An adaptive pointing antenna applicable to micro remote sensing satellite data transmission

Abstract

The utility model discloses a kind of adaptive pointing antennas applicable to micro remote sensing satellite data transmission, including slot waveguide array, four coupling feed waveguides, four waveguide phase shifters and four waveguide directional couplers, wherein, slot waveguide array has 2n×2n waveguide wide edge transverse slot, is divided into four sub-modules, each sub-module has n×n waveguide wide edge transverse slot;Each coupling feed waveguide is connected to one in four sub-modules;Four waveguide directional couplers are interconnected to form cross coupling structure, cross coupling structure includes four ports;The first end of each waveguide phase shifter is respectively connected to corresponding waveguide directional coupler, the second end of each waveguide phase shifter is respectively connected to corresponding coupling feed waveguide.The adaptive pointing antenna of the utility model is passive flat plate architecture, can automatically measure out pointing offset, and light in weight, small in size, applicable to micro remote sensing satellite platform.

Description

Technical Field

[0001] This utility model belongs to the field of remote sensing satellite communication antenna design technology, specifically relating to an adaptive pointing antenna that can be applied to the data transmission of small remote sensing satellites. Background Technology

[0002] During remote sensing satellite data transmission, to ensure transmission quality, the data transmission antenna of the remote sensing satellite needs to be aligned with the receiving antenna of the ground station in real time. To address this issue, phased array antennas or antennas with servo systems are mostly used in engineering to achieve real-time tracking. However, phased array antennas are heavy, consume a lot of power, and are expensive, while antennas with servo systems are large, heavy, and consume a lot of power, neither of which is suitable for use on small remote sensing satellite platforms.

[0003] Miniature remote sensing satellites typically use passive flat panel antennas for data transmission. These antennas are small, lightweight, and consume little power, making them ideal for miniature remote sensing satellites. However, these passive flat panel antennas cannot automatically adjust their pointing angle; the antenna pointing angle needs to be adjusted by changing the satellite's attitude. Furthermore, due to limitations in size, weight, and power consumption, miniature remote sensing satellites usually do not have beacon transmitters. Therefore, antenna pointing angle adjustment is an open-loop control process, lacking feedback signals. This is a unique characteristic of miniature remote sensing satellites. Because of the lack of feedback signals, antenna pointing angle deviation cannot be automatically measured. The satellite can only adjust its attitude based on the calculation results of the pointing angle formula, and the effect of the adjustment cannot be directly evaluated. Utility Model Content

[0004] To address the aforementioned problems in the existing technology, this invention provides an adaptive pointing antenna applicable to data transmission from small remote sensing satellites. The technical problem to be solved by this invention is achieved through the following technical solution: This invention provides an adaptive pointing antenna applicable to data transmission from small remote sensing satellites, comprising a slotted waveguide array, four coupled feed waveguides, four waveguide phase shifters, and four waveguide directional couplers, wherein... The slotted waveguide array has 2n×2n transverse slots along the wide side of the waveguide, and is divided into four sub-modules. Each sub-module has n×n transverse slots along the wide side of the waveguide, where n is an integer greater than or equal to 2. Each of the coupled feed waveguides is connected to one of the four sub-modules for independent energy coupling of the current sub-module; The four waveguide directional couplers are interconnected to form a cross-shaped coupling structure, which includes four ports. The first end of each waveguide phase shifter is connected to the corresponding waveguide directional coupler, and the second end of each waveguide phase shifter is connected to the corresponding coupled feed waveguide.

[0005] In one embodiment of the present invention, each of the waveguide wide-side transverse slots has the same length and width, and the length directions of each waveguide wide-side transverse slot are parallel.

[0006] In one embodiment of this utility model, four coupled feed waveguides are arranged in parallel, and each coupled feed waveguide has n first coupling slots on its upper surface.

[0007] In one embodiment of this utility model, the length direction of the coupled feed waveguide is perpendicular to the length direction of the transverse slot on the wide side of the waveguide.

[0008] In one embodiment of the present invention, each sub-module of the slot waveguide array has n second coupling slots on its lower surface, and the second coupling slots coincide with the vertical projection of the first coupling slot on the corresponding coupled feed waveguide.

[0009] In one embodiment of the present invention, the first end of each of the coupled feed waveguides is short-circuited, and the second end includes a connection port bent toward the waveguide phase shifter, and is connected to one of the four waveguide phase shifters through the connection port.

[0010] In one embodiment of this utility model, the four waveguide phase shifters include a first waveguide phase shifter, a second waveguide phase shifter, a third waveguide phase shifter, and a fourth waveguide phase shifter, wherein, The first waveguide phase shifter is a reference phase waveguide phase shifter, the second waveguide phase shifter is a λ / 4 phase waveguide phase shifter, the third waveguide phase shifter is a λ / 2 phase waveguide phase shifter, and the fourth waveguide phase shifter is a λ / 4 phase waveguide phase shifter.

[0011] In one embodiment of this utility model, the four waveguide directional couplers are interconnected to form a cross-shaped coupling structure, which includes a first port, a second port, a third port, and a fourth port. The first port is the azimuth port, the second port is the azimuth difference port, and the third and fourth ports are connected to the load.

[0012] In one embodiment of this utility model, the four waveguide directional couplers are centrally symmetrically distributed, with a cross-shaped through hole formed in the center.

[0013] Compared with the prior art, the beneficial effects of this utility model are as follows: This invention provides an adaptive pointing antenna applicable to data transmission in small remote sensing satellites. The antenna features a passive planar structure and can automatically measure the pointing offset, which serves as an input parameter for satellite attitude adjustment. It can also evaluate the accuracy of the adjusted antenna pointing angle. Compared to antennas with servo systems, it is lighter and smaller; compared to phased array antennas, it has lower power consumption and lower cost, making it ideal for use on small remote sensing satellite platforms.

[0014] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0015] Figure 1 This is a structural breakdown diagram of an adaptive pointing antenna applicable to data transmission from micro remote sensing satellites, provided by an embodiment of this utility model. Figure 2 This is a top view schematic diagram of a slot waveguide array provided in an embodiment of the present invention; Figure 3 This is a bottom view schematic diagram of a coupled feed waveguide provided in an embodiment of this utility model; Figure 4 This is a schematic diagram of the structure of a waveguide phase shifter and a waveguide directional coupler provided in an embodiment of this utility model; Figure 5 This is a gain pattern provided by an embodiment of the present invention; Figure 6 This is an azimuth difference direction map provided in an embodiment of the present invention; Figure 7 This is a pitch difference pattern provided in an embodiment of the present invention.

[0016] Explanation of reference numerals in the attached figures: 1-Slot waveguide array; 11-Waveguide wide-side transverse slot; 2-Coupled feed waveguide; 21-First coupling slot; 22-Connection port; 3-Waveguide phase shifter; 31-First waveguide phase shifter; 32-Second waveguide phase shifter; 33-Third waveguide phase shifter; 34-Fourth waveguide phase shifter; 4-Waveguide directional coupler; 41-First port; 42-Second port; 43-Third port; 44-Fourth port; 45-Cross-shaped through-hole. Detailed Implementation

[0017] To further illustrate the technical means and effects adopted by this utility model to achieve its intended purpose, the following describes in detail, with reference to the accompanying drawings and specific embodiments, an adaptive pointing antenna applicable to the data transmission of micro remote sensing satellites proposed according to this utility model.

[0018] The foregoing and other technical contents, features, and effects of this utility model will be clearly presented in the following detailed description of the specific embodiments with reference to the accompanying drawings. Through the description of the specific embodiments, a more in-depth and specific understanding can be gained of the technical means and effects adopted by this utility model to achieve the intended purpose. However, the accompanying drawings are only provided for reference and illustration and are not intended to limit the technical solution of this utility model.

[0019] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations are intended to cover non-exclusive inclusion, such that an article or apparatus comprising a list of elements includes not only those elements but also other elements not expressly listed. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the article or apparatus that includes said element.

[0020] Please see Figure 1 , Figure 1 This is a schematic diagram showing the structural breakdown of an adaptive directional antenna applicable to data transmission from a small remote sensing satellite, according to an embodiment of this utility model. The antenna includes a slotted waveguide array 1, four coupled feed waveguides 2, four waveguide phase shifters 3, and four waveguide directional couplers 4. The upper surface of the slotted waveguide array 1 has 2n×2n transverse slots 11 along its wide side, dividing it into four sub-modules. Each sub-module includes n×n transverse slots 11 along its wide side, where n is an integer greater than or equal to 2. Each coupled feed waveguide 2 is connected to one of the four sub-modules for independent energy coupling to the current sub-module. The four waveguide directional couplers 4 are interconnected to form a cross-shaped coupling structure, which includes four ports. The first end of each waveguide phase shifter 3 is connected to the corresponding waveguide directional coupler 4, and the second end of each waveguide phase shifter 3 is connected to the corresponding coupled feed waveguide 2.

[0021] For preferred options, please refer to [link / reference]. Figure 2 , Figure 2 This is a top view schematic diagram of a slotted waveguide array provided in an embodiment of the present invention. The upper surface of the slotted waveguide array 1 in this embodiment has 12×12 transverse slots 11 along the wide side of the waveguide, divided into four sub-modules, such as... Figure 2 The diagram shows four sub-modules: A, B, C, and D. Each sub-module includes 6×6 waveguide wide-side transverse slots 11, each waveguide wide-side transverse slot 11 having the same length and width, and the length direction of each waveguide wide-side transverse slot 11 being parallel.

[0022] Furthermore, please also refer to Figure 1 and Figure 3 , Figure 3 This is a bottom-view structural diagram of a coupled-feed waveguide provided in an embodiment of the present invention. In this embodiment, four coupled-feed waveguides 2 are arranged in parallel. Each coupled-feed waveguide 2 has n first coupling slots 21 on its upper surface. Preferably, each coupled-feed waveguide 2 has six first coupling slots 21 on its upper surface. The length direction of each first coupling slot 21 is approximately the same as the length direction of the coupled-feed waveguide 2, but according to the actual design, there is a predetermined angle of inclination. Correspondingly, the lower surface of each sub-module of the slot waveguide array 1 has a second coupling slot (not shown in the figure) that coincides with the vertical projection of the first coupling slot 21 on the corresponding coupled-feed waveguide 2. Each coupled-feed waveguide 2 independently completes the energy coupling and feeding of one sub-module. That is, each coupled-feed waveguide 2 has six first coupling slots 21 on its upper surface, and correspondingly, each sub-module of the slot waveguide array 1 has six second coupling slots on its lower surface. The vertical projections of the six first coupling slots 21 and the six second coupling slots coincide pairwise.

[0023] The length direction of the coupled feed waveguide 2 is perpendicular to the length direction of the transverse slot 11 on the wide side of the waveguide. The first end of each coupled feed waveguide 2 is closed, and the second end includes a connection port 22 bent toward the waveguide phase shifter 3. The connection port 22 is connected to one of the four waveguide phase shifters 3. The signal phase shift of each coupled feed waveguide 2 is completed by a corresponding waveguide phase shifter 3.

[0024] Further, please see Figure 4 , Figure 4 This is a schematic diagram of a waveguide phase shifter and a waveguide directional coupler provided in an embodiment of the present invention. In this embodiment, four waveguide directional couplers 4 are interconnected to form a cross-shaped coupling structure, which includes four ports. The waveguide phase shifter 3 includes a first waveguide phase shifter 31, a second waveguide phase shifter 32, a third waveguide phase shifter 33, and a fourth waveguide phase shifter 34. The first waveguide phase shifter 31 is a reference phase waveguide phase shifter, the second waveguide phase shifter 32 is a λ / 4 phase waveguide phase shifter, the third waveguide phase shifter 33 is a λ / 2 phase waveguide phase shifter, and the fourth waveguide phase shifter 34 is a λ / 4 phase waveguide phase shifter.

[0025] The cross-shaped coupling structure includes a first port 41, a second port 42, a third port 43, and a fourth port 44. The first port 41 is the azimuth port, the second port 42 is the azimuth port, and the third and fourth ports 43 and 44 are connected to the load but do not transmit signals. Furthermore, the four waveguide directional couplers 4 are centrally symmetrically distributed, forming a cross-shaped through-hole 45 at the center.

[0026] In this embodiment, four waveguide phase shifters 3 and four waveguide directional couplers 4 work together to perform signal energy power division and phase shift, outputting four ports to realize signal combination among the four sub-modules of the slot waveguide array 1, thereby realizing data transmission and automatic measurement of directional offset.

[0027] When the antenna is operating, waveguide coaxial converters are installed at the four ports (port 41, port 42, port 43, and port 44) of the waveguide directional coupler 4, respectively, to receive external high-frequency current. The high-frequency current first flows into the waveguide directional coupler 4, and after being divided by the waveguide directional coupler 4, it enters the waveguide phase shifter 3. The signal undergoes phase shift, and the signal with determined amplitude and phase enters the coupling feed waveguide 2. The coupling feed waveguide 2 then feeds the slot waveguide array 1, where the high-frequency current is excited, forming electromagnetic waves radiated outward.

[0028] The process of receiving external electromagnetic waves is the reverse. Specifically, when an external electromagnetic wave illuminates the slotted waveguide array 1, it induces currents in the 12×12 transverse slots 11 along the wide side of the waveguide. These induced currents form guiding waves within the slotted waveguide array 1. These guiding waves then enter the coupled feed waveguide 2 and are transmitted in reverse to the waveguide phase shifter 3. In the waveguide phase shifter 3, the signal undergoes the same phase shifting process as during transmission, but in the opposite direction. The four phase-shifted signals enter the waveguide directional coupler 4, where, through reverse power splitting and combining, the signals from the four sub-modules of the slotted waveguide array 1 are combined into four output signals: port 41 outputs a signal (for data transmission), port 42 outputs an azimuth difference signal (for azimuth pointing error detection), port 43 outputs an elevation difference signal (for elevation pointing error detection), and port 44 connects to a load to absorb deviation energy. Ultimately, these four ports convert the radio frequency signals into high-frequency currents via waveguide-coaxial converters, which are then sent to the remote sensing satellite control center for processing, completing the reception process.

[0029] In practice, in the first port 41 working mode, the phases of the first waveguide phase shifter 31, the second waveguide phase shifter 32, the third waveguide phase shifter 33, and the fourth waveguide phase shifter 34 are all at the reference phase of 0°, coupled to the slot waveguide array 1. The four sub-modules are in phase, and their radiation patterns are superimposed in phase in space to form a signal. The first port 41 is connected to the data transmission channel of the remote sensing satellite control center for data transmission.

[0030] In the second port 42 operating mode, the first waveguide phase shifter 31 and the second waveguide phase shifter 32 are in phase of 180°, and the third waveguide phase shifter 33 and the fourth waveguide phase shifter 34 are in phase of 0°. They are coupled and fed to the slot waveguide array 1. In the four sub-modules, module A (connected to the first waveguide phase shifter 31 through a coupled feeding waveguide 2) and module B (connected to the second waveguide phase shifter 32 through a coupled feeding waveguide 2) are in phase of 180°, and module C (connected to the third waveguide phase shifter 33 through a coupled feeding waveguide 2) and module D (connected to the fourth waveguide phase shifter 34 through a coupled feeding waveguide 2) are in phase of 0°. The radiation patterns are superimposed in space to form an azimuth difference signal of A+B-(C+D). The second port 42 is connected to the azimuth control channel of the remote sensing satellite control center. When the azimuth of the satellite antenna is aligned with the ground station receiving antenna, the magnitudes of signals A+B and C+D are equal, and the output of the second port 42 is a very small level signal; the azimuth control program does not start. When the azimuth of the satellite antenna deviates from the ground station receiving antenna, the magnitudes of signals A+B and C+D are different, indicating a deviation. The output signal of the second port 42 increases sharply, the azimuth control program starts, and corrects the satellite attitude according to the deviation value, achieving the goal of adjusting the antenna azimuth. After adjustment, when the azimuth angle of the satellite antenna is aligned with the azimuth angle of the ground station receiving antenna again, the magnitudes of signals A+B and C+D are equal, the azimuth control program closes, and closed-loop control is completed.

[0031] In the third port 43 operating mode, the first waveguide phase shifter 31 and the fourth waveguide phase shifter 34 are in phase with 180°, and the second waveguide phase shifter 32 and the third waveguide phase shifter 33 are in phase with 0°. They are coupled and fed to the slotted waveguide array 1. In the four sub-modules, modules A and D are in phase with 180°, and modules B and C are in phase with 0°. The radiation patterns are superimposed in space to form an A+D-(B+C) pitch difference signal. The third port 43 is connected to the pitch control channel of the remote sensing satellite control center. When the satellite antenna pitch is aligned with the ground station receiving antenna, the A+D and B+C signals are equal in magnitude, and the output of the third port 43 is a very small level signal, and the pitch control program is not started. When the satellite antenna pitch deviates from the ground station receiving antenna, the A+D and B+C signals are different in magnitude, with a deviation value. The output signal of the third port 43 increases sharply, the pitch control program is started, and the satellite attitude is corrected according to the deviation value to achieve the goal of adjusting the antenna pitch. After adjustment, when the satellite's antenna elevation angle is aligned with the ground station's receiving antenna elevation angle again, the magnitudes of the A+D and B+C signals are equal, the elevation control program is closed, and closed-loop control is completed. Therefore, the adaptive pointing antenna provided by this invention can automatically measure the pointing offset as an input parameter for satellite attitude adjustment, and can also evaluate the accuracy of the adjusted antenna pointing angle.

[0032] The adaptive pointing antenna in this embodiment operates in the frequency band of 8~8.4GHz. In the first port 41 operating mode, it forms and signals. Please refer to [link to relevant documentation]. Figure 5 , Figure 5 This embodiment of the present invention provides a gain radiation pattern, wherein the horizontal axis represents angle in degrees, the vertical axis represents gain in dBi, and the operating frequency is 8.2 GHz. It can be seen that the antenna gain is at its maximum at this point, and the first port 41 is connected to the data transmission channel of the remote sensing satellite control center for data transmission.

[0033] In the second port 42 operating mode, an azimuth difference signal of A+B-(C+D) is generated, such as... Figure 6 As shown, there is a zero depth in the center direction. The second port 42 is connected to the azimuth control channel of the remote sensing satellite control center, and corrects the satellite attitude based on the deviation value to achieve the goal of adjusting the antenna azimuth pointing.

[0034] Furthermore, in the third port 43 operating mode, an A+D-(B+C) pitch difference signal is generated, such as... Figure 7 As shown, there is a zero depth in the center direction. The third port 43 is connected to the elevation control channel of the remote sensing satellite control center, and corrects the satellite attitude according to the deviation value to achieve the goal of adjusting the antenna elevation pointing.

[0035] As can be seen from the above analysis, the adaptive pointing antenna of this invention, which can be applied to the data transmission of micro remote sensing satellites, can realize data transmission and automatic measurement of pointing offset through the combination of signals from four ports, thereby achieving adaptive pointing tracking.

[0036] This invention relates to an adaptive pointing antenna with a purely passive architecture, resulting in low power consumption and low cost. Structurally, it employs a waveguide stacking method, making it small in size and lightweight. Through signal combination at four ports, it enables data transmission and automatic measurement of pointing offset, achieving adaptive pointing tracking, making it ideal for use on miniature remote sensing satellite platforms.

[0037] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the protection scope of the present invention.

Claims

1. An adaptive pointing antenna applicable to data transmission from micro remote sensing satellites, characterized in that, It includes a slotted waveguide array (1), four coupled-feed waveguides (2), four waveguide phase shifters (3), and four waveguide directional couplers (4), wherein, The slot waveguide array (1) has 2n×2n waveguide wide-side transverse slots (11), and is divided into four sub-modules. Each sub-module has n×n waveguide wide-side transverse slots (11), where n is an integer greater than or equal to 2. Each of the coupled feed waveguides (2) is connected to one of the four sub-modules for independent energy coupling to the current sub-module; The four waveguide directional couplers (4) are interconnected to form a cross-shaped coupling structure, which includes four ports; The first end of each waveguide phase shifter (3) is connected to the corresponding waveguide directional coupler (4), and the second end of each waveguide phase shifter (3) is connected to the corresponding coupled feed waveguide (2).

2. The adaptive pointing antenna applicable to data transmission from micro remote sensing satellites according to claim 1, characterized in that, Each of the waveguide wide-side transverse slots (11) has the same length and width, and the length direction of each waveguide wide-side transverse slot (11) is parallel.

3. The adaptive pointing antenna applicable to data transmission from micro remote sensing satellites according to claim 1, characterized in that, The four coupled-feed waveguides (2) are arranged in parallel, and each coupled-feed waveguide (2) has n first coupling slots (21) on its upper surface.

4. The adaptive pointing antenna applicable to data transmission from micro remote sensing satellites according to claim 3, characterized in that, The length direction of the coupled feed waveguide (2) is perpendicular to the length direction of the transverse slot (11) on the wide side of the waveguide.

5. The adaptive pointing antenna applicable to data transmission from micro remote sensing satellites according to claim 3, characterized in that, Each sub-module of the slot waveguide array (1) has n second coupling slots on its lower surface, and the second coupling slots coincide with the vertical projection of the first coupling slot (21) on the corresponding coupled feed waveguide (2).

6. The adaptive pointing antenna applicable to data transmission from micro remote sensing satellites according to claim 1, characterized in that, Each of the coupled-feed waveguides (2) has a first end short-circuited and a second end including a connection port (22) bent toward the waveguide phase shifter (3) and connected to one of the four waveguide phase shifters (3) through the connection port (22).

7. The adaptive pointing antenna applicable to data transmission from micro remote sensing satellites according to claim 1, characterized in that, The four waveguide phase shifters (3) include a first waveguide phase shifter (31), a second waveguide phase shifter (32), a third waveguide phase shifter (33), and a fourth waveguide phase shifter (34), wherein, The first waveguide phase shifter (31) is a reference phase waveguide phase shifter, the second waveguide phase shifter (32) is a λ / 4 phase waveguide phase shifter, the third waveguide phase shifter (33) is a λ / 2 phase waveguide phase shifter, and the fourth waveguide phase shifter (34) is a λ / 4 phase waveguide phase shifter.

8. The adaptive pointing antenna applicable to data transmission of micro remote sensing satellites according to claim 1, characterized in that, The cross-shaped coupling structure includes a first port (41), a second port (42), a third port (43), and a fourth port (44), wherein, The first port (41) is a junction port, the second port (42) is an azimuth difference port, and the third port (43) and the fourth port (44) are connected to the load.

9. The adaptive pointing antenna applicable to data transmission from micro remote sensing satellites according to claim 1, characterized in that, The four waveguide directional couplers (4) are centrally symmetrically distributed, with a cross-shaped through hole (45) formed in the center.

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