A waveguide antenna array based on unequal feed network

Abstract

The present invention discloses a waveguide antenna array based on an unequally divided feeding network, comprising a first power divider, a first feeder, a second feeder, a first radiation port group and a second radiation port group, wherein one end of the first feeder is connected to an output end of the first power divider, one end of the second feeder is connected to another output end of the first power divider, the first radiation port group is connected to the other end of the first feeder, the second radiation port group is connected to the other end of the second feeder, the first radiation port group comprises at least one radiation port, the second radiation port group comprises an even number of radiation ports, and the even number of radiation ports are equally divided into two groups and symmetrically arranged on both sides of the first radiation port group, and the number of radiation ports of the first radiation port group is less than the number of radiation ports of the second radiation port group. The present invention realizes flexible adjustment of the directional pattern of the pitch plane, flexible adjustment of the radiation port amplitude ratio, and low cost with few antenna layers.

Description

Technical Field

[0001] The invention relates to a waveguide antenna array, in particular to a waveguide antenna array based on an unequally divided feeding network, and belongs to the technical field of antennas. Background Art

[0002] The waveguide feeding network is an important component of the waveguide planar array antenna, and its key indicators are amplitude distribution and phase distribution. The traditional waveguide feeding network usually adopts a rectangular waveguide HT power divider network structure, which is composed of a group of rectangular waveguide H-plane T-type power dividers (HT power dividers for short) cascaded.

[0003] For example, Chinese patent publication number CN118825610A discloses a waveguide array antenna, which belongs to the field of waveguide antenna technology, and includes two layers of metal plates, a waveguide bending structure of a waveguide antenna unit, a waveguide power divider and a waveguide transmission line. A receiving cavity is provided in the two layers of metal plates, one end of the waveguide bending structure is connected to the waveguide transmission line, and the other end extends in a horizontal direction, and the other end of the waveguide bending structure has an upward bending portion, the waveguide power divider is located at the upper end of the bending portion, the waveguide antenna unit is located at the upper end of the waveguide power divider, the waveguide bending structure is located in the receiving cavity of the lower metal plate, the waveguide antenna unit is located in the receiving cavity of the upper metal plate, and the upper and lower parts of the waveguide power divider are respectively located in the receiving cavities of the two layers of metal plates; the waveguide array antenna provided by the present invention has a 35% smaller size in the vertical direction than a waveguide array antenna form without introducing a waveguide bending structure, and only two layers of metal plates are required.

[0004] The power divider of the waveguide antenna in this scheme is a one-to-four equal power divider, that is, the amplitude obtained by each unit is equal, and the gain and sidelobe adjustment optimization of the antenna pitch plane are relatively limited.

[0005] For another example, Chinese patent publication number CN115189122A discloses a non-metallic waveguide array antenna and a manufacturing method thereof, wherein the non-metallic waveguide array antenna includes a cavity antenna board and an antenna emitting board stacked on the cavity antenna board; the antenna emitting board and the cavity antenna board are both integrally formed with a low-warping high-performance engineering plastic, and the surfaces are both provided with a metal coating; a radiation array formed by rectangular gaps is provided on the antenna emitting board, and a waveguide transmission cavity structure is provided on the cavity antenna board. This application uses high-performance engineering plastics to replace metal substrates, obtains plastic workpieces with high dimensional accuracy through mold design and processing control, and then uses plastic surface metallization to prepare waveguide array antenna components with the help of reflow soldering / ultrasonic processes. Compared with existing metal waveguide array antennas, this application has the advantages of lightweight, low cost, and mass production while ensuring high gain requirements.

[0006] This solution requires four layers of waveguide plates, which increases the number of welding and installation times, resulting in a decrease in yield and an increase in cost. The power divider feed network of this solution is divided into four equal power dividers, and there is also a problem that the gain and sidelobe adjustment optimization of the antenna pitch plane are relatively limited.

[0007] It can be seen that the existing waveguide antenna array has the following defects:

[0008] 1. The conventional cavity waveguide antenna power divider is one-to-two, one-to-four or one-to-eight, and the antenna H-plane radiation pattern design is not flexible enough;

[0009] 2. The amplitude ratios of each port of the conventional cavity waveguide antenna power divider are equal. If the antenna needs to reduce the side lobe, for example, the amplitude ratio of the antenna aperture field needs to be Chebyshev or Taylor distribution, the size of the waveguide port is generally used to control it. Considering the processing size limitation, the amplitude ratio of each port can be adjusted to a limited extent;

[0010] 3. Conventional cavity feeding solutions use three-layer or four-layer waveguide antennas, which are costly. Summary of the invention

[0011] The technical problem to be solved by the present invention is to provide a waveguide antenna array based on an unequally divided feeding network, so as to realize flexible adjustment of the directional pattern of the elevation plane and the amplitude ratio of the radiation port.

[0012] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0013] A waveguide antenna array based on an unequal feeding network comprises a first power divider, a first feeder, a second feeder, a first radiation port group and a second radiation port group, wherein one end of the first feeder is connected to an output end of the first power divider, one end of the second feeder is connected to another output end of the first power divider, the first radiation port group is connected to the other end of the first feeder, and the second radiation port group is connected to the other end of the second feeder, the first radiation port group comprises at least one radiation port, the second radiation port group comprises an even number of radiation ports, and the even number of radiation ports are equally divided into two groups and symmetrically arranged on both sides of the first radiation port group, and the number of radiation ports in the first radiation port group is less than the number of radiation ports in the second radiation port group.

[0014] Further, the length difference between the first feeder and the second feeder is X so that the phase difference between the first feeder signal at the output end of the first feeder and the second feeder signal at the output end of the second feeder is 0.

[0015] Furthermore, the radiation ports in the first radiation port group and the second radiation port group are distributed in a Taylor synthesis array.

[0016] Furthermore, the input end of the first power divider is connected to the feeding port through a first impedance matching.

[0017] Furthermore, the first radiation port group includes a second impedance matching and a first radiation port, and the other end of the first feeder is connected to the first radiation port through the second impedance matching.

[0018] Furthermore, the first radiation port group includes a second impedance matching, a second power divider and two first radiation ports, the other end of the first feeder is connected to the input end of the second power divider through the second impedance matching, one output end of the second power divider is connected to a first radiation port, and the other output end of the second power divider is connected to another first radiation port.

[0019] Furthermore, the second radiation port includes a third impedance matching, a third power divider and two second radiation ports, the other end of the second feeder is connected to the input end of the third power divider through the third impedance matching, one output end of the third power divider is connected to a second radiation port, and the other output end of the third power divider is connected to another second radiation port.

[0020] Furthermore, the second radiation port includes a third impedance matching, a third power divider, a fourth impedance matching, a fourth power divider, a fifth impedance matching, a fifth power divider and four second radiation ports, the four second radiation ports being, from left to right, a second radiation port one, a second radiation port two, a second radiation port three and a second radiation port four, the other end of the second feeder is connected to the input end of the third power divider through the third impedance matching, an output end of the third power divider is connected to the input end of the fourth power divider through the fourth impedance matching, an output end of the fourth power divider is connected to the second radiation port one, another output end of the fourth power divider is connected to the second radiation port two, another output end of the third power divider is connected to the input end of the fifth power divider through the fifth impedance matching, an output end of the fifth power divider is connected to the second radiation port three, and another output end of the fifth power divider is connected to the second radiation port four.

[0021] Furthermore, the length of the second radiation port and the second radiation port is 2.8 mm, the width of the second radiation port and the second radiation port is 0.9 mm, the length of the second radiation port and the second radiation port is 2.8 mm, the width of the second radiation port and the second radiation port is 1.6 mm, the length of the first radiation port is 2.8 mm, the width of the first radiation port is 1.8 mm, and the amplitude ratio of the second radiation port, the second radiation port, the first radiation port, the second radiation port and the second radiation port is 0.09:0.13:0.5625:0.13:0.09.

[0022] Furthermore, the center distance between the first radiation port and the second radiation port two or the second radiation port three is 3.3 mm, the center distance between the second radiation port one and the second radiation port two, and the center distance between the second radiation port three and the second radiation port four is 3.8 mm.

[0023] Compared with the prior art, the present invention has the following advantages and effects:

[0024] 1. The present invention adopts a one-to-three, one-to-five or one-to-six feeding network, which can flexibly design the H-plane radiation pattern of the antenna;

[0025] 2. The present invention adopts an unequally divided feeding network to feed the antenna, which can realize the distribution of the antenna aperture field amplitude naturally showing a high middle and low edge distribution. For example, the amplitude ratio of the one-to-three feeding network is: 0.25:0.5:0.25; the amplitude ratio of the one-to-five feeding network is: 0.125:0.125:0.5:0.125:0.125; the amplitude ratio of the one-to-six feeding network is: 0.125:0.125:0.25:0.25:0.125:0.125; and the amplitude ratio can be adjusted in accordance with the waveguide port size, which is more flexible.

[0026] 3. The unequally divided feeding network of the present invention is simple in design and only requires two layers, thus reducing material costs and improving yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of Embodiment 1 of a waveguide antenna array based on an unequally divided feeding network of the present invention.

[0028] Figure 2 It is a schematic diagram of Embodiment 2 of a waveguide antenna array based on an unequally divided feeding network of the present invention.

[0029] Figure 3 It is a schematic diagram of Embodiment 3 of a waveguide antenna array based on an unequally divided feeding network of the present invention.

[0030] Figure 4 The invention discloses a central frequency point E-plane and H-plane directional diagram of a waveguide antenna array based on an unequally divided feeding network.

[0031] Figure 5 It is a performance curve diagram of a waveguide antenna array based on an unequally divided feeding network in the bandwidth of 74-82GHz of the present invention. DETAILED DESCRIPTION

[0032] In order to elaborate on the technical scheme adopted by the present invention to achieve the predetermined technical purpose, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only partial embodiments of the present invention, rather than all embodiments, and the technical means or technical features in the embodiments of the present invention can be replaced without paying creative work. The present invention will be described in detail below with reference to the drawings and in conjunction with the embodiments.

[0033] Example 1: Figure 1As shown, a waveguide antenna array based on an unequal feeding network of the present invention comprises a first power divider 1, a first feeder 2, a second feeder 3, a first radiation port group and a second radiation port group, one end of the first feeder 2 is connected to an output end of the first power divider 1, one end of the second feeder 3 is connected to the other output end of the first power divider 1, the first radiation port group is connected to the other end of the first feeder 2, the second radiation port group is connected to the other end of the second feeder 3, the first radiation port group comprises at least one radiation port, the second radiation port group comprises an even number of radiation ports and the even number of radiation ports are equally divided into two groups and symmetrically arranged on both sides of the first radiation port group, and the number of radiation ports in the first radiation port group is less than the number of radiation ports in the second radiation port group.

[0034] The length difference between the first feeder line 2 and the second feeder line 3 is X so that the phase difference between the first feeder line signal at the output end of the first feeder line 2 and the second feeder line signal at the output end of the second feeder line 3 is 0.

[0035] The radiation ports in the first radiation port group and the second radiation port group are distributed in a Taylor comprehensive array.

[0036] The input end of the first power divider 1 is connected to the feeding port 5 through the first impedance matching 4 .

[0037] The first radiation port group includes a second impedance matcher 6 and a first radiation port 7 , and the other end of the first feeder line 2 is connected to the first radiation port 7 through the second impedance matcher 6 .

[0038] The second radiation port includes a third impedance matching 8, a third power divider 9, a fourth impedance matching 10, a fourth power divider 11, a fifth impedance matching 12, a fifth power divider 13 and four second radiation ports, the four second radiation ports being respectively a second radiation port 14, a second radiation port 2 15, a second radiation port 3 16 and a second radiation port 4 17 from left to right, the other end of the second feeder 3 is connected to the input end of the third power divider 9 through the third impedance matching 8, an output end of the third power divider 9 is connected to the input end of the fourth power divider 11 through the fourth impedance matching 10, an output end of the fourth power divider 11 is connected to the second radiation port 14, another output end of the fourth power divider 11 is connected to the second radiation port 2 15, another output end of the third power divider 9 is connected to the input end of the fifth power divider 13 through the fifth impedance matching 12, an output end of the fifth power divider 13 is connected to the second radiation port 3 16, and another output end of the fifth power divider 13 is connected to the second radiation port 4 17.

[0039] The length of the second radiation port 14 and the second radiation four ports 17 is 2.8 mm, the width of the second radiation port 14 and the second radiation four ports 17 is 0.9 mm, the length of the second radiation two ports 15 and the second radiation three ports 16 is 2.8 mm, the width of the second radiation two ports 15 and the second radiation three ports 16 is 1.6 mm, the length of the first radiation port 7 is 2.8 mm, the width of the first radiation port 7 is 1.8 mm, and the amplitude ratio of the second radiation port 14, the second radiation two ports 15, the first radiation port 7, the second radiation three ports 16 and the second radiation four ports 17 is 0.09:0.13:0.5625:0.13:0.09. According to Taylor synthesis, the current amplitude reaches a maximum value at the middle gap and gradually decreases. Within a certain range, the larger the width of the radiation port, the more coupling energy. However, considering the processing, the size of the radiation port cannot be infinitely reduced. Therefore, the initial energy distribution of the radiation port is more important. The initial radiation port amplitude ratio of the present invention is 0.125:0.125:0.5:0.125:0.125. After adjusting the size of the radiation port, the amplitude ratio can be 0.09:0.13:0.5625:0.13:0.09. At the same time, the radiation port spacing is optimized to achieve a sidelobe effect of -27dB.

[0040] The center distance between the first radiation port 7 and the second radiation port 2 15 or the second radiation port 3 16 is 3.3 mm, the center distance between the second radiation port 14 and the second radiation port 2 15 and the center distance between the second radiation port 3 16 and the second radiation port 4 17 is 3.8 mm.

[0041] Example 2: Figure 2 As shown, a waveguide antenna array based on an unequal feeding network of the present invention comprises a first power divider 1, a first feeder 2, a second feeder 3, a first radiation port group and a second radiation port group, one end of the first feeder 2 is connected to an output end of the first power divider 1, one end of the second feeder 3 is connected to the other output end of the first power divider 1, the first radiation port group is connected to the other end of the first feeder 2, the second radiation port group is connected to the other end of the second feeder 3, the first radiation port group comprises at least one radiation port, the second radiation port group comprises an even number of radiation ports and the even number of radiation ports are equally divided into two groups and symmetrically arranged on both sides of the first radiation port group, and the number of radiation ports in the first radiation port group is less than the number of radiation ports in the second radiation port group.

[0042] The length difference between the first feeder line 2 and the second feeder line 3 is X so that the phase difference between the first feeder line signal at the output end of the first feeder line 2 and the second feeder line signal at the output end of the second feeder line 3 is 0.

[0043] The radiation ports in the first radiation port group and the second radiation port group are distributed in a Taylor comprehensive array.

[0044] The input end of the first power divider 1 is connected to the feeding port 5 through the first impedance matching 4 .

[0045] The first radiation port group includes a second impedance matcher 6 and a first radiation port 7 , and the other end of the first feeder line 2 is connected to the first radiation port 7 through the second impedance matcher 6 .

[0046] The second radiation port includes a third impedance match 8, a third power divider 9 and two second radiation ports. The other end of the second feeder line 3 is connected to the input end of the third power divider 9 through the third impedance match 8, an output end of the third power divider 9 is connected to a second radiation port through a fourth impedance match 10, and the other output end of the third power divider 9 is connected to another second radiation port through a fifth impedance match 12.

[0047] Example 3: Figure 3 As shown, a waveguide antenna array based on an unequal feeding network of the present invention comprises a first power divider 1, a first feeder 2, a second feeder 3, a first radiation port group and a second radiation port group, one end of the first feeder 2 is connected to an output end of the first power divider 1, one end of the second feeder 3 is connected to the other output end of the first power divider 1, the first radiation port group is connected to the other end of the first feeder 2, the second radiation port group is connected to the other end of the second feeder 3, the first radiation port group comprises at least one radiation port, the second radiation port group comprises an even number of radiation ports and the even number of radiation ports are equally divided into two groups and symmetrically arranged on both sides of the first radiation port group, and the number of radiation ports in the first radiation port group is less than the number of radiation ports in the second radiation port group.

[0048] The length difference between the first feeder line 2 and the second feeder line 3 is X, so that the phase difference between the first feeder line signal in the first feeder line 2 and the second feeder line signal in the second feeder line 3 is 0.

[0049] The radiation ports in the first radiation port group and the second radiation port group are distributed in a Taylor comprehensive array.

[0050] The input end of the first power divider 1 is connected to the feeding port 5 through the first impedance matching 4 .

[0051] The first radiation port group includes a second impedance matcher 6, a second power divider 18 and two first radiation ports 7. The other end of the first feeder line 2 is connected to the input end of the second power divider 18 through the second impedance matcher 6, one output end of the second power divider 18 is connected to one first radiation port 7, and the other output end of the second power divider 18 is connected to another first radiation port 7.

[0052] The second radiation port includes a third impedance matching 8, a third power divider 9, a fourth impedance matching 10, a fourth power divider 11, a fifth impedance matching 12, a fifth power divider 13 and four second radiation ports, the four second radiation ports being respectively a second radiation port 14, a second radiation port 2 15, a second radiation port 3 16 and a second radiation port 4 17 from left to right, the other end of the second feeder 3 is connected to the input end of the third power divider 9 through the third impedance matching 8, an output end of the third power divider 9 is connected to the input end of the fourth power divider 11 through the fourth impedance matching 10, an output end of the fourth power divider 11 is connected to the second radiation port 14, another output end of the fourth power divider 11 is connected to the second radiation port 2 15, another output end of the third power divider 9 is connected to the input end of the fifth power divider 13 through the fifth impedance matching 12, an output end of the fifth power divider 13 is connected to the second radiation port 3 16, and another output end of the fifth power divider 13 is connected to the second radiation port 4 17.

[0053] Taking Example 1 as an example, Figure 4 The figure shows the E-plane and H-plane radiation patterns at the center frequency. It can be seen that the five-element antenna array of Example 1 can achieve a side lobe of -27dB. Figure 5 The figure shows the performance curve of the antenna of Example 1 of the present invention within the bandwidth of 74-82 GHz. It can be seen that the present invention has a wider antenna working bandwidth and the antenna has better performance within the bandwidth of 74-82 GHz.

[0054] The present invention can realize the array of antenna units with even radiation ports, and can also realize the array of antenna units with odd radiation ports, and can flexibly adjust the directional pattern of the elevation plane by coordinating the amplitude ratio of the feeding network. The antenna of the present invention only needs two layers to be realized, which reduces the cost.

[0055] The above is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technician familiar with this profession can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent replacement and improvement made to the above embodiments without departing from the content of the technical solution of the present invention, based on the technical essence of the present invention, within the spirit and principles of the present invention, still fall within the protection scope of the technical solution of the present invention.

Claims

1. A waveguide antenna array based on an unequally divided feeding network, characterized in that: It includes a first power divider, a first feeder, a second feeder, a first radiation port group and a second radiation port group, one end of the first feeder is connected to an output end of the first power divider, one end of the second feeder is connected to the other output end of the first power divider, the first radiation port group is connected to the other end of the first feeder, the second radiation port group is connected to the other end of the second feeder, the first radiation port group includes at least one radiation port, the second radiation port group includes an even number of radiation ports and the even number of radiation ports are equally divided into two groups and symmetrically arranged on both sides of the first radiation port group, and the number of radiation ports in the first radiation port group is less than the number of radiation ports in the second radiation port group.

2. A waveguide antenna array based on an unequally divided feeding network according to claim 1, characterized in that: The length difference between the first feeder and the second feeder is X so that the phase difference between the first feeder signal at the output end of the first feeder and the second feeder signal at the output end of the second feeder is 0.

3. The waveguide antenna array based on an unequally divided feeding network according to claim 1, characterized in that: The radiation ports in the first radiation port group and the second radiation port group are distributed in a Taylor synthesis array.

4. The waveguide antenna array based on an unequally divided feeding network according to claim 1, characterized in that: The input end of the first power divider is connected to the feeding port through a first impedance matching.

5. The waveguide antenna array based on an unequally divided feeding network according to claim 1, characterized in that: The first radiation port group includes a second impedance matching and a first radiation port, and the other end of the first feeder is connected to the first radiation port through the second impedance matching.

6. The waveguide antenna array based on an unequally divided feeding network according to claim 1, characterized in that: The first radiation port group includes a second impedance matching, a second power divider and two first radiation ports. The other end of the first feeder is connected to the input end of the second power divider through the second impedance matching, one output end of the second power divider is connected to a first radiation port, and the other output end of the second power divider is connected to another first radiation port.

7. The waveguide antenna array based on an unequally divided feeding network according to claim 5, characterized in that: The second radiation port includes a third impedance matching, a third power divider and two second radiation ports. The other end of the second feeder is connected to the input end of the third power divider through the third impedance matching, an output end of the third power divider is connected to a second radiation port, and the other output end of the third power divider is connected to another second radiation port.

8. A waveguide antenna array based on an unequally divided feeding network according to claim 5 or 6, characterized in that: The second radiation port includes a third impedance matching, a third power divider, a fourth impedance matching, a fourth power divider, a fifth impedance matching, a fifth power divider and four second radiation ports, the four second radiation ports being, from left to right, a second radiation port one, a second radiation port two, a second radiation port three and a second radiation port four. The other end of the second feeder is connected to the input end of the third power divider through the third impedance matching, an output end of the third power divider is connected to the input end of the fourth power divider through the fourth impedance matching, an output end of the fourth power divider is connected to the second radiation port one, another output end of the fourth power divider is connected to the second radiation port two, another output end of the third power divider is connected to the input end of the fifth power divider through the fifth impedance matching, an output end of the fifth power divider is connected to the second radiation port three, and another output end of the fifth power divider is connected to the second radiation port four.

9. A waveguide antenna array based on an unequally divided feeding network according to claim 8, characterized in that: The length of the second radiation port and the second radiation port is 2.8mm, the width of the second radiation port and the second radiation port is 0.9mm, the length of the second radiation port and the second radiation port is 2.8mm, the width of the second radiation port and the second radiation port is 1.6mm, the length of the first radiation port is 2.8mm, the width of the first radiation port is 1.8mm, and the amplitude ratio of the second radiation port, the second radiation port, the first radiation port, the second radiation port and the second radiation port is 0.09:0.13:0.5625:0.13:0.

09.

10. A waveguide antenna array based on an unequally divided feeding network according to claim 9, characterized in that: The center distance between the first radiation port and the second radiation port two or the second radiation port three is 3.3 mm, the center distance between the second radiation port one and the second radiation port two and the center distance between the second radiation port three and the second radiation port four is 3.8 mm.

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