Continuous scanning substrate integrated waveguide leaky-wave antenna with double-row slot structure

Abstract

The invention provides a double-row slot structure continuous scanning substrate integrated waveguide leaky-wave antenna which comprises a dielectric plate, a top metal layer, a metal grounding plate, a metal probe, an outer conductor and a radiator structure, the upper layer and the lower layer of the dielectric plate are attached to the top metal layer and the metal grounding plate respectively, and the radiator structure is composed of a double-row A-shaped slot. The double rows of A-shaped gaps are arranged on the top metal layer, the top metal layer is composed of a plurality of transversely arranged periodic structures, a width-gradually-changed 50-ohm converter and a 50-ohm microstrip line, any periodic structure contains two A-shaped gaps, the 50-ohm converter is respectively connected with the 50-ohm microstrip line and the radiator structure, an outer conductor is connected with the metal grounding plate, and an inner conductor is connected with the metal grounding plate. And the metal probe is connected with the top metal layer. The leaky-wave antenna can solve the problems that a traditional leaky-wave antenna is small in scanning angle and an open stop band exists in the scanning process.

Description

Technical Field

[0001] The present invention relates to the technical field of wireless communication applications, and in particular to a double-row slot structure continuous scanning substrate integrated waveguide leaky wave antenna. Background Art

[0002] In recent years, with the continuous development of science and technology, wireless communication technology has also been booming. Mobile communications have been pursuing the transmission of more stable and accurate data in a shorter time. Antennas in wireless communication devices bear the important responsibility of transmitting and receiving signals. Improving the performance of antennas makes data transmission safer.

[0003] With the rapid development of modern communications, the field of modern communications is becoming more and more extensive. People's requirements for wireless systems such as radar, communication, measurement and control, and energy transmission are increasing day by day, and the research on antenna technology is constantly facing new challenges. Driven by military and commercial applications for a long time, antennas have differentiated into different forms according to various application fields and realized different functions. Among many antennas, leaky wave antennas have attracted much attention from academia and industry for their unique radiation characteristics. Leaky wave antennas have frequency scanning capabilities, strong directivity, and a wide operating frequency band, and are easy to integrate into the feed network. Substrate integrated waveguide is a new type of waveguide structure developed in recent years. As a planar transmission line, substrate integrated waveguide has the characteristics of low loss and easy integration and manufacturing. It not only continues the advantages of traditional closed waveguides, but also makes the original bulky and costly three-dimensional waveguides planarized and miniaturized, which can be used in the design of leaky wave antennas.

[0004] Leaky wave antenna is a type of traveling wave antenna. By controlling the energy leakage rate of the leaky wave antenna, people can design it with high gain, high scanning rate, circular polarization, frequency scanning and other functions. Although the substrate integrated waveguide double-row slot stacking structure is more complicated in design, it can disturb more surface currents in the same period, save space, and has certain research value. Summary of the invention

[0005] The object of the present invention is to provide a double-row slot structure continuous scanning substrate integrated waveguide leaky wave antenna, aiming to solve the problems of small scanning angle and open stop band in the scanning process of traditional leaky wave antenna.

[0006] The present invention provides a double-row slot structure continuous scanning substrate integrated waveguide leaky wave antenna, which comprises a dielectric plate, a top metal layer, a metal ground plate, a metal probe, an outer conductor, and a radiator structure, wherein:

[0007] The upper and lower layers of the dielectric plate are respectively bonded to the top metal layer and the metal ground plate; the radiator structure is composed of a double row of A-shaped gaps, and the double row of A-shaped gaps are arranged on the top metal layer; the top metal layer is composed of a plurality of transversely arranged periodic structures, a 50-ohm converter with a gradient width, and a 50-ohm microstrip line; any of the periodic structures contains two A-shaped gaps; the 50-ohm converter is respectively connected to the 50-ohm microstrip line and the radiator structure; the outer conductor is connected to the metal ground plate; and the metal probe is connected to the top metal layer.

[0008] Furthermore, the position corresponding to the center of each A-shaped gap is located on the midline of the unit periodic structure, the length of the unit periodic structure is 15 mm, and the width of the unit periodic structure is 14 mm.

[0009] Furthermore, metallized vias are provided on both sides of the top metal layer, and the double-row A-shaped gaps are located between the metallized vias on both sides.

[0010] Furthermore, any one of the periodic structures contains 15 of the metallized vias, the radius of the metallized via is 0.3 mm, and the distance between the centers of any two adjacent metallized vias on the same side is 1 mm.

[0011] Furthermore, the distance between the center of the metallized via and the nearest edge thereof is 1.5 mm, and the distance between the centers of any two directly opposite metallized vias on both sides is 11 mm.

[0012] Furthermore, any of the A-shaped gaps consists of two oblique grooves and one curved groove, the length of any of the oblique grooves is 3.8 mm, the width of any of the oblique grooves is 1 mm, the distance between the center point of any of the A-shaped gaps and the edge of its nearest side is 5 mm, the distance between the center point of any of the A-shaped gaps and the midline of the periodic structure in the horizontal direction is 1.44 mm, and the center points of the two oblique grooves in the same A-shaped gap are 2.88 mm apart in the horizontal direction.

[0013] Furthermore, the center points of the oblique grooves of any two A-shaped gaps located on both sides and corresponding to each other are 4 mm apart in the vertical direction.

[0014] Furthermore, the inclined groove of any of the A-shaped gaps is rotated, and the angle between any of the inclined grooves and the horizontal direction is 55°, and the angle between any of the inclined grooves and the vertical direction is 35°.

[0015] Furthermore, the curved groove is composed of two inclined short grooves. A short groove with a width of 1 mm is etched at an angle of 95° at a distance of 1.74 mm from the lower left corner of one of the long oblique sides in the A-shaped gap. At the same time, a short groove is etched at the corresponding position of the other long oblique side in a symmetrical manner until the short grooves on both sides overlap and connect.

[0016] Furthermore, the width of the 50-ohm microstrip line is 2 mm and the length is 3.5 mm; the width of one end of the 50-ohm converter is 2 mm and the width of the other end is 4 mm; the length of the 50-ohm converter is 4 mm.

[0017] In summary, according to the above-mentioned double-row slot structure continuous scanning substrate integrated waveguide leaky wave antenna, two A-shaped slots are set in a periodic structure to realize the continuous scanning substrate integrated waveguide leaky wave antenna, which has the advantages of good broadband planarity, low cost, easy integration of components, high gain and large scanning angle. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the front structure of the continuous scanning substrate integrated waveguide leaky wave antenna with double-row slot structure in the first embodiment of the present invention;

[0019] Figure 2 It is a schematic diagram of the back structure of the continuous scanning substrate integrated waveguide leaky wave antenna with double-row slot structure in the first embodiment of the present invention;

[0020] Figure 3 It is a schematic diagram of the side structure of the continuous scanning substrate integrated waveguide leaky wave antenna with double-row slot structure in the first embodiment of the present invention;

[0021] Figure 4 The S parameter curve of the double-row slot structure continuous scanning substrate integrated waveguide leaky wave antenna prepared in the second embodiment of the present invention;

[0022] Figure 5 This is a graph showing the variation of the main beam pointing angle with frequency within the working range of the double-row slot structure continuous scanning substrate integrated waveguide leaky wave antenna prepared in the second embodiment of the present invention.

[0023] Explanation of symbols: 1-outer conductor; 2-metal probe; 3-dielectric plate; 4-top metal layer; 5-A-shaped gap; 6-metallized via; 7-metal ground plate.

[0024] The following specific implementation manner will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Unless otherwise defined, the technical terms or scientific terms used herein should be understood by people with general skills in the field to which the present invention belongs. "Including" and similar words used in this article mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects.

[0026] Embodiment 1

[0027] See also Figures 1 to 3 The first embodiment of the present invention provides a double-row slot structure continuous scanning substrate integrated waveguide leaky wave antenna, which includes a dielectric plate 3, a top metal layer 4, a metal ground plate 7, a metal probe 2, an outer conductor 1, and a radiator structure, wherein:

[0028] The upper layer of the dielectric plate 3 is tightly fitted with the top metal layer, and the lower layer of the dielectric plate 3 is tightly fitted with the metal grounding plate 7. In addition, the radiator structure is composed of a double row of A-shaped gaps 5, and the double row of A-shaped gaps 5 are arranged on the top metal layer 4. By etching the double row of A-shaped gaps 5 on the top metal layer 4, it can be used to disturb the surface current.

[0029] The top metal layer 4 is composed of a plurality of transversely arranged periodic structures, a 50-ohm converter with a gradient width, and a 50-ohm microstrip line, and each periodic structure contains two A-shaped slots 5. In some embodiments, the line has a total of 12 periods, and the top metal layer 4 is composed of 12 transversely arranged periods and a microstrip converter with a gradient width and a 50-ohm microstrip line, and the 50-ohm converter is respectively connected to the 50-ohm microstrip line and the radiator structure to achieve impedance matching, thereby forming a double-row slot structure continuous scanning substrate integrated waveguide leaky wave antenna.

[0030] In addition, the metal probe 2 and the outer conductor 1 form a feeding structure, the outer conductor 1 is connected to the metal ground plate 7, the metal probe 2 is connected to the top metal layer, and the 50 ohm microstrip line is fed through the metal probe 2, so that the antenna is fed by the feeding structure in a side-feeding manner.

[0031] In addition, the position corresponding to the center of each A-shaped gap 5 is located on the midline of the unit periodic structure. The length of the unit periodic structure is 15 mm, and the width of the unit periodic structure is 14 mm.

[0032] In addition, metallized vias 6 are provided on both sides of the top metal layer 4, and double rows of A-shaped gaps 5 are located between the metallized vias 6 on both sides, and any periodic structure contains 15 metallized vias 6, and the radius of the metallized vias 6 is 0.3 mm. The center distance between any two adjacent metallized vias 6 on the same side is 1 mm, and the center distance between the metallized via 6 and the nearest side edge is 1.5 mm. A total of 180 metallized vias 6 need to be made, and the distance between the center of any two opposite metallized vias 6 on both sides is 11 mm.

[0033] In addition, any A-shaped slot 5 is composed of two oblique grooves and one curved groove, and there are two A-shaped slots 5 in one period. For the above A-shaped slot 5, the positional relationship of the two oblique grooves is that the length of the oblique groove is 3.8 mm and the width is 1 mm. The center point is 5 mm away from the edge of the nearest side of the substrate integrated waveguide, and the distance from the center line of the unit period structure in the horizontal direction is 1.44 mm, that is, the center points of the two oblique grooves are 2.88 mm apart in the horizontal direction, showing a symmetrical relationship with the center line of the unit period.

[0034] In addition, there are two A-shaped slots 5 stacked up and down in one period. For the lower A-shaped slot 5, the length of the inclined slot is also 3.8 mm and the width is 1 mm. It is 1.44 mm horizontally from the center line of the unit period, and its center point is 5 mm away from the edge of the nearest side of the substrate integrated waveguide, that is, the center points of the long slots of the two A-shaped slots 5 are 4 mm apart in the vertical direction. During the manufacturing process, the upper A-shaped slot 5 can be moved down by 4 mm to copy the A-shaped slot 5 of the lower structure.

[0035] In addition, the inclined groove of any A-shaped gap 5 is rotated, and the angle between any inclined groove and the horizontal direction is 55°, and the angle between any inclined groove and the vertical direction is 35°.

[0036] In addition, the straight line of the standard A in the A-shaped gap 5 is replaced by a curved straight line, and the curved groove in the A-shaped gap 5 is composed of two inclined short grooves. A short groove with a width of 1 mm is etched at an angle of 95° at a distance of 1.74 mm from the lower left corner of the long hypotenuse on the left side of the A-shaped gap 5, and at the same time, a short groove is also etched at the corresponding position of the right hypotenuse in a symmetrical manner until the short grooves on both sides overlap and connect.

[0037] In addition, regarding the design of the 50-ohm converter and the 50-ohm microstrip line, the width of the 50-ohm microstrip line is 2mm and the length is 3.5mm; the width of the 50-ohm converter is 2mm at one end and 4mm at the other end. The length of the 50-ohm converter is 4mm. The gradient width design can achieve impedance matching.

[0038] Preferably, the medium of the dielectric plate 3 is a solid medium; the dielectric plate 3 is rectangular; the metal floor and the transmission line are planar structures and are close to the dielectric plate 3; the structure in the antenna is made of metal material and copper metal is selected, which can be printed by circuit board printing.

[0039] Embodiment 2

[0040] The second embodiment of the present invention further provides a method for preparing a double-row slot structure continuous scanning substrate integrated waveguide leaky wave antenna, which is used to prepare the double-row slot structure continuous scanning substrate integrated waveguide leaky wave antenna of the first embodiment, specifically:

[0041] The top metal layer is laid along the dielectric plate, which is 195 mm long and 14 mm wide. A 180 mm long rectangular top metal layer is made on the upper surface of the dielectric plate, with both sides 7.5 mm away from the edge of the dielectric plate, leaving space for making the microstrip converter.

[0042] The top metal layer is divided into 12 periods, each period is 15mm, and two A-shaped gaps are made in a single period. The A-shaped gaps are symmetrical about the midline of the period. A total of 24 A-shaped gaps are etched on the top metal layer. The A-shaped gaps in a unit period are 4mm apart in the vertical direction, and the A-shaped gaps in adjacent periods are 15mm apart. The center of the A-shaped gap in each period is on the midline of the period and is symmetrical about the midline of the period.

[0043] A ground plane with a length of 195 mm and a width of 14 mm is made on the lower surface of the dielectric plate. Then, metallized vias are made on the dielectric plate, 15 per cycle, and the center of the first metallized via is 0.5 mm away from the narrow side of the top metal layer and 1.5 mm away from the wide side of the top metal layer. A total of 180 metallized vias need to be made.

[0044] Microstrip converters are manufactured on the left and right sides of the top metal layer according to claim 7, and the radiator structure is completed, and finally the feeding structure is connected.

[0045] In this embodiment, the dielectric plate used is Rogers RO4003 (tm), and its dielectric constant ε r =3.55, the thickness of the dielectric plate 1 is h=0.762mm, the width is W=14mm, and the loss tangent is 0.0027.

[0046] The S11 reflection coefficient of the antenna manufactured in this embodiment is as follows: Figure 4 As shown. Figure 4 It can be seen that in the frequency range of 9.2GHz to 14.3GHz, the S11 value is stably maintained below -10dB, meeting the standards required for industrial production and having good performance.

[0047] Figure 5 : is the radiation pattern of this embodiment within the working range, and the horizontal axis is the main beam pointing angle. Figure 5 The corresponding frequencies of the middle beam increase from left to right, showing the changes of the main beam within the operating frequency range of 9.2 GHz to 14.3 GHz, reflecting the frequency scanning characteristics of the antenna prepared in this embodiment. In the entire working range, it can be continuously scanned from -66° to +20°, with a total scanning range of 86°, realizing the continuous scanning function of the leaky wave antenna; on the other hand, when the frequency is 10.5 GHz, the gain does not attenuate at the position where the main beam pointing angle is 0°, and the open stop band is successfully eliminated.

[0048] In summary, according to the above-mentioned double-row slot structure continuous scanning substrate integrated waveguide leaky wave antenna, two A-shaped slots are set in a periodic structure to realize the continuous scanning substrate integrated waveguide leaky wave antenna, which has the advantages of good broadband planarity, low cost, easy integration of components, high gain and large scanning angle.

[0049] Although the embodiments of the present invention are described in detail above, it is obvious to those skilled in the art that various modifications and variations can be made to these embodiments. However, it should be understood that such modifications and variations are within the scope and spirit of the present invention as described in the claims. Moreover, the present invention described herein may have other embodiments and may be implemented or realized in a variety of ways.

Claims

1. A double-row slot structure continuous scanning substrate integrated waveguide leaky wave antenna, characterized in that: It includes a dielectric plate, a top metal layer, a metal ground plate, a metal probe, an outer conductor, and a radiator structure, wherein: The upper and lower layers of the dielectric plate are respectively bonded to the top metal layer and the metal ground plate; the radiator structure is composed of a double row of A-shaped gaps, and the double row of A-shaped gaps are arranged on the top metal layer; the top metal layer is composed of a plurality of transversely arranged periodic structures, a 50-ohm converter with a gradient width, and a 50-ohm microstrip line; any of the periodic structures contains two A-shaped gaps; the 50-ohm converter is respectively connected to the 50-ohm microstrip line and the radiator structure; the outer conductor is connected to the metal ground plate; and the metal probe is connected to the top metal layer.

2. The double-row slot structure continuous scanning substrate integrated waveguide leaky wave antenna according to claim 1, characterized in that: The center of each A-shaped gap is located on the midline of the unit periodic structure. The length of the unit periodic structure is 15 mm, and the width of the unit periodic structure is 14 mm.

3. The double-row slot structure continuous scanning substrate integrated waveguide leaky wave antenna according to claim 1, characterized in that: Metallized vias are arranged on both sides of the top metal layer, and the double-row A-shaped gaps are located between the metallized vias on both sides.

4. The double-row slot structure continuous scanning substrate integrated waveguide leaky wave antenna according to claim 3, characterized in that: Any of the periodic structures contains 15 metallized vias, the radius of the metallized via is 0.3 mm, and the distance between the centers of any two adjacent metallized vias on the same side is 1 mm.

5. The double-row slot structure continuous scanning substrate integrated waveguide leaky wave antenna according to claim 4, characterized in that: The center of the metallized via is 1.5 mm away from the nearest edge of one side, and the distance between the centers of any two directly opposite metallized vias on both sides is 11 mm.

6. The double-row slot structure continuous scanning substrate integrated waveguide leaky wave antenna according to claim 1, characterized in that: Any of the A-shaped gaps consists of two oblique grooves and one curved groove, the length of any of the oblique grooves is 3.8 mm, the width of any of the oblique grooves is 1 mm, the distance between the center point of any of the A-shaped gaps and the edge on its nearest side is 5 mm, the distance between the center point of any of the A-shaped gaps and the midline of the periodic structure in the horizontal direction is 1.44 mm, and the center points of the two oblique grooves in the same A-shaped gap are 2.88 mm apart in the horizontal direction.

7. The double-row slot structure continuous scanning substrate integrated waveguide leaky wave antenna according to claim 6, characterized in that: The center points of the oblique grooves of any two A-shaped gaps located on both sides and corresponding to each other are 4 mm apart in the vertical direction.

8. The double-row slot structure continuous scanning substrate integrated waveguide leaky wave antenna according to claim 6, characterized in that: The inclined groove of any of the A-shaped gaps is rotated, and the angle between any of the inclined grooves and the horizontal direction is 55°, and the angle between any of the inclined grooves and the vertical direction is 35°.

9. The double-row slot structure continuous scanning substrate integrated waveguide leaky wave antenna according to claim 6, characterized in that: The curved groove consists of two inclined short grooves. A short groove with a width of 1 mm is etched at an angle of 95° at a distance of 1.74 mm from the lower left corner of one of the long oblique sides in the A-shaped gap. At the same time, a short groove is etched symmetrically at the corresponding position of the other long oblique side until the short grooves on both sides overlap and connect.

10. The double-row slot structure continuous scanning substrate integrated waveguide leaky wave antenna according to claim 1, characterized in that: The width of the 50-ohm microstrip line is 2 mm and the length is 3.5 mm; the width of one end of the 50-ohm converter is 2 mm and the width of the other end is 4 mm; the length of the 50-ohm converter is 4 mm.

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