Air waveguide array antenna with sawtooth structure

Abstract

The present application relates to an air waveguide array antenna with sawtooth structure. An antenna device comprises: a meandering waveguide meandering back and forth around a longitudinal axis; one or more horn antennas, each comprising a feeding waveguide and an open radiator, a hollow inner core of the feeding waveguide being in communication with a hollow channel of the meandering waveguide through a slot in a first surface of the meandering waveguide, the open radiator having a horn-shaped hollow cavity, a first end of the hollow cavity being in communication with the hollow inner core of the feeding waveguide, a second end of the hollow cavity being in communication with an external environment, wherein the horn shape has a specific slope; and a sawtooth-shaped protrusion positioned on both sides of the horn antenna and extending along the longitudinal axis, a cross section of the sawtooth-shaped protrusion perpendicular to the longitudinal axis being sawtooth-shaped, a face on which a bottom edge of the sawtooth-shaped protrusion lies being coplanar with a horn aperture plane of the horn antenna, wherein structural parameters of the sawtooth-shaped protrusion are configured in combination with the slope of the open radiator to cause the antenna device to generate a specific radiation field.

Description

TECHNICAL FIELD

[0001] The present invention relates to the field of antenna devices, and more specifically, to an air waveguide array antenna with a sawtooth structure. BACKGROUND

[0002] Some devices, such as radar systems, use one or more antennas to transmit and receive signals, which can be used to detect and track objects. The radiation pattern is an important parameter of an antenna. The shape of the radiation pattern determines the application of the antenna. Therefore, precisely controlling the radiation pattern of the antenna can expand the application scenarios of the radar system, so that the radiation pattern can be better adapted to a specific application scenario. For example, some specific scenarios can require a radar system that can generate a narrow beam width or a biased beam pointing to detect objects within a specific field of view, such as in the driving path of a vehicle. The ability to generate a wide beam with a desired coverage, a narrow beam with good focusing, or a beam that is skewed to a specific direction in such systems needs to be improved. SUMMARY

[0003] This document describes techniques, devices, and systems for an air waveguide array antenna with a sawtooth structure. The present invention relates to an antenna device comprising a meander waveguide, one or more horn antennas, and a sawtooth-shaped boss. The meander waveguide meanders back and forth around a longitudinal axis, the meander waveguide comprising a meandering hollow channel, a first surface for defining the hollow channel, and one or more slots through the first surface. Each of the one or more horn antennas comprises a feed waveguide, a hollow inner core of the feed waveguide being in communication with the hollow channel of the meander waveguide through the slot in the first surface of the meander waveguide, such that at least a portion of a signal propagating in the hollow channel of the meander waveguide can enter the feed waveguide of the horn antenna through the slot, and an open-ended radiator configured as a hollow cavity with a horn shape, a first end of the hollow cavity being in communication with the hollow inner core of the feed waveguide, and a second end of the hollow cavity being in communication with an external environment, such that the signal from the feed waveguide can be emitted into the external environment through the open-ended radiator, wherein the horn shape has a specific slope. The sawtooth-shaped boss is positioned on both sides of the horn antenna and extends along the longitudinal axis, a cross section of the sawtooth-shaped boss perpendicular to the longitudinal axis is sawtooth-shaped, and a face on which a bottom edge of the sawtooth-shaped boss lies is coplanar with a horn aperture plane of the horn antenna, wherein the structural parameters of the sawtooth-shaped boss are configured in combination with the slope of the open-ended radiator to cause the antenna device to generate a specific radiation field.

[0004] This summary introduces simplified concepts related to an air waveguide array antenna with a sawtooth structure, which are further described in the detailed description and the accompanying drawings. This summary is not intended to identify essential features of the claimed subject matter, nor is it intended for determining the scope of the claimed subject matter. BRIEF DESCRIPTION OF DRAWINGS

[0005] To further clarify the above and other advantages and features of the present embodiments, a more particular description of embodiments of the application will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. It is appreciated that these drawings depict only typical embodiments of the application and are therefore not to be considered limiting of its scope.

[0006] Furthermore, the primary connections or relative positioning of the various parts illustrated in the drawings are not necessarily drawn to scale, and the description herein of the various embodiments of the application can include other sizes and shapes.

[0007] Details of one or more aspects of air waveguide array antennas with sawtooth structure are described herein with reference to the following drawings. Like numbers in the figures refer to like components throughout the specification:

[0008] Figure 1 An exploded structural schematic diagram of an air waveguide array antenna with sawtooth structure according to the present application is shown;

[0009] Figure 2a A 3D structural schematic diagram of an air waveguide array antenna with sawtooth structure according to a first embodiment of the present application is shown;

[0010] Figure 2b A cross-sectional view of an air waveguide array antenna with sawtooth structure according to a first embodiment of the present application is shown;

[0011] Figure 2c E-plane radiation patterns of an air waveguide array antenna with sawtooth structure according to a first embodiment of the present application and an air waveguide array antenna without sawtooth structure are shown;

[0012] Figure 2d E-plane radiation patterns of an air waveguide array antenna with sawtooth structure according to a first embodiment of the present application and a conventional forward-looking automotive radar binary microstrip array antenna are shown;

[0013] Figure 3a A 3D structural schematic diagram of an air waveguide array antenna with sawtooth structure according to a second embodiment of the present application is shown;

[0014] Figure 3b A cross-sectional view of an air waveguide array antenna with sawtooth structure according to a second embodiment of the present application is shown;

[0015] Figure 3c E-plane radiation patterns of an air waveguide array antenna with sawtooth structure according to a second embodiment of the present application and an air waveguide array antenna without sawtooth structure are shown;

[0016] Figure 4A first alternative embodiment of a boss comprising an air waveguide array antenna with a sawtooth structure according to the present application is shown;

[0017] Figure 5 A second alternative embodiment of a boss comprising an air waveguide array antenna with a sawtooth structure according to the present application is shown;

[0018] Figure 6 A schematic view of a system comprising an air waveguide array antenna with a sawtooth structure according to the present application is shown;

[0019] Figure 7 An example method for manufacturing an air waveguide array antenna with a sawtooth structure according to the present application is shown. DETAILED DESCRIPTION

[0020] The following detailed description is made with reference to the accompanying drawings. The drawings are for purposes of illustration only and the claimed subject matter is not limited to the specific embodiments illustrated. Embodiments described are illustrative of specific examples to provide an understanding of the present claimed subject matter. However, the application should not be limited in its application to these specific framework examples. Many modifications and variations will occur to those of ordinary skill in the art upon reading this description. Accordingly, the application should not be limited to the specific examples described in this disclosure.

[0021] In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the various described embodiments. However, it will be apparent to one skilled in the art that the various embodiments described can be practiced without these specific details. In other instances, well-known structures have not been described in detail in order to avoid obscuring the aspects of the various embodiments. Unless otherwise defined, terms used in this disclosure have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

[0022] Embodiments of the present application are exemplary implementations or examples. References in the specification to "an embodiment", "one embodiment", "some embodiments", "various embodiments", or "other embodiments" indicate that the particular feature, structure, or characteristic being described is included in at least one embodiment of the technology, but not necessarily all embodiments of the technology. The various appearances of "an embodiment", "one embodiment”, or "some embodiments” or "other embodiments” do not necessarily all refer to the same embodiments. Elements or aspects from one embodiment can be combined with elements or aspects of another embodiment.

[0023] SUMMARY

[0024] Radar systems are an important sensing technology for obtaining information about the surrounding environment in many industries, including the automotive industry. Some application scenarios, e.g., automotive applications, can require radar systems that provide a narrow beam width or a biased beam pointing to detect objects within a specific field of view, e.g., in the driving path of a vehicle, to meet the requirements of specific scenarios for specific beams. Embodiments of the present invention can feed a horn array antenna through a waveguide, add protrusions of specific shapes on both sides of the array axis of the horn array antenna to direct the electromagnetic radiation of the horn antenna, to generate a narrower beam width or a biased beam pointing with better directivity than a normal waveguide aperture radiator, to meet the requirements of specific scenarios for specific applications.

[0025] The waveguide can comprise an air waveguide. Alternatively, other dielectrics can be included in the waveguide. The waveguide of the present invention can preferably comprise a meandered rectangular waveguide with a hollow channel, the meandering similar to a square wave shape can avoid grating lobes of the array antenna. Electromagnetic waves or other types of waves can enter the waveguide from an opening on one side of the meandered waveguide. The other end of the waveguide can be configured as a closed wall. The upper surface of the meandered waveguide that defines the hollow channel can include one or more feed slots (or feed openings). A plurality of horn antennas can be connected (preferably, equidistantly) on the upper surface of the meandered waveguide to form a linear array, electromagnetic waves or other types of waves flow through the horn antennas inside the meandered waveguide to radiate outward; there is a row of sawtooth-shaped protrusions on both sides of the array axis of the horn array antenna to direct electromagnetic waves or other types of waves, so as to focus them into a narrow beam or a biased beam pointing to produce a specific antenna pattern. The structural parameters of the sawtooth, the structural parameters of the horn, or the positional relationship between the two can be adjusted as needed to change the shape of the horn antenna radiation beam to form a biased beam or a narrow-beam-focused antenna pattern.

[0026] The described waveguide can be particularly advantageous for use in automotive contexts, e.g., detecting objects in the road in the driving path of a vehicle. A narrow beam width allows a radar system of a vehicle to detect objects in a specific field of view (e.g., directly in front of the vehicle); a biased beam allows a radar system of a vehicle to detect objects in a specific field of view (e.g., in the area to the left front, right front, left rear, or right rear of the vehicle) to adopt different radiation detection fields for different detection scenarios. As an example and not a limitation, a radar system placed near the front of a vehicle can use a narrow beam width to focus on detecting objects directly in front of the vehicle, rather than objects positioned to the sides of the vehicle.

[0027] The above is only one example of the described air waveguide array antenna with a sawtooth structure. The present disclosure also describes other examples and implementations of the present invention.

[0028] Example apparatus

[0029] Figure 1 An air waveguide array antenna device 102 including a sawtooth structure is shown in accordance with the present application. The antenna device 102 can include a waveguide 103, a horn antenna 104, and a sawtooth-shaped protrusion 109.

[0030] As mentioned above, the waveguide 103 can preferably be an air waveguide. Air waveguide antennas are a new technology in automotive radar applications for reasons of manufacturing and cost, but still have many advantages over microstrip or SIW slot antennas manufactured on a radio frequency board, such as low loss, high efficiency, higher antenna array aperture utilization, etc. The waveguide 103 can preferably be a meandering waveguide. For example, the waveguide 103 can meander back and forth around a longitudinal axis 106. The waveguide 103 can include a hollow channel 105, wherein the longitudinal axis 106 or a parallel axis in the direction of the longitudinal axis 106 can be configured to pass through the hollow channel 105. More specifically, the waveguide 103 can be a hollow meandering waveguide with one or more serially connected square wave shapes as shown. Figure 1 The electromagnetic wave other types of waves (may be collectively referred to as signals) 124 can propagate in the hollow channel 105 of the waveguide 103. The meandering waveguide 103 can include metal, plastic, and a combination of plastic and metal.

[0031] In a preferred embodiment, the hollow channel 105 forms a rectangular opening 107 on one end (first end) of the longitudinal axis direction 106 and a closed wall 108 at the opposite end (second end, opposite to the first end). The signals 124 can enter the hollow channel 105 of the waveguide 103 through the opening 107, be reflected by the closed wall 108 after reaching the closed wall 108, and propagate again in the hollow channel 105 to form a standing wave.

[0032] The meandering waveguide 103 can include an upper surface (first surface) 110 for defining the hollow channel 105. The upper surface 110 of the hollow channel 105 can include one or more slots or openings 111 passing therethrough. The signals (including electromagnetic waves or other types of waves) propagating in the hollow waveguide 103 can exit the waveguide 103 through one or more slots 111 in the upper surface 110 of the meandering waveguide 103 into the array horn antenna 104. In a preferred embodiment, the hollow waveguide 105 forms a periodic square wave shape arranged along the longitudinal axis direction 106, which is folded back and forth around the longitudinal axis 106. The longitudinal axis 106 or a parallel axis in the direction of the longitudinal axis 106 passes through the hollow channel 105 in the longitudinal direction. In a more preferred embodiment, the meandering waveguide 103 is formed by a plurality of identical square wave shapes connected in series along the longitudinal axis 106 direction, and the distance between two adjacent square wave shapes in the longitudinal axis 106 direction is less than one wavelength of the signals.

[0033] Antenna assembly 102 may include one or preferably multiple horn antennas 104 (multiple antenna elements in an array can provide higher gain and directivity than a single antenna element can achieve). Multiple horn antennas 104 may be arranged in an array along the longitudinal axis 106 on the upper surface 110 of the hollow waveguide 105. The number and aperture of the horn antennas can be designed according to different desired beamforms. Each slot 111 on the upper surface 110 of the hollow channel 105 may be configured to couple one horn antenna 104 from the array of horn antennas 104 to provide a signal. The array of horn antennas 104 may be uniformly distributed between the rectangular opening 107 and the enclosed wall 108. Preferably, the multiple horn antennas 104 have the same shape. The number of horn antennas 104 is equal to the number of complete square wave shapes in the bent waveguide 103. The spacing between adjacent horn antennas 104 is equal to the spacing between adjacent square wave shapes.

[0034] More specifically, one antenna element of the array horn antenna 104 may consist of a feed waveguide 112 and an open radiator 113. The open radiator 113 may be configured as a horn-shaped radiating cavity. The feed waveguide 112 may have a hollow core that communicates with the hollow channel 105 of the bent waveguide 103 via a slot 111 in the first surface 110 of the bent waveguide 103, such that at least a portion of other types of electromagnetic waves propagating in the hollow channel 105 of the bent waveguide 103 can enter or couple to the feed waveguide 112 of the horn antenna 104 through the slot 111. The open radiator 113 of the horn antenna 104 is configured as a horn-shaped hollow cavity, the first end of which ( Figure 1 The lower end shown is connected to the hollow core of the feed waveguide 112, and the second end of the hollow cavity ( Figure 1 The upper end (as shown) is connected to the external environment, allowing electromagnetic waves and other types of waves from the feed waveguide 112 to be radiated into the external environment through the open radiator 113. For example... Figure 1 As shown, the horn shape of the open radiator 113 can have a specific slope.

[0035] The shape of the aperture surface 114 of the horn antenna 104's aperture radiator 113 can be selected according to the desired radiation pattern. For example, the aperture surface 114 can be rectangular to form a linear polarization pattern. The aperture surface 114 can be circular to form a circular polarization pattern. The aperture surface 114 can also be elliptical to form an elliptical polarization pattern. The cross-sectional shape of the aperture waveguide 112 and the opening shape of the coupling slot 111 can be the same as or similar to the shape of the aperture surface 114 of the aperture radiator 113, and can also be rectangular, circular, or elliptical accordingly. Furthermore, the horn aperture surface 114 of the aperture radiator 113 can have specific dimensions, as shown in the following combination. Figure 2a , Figure 2b ,Figure 3a and Figure 3b are described in more detail.

[0036] The antenna device 102 can further include a sawtooth-shaped protrusion 109. The sawtooth-shaped protrusion 109 can be positioned on both sides of the aperture plane 114 of the open radiators 113 of the horn antenna 104 and extend along the longitudinal axis 106, thus being parallel to the longitudinal axis 106. As will be described in connection with the following Figure 2b and Figure 3b As can be more clearly seen, a cross-section of the sawtooth-shaped protrusion 109 perpendicular to the longitudinal axis 106 can be sawtooth-shaped. Also as can be more clearly seen in connection with the following Figure 2b and Figure 3b As can be more clearly seen, a plane on which the bottom edge of the sawtooth-shaped protrusion 109 can be coplanar with the horn aperture plane 114 of the horn antenna 104. In the design of the present application, the structural parameters of the sawtooth-shaped protrusion 109 in combination with the slope of the open radiators 113 can be configured such that the antenna device 102 is capable of generating a specific radiation field.

[0037] The sawtooth-shaped protrusion 109 can be metallic or a plastic material plated with a metal on the surface. The sawtooth-shaped protrusion 109 can be a sawtooth-like triangle in a cross-section perpendicular to the longitudinal axis 106. The sawtooth-shaped protrusion 109 can change the radiation field of the arrayed horn antenna 104 when the arrayed horn antenna 104 radiates the spatial signal 124. By designing and optimizing one or more of the structural parameters of the sawtooth-shaped protrusion 109, its distance from the edge of the aperture plane 114, the slope of the horn-shaped open radiators 113, the shape or size of the aperture plane 114 of the horn-shaped open radiators 113, the antenna device 102 can be made to produce a desired antenna radiation pattern. The following will describe the antenna radiation pattern of a narrow-beam focusing or a beam pointing, respectively, by designing one or more of the structural parameters in connection with two specific embodiments.

[0038] Figure 2a An air waveguide array antenna 102-1 with a sawtooth structure according to a first embodiment of the present application is shown. The antenna 102-1 can be an example of the antenna 102 and have the features of the antenna 102 as described above. The arrayed horn antenna 104 can radiate simultaneously, producing a horizontally polarized antenna pattern.

[0039] As Figure 2aAs shown, the arrayed horn antennas 104 can be uniformly distributed between the rectangular opening 107 and the closed wall 108 and along the longitudinal axis 106. The arrayed horn antennas 104 can be disposed on the upper surface 110 of the folded waveguide. Each of the antenna units in the arrayed horn antennas 104 can be identical, i.e., the feed waveguide 112 and the aperture radiator 113 of each antenna unit are identical, and two adjacent antenna units are spaced apart by a distance 200 along the longitudinal axis 106, so that the antenna device 102-1 produces a specific directional pattern. In a preferred embodiment, the distance 200 can be designed to be less than one wavelength of the signal (e.g., electromagnetic radiation) 124 reaching the opposite end 108 of the hollow channel 105, so as to eliminate the effect of grating lobes. The positions of the arrayed horn antennas 104 can be determined by constructing a model of the antenna 104 and optimizing the model to produce a desired antenna directional pattern. In order to ensure that each of the antenna units of the arrayed horn antennas 104 is fed in phase, the distance 200 between adjacent antenna units is kept uniform.

[0040] Figure 2b As shown Figure 2a A cross-sectional view of the air waveguide array antenna 102-1 with the sawtooth structure shown in the plane 201 perpendicular to the longitudinal axis 106, the cross-sectional view passing through the midpoint of the edge of the aperture face 114 of the aperture radiator 113 of a certain antenna unit in the arrayed horn antennas 104 parallel to the longitudinal axis 106. As shown Figure 2b As shown, the relevant structural parameters in the cross-sectional view are as follows: the aperture edge length 202 of the aperture face 114 in the plane 201, the distance 203 from the midpoint of the edge of the aperture face 114 on the left side (first end point) to the vertex of the triangular cross-section of the sawtooth-shaped boss 109, the perpendicular distance 204 from the vertex of the triangular cross-section to the bottom edge, the distances 205 and 206 from the vertex of the triangular cross-section to the projection points of the bottom edge, and the slope of the aperture radiator 113. One or more of the above structural parameters can be adjusted to achieve a desired radiation pattern. For example, a model of the antenna can be constructed, and the specific values of one or more of the above structural parameters can be changed to optimize the model of the antenna to produce a desired radiation pattern. The shapes and structural parameters of the sawtooth-shaped bosses 109 on the left and right sides of the aperture radiator 113 can be consistent or inconsistent, preferably consistent, to achieve more accurate control.

[0041] Figure 2c As shown Figure 2a A comparison of the directional pattern of the air waveguide array antenna with the sawtooth structure shown in the E-plane (parallel to the plane of the radiation electric field) with the directional pattern of the antenna without the sawtooth structure in the E-plane. Among them, Figure 2a The sawtooth-shaped boss 109 of the air waveguide array antenna 102-1 with the sawtooth structure shown in the cross-sectional view 201 is generally an isosceles triangle, the vertex of which is chamfered, and the aperture radiator 113 has a specific slope.

[0042] As Figure 2b shown, the specific setting of the sawtooth-shaped protrusions 109 in combination with the specific slope of the arrayed horn antennas 104 can change the radiation of the arrayed horn antenna 104, as Figure 2c shown, the radiation pattern has a narrower beam width and also a greater gain between about -20° to +20°, thus better directivity and better focusing effect, enabling the radar system to focus the radiation pattern of the corresponding antenna on a narrower field of view where the object of interest is located. As an example, the antenna device 102-1 thus arranged can be arranged in a radar system near the front of a vehicle to use the narrow beam width to focus on detecting objects directly in front of the vehicle. However, the antenna device 102-1 can not be limited to use in a vehicle, but can be used in any system that requires a directional pattern with better focusing as Figure 2c shown.

[0043] Figure 2d The Figure 2a shown air waveguide array antenna with sawtooth structure has a comparison of the E-plane (parallel to the plane of the radiated electric field) directional pattern with the E-plane directional pattern of a binary microstrip array antenna commonly used in current forward application vehicle-mounted radars. As a forward radar application, the radiation pattern of the antenna device 102-1 has a wider beam width than the conventional antenna, enabling the radar system to have a wider angular coverage. As an example, a radar system placed near the front of a vehicle can not only detect objects directly in front by focusing, but also have better target detection capability for scenarios such as other vehicles in the side lane inserting into its own lane.

[0044] Figure 3a An air waveguide array antenna 102-2 with sawtooth structure according to a second embodiment of the present application is shown. The antenna 102-2 can be an example of the antenna 102 and has the features of the antenna 102 as described above. The arrayed horn antennas 104 can radiate simultaneously, producing an antenna directional pattern that is horizontally polarized. In comparison with the structure Figure 2a shown, Figure 3a the cross section of the protrusions 109 is a non-isosceles triangle, and the inclination of the arrayed horn antennas 104 and the aperture size also change.

[0045] As Figure 3aAs shown, the array horn antennas 104 can be uniformly distributed between the rectangular opening 107 and the closed wall 108 and along the longitudinal axis 106. The array horn antennas 104 can be arranged on the upper surface 110 of the bent waveguide. Each of the array horn antennas 104 can be identical, i.e., the feeding waveguide 112 and the opening radiator 113 of each of the array horn antennas 104 are identical, and two adjacent array horn antennas 104 are spaced apart by a distance 200 along the longitudinal axis 106, so that the antenna device 102-2 generates a specific radiation pattern. In a preferred embodiment, the distance 200 can be designed to be less than one wavelength of the signal 124 reaching the opposite end 108 of the hollow channel 105, so as to eliminate the effect of grating lobes. The positions of the array horn antennas 104 can be determined by constructing a model of the antenna 104 and optimizing the model to generate a desired radiation pattern of the antenna 104. In order to ensure that each of the array horn antennas 104 is fed in phase, the distance 200 between two adjacent array horn antennas 104 is kept constant.

[0046] Figure 3b As shown Figure 3a A cross-sectional view of the air waveguide array antenna 102-2 with the sawtooth structure shown in the plane 201 perpendicular to the longitudinal axis 106, the cross-sectional view passing through the midpoint of the edge of the aperture plane 114 of the opening radiator 113 of a certain array horn antenna 104 parallel to the longitudinal axis 106. As shown Figure 3b As shown, the relevant structural parameters in the cross-sectional view are as follows: the aperture edge length 302 of the aperture plane 114 in the plane 201, the distance 303 from the midpoint of the projection of the top vertex of the cross-sectional triangular shape of the sawtooth-shaped protrusion 109 on the bottom edge to the left edge (first end point) of the aperture plane 114, the distance 304 of the perpendicular line from the top vertex of the triangular shape to the bottom edge, the distances 305 and 306 from the projection point of the top vertex of the triangular shape on the bottom edge to the other two vertices of the triangular shape, and the slope of the opening radiator 113. One or more of the above structural parameters can be adjusted to achieve a desired radiation pattern. For example, a model of the antenna can be constructed, and the specific values of one or more of the above structural parameters can be changed to optimize the model of the antenna to generate a desired radiation pattern. The shapes and structural parameters of the sawtooth-shaped protrusions 109 on the left and right sides of the opening radiator 113 can be consistent or inconsistent, and are preferably consistent to achieve more accurate control.

[0047] Figure 3c As shown Figure 3a The comparison of the radiation pattern of the air waveguide array antenna with the sawtooth structure shown in the E-plane (parallel to the plane of the radiation electric field) with the radiation pattern of the antenna without the sawtooth structure in the E-plane. Among them, Figure 3a The cross-section of the sawtooth-shaped protrusion 109 of the air waveguide array antenna 102-2 with the sawtooth structure shown in the cross-sectional view 201 is a non-isosceles triangle with the left oblique side shorter than the right oblique side, the top vertex of the triangle is formed as a chamfer, and the slope of the opening radiator 113 is substantially perpendicular at 90°.

[0048] As Figure 3b shown, the particular setting of the sawtooth protrusion 109 in combination with the particular slope (90° vertical) of the aperture radiator 113 can change the radiation of the array horn antenna 104, as Figure 3c shown, with the beam pointing of the radiation pattern deflected, for example Figure 3c shown, from 0° indicated by the dashed line to about -25° indicated by the solid line, and with a greater gain in the -25° direction, thus enabling the radar device to focus the radiation pattern of the corresponding antenna on the field of view orientation where the object of potential interest is located. As an example, a radar system placed near the corners of a vehicle can use such an antenna with beam pointing deflection to better focus on targets on the vehicle's own adjacent lane. However, the antenna device 102-2 can not be limited to use in vehicles, but can be used in any system that requires a directional pattern with pointing deflection as Figure 3c shown.

[0049] For exemplary purposes, two antenna device examples are shown as Figure 2a and Figure 3a However, it can be understood that based on the concept of the present invention, other shapes of antenna radiation patterns can be obtained by designing one or more of the structural parameters of the sawtooth protrusion 109, its distance from the edge of the aperture surface 114, the structural parameters of the horn-shaped aperture radiator 113, including the slope.

[0050] Example boss

[0051] Figure 4 A first alternative embodiment of a protrusion 109 of an air waveguide array antenna with a sawtooth structure according to the present invention is shown. The protrusion 109 can be as Figure 4The illustrated tapered trapezoid. The tapered trapezoid can have a small upper base length with a large difference from the lower base length. The trapezoid can be an isosceles trapezoid or a non-isosceles trapezoid. When the boss 109 is a tapered trapezoid, factors affecting the radiation pattern of the antenna 102 can include one or more of the following: structural parameters of the boss 109 including the upper base length 407 and the lower base length (405+406) of the tapered trapezoid, the height 404 of the tapered trapezoid, the inclination of the first and second oblique sides of the tapered trapezoid (where the first inclination can be characterized by the distance 405 and the height 404, the second inclination can be characterized by the distance 406 and the height 404, the distance 405 is the distance from the projection B of the midpoint A of the upper base on the lower base to the vertex C, the distance 406 is the distance from the projection B of the midpoint A of the upper base on the lower base to the vertex D), the distance 403 from the projection point B of the center point A of the upper base of the tapered trapezoid to the first endpoint of the horn aperture surface 114, the slope of the opening radiator 113, the aperture size 402, shape of the aperture surface 114. One or more of the above structural parameters can be adjusted to achieve a desired radiation pattern. The shapes of the sawtooth-shaped bosses 109 on the left and right sides of the opening radiator 113 can be consistent or inconsistent, preferably consistent. The vertices of the tapered trapezoid can form a chamfer. Preferably, the tapered trapezoid is not configured with an edge chamfer at the corners of the base. Further preferably, the radius of the edge chamfer is no more than 30% of the minimum side length of the tapered trapezoid.

[0052] Figure 5 A second alternative embodiment of the boss 109 according to the present application is shown comprising an air waveguide array antenna with a sawtooth structure. The boss 109 can be a rectangle as shown. Figure 5 When the boss 109 is a rectangle, factors affecting the radiation pattern of the antenna 102 can include one or more of the following: structural parameters of the boss 109 including the height 504 of the rectangle, the length 505 of the rectangle, the distance 503 from the projection point B’ of the midpoint of the bottom side of the rectangle to the first endpoint of the horn aperture surface 114, the slope of the opening radiator 113, the aperture size 502, shape of the aperture surface 114. One or more of the above structural parameters can be adjusted to achieve a desired radiation pattern. The shapes of the sawtooth-shaped bosses 109 on the left and right sides of the opening radiator 113 can be consistent or inconsistent, preferably consistent. The vertices of the rectangle can form a chamfer. Preferably, the rectangle is not configured with an edge chamfer at the corners of the base. Further preferably, the radius of the edge chamfer is no more than 30% of the minimum side length of the rectangle.

[0053] For the purpose of example, in conjunction with Figure 4 and Figure 5Alternative embodiments of the protrusion 109 are described. However, more cross-sectional shapes of the protrusion can be conceived. The desired radiation pattern can be obtained by adjusting one or more of the parameters of the protrusion 109 having a certain cross-sectional shape, the position of the protrusion 109 and the opening radiator 113, the aperture side length or shape of the aperture face 114, the slope of the opening radiator 113, etc.

[0054] Example system

[0055] Figure 6 A schematic diagram of a system 100 comprising an air waveguide array antenna with a sawtooth structure according to the present invention is shown.

[0056] The system 100 can comprise an antenna device 102 (comprising 102-1 or 102-2) as described above. The antenna device 102 can comprise a bent waveguide 103, a horn antenna 104, and a sawtooth protrusion 109. The system can further comprise a control circuit 130. The control circuit 130 can be configured for transmitting or receiving signals via the antenna device 102, e.g. the system 100 can control the antenna 102 to capture signals coming into the waveguide 103 from the air via the control circuit 130, or can control the antenna 102 to transmit signals in the waveguide 103 to the outside via the control circuit 130. The device 130 can further be configured for processing signals to perform functions.

[0057] The system 100 can be a radar system, an ultrasound system, or other system configured for receiving signals. The system 100 can be, but is not limited to, part of a vehicle, such as an autonomous car. Parts of the system 100 can be integrated onto a printed circuit board or a substrate.

[0058] Example method

[0059] Figure 7 An example method 700 for manufacturing an air waveguide array antenna with a sawtooth structure according to the present invention is depicted. The method 700 is shown as a set of operations 702-706 performed in (but not necessarily limited to) the order or combination of operations shown or described. Further, any of the operations 702-706 can be repeated, combined, or reorganized to provide other methods. In the following discussed sections, reference can be made to the entities detailed above, only for example. The techniques of the present invention are not limited to being performed by one entity or multiple entities.

[0060] At 702, an air waveguide array antenna with a zigzag structure, such as the air waveguide array antenna with a zigzag structure 102, 102-1, or 102-2, is formed. The air waveguide array antenna with a zigzag structure can include the meander waveguide 103, the array horn antenna 104, the zigzag-shaped protrusion 109. The meander waveguide 103, the array horn antenna 104, the zigzag-shaped protrusion 109 can be printed, punched, etched, cut, machined, cast, molded, or formed in some other way. The antenna can be processed in several parts and then fixed by external or internal fasteners without affecting the performance of the antenna. The fasteners can include, but are not limited to, plastic fasteners, metal fasteners, or double-sided adhesives. The adhesives can include, but are not limited to, dielectrics, epoxies, glues, or double-sided tapes, etc. Alternatively, the parts of the antenna can be integrally manufactured. The processing tolerance should not be greater than ±1%. In addition, in the preferred embodiments of the present application, the fillet radius of all edge chamfers, if any, should not exceed 30% of the minimum edge length.

[0061] At 704, the array antenna with a zigzag structure can be integrated into a system, such as the system 100 of Figure 6 . The system 100 can include, for example, a radar system. The system 100 can be applied in a vehicle, but is not limited to a vehicle.

[0062] At 706, electromagnetic signals can be transmitted or received via the array antenna with a zigzag structure. For example, the antenna 102 can be controlled via the control circuit 130 to capture electromagnetic signals from the air into the waveguide 103, or the antenna 102 can be controlled via the control circuit 130 to emit electromagnetic signals in the waveguide 103 to the outside.

[0063] Some specific embodiments of the air waveguide array with a zigzag structure, apparatuses, and systems are described above. It should be understood that the descriptions of positions, orientations in this specification (for example, up, down, left, right, etc.) are made in conjunction with the embodiments in the drawings, and thus are a kind of relative position description. In embodiments where the placement direction of the device, apparatus is opposite or different from the direction shown in the figure, these position descriptions can be changed accordingly.

[0064] Those skilled in the art can make appropriate modifications and adjustments to the above specifically described embodiments without departing from the spirit and essence of the present application. Therefore, it is intended that the claimed subject matter not be limited to the specific examples disclosed, but also include all implementations falling within the scope of the appended claims and their equivalents.

[0065] Some examples of the present application are provided below:

[0066] Example 1. An antenna apparatus, comprising:

[0067] a meandering waveguide meandering back and forth around a longitudinal axis, the meandering waveguide comprising:

[0068] a meandering hollow channel;

[0069] a first surface for defining the hollow channel; and

[0070] one or more slots through the first surface;

[0071] one or more horn antennas, each of the one or more horn antennas comprising:

[0072] a feed waveguide, a hollow inner core of the feed waveguide being in communication with the hollow channel of the meandering waveguide through a slot in the first surface of the meandering waveguide, such that at least a portion of a signal propagating in the hollow channel of the meandering waveguide is able to enter the feed waveguide of the horn antenna through the slot; and

[0073] an open radiator configured as a hollow cavity having a horn shape, a first end of the hollow cavity being in communication with the hollow inner core of the feed waveguide, a second end of the hollow cavity being in communication with an external environment, such that a signal from the feed waveguide is able to be emitted into the external environment through the open radiator, wherein the horn shape has a specific slope; and

[0074] a sawtooth-shaped protrusion positioned on both sides of the horn antenna and extending along the longitudinal axis, a cross-section of the sawtooth-shaped protrusion perpendicular to the longitudinal axis being sawtooth-shaped, a face on which a bottom edge of the sawtooth-shaped protrusion lies being coplanar with a horn aperture plane of the horn antenna, wherein structural parameters of the sawtooth-shaped protrusion are configured in combination with the slope of the open radiator such that the antenna device generates a specific radiation field.

[0075] Example 2. The antenna device of Example 1, wherein a shape of the cross-section of the sawtooth-shaped protrusion comprises one of a triangle, a sharpened trapezoid, or a rectangle.

[0076] Example 3. The antenna device of any of the above examples, wherein,

[0077] when the shape of the cross-section of the sawtooth-shaped protrusion is a triangle, the structural parameters of the sawtooth-shaped protrusion comprise:

[0078] a perpendicular distance from a first vertex of the triangle to a bottom edge of the triangle;

[0079] a distance from a projection point of the first vertex of the triangle on the bottom edge to a second vertex of the triangle; and / or

[0080] a distance between a projection point of the first vertex of the triangle on the base and a third vertex of the triangle,

[0081] when the shape of the cross section of the serrated boss is a sharpened trapezoid, the structural parameters of the serrated boss include:

[0082] a length of the upper base and the lower base of the sharpened trapezoid;

[0083] a height of the sharpened trapezoid; and / or

[0084] a slope of the first oblique side and a slope of the second oblique side of the sharpened trapezoid,

[0085] when the shape of the cross section of the serrated boss is a rectangle, the structural parameters of the serrated boss include:

[0086] a height of the rectangle; and / or

[0087] a length of the rectangle.

[0088] Example 4. The antenna device of any of the above examples, wherein a relative position of the serrated boss to a horn aperture plane of the horn antenna and / or a size of the horn aperture plane is configured to change a radiation field of the antenna device, wherein the relative position of the serrated boss to the horn aperture plane includes:

[0089] a distance between a projection point of the first vertex of the triangle on the base and a first end point of the horn aperture plane;

[0090] a distance between a projection point of the center point of the upper base of the sharpened trapezoid on the lower base and the first end point of the horn aperture plane; or

[0091] a distance between the center point of the lower base of the rectangle and the first end point of the horn aperture plane.

[0092] Example 5. The antenna device of any of the above examples, wherein a corner of the base surface of the serrated boss that is not configured to be an edge chamfer has a chamfer radius that is no more than 30% of a minimum side length of a cross section of the serrated boss.

[0093] Example 6. The antenna device of any of the above examples, wherein the hollow channel is configured to include:

[0094] a rectangular opening in the longitudinal axis direction at a first end;

[0095] a closed wall at a second end, wherein the second end is opposite to the first end; and

[0096] a square wave shape that is bent back and forth around the longitudinal axis.

[0097] Example 7. The antenna device of any of the above examples, wherein the horn aperture plane of the horn antenna, the cross-section of the feed waveguide along a plane parallel to the horn aperture plane, and the shape of the slot of the meander waveguide are the same, including any of rectangular, elliptical, or circular.

[0098] Example 8. The antenna device of any of the above examples, wherein the hollow channel of the meander waveguide and the interior space of the horn antenna are filled with air to implement an array antenna of air waveguides, and the meander waveguide, the horn antenna, and the sawtooth-shaped protrusion comprise:

[0099] a metal material, or

[0100] a plastic material plated with a metal on a surface.

[0101] Example 9. The antenna device of any of the above examples, wherein the meander waveguide is formed by a plurality of identical square wave shapes connected in series along the longitudinal axis direction, and the spacing between adjacent square wave shapes in the longitudinal axis direction is less than one wavelength of the signal.

[0102] Example 10. The antenna device of any of the above examples, wherein the plurality of horn antennas are identical in shape, the number of horn antennas is equal to the number of complete square wave shapes, and the spacing between adjacent horn antennas is equal to the spacing between adjacent square wave shapes.

[0103] Example 11. A system comprising:

[0104] the antenna device of any of Examples 1-10; and

[0105] control circuitry configured to transmit or receive signals via the antenna device.

[0106] Example 12. The system of Example 11, wherein the system is configured for a vehicle.

Claims

1. An antenna device, comprising: A bent waveguide, wherein the bent waveguide bends back and forth around a longitudinal axis, the bent waveguide comprising: A curved hollow passageway; A first surface, the first surface defining the hollow channel; and One or more grooves passing through the first surface; One or more horn antennas, each of the one or more horn antennas comprising: A feed waveguide, wherein the hollow inner core of the feed waveguide is connected to the hollow channel of the bent waveguide through a slot in the first surface of the bent waveguide, such that at least a portion of the signal propagating in the hollow channel of the bent waveguide can enter the feed waveguide of the horn antenna through the slot; and An open-aperture radiator is configured as a hollow cavity with a horn shape. A first end of the hollow cavity is connected to the hollow core of the feed waveguide, and a second end of the hollow cavity is connected to the external environment, allowing signals from the feed waveguide to be transmitted through the open-aperture into the external environment. The horn shape has a slope. A sawtooth-shaped protrusion is positioned on both sides of the horn antenna and extends along the longitudinal axis. The cross-section of the sawtooth-shaped protrusion perpendicular to the longitudinal axis is sawtooth-shaped. The bottom edge of the sawtooth-shaped protrusion is coplanar with the horn aperture surface of the horn antenna. The structural parameters of the sawtooth-shaped protrusion, combined with the slope of the open radiator, are configured to enable the antenna device to generate a radiation field.

2. The antenna device as claimed in claim 1, wherein, The cross-sectional shape of the serrated boss includes one of a triangle, a tapered trapezoid, or a rectangle.

3. The antenna device as claimed in claim 2, wherein, When the cross-sectional shape of the sawtooth boss is triangular, the structural parameters of the sawtooth boss include: The perpendicular distance from the first vertex of the triangle to the bottom edge; The distance between the projection point of the first vertex of the triangle onto the base and the second vertex of the triangle; and / or The distance between the projection point of the first vertex of the triangle onto the base and the third vertex of the triangle. When the cross-sectional shape of the serrated boss is a tapered trapezoid, the structural parameters of the serrated boss include: The lengths of the upper and lower bases of the tapered trapezoid; The height of the sharpened trapezoid; and / or The inclination of the first hypotenuse and the inclination of the second hypotenuse of the pointed trapezoid. When the cross-sectional shape of the sawtooth boss is rectangular, the structural parameters of the sawtooth boss include: The height of the rectangle; and / or The length of the rectangle.

4. The antenna device as claimed in claim 2, wherein, The relative position of the sawtooth protrusion to the horn aperture surface of the horn antenna and / or the size of the horn aperture surface are configured to change the radiation field of the antenna device, wherein the relative position of the sawtooth protrusion to the horn aperture surface includes: The distance between the projection of the first vertex of the triangle onto the base and the first endpoint of the horn-shaped aperture surface; The distance between the projection of the center point of the upper base of the sharpened trapezoid onto the lower base and the first endpoint of the flared aperture surface; or The distance between the center point of the lower base of the rectangle and the first endpoint of the horn-shaped aperture surface.

5. The antenna device as claimed in claim 2, wherein, The corners of the serrated boss that are not on the bottom surface are configured with chamfered edges, and the radius of the chamfered edges does not exceed 30% of the minimum side length of the cross-section of the serrated boss.

6. The antenna device as described in any one of claims 1-5, wherein, The hollow channel is configured to include: A rectangular opening at the first end in the direction of the longitudinal axis; A closed wall at the second end, wherein the second end is opposite to the first end; and A square wave shape, wherein the square wave shape bends back and forth around the longitudinal axis.

7. The antenna device according to any one of claims 1-5, wherein, The horn aperture surface of the horn antenna, the cross-section of the feed waveguide along the surface parallel to the horn aperture surface, and the groove of the bent waveguide have the same shape, including any one of rectangular, elliptical, or circular shapes.

8. The antenna device according to any one of claims 1-5, wherein, The hollow channel of the bent waveguide and the internal space of the horn antenna are filled with air to realize an air waveguide array antenna, and the bent waveguide, the horn antenna, and the sawtooth protrusion include: Metal material, or Plastic material with a metal coating on the surface.

9. The antenna device as claimed in claim 6, wherein, The bent waveguide is formed by connecting multiple identical square wave shapes end to end along the longitudinal axis, and the distance between two adjacent square wave shapes in the longitudinal axis is less than one wavelength of the signal.

10. The antenna device as claimed in claim 9, wherein, The plurality of horn antennas are identical in shape, the number of horn antennas is equal to the number of complete square wave shapes, and the spacing between adjacent horn antennas is equal to the spacing between adjacent square wave shapes.

11. A system comprising: Antenna device as described in any one of claims 1-10; as well as A control circuit configured to transmit or receive signals via the antenna device.

12. The system of claim 11, wherein, The system is configured for use in vehicles.

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