Terahertz wave band inclined beam planar waveguide slot antenna

Abstract

The invention discloses an inclined beam planar waveguide slot antenna of a terahertz wave band, and belongs to the field of radio frequency front-end devices. The first metal layer, the dielectric layer and the second metal layer are stacked from bottom to top, and the metal through hole is communicated with the two layers of metal and penetrates through the dielectric layer. Wherein the first metal layer is an integral rectangular metal ground; the dielectric layer is an integral rectangular dielectric layer; the second metal layer is an antenna main radiation layer and comprises a rectangular CPW signal ground, a ball-rod-shaped CPW signal line and a rectangular guide patch; the upper edge of the CPW signal line and the CPW signal ground form an input port, and the lower edge of the CPW signal line is about one half of the working wavelength away from the CPW signal ground to form a gap to radiate electromagnetic waves. When an excitation signal is accessed to the input port, the main radiation structure generates an inclined wave beam of which the maximum radiation direction is in the 50-degree direction of a pitching surface. The inclined beam planar waveguide slot antenna has the characteristics of high working frequency band, high front-to-back ratio, simple structure and easiness in integration.

Description

Technical Field

[0001] The present invention relates to a tilted beam planar waveguide slot antenna based on a coplanar waveguide structure, combined with a substrate-like integrated waveguide structure, and is mainly used in low-altitude communication and satellite communication in the terahertz band and reconfigurable antenna structures in the corresponding bands, belonging to the field of radio frequency front-end devices. Background Art

[0002] The terahertz antenna focusing on the sixth-generation mobile communication technology has important research value. Due to its high integration, higher operating frequency band and smaller structural size, it has great advantages in low-altitude, vacuum high-speed communication and other fields.

[0003] In order to better integrate antennas on mobile devices, or conform to aircraft and achieve beam steering, there have been many studies on low-profile antennas. Planar microstrip antennas are one of the most popular structures. In recent years, there have been many studies on millimeter wave bands, but there are not many studies on terahertz bands. Compared with complex phased arrays, reconfigurable pattern antennas are often smaller in size, but can also achieve beam switching. In 2023, several researchers from Xidian University proposed a circularly polarized microstrip antenna for 5G communication, which operates at 3.4-3.7GHz; Meng Xin and others from Qingdao University proposed an end-fire antenna operating at 3.67-3.88GHz in 2022, and used coplanar and normal phase rotation unit arrangements to achieve pattern reconstruction; Liang Ying and others from Beijing University of Aeronautics and Astronautics proposed a microstrip antenna with a main frequency of 77GHz and a large capacitance characteristic (ELP) in 2021. It can be used for phased arrays, but its side-firing characteristics do not match the miniaturized reconfigurable antenna. Summary of the invention

[0004] In order to solve the problems existing in the background technology, the present invention designs a tilted beam planar waveguide slot antenna operating in the terahertz band, which can meet the requirement of 50° tilt of the beam pointing. The designed antenna has the characteristics of simple structure, convenient design, high front-to-back ratio, high integration, and high operating frequency band.

[0005] The present invention adopts the following technical solutions to achieve the above technical effects:

[0006] A terahertz-band tilted beam planar waveguide slot antenna comprises a first metal layer, a dielectric layer, an antenna radiation layer stacked from bottom to top, and a metal through hole connecting the first metal layer and the antenna radiation layer and penetrating the dielectric layer.

[0007] The first metal layer is a rectangular metal ground 1;

[0008] The dielectric layer is a rectangular dielectric layer 2;

[0009] The antenna radiation layer includes a rectangular CPW signal ground 4, a CPW signal line 5, and a rectangular guide patch 6. A trumpet-shaped slot is opened on the CPW signal ground, and the two vertices of the bottom edge of the CPW signal ground opposite to the trumpet mouth are provided with triangular chamfers; the CPW signal line is located on the center line of the trumpet-shaped slot, and its top edge and the CPW signal ground form an input port, and there is a gap between the bottom edge and the bottom of the trumpet-shaped slot to radiate electromagnetic waves; the rectangular guide patch is smaller than half a working wavelength, is located in the direction opposite to the trumpet mouth, and has a spacing greater than zero with the CPW signal ground.

[0010] The metal through hole 3 is cylindrical, and a plurality of metal through holes are distributed around the antenna radiation layer, wherein two front through holes are located in front of the lead patch.

[0011] Furthermore: the antenna radiation layer is used as a radiation structure, and its rectangular guide patch guides the tilted beam, and a plurality of metal through holes form an electric wall to constrain the ground diffraction wave.

[0012] Further: the CPW signal line 5 includes an input section, a neck section and a matching section connected in sequence; wherein the length of the input section matches the input end of the trumpet-shaped slot, and the width of the neck section is smaller than the input section and the matching section.

[0013] Furthermore: the trumpet-shaped slot includes a rectangular input end and a trapezoidal end, the rectangular input end is connected to the upper bottom of the trapezoidal end, and the central axis of the two coincides with the central axis of the CPW signal line 5.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] Compared with the background technology, the present invention has the following advantages:

[0016] a) The operating frequency band covers 320GHz to 350GHz;

[0017] b) The structure is simple, with only three layers from bottom to top;

[0018] c) The planar structure has a low profile and is easy to integrate, process and conform to the shape. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the dielectric layer of the waveguide slot antenna.

[0020] Figure 2 This is a schematic diagram of the first metal layer of the waveguide slot antenna.

[0021] Figure 3 It is a schematic diagram of the metal through hole array of the waveguide slot antenna.

[0022] Figure 4 is a front view of the second metal layer of the waveguide slot antenna;

[0023] Figure 5 is the H-plane radiation pattern of the waveguide slot antenna;

[0024] Figure 6 is the E-plane radiation pattern of the waveguide slot antenna;

[0025] Figure 7 is the return loss of the waveguide slot antenna. DETAILED DESCRIPTION

[0026] Below, the present invention is further described in conjunction with the accompanying drawings.

[0027] The following is combined with Figure 1-7 The specific implementation modes of the present invention are further described in detail with reference to the accompanying drawings and examples.

[0028] The invention discloses a tilted beam planar waveguide slot antenna working in the terahertz band, comprising a first metal layer, a dielectric layer, a second metal layer stacked from bottom to top, and a metal through hole connecting the two metal layers and penetrating the dielectric layer.

[0029] The first metal layer is an overall rectangular metal ground 1;

[0030] The dielectric layer is an overall rectangular dielectric layer 2;

[0031] Attach Figure 2 Taking the second metal layer of the waveguide slot antenna as an example, it is the main radiation structure of the antenna, which is composed of a CPW signal ground 4, a CPW signal line 5, and a guide patch 6, wherein the rectangular CPW signal ground is made of metal, a trumpet-shaped slot is opened in the middle of the signal ground, and a triangular chamfer is opened at each of the two vertices of the lower edge of the metal signal ground to reduce useless radiation loss; the CPW signal line is in the shape of a ball stick as a whole, and is made of the same material as the CPW signal ground. Its upper edge and the CPW signal ground form an input port with an equivalent impedance of 50Ω, and its lower edge and the CPW signal ground form a wide gap with a length of about half an operating wavelength, and the "handle" width of the "ball stick" is used for impedance matching; the guide patch 6 is a rectangular metal with a width slightly less than half an operating wavelength, and the center of the structure is about 0.3 free space wavelengths away from the lower edge of the CPW signal ground.

[0032] The metal through hole 3 is cylindrical, with a radius much smaller than the working wavelength and a length the same as the thickness of the dielectric layer. The metal through hole group is distributed circumferentially along the second metal layer. The two front through holes are located in front of the guide patch, with a center spacing of approximately half a working wavelength, and the center spacing of the remaining through holes is less than a quarter of the working wavelength.

[0033] Attach Figures 1 to 3Taking the metal through holes as an example, each of them is cylindrical and its radius is much smaller than the working wavelength. The metal through hole group is distributed circumferentially along the second metal layer, forming a metal electric wall around the main radiation structure to constrain the ground diffraction wave and standardize the radiation pattern. Two front-end through holes are set in front of the guide patch. The center distance between the two through holes is about half of the working wavelength, where the diffraction wave can be released.

[0034] The tilted beam planar waveguide slot antenna structure working in the terahertz band selects a material and size combination for example description (the following data is in micrometers):

[0035] In order to reduce the loss, the first and second metal layers are made of gold, the dielectric layer is made of quartz glass, and the metal through hole is also made of gold;

[0036] when Figures 1 to 3 The dimensions of the structure are:

[0037] Size R1 = 10, size 21 = 110, size 22 = 30, size 23 = 100, size 24 = 420, size 25 = 50, size 26 = 20, size 27 = 80, size 28 = 100, size 29 = 320;

[0038] when Figure 4 The dimensions of the structure are:

[0039] Size 7 = 461.2, size 8 = 61.2, size 9 = 31.2, size 10 = 10, size 11 = 100, size 12 = 80, size 13 = 290, size 14 = 690, size 15 = 30, size 16 = 10, size 17 = 310, size 18 = 401.2, size 19 = 290, size 20 = 150;

[0040] The length of the rectangular metal ground and dielectric layer of the first metal layer is 1210 and the width is 600. When the thickness of the first and second metal layers are both 1, the RF signal enters the antenna through the input port and can generate an inclined beam that deviates from the positive direction of the Z axis by about 50°. At this time, the radiation pattern of the antenna is as follows: Figure 5 and Figure 6 , the maximum gain reaches 6.4dB, and the return loss is Figure 7 , showing that the antenna's return loss is significantly less than -12dB in the frequency range of 320 to 350GHz.

[0041] The above is just an example. If you want to obtain a tilted beam antenna at different center frequencies, you can adjust different parameters according to the specific implementation method, such as adjusting the gap length to change the operating frequency band, adjusting the position and size of the guide patch, and the distribution of metal through holes to change the radiation pattern, adjusting the length and width of the CPW signal line to reduce the loss, and the opening size of the CPW ground to adjust the impedance matching.

[0042] It should be understood that the above description of the specific implementation methods of this patent is only an exemplary description listed to facilitate ordinary technicians in the field to understand the patent scheme, and does not imply that the scope of protection of this patent is limited to these individual examples. Ordinary technicians in this field can fully understand the technical scheme of this patent and, without any creative work, obtain more specific implementation methods by combining technical features, replacing some technical features, adding more technical features, etc. to the examples listed in this patent. All these specific implementation methods are within the scope of the claims of this patent. Therefore, these new specific implementation methods should also be within the scope of protection of this patent.

[0043] In addition, for the purpose of simplifying the description, this patent may not list some common specific implementation schemes, which are naturally conceivable to ordinary technicians in this field after understanding the technical solution of this patent. Obviously, these solutions should also be included in the scope of protection of this patent.

Claims

1. A terahertz-band tilted beam planar waveguide slot antenna, comprising a first metal layer, a dielectric layer, an antenna radiation layer stacked from bottom to top, and a metal through hole connecting the first metal and the antenna radiation layer and penetrating the dielectric layer, characterized in that: The first metal layer is a rectangular metal ground (1); The dielectric layer is a rectangular dielectric layer (2); The antenna radiation layer comprises a rectangular CPW signal ground (4), a CPW signal line (5), and a rectangular guide patch (6). The CPW signal ground is provided with a trumpet-shaped slot, and two vertices of the bottom edge of the CPW signal ground directly opposite to the trumpet mouth are provided with triangular chamfers; the CPW signal line is located on the center line of the trumpet-shaped slot, and its top edge and the CPW signal ground form an input port, and a gap is provided between the bottom edge and the bottom of the trumpet-shaped slot to radiate electromagnetic waves; the rectangular guide patch has a size less than half a working wavelength, is located in the direction directly opposite to the trumpet mouth, and has a spacing greater than zero with the CPW signal ground. The metal through hole (3) is cylindrical, and a plurality of metal through holes are distributed around the antenna radiation layer, wherein two front through holes are located in front of the lead patch.

2. The terahertz-band tilted-beam planar waveguide slot antenna according to claim 1, characterized in that: The antenna radiation layer is used as a radiation structure, and its rectangular guiding patch guides the tilted beam, and a plurality of metal through holes form an electric wall to constrain the ground diffraction wave.

3. The terahertz-band tilted-beam planar waveguide slot antenna according to claim 1, characterized in that: The CPW signal line (5) comprises an input section, a neck section and a matching section which are connected in sequence; wherein the length of the input section matches the input end of the trumpet-shaped slot, and the width of the neck section is smaller than the input section and the matching section.

4. The terahertz-band tilted-beam planar waveguide slot antenna according to claim 1, characterized in that: The trumpet-shaped slot comprises a rectangular input end and a trapezoidal end, wherein the rectangular input end is connected to the upper bottom of the trapezoidal end, and the central axis of the two coincides with the central axis of the CPW signal line (5).

Images