Terahertz integrated lens antenna fed by hollow-core dielectric waveguide
By introducing hollow-core dielectric waveguides and hemispherical transition structures into integrated lens antennas, the problem of insufficient mechanical flexibility of integrated lens antennas is solved, efficient electromagnetic wave transmission and gain improvement is achieved, and its application scenarios are expanded.
Patent Information
- Application Number
- CN202411409729.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-10
- Publication Date
- 2024-12-10
AI Technical Summary
Existing integrated lens antennas lack mechanical flexibility and are difficult to adapt to application scenarios of flexible transmission lines.
A terahertz integrated lens antenna with a feeding power of a hollow core dielectric waveguide is designed, and the connection between the solid core dielectric rod is made to the hollow core dielectric waveguide is introduced into the transition structure to reduce reflection and improve energy transmission efficiency.
The mechanical flexibility of integrated lens antennas is achieved, extending their application range, and improving the gain and directionality of the antenna by reducing reflection.
Smart Images
Figure CN119108825A_ABST
Abstract
Description
Technical Field
[0001] The present application belongs to the field of terahertz antennas, and specifically relates to a hollow-core dielectric waveguide-fed terahertz integrated lens antenna. Background Art
[0002] Integrated lens antenna is an antenna design that combines traditional lens antenna with modern microwave integrated circuit technology. This antenna uses metal or dielectric structures to focus or shape the electromagnetic beam to improve the performance of the antenna. Compared with traditional antennas, integrated lens antennas have the characteristics of small size, light weight, high gain, low side lobe, and good scanning performance.
[0003] In terms of design, an integrated lens antenna is usually composed of one or more lenses combined with one or more antenna arrays. The function of the lens is to focus the electromagnetic waves generated by the antenna array into a narrow beam, thereby improving the directivity of the antenna. The lens includes metal lenses, polymer lenses, silicon lenses, etc., and the focusing of electromagnetic waves is achieved by changing the structure and size of the lens.
[0004] Integrated lens antennas are widely used in many fields, including mobile communications, satellite communications, radar systems, electronic countermeasures, etc. They are particularly suitable for application scenarios that require high gain, high directivity and wide bandwidth.
[0005] Currently, integrated lens antennas are usually fed by metal waveguides and do not have mechanical flexibility. Summary of the invention
[0006] The purpose of the present application is to overcome the defect that the existing integrated lens antenna has no mechanical flexibility.
[0007] In order to achieve the above objectives, the present application proposes a hollow-core dielectric waveguide-fed terahertz integrated lens antenna, the terahertz integrated lens antenna comprising:
[0008] The solid dielectric rod is a cylindrical structure used to transmit electromagnetic waves;
[0009] The transition structure has a shape for focusing electromagnetic waves, one side of which is fixedly connected to the solid dielectric rod and the other side is a plane;
[0010] The elliptical integrated lens antenna is an ellipsoid with a cross section, which passes through a focus of the ellipse and is perpendicular to the major axis; one side of the plane of the transition structure is fixedly connected to the cross section of the elliptical integrated lens antenna, and the center of one side of the plane of the transition structure coincides with the center of the cross section of the elliptical integrated lens antenna.
[0011] As an improvement of the above-mentioned terahertz integrated lens antenna, the terahertz integrated lens antenna further includes:
[0012] The hollow dielectric waveguide is a hollow flexible terahertz transmission line; one end of the solid dielectric rod is inserted into the hollow dielectric waveguide.
[0013] As an improvement of the above-mentioned terahertz integrated lens antenna, the main modes of electromagnetic waves propagating in the hollow dielectric waveguide and the solid dielectric rod are both HE 11 model.
[0014] As an improvement of the above-mentioned terahertz integrated lens antenna, the solid dielectric rod, the hollow dielectric waveguide and the transition structure are made of polytetrafluoroethylene, high-density polyethylene, cycloolefin polymer or cycloolefin copolymer.
[0015] As an improvement of the above-mentioned terahertz integrated lens antenna, the material of the elliptical integrated lens antenna is polytetrafluoroethylene, polystyrene, ceramic, high-resistance silicon or aluminum oxide.
[0016] As an improvement of the above-mentioned terahertz integrated lens antenna, the outer diameter of the transition structure is smaller than the diameter of the cross section of the elliptical integrated lens antenna, and larger than the outer diameter of the solid dielectric rod.
[0017] As an improvement of the above-mentioned terahertz integrated lens antenna, the transition structure is hemispherical.
[0018] Compared with the prior art, the advantages of this application are:
[0019] 1. By designing a solid dielectric rod at the focus, it can be connected to a flexible hollow dielectric waveguide to achieve feeding through the hollow dielectric waveguide, so that the integrated lens antenna can be applied to terahertz systems using flexible transmission lines, greatly increasing mechanical flexibility in actual engineering operations;
[0020] 2. By designing a hemispherical transition structure between the solid dielectric rod and the integrated lens antenna to reduce reflection, the efficiency of energy transition from the dielectric waveguide to the antenna is improved;
[0021] 3. The present application realizes efficient feeding of the integrated lens antenna through a hollow-core dielectric waveguide. Since the hollow-core dielectric waveguide is a flexible transmission line, it has mechanical flexibility. When arranging and moving the antenna, only the antenna needs to be operated without considering the entire system, thereby expanding the practical scope of the integrated lens antenna. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Figure 1 Shown is a schematic diagram of a standard elliptical integrated lens antenna;
[0023] Figure 2 The figure shows a schematic diagram of a novel terahertz integrated lens antenna fed by a hollow-core dielectric waveguide, wherein the shaded part represents the hollow-core dielectric waveguide;
[0024] Figure 3 Shown is a three-dimensional model of a novel terahertz integrated lens antenna fed by a hollow-core dielectric waveguide;
[0025] Figure 4 Dimensions of the embodiment are shown;
[0026] Figure 5 The figure shows the comparison of antenna radiation patterns before and after adding the hemispherical transition structure;
[0027] Figure 6 Shown is the comparison of voltage standing wave ratio before and after adding the hemispherical transition structure. DETAILED DESCRIPTION
[0028] The technical solution of the present application is described in detail below with reference to the accompanying drawings.
[0029] Hollow-core dielectric waveguide is a flexible terahertz transmission line with certain mechanical flexibility and can be bent arbitrarily within a certain range. The present application provides a terahertz integrated lens antenna fed by a hollow-core dielectric waveguide, which has mechanical flexibility in actual engineering operations, facilitates the arrangement and movement of the antenna, and expands the scope of use of the terahertz integrated lens antenna.
[0030] This application is based on the traditional elliptical integrated lens antenna solution. Figure 1 As shown in the figure, this shape is proposed by the optical tracing theory. The eccentricity of the elliptical lens is related to the dielectric constant of the medium. When the point source is located at one of the foci of the ellipse, the spherical wave radiated by the point source can be converted into a local plane wave by the elliptical lens.
[0031] If the length of the minor axis of the ellipse is b, then the length of the major axis is where ε r Represents the relative dielectric constant of the dielectric material. The focal position is
[0032] like Figure 2 , Figure 3 As shown, the present application realizes the transition of electromagnetic waves from the hollow dielectric waveguide to the integrated lens antenna through a solid dielectric rod. The hollow dielectric waveguide is a tubular structure, and the diameter of the solid dielectric rod is equal to the inner diameter of the hollow dielectric waveguide, so it can be inserted into the hollow dielectric waveguide to achieve a stable connection. The transition part can actually be regarded as a solid dielectric waveguide with a radius equal to the outer diameter of the hollow dielectric waveguide. The main mode of electromagnetic wave propagation in the hollow dielectric waveguide and the solid dielectric waveguide is HE. 11 mode, so the electromagnetic wave energy can be fed from the hollow core dielectric waveguide to the integrated lens antenna with very low loss.
[0033] In low-frequency applications, the hollow-core dielectric waveguide can be omitted and directly connected to the solid-core dielectric waveguide for feeding.
[0034] In order to further reduce the reflection of the feeding port, the present application designs a hemispherical transition structure between the solid dielectric rod and the integrated lens antenna. The plane of the hemisphere is close to the plane where the focus of the integrated lens antenna is located, and the center of the circle coincides with the focus of the integrated lens antenna. The spherical surface of the hemisphere is connected to the dielectric rod. The hemispherical structure can also be regarded as an anti-hemispherical antenna to perform a certain amount of focusing on electromagnetic waves, and because the discontinuity of the structure is reduced, the reflection of the antenna is reduced, and the loss of electromagnetic wave energy fed from the hollow dielectric waveguide to the integrated lens antenna is reduced, which is beneficial to improve the gain of the integrated lens antenna.
[0035] The hemispherical transition structure may also be replaced by a transition structure of other shapes (such as a stepped shape) that can play a role in focusing electromagnetic waves.
[0036] Example 1
[0037] A 500 GHz flexible probe is used as an example for explanation.
[0038] This embodiment is applied to a 500 GHz nondestructive testing system, where a conventional antenna is replaced with a section of hollow-core dielectric waveguide, and a novel integrated lens antenna fed by the dielectric waveguide is connected at the end.
[0039] Hollow dielectric waveguides should be made of materials that have low absorption of terahertz waves and have a certain degree of flexibility, such as polytetrafluoroethylene, high-density polyethylene, cycloolefin polymers, cycloolefin copolymers, etc. In this embodiment, polytetrafluoroethylene is preferred. Common materials for integrated lens antennas include polytetrafluoroethylene, polystyrene, ceramics, high-resistance silicon, alumina, etc. Among them, materials with high dielectric constants can have better beam shaping and energy coupling effects, but they will also bring higher reflection losses within the lens. Considering the performance and the transition with the dielectric waveguide, the lens material is also preferably polytetrafluoroethylene.
[0040] like Figure 4 As shown, the dimensions of the elliptical integrated lens antenna are determined. The relative dielectric constant ε of polytetrafluoroethylene at 500 GHz r =2.07. Taking the minor axis length as b=2mm, the major axis length is calculated. Distance from focus to ellipse center The size of the elliptical integrated lens antenna is determined by actual needs. If higher gain and better directivity are required, the size can be enlarged proportionally.
[0041] The plane of the hemispherical transition structure is close to the plane where the focus of the integrated lens antenna is located, the center of the circle coincides with the focus of the integrated lens antenna, and the radius r is 0.5 mm.
[0042] The transmission window of the hollow dielectric waveguide has nothing to do with the inner diameter, but only with the thickness of the dielectric layer. In this embodiment, the hollow dielectric waveguide is a polytetrafluoroethylene tube with an inner diameter of 0.15 mm and an outer diameter of 0.3 mm, so the radius of the solid dielectric rod is also 0.15 mm.
[0043] like Figure 5 , Figure 6 As shown, the simulation results show that the new integrated lens antenna fed by the hollow dielectric waveguide has a maximum gain of 26.1dBi, and the voltage standing wave ratio in the working frequency band is less than 1.16. If the hemispherical transition structure is removed, the maximum gain drops to 25.6dBi, and the maximum voltage standing wave ratio in the working frequency band rises to 1.46. This shows that the present application can be used as part of a terahertz flexible probe in a 500GHz non-destructive testing system with good performance, and the hemispherical transition structure can also effectively reduce the reflection of the antenna and increase the gain. In this application, the mechanical flexibility of the system is greatly improved, and the flexibility of the dielectric waveguide can be used to bypass obstacles, achieve work in a small space or detect objects behind obstacles; when scanning the target, it is also possible to move only the antenna without moving the entire system, showing the good engineering practical value of the present invention.
[0044] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present application and are not intended to limit it. Although the present application is described in detail with reference to the embodiments, a person skilled in the art should understand that any modification or equivalent replacement of the technical solution of the present application does not depart from the spirit and scope of the technical solution of the present application and should be included in the scope of the claims of the present application.
Claims
1. A hollow dielectric waveguide-fed terahertz integrated lens antenna, characterized in that: The terahertz integrated lens antenna comprises: The solid dielectric rod is a cylindrical structure used to transmit electromagnetic waves; A transition structure having a shape for focusing electromagnetic waves, one side of which is fixedly connected to a solid dielectric rod and the other side of which is a plane; and The elliptical integrated lens antenna is an ellipsoid with a cross section, which passes through a focus of the ellipse and is perpendicular to the major axis; one side of the plane of the transition structure is fixedly connected to the cross section of the elliptical integrated lens antenna, and the center of one side of the plane of the transition structure coincides with the center of the cross section of the elliptical integrated lens antenna.
2. The hollow-core dielectric waveguide-fed terahertz integrated lens antenna according to claim 1, characterized in that: The terahertz integrated lens antenna further comprises: The hollow dielectric waveguide is a hollow flexible terahertz transmission line; one end of the solid dielectric rod is inserted into the hollow dielectric waveguide.
3. The hollow-core dielectric waveguide-fed terahertz integrated lens antenna according to claim 2, characterized in that: The main modes of electromagnetic waves propagating in the hollow dielectric waveguide and the solid dielectric rod are both HE 11 model.
4. The hollow-core dielectric waveguide-fed terahertz integrated lens antenna according to claim 2, characterized in that: The solid dielectric rod, the hollow dielectric waveguide and the transition structure are made of polytetrafluoroethylene, high-density polyethylene, cycloolefin polymer or cycloolefin copolymer.
5. The hollow-core dielectric waveguide-fed terahertz integrated lens antenna according to claim 1, characterized in that: The material of the elliptical integrated lens antenna is polytetrafluoroethylene, polystyrene, ceramic, high-resistance silicon or aluminum oxide.
6. The hollow-core dielectric waveguide-fed terahertz integrated lens antenna according to claim 1, characterized in that: The outer diameter of the transition structure is smaller than the diameter of the cross section of the elliptical integrated lens antenna, and is larger than the outer diameter of the solid dielectric rod.
7. The hollow-core dielectric waveguide-fed terahertz integrated lens antenna according to claim 1, characterized in that: The transition structure is hemispherical.