Low-profile waveguide antenna array
By employing a cascaded power divider structure and connecting components in the waveguide antenna array, the spatial layout is optimized, solving the problem of large size of the waveguide antenna array and achieving improved low-profile broadband performance, making it suitable for applications such as automotive radar.
Patent Information
- Application Number
- CN202423204817.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-24
- Publication Date
- 2025-12-05
- Estimated Expiration
- 2034-12-24
AI Technical Summary
Existing waveguide antenna arrays are bulky due to the cascaded power dividers extending in multiple directions, making it difficult to meet the requirements for low profile.
A cascaded power divider structure is adopted. By setting the input ports of every two adjacent first power dividers to face opposite directions and using connecting components to connect the output ports in a zigzag manner, a cascaded power divider structure extending in the front and back is formed. Combined with parallel components and radiating components, the spatial layout is optimized.
It effectively reduces the height and volume of waveguide antenna arrays while improving performance, meeting the requirements for low profile broadband, and is suitable for fields such as automotive radar.
Smart Images
Figure CN223638622U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to antenna technical field, especially a kind of low profile waveguide antenna array. BACKGROUND
[0002] Waveguide antenna is widely applied in radar detection field due to its low loss, large power capacity, compact structure, easy processing and convenient separation characteristics, and low profile wideband waveguide antenna array is an important application requirement of automobile radar.
[0003] The waveguide array currently used is mainly realized by cascading multiple one-to-two power dividers, and the power divider cascade is usually extended in certain two directions to complete, so there is the problem of large volume.
[0004] Therefore, how to control the volume of waveguide antenna array belongs to the problem to be solved by the person skilled in the art. UTILITY MODEL CONTENT
[0005] The main purpose of the utility model is to provide a kind of low profile waveguide antenna array, to control the volume of waveguide antenna array.
[0006] To achieve the above purpose, the low profile waveguide antenna array provided by the utility model includes a cascaded power divider structure, the cascaded power divider structure includes a plurality of first power dividers arranged along the front-back direction, each first power divider is provided with an input port towards the left side or the right side and two output ports orthogonal to the input port, the input port is used to receive input signal, and the output port is used to output electromagnetic wave converted from input signal;Two first power dividers cooperating in front-back direction are first cooperating member and second cooperating member, the input port of the first cooperating member and the input port of the second cooperating member are in opposite direction, one output port in the first cooperating member and the input port in the second cooperating member are communicated by connecting assembly to transmit electromagnetic wave, and the other output port in the first cooperating member is connected with first radiating element to emit electromagnetic wave outward.
[0007] In an embodiment, the connecting assembly includes a first waveguide pipe and two first waveguide elbows;The first waveguide pipe extends along the front-back direction;Two first waveguide elbows are connected to the two ends of the first waveguide pipe respectively, and the two first waveguide elbows are connected with the output port of the first cooperating member and the input port of the second cooperating member.
[0008] In an embodiment, the first waveguide elbow has a first port and a second port, in the first port and the second port, one is used to connect the first waveguide pipe, and the other is used to connect the first cooperating member or the second cooperating member, and the electric field polarization of the input port and the output port of the first waveguide elbow is perpendicular to each other.
[0009] In an embodiment, the plurality of first power dividers, the plurality of connection assemblies, and the plurality of first radiating elements form a cascaded power divider structure, and a plurality of cascaded power divider structures are arranged in an array.
[0010] The low-profile waveguide antenna array further comprises a parallel assembly, the parallel assembly comprising a second power divider, a plurality of second waveguide bends, and a plurality of second waveguide tubes; the second power divider has one input port and a plurality of output ports, the input port of the second power divider is configured to receive an input signal, and the plurality of output ports of the second power divider are respectively connected to the input ports of the first mating pieces at the head ends of the plurality of cascaded power divider structures; the plurality of second waveguide tubes each extend along the front-back or up-down direction, and one end of each of the plurality of second waveguide tubes is connected to one of the plurality of output ports of the second power divider; the plurality of second waveguide bends each have one end connected to one of the plurality of second waveguide tubes, and the other end of each of the plurality of second waveguide bends is connected to the input port of the cascaded power divider structure.
[0011] In an embodiment, the low-profile waveguide antenna array comprises two cascaded power divider structures, the two cascaded power divider structures are arranged in front of and behind each other, the front end and the back end of the second power divider are respectively provided with output ports, the right end of the second power divider is provided with an input port, and the second waveguide tube extends along the front-back direction; the low-profile waveguide antenna array further comprises a radiating assembly, the radiating assembly comprises a third power divider provided with one right input port and a plurality of output ports, the input port of the third power divider is configured to receive an input signal, one of the plurality of output ports of the third power divider is arranged to the left to be connected to the input port of the second power divider; the radiating assembly further comprises one or more second radiating elements; one second radiating element is arranged between the two cascaded power divider structures, and the second radiating element is connected to the other output ports of the third power divider; a plurality of second radiating elements are arranged between the two cascaded power divider structures, the plurality of second radiating elements are respectively connected to the plurality of other output ports of the third power divider, and the plurality of second radiating elements are arranged in front of and behind each other.
[0012] In an embodiment, the two cascaded power divider structures are symmetrically arranged along the axis of the input port of the third power divider.
[0013] In an embodiment, the first radiating element is arranged as an open waveguide or a horn antenna, and / or the second radiating element is arranged as an open waveguide or a horn antenna.
[0014] In an embodiment, one of the output ports of the third power divider has the same polarization as the input port, and the remaining output ports have orthogonal polarization to the input port.
[0015] In one embodiment, the first radiating element and the first power divider are fixedly connected by a connector, the connector being provided with a floating pin that extends into the interior of the first radiating element; and / or, the second radiating element and the third power divider are fixedly connected by a connector, the connector being provided with a floating pin that extends into the second radiating element; and / or, the second power divider and the second waveguide are fixedly connected by a connector, the connector being provided with a floating pin that extends into the interior of the second waveguide.
[0016] In one embodiment, the output port of the second mating member at the end of the low-profile waveguide antenna array is connected to a third radiating element, which is configured as an open waveguide or a horn antenna.
[0017] The technical solution of this utility model sets the input ports of every two adjacent first power dividers to face opposite directions, and uses multiple connecting components to connect the output port of the first mating component to the input port of the second mating component in a zigzag manner. This allows multiple first power dividers to extend only in one direction, reducing the height and volume of the waveguide antenna array. Attached Figure Description
[0018] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.
[0019] Figure 1 A schematic diagram of a low-profile waveguide antenna array according to an embodiment of the present invention;
[0020] Figure 2 for Figure 1 Top view schematic diagram of the structure of a medium-low profile waveguide antenna array;
[0021] Figure 3 A top view of another embodiment of the present invention;
[0022] Figure 4 for Figure 1 H-plane radiation pattern of a medium-low profile waveguide antenna array;
[0023] Figure 5 for Figure 1 Antenna E-plane radiation pattern of a medium-low profile waveguide antenna array;
[0024] Figure 6 For Figure 1 Antenna standing wave pattern of the low profile waveguide antenna array.
[0025] Brief Description of the Drawings:
[0026] 100, low profile waveguide antenna array; 1, cascaded power divider structure; 11, first power divider; 12, connecting assembly; 121, first waveguide tube; 122, first waveguide elbow; 13, first radiating element; 14, third radiating element; 2, parallel assembly; 21, second power divider; 22, second waveguide tube; 23, second waveguide elbow; 3, radiating assembly; 31, third power divider; 32, second radiating element; 4, floating peg.
[0027] The purposes, functional features and advantages of the utility model will be further described with reference to the drawings in combination with embodiments. DETAILED DESCRIPTION
[0028] The technical solutions in the embodiments of the utility model will be clearly and completely described below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor belong to the protection scope of the utility model.
[0029] It should be noted that if the embodiments of the utility model involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement condition, etc. between components in a certain posture, and if the certain posture changes, the directional indications also change accordingly.
[0030] In addition, if the embodiments of the utility model involve descriptions such as "first", "second", etc., the descriptions of "first", "second", etc. are only for description purposes, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of indicated technical features. Therefore, the features limited by "first" and "second" can explicitly or implicitly include at least one of the features. In addition, "and / or" or "and / or" appearing throughout the text means that the three parallel schemes are included, taking "A and / or B" as an example, including A scheme, or B scheme, or A and B scheme. In addition, the technical solutions of each embodiment can be combined with each other, but it must be based on the realization of ordinary skilled in the art, when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, and is not within the protection scope required by the utility model.
[0031] The waveguide antenna is widely applied in the field of radar detection due to low loss, large power capacity, compact structure, easy processing and convenient separation, and the low-profile wideband waveguide antenna array is an important application requirement of the automobile radar. The waveguide array currently used is mainly realized by cascading multiple one-to-two power dividers, and the power divider cascade is usually extended in certain two directions to be completed, and thus there is a problem of large volume.
[0032] Based on this, the utility model provides a kind of low-profile waveguide antenna array. Please refer to Figures 1-3 In an embodiment of the utility model, the low-profile waveguide antenna array 100 includes cascaded power divider structure 1, the cascaded power divider structure 1 includes multiple first power dividers 11 spaced apart along front-back direction, each first power divider 11 is provided with an input port towards left side or right side and two output ports orthogonal to the input port, the input port is used to receive input signal, and the output port is used to output electromagnetic wave converted from input signal;Two first power dividers 11 mutually matched in front-back direction are first matching member and second matching member, the input port of the first matching member and the input port of the second matching member are opposite directions, one output port in the first matching member and the input port in the second matching member are communicated by connecting assembly 12 to transmit electromagnetic wave, and the other output port in the first matching member is connected with first radiating element 13 to emit electromagnetic wave outward.
[0033] The technical scheme of the utility model sets the input port of every two adjacent first power dividers 11 in opposite directions, uses multiple connecting assemblies 12 to connect the output port of the first matching member to the input port of the second matching member in zigzag, so that multiple first power dividers 11 can only extend along one direction of front-back direction, and the height and volume of the waveguide antenna array are reduced.
[0034] Among them, the first power divider 11 is a passive device that equally or unequally divides one input signal into two output signals, has one input port and two output ports, and is a one-to-two power divider.
[0035] In an embodiment of the utility model, the connecting assembly 12 includes first waveguide pipe 121 and two first waveguide elbows 122;First waveguide pipe 121 extends along front-back direction;Two first waveguide elbows 122 are connected to two ends of the first waveguide pipe 121 respectively, and the two first waveguide elbows 122 are connected with the output port of the first matching member and the input port of the second matching member. In this way, the first matching member and the second matching member are connected by first waveguide pipe 121 and two first waveguide elbows 122, and the phase is controlled by controlling the length and width of first waveguide pipe 121 and first waveguide elbow 122, and the zigzag arrangement of first waveguide elbow 122 can provide sufficient space for phase control.
[0036] In an embodiment of the utility model, first waveguide elbow 122 has first port and second port, in first port and second port, one is used to connect first waveguide pipe, the other is used to connect first fitting or second fitting, the input port and the output port of first waveguide elbow 122 electric field polarization is perpendicular to each other. So set up, reduce the bending loss by using E-H 90 ° bend waveguide, carry out mode conversion, and facilitate space layout.
[0037] In an embodiment of the utility model, the multiple first power dividers 11, the multiple connection components 12, the multiple first radiation elements 13 form a cascaded power divider structure 1, the cascaded power divider structure 1 is provided with multiple, the multiple cascaded power divider structures 1 are arrayed;The low-profile waveguide antenna array 100 further includes a parallel component 2, the parallel component 2 includes a second power divider 21, multiple second waveguide elbows 23 and multiple second waveguide elbows 23;Second power divider 21 has an input port and multiple output ports, the input port of second power divider 21 is used to receive input signal, the multiple output ports of second power divider 21 are connected with the input port of the first fitting of the head end of multiple cascaded power divider structures 1 respectively;Multiple second waveguide tubes 22 each second waveguide tube 22 extends along front and back or up and down, and one end of multiple second waveguide tubes 22 is connected with multiple output ports of second power divider 21 respectively;Multiple second waveguide elbows 23, each second waveguide elbow 23 one end is connected with second waveguide tube 22 the other end, and the other end of multiple waveguide elbows is connected with the input port of cascaded power divider structure 1. Multiple cascaded power divider structures 1 are arranged in this way to significantly improve the performance of low-profile waveguide antenna array 100, and parallel feeding structure, the machining precision requirement is low.
[0038] In an embodiment in which the multiple cascaded power divider structures 1 are arrayed, two cascaded power divider structures 1 are arranged along the up and down direction, the second power divider 21 has two output ports, and the two second waveguide tubes 22 extend along the up and down direction to form a two-row multi-column array. In another embodiment, two cascaded power divider structures 1 are arranged along the front and back direction, the second power divider 21 has two output ports, and the two second waveguide tubes 22 extend along the front and back direction to form a one-row multi-column array.
[0039] In an embodiment of the utility model, the low profile waveguide antenna array 100 includes two cascade power divider structures 1, the two cascade power divider structures 1 are arranged along front-back interval, the forward end and the backward end of the second power divider 21 are respectively provided with output port, the right end of the second power divider 21 is provided with input port, the second waveguide tube 22 extends along front-back direction;The low profile waveguide antenna array 100 further includes radiating assembly 3, the radiating assembly 3 includes third power divider 31, is provided with one right input port and multiple output ports, the input port of the third power divider 31 is used to receive input signal, one of the multiple output ports of the third power divider 31 is arranged to the left to be connected with the input port of the second power divider 21;Radiating assembly 3 further includes one or more second radiating elements 32;One second radiating element 32 is arranged between the two cascade power divider structures 1, and the second radiating element 32 is connected with the other output ports of the third power divider 31;Multiple second radiating elements 32 are arranged between the two cascade power divider structures 1, and the multiple second radiating elements 32 are respectively connected with the multiple other output ports of the third power divider 31, and the multiple second radiating elements 32 are arranged along front-back interval. In this way, before the signal enters the second power divider 21, electromagnetic waves are emitted by the multiple second radiating elements 32 to improve the performance of the low profile waveguide antenna array 100.
[0040] In an embodiment, the low profile waveguide antenna array 100 is an even array as shown in Figure 2 The third power divider 31 is a three-way power divider connected with two second radiating elements 32. Figure 3 In another embodiment, the low profile waveguide antenna array 100 is an odd array as shown in The third power divider 31 is a two-way power divider connected with one second radiating element 32.
[0041] Further, the input port of the third power divider 31 is connected with an external receiver feeder.
[0042] In an embodiment of the utility model, the two cascade power divider structures 1 are arranged symmetrically along the axis of the input port of the third power divider 31. In this way, it is beneficial to the design of the symmetric pattern.
[0043] In an embodiment of the utility model, the first radiating element 13 is arranged as an open waveguide or a horn antenna.
[0044] In an embodiment of the utility model, the second radiating element 32 is arranged as an open waveguide or a horn antenna. In this way, the use of open waveguide or horn antenna increases the bandwidth of the low profile waveguide antenna array 100.
[0045] In an embodiment of the utility model, one output port of third power divider 31 is same with input port polarization, the rest output port is orthogonal with input port polarization, so as to facilitate subsequent phase control, make subsequent each port phase amplitude meet the requirement and polarization is consistent.
[0046] In an embodiment of the utility model, first radiating element 13 and first power divider 11 are fixedly connected through connecting piece, first floating pin 4 is arranged on connecting piece, and first floating pin 4 is deep into first radiating element 13 inside, so that the equal or unequal power division and impedance matching of two output ports of first power divider 11 can be realized by adjusting the position and height of first floating pin 4.
[0047] In an embodiment of the utility model, second power divider 21 and second waveguide 22 are fixedly connected through connecting piece, second floating pin 4 is arranged on connecting piece, and second floating pin 4 is deep into second waveguide 22 inside, so that the equal or unequal power division and impedance matching of multiple output ports of second power divider 21 can be realized by adjusting the position and height of second floating pin 4.
[0048] In an embodiment of the utility model, second radiating element 32 and third power divider 31 are fixedly connected through connecting piece, third floating pin 4 is arranged on connecting piece, and third floating pin 4 is deep into second radiating element 32, so that the equal or unequal power division and impedance matching of multiple output ports of third power divider 31 can be realized by adjusting the position and height of floating third pin.
[0049] Wherein, each floating pin 4 can be cylinder, cuboid, ladder or other solid structure.
[0050] In an embodiment of the utility model, the output port of the second matching piece at the end of the low-profile waveguide antenna array 100 is connected with the third radiating element 14, and the third radiating element 14 is arranged as an open waveguide or a horn antenna to increase the wide bandwidth of the low-profile waveguide antenna array 100.
[0051] On the basis of the above embodiment, by adjusting the position and height of each radiating element and each floating pin 4, array side lobe weighting can be realized, by adjusting the length and width of each waveguide, array beam pointing deflection can be realized, and by jointly adjusting each radiating element, each floating pin 4 and each waveguide, beam shaping can be realized. Wherein, the radiating element includes first radiating element 13, second radiating element 32 and third radiating element 14, the floating pin 4 includes first floating pin 4, second floating pin 4 and third floating pin 4, and each waveguide includes first waveguide 121 and second waveguide 22.
[0052] Based on the above embodiment, the calculation method of the long side length (the size along the front-to-back direction) a of the first waveguide and the second waveguide is as follows:
[0053] The interval along the front-to-back direction of two adjacent radiation elements is d (the interval between the cavities in the two radiation elements), the width of the radiation element along the left-to-right direction is b, the interval along the left-to-right direction of the first waveguide and the second waveguide is d0, and the inter-element signal path length L of the low-profile waveguide antenna array can be obtained:
[0054] If the low-profile waveguide antenna array is an even array, the output end signal path length of the second power divider is L=1.5xd+0.5xd0; the signal path length of other adjacent elements is L=d+d0-b; if the low-profile waveguide antenna array is an odd array, the signal path length of adjacent elements is L=d+d0-b.
[0055] Further, the following can be obtained:
[0056]
[0057] Where λ0 is the center frequency of the waveguide antenna array; the above-mentioned feeding structure is completed within the waveguide H plane height, and is usually not more than 1 wavelength.
[0058] In an embodiment of the utility model, provide a kind of low-profile waveguide antenna array, working frequency band 76GHz-81GHz, beam pointing normal.
[0059] The long side of the external receiving and transmitting machine feeder is 2.5mm, the narrow side is 0.85mm, d=3.5mm, b=0.85mm, d0=3.7mm, and the following can be obtained:
[0060] The long side a1 of the first waveguide is 2.57mm; the long side length a2 of the second waveguide is 2.42mm.
[0061] As Figure 4 And Figure 5 It is antenna pattern, and different frequency direction Figure 1 Good consistency, and beam pointing deviation is less than 1 °; as Figure 6 It is antenna standing wave pattern, and 76GHz-81GHz is less than 2.
[0062] In another embodiment of the utility model, provide a kind of low-profile waveguide antenna array, working frequency band 76GHz-81GHz, beam pointing normal.
[0063] The long side of the external receiving and transmitting machine feeder is 2.5mm, the narrow side is 0.85mm, d=3.5mm, b=0.85mm, d0=3.7mm, and the following can be obtained:
[0064] The long side a3 of the first waveguide is 2.57 mm, and the long side length a4 of the second waveguide is 2.57 mm.
[0065] The above merely illustrates the exemplary embodiments of the present application, and does not limit the patent scope of the present application, and any equivalent structural transformation or direct / indirect application in other related technical fields under the technical concept of the present application and by using the content of the present application specification and drawings is included in the patent protection scope of the present application.
Claims
1. A low profile waveguide antenna array, characterized by, The low-profile waveguide antenna array comprises a plurality of cascaded power divider structures, each of the cascaded power divider structures comprising a plurality of first power dividers arranged in a front-rear direction, each of the first power dividers being provided with an input port facing left or right and two output ports orthogonal to the input port, the input port being configured to receive an input signal, and the output ports being configured to output electromagnetic waves converted from the input signal. The two first power dividers arranged in the front-rear direction are a first cooperating member and a second cooperating member, the input port of the first cooperating member facing in an opposite direction to the input port of the second cooperating member, one of the output ports of the first cooperating member being in communication with the input port of the second cooperating member through a connecting assembly to transmit electromagnetic waves, and the other output port of the first cooperating member being connected with a first radiating element to emit electromagnetic waves outward.
2. The low profile waveguide antenna array of claim 1, wherein, The connecting assembly comprises: a first waveguide tube extending in the front-rear direction; and two first waveguide bends connected to two ends of the first waveguide tube respectively, the two first waveguide bends being connected with the output port of the first cooperating member and the input port of the second cooperating member.
3. The low profile waveguide antenna array of claim 2, wherein, The first waveguide bend has a first port and a second port, one of the first port and the second port being configured to connect the first waveguide tube, and the other being configured to connect the first cooperating member or the second cooperating member, the input port and the output port of the first waveguide bend being perpendicular to each other in terms of electric field polarization.
4. The low profile waveguide antenna array of claim 1, wherein, The low-profile waveguide antenna array comprises a plurality of cascaded power divider structures, each of the cascaded power divider structures comprising a plurality of first power dividers arranged in a front-rear direction, each of the first power dividers being provided with an input port facing left or right and two output ports orthogonal to the input port, the input port being configured to receive an input signal, and the output ports being configured to output electromagnetic waves converted from the input signal. The low-profile waveguide antenna array further comprises a parallel assembly, the parallel assembly comprising: a second power divider having an input port and a plurality of output ports, the input port of the second power divider being configured to receive an input signal, and the plurality of output ports of the second power divider being connected with the input ports of the first cooperating members of the head ends of the plurality of cascaded power divider structures respectively; a plurality of second waveguide tubes, each of the second waveguide tubes extending in the front-rear or up-down direction, and one end of each of the plurality of second waveguide tubes being connected with the plurality of output ports of the second power divider respectively; and a plurality of second waveguide bends, one end of each of the second waveguide bends being connected with the other end of the second waveguide tube, and the other end of each of the plurality of waveguide bends being connected with the input port of the cascaded power divider structure.
5. The low profile waveguide antenna array of claim 4, wherein, The low-profile waveguide antenna array comprises two cascaded power divider structures arranged in the front-rear direction, the front end and the rear end of the second power divider being provided with output ports respectively, and the right end of the second power divider being provided with an input port, the second waveguide tube extending in the front-rear direction. The low-profile waveguide antenna array further comprises a radiating assembly, the radiating assembly comprising a third power divider provided with an input port facing right and a plurality of output ports, the input port of the third power divider being configured to receive an input signal, and one of the plurality of output ports of the third power divider facing left to be connected with the input port of the second power divider, the radiating assembly further comprising: a second radiating element arranged between the two cascaded power divider structures, the second radiating element being connected with the other output ports of the third power divider; or a third radiating element arranged between the two cascaded power divider structures, the third radiating element being connected with the other output ports of the third power divider. A plurality of second radiating elements are arranged between the two cascaded power divider structures, and the plurality of second radiating elements are respectively connected with a plurality of other output ports of the third power divider and are arranged along the front-back direction.
6. The low profile waveguide antenna array of claim 5, wherein, The two cascaded power divider structures are symmetrically arranged along the axis of the third power divider input port.
7. The low profile waveguide antenna array of claim 5, wherein, The first radiating element is arranged as an open waveguide or a horn antenna, and / or, The second radiating element is arranged as an open waveguide or a horn antenna.
8. The low profile waveguide antenna array of claim 5, wherein, One output port of the third power divider is the same as the polarization of the input port, and the rest of the output ports are orthogonal to the polarization of the input port.
9. A low profile waveguide antenna array as claimed in any one of claims 5 to 8, characterized in that, The first radiating element is fixedly connected with the first power divider through a connecting piece, and a floating pin is arranged on the connecting piece and deeply penetrates into the first radiating element; and / or, The second radiating element is fixedly connected with the third power divider through a connecting piece, and a floating pin is arranged on the connecting piece and deeply penetrates into the second radiating element; and / or, The second power divider is fixedly connected with the second waveguide through a connecting piece, and a floating pin is arranged on the connecting piece and deeply penetrates into the second waveguide.
10. The low-profile waveguide antenna array of any one of claims 1 to 8, wherein, The output port of the second matching piece at the end of the low-profile waveguide antenna array is connected with a third radiating element, and the third radiating element is arranged as an open waveguide or a horn antenna.