Waveguide slot array and waveguide slot antenna

Abstract

The invention discloses a waveguide slot array and a waveguide slot antenna, and relates to the technical field of antennas. The waveguide slot array comprises a plurality of first waveguide tubes and a plurality of second waveguide tubes, the first waveguide tubes and the second waveguide tubes are identical in structure, each first waveguide tube is provided with a plurality of first waveguide slots, and each second waveguide tube is provided with a plurality of second waveguide slots; wherein the first waveguide tubes and the second waveguide tubes are alternately arranged along a first direction, the first waveguide tubes and the second waveguide tubes are arranged in a staggered manner along a second direction, so that the corresponding first waveguide slots and second waveguide slots are arranged in a staggered manner along the second direction, and the first direction intersects with the second direction. According to the waveguide slot array provided by the invention, the isolation degree of the corresponding waveguide slot antenna can be improved.

Description

Technical Field

[0001] The present application relates to the field of antenna technology, and in particular to a waveguide slot array and a waveguide slot antenna. Background Art

[0002] Waveguide slot antenna refers to an antenna with a caliber that has a slot on the wall of a waveguide tube or cavity resonator, and electromagnetic waves radiate to the outer space through the slot. It is light in weight, simple to process, easy to achieve low side lobes, and can meet the engineering requirements of high reliability, and is widely used in the radar field.

[0003] Currently, a waveguide slot antenna often includes multiple antenna units, and the isolation of the antenna units is a key factor affecting the performance of the waveguide slot antenna. Summary of the invention

[0004] The main purpose of the present application is to propose a waveguide slot array and a waveguide slot antenna, aiming to improve the isolation of the waveguide slot antenna.

[0005] To achieve the above-mentioned purpose, in a first aspect, the present application proposes a waveguide slot array, wherein the waveguide slot array comprises a plurality of first waveguide tubes and a plurality of second waveguide tubes of the same structure, each of the first waveguide tubes is respectively provided with a plurality of first waveguide slots, and each of the second waveguide tubes is respectively provided with a plurality of second waveguide slots;

[0006] The first waveguide tube and the second waveguide tube are alternately arranged along a first direction, and the first waveguide tube and the second waveguide tube are staggered along a second direction so that the corresponding first waveguide slot and the second waveguide slot are staggered along the second direction, wherein the first direction intersects with the second direction.

[0007] In one embodiment, the offset distance between the first waveguide tube and the second waveguide tube is 0.5 to 3 times of the slot spacing, wherein the slot spacing is the spacing between the centers of two adjacent slots of the first waveguide in the second direction.

[0008] In one embodiment, the first waveguide and the second waveguide are ridge waveguides respectively.

[0009] In one embodiment, the first waveguide slots on the first waveguide tube are arranged in a staggered manner, and the second waveguide slots on the second waveguide tube are arranged in a staggered manner.

[0010] In one embodiment, the first waveguide and the second waveguide extend along the second direction respectively, and the distance between the sides of the adjacent first waveguide and the second waveguide on the same side along the first direction is half a working wavelength;

[0011] The distance between the centers of two adjacent first waveguide slots and the distance between the centers of two adjacent second waveguide slots are respectively less than one working wavelength.

[0012] In a second aspect, the present application further provides a waveguide slot antenna, the waveguide slot antenna comprising:

[0013] A horizontal turntable, used to rotate to drive the structure located on the horizontal turntable to rotate synchronously;

[0014] A plurality of phase shifters are located on the horizontal turntable, each of the phase shifters is used to receive a radio frequency input signal;

[0015] The waveguide slot array as described in the first aspect is located on the horizontal turntable, and each of the first waveguide tubes and each of the second waveguide tubes are respectively connected to each of the phase shifters.

[0016] In one embodiment, the waveguide slot antenna also includes a circular polarizer, which includes an adhesive medium layer and a plurality of printed circuit boards, wherein the adhesive medium layer is located between two adjacent printed circuit boards, and the adhesive medium layer is used to bond two adjacent printed circuit boards, and the opposite surfaces of the printed circuit boards are respectively printed with a first metal pattern layer of a first shape and a second metal pattern layer of a second shape, so that the reflected wave between the first metal pattern layer and the second metal pattern layer of the printed circuit board has an initial phase of a target angle, wherein the first shape is different from the second shape, and the target angle is greater than 0° and less than or equal to 90°.

[0017] In one embodiment, the first metal pattern layer includes a first metal wire, a second metal wire, a third metal wire, a fourth metal wire and a fifth metal wire connected in sequence, the first metal wire, the third metal wire and the fifth metal wire extend along a first direction, the second metal wire and the fourth metal wire extend along a second direction, the first metal wire and the fifth metal wire are symmetrical with respect to a center line of the third metal wire, and the second metal wire and the fourth metal wire are symmetrical with respect to a center line of the third metal wire.

[0018] In one embodiment, the second metal pattern layer is a linear metal pattern layer.

[0019] In one embodiment, the second metal pattern layer includes a sixth metal line, a seventh metal line and an eighth metal line, the sixth metal line and the seventh metal line extend along a first direction respectively, the eighth metal line extends along a second direction, the eighth metal line is located between the sixth metal line and the seventh metal line, and connects the sixth metal line and the seventh metal line.

[0020] In one embodiment, the distance between the first metal pattern layer and the second metal pattern layer is one eighth of the working wavelength of the center frequency.

[0021] The above-mentioned waveguide slot array includes a plurality of first waveguide tubes and a plurality of second waveguide tubes, each of the first waveguide tubes is respectively provided with a plurality of first waveguide slots, and each of the second waveguide tubes is respectively provided with a plurality of second waveguide slots, and by staggering the first waveguide tubes and the second waveguide tubes, the first waveguide tubes and the second waveguide tubes are staggered so that the corresponding first waveguide slots and the second waveguide slots are staggered, so that the relative distance between the corresponding first waveguide slots and the second waveguide slots can be increased, and the direct coupling between adjacent first waveguide slots and second waveguide slots can be reduced, so that the electromagnetic field directions of adjacent first waveguide slots and second waveguide slots partially offset each other, which can effectively reduce the energy crosstalk between the first waveguide slots and the second waveguide slots, thereby improving the isolation of the corresponding waveguide slot antenna.

[0022] The above-mentioned waveguide slot antenna includes a horizontal turntable, a plurality of phase shifters and the above-mentioned waveguide slot array. By arranging each phase shifter and the waveguide slot array on the horizontal turntable, the horizontal turntable can drive each phase shifter and the waveguide slot array to rotate, that is, drive the entire waveguide slot antenna to rotate, so as to realize the horizontal plane scanning of the waveguide slot antenna by mechanical scanning. The scanning of the pitch plane of the waveguide slot antenna can be realized by allocating a specific phase combination to each phase shifter, that is, the pitch tracking can be realized by electronic scanning. The waveguide slot antenna is scanned by combining mechanical scanning and electronic scanning, so that the system has a fast capture capability and a certain stable tracking capability. Compared with the two-dimensional arrangement of the electronic scanning antenna in the related art, a large number of components are saved, and only one horizontal turntable is required, which greatly simplifies the structure compared with the two-dimensional turntable of the mechanical scanning antenna. In addition, the isolation of each antenna unit of the waveguide slot antenna of the present application is good, and the waveguide slot antenna has a high performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0024] Figure 1 This is a schematic diagram of the structure of a waveguide slot array in one embodiment of the present application;

[0025] Figure 2 It is a schematic diagram of the relationship between the dislocation distance and the isolation degree;

[0026] Figure 3 It is a schematic diagram of the structure of a rectangular waveguide in the related art;

[0027] Figure 4 is a schematic diagram of the structure of the ridge waveguide;

[0028] Figure 5 This is a schematic diagram of the structure of a waveguide slot antenna in one embodiment of the present application;

[0029] Figure 6 This is a schematic diagram of the mechanical scanning principle of a waveguide slot antenna in one embodiment of the present application;

[0030] Figure 7 This is a schematic diagram of the electrical scanning principle of a waveguide slot antenna in one embodiment of the present application;

[0031] Figure 8 This is a schematic diagram of the structure of a circular polarizer in one embodiment of the present application;

[0032] Fig. 9 It is a schematic diagram of the exploded structure of a circular polarizer in one embodiment of the present application.

[0033] Description of Figure Numbers:

[0034] 1-waveguide slot array, 11-first waveguide tube, 111-first waveguide slot, 12-second waveguide tube, 121-second waveguide slot, 2-horizontal turntable, 3-phase shifter, 4-circular polarizer, 41-printed circuit board, 411-first metal pattern layer, 4111-first metal wire, 4112-second metal wire, 4113-third metal wire, 4114-fourth metal wire, 4115-fifth metal wire, 412-second metal pattern layer, 4121-sixth metal wire, 4122-seventh metal wire, 4123-eighth metal wire, 42-adhesive medium layer.

[0035] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0036] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0037] It should be noted that if the embodiments of the present application 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 status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0038] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present application, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0039] As mentioned in the background technology, a waveguide slot antenna is an antenna with a caliber that has a slot on the wall of a waveguide tube or a cavity resonator, and electromagnetic waves radiate to the outer space through the slot. It is light in weight, simple to process, easy to achieve low side lobes, and can meet the engineering requirements of high reliability, and is widely used in the radar field.

[0040] Currently, a waveguide slot antenna often includes multiple antenna units, and the isolation of the antenna units is a key factor affecting the performance of the waveguide slot antenna.

[0041] In order to solve the above problems, Figure 1 As shown, the present application provides a waveguide slot array 1, which includes a plurality of first waveguide tubes 11 and a plurality of second waveguide tubes 12 with the same structure, each first waveguide tube 11 is respectively provided with a plurality of first waveguide slots 111, and each second waveguide tube 12 is respectively provided with a plurality of second waveguide slots 121. The first waveguide tube 11 and the second waveguide tube 12 can be rectangular waveguide tubes extending along the second direction, respectively, for ease of processing and analysis. The arrangement of the first waveguide slots 111 on the first waveguide tube 11 can be the same as the arrangement of the second waveguide slots 121 on the second waveguide tube 12.

[0042] The first waveguide tube 11 and the second waveguide tube 12 are alternately arranged along the first direction, and the first waveguide tube 11 and the second waveguide tube 12 are staggered along the second direction so that the corresponding first waveguide slots 111 and the second waveguide slots 121 are staggered along the second direction, wherein the first direction intersects the second direction.

[0043] It should be noted that the first direction is the X-axis direction, and the second direction is the Y-axis direction. The first waveguide tube 11 and the second waveguide tube 12 have the same structure, which means that the shape, size and arrangement of the slots on the first waveguide tube 11 and the second waveguide tube 12 are the same. If the first waveguide tube 11 and the second waveguide tube 12 are not staggered along the second direction, the first waveguide slots 111 and the second waveguide slots 121 are arranged in an array 1, and there are first waveguide slots 111 and second waveguide slots 121 located in the same row. In the case where the first waveguide tube 11 and the second waveguide tube 12 are staggered along the second direction, the first waveguide slots 111 and the second waveguide slots 121 originally located in the same row are the corresponding first waveguide slots 111 and the second waveguide slots 121.

[0044] Among them, by alternately arranging the first waveguide tube 11 and the second waveguide tube 12 along the first direction, the first waveguide tube 11 and the second waveguide tube 12 are staggered along the second direction, so that the corresponding first waveguide slots 111 and the second waveguide slots 121 are staggered along the second direction, and the staggered arrangement can pull the relative distance between the corresponding first waveguide slots 111 and the second waveguide slots 121 apart, and can reduce the direct coupling between adjacent first waveguide slots 111 and second waveguide slots 121, so that the electromagnetic field directions of the adjacent first waveguide slots 111 and the second waveguide slots 121 partially offset each other, which can effectively reduce the energy crosstalk between the first waveguide slot 111 and the second waveguide slot 121, thereby improving the isolation of the corresponding waveguide slot antenna.

[0045] For example, Figure 2 As shown, the design bandwidth of the corresponding waveguide slot antenna is 27.5-30 GHz in the Ka high frequency band. It can be seen that as the offset distance d3 gradually increases, the isolation of the waveguide slot antenna is significantly improved.

[0046] The waveguide slot array 1 comprises a plurality of first waveguide tubes 11 and a plurality of second waveguide tubes 12, wherein each first waveguide tube 11 is provided with a plurality of first waveguide slots 111, and each second waveguide tube 12 is provided with a plurality of second waveguide slots 121. By staggering the first waveguide tubes 11 and the second waveguide tubes 12, and staggering the first waveguide tubes 11 and the second waveguide tubes 12, the corresponding first waveguide slots 111 and the second waveguide slots 121 are staggered, so that the relative distance between the corresponding first waveguide slots 111 and the second waveguide slots 121 can be increased, and the direct coupling between adjacent first waveguide slots 111 and the second waveguide slots 121 can be reduced, so that the electromagnetic field directions of the adjacent first waveguide slots 111 and the second waveguide slots 121 partially offset each other, and the energy crosstalk between the first waveguide slots 111 and the second waveguide slots 121 can be effectively reduced, thereby improving the isolation of the corresponding waveguide slot antenna.

[0047] In one embodiment, the offset distance between the first waveguide 11 and the second waveguide 12 is 0.5 to 3 times the gap spacing, wherein the gap spacing is the spacing between the centers of two adjacent first waveguide gaps 111 in the second direction. Figure 1 As shown, the offset distance between the first waveguide 11 and the second waveguide 12 is Figure 1 The gap spacing is Figure 1 d2 in.

[0048] It can be understood that the relative distance between the corresponding first waveguide slot 111 and the second waveguide slot 121 is positively correlated with the offset distance between the first waveguide tube 11 and the second waveguide tube 12, and within a certain range, the larger the relative distance between the corresponding first waveguide slot 111 and the second waveguide slot 121, that is, the larger the offset distance between the first waveguide tube 11 and the second waveguide tube 12, the better the isolation improvement of the waveguide slot antenna will be. However, the larger the offset distance between the first waveguide tube 11 and the second waveguide tube 12 will result in a larger size of the waveguide slot array 1, and an overly large waveguide slot array 1 is not conducive to the miniaturization of the waveguide slot antenna. Therefore, setting the offset distance between the first waveguide tube 11 and the second waveguide tube 12 to 0.5 to 3 times the slot spacing can significantly improve the isolation of the corresponding waveguide slot antenna and prevent the size of the waveguide slot array 1 from being too large.

[0049] In one embodiment, the first waveguide tube 11 and the second waveguide tube 12 extend along the first direction respectively, and the distance between the sides of the adjacent first waveguide tube 11 and the second waveguide tube 12 along the second direction is half of the working wavelength. The distance between the centers of two adjacent first waveguide slots 111 and the distance between the centers of two adjacent second waveguide slots 121 are respectively less than one working wavelength.

[0050] Among them, Figure 1 As shown, the distance between the adjacent first waveguide 11 and the second waveguide 12 on the same side along the second direction is Figure 1 In d3, the distance between the centers of two adjacent first waveguide slots 111 and the distance between the centers of two adjacent second waveguide slots 121 are respectively Figure 1 d2 in.

[0051] Among them, when considering the scanning range of the waveguide slot antenna in the pitch plane, the distance between the adjacent first waveguide tubes 11 and the second waveguide tubes 12 is a key factor. From the antenna array theory, it can be known that the spacing between adjacent antenna units will affect the beam scanning characteristics. For the waveguide slot antenna, in order to achieve a wider scanning range (such as + / -60°) in the pitch plane, it is necessary to control the distance between the adjacent first waveguide tubes 11 and the second waveguide tubes 12. When d3 is approximately half of the working wavelength, the interference principle between the antenna units can be used to achieve a wider scanning range. According to the directional pattern product theorem, the directional pattern of the antenna array is the product of the unit antenna directional pattern and the array factor directional pattern. In the pitch plane direction, a suitable d3 can make the array factor directional pattern vary within a wider angle range, thereby achieving a wider scanning angle.

[0052] Grating lobes are unwanted side lobes in the antenna pattern, and their levels may be comparable to or even higher than the main lobe, which will have a serious impact on the performance of the antenna. In order to avoid the appearance of grating lobes or reduce the level of grating lobes, d2 needs to be limited. According to antenna theory, when the distance between adjacent slots is less than one working wavelength, the grating lobe situation of the antenna pattern can be effectively improved. Therefore, by limiting the distance between the centers of the two adjacent first waveguide slots 111 and the distance between the centers of the two adjacent second waveguide slots 121 to be less than one working wavelength, the appearance of grating lobes can be avoided or the level of grating lobes can be reduced, thereby improving the performance of the corresponding waveguide slot antenna.

[0053] In one embodiment, the first waveguide 11 and the second waveguide 12 are ridge waveguides. Figure 3 and Figure 4 As shown, Figure 3 It is a common rectangular waveguide in the related art. Figure 4 It is a ridge waveguide, which adds a ridge-shaped structure inside the rectangular waveguide.

[0054] Among them, the ridge waveguide adds a ridge-like structure inside the waveguide. Taking the rectangular ridge waveguide as an example, a ridge is added at the center of the wide side of the rectangular waveguide or other suitable positions. The shape of the ridge can be rectangular, triangular, etc. The existence of these ridges changes the electromagnetic field distribution inside the waveguide.

[0055] Due to its special structure, the ridge waveguide changes the electromagnetic field distribution, so that the cutoff frequency is reduced and the frequency band is widened. Therefore, the operating frequency range of the ridge waveguide is wider. Moreover, the electromagnetic field distribution inside the ridge waveguide is conducive to reducing the reflection and scattering of electromagnetic waves on the waveguide wall, which is conducive to reducing energy loss and improving the efficiency of signal transmission. Therefore, setting the first waveguide 11 and the second waveguide 12 as ridge waveguides is conducive to improving the frequency range supported by the waveguide slot array 1 and the efficiency of signal transmission. In addition, setting the first waveguide 11 and the second waveguide 12 as ridge waveguides is also conducive to limiting the distance d3 between adjacent waveguides in the first waveguide 11 and the second waveguide 12 to about half an operating wavelength, and making the spacing d2 between adjacent first waveguide slots 111 and adjacent second waveguide slots 121 less than one operating wavelength, so as to facilitate the corresponding waveguide slot antenna to obtain a wider scanning range in the pitch plane, avoid the appearance of grating lobes or reduce the level of grating lobes.

[0056] In one embodiment, Figure 1 As shown, the first waveguide slots 111 on the first waveguide tube 11 are arranged in a staggered manner, and the second waveguide slots 121 on the second waveguide tube 12 are arranged in a staggered manner.

[0057] The first waveguide slots 111 on the first waveguide tube 11 are arranged in a staggered manner, and the first waveguide slots 111 are arranged alternately in the second direction (column direction), and the first waveguide slots 111 adjacent to each other in the vertical direction are staggered in the first direction (row direction). Similarly, the second waveguide slots 121 on the second waveguide tube 12 are also arranged in a staggered manner, and the second waveguide slots 121 adjacent to each other in the vertical direction are staggered in the first direction (row direction).

[0058] In this embodiment, by staggering the first waveguide slots 111 on the first waveguide tube 11, the direct coupling between adjacent first waveguide slots 111 can be reduced, and by staggering the second waveguide slots 121 on the second waveguide tube 12, the direct coupling between adjacent second waveguide slots 121 can be reduced, thereby improving the isolation of the corresponding waveguide slot antenna.

[0059] In one embodiment, Figure 5 As shown, the present application also provides a waveguide slot antenna, which includes: a horizontal turntable 2, a plurality of phase shifters 3 and a waveguide slot array 1 as in any of the above embodiments.

[0060] The horizontal turntable 2 is used to rotate to drive the structure on the horizontal turntable 2 to rotate synchronously. Each phase shifter 3 is located on the horizontal turntable 2, and each phase shifter 3 is used to receive a radio frequency input signal; the waveguide slot array 1 is located on the horizontal turntable 2, and each first waveguide tube 11 and each second waveguide tube 12 in the waveguide slot array 1 are respectively connected to each phase shifter 3.

[0061] Among them, the horizontal turntable 2 is a mechanical device that can rotate around a vertical axis. The horizontal turntable 2 may include a base, a turntable, a drive system, and a positioning system. The base is usually a stable platform that provides solid support for the entire turntable. The turntable is the part where the object to be rotated is placed. It is connected to the base through bearings and other components to ensure the smoothness of rotation. The drive system includes components such as a motor and a reducer. The motor provides power, and the reducer is used to adjust the speed and torque so that the turntable can rotate at an appropriate speed and force. The positioning system is used to accurately control the rotation angle of the turntable. The positioning system may include devices such as photoelectric encoders and rotary transformers, which can accurately feedback the position information of the turntable.

[0062] The phase shifter 3 is an electronic device that can change the phase of a signal. The basic principle is to achieve a change in phase by changing parameters such as the length, capacitance, and inductance of the signal transmission path. For example, in a simple transmission line phase shifter, the signal passes through transmission lines of different lengths. Due to the different lengths of the transmission lines, the signal propagation time is different, resulting in a change in phase. In the waveguide slot antenna, by connecting each phase shifter 3 to each first waveguide tube 11 and each second waveguide tube 12 respectively, each phase shifter 3 can control the phase of the corresponding antenna unit based on the input RF input signal, thereby adjusting the direction of the antenna beam of the waveguide slot antenna. In addition, by changing the phase of each antenna unit in the waveguide slot antenna, beam scanning, focusing and other functions can be achieved, thereby improving the coverage range and signal reception quality of the communication system.

[0063] In satellite communications, beam scanning for fast aiming and tracking usually occurs primarily in one dimension, so the higher scanning speed brought by electronic scanning only needs to occur in one dimension, while the other dimension can be scanned more slowly by mechanical scanning. Figure 1 and Figure 6As shown, by arranging each phase shifter 3 and the waveguide slot array 1 on the horizontal turntable 2, the horizontal turntable 2 can drive each phase shifter 3 and the waveguide slot array 1 to rotate, that is, drive the entire waveguide slot antenna to rotate, so as to realize the horizontal plane scanning of the waveguide slot antenna by mechanical scanning. As for the pitch tracking, the electronic scanning method is adopted, and the scanning of the pitch plane of the waveguide slot antenna can be realized by assigning a specific phase combination to each phase shifter 3. The waveguide slot antenna is scanned by combining mechanical scanning and electronic scanning, so that the system has a fast capture capability and a certain stable tracking capability. Moreover, the waveguide slot antenna of this embodiment saves a large number of components compared with the two-dimensional arrangement of the electronic scanning antenna in the related art, and only requires a horizontal turntable 2, which greatly simplifies the structure compared with the two-dimensional turntable of the mechanical scanning antenna in the related art. At the same time, the antenna adopts a low-profile waveguide slot form, which greatly improves the working bandwidth compared with the VICTS antenna with the same low profile but less than 5% bandwidth.

[0064] The electric scanning principle block diagram of this application is as follows Figure 7 As shown, an 8*8 antenna array is taken as an example. The waveguide slot antenna includes 8 antenna subarrays (antenna units), each antenna subarray contains 8 antenna elements (waveguide slots). A phase shifter 3 is connected behind each subarray, and the phase shifter 3 can control the phase state of the antenna subarray connected to the phase shifter 3. Assume that the phase of the phase shifter 31 is The phase of the phase shifter 32 is The phase of phase shifter 3i is The corresponding antenna beam tilt angle θ can be calculated by the following formula.

[0065]

[0066] In the above formula, k is the free space beam, and d is the distance between adjacent antenna elements. It should be noted that d is Figure 1 When d2 in the calculation is the horizontal antenna beam tilt angle, d is Figure 1 When d3 in , the calculated antenna beam tilt angle is the vertical antenna beam tilt angle, and the final antenna beam tilt angle is determined by the horizontal antenna beam tilt angle and the vertical antenna beam tilt angle. The scanning angle of the waveguide slot antenna in the horizontal plane is completely controlled by the mechanical turntable, and an equivalent relationship is presented, that is, the rotation angle of the turntable is the horizontal scanning angle of the antenna beam, such as Figure 7 shown.

[0067] It should also be noted that, since the waveguide slot antenna includes the waveguide slot array 1 of any of the above embodiments, the isolation of the antenna units of the waveguide slot antenna of this embodiment is good, and the waveguide slot antenna has higher performance.

[0068] The above-mentioned waveguide slot antenna includes a horizontal turntable 2, a plurality of phase shifters 3 and the above-mentioned waveguide slot array 1. By arranging each phase shifter 3 and the waveguide slot array 1 on the horizontal turntable 2, the horizontal turntable 2 can drive each phase shifter 3 and the waveguide slot array 1 to rotate, that is, drive the entire waveguide slot antenna to rotate, so as to realize the horizontal plane scanning of the waveguide slot antenna by mechanical scanning. The scanning of the pitch plane of the waveguide slot antenna can be realized by allocating a specific phase combination to each phase shifter 3, that is, the pitch tracking can be realized by electronic scanning. The waveguide slot antenna is scanned by combining mechanical scanning and electronic scanning, so that the system has a fast capture capability and a certain stable tracking capability. Compared with the two-dimensional arrangement of the electronic scanning antenna in the related art, a large number of components are saved, and only one horizontal turntable 2 is required, which greatly simplifies the structure compared with the two-dimensional turntable of the mechanical scanning antenna. In addition, the isolation of each antenna unit of the waveguide slot antenna of the present application is good, and the waveguide slot antenna has a high performance.

[0069] In one embodiment, Figure 8 and Fig. 9 As shown, the waveguide slot antenna also includes a circular polarizer 4, which includes an adhesive medium layer 42 and a plurality of printed circuit boards 41. The adhesive medium layer 42 is located between two adjacent printed circuit boards 41, and the adhesive medium layer 42 is used to bond two adjacent printed circuit boards 41. The opposite surfaces of the printed circuit boards 41 are respectively printed with a first metal pattern layer 411 of a first shape and a second metal pattern layer 412 of a second shape, so that the reflected wave between the first metal pattern layer 411 and the second metal pattern layer 412 of the printed circuit board 41 has an initial phase of a target angle, wherein the first shape is different from the second shape, and the target angle is greater than 0° and less than or equal to 90°.

[0070] In the related art, the adjacent metal pattern layers of the circular polarizer 4 mostly use a quarter wavelength spacing. This is because the metal patterns of each layer of the circular polarizer 4 are completely consistent, and the electromagnetic waves reflected back from the layers are exactly offset after passing through two quarter wavelengths, thereby ensuring the smooth transmission of the electromagnetic waves. However, the total thickness of the circular polarizer 4 of this structure is relatively high, which is not conducive to reducing the volume of the circular polarizer. Taking the Ka band as an example, the total thickness of the quarter wavelength circular polarizer 4 of the related art can reach 2.5 mm.

[0071] In this embodiment, a first metal pattern layer 411 with a first shape and a second metal pattern layer 412 with a second shape are respectively printed on opposite surfaces of the printed circuit board 41, so that the reflected waves between the first metal pattern layer 411 and the second metal pattern layer 412 of the printed circuit board 41 have an initial phase at a target angle. The initial phase at the target angle corresponds to a certain spatial distance. For example, an initial phase of 90° is equivalent to the phase corresponding to a spatial distance of a quarter wavelength. Then, by setting the first metal pattern layer 411 and the second metal pattern layer 412 with different shapes, the layer spacing between the first metal pattern layer 411 and the second metal pattern layer 412 can be compressed to at most half of the original, that is, the circular polarizer 4 can reduce the overall profile height, which is beneficial to the miniaturization and thinning of the waveguide slot antenna.

[0072] In one embodiment, as Fig. 9 shown, the first metal pattern layer 411 includes a first metal wire 4111, a second metal wire 4112, a third metal wire 4113, a fourth metal wire 4114, and a fifth metal wire 4115 connected in sequence. The first metal wire 4111, the third metal wire 4113, and the fifth metal wire 4115 extend along a first direction, the second metal wire 4112 and the fourth metal wire 4114 extend along a second direction, the first metal wire 4111 and the fifth metal wire 4115 are symmetric with respect to the center line of the third metal wire 4113, and the second metal wire 4112 and the fourth metal wire 4114 are symmetric with respect to the center line of the third metal wire 4113.

[0073] As shown in the figure, the first metal pattern layer 411 is a metal pattern layer in the shape of a "Ji" character. The metal pattern layer of this shape is composed of multiple bent parts, and these bent parts play a key role in guiding electromagnetic signals and generating circular polarization characteristics.

[0074] It can be understood that the first metal pattern layer 411 includes a first metal wire 4111, a second metal wire 4112, a third metal wire 4113, a fourth metal wire 4114, and a fifth metal wire 4115 connected in sequence. Parameters such as the width, length, the bending angle and spacing of the "Ji" character of these metal wires can all be designed and adjusted to achieve specific electromagnetic performance. The "Ji" character metal pattern can excite electric field components in different directions.

[0075] In applications, the first metal pattern layer 411 can also be a metal pattern layer with other bent shapes.

[0076] In one embodiment, the second metal pattern layer 412 is a straight metal pattern layer.

[0077] In the application, through testing, it is found that when the first metal pattern layer 411 is a metal pattern layer in the shape of a Chinese character 'ji' (a shape similar to 'ji'), and the second metal pattern layer 412 is a straight-line (i.e., in the shape of a Chinese character 'yi') metal pattern layer, the reflected wave between the first metal pattern layer 411 and the second metal pattern layer 412 will obtain an initial phase of 90°, which is equivalent to the phase corresponding to a spatial distance of a quarter wavelength. This can compress the layer spacing between the first metal pattern layer 411 and the second metal pattern layer 412 to half of the original, that is, one-eighth wavelength, thereby reducing the overall profile height of the circular polarizer 4.

[0078] In another embodiment, as Fig. 9 shown, the second metal pattern layer 412 includes a sixth metal wire 4121, a seventh metal wire 4122, and an eighth metal wire 4123. The sixth metal wire 4121 and the seventh metal wire 4122 extend along the first direction respectively, the eighth metal wire 4123 extends along the second direction, and the eighth metal wire 4123 is located between the sixth metal wire 4121 and the seventh metal wire 4122 and connects the sixth metal wire 4121 and the seventh metal wire 4122.

[0079] Among them, as shown in the figure, the second metal pattern layer 412 is a metal pattern layer in the shape of a Chinese character 'gong' (a shape similar to 'gong').

[0080] In the application, through testing, it is found that when the first metal pattern layer 411 is a metal pattern layer in the shape of a Chinese character 'ji' (a shape similar to 'ji'), and the second metal pattern layer 412 is a metal pattern layer in the shape of a Chinese character 'gong' (a shape similar to 'gong'), the reflected wave between the first metal pattern layer 411 and the second metal pattern layer 412 will also obtain an initial phase of 90°, which is equivalent to the phase corresponding to a spatial distance of a quarter wavelength. This can compress the layer spacing between the first metal pattern layer 411 and the second metal pattern layer 412 to half of the original, that is, one-eighth wavelength, thereby reducing the overall profile height of the circular polarizer 4.

[0081] It should be noted that in the application, the second metal pattern layer 412 can also be of other shapes, as long as the first shape is different from the second shape, and the reflected wave between the first metal pattern layer 411 and the second metal pattern layer 412 of the printed circuit board 41 has an initial phase with a target angle.

[0082] In one embodiment, the distance between the first metal pattern layer 411 and the second metal pattern layer 412 is one-eighth of the working wavelength of the center frequency point.

[0083] Exemplarily, the waveguide slot antenna of this embodiment may include 4 metal pattern layers. Under the condition of meeting the 10% working bandwidth, the working wavelength between the first metal pattern layer 411 and the second metal pattern layer 412 is reduced to one eighth of the central frequency, and the structure of the circular polarizer 4 is relatively compact, which is conducive to the miniaturization and thinness of the waveguide slot antenna. Taking the Ka band as an example, the total thickness of the quarter-wavelength circular polarizer 4 of the related art can reach 2.5mm, and after adopting this compact structure, the size can be compressed to 1.22mm, about half.

[0084] The above description is only an exemplary embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A waveguide slot array, characterized in that: The waveguide slot array comprises a plurality of first waveguide tubes and a plurality of second waveguide tubes of the same structure, each of the first waveguide tubes is provided with a plurality of first waveguide slots, and each of the second waveguide tubes is provided with a plurality of second waveguide slots; The first waveguide tube and the second waveguide tube are alternately arranged along a first direction, and the first waveguide tube and the second waveguide tube are staggered along a second direction so that the corresponding first waveguide slot and the second waveguide slot are staggered along the second direction, wherein the first direction intersects with the second direction.

2. The waveguide slot array according to claim 1, characterized in that: The offset distance between the first waveguide tube and the second waveguide tube is 0.5 to 3 times of the slot spacing, wherein the slot spacing is the spacing between the centers of two adjacent slots of the first waveguide in the second direction.

3. The waveguide slot array according to claim 1, characterized in that: The first waveguide and the second waveguide are ridge waveguides respectively.

4. The waveguide slot array according to claim 1, characterized in that: The first waveguide slots on the first waveguide tube are arranged in a staggered manner, and the second waveguide slots on the second waveguide tube are arranged in a staggered manner.

5. The waveguide slot array according to any one of claims 1 to 4, characterized in that: The first waveguide and the second waveguide extend along the second direction respectively, and the distance between the sides of the adjacent first waveguide and the second waveguide on the same side along the first direction is half a working wavelength; The distance between the centers of two adjacent first waveguide slots and the distance between the centers of two adjacent second waveguide slots are respectively less than one working wavelength.

6. A waveguide slot antenna, characterized in that: The waveguide slot antenna comprises: A horizontal turntable, used to rotate to drive the structure located on the horizontal turntable to rotate synchronously; A plurality of phase shifters are located on the horizontal turntable, each of the phase shifters is used to receive a radio frequency input signal; The waveguide slot array according to any one of claims 1 to 5 is located on the horizontal turntable, and each of the first waveguide tubes and each of the second waveguide tubes are respectively connected to each of the phase shifters.

7. The waveguide slot antenna according to claim 6, wherein: The waveguide slot antenna also includes a circular polarizer, which includes an adhesive medium layer and a plurality of printed circuit boards. The adhesive medium layer is located between two adjacent printed circuit boards, and the adhesive medium layer is used to bond two adjacent printed circuit boards. A first metal pattern layer of a first shape and a second metal pattern layer of a second shape are printed on opposite surfaces of the printed circuit boards, respectively, so that the reflected wave between the first metal pattern layer and the second metal pattern layer of the printed circuit boards has an initial phase of a target angle, wherein the first shape is different from the second shape, and the target angle is greater than 0° and less than or equal to 90°.

8. The waveguide slot antenna according to claim 7, characterized in that: The first metal pattern layer includes a first metal wire, a second metal wire, a third metal wire, a fourth metal wire and a fifth metal wire connected in sequence, the first metal wire, the third metal wire and the fifth metal wire extend along a first direction, the second metal wire and the fourth metal wire extend along a second direction, the first metal wire and the fifth metal wire are symmetrical with respect to a center line of the third metal wire, and the second metal wire and the fourth metal wire are symmetrical with respect to a center line of the third metal wire.

9. The waveguide slot antenna according to claim 7, characterized in that: The second metal pattern layer is a linear metal pattern layer; or The second metal pattern layer includes a sixth metal line, a seventh metal line and an eighth metal line, the sixth metal line and the seventh metal line extend along a first direction respectively, the eighth metal line extends along a second direction, the eighth metal line is located between the sixth metal line and the seventh metal line, and connects the sixth metal line and the seventh metal line.

10. The waveguide slot antenna according to claim 7, wherein: The distance between the first metal pattern layer and the second metal pattern layer is one eighth of the working wavelength of the center frequency.

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