Large-frequency-ratio dual-circularly-polarized scanning antenna based on SIW slot array

Abstract

The invention discloses a large-frequency-ratio dual-circularly-polarized scanning antenna based on an SIW slot array. The antenna comprises a first dielectric plate, a second dielectric plate, a staggered grid-shaped patch array, a dipole array, a microwave feed patch, a millimeter wave slot array patch, a metal through hole, a microwave feed probe and a metal floor. A staggered grid-shaped patch array, a dipole array and a microwave feed patch are printed on the upper surface of the first dielectric plate; an air cavity is formed between the second dielectric plate and the first dielectric plate; a millimeter wave slot array patch is printed on the upper surface of the second dielectric plate; millimeter wave SIW gaps which are distributed in a staggered mode are formed in the millimeter wave gap array patch and correspond to dipoles of the dipole array in a one-to-one mode. A metal floor is arranged on the lower surface of the second dielectric plate, and a feed circular hole for the microwave feed probe to pass through is etched in the metal floor; and the microwave feed probe is connected with the microwave feed patch. The invention has the advantages of large frequency ratio, miniaturization, millimeter wave scanning and the like.

Description

Technical Field

[0001] The invention relates to the technical field of communication antennas, and in particular to a large frequency ratio dual circular polarization scanning antenna based on a SIW slot array. Background Art

[0002] Both terrestrial mobile communications and satellite communications contain a large number of microwave and millimeter wave frequency bands to meet the needs of different application scenarios. As communication equipment continues to develop towards multifunctionality, lightweight and miniaturization, the space for placing antennas is also constantly compressed. The use of cross-band fusion antennas that can work in both microwave and millimeter wave frequency bands can not only meet the needs of different scenarios, but also effectively alleviate the space problem of coexistence of microwave antennas and millimeter wave antennas.

[0003] At the same time, compared with linearly polarized antennas, circularly polarized antennas can provide a stable link between the transmitting antenna and the receiving antenna, and have the ability to improve multipath distortion and polarization mismatch, and have important applications in wireless communications, radar, electronic reconnaissance and electronic jamming. Therefore, how to design a dual-frequency circularly polarized antenna that can work in both the microwave band and the millimeter wave band has become an important topic in the field of communications.

[0004] However, with respect to the disclosed dual-frequency antenna technologies and structures for microwave and millimeter wave operating frequency bands, there are still the following problems.

[0005] 1. The polarization mode of dual-frequency antennas integrating microwave and millimeter wave working frequency bands is linear polarization, while the working frequency ratio of dual-frequency circularly polarized antennas is not large enough and cannot work in microwave and millimeter wave bands at the same time.

[0006] 2. Dual-frequency antennas that integrate microwave and millimeter-wave operating frequency bands do not take into account the scanning performance of millimeter waves, and almost no dual-frequency antennas can scan millimeter waves. Summary of the invention

[0007] The purpose of the present invention is to overcome the shortcomings and deficiencies of the prior art and provide a large frequency ratio dual circular polarization scanning antenna based on a SIW slot array. The antenna is a compact and scannable dual-frequency antenna integrating microwave and millimeter wave working frequency bands, which can achieve circular polarization performance in both microwave and millimeter wave frequency bands.

[0008] To achieve the above-mentioned purpose, the technical solution provided by the present invention is: a large frequency ratio dual circular polarization scanning antenna based on SIW slot array, comprising a first dielectric plate, a second dielectric plate, a staggered grid patch array, a dipole array, a microwave feeding patch, a millimeter wave SIW slot array patch, a metal through hole, a microwave feeding probe and a metal floor; the upper surface of the first dielectric plate is printed with a staggered grid patch array, a dipole array and a microwave feeding patch; the second dielectric plate is located directly below the first dielectric plate, and a distance is maintained between the first dielectric plate and the second dielectric plate to form an air cavity; the upper surface of the second dielectric plate is printed with a millimeter wave SIW slot array patch, and the millimeter wave SIW slot array Millimeter-wave SIW slots are formed on the column patches, and one millimeter-wave SIW slot corresponds to a dipole of the dipole array, and the center of each millimeter-wave SIW slot coincides with the center of the corresponding dipole. The linear polarization radiation of the millimeter-wave SIW slot is converted into circular polarization radiation through the dipole, so as to achieve circular polarization scanning performance in the millimeter-wave frequency band; a metal floor is arranged on the lower surface of the second dielectric plate, and a feeding circular hole for a microwave feeding probe to pass through is etched on the metal floor; the microwave feeding probe is connected to the microwave feeding patch, and an excitation signal is coupled to the staggered grid patch array to excite the staggered grid patch array to radiate, so as to form a patch antenna structure working in the microwave band.

[0009] Preferably, the staggered grid patch array comprises a plurality of square grid units arranged in a periodic array, and the line width of the outer frame of the staggered grid patch array is half of the line width of the inner square grid units.

[0010] Preferably, the four corners of the staggered grid patch array are all cut to form perturbations to achieve microwave circular polarization.

[0011] Preferably, the dipole array is an n×n array, each square grid unit of the staggered grid patch array has a dipole, each dipole is located on a diagonal of the square grid unit, and the center of the dipole coincides with the center of the corresponding square grid unit.

[0012] Preferably, the dipole array and the staggered grid patch array are nested with each other.

[0013] Preferably, the millimeter-wave SIW slot array patch is an n×n slot array, which is independently fed by n millimeter-wave feeding ports, that is, a column of slots is independently fed by a millimeter-wave feeding port, and there is a phase difference between two adjacent millimeter-wave feeding ports, and they are excited at the same time to achieve linear polarization scanning performance in the millimeter-wave frequency band, and then through polarization conversion of the dipole array, circular polarization scanning performance in the millimeter-wave band is achieved.

[0014] Preferably, the upper end of the microwave feeding probe passes through the metal floor, the second dielectric plate and the first dielectric plate in sequence and is electrically connected to the microwave feeding patch; the microwave feeding patch couples the excitation signal to the staggered grid patch array to excite the patch radiation mode of the staggered grid patch array to achieve radiation in the microwave frequency band.

[0015] Compared with the prior art, the present invention has the following advantages and beneficial effects: 1. The present invention integrates two structures working in different frequency bands into a composite radiation structure by exciting the upper polarization surface.

[0016] 2. The present invention converts a linearly polarized antenna into a circularly polarized antenna through a simple polarization rotating dipole, and uses the phase difference between the ports to perform beam control, thereby achieving a larger-angle circular polarization scanning of millimeter waves, with a scanning angle of about 40 degrees. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is an exploded diagram of a large frequency ratio dual circular polarization scanning antenna provided by an embodiment of the present invention.

[0018] Figure 2 4 is a structural diagram of the upper surface of the first dielectric plate in an embodiment of the present invention.

[0019] Figure 3 4 is a structural diagram of a millimeter wave SIW slot array patch, a metal through hole, and a metal floor in an embodiment of the present invention.

[0020] Figure 4 This is the S-parameter simulation result diagram of the large frequency ratio dual circular polarization scanning antenna.

[0021] Figure 5 This is a simulation result diagram of the axial ratio and gain of the large frequency ratio dual circularly polarized scanning antenna in the millimeter wave frequency band.

[0022] Figure 6 This is a simulation result diagram of the axial ratio and gain of the large frequency ratio dual circularly polarized scanning antenna in the microwave frequency band.

[0023] Figure 7 This is the simulation result of the radiation pattern of the large frequency ratio dual circular polarization scanning antenna in the millimeter wave frequency band of 25GHz.

[0024] Figure 8 This is the simulation result of the radiation pattern of the large frequency ratio dual circular polarization scanning antenna in the microwave frequency band of 3.2GHz.

[0025] Fig. 9 It is the array beam and axial ratio diagram of the large frequency ratio dual circularly polarized scanning antenna at 24.9GHz. DETAILED DESCRIPTION

[0026] The present invention is further described in detail below in conjunction with embodiments and drawings, but the embodiments of the present invention are not limited thereto.

[0027] like Figure 1 As shown, this embodiment discloses a large frequency ratio dual circular polarization scanning antenna based on SIW slot array, comprising a first dielectric plate 11, a second dielectric plate 12, a staggered grid patch array 21, a dipole array 22, a microwave feeding patch 3, a millimeter wave SIW slot array patch 4, a metal through hole 5, a microwave feeding probe 6 and a metal floor 7; the upper surface of the first dielectric plate 11 is printed with a staggered grid patch array 21, a dipole array 22 and a microwave feeding patch 3; the second dielectric plate 12 is located directly below the first dielectric plate 11, and a distance is maintained between the first dielectric plate 11 and the second dielectric plate 12 to form an air cavity; the upper surface of the second dielectric plate 12 is printed with a millimeter wave SIW slot array patch 4, and the millimeter wave SIW slot array patch 4 is formed with staggered millimeter wave SIW slots 41, and a millimeter wave SIW slot The gap 41 corresponds to a dipole 221 of the dipole array 22, and the center of each millimeter wave SIW gap 41 coincides with the center of the corresponding dipole 221. The linear polarization radiation of the millimeter wave SIW gap 41 is converted into circular polarization radiation through the dipole 221, so as to realize the circular polarization scanning performance of the millimeter wave frequency band. A metal floor 7 is arranged on the lower surface of the second dielectric plate 12, and a feeding circular hole for the microwave feeding probe 6 to pass through is etched on the metal floor 7. The upper end of the microwave feeding probe 6 passes through the metal floor 7, the second dielectric plate 12 and the first dielectric plate 11 in sequence and is electrically connected to the microwave feeding patch 3. The microwave feeding patch 3 couples the excitation signal to the staggered grid patch array 21, excites the patch radiation mode of the staggered grid patch array 21, realizes the radiation in the microwave frequency band, and forms a patch antenna structure working in the microwave band.

[0028] like Figure 2As shown, the staggered grid patch array 21 includes a number of square grid units arranged in a periodic array, and the outer frame line width of the staggered grid patch array 21 is half the line width of the inner square grid unit; the four corners of the staggered grid patch array 21 are all cut corners to form perturbations to achieve microwave circular polarization; the second dielectric plate 12 and the staggered grid patch array 21 constitute a microwave circular polarization radiation unit, and the microwave circular polarization radiation unit is coupled and fed by the microwave feeding patch 3. The dipole array 22 is a 6×6 array, and each square grid unit of the staggered grid patch array 21 has a dipole 221, and each dipole 221 is located on a diagonal of the square grid unit, and the center of the dipole 221 coincides with the center of the corresponding square grid unit. The dipole array 22 and the staggered grid patch array 21 are nested with each other to form a millimeter wave polarization converter.

[0029] like Figure 3 As shown, the millimeter wave SIW slot array patch 4 is a 6×6 slot array, which is independently fed by 6 millimeter wave feeding ports 42, that is, a column of slots is independently fed by a millimeter wave feeding port 42, and there is a phase difference between two adjacent millimeter wave feeding ports 42, and they are excited at the same time to achieve linear polarization scanning performance in the millimeter wave frequency band, and then after polarization conversion by the dipole array 22, circular polarization scanning performance in the millimeter wave band is achieved; beam control in the millimeter wave frequency band is achieved by changing the phase difference between the millimeter wave feeding ports 42 to form a scannable millimeter wave circular polarization array; the second dielectric plate 12, the metal floor 7, the millimeter wave SIW slot array patch 4, the first dielectric plate 11, the dipole array 22 and the staggered grid patch array 21 constitute a millimeter wave circularly polarized radiation unit.

[0030] Specifically, the length and width of the first dielectric plate 11 and the second dielectric plate 12 are both 46 mm, the thickness is 0.508 mm, the material is Rogers5880, the dielectric constant is 2.2, and the loss tangent is 0.0009. The length and width of the millimeter wave SIW slot array patch 4 are 41.9 mm and 336 mm respectively; the length and width of the millimeter wave slot are 4 mm and 0.45 mm respectively. The length and width of the microwave feeding patch 3 are 25 mm and 2 mm respectively. The length and width of the dipole 221 of the dipole array 22 are 3.2 mm and 1.5 mm respectively. The length and width of the square grid unit of the hollow part of the staggered grid patch array 21 are 4.8 mm respectively. The height of the air cavity between the first dielectric plate 11 and the second dielectric plate 12 is 2.5 mm.

[0031] like Figure 4As shown, the simulation and measured S parameters of the large frequency ratio dual circular polarization scanning antenna of this embodiment are given, and the impedance bandwidths of |S11|<-10dB in the two working frequency bands are 4.3% (3.15GHz-3.29GHz) and 3.6% (24.6GHz-25.5GHz).

[0032] like Figure 5 As shown, the axial ratio and gain performance of the large frequency ratio dual circular polarization scanning antenna in the millimeter wave band of the embodiment are simulated and measured. When working in the millimeter wave band, the 3dB axial ratio bandwidth is measured to be 2.68% (24.83 ~ 25.5GHz). The measured peak gain at 25.5 GHz is 19.5 dBic.

[0033] like Figure 6 As shown, the simulation results of the axial ratio and gain of the large frequency ratio dual circular polarization scanning antenna in the microwave frequency band of this embodiment are given. When working in the microwave frequency band, the 3 dB axial ratio bandwidth is measured to be 0.63% (3.18-3.2 GHz), and the measured peak gain at 3.18 GHz is 8.18 dBic.

[0034] like Figure 7 and Figure 8 As shown, simulation results of the radiation patterns of the large frequency ratio dual circular polarization scanning antenna of this embodiment in the 25 GHz millimeter wave frequency band and the 3.2 GHz microwave frequency band are respectively given.

[0035] like Fig. 9 As shown, the beam and axial ratio of the circular polarization antenna array of the large frequency ratio dual circular polarization scanning antenna at 24.9 GHz in this embodiment are given. It can be seen that within the scanning angle range of (0°, 40°), all beams meet the gain drop within 3 dB and achieve an axial ratio of less than 3 dB.

[0036] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A high frequency ratio dual circular polarization scanning antenna based on SIW slot array, characterized in that: The invention comprises a first dielectric plate (11), a second dielectric plate (12), a staggered grid patch array (21), a dipole array (22), a microwave feeding patch (3), a millimeter wave SIW slot array patch (4), a metal through hole (5), a microwave feeding probe (6) and a metal floor (7); the staggered grid patch array (21), the dipole array (22) and the microwave feeding patch (3) are printed on the upper surface of the first dielectric plate (11); the second dielectric plate (12) is located directly below the first dielectric plate (11), The first dielectric plate (11) and the second dielectric plate (12) are spaced apart from each other to form an air cavity; a millimeter wave SIW slot array patch (4) is printed on the upper surface of the second dielectric plate (12); staggered millimeter wave SIW slots (41) are formed on the millimeter wave SIW slot array patch (4); one millimeter wave SIW slot (41) corresponds to one dipole (221) of the dipole array (22); and the center of each millimeter wave SIW slot (41) is aligned with the center of the corresponding dipole (221). The center of the second dielectric plate (12) and the second dielectric plate (12) overlap, and the linear polarization radiation of the millimeter wave SIW slot (41) is converted into circular polarization radiation through the dipole (221), so as to achieve circular polarization scanning performance in the millimeter wave frequency band; a metal floor (7) is arranged on the lower surface of the second dielectric plate (12), and a feeding circular hole for a microwave feeding probe (6) to pass through is etched on the metal floor (7); the microwave feeding probe (6) is connected to the microwave feeding patch (3), and an excitation signal is coupled to the staggered grid patch array (21) to excite the staggered grid patch array (21) to radiate, so as to form a patch antenna structure working in the microwave band.

2. The high frequency ratio dual circular polarization scanning antenna based on SIW slot array according to claim 1, characterized in that: The staggered grid patch array (21) comprises a plurality of square grid units arranged in a periodic array, and the line width of the outer frame of the staggered grid patch array (21) is half the line width of the inner square grid units.

3. The high frequency ratio dual circular polarization scanning antenna based on SIW slot array according to claim 2, characterized in that: The four corners of the staggered grid patch array (21) are all cut to form a micro-perturbation to achieve microwave circular polarization.

4. The high frequency ratio dual circular polarization scanning antenna based on SIW slot array according to claim 3, characterized in that: The dipole array (22) is an n×n array, each square grid unit of the staggered grid patch array (21) has a dipole (221), each dipole (221) is located on a diagonal of the square grid unit, and the center of the dipole (221) coincides with the center of the corresponding square grid unit.

5. The high frequency ratio dual circular polarization scanning antenna based on SIW slot array according to claim 4, characterized in that: The dipole array (22) and the staggered grid patch array (21) are nested with each other.

6. The high frequency ratio dual circular polarization scanning antenna based on SIW slot array according to claim 5, characterized in that: The millimeter wave SIW slot array patch (4) is an n×n slot array, which is independently fed by n millimeter wave feeding ports (42), that is, a row of slots is independently fed by one millimeter wave feeding port (42), and two adjacent millimeter wave feeding ports (42) have a phase difference and are excited at the same time to achieve linear polarization scanning performance in the millimeter wave frequency band, and then achieve circular polarization scanning performance in the millimeter wave band through polarization conversion of the dipole array (22).

7. The high frequency ratio dual circular polarization scanning antenna based on SIW slot array according to claim 6, characterized in that: The upper end of the microwave feeding probe (6) passes through the metal floor (7), the second dielectric plate (12) and the first dielectric plate (11) in sequence and is electrically connected to the microwave feeding patch (3); the microwave feeding patch (3) couples an excitation signal to the staggered grid patch array (21), thereby stimulating the patch radiation mode of the staggered grid patch array (21) and achieving radiation in the microwave frequency band.

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