Method and system for aligning a two-dimensional point beam data transmission satellite antenna in wireless docking

Abstract

The application provides a two-dimensional point beam data transmission satellite antenna alignment method and system in wireless docking, comprising the following steps: S1, coarsely aligning a ground receiving antenna and a data transmission satellite antenna; S2, aligning the data transmission satellite antenna obtained in the step S1 in the elevation direction; S3, aligning the data transmission satellite antenna obtained in the step S2 in the horizontal direction; and S4, verifying the signal-to-noise ratio according to the data transmission satellite antenna obtained in the step S3. The application drives the two-dimensional point beam data transmission antenna to rotate by a ground test platform, and judges the alignment condition by combining the antenna directional diagram with the received signal power of a ground spectrum analyzer, so that the ground receiving antenna and the data transmission satellite antenna can be quickly and effectively aligned.

Description

Technical Field

[0001] This invention belongs to the technical field of large-scale satellite-to-ground systems, specifically relating to a method and system for aligning two-dimensional point beam data transmission satellite antennas in wireless docking. Background Technology

[0002] During satellite development, large-scale satellite-to-ground system docking tests are required to ensure that the ground can demodulate, receive, store, and distribute high-frequency signals output by the satellite during its on-orbit operation. During satellite-to-ground wireless docking tests, the onboard antenna needs to be placed at a high location, such as a mountaintop, far from the ground receiving antenna, to test whether the ground can receive the satellite signals in wireless mode. In long-distance tests, especially for point-beam data transmission satellite antennas with small beam angles, the process of adjusting the data transmission satellite antenna to align with the ground receiving antenna consumes a significant amount of test time.

[0003] Currently, it is impossible to quickly adjust the ground receiving antenna and the data transmission satellite antenna using effective testing equipment or visual methods to achieve precise alignment.

[0004] Patent document CN103217596A discloses a ground verification method for the performance of a dual-circularly polarized multiplexed satellite data transmission antenna. This method involves setting a modulator to transmit a single-carrier signal at maximum power, using a spectrum analyzer to measure and record the signal from a specific channel transmitted by the satellite data transmission antenna, and then sequentially adjusting the azimuth and elevation angles of both the ground receiving antenna and the satellite data transmission antenna. The pointing angle of the satellite data transmission antenna recorded when the spectrum analyzer receives the maximum power is the alignment angle. However, this method has drawbacks: it requires both the ground receiving antenna and the satellite data transmission antenna to rotate within a large angle range; it also relies on the output signal of only one channel; after determining the pointing angle at the maximum signal power, it does not test or verify the output signal power of the other channel; and the antenna alignment in this method is limited by the antenna rotation accuracy, failing to meet the requirements for rapid and accurate antenna alignment during satellite-to-ground wireless docking tests.

[0005] Patent document CN114499637A discloses a method and system for satellite-to-ground data transmission docking between a ground receiving station and a satellite. It proposes that during the alignment of the satellite-borne data transmission antenna, the maximum signal output power P can be determined based on the symmetry of the radiation pattern of the point beam transmitting antenna. max After setting the antenna pointing angle to dB, gradually deflect the antenna in both the elevation and azimuth directions using this as the center until its ground received power value is P. max-3dB. If the antenna pointing angle at this time is symmetrical with the antenna pointing angle corresponding to the maximum value of the received signal power, it can be determined that the antenna is successfully aligned. However, its disadvantage is that when the distance between the ground receiving antenna and the data transmission satellite antenna is too far (too far means on the order of kilometers), it is impossible to record and compare the output signal power of the data transmission satellite antenna within the full pointing angle range. This may cause the antenna to be mistakenly pointed to the side lobe of the data transmission satellite antenna pattern, thus missing the actual alignment angle between the ground receiving antenna and the data transmission satellite antenna.

[0006] Patent document CN116130959A discloses an antenna alignment control method and device, which achieves alignment by acquiring the latitude and longitude information and orientation information of the target device and the antenna and adjusting the antenna pointing angle. However, this method is not suitable for point beam antennas with high pointing accuracy.

[0007] Patent document CN113871875A discloses a method, device and terminal for automatic antenna alignment in a beyond-line-of-sight wireless communication system. The antenna alignment angle is determined in the elevation direction based on the received signal strength, but no precise antenna pointing alignment is performed in the horizontal direction, making it unsuitable for two-dimensional pointing antennas.

[0008] Patent document CN111276818A discloses a control device and algorithm for aligning an antenna with a target position. It calculates the antenna orientation using the coordinate information of the first antenna positioning module and the second antenna positioning module in the device, and calculates the maximum radiation direction of the antenna based on the antenna orientation. After comparing the maximum radiation direction with the orientation of the target position, it calculates the minimum angle that the antenna needs to rotate. Its disadvantage is that after obtaining the antenna alignment pointing angle, it is necessary to judge whether the antenna is in line with the correct pointing by the received signal power. If it is not in line with the correct pointing angle, the position information and the maximum radiation direction need to be recalculated. Summary of the Invention

[0009] To address the shortcomings of existing technologies, the purpose of this invention is to provide a method and system for aligning two-dimensional point beam data transmission satellite antennas in wireless docking.

[0010] A method for aligning a two-dimensional spot-beam data transmission satellite antenna in wireless docking, provided by the present invention, includes: Step S1: Perform coarse alignment of the ground receiving antenna and the data transmission satellite antenna; Step S2: Align the data transmission satellite antenna in the elevation direction; Step S3: Align the data transmission satellite antenna horizontally; Step S4: Verify the signal-to-noise ratio of the received signal from the ground receiving antenna corresponding to the data transmission satellite antenna. If the verification is successful, the data transmission satellite antenna and the ground receiving antenna are considered to be aligned. If the verification fails, step S2 is triggered to continue execution.

[0011] Preferably, in step S1: the ground receiving antenna is rotated to the direction of the data transmission satellite antenna, and it is ensured that there are no buildings obstructing the wireless communication link to complete the coarse alignment; In step S2: Keep the horizontal pointing angle of the data transmission satellite antenna unchanged, rotate the pointing angle in the pitch direction, and record the angle corresponding to the extreme value of the ground receiving signal power of the ground receiving antenna during the rotation of the data transmission satellite antenna, so as to determine and complete the pitch direction alignment. The range of rotation of the data transmission satellite antenna in the elevation direction (+θ) Ymax ,-θ Ymax Within the range, a scan is performed from +Y to -Y with an elevation step angle Δθ1. During the scan, the change in the ground received radio frequency signal power of the ground receiving antenna is monitored, and two signal power minima are recorded, denoted as W. Y1 W Y2 The pointing angles in the pitch direction corresponding to the two minimum values ​​are denoted as θ. Y1 θ Y2 θ Y =(θ Y1 +θ Y2 ) / 2, θ Y This refers to the elevation angle when the ground receiving antenna and the data transmission satellite antenna are aligned.

[0012] Preferably, in step S3: Keeping the pointing angle of the data transmission satellite antenna in the elevation direction unchanged, rotate the pointing angle of the data transmission satellite antenna in the horizontal direction, and record the angle corresponding to the extreme value of the ground received signal power during the rotation of the data transmission satellite antenna, so as to determine and complete the horizontal alignment. The data transmission satellite antenna is in the horizontal direction within the antenna rotation range (+θ) Xmax ,-θ Xmax Within the range, a rapid scan is performed from +X to -X with a horizontal step angle Δθ2. During the scan, the change in the ground-received radio frequency signal power of the ground receiving antenna is monitored, and two signal power minimum values ​​W are recorded. X1 W X2 The horizontal pointing angles corresponding to the two minimum values ​​are θ and θ, respectively. X1 θ X2 θ X =(θ X1 +θ X2 ) / 2, θ X This refers to the horizontal angle when the ground receiving antenna and the data transmission satellite antenna are aligned. Keep the horizontal direction pointing at angle θ X Unchanged, with θ YCentered on the angle, the antenna rotation step angle is reduced to drive the data transmission satellite antenna, which rotates within a small angle range in the elevation direction, refining the pointing angle in the elevation direction and gradually approaching the elevation angle θ that the ground receiving antenna and the data transmission satellite antenna are aligned with. YO ; Maintain the pointing angle θ in the pitch direction YO Unchanged, with θ X Centered on the angle, the antenna rotation step angle is reduced to drive the data transmission satellite antenna to rotate within a small angle range in the horizontal direction, refining the horizontal pointing angle of the antenna and gradually approaching the horizontal angle θ between the ground receiving antenna and the data transmission satellite antenna. XO .

[0013] Preferably, in step S4: given that the distance between the data transmission satellite antenna and the ground receiving antenna is measurable, the antenna gain is determined, the signal received power is measurable, and the space environment loss, antenna pointing loss, and link loss are fixed, the theoretical signal-to-noise ratio of the ground system to which the ground receiving antenna belongs is determined. Compared with the measured signal-to-noise ratio, if the measured signal-to-noise ratio is greater than or equal to the theoretical received signal-to-noise ratio of the ground system... This indicates that the antenna is aligned; if the measured signal-to-noise ratio is less than the theoretical signal-to-noise ratio of the ground system's received signal, then the antenna is aligned. If so, it indicates that the antenna is not aligned; Let the spectrum analyzer of the ground system calibrate the signal output power at the input of the satellite data transmission antenna to be P. t The gain of the data transmission satellite antenna is G. t The isotropic radiated power of the satellite portion for: (1) Signal free space loss between satellite-borne data transmission antenna and ground receiving antenna for: (2) Where d is the propagation distance; The radiation frequency; Theoretical signal-to-noise ratio of ground system received signal for: -K(3) in, This represents the theoretically received useful signal power of the ground system. This represents the theoretical received noise signal power of the ground system. L r Indicates rainfall loss, L a Indicates atmospheric loss. L p Indicates polarization loss. Lrp G represents the antenna pointing loss; G / T represents the antenna gain to noise-temperature ratio of the ground receiving system, where G represents the antenna gain of the ground system, T represents the noise-temperature of the ground system, and K is the logarithm of Boltzmann's constant.

[0014] Preferably, the theoretical signal-to-noise ratio of the ground system when the ground receiving antenna and the data transmission satellite antenna are aligned is obtained based on the RF wired link loss, RF signal free space loss, antenna pointing loss, and the gain of the data transmission satellite antenna and the ground receiving antenna.

[0015] A two-dimensional spot-beam data transmission satellite antenna alignment system for wireless docking, provided by the present invention, includes: Module M1: Performs coarse alignment of the ground receiving antenna and the data transmission satellite antenna; Module M2: Aligns the data transmission satellite antenna in the elevation direction; Module M3: Horizontally aligns the data transmission satellite antenna; Module M4: Performs signal-to-noise ratio verification on the received signal of the ground receiving antenna corresponding to the data transmission satellite antenna. If the verification passes, the data transmission satellite antenna is considered to be aligned with the ground receiving antenna; if the verification fails, module M2 is triggered to continue execution.

[0016] Preferably, in module M1: the ground receiving antenna is rotated to the direction of the data transmission satellite antenna, and it is ensured that there are no buildings obstructing the wireless communication link to complete the coarse alignment; In module M2: keep the horizontal pointing angle of the data transmission satellite antenna unchanged, rotate the pointing angle in the pitch direction, and record the angle corresponding to the extreme value of the ground receiving signal power of the ground receiving antenna during the rotation of the data transmission satellite antenna, so as to determine and complete the pitch direction alignment. The range of rotation of the data transmission satellite antenna in the elevation direction (+θ) Ymax ,-θ Ymax Within the range, a scan is performed from +Y to -Y with an elevation step angle Δθ1. During the scan, the change in the ground received radio frequency signal power of the ground receiving antenna is monitored, and two signal power minima are recorded, denoted as W. Y1 W Y2 The pointing angles in the pitch direction corresponding to the two minimum values ​​are denoted as θ. Y1 θ Y2 θ Y =(θ Y1 +θ Y2 ) / 2, θ Y This refers to the elevation angle when the ground receiving antenna and the data transmission satellite antenna are aligned.

[0017] Preferably, in module M3: Keeping the pointing angle of the data transmission satellite antenna in the elevation direction unchanged, rotate the pointing angle of the data transmission satellite antenna in the horizontal direction, and record the angle corresponding to the extreme value of the ground received signal power during the rotation of the data transmission satellite antenna, so as to determine and complete the horizontal alignment. The data transmission satellite antenna is in the horizontal direction within the antenna rotation range (+θ) Xmax ,-θ Xmax Within the range, a rapid scan is performed from +X to -X with a horizontal step angle Δθ2. During the scan, the change in the ground-received radio frequency signal power of the ground receiving antenna is monitored, and two signal power minimum values ​​W are recorded. X1 W X2 The horizontal pointing angles corresponding to the two minimum values ​​are θ and θ, respectively. X1 θ X2 θ X =(θ X1 +θ X2 ) / 2, θ X This refers to the horizontal angle when the ground receiving antenna and the data transmission satellite antenna are aligned. Keep the horizontal direction pointing at angle θ X Unchanged, with θ Y Centered on the angle, the antenna rotation step angle is reduced to drive the data transmission satellite antenna, which rotates within a small angle range in the elevation direction, refining the pointing angle in the elevation direction and gradually approaching the elevation angle θ that the ground receiving antenna and the data transmission satellite antenna are aligned with. YO ; Maintain the pointing angle θ in the pitch direction YO Unchanged, with θ X Centered on the angle, the antenna rotation step angle is reduced to drive the data transmission satellite antenna to rotate within a small angle range in the horizontal direction, refining the horizontal pointing angle of the antenna and gradually approaching the horizontal angle θ between the ground receiving antenna and the data transmission satellite antenna. XO .

[0018] Preferably, in module M4: under the premise that the distance between the data transmission satellite antenna and the ground receiving antenna is measurable, the antenna gain is determined, the signal received power is measurable, and the space environment loss, antenna pointing loss, and link loss are fixed, the theoretical signal-to-noise ratio of the ground system to which the ground receiving antenna belongs is... Compared with the measured signal-to-noise ratio, if the measured signal-to-noise ratio is greater than or equal to the theoretical received signal-to-noise ratio of the ground system... This indicates that the antenna is aligned; if the measured signal-to-noise ratio is less than the theoretical signal-to-noise ratio of the ground system's received signal, then the antenna is aligned. If so, it indicates that the antenna is not aligned; Let the spectrum analyzer of the ground system calibrate the signal output power at the input of the satellite data transmission antenna to be P. t The gain of the data transmission satellite antenna is G. tThe isotropic radiated power of the satellite portion for: (1) Signal free space loss between satellite-borne data transmission antenna and ground receiving antenna for: (2) Where d is the propagation distance; The radiation frequency; Theoretical signal-to-noise ratio of ground system received signal for: -K(3) in, This represents the theoretically received useful signal power of the ground system. This represents the theoretical received noise signal power of the ground system. L r Indicates rainfall loss, L a Indicates atmospheric loss. L p Indicates polarization loss. L rp G represents the antenna pointing loss; G / T represents the antenna gain to noise-temperature ratio of the ground receiving system, where G represents the antenna gain of the ground system, T represents the noise-temperature of the ground system, and K is the logarithm of Boltzmann's constant.

[0019] Preferably, the theoretical signal-to-noise ratio of the ground system when the ground receiving antenna and the data transmission satellite antenna are aligned is obtained based on the RF wired link loss, RF signal free space loss, antenna pointing loss, and the gain of the data transmission satellite antenna and the ground receiving antenna.

[0020] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention can determine the antenna alignment angle in the elevation direction and the antenna alignment angle in the horizontal direction, and is applicable to two-dimensional directional antennas.

[0021] 2. This invention uses a ground test platform to drive the rotation of a two-dimensional point beam data transmission antenna and combines the antenna pattern with the signal power received by the ground spectrum analyzer to determine the alignment status, which can quickly and effectively complete the alignment of the ground receiving antenna and the data transmission satellite antenna.

[0022] 3. This invention improves the alignment efficiency of the ground receiving antenna and the data transmission satellite antenna by comparing the signal-to-noise ratio of the received signal with the theoretically calculated signal-to-noise ratio. Attached Figure Description

[0023] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Figure 1 This is a schematic diagram of the space-to-ground system provided by the present invention.

[0024] Figure 2 The radiation pattern of the data transmission satellite antenna provided by this invention.

[0025] Figure 3 A flowchart illustrating the alignment of the ground receiving antenna and the data transmission satellite antenna provided by this invention. Detailed Implementation

[0026] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0027] This invention provides a method and system for aligning a two-dimensional point-beam data transmission satellite-borne antenna in wireless docking, applicable to satellite-to-ground data transmission wireless docking experiments using low-Earth orbit satellites as an example, including: The effective remote sensing data from the satellite is written into the data transmission data storage unit via a data simulation source and transmitted to the modulator via a high-speed interface. The modulator performs data encoding and modulation on the remote sensing data. The processed signal is then output to the data transmission satellite antenna used in satellite wireless docking via an RF cable and a waveform converter. An adjustable attenuator is connected in series at the cable end of the data transmission satellite antenna to adjust the RF signal power. The data transmission satellite antenna has dual-channel polarization (left and right rotation) and can simultaneously receive RF signals from two modulators. The distance between the data transmission satellite antenna and the ground receiving antenna is d km, where d is greater than or equal to 1, meaning the distance between the data transmission satellite antenna and the ground receiving antenna is on the order of kilometers. In the overall satellite-ground test system, except for the adjustable signal attenuation parts of the ground system and on-board products, the remaining parts remain unchanged.

[0028] The onboard modulator receives fixed frame data from the satellite, encodes and modulates it to obtain processed data, outputs the processed data to the data transmission satellite antenna to obtain a valid signal, and then radiates the valid signal out by the data transmission satellite antenna.

[0029] The ground system receives the satellite's output radio frequency signal in real time, demodulates the data, and checks whether the received data is continuous and normal, and whether there are any errors. It compares the signal-to-noise ratio of the received signal with the theoretically calculated signal-to-noise ratio to confirm whether the ground receiving antenna and the data transmission satellite antenna are aligned.

[0030] After the satellite-borne unit outputs a valid signal, the spectrum analyzer calibrates the signal output power at the satellite-borne antenna input to be P. t The ground receiving system and satellite section are based on the output power P t Adjust the signal attenuation value within the system. The gain of the data transmission satellite antenna is G. t The isotropic radiated power of the satellite portion for: (1) Signal free space loss between satellite-borne data transmission antenna and ground receiving antenna for: (2) Where d is the propagation distance, in km; The radiation frequency is expressed in GHz.

[0031] Theoretical signal-to-noise ratio of ground system received signal for: -K(3) in, This represents the theoretically received useful signal power of the ground system. This represents the theoretical received noise signal power of the ground system. L r Indicates rainfall loss, L a Indicates atmospheric loss. L p Indicates polarization loss. L rp G represents the antenna pointing loss, in dB; G / T represents the antenna gain to noise-temperature ratio of the ground system, in dB / K, where G represents the antenna gain of the ground system, T represents the noise-temperature of the ground system, and K is the logarithm of Boltzmann's constant, in dB.

[0032] A method for aligning a two-dimensional spot-beam data transmission satellite antenna in wireless docking, provided by the present invention, includes: Step S1: Perform coarse alignment of the ground receiving antenna and the data transmission satellite antenna; Step S2: Align the data transmission satellite antenna obtained in step S1 in the elevation direction; Step S3: Align the data transmission satellite antenna obtained in step S2 in the horizontal direction; Step S4: Verify the signal-to-noise ratio based on the data transmission satellite antenna obtained in step S3.

[0033] Specifically, during the coarse alignment of the ground receiving antenna and the data transmission satellite antenna, the ground receiving antenna first controls the antenna driving device according to the tracking command through the servo tracking system, so that the ground receiving antenna rotates to the direction of the data transmission satellite antenna, and ensures that there are no buildings or other obstructions in the wireless communication link.

[0034] A single-carrier signal is emitted by the spaceborne modulator and radiated to the ground via the data transmission spaceborne antenna until the ground receiving system's spectrum analyzer can receive the effective single-carrier signal, thus enabling visual coarse alignment between the data transmission spaceborne antenna and the ground receiving antenna at a long distance.

[0035] In other words, the direction of the data transmission satellite antenna pointing to the ground receiving antenna is adjusted visually, and the corresponding command is sent through the ground detection equipment to make the satellite modulator output a single carrier signal until the spectrum analyzer of the ground receiving system simultaneously receives the two left and right rotating single carrier signals transmitted from the satellite and the ground; the signal power and the pointing angle of the data transmission satellite antenna at this time are recorded.

[0036] In other words, the ground receiving antenna and the data transmission satellite antenna are coarsely aligned. The satellite data simulation source sends simulated remote sensing data to the data transmission data storage unit, which completes the data framing and scheduling to obtain the processed data. The processed data is then transmitted to the satellite modulator, which modulates the effective signal and outputs it. The two signals are then input to the signal input of the two-dimensional spot beam data transmission satellite antenna via an RF cable.

[0037] First, the ground receiving antenna is rotated to its receiving range, ensuring there are no obvious obstructions on all sides, and then the angle is kept fixed. The data transmission satellite antenna is small, lightweight, and easy to adjust; therefore, the subsequent rotation is primarily driven by the ground-based data transmission satellite antenna test platform. Once the ground receiving system receives a valid RF signal from the data transmission subsystem, the coarse alignment of the ground receiving antenna and the data transmission satellite antenna is complete. The ground receiving antenna simultaneously receives left and right-hand dual-polarized signals. The RF signals are processed through couplers, RF switch matrices, etc., and then output to a spectrum analyzer, which simultaneously records the output power of the left and right-hand channels. Specifically, after the ground receiving antenna and the data transmission satellite antenna are successfully coarsely aligned, the data transmission two-dimensional spot beam antenna is driven by the ground test platform to rotate within the range of +θ in the elevation direction. Ymax ,-θ Ymax Within the range of +Y to -Y, a rapid scan is performed with an elevation step angle Δθ1, while the horizontal antenna pointing angle remains constant. During the scan, the changes in the power of the received radio frequency signal on the ground are monitored, and two minimum power values ​​are recorded, denoted as W. Y1 W Y2 And the pointing angles of the pitch direction corresponding to the two minimum values, denoted as θ. Y1 θ Y2 Calculate the distance θ between two angles.Y =(θ Y1 +θ Y2 ) / 2, θ Y That is, the pitch angle when the ground receiving antenna and the data transmission satellite antenna are aligned. In other words, during antenna rotation, the signal power received by the two-channel spectrum analyzer in the ground system is detected and recorded. Based on the test data, the antenna pointing angle θ corresponding to the minimum values ​​of the two signal powers during antenna elevation rotation is selected. Y1 θ Y2 The pitch angle θ in the aligned state is calculated. Y =(θ Y1 +θ Y2 ) / 2.

[0038] In this example, keeping the horizontal angle of the data transmission satellite antenna constant, the ground test platform drives the antenna to rotate within the full range of elevation angles. For the initial full-range rotation, a larger rotation step angle can be set. Taking the antenna's deployed state as the initial pointing angle (0°, 0°), the antenna's elevation rotation range is -68.5° to +68.5°, and its horizontal rotation range is -85° to +68.5°. The antenna rotation step angle is set to 1°, and the antenna's rotation speed can be adjusted according to the ground receiving antenna test platform. In this example, the antenna rotation speed is adjustable within the range of 0.05° / s to 0.1° / s.

[0039] In other words, elevation alignment involves, under the premise that the ground system can receive the radio frequency signal transmitted by the data transmission satellite antenna, increasing the antenna rotation step angle according to the antenna's rotation range. At a certain constant step angle, the ground test platform drives the data transmission satellite antenna to perform a rapid full-angle scan in the elevation direction. The ground system records the angle corresponding to the extreme value of the received signal power during antenna rotation. The midpoint between the pointing angles corresponding to the two minimum values ​​of the received signal power is the alignment angle. Within the angle range corresponding to the minimum signal power, the driving step angle of the ground test platform is refined, and the signal power values ​​of the left and right rotating channels received by the ground spectrum analyzer are recorded. The pointing angle corresponding to the maximum signal power obtained during this rotation is the elevation alignment angle.

[0040] The data transmission satellite antenna is rotated to θ. Y The angle is fixed, and the data transmission satellite antenna is driven by the ground test platform in the horizontal direction, within the antenna rotation range (+θ). Xmax ,-θ Xmax Within this range, a rapid scan is performed from +X to -X with a horizontal step angle Δθ2. Furthermore, the signal power values ​​received by the ground spectrum analyzer are recorded during the scan, and the two signal power minimums are recorded as W. X1 W X2The corresponding pointing angles are θ X1 θ X2 Calculate the distance θ between two angles. X =(θ X1 +θ X2 ) / 2, θ X This refers to the horizontal angle when the ground receiving antenna and the data transmission satellite antenna are aligned. In other words, the elevation direction of the data transmission satellite antenna is fixed at θ. Y The antenna is rotated horizontally at a full 360 degrees. The changes in the ground-received signal power during this rotation are recorded, and the horizontal pointing angle corresponding to the minimum signal power is recorded as θ. X1 θ X2 Then the horizontal angle in the aligned state is θ. X =(θ X1 +θ X2 ) / 2.

[0041] To accurately determine the antenna pointing angle, with (θ) X θ Y Centered on an angle, reduce the rotation step angle of the data transmission satellite antenna, and offset the data transmission satellite antenna in the elevation and horizontal directions respectively. Record the signal power received on the ground during the antenna rotation process, and the antenna pointing angle (θ) when the ground received signal strength is the maximum. XO ,θ YO ( ) is the alignment angle.

[0042] In other words, horizontal alignment means that after determining the alignment angle of the data transmission satellite antenna's elevation direction, the elevation direction of the data transmission satellite antenna is fixed at this angle. The ground test platform drives the data transmission satellite antenna to rotate at all angles in the horizontal direction. After the ground spectrum analyzer collects the first minimum value of the output signal power, the driving step angle of the ground test platform can be gradually reduced until the maximum value of the output signal power is reached. The data transmission satellite antenna is then driven to rotate. If a second minimum value of signal power equivalent to the first minimum value is detected, it indicates that the horizontal angle corresponding to the maximum signal power between the two minimum values ​​is the angle under alignment between the ground receiving antenna and the data transmission satellite antenna.

[0043] If the antenna has a large range of rotation, then perform full-angle rotation with a large step angle to determine the initial range of the antenna alignment angle, and then gradually reduce the antenna rotation step angle to gradually approach the center angle.

[0044] In other words, after initially determining the elevation direction and horizontal pointing angle of the data transmission satellite antenna, the horizontal pointing angle θ is maintained. X Unchanged, with θ YCentered on the angle, the antenna rotation step angle is reduced to drive the data transmission satellite antenna to rotate within a small angle range in the elevation direction, refining the pointing angle in the antenna elevation direction and gradually approaching the elevation angle θ that the ground receiving antenna and the data transmission satellite antenna are aligned with. YO .

[0045] Maintain the pointing angle θ in the pitch direction YO Unchanged, with θ X Centered on the angle, the antenna rotation step angle is reduced to drive the data transmission satellite antenna to rotate within a small angle range in the horizontal direction, refining the antenna's horizontal pointing angle and gradually approaching the optimal horizontal angle θ for alignment between the ground receiving antenna and the data transmission satellite antenna. XO .

[0046] After determining the pointing angle of the ground receiving antenna, the onboard product section sends out the payload data. The ground receiving system records the measured signal-to-noise ratio (SNR) and the theoretically calculated SNR under the condition that there are no errors in the ground reception. If the measured SNR is not less than the theoretical SNR, it indicates that the antenna is aligned.

[0047] In other words, signal-to-noise ratio (SNR) verification, which involves determining the antenna alignment angle, and under the premise that the distance between the data transmission satellite antenna and the ground receiving antenna is measurable, the antenna gain is determined, the signal received power is measurable, and the space environment loss, antenna pointing loss, and link loss are fixed, can compare the theoretically calculated SNR with the measured SNR. If the measured SNR is not less than the theoretical SNR, it indicates that the antenna is aligned.

[0048] In addition, the theoretical signal-to-noise ratio when the ground receiving antenna and the data transmission satellite antenna are aligned is obtained based on the RF wired link loss, RF signal free space loss, antenna pointing loss, and the gain of the data transmission satellite antenna and the ground receiving antenna.

[0049] The two-dimensional spot-beam data transmission satellite-borne antenna alignment system for wireless docking provided by this invention can be implemented by executing the steps of the two-dimensional spot-beam data transmission satellite-borne antenna alignment method for wireless docking. That is, the two-dimensional spot-beam data transmission satellite-borne antenna alignment method for wireless docking can be understood as a specific implementation of the two-dimensional spot-beam data transmission satellite-borne antenna alignment system for wireless docking.

[0050] A two-dimensional spot-beam data transmission satellite antenna alignment system for wireless docking, provided by the present invention, includes: Module M1: Performs coarse alignment of the ground receiving antenna and the data transmission satellite antenna; Module M2: Aligns the data transmission satellite antenna in the elevation direction; Module M3: Horizontally aligns the data transmission satellite antenna; Module M4: Performs signal-to-noise ratio verification on the received signal of the ground receiving antenna corresponding to the data transmission satellite antenna. If the verification passes, the data transmission satellite antenna is considered to be aligned with the ground receiving antenna; if the verification fails, module M2 is triggered to continue execution.

[0051] In module M1: the ground receiving antenna is rotated to the direction of the data transmission satellite antenna, and it is ensured that there are no buildings obstructing the wireless communication link to complete the coarse alignment; In module M2: keep the horizontal pointing angle of the data transmission satellite antenna unchanged, rotate the pointing angle in the pitch direction, and record the angle corresponding to the extreme value of the ground receiving signal power of the ground receiving antenna during the rotation of the data transmission satellite antenna, so as to determine and complete the pitch direction alignment. The range of rotation of the data transmission satellite antenna in the elevation direction (+θ) Ymax ,-θ Ymax Within the range, a scan is performed from +Y to -Y with an elevation step angle Δθ1. During the scan, the change in the ground received radio frequency signal power of the ground receiving antenna is monitored, and two signal power minima are recorded, denoted as W. Y1 W Y2 The pointing angles in the pitch direction corresponding to the two minimum values ​​are denoted as θ. Y1 θ Y2 θ Y =(θ Y1 +θ Y2 ) / 2, θ Y This refers to the elevation angle when the ground receiving antenna and the data transmission satellite antenna are aligned.

[0052] In module M3: Keeping the pointing angle of the data transmission satellite antenna in the elevation direction unchanged, rotate the pointing angle of the data transmission satellite antenna in the horizontal direction, and record the angle corresponding to the extreme value of the ground received signal power during the rotation of the data transmission satellite antenna, so as to determine and complete the horizontal alignment. The data transmission satellite antenna is in the horizontal direction within the antenna rotation range (+θ) Xmax ,-θ Xmax Within the range, a rapid scan is performed from +X to -X with a horizontal step angle Δθ2. During the scan, the change in the ground-received radio frequency signal power of the ground receiving antenna is monitored, and two signal power minimum values ​​W are recorded. X1 W X2 The horizontal pointing angles corresponding to the two minimum values ​​are θ and θ, respectively. X1 θ X2 θ X =(θ X1 +θ X2 ) / 2, θ XThis refers to the horizontal angle when the ground receiving antenna and the data transmission satellite antenna are aligned. Keep the horizontal direction pointing at angle θ X Unchanged, with θ Y Centered on the angle, the antenna rotation step angle is reduced to drive the data transmission satellite antenna, which rotates within a small angle range in the elevation direction, refining the pointing angle in the elevation direction and gradually approaching the elevation angle θ that the ground receiving antenna and the data transmission satellite antenna are aligned with. YO ; Maintain the pointing angle θ in the pitch direction YO Unchanged, with θ X Centered on the angle, the antenna rotation step angle is reduced to drive the data transmission satellite antenna to rotate within a small angle range in the horizontal direction, refining the horizontal pointing angle of the antenna and gradually approaching the horizontal angle θ between the ground receiving antenna and the data transmission satellite antenna. XO .

[0053] In module M4: Given that the distance between the data transmission satellite antenna and the ground receiving antenna is measurable, the antenna gain is determined, the signal received power is measurable, and the space environment loss, antenna pointing loss, and link loss are fixed, the theoretical signal-to-noise ratio of the ground system to which the ground receiving antenna belongs is determined. Compared with the measured signal-to-noise ratio, if the measured signal-to-noise ratio is greater than or equal to the theoretical received signal-to-noise ratio of the ground system... This indicates that the antenna is aligned; if the measured signal-to-noise ratio is less than the theoretical signal-to-noise ratio of the ground system's received signal, then the antenna is aligned. If so, it indicates that the antenna is not aligned; Let the spectrum analyzer of the ground system calibrate the signal output power at the input of the satellite data transmission antenna to be P. t The gain of the data transmission satellite antenna is G. t The isotropic radiated power of the satellite portion for: (1) Signal free space loss between satellite-borne data transmission antenna and ground receiving antenna for: (2) Where d is the propagation distance; The radiation frequency; Theoretical signal-to-noise ratio of ground system received signal for: -K(3) in, This represents the theoretically received useful signal power of the ground system. This represents the theoretical received noise signal power of the ground system. L r Indicates rainfall loss,L a Indicates atmospheric loss. L p Indicates polarization loss. L rp G represents the antenna pointing loss; G / T represents the antenna gain to noise-temperature ratio of the ground receiving system, where G represents the antenna gain of the ground system, T represents the noise-temperature of the ground system, and K is the logarithm of Boltzmann's constant.

[0054] The theoretical signal-to-noise ratio of the ground system when the ground receiving antenna and the data transmission satellite antenna are aligned is obtained based on the RF wired link loss, RF signal free space loss, antenna pointing loss, and the gain of the data transmission satellite antenna and the ground receiving antenna.

[0055] Those skilled in the art will understand that, besides implementing the system and its various devices, modules, and units provided by this invention in the form of purely computer-readable program code, the same functions can be achieved entirely through logical programming of the method steps, making the system and its various devices, modules, and units of this invention function in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, and embedded microcontrollers. Therefore, the system and its various devices, modules, and units provided by this invention can be considered as a hardware component, and the devices, modules, and units included therein for implementing various functions can also be considered as structures within the hardware component; alternatively, the devices, modules, and units for implementing various functions can be considered as both software modules implementing the method and structures within the hardware component.

[0056] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A method for aligning a two-dimensional point-beam data transmission satellite antenna in wireless docking, characterized in that, include: Step S1: Perform coarse alignment of the ground receiving antenna and the data transmission satellite antenna; Step S2: Align the data transmission satellite antenna in the elevation direction; Step S3: Align the data transmission satellite antenna horizontally; Step S4: Verify the signal-to-noise ratio of the received signal from the ground receiving antenna corresponding to the data transmission satellite antenna. If the verification is successful, the data transmission satellite antenna and the ground receiving antenna are considered to be aligned. If the verification fails, step S2 is triggered to continue execution.

2. The method for aligning a two-dimensional point-beam data transmission satellite antenna in wireless docking according to claim 1, characterized in that, In step S1: the ground receiving antenna is rotated to the direction of the data transmission satellite antenna, and it is ensured that there are no buildings obstructing the wireless communication link to complete the coarse alignment; In step S2: Keep the horizontal pointing angle of the data transmission satellite antenna unchanged, rotate the pointing angle in the pitch direction, and record the angle corresponding to the extreme value of the ground receiving signal power of the ground receiving antenna during the rotation of the data transmission satellite antenna, so as to determine and complete the pitch direction alignment. The range of rotation of the data transmission satellite antenna in the elevation direction (+θ) Ymax ,-θ Ymax Within the range, a scan is performed from +Y to -Y with an elevation step angle Δθ1. During the scan, the change in the ground received radio frequency signal power of the ground receiving antenna is monitored, and two signal power minima are recorded, denoted as W. Y1 W Y2 The pointing angles in the pitch direction corresponding to the two minimum values ​​are denoted as θ. Y1 θ Y2 θ Y =(θ Y1 +θ Y2 ) / 2, θ Y This refers to the elevation angle when the ground receiving antenna and the data transmission satellite antenna are aligned.

3. The method for aligning a two-dimensional point-beam data transmission satellite antenna in wireless docking according to claim 2, characterized in that, In step S3: Keeping the pointing angle of the data transmission satellite antenna in the elevation direction unchanged, rotate the pointing angle of the data transmission satellite antenna in the horizontal direction, and record the angle corresponding to the extreme value of the ground received signal power during the rotation of the data transmission satellite antenna, so as to determine and complete the horizontal alignment. The data transmission satellite antenna is in the horizontal direction within the antenna rotation range (+θ) Xmax ,-θ Xmax Within the range, a rapid scan is performed from +X to -X with a horizontal step angle Δθ2. During the scan, the change in the ground-received radio frequency signal power of the ground receiving antenna is monitored, and two signal power minimum values ​​W are recorded. X1 W X2 The horizontal pointing angles corresponding to the two minimum values ​​are θ and θ, respectively. X1 θ X2 θ X =(θ X1 +θ X2 ) / 2, θ X This refers to the horizontal angle when the ground receiving antenna and the data transmission satellite antenna are aligned. Keep the horizontal direction pointing at angle θ X Unchanged, with θ Y Centered on the angle, the antenna rotation step angle is reduced to drive the data transmission satellite antenna, which rotates within a small angle range in the elevation direction, refining the pointing angle in the elevation direction and gradually approaching the elevation angle θ that the ground receiving antenna and the data transmission satellite antenna are aligned with. YO ; Maintain the pointing angle θ in the pitch direction YO Unchanged, with θ X Centered on the angle, the antenna rotation step angle is reduced to drive the data transmission satellite antenna to rotate within a small angle range in the horizontal direction, refining the horizontal pointing angle of the antenna and gradually approaching the horizontal angle θ between the ground receiving antenna and the data transmission satellite antenna. XO .

4. The method for aligning a two-dimensional point-beam data transmission satellite antenna in wireless docking according to claim 1, characterized in that, In step S4: Given that the distance between the data transmission satellite antenna and the ground receiving antenna is measurable, the antenna gain is determined, the signal received power is measurable, and the space environment loss, antenna pointing loss, and link loss are fixed, the theoretical signal-to-noise ratio of the ground system to which the ground receiving antenna belongs is determined. Compared with the measured signal-to-noise ratio, if the measured signal-to-noise ratio is greater than or equal to the theoretical received signal-to-noise ratio of the ground system... This indicates that the antenna is aligned; if the measured signal-to-noise ratio is less than the theoretical signal-to-noise ratio of the ground system's received signal, then the antenna is aligned. If so, it indicates that the antenna is not aligned; Let the spectrum analyzer of the ground system calibrate the signal output power at the input of the satellite data transmission antenna to be P. t The gain of the data transmission satellite antenna is G. t The isotropic radiated power of the satellite portion for: (1) Signal free space loss between satellite-borne data transmission antenna and ground receiving antenna for: (2) Where d is the propagation distance; The radiation frequency; Theoretical signal-to-noise ratio of ground system received signal for: -K(3) in, This represents the theoretically received useful signal power of the ground system. This represents the theoretical received noise signal power of the ground system. L r Indicates rainfall loss, L a Indicates atmospheric loss. L p Indicates polarization loss. L rp G represents the antenna pointing loss; G / T represents the antenna gain to noise-temperature ratio of the ground receiving system, where G represents the antenna gain of the ground system, T represents the noise-temperature of the ground system, and K is the logarithm of Boltzmann's constant.

5. The method for aligning a two-dimensional point-beam data transmission satellite antenna in wireless docking according to claim 4, characterized in that, The theoretical signal-to-noise ratio of the ground system when the ground receiving antenna and the data transmission satellite antenna are aligned is obtained based on the RF wired link loss, RF signal free space loss, antenna pointing loss, and the gain of the data transmission satellite antenna and the ground receiving antenna.

6. A two-dimensional spot-beam data transmission satellite antenna alignment system for wireless docking, characterized in that, include: Module M1: Performs coarse alignment of the ground receiving antenna and the data transmission satellite antenna; Module M2: Aligns the data transmission satellite antenna in the elevation direction; Module M3: Horizontally aligns the data transmission satellite antenna; Module M4: Performs signal-to-noise ratio verification on the received signal of the ground receiving antenna corresponding to the data transmission satellite antenna. If the verification passes, the data transmission satellite antenna is considered to be aligned with the ground receiving antenna; if the verification fails, module M2 is triggered to continue execution.

7. The two-dimensional spot-beam data transmission satellite antenna alignment system for wireless docking according to claim 6, characterized in that, In module M1: the ground receiving antenna is rotated to the direction of the data transmission satellite antenna, and it is ensured that there are no buildings obstructing the wireless communication link to complete the coarse alignment; In module M2: keep the horizontal pointing angle of the data transmission satellite antenna unchanged, rotate the pointing angle in the pitch direction, and record the angle corresponding to the extreme value of the ground receiving signal power of the ground receiving antenna during the rotation of the data transmission satellite antenna, so as to determine and complete the pitch direction alignment. The range of rotation of the data transmission satellite antenna in the elevation direction (+θ) Ymax ,-θ Ymax Within the range, a scan is performed from +Y to -Y with an elevation step angle Δθ1. During the scan, the change in the ground received radio frequency signal power of the ground receiving antenna is monitored, and two signal power minima are recorded, denoted as W. Y1 W Y2 The pointing angles in the pitch direction corresponding to the two minimum values ​​are denoted as θ. Y1 θ Y2 θ Y =(θ Y1 +θ Y2 ) / 2, θ Y This refers to the elevation angle when the ground receiving antenna and the data transmission satellite antenna are aligned.

8. The two-dimensional spot beam data transmission satellite antenna alignment system for wireless docking according to claim 7, characterized in that, In module M3: Keeping the pointing angle of the data transmission satellite antenna in the elevation direction unchanged, rotate the pointing angle of the data transmission satellite antenna in the horizontal direction, and record the angle corresponding to the extreme value of the ground received signal power during the rotation of the data transmission satellite antenna, so as to determine and complete the horizontal alignment. The data transmission satellite antenna is in the horizontal direction within the antenna rotation range (+θ) Xmax ,-θ Xmax Within the range, a rapid scan is performed from +X to -X with a horizontal step angle Δθ2. During the scan, the change in the ground-received radio frequency signal power of the ground receiving antenna is monitored, and two signal power minimum values ​​W are recorded. X1 W X2 The horizontal pointing angles corresponding to the two minimum values ​​are θ and θ, respectively. X1 θ X2 θ X =(θ X1 +θ X2 ) / 2, θ X This refers to the horizontal angle when the ground receiving antenna and the data transmission satellite antenna are aligned. Keep the horizontal direction pointing at angle θ X Unchanged, with θ Y Centered on the angle, the antenna rotation step angle is reduced to drive the data transmission satellite antenna, which rotates within a small angle range in the elevation direction, refining the pointing angle in the elevation direction and gradually approaching the elevation angle θ that the ground receiving antenna and the data transmission satellite antenna are aligned with. YO ; Maintain the pointing angle θ in the pitch direction YO Unchanged, with θ X Centered on the angle, the antenna rotation step angle is reduced to drive the data transmission satellite antenna to rotate within a small angle range in the horizontal direction, refining the horizontal pointing angle of the antenna and gradually approaching the horizontal angle θ between the ground receiving antenna and the data transmission satellite antenna. XO .

9. The two-dimensional spot-beam data transmission satellite antenna alignment system for wireless docking according to claim 6, characterized in that, In module M4: Given that the distance between the data transmission satellite antenna and the ground receiving antenna is measurable, the antenna gain is determined, the signal received power is measurable, and the space environment loss, antenna pointing loss, and link loss are fixed, the theoretical signal-to-noise ratio of the ground system to which the ground receiving antenna belongs is determined. Compared with the measured signal-to-noise ratio, if the measured signal-to-noise ratio is greater than or equal to the theoretical received signal-to-noise ratio of the ground system... This indicates that the antenna is aligned; if the measured signal-to-noise ratio is less than the theoretical signal-to-noise ratio of the ground system's received signal, then the antenna is aligned. If so, it indicates that the antenna is not aligned; Let the spectrum analyzer of the ground system calibrate the signal output power at the input of the satellite data transmission antenna to be P. t The gain of the data transmission satellite antenna is G. t The isotropic radiated power of the satellite portion for: (1) Signal free space loss between satellite-borne data transmission antenna and ground receiving antenna for: (2) Where d is the propagation distance; The radiation frequency; Theoretical signal-to-noise ratio of ground system received signal for: -K(3) in, This represents the theoretically received useful signal power of the ground system. This represents the theoretical received noise signal power of the ground system. L r Indicates rainfall loss, L a Indicates atmospheric loss. L p Indicates polarization loss. L rp G represents the antenna pointing loss; G / T represents the antenna gain to noise-temperature ratio of the ground receiving system, where G represents the antenna gain of the ground system, T represents the noise-temperature of the ground system, and K is the logarithm of Boltzmann's constant.

10. The two-dimensional spot beam data transmission satellite antenna alignment system for wireless docking according to claim 9, characterized in that, The theoretical signal-to-noise ratio of the ground system when the ground receiving antenna and the data transmission satellite antenna are aligned is obtained based on the RF wired link loss, RF signal free space loss, antenna pointing loss, and the gain of the data transmission satellite antenna and the ground receiving antenna.

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