. The dish antenna structure of claim 11, wherein the dielectric coefficient of the solid dielectric adapter is 2.53. The dish antenna structure of claim 11, wherein the dielectric rotating surface is a linear rotating surface.

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