A medium gain shaped horn antenna for interplanetary exploration

Abstract

The application discloses a medium-gain shaped horn antenna for interplanetary exploration, comprising a radiator assembly and a waveguide assembly, wherein the radiator assembly is fixedly connected to the top of the waveguide assembly. The radiator assembly comprises a multi-degree-of-freedom choke flange, and can realize double-frequency-band, double-circular-polarization and transmit-receive shared pattern shaping performance. The radiator assembly comprises an impedance matching ring, which realizes good impedance characteristics of a small-diameter circular waveguide horn at a low frequency band, and realizes port isolation of more than 25 dB without adding a filter. The radiator assembly and the waveguide assembly are metal structures made of aluminum alloy or magnesium alloy, and the antenna has good environmental adaptability in orbit, and has the advantages of simple structure, good rigidity, high reliability and the like.

Description

Technical Field

[0001] This invention relates to the field of microwave antenna technology, and more specifically to a medium-gain shaped horn antenna for interplanetary exploration. Background Technology

[0002] Currently, my country is conducting asteroid and comet exploration missions. These missions require X-band medium-gain transceiver dual-circularly polarized antennas for long-distance uplink and downlink telemetry and control with Earth. Due to the vast distance between space and Earth and the limitations of the space-to-ground link, the antenna must possess at least 105 watts of radio frequency continuous wave power and 420 watts of pulse identification-level micro-discharge capability. Influenced by the specific satellite orbit requirements and solar panel charging attitude of deep space exploration, the antenna needs to have specific beam pattern shaping characteristics in a specific beam angle domain. According to the frequencies allocated by the International Telecommunication Union (ITU), the X-band uplink frequency in deep space exploration is generally in the range of 7.10 GHz to 7.20 GHz, and the downlink frequency is generally in the range of 8.40 GHz to 8.50 GHz. To achieve the aforementioned shared transceiver antenna, the antenna needs to operate in both frequency bands.

[0003] Due to the specific satellite orbit requirements and solar panel charging attitude of deep space exploration, the antenna needs to possess specific beam pattern shaping characteristics in a particular beam angle domain. Specifically, it needs a gain greater than 6.0 dBi within an off-axis angle of ±40° and a gain greater than 7.0 dBi within an off-axis angle of ±35°. Simultaneously, the antenna needs to be dual-circularly polarized, operate on dual-band simultaneous transmission and reception, possess a qualification-grade micro-discharge capability of at least 105W continuous wave power and 420W pulse power, and have easily adjustable pointing tilt to meet the pointing requirements of the satellite-to-ground link. Existing antenna solutions cannot meet these specific requirements. Summary of the Invention

[0004] In view of this, the present invention provides a medium-gain shaped horn antenna for interplanetary exploration, which can well meet the antenna requirements of deep space exploration and has the advantages of simple structure and high reliability.

[0005] The specific technical solution adopted in this invention is as follows:

[0006] A medium-gain shaped horn antenna for interplanetary exploration includes: a radiator assembly and a waveguide assembly, wherein the radiator assembly is fixedly connected to the top of the waveguide assembly;

[0007] The radiator assembly includes a multi-degree-of-freedom choke flange, a circular waveguide output section, a tapered transition section, an impedance matching ring, and a circular waveguide input section, which are fixedly connected in sequence.

[0008] Furthermore, the waveguide assembly includes: a circular polarizer assembly, a dual waveguide tilt adjustment section, an impedance transformer, a right-handed output port, a left-handed output port, and an antenna reinforcing rib;

[0009] The circular polarizer assembly is fixedly connected to the top of the dual waveguide tilt adjustment section, and the bottom of the dual waveguide tilt adjustment section is fixedly connected to the impedance transformer. The right-hand output port and the left-hand output port are located on both sides of the input end of the impedance transformer, respectively. The antenna reinforcing ribs are distributed at 0°, 90°, 180° and 270° positions on the outer surface of the waveguide of the circular polarizer assembly and are integrally processed with the circular polarizer assembly.

[0010] Furthermore, the radius of the circular waveguide output segment satisfies the TE11 mode for transmitting the circular waveguide master mode in the waveguide cavity:

[0011]

[0012] Among them, f min TE11 This is the lowest operating frequency.

[0013] Furthermore, the multi-degree-of-freedom choke flange is composed of choke corrugated grooves and choke corrugated ridges arranged alternately from the inside to the outside in a concentric circle manner.

[0014] Furthermore, the radius of the tapered transition section is greater than or equal to the radius of the circular waveguide output section.

[0015] Furthermore, the number of impedance matching rings is greater than or equal to 2.

[0016] Furthermore, the circular polarizer assembly includes a septum circular polarizer and a rectangular-circular transition, wherein the septum circular polarizer is fixedly connected below the rectangular-circular transition.

[0017] Furthermore, the rectangular circle transitions to a circle with unequal side lengths of 2. n (n=2,3,4,…) polygonal waveguide structure.

[0018] Furthermore, the right-handed output port is a WR90 waveguide output port or a WR112 waveguide output port, and the left-handed output port is a WR112 waveguide output port.

[0019] Furthermore, the radiator assembly and the waveguide assembly are made of aluminum alloy or magnesium alloy.

[0020] Beneficial effects:

[0021] (1) A medium-gain shaped horn antenna for interplanetary exploration, comprising a radiator assembly and a waveguide assembly, wherein the radiator assembly is fixedly connected to the top of the waveguide assembly. The radiator assembly includes a multi-degree-of-freedom choke flange, which can achieve dual-band, dual-circular polarization, and transmit / receive shared pattern shaping performance. The radiator assembly includes an impedance matching ring, which achieves good impedance characteristics of a small-diameter circular waveguide horn in the low-frequency band, and at the same time achieves a port isolation better than 25dB without the addition of a filter.

[0022] (2) The waveguide assembly includes antenna stiffeners, which are integrated with the circular polarizer assembly, achieving good mechanical stiffness characteristics while significantly reducing weight.

[0023] (3) The waveguide assembly includes a dual waveguide tilt adjustment section, which makes it easier to adjust the antenna pointing tilt angle.

[0024] (4) The radiator assembly and waveguide assembly are made of aluminum alloy or magnesium alloy metal structure, which enables the antenna to have good environmental adaptability on the track and has the advantages of simple structure, good rigidity and high reliability. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the structure of a medium-gain shaped horn antenna according to an embodiment of the present invention;

[0026] Figure 2 This is a schematic diagram of the structure of the radiator assembly according to an embodiment of the present invention;

[0027] Figure 3 This is a schematic diagram of the structure of the radiator assembly according to an embodiment of the present invention;

[0028] Figure 4 This is a schematic diagram of the structure of a medium-gain shaped horn antenna according to an embodiment of the present invention;

[0029] Figure 5 This is a schematic diagram of the structure of a medium-gain shaped horn antenna according to an embodiment of the present invention;

[0030] Figure 6 This is a schematic diagram of the measured circular polarization gain direction effect in the left-handed 7.15GHz band according to an embodiment of the present invention;

[0031] Figure 7 This is a schematic diagram of the measured circular polarization gain direction effect in the right-hand 8.45GHz band according to an embodiment of the present invention;

[0032] Figure 8 This is a schematic diagram of the measured results of ports 1 and 2 in an embodiment of the present invention.

[0033] Among them, 1-radiator assembly, 11-circular waveguide output section, 12-multi-degree-of-freedom choke flange, 121-choke corrugated groove, 122-choke corrugated ridge, 13-tapered transition section, 14-impedance matching ring, 15-circular waveguide input section, 2-waveguide assembly, 21-circular polarizer assembly, 211-partition circular polarizer, 212-rectangular transition, 22-dual waveguide tilt adjustment section, 23-impedance transformation, 24-right-handed output port, 25-left-handed output port, 26-antenna reinforcing rib. Detailed Implementation

[0034] This invention provides a medium-gain shaped horn antenna for interplanetary exploration, comprising a radiator assembly and a waveguide assembly, with the radiator assembly fixedly connected to the top of the waveguide assembly. The radiator assembly includes a multi-degree-of-freedom choke flange, enabling dual-band, dual-circular polarization, and shared transmit / receive pattern shaping performance. The radiator assembly includes an impedance matching ring, achieving good impedance characteristics for a small-diameter circular waveguide horn in the low-frequency band, while also achieving port isolation better than 25dB without additional filters. Both the radiator assembly and the waveguide assembly are aluminum or magnesium alloy metal structures, providing excellent on-orbit environmental adaptability and offering advantages such as simple structure, high rigidity, and high reliability.

[0035] Currently, there are two main types of medium-gain antennas. The first type is a multimode horn antenna, which achieves a Gaussian beam effect and has high axial gain. The gain gradually decreases from the axial direction towards both sides of the antenna as the deviation angle increases. Within a specific angular region (±40°), the gain is generally 1.5dBi to 2.5dBi. This type of antenna cannot meet the engineering application requirements of interplanetary exploration missions.

[0036] Another approach is to implement beamforming antennas for specific needs. This involves using a dielectric radome on top of a coaxial multimode horn to achieve specific beamforming, resulting in a gain greater than 7 dBi within a ±15° beam range and a gain greater than 3.4 dBi within ±40°. However, this approach has several drawbacks: First, it can only operate within a narrowband, making it difficult to implement wideband or dual-band designs that allow for both transmit and receive. Second, the gain in the ±40° and ±35° off-axis angle regions does not meet the overall engineering requirements.

[0037] One existing beamforming antenna uses a conventional conical horn followed by a spiral wire with a specific distance and number of turns at a certain distance. Secondary radiation is generated by inducing a current on the spiral wire, which superimposes with the radiation field of the conical horn to produce a specific beamform, achieving a gain greater than 8.0 dBi within ±30°. The main problems with this antenna are that the single-wound spiral wire cannot achieve dual circular polarization, and secondly, the power capacity of spiral antennas is difficult to meet the 105-watt continuous wave requirement.

[0038] An existing beamforming antenna achieves beamforming in a specific area using a small-angle horn-shaped antenna with an axial corrugated transition section, achieving a gain greater than 10.0 dBi within a ±25° beam range. The main problem with this antenna is its bandwidth; it is only suitable for separate transmit and receive operations in a single frequency band or a narrow frequency band, and cannot achieve the dual-band transmit and receive sharing effect.

[0039] None of the above antenna solutions can solve the problem that this invention aims to address.

[0040] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0041] This invention provides a medium-gain shaped horn antenna for interplanetary exploration. Figure 1 This is a schematic diagram of the structure of a medium-gain shaped horn antenna according to an embodiment of the present invention, as shown below. Figure 1 As shown, it includes: a radiator assembly 1 and a waveguide assembly 2, with the radiator assembly 1 fixedly connected to the top of the waveguide assembly 2;

[0042] The radiator assembly 1 includes a multi-degree-of-freedom choke flange 12, a circular waveguide output section 11, a tapered transition section 13, an impedance matching ring 14, and a circular waveguide input section 15, which are fixedly connected in sequence.

[0043] In the specific implementation process, the radiator assembly 1 is fixedly connected to the top of the waveguide assembly 2 by connecting the circular waveguide input section 15 and the circular polarizer assembly 21 of the waveguide assembly 2.

[0044] In the specific implementation process, the multi-degree-of-freedom choke flange 12 is an axisymmetric rotating body structure. The multi-degree-of-freedom choke flange 12 and the circular waveguide output section 11 are coaxial in position, but the vertical position relationship is not restricted.

[0045] In one specific embodiment, the radiator assembly 1 and the waveguide assembly 2 are made of aluminum alloy or magnesium alloy.

[0046] Figure 2 This is a schematic diagram of the structure of the radiator assembly according to an embodiment of the present invention, as shown below. Figure 2 As shown, the radiator assembly includes a multi-degree-of-freedom choke flange 12, a circular waveguide output section 11, and a circular waveguide input section 15. Figure 3 This is a schematic diagram of the structure of the radiator assembly according to an embodiment of the present invention, as shown below. Figure 3 As shown, the radiator assembly includes a tapered transition section 13 and an impedance matching ring 14.

[0047] In one specific embodiment, the radius of the circular waveguide output segment 11 satisfies the waveguide cavity transmission of the circular waveguide master mode TE11:

[0048]

[0049] Among them, f min TE11 This is the lowest operating frequency.

[0050] In actual implementation, the dimensions of the circular waveguide output section 11 are determined according to the radiation pattern shaping requirements. Generally, when a wider beamwidth is required, this diameter should be kept as small as possible, but it should be ensured that the waveguide cavity can transmit the circular waveguide master mode TE. 11 The mode, i.e., the radius of the circular waveguide output segment 11, should satisfy the above formula, where f min TE11 To correspond to the lowest operating frequency, the radius is selected as 13.5mm in this embodiment.

[0051] In one specific embodiment, the multi-degree-of-freedom choke flange 12 is composed of choke corrugated grooves 121 and choke corrugated ridges 122 arranged alternately from the inside to the outside in a concentric circle manner.

[0052] In the specific implementation process, the multi-degree-of-freedom choke flange 12 is a corrugated structure distributed in multiple layers from the inside to the outside. Each corrugation cycle consists of corrugated grooves and corrugated ridges. The corrugated grooves and corrugated ridges are continuously distributed between adjacent corrugation cycles. The choke corrugated grooves 121 and choke corrugated ridges 122 are arranged in a concentric circle and alternately arranged from the inside to the outside.

[0053] In actual implementation, the number, height, depth, and width of the undulating corrugated grooves 121 and undulating corrugated ridges 122 are specifically determined by the radiation pattern characteristic optimization design, such as... Figure 3 As shown, the height of the eccentric ridge 122 should gradually increase from the inside out, that is, the height of the (n+1)th eccentric ridge should not be less than the height of the nth eccentric ridge. In this embodiment, there are 6 eccentric ridges 122 and 5 eccentric grooves 121. In this embodiment, the thickness of the eccentric ridge 122 from the inside out is 3.67mm, 6.56mm, 4.36mm, 4.65mm, 3.80mm, and 1.0mm respectively. The width of the eccentric groove 121 from the inside out is 16.2mm, 7.65mm, 7.37mm, 9.98mm, and 11.7mm respectively.

[0054] In one specific embodiment, the radius of the tapered transition section 13 is greater than or equal to the radius of the circular waveguide output section 11.

[0055] In actual implementation, the length and diameter of the tapered transition section 13 are determined based on the impedance characteristics and radiation pattern characteristics. The radius of the tapered transition section 13 should not be less than the radius of the circular waveguide output section 11. In this embodiment, the radius of the tapered transition section 13 is selected as 14.2 mm, and the length is 2 mm.

[0056] In one specific embodiment, the number of impedance matching rings 14 is greater than or equal to 2.

[0057] In the actual implementation, the impedance matching rings are located between the input waveguide section 15 and the tapered transition section 13. The specific size and location of each impedance matching ring need to be determined based on numerical optimization analysis. There are no restrictions on how they are distributed, and they do not necessarily need to be uniformly distributed.

[0058] In actual implementation, the number and size of the impedance matching rings 14 are optimized based on the overall impedance characteristics and port isolation characteristics of the antenna. Generally, the number should be no less than two; in this embodiment, there are two. The impedance matching rings 14 have a thickness of 1.8 mm and a length of 1.1 mm. Figure 3 As shown, the impedance matching ring 14 is distributed between the circular waveguide input section 15 and the tapered transition section 13.

[0059] In one specific embodiment, Figure 4 This is a schematic diagram of the structure of a medium-gain shaped horn antenna according to an embodiment of the present invention. Figure 5 This is a schematic diagram of the structure of a medium-gain shaped horn antenna according to an embodiment of the present invention, as shown below. Figure 4 As shown, waveguide assembly 2 includes: a circular polarizer assembly 21, a dual waveguide tilt adjustment section 22, an impedance transformer 23, a right-handed output port 24, and as shown in the figure. Figure 5 The left-hand output port 25 and antenna reinforcing rib 26 are shown.

[0060] The circular polarizer assembly 21 is fixedly connected to the top of the dual waveguide tilt adjustment section 22, and the bottom of the dual waveguide tilt adjustment section 22 is fixedly connected to the impedance transformer 23. The right-hand output port 24 and the left-hand output port 25 are located on both sides of the input end of the impedance transformer 23, respectively. The antenna reinforcing ribs 26 are distributed at 0°, 90°, 180° and 270° positions on the outer surface of the waveguide of the circular polarizer assembly 21, and are integrally processed with the circular polarizer assembly 21.

[0061] In the specific implementation process, the bottom of the dual waveguide tilt adjustment section 22 is fixedly connected to the impedance transformer 23 at a fixed tilt angle. The impedance transformer 23 is a dual-channel element, with the right-hand circular output port 24 and the left-hand circular output port 25 located on both sides of the input end of the impedance transformer 23, respectively, for transmitting left-hand circularly polarized and right-hand circularly polarized waves.

[0062] In the specific implementation process, the antenna reinforcing ribs 26 are distributed on the outer surface of the waveguide assembly 2. The outer surface of the waveguide assembly is actually a tetrahedron, with a rectangular body at the center of each face. There are a total of four rectangular bodies on the four faces, which are four ribs.

[0063] In actual implementation, such as Figure 4As shown, the dual waveguide tilt adjustment section 22 mainly realizes the function of arbitrarily adjusting the beam direction. The bottom of the dual waveguide tilt adjustment section 22 is positioned and installed at the top of the impedance transformer 23 through mounting screws and mounting pins. In this embodiment, the tilt adjustment angle is 37.5°. The impedance transformer 23 realizes the function of converting the standard waveguide interface to a non-standard interface. The antenna reinforcing rib 26 is mainly used to achieve better stiffness and mechanical characteristics of the antenna while reducing weight. This dimension needs to be optimized and determined according to the mechanical characteristics.

[0064] In one specific embodiment, the circular polarizer assembly 21 includes a partition circular polarizer 211 and a rectangular-circular transition 212, with the partition circular polarizer 211 fixedly connected below the rectangular-circular transition 212.

[0065] In actual implementation, the circular polarizer 211 is a conventional septum circular polarizer, and the rectangular-circular transition 212 realizes the conversion from square waveguide to circular waveguide.

[0066] In one specific embodiment, the rectangular-circular transition 212 has two sides of unequal length. n (n = 2, 3, 4, ...) waveguide structure. For example, it can be a hexagonal waveguide structure with unequal side lengths.

[0067] In one specific embodiment, the right-hand circular output port 24 is a WR90 waveguide output port or a WR112 waveguide output port, capable of transmitting 8.3GHz to 8.6GHz right-hand circularly polarized signals; the left-hand circular output port 25 is a WR112 waveguide output port, capable of transmitting 7.0GHz to 7.3GHz left-hand circularly polarized signals.

[0068] To more clearly demonstrate the effects of the present invention, actual measurements were performed using the medium-gain shaped horn antenna provided in the above embodiments of the present invention. Figure 6 This is a schematic diagram illustrating the measured directional effect of circular polarization gain in the 7.15GHz band of the left-hand circular polarization according to an embodiment of the present invention. Figure 6 As shown, the antenna has a gain of not less than 7.0 dBi in the ±35° angular range and a gain of not less than 6.0 dBi in the ±40° angular range.

[0069] Figure 7 This is a schematic diagram illustrating the measured directional effect of circular polarization gain in the right-hand 8.45GHz band according to an embodiment of the present invention. Figure 7 As shown, the antenna gain is no less than 7.5 dBi in the ±35° angular range; and the antenna gain is no less than 6.2 dBi in the ±40° angular range.

[0070] Figure 8 This is a schematic diagram illustrating the measured results of ports 1 and 2 in an embodiment of the present invention, as shown below. Figure 8As shown, the VSWR diagram and the port isolation diagram between port 1 and port 2 show an effect greater than 26.16dB within the operating frequency band.

[0071] The above embodiments of the present invention ensure that the antenna operates within the operating frequency range of 7.1GHz to 7.2GHz and 8.4GHz to 8.45GHz. The antenna achieves dual-band operation, dual circular polarization, beamforming, and good port isolation. Testing shows that the off-axis gain at ±40° is not less than 6.2dBi, the off-axis gain at ±35° is not less than 7.3dBi, and the port isolation is not less than 25dB. The antenna passed the qualification-level random vibration dynamics test conditions shown in Table 1. The antenna adopts an all-metal structure, exhibits excellent environmental adaptability in orbit, and has advantages such as simple structure, good rigidity, and high reliability.

[0072] Table 1

[0073]

[0074] It also has the advantages of simple structure, good rigidity and high reliability. The antenna passed the qualification level mechanical environment conditions shown in Table 1 and can be used for future interplanetary deep space exploration missions such as the exploration of asteroids, comets, the Jupiter system, Mars, Venus, the Sun and its boundaries.

[0075] In summary, this invention provides a spaceborne, non-adjustable, medium-gain shaped antenna suitable for interplanetary exploration. By utilizing a circular waveguide horn antenna loaded with a multi-degree-of-freedom choke flange, it achieves dual-band, dual-circular polarization, port isolation of not less than 22dB, continuous wave power of not less than 105W, and identification-level micro-discharge and transceiver sharing of 420W pulse, and the antenna pointing and tilt angle is easily adjustable. It has the advantages of simple structure, good rigidity, and high reliability.

[0076] The specific embodiments described above only illustrate the design principles of the present invention. The shapes and names of the components in this description may differ and are not limited. Therefore, those skilled in the art can modify or make equivalent substitutions to the technical solutions described in the foregoing embodiments; and such modifications and substitutions do not depart from the inventive spirit and technical solutions of the present invention, and should all fall within the protection scope of the present invention.

Claims

1. A medium-gain shaped horn antenna for interplanetary exploration, characterized in that, include: A radiator assembly (1) and a waveguide assembly (2), wherein the radiator assembly (1) is fixedly connected to the top of the waveguide assembly (2); The radiator assembly (1) includes a multi-degree-of-freedom choke flange (12), a circular waveguide output section (11), a tapered transition section (13), an impedance matching ring (14), and a circular waveguide input section (15) that are fixedly connected in sequence; the waveguide assembly (2) includes a circular polarizer assembly (21), a dual waveguide tilt adjustment section (22), an impedance transformer (23), a right-hand circular output port (24), a left-hand circular output port (25), and an antenna reinforcing rib (26). The circular polarizer assembly (21) is fixedly connected to the top of the dual waveguide tilt adjustment section (22), and the bottom of the dual waveguide tilt adjustment section (22) is fixedly connected to the impedance transformer (23). The right-hand output port (24) and the left-hand output port (25) are located on both sides of the input end of the impedance transformer (23). The antenna reinforcing ribs (26) are distributed at 0°, 90°, 180° and 270° positions on the outer surface of the waveguide of the circular polarizer assembly (21) and are integrally processed with the circular polarizer assembly (21).

2. The medium-gain shaped horn antenna as described in claim 1, characterized in that, The radius of the circular waveguide output section (11) satisfies the TE11 mode of the waveguide cavity transmission circular waveguide master mode: in, This is the lowest operating frequency.

3. The medium-gain shaped horn antenna as described in claim 1, characterized in that, The multi-degree-of-freedom choke flange (12) is composed of choke corrugated grooves (121) and choke corrugated ridges (122) arranged alternately from the inside to the outside in a concentric circle manner.

4. The medium-gain shaped horn antenna as described in claim 1, characterized in that, The radius of the tapered transition section (13) is greater than or equal to the radius of the circular waveguide output section (11).

5. The medium-gain shaped horn antenna as described in claim 1, characterized in that, The number of impedance matching rings (14) is greater than or equal to 2.

6. The medium-gain shaped horn antenna as described in claim 1, characterized in that, The circular polarizer assembly (21) includes a septum circular polarizer (211) and a rectangular-circular transition (212), wherein the septum circular polarizer (211) is fixedly connected below the rectangular-circular transition (212).

7. The medium-gain shaped horn antenna as described in claim 6, characterized in that, The rectangular-circular transition (212) consists of 2 sides with unequal lengths. n (n=2,3,4,…) polygonal waveguide structure.

8. The medium-gain shaped horn antenna as described in claim 1, characterized in that, The right-hand output port (24) is a WR90 waveguide output port or a WR112 waveguide output port, and the left-hand output port (25) is a WR112 waveguide output port.

9. The medium-gain shaped horn antenna as described in claim 1, characterized in that, The radiator assembly (1) and the waveguide assembly (2) are made of aluminum alloy or magnesium alloy.

Images