Small-frequency-ratio broadband dual-frequency dual-circularly-polarized coaxial common-caliber horn antenna unit

Abstract

The invention relates to a small-frequency-ratio broadband dual-frequency dual-circularly-polarized coaxial common-caliber horn antenna unit, and belongs to the field of electronic science and technology. Comprising a low-frequency horn wall, a high-frequency horn wall, a low-frequency feed ridge, a low-frequency dual-circular-polarization synthesis network, a coaxial conductor, a high-frequency dual-circular-polarization synthesis network and a high-frequency feed probe, the low-frequency horn wall is arranged on the outer side of the high-frequency horn wall to jointly form a horn antenna side wall, the low-frequency feed ridge is arranged between the low-frequency horn wall and the high-frequency horn wall and is connected with the low-frequency horn wall, and the low-frequency band dual-circular polarization synthesis network is arranged below the low-frequency horn wall and is connected with the low-frequency feed ridge through a coaxial conductor arranged in the bottom of the low-frequency horn wall. The high-frequency band dual-circular polarization synthesis network is arranged below the high-frequency band horn wall and is connected with the high-frequency band horn wall, and the high-frequency feed probe is arranged on the side surface of the high-frequency band dual-circular polarization synthesis network. Through the addition of the low-frequency-band feed ridge, the bandwidth of low-frequency-band work is effectively improved, and the small-frequency-ratio broadband design of the dual-frequency-band common-caliber horn is realized.

Description

Technical Field

[0001] The invention belongs to the field of electronic science and technology, and particularly relates to a small frequency ratio broadband dual-frequency dual-circular polarization coaxial common aperture horn antenna unit. Background Art

[0002] Array antennas can achieve a variety of different beams by changing the feeding phase and amplitude of the unit and are widely used. However, traditional arrays are often limited by the fact that the antenna unit can only work in a single frequency band. When multi-band operation is required, multiple array surfaces are required, which greatly reduces the aperture utilization of the antenna array surface. A common aperture antenna array refers to an antenna array that places multiple antennas with different frequency bands and functions in the same radiation aperture surface, and through reasonable design, it can work independently without interfering with each other. The common aperture antenna can not only realize the antenna radiation of multiple frequency bands within a limited radiation surface, but also independently adjust the radiation performance of antenna arrays of different frequency bands. Antennas with multiple frequency bands and multiple polarizations are integrated into the same aperture, which can maximize the aperture utilization and improve the aperture reuse efficiency. It is of key significance to reduce the cost of antenna systems and payload platforms and improve the system's multi-band and multi-functional integration capabilities. Horn antennas have high phase center stability and are widely used in the field of satellite measurement and control. In order to achieve multi-band design, horn antennas can choose common aperture or common aperture. The common aperture type has an antenna aperture related to the low-frequency cutoff frequency, so it is impossible to suppress the grating lobe when forming an array. The common aperture type dual-band horn antenna will have a smaller aperture and is more conducive to array formation. However, the common aperture horn antenna fed by the traditional coaxial probe can only achieve a frequency ratio of about 5 times the frequency when the bandwidth requirement is 30%-40%. Therefore, it is of practical significance to propose a small frequency ratio broadband dual-frequency dual circularly polarized coaxial common aperture horn antenna. Summary of the invention

[0003] The technical problems to be solved by the present invention are:

[0004] In order to avoid the deficiencies of the prior art, the present invention provides a small frequency ratio broadband dual-frequency dual-circular polarization coaxial common aperture horn antenna unit, which is used to solve the small frequency ratio design problem of the common aperture dual-band horn antenna.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0006] A small frequency ratio broadband dual-frequency dual circularly polarized coaxial common aperture horn antenna unit, characterized in that it comprises: a low frequency horn wall, a high frequency horn wall, a low frequency feeding ridge, a low frequency dual circularly polarized synthesis network, a coaxial sub, a high frequency dual circularly polarized synthesis network and a high frequency feeding probe;

[0007] The low-frequency speaker wall is placed on the outside of the high-frequency speaker wall, and together they form the side wall of the speaker antenna;

[0008] The low-frequency feeding ridge is placed between the low-frequency speaker wall and the high-frequency speaker wall, and is connected to the low-frequency speaker wall;

[0009] The low-frequency dual circular polarization synthesis network is placed below the low-frequency speaker wall and connected to the low-frequency feeding ridge via a coaxial sub-coil placed inside the bottom of the low-frequency speaker wall;

[0010] The high-frequency band dual circular polarization synthesis network is placed below the high-frequency band speaker wall and connected to the high-frequency band speaker wall;

[0011] The high-frequency feeding probe is placed on the side of the high-frequency band dual circular polarization synthesis network.

[0012] A further technical solution of the present invention is as follows: the low-frequency speaker wall is divided into two parts: a bottom surface and a side wall, wherein the upper half of the side wall gradually opens.

[0013] A further technical solution of the present invention is as follows: the high-frequency speaker wall is only composed of side walls and does not include a bottom surface, wherein the side walls are divided into a lower half with a constant diameter and an upper half that gradually opens.

[0014] A further technical solution of the present invention is as follows: the low-frequency feeding ridges include four, which are evenly distributed around the central axis of the low-frequency speaker wall; the upper half is connected to the side wall of the low-frequency speaker wall, the lower half is an impedance matching section, and there is a gap between the lower half and the side wall of the low-frequency speaker wall.

[0015] A further technical solution of the present invention is as follows: the low-frequency band dual circular polarization synthesis network is in the shape of a circular ring structure, which is a multi-layer dielectric substrate with 4 copper surfaces, and is pressed from multiple dielectric substrates with printed circuits. After passing through the low-frequency band dual circular polarization synthesis network, the radio frequency signal is divided into four signals with equal amplitude and sequential phases.

[0016] A further technical solution of the present invention is as follows: a high-frequency band dual circular polarization synthesis network is divided into two parts, one part is a transition section that transmits the radio frequency signal from the circular waveguide section to the rectangular section; the other part is a rectangular waveguide with a side length of 5, and the center of the rectangular waveguide is a 5-step step transformation section to realize the formation of circular polarization of the high-frequency signal.

[0017] A further technical solution of the present invention includes a medium guide rod, wherein the medium guide rod is located at the top of the high-frequency speaker wall.

[0018] A further technical solution of the present invention is as follows: the dielectric guide rod is divided into two parts, the upper part is a radiation section, which is formed into two gradually tapering cones, and the lower part is a 4th-order gradually tapering impedance matching section.

[0019] The beneficial effects of the present invention are:

[0020] The invention provides a small frequency ratio broadband dual-frequency dual circularly polarized coaxial common aperture horn antenna unit. On the basis of the dual-band common aperture horn antenna, the low-frequency band working bandwidth is effectively improved by adding a low-frequency band feeding ridge, and the small frequency ratio broadband design of the dual-band common aperture horn is realized. On this basis, the integrated design of the dual circularly polarized feeding network and the antenna is realized. It has the advantages of simple structure, small lateral size, stable and reliable electrical performance, and easy mass production. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The drawings are only for the purpose of illustrating particular embodiments and are not to be considered limiting of the present invention. Like reference symbols denote like components throughout the drawings.

[0022] Figure 1 is an overall structural diagram of an antenna according to an embodiment of the present invention;

[0023] Figure 2 An exploded view of an antenna according to an embodiment of the present invention;

[0024] Figure 3 It is a schematic diagram of a low-frequency speaker wall of an antenna according to an embodiment of the present invention;

[0025] Figure 4 A schematic diagram of a high-frequency speaker wall of an antenna according to an embodiment of the present invention;

[0026] Figure 5 A schematic diagram of a low-frequency dual-polarization synthesis network of an antenna according to an embodiment of the present invention;

[0027] Figure 6 A schematic diagram of a coaxial sub-device of an antenna according to an embodiment of the present invention;

[0028] Figure 7 A schematic diagram of a high frequency dual circular polarization synthesis network of an antenna according to an embodiment of the present invention;

[0029] Figure 8 Schematic diagram of a dielectric guide rod of an antenna according to an embodiment of the present invention;

[0030] Fig. 9 A schematic diagram of a high-frequency feeding probe of an antenna according to an embodiment of the present invention;

[0031] Fig.10 The voltage standing wave ratio of the dual circular polarization port in the low frequency band of the antenna according to the embodiment of the present invention;

[0032] Fig.11 This is the 1.7 GHz radiation pattern of the antenna according to the embodiment of the present invention;

[0033] Fig.12 This is the 2.4 GHz radiation pattern of the antenna according to the embodiment of the present invention;

[0034] Fig.13The voltage standing wave ratio of the dual circular polarization port in the high frequency band of the antenna according to the embodiment of the present invention;

[0035] Fig.14 This is the 5.1 GHz radiation pattern of the antenna according to the embodiment of the present invention;

[0036] Fig.15 This is the 6.0 GHz radiation pattern of the antenna according to the embodiment of the present invention.

[0037] In the figure:

[0038] 1- low frequency speaker wall, 2- high frequency speaker wall, 3- low frequency feeding ridge, 4- low frequency dual circular polarization synthesis network, 5- coaxial sub, 6- high frequency dual circular polarization synthesis network, 7- dielectric guide rod, 8- high frequency feeding probe. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0040] refer to Figure 1-Figure 2 , a small frequency ratio broadband dual-frequency dual circular polarization coaxial common aperture horn antenna unit provided by an embodiment of the present invention, which includes eight parts: a low-frequency horn wall 1, a high-frequency horn wall 2, a low-frequency feeding ridge 3, a low-frequency dual circular polarization synthesis network 4, a coaxial sub 5, a high-frequency dual circular polarization synthesis network 6, a dielectric guide rod 7 and a high-frequency feeding probe 8. The low-frequency horn wall 1 is placed on the outside of the high-frequency horn wall 2, and together constitutes the side wall of the horn antenna, the low-frequency feeding ridge 3 is placed between the low-frequency horn wall 1 and the high-frequency horn wall 2, and is connected to the low-frequency horn wall 1, the low-frequency dual circular polarization synthesis network 4 is placed below the low-frequency horn wall 1, and is connected to the low-frequency feeding ridge 3 through the coaxial sub 5 placed inside the bottom of the low-frequency horn wall 1. The high-frequency dual circular polarization synthesis network 6 is placed below the high-frequency horn wall 2, and is connected to the high-frequency horn wall 2, the high-frequency feeding probe 8 is placed on the side of the high-frequency dual circular polarization synthesis network 6, and the dielectric guide rod 7 is placed on the top of the high-frequency horn wall 2.

[0041] The following is a detailed description of each component:

[0042] like Figure 3 As shown, it is a schematic diagram of the structure of the low-frequency speaker wall 1. The low-frequency speaker wall 1 is made of aluminum and can be divided into two parts: a bottom surface and a side wall. The lower part of the side wall is 50 mm high and 96 mm in diameter, while the upper part of the side wall gradually opens to a height of 52 mm and gradually opens to 114 mm.

[0043] like Figure 3 As shown, the low-frequency feed ridge 3 is located on the inner side of the side wall of the low-frequency speaker wall 1, including 4 ridges, which are evenly distributed around the central axis of the low-frequency speaker wall 1. Each low-frequency feed ridge 3 is divided into two sections, wherein the upper section is connected to the side wall of the low-frequency speaker wall 1, and the lower section is an impedance matching section. There is a gap of 5mm between the lower section and the side wall of the low-frequency speaker wall 1, the height of the lower section is 30.5mm, and the height of the upper section is 63.4mm. There is a gap of 1mm between the bottom of the low-frequency feed ridge 3 and the bottom surface of the low-frequency speaker wall 1.

[0044] like Figure 4 The figure shows the structure of the high-frequency speaker wall 2. The high-frequency speaker wall 2 is similar to the low-frequency speaker wall 1 and is made of aluminum. The high-frequency speaker wall 2 is located inside the low-frequency speaker wall 1 and is divided into a lower half with a constant diameter and an upper half that gradually opens. However, unlike the low-frequency speaker wall 1, it is only composed of side walls and does not include a bottom surface. The diameter of the lower half is 38 mm and the height is 93 mm. The diameter of the upper half gradually opens to 44 mm and the height is 10 mm.

[0045] like Figure 5 As shown, it is a schematic diagram of the structure of the low-frequency dual circular polarization synthesis network 4. The low-frequency dual circular polarization synthesis network 4 is placed below the bottom surface of the low-frequency speaker wall 1. It is in the shape of a ring structure. The whole is a 4-layer copper surface multi-layer dielectric substrate with a dielectric constant of 3.55, which is pressed by multiple dielectric substrates with printed circuits. After passing through, the RF signal is divided into four signals with equal amplitude and sequential phase.

[0046] like Figure 6 As shown, it is a schematic diagram of the structure of the coaxial sub 5, and its structure can be divided into three parts, a core wire, an insulating layer and an outer conductor. The core wire is a cylinder, and the insulating layer and the outer conductor are a circular cylindrical structure. The coaxial sub 5 is placed inside the bottom plate of the low-frequency speaker wall 1 and is embedded in the bottom plate as a whole. The thickness of the core wire of the coaxial sub 5 is 2mm, and its upper part is connected to the low-frequency feeding ridge 3, and the lower part is connected to the low-frequency dual circular polarization synthesis network 4. The outer diameter of the insulating layer is 6mm, and the height of the insulating layer and the outer conductor is consistent with the thickness of its bottom plate.

[0047] like Figure 7 As shown, it is a schematic diagram of the structure of the high-frequency dual circular polarization synthesis network 6. The high-frequency dual circular polarization synthesis network 6 is placed below the high-frequency speaker wall 2 and can be divided into two parts. The first is a transition section that transmits the RF signal from the circular waveguide section to the rectangular section. Its height is 28.5mm, and the bottom is a rectangular waveguide with a side length of 34mm, and the center is a 5-step ladder transformation section to achieve the formation of circular polarization of the high-frequency signal.

[0048] like Figure 8As shown in the figure, it is a schematic diagram of the structure of the dielectric guide rod 7. The dielectric guide rod 7 is placed above the high-frequency speaker wall 2 and can be divided into two parts. The upper part is the radiation section, which is formed into two gradually tapering cones. The lengths of the two sections are 18mm and 220mm respectively, and the diameter gradually changes from 38mm to 24mm and then to 16mm. The lower section is a 4-order gradually tapering impedance matching section. It can realize the gathering effect of electromagnetic waves and improve their directivity.

[0049] like Fig. 9 As shown, it is a schematic diagram of the structure of the high-frequency feeding probe 8. The high-frequency feeding probe 8 is placed inside the side wall of the high-frequency dual circular polarization synthesis network 6. Its core wire extends into the interior of the high-frequency dual circular polarization synthesis network 6 and is divided into two sections with a total length of 9.3 mm, a distal length of 1.3 mm, a diameter of 2.4 mm, and a proximal length of 8 mm and a diameter of 1 mm.

[0050] The results of the technical embodiments of the present invention are further illustrated by simulation:

[0051] 1. Simulation content:

[0052] Please refer to Figure 10-15 The voltage standing wave ratio, radiation pattern and gain characteristics of the antenna in the above technical embodiment were simulated and calculated using simulation software.

[0053] 2. Simulation results:

[0054] Fig.10 The characteristic of the voltage standing wave ratio changing with the operating frequency obtained by simulating the low frequency band of the antenna in the technical embodiment is as follows: Fig.10 It can be seen that the low frequency band of the antenna of the embodiment of the present invention works in the L and S frequency bands, achieving a relative bandwidth of 34%. Fig.13 It can be seen that the high frequency band of the antenna in the embodiment of the present invention works in the C band, achieving a relative bandwidth of 16%.

[0055] from Figure 11-Figure 12 This is a low-frequency related directional diagram of the antenna of the embodiment of the antenna of the present invention. The antenna of the embodiment of the antenna of the present invention has a gain of more than 7dB in the L and S (ie, low frequency band) working frequency bands.

[0056] from Figure 14-15 This is a high frequency related radiation diagram of the antenna of the embodiment of the antenna of the present invention. The antenna of the embodiment of the antenna of the present invention has a gain of more than 15dB in the working frequency band C (ie, high frequency band).

[0057] The simulation results show that the loading of the low-frequency band feeding ridge can effectively realize the small frequency ratio operation of the dual-band common-aperture horn antenna, and at the same time has a smaller lateral size to meet the array requirements. The antenna of the technical embodiment of the present invention can meet the requirements of miniaturization of the lateral size and small frequency ratio design of the dual-band common-aperture antenna.

[0058] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should be included in the protection scope of the present invention.

Claims

1. A small frequency ratio broadband dual-frequency dual-circular polarization coaxial common aperture horn antenna unit, characterized in that: include: A low-frequency speaker wall (1), a high-frequency speaker wall (2), a low-frequency feeding ridge (3), a low-frequency dual circular polarization synthesis network (4), a coaxial sub-element (5), a high-frequency dual circular polarization synthesis network (6), and a high-frequency feeding probe (8); The low-frequency speaker wall (1) is placed on the outside of the high-frequency speaker wall (2), and together they form a side wall of the speaker antenna; The low-frequency feeding ridge (3) is placed between the low-frequency speaker wall (1) and the high-frequency speaker wall (2), and is connected to the low-frequency speaker wall (1); The low-frequency dual circular polarization synthesis network (4) is placed below the low-frequency speaker wall (1) and is connected to the low-frequency feeding ridge (3) via a coaxial sub-axis (5) placed inside the bottom of the low-frequency speaker wall (1); The high-frequency band dual circular polarization synthesis network (6) is placed below the high-frequency band speaker wall (2) and is connected to the high-frequency band speaker wall (2); The high-frequency feeding probe (8) is placed on the side of the high-frequency band dual circular polarization synthesis network (6).

2. According to claim 1, a small frequency ratio broadband dual-frequency dual-circular polarization coaxial common aperture horn antenna unit is characterized in that: The low-frequency speaker wall (1) is divided into two parts: a bottom surface and a side wall, wherein the upper half of the side wall gradually opens.

3. According to claim 1, a small frequency ratio broadband dual-frequency dual-circular polarization coaxial common aperture horn antenna unit is characterized in that: The high-frequency speaker wall (2) is composed only of side walls and does not include a bottom surface, wherein the side walls are divided into a lower half section with a constant diameter and an upper half section that gradually opens.

4. According to claim 1, a small frequency ratio broadband dual-frequency dual-circular polarization coaxial common aperture horn antenna unit is characterized in that: The low-frequency feeding ridges (3) include four ridges evenly distributed around the central axis of the low-frequency speaker wall (1); the upper half is connected to the side wall of the low-frequency speaker wall (1), and the lower half is an impedance matching section, with a gap between the lower half and the side wall of the low-frequency speaker wall (1).

5. According to claim 1, a small frequency ratio broadband dual-frequency dual-circular polarization coaxial common aperture horn antenna unit, characterized in that: The low-frequency dual circular polarization synthesis network (4) is in the shape of a circular ring structure and is a multi-layer dielectric substrate with four copper surfaces, which is formed by pressing a plurality of dielectric substrates with printed circuits. After passing through the low-frequency dual circular polarization synthesis network (4), the radio frequency signal is divided into four signals with equal amplitude and sequential phases.

6. The small frequency ratio broadband dual-frequency dual-circular polarization coaxial common aperture horn antenna unit according to claim 1, characterized in that: The high-frequency band dual circular polarization synthesis network (6) is divided into two parts, one part is a transition section for transmitting the radio frequency signal from the circular waveguide section to the rectangular section; the other part is a rectangular waveguide with a side length of 5 and a 5-step step transformation section at the center of the rectangular waveguide to realize the formation of circular polarization of the high-frequency signal.

7. The small frequency ratio broadband dual-frequency dual-circular polarization coaxial common aperture horn antenna unit according to claim 1, characterized in that: It also comprises a medium guide rod (7), wherein the medium guide rod (7) is located at the top of the high-frequency speaker wall (2).

8. The small frequency ratio broadband dual-frequency dual-circular polarization coaxial common aperture horn antenna unit according to claim 8, characterized in that: The dielectric guide rod (7) is divided into two parts, the upper part is a radiation section, which is formed into two gradually tapering cones, and the lower part is a 4th-order gradually tapering impedance matching section.

Images