XY seat frame antenna gain test method and related equipment

Abstract

The invention discloses an XY seat frame antenna gain test method and related equipment. The method comprises the following steps: selecting any geosynchronous orbit satellite in the field of view of an antenna as a beacon source, and enabling the optical axis of the antenna to point to the geosynchronous orbit satellite; reading and recording the rotation angle of the X-axis motor and the rotation angle of the Y-axis motor at the moment when the peak searching of the signal level received by the frequency spectrograph reaches the maximum value, and taking the rotation angle of the Y-axis motor as a projection deflection angle; under the condition that the projection deflection angle is kept unchanged, single-degree-of-freedom scanning is executed to obtain the angle difference of the relative accurate star pointing positions of the X-axis motor and the Y-axis motor; and constructing a space geometric projection relation based on the projection deflection angle, executing space projection correction on the obtained angle difference of the X-axis motor, and calculating a real antenna beam width in combination with the angle difference of the Y-axis motor so as to carry out gain test. The problem that the antenna gain test is inaccurate due to the fact that physical alignment is tedious and an AZ-EL correction formula is misused in the existing test can be solved.

Description

Technical Field

[0001] This application relates to the aerospace field, and more specifically, to a method and related equipment for testing the gain of an XY mount antenna. Background Technology

[0002] With the development of satellite communication technology, portable satellite tracking and control stations are increasingly widely used in emergency communication, field tracking and control, and other fields. In order to meet the requirements of system portability, no overhead blind spots, and adaptability to low-Earth orbit satellite tracking, the antenna mount type is gradually changing from the traditional azimuth-elevation (AZ-EL) type to the XY type.

[0003] After the ground station is erected, in-situ performance testing of the antenna is typically performed using the satellite beacon method. This mainly involves obtaining the beamwidth by scanning the antenna pattern, and then using the lobe method to invert and calculate the antenna gain. This is a crucial step in evaluating whether the antenna performance is up to standard. For beamwidth measurement and gain calculation of XY mount antennas in field environments, there are currently two main methods: the orthogonal method and applying the AE formula. The orthogonal method requires not only that the XY mount be strictly north-pointing, but also that it be pointed at a geostationary satellite at a specific longitude, usually a geostationary satellite near the station, thus limiting the selection of the station location. While applying the AE formula to XY mount antennas can sometimes improve antenna gain test results by mistakenly using the AZ-EL correction formula, the underlying principle is clearly flawed. Summary of the Invention

[0004] The summary section introduces a series of simplified concepts, which will be further explained in detail in the detailed description section. This summary section is not intended to limit the key features and essential technical features of the claimed technical solution, nor is it intended to determine the scope of protection of the claimed technical solution.

[0005] To address the problems of cumbersome physical alignment and inaccurate antenna gain testing due to misuse of the AZ-EL correction formula in existing XY mount field antenna pattern testing, this invention proposes an XY mount antenna gain testing method for a portable XY mount reflector antenna system. The XY mount includes an X-axis motor and a Y-axis motor mounted on top of the X-axis motor. The method includes: After completing antenna initialization, select any geostationary orbit satellite within the antenna's field of view as a beacon source, and point the antenna's line of sight towards the geostationary orbit satellite; When the peak value of the signal level received by the spectrum analyzer reaches the maximum value, the rotation angle of the X-axis motor and the rotation angle of the Y-axis motor are read and recorded at this time. The rotation angle of the Y-axis motor is used as the projection angle. Under the condition of keeping the projection angle unchanged, single-degree-of-freedom scanning is performed to obtain the angle difference between the X-axis motor and the Y-axis motor relative to the precise star pointing position. Based on the projection angle, a spatial geometric projection relationship is constructed. Spatial projection correction is performed on the obtained angle difference of the X-axis motor. Combined with the angle difference of the Y-axis motor, the actual antenna beamwidth is calculated for gain testing.

[0006] Secondly, the present invention also proposes an XY mount antenna gain testing device for a portable XY mount reflector antenna system. The XY mount includes an X-axis motor and a Y-axis motor mounted on the X-axis motor. The device includes: The selection unit is used to select any geostationary orbit satellite within the antenna's field of view as a beacon source after antenna initialization is completed, so that the antenna's line of sight points to the geostationary orbit satellite. The scanning unit is used to read and record the rotation angles of the X-axis motor and the Y-axis motor when the peak value of the signal level received by the spectrum analyzer reaches the maximum value. The rotation angle of the Y-axis motor is used as the projection angle. Under the condition of keeping the projection angle unchanged, single-degree-of-freedom scanning is performed to obtain the angle difference between the X-axis motor and the Y-axis motor relative to the precise star pointing position. The correction unit is used to construct a spatial geometric projection relationship based on the projection angle, perform spatial projection correction on the obtained angle difference of the X-axis motor, and combine it with the angle difference of the Y-axis motor to calculate the actual antenna beamwidth for gain testing.

[0007] Thirdly, an electronic device includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program stored in the memory to implement the steps of the XY mount antenna gain testing method as described in any of the first aspects above.

[0008] Fourthly, the present invention also proposes a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the XY mount antenna gain testing method of any of the above claims in the first aspect.

[0009] In summary, the XY mount antenna gain testing method proposed in this application involves selecting any geostationary orbit satellite within the antenna's field of view as a beacon source after antenna initialization, and pointing the antenna's line of sight towards the geostationary orbit satellite. When the peak value of the received signal level by the spectrum analyzer reaches its maximum, the rotation angles of the X-axis motor and the Y-axis motor are read and recorded. The rotation angle of the Y-axis motor is used as the projection deflection angle. While keeping the projection deflection angle constant, single-degree-of-freedom scans are performed to obtain the angular difference between the X-axis motor and the Y-axis motor relative to the precise satellite pointing position. Based on the projection deflection angle, a spatial geometric projection relationship is constructed, and spatial projection correction is performed on the obtained angle difference of the X-axis motor. Combined with the angle difference of the Y-axis motor, the actual antenna beamwidth is calculated for gain testing. Therefore, only a horizontal X-axis rotation axis is required, without requiring the X-axis to face a specific direction, reducing steps such as compass calibration and physical turntable alignment, making it suitable for emergency and rapid field setup. The ability to select any geostationary orbit satellite within the antenna's field of view as a beacon source eliminates the limitation of specific satellite longitudes near the station, reducing site selection constraints. Using the projection deflection angle as the sole geometric constraint factor, the angular difference of non-orthogonal tangential scanning is converted into orthogonal equivalent angular difference through spatial projection, restoring the true beamwidth and ensuring that the gain estimation is based on correct physical quantities. The entire process relies on recordable motor angle logs and spectrum analyzer level curves, and the parameters are verifiable, facilitating the generation of field acceptance reports and historical comparisons. Correction relationships can be implemented using lookup tables, adapting to low-computing-power controllers. Furthermore, the scanning process is a one-dimensional step control, with a simple control strategy and strong field operability. Attached Figure Description

[0010] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit this specification. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 A schematic flowchart of an XY mount antenna gain testing method provided in this application embodiment; Figure 1a This is a spatial geometric projection schematic diagram of an XY mount antenna gain testing method provided in an embodiment of this application; Figure 2 A schematic diagram of an XY mount antenna gain testing device provided in this application embodiment; Figure 3 This is a schematic diagram of an electronic device for testing the gain of an XY mount antenna, provided as an embodiment of this application. Detailed Implementation

[0011] The terms "first," "second," "third," "fourth," etc. (if present) in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus. The technical solutions of the embodiments of this application will now be clearly and completely described in conjunction with the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them.

[0012] To address the issues of cumbersome physical alignment and inaccurate antenna gain measurements due to misuse of the AZ-EL correction formula during existing XY mount field antenna pattern testing, please refer to... Figure 1 , Figure 1 This is a schematic flowchart of an XY mount antenna gain testing method provided in an embodiment of this application. The XY mount antenna gain testing method is applied to a portable XY mount reflector antenna system. The XY mount includes an X-axis motor and a Y-axis motor mounted on the X-axis motor. Specifically, it may include steps S110 to S130.

[0013] S110: After completing antenna initialization, select any geostationary orbit satellite within the antenna's field of view as a beacon source, and point the antenna's line of sight toward the geostationary orbit satellite.

[0014] S120, when the peak value of the signal level received by the spectrum analyzer reaches the maximum value, read and record the rotation angle of the X-axis motor and the rotation angle of the Y-axis motor at this time, take the rotation angle of the Y-axis motor as the projection angle, and perform single-degree-of-freedom scanning respectively while keeping the projection angle unchanged to obtain the angle difference between the X-axis motor and the Y-axis motor relative to the precise star pointing position.

[0015] S130, Based on the projection angle, construct a spatial geometric projection relationship, perform spatial projection correction on the obtained angle difference of the X-axis motor, and combine it with the angle difference of the Y-axis motor to calculate the actual antenna beamwidth for gain testing.

[0016] Understandably, in AZ-EL mounts, the rotation planes for azimuth and elevation are clearly related to the great circles of latitude and longitude on the celestial sphere. Conventional scanning is equivalent to angular deflection along an orthogonal tangent plane passing through the beam center. Therefore, the relationship between the angle the motor rotates and the angle the antenna's line of sight deflects on the celestial sphere is very intuitive under normal conditions. However, in XY mounts, especially in portable field deployments where the base is often positioned according to terrain and the X-axis orientation is random, the rotation plane of the X-axis motor may not be orthogonal to the line-of-sight direction pointing to the satellite. In this case, rotating the X-axis motor by a small angle may appear as a slight rotation, but the antenna's line-of-sight deflection on the celestial sphere does not occur along the tangent of the great circle passing through the beam center, but rather more like a deflection along a non-orthogonal tangent plane. The 3-decibel and 10-decibel angle differences obtained using X-axis scanning are often large, and the error varies significantly with the base's orientation and the selected satellite azimuth. The gain measured by the same antenna in different locations exhibits unstable drift. Defining the Y-axis motor angle in precise star pointing mode as the projection deflection angle essentially utilizes the structural characteristics of the XY mount to extract a measurement of the degree of non-orthogonality. In a typical XY mount structure, the Y-axis motor is mounted on top of the X-axis motor, and the Y-axis rotation plane is driven along with the X-axis attitude. In precise star pointing mode, the Y-axis motor rotates to a certain angle, ensuring the line of sight accurately points to the satellite. This angle effectively reflects the projection relationship of the line-of-sight direction onto the normal of the X-axis rotation plane, that is, the degree of deviation between the X-axis scanning plane and the satellite's line-of-sight direction from orthogonality. In other words, the projection deflection angle is not an arbitrary angle, but rather a measure of how much it deviates from the orthogonal scanning condition using a repeatable electromechanical quantity. Due to the strong kinematic constraints of the XY mount, under a given structure and precise star pointing mode, the mapping between the X-axis scanning trajectory and the actual celestial sphere offset is reduced to only one degree of geometric difference, thus requiring only a single factor for correction. The real goal of constructing spatial geometric projection relationships is to measure the angular response near the beam center, specifically how much the line-of-sight deflects on the orthogonal tangent plane causes the signal to drop by 3 dB or 10 dB. However, when the X-axis motor scans downwards in any direction, the line-of-sight deflection occurs along a slanted path. There is a projection ratio between the angular step on the slanted path and the equivalent angular step on the orthogonal tangent plane, determined by the projection deflection angle. Therefore, multiplying the angular difference measured on the X-axis by a correction factor determined by the projection deflection angle yields the true angular difference equivalent to orthogonal scanning, thus restoring the true beamwidth. When the beamwidth is small, with the main lobe of common parabolic antennas typically in the order of metric degrees or even smaller, this projection relationship can be expressed in a very stable linear form, with low engineering implementation burden and insensitivity to noise.

[0017] For example, when deploying a portable XY-mounted reflector antenna in the field, the operator first completes antenna initialization. This involves setting up the base in an open area and adjusting it with an electronic level to ensure the X-axis motor's rotation axis is horizontal relative to gravity, allowing the base to be placed arbitrarily in the horizontal plane without requiring the X-axis to face a specific direction. Then, the operator obtains the station's longitude and latitude using the system's built-in GNSS module and sets the antenna control system to a directional control state. After initialization, the operator selects any geostationary orbit satellite within the antenna's line of sight as a beacon source, prioritizing beacon frequencies with high signal-to-noise ratios and low interference from nearby satellites to improve the stability of subsequent signal level determination. Next, based on the station's longitude and latitude and the target satellite's longitude, the operator calculates the target drive angles for the X and Y-axis motors using any coordinate transformation and inverse kinematics of the mount. This drives the two motors to roughly point the antenna's line of sight towards the target satellite, and the pointing is fine-tuned under the real-time signal level display of the spectrum analyzer until the received signal level approaches its peak value. By leveraging the near-stable angular position of geostationary satellites during the testing period, the reference beacon source for pattern scanning can be kept constant. This limits measurement uncertainty primarily to the mapping between the mount geometry and motor angles, rather than the satellite motion itself. Consequently, the station can enter a measurable state without strict north alignment or pointing towards a satellite at a specific longitude nearby. This is particularly beneficial in scenarios where the mount orientation is limited, such as mountainous areas, vehicle-mounted locations, or emergency sites, enabling rapid satellite pointing preparation and significantly reducing preparation time caused by physical alignment. Furthermore, it provides a repeatable and accurate satellite pointing reference for subsequent projection deflection acquisition.

[0018] For example, once the antenna line of sight is pointed at the target geosynchronous orbit satellite, the operator uses a spectrum analyzer to finely target the beacon level. This involves first fine-tuning the X-axis motor with small steps, then fine-tuning the Y-axis motor with small steps, and combining this with peak hold or real-time curve observation to ensure the received signal level reaches its maximum value and remains within a stable range. At this point, the encoder angle logs of the X-axis and Y-axis motors are read and recorded. The rotation angle of the Y-axis motor at this moment is defined as the projected deflection angle, and during subsequent X-axis scans, the Y-axis angle is maintained constant through servo position hold to fix the degree of non-orthogonality of the X-axis rotation plane relative to the line-of-sight vector. Subsequently, two single-degree-of-freedom scans are performed to obtain the angle difference between the two axes relative to the precise satellite pointing position: during the first scan, the Y-axis motor is locked, and only the X-axis motor is driven to gradually deviate from the satellite pointing direction with a preset small step angle. The spectrum analyzer continuously monitors the level, and when the level relative to the peak value drops to 3 dB and 10 dB respectively, the angle difference between the X-axis motor and the precise satellite pointing position is recorded. To enhance the stability of the judgment, a moving average or median filter can be applied to the level sequence to avoid transient false triggering caused by wind load jitter and short-term multipath propagation. During the second scan, the system returns to the precise star-pointing position and locks the X-axis motor. Only the Y-axis motor is driven to scan with the same small step angle. The angle difference of the Y-axis motor is recorded when the level drops to 3 decibels and 10 decibels respectively. The projection deflection angle, as the only geometric constraint, characterizes the degree of deviation of the X-axis scan path from the great circle section scan passing through the line of sight under the current random base orientation. As long as this deflection angle remains constant during the scan, the mapping relationship between the X-axis scan angle and the equivalent deflection angle of the celestial sphere remains unchanged, thus allowing for consistent analytical correction of the X-axis angle difference in subsequent scans. In this way, the original orientation pattern measurement, which required two-dimensional linkage scanning and high operator experience, is decomposed into two easily executed and easily verified one-dimensional scans. By maintaining the projection deflection angle, the geometric uncertainty brought about by random orientation is parameterized and solidified, making the angle difference records at 3 decibel and 10 decibel points more repeatable. Especially under conditions of tight field operation time and limited equipment computing resources, a stable dataset that can be used for gain inversion can still be obtained.

[0019] For example, after obtaining the angular difference data between the X-axis and Y-axis, the controller or host computer establishes a spatial geometric projection relationship using the projection deflection angle as input, and performs spatial projection correction on the X-axis angular difference. In engineering implementation, the correction coefficient can be calculated in real time in the controller, or a table of correction coefficients corresponding to different projection deflection angles can be generated in advance and read from the table during testing to adapt to low computing power environments. The goal of the correction is to convert the oblique scanning angular difference caused by the non-orthogonality between the X-axis rotation plane and the line-of-sight vector into an equivalent angular difference obtained by scanning in a great circle tangent plane orthogonal to the line-of-sight axis, so that the corrected X-axis angular difference and the Y-axis angular difference together constitute the two-dimensional beamwidth parameter of the true radiation pattern. Subsequently, using the corrected X-axis angular difference and the uncorrected or structurally-condition-processed Y-axis angular difference, the true beamwidths at 3 dB and 10 dB are calculated respectively, and substituted into the lobe method or equivalent gain inversion formula to obtain the antenna gain. To improve robustness, two sets of gain estimates can be output simultaneously, and the final test results can be given by averaging or weighting. Simultaneously, the projection deflection angle, the angular difference before and after correction, and the level value at the judgment time are recorded for traceability. For small-angle main lobe scanning, there is a definite projection relationship between the angular displacement on the non-orthogonal tangent plane and the equivalent angular displacement on the orthogonal tangent plane. This projection relationship is uniquely determined by the projection deflection angle. Therefore, through geometric projection correction, the true beamwidth can be recovered without changing the mechanical placement or introducing additional external alignment tools. As a result, the consistency of gain test results for the same antenna is significantly improved under different sites, different bases, random orientations, and even different geostationary orbit satellite orientations. This avoids the common phenomenon of the X-axis beamwidth being too large, leading to low gain or drift with orientation, which is common when the antenna is not corrected. At the same time, the dependence of the traditional orthogonal method on strict north and specific satellites is transformed into a calculable constraint on the projection deflection angle and angle difference log, thereby improving the availability and measurement reliability in field acceptance, emergency maintenance, and rapid calibration scenarios.

[0020] In some examples, the antenna initialization includes: The longitude and latitude of the station are obtained through the GNSS module of the antenna system; Adjust the X-axis motor and the Y-axis motor so that the main lobe of the antenna points to the zenith, initialize the rotation angle of the X-axis motor and the Y-axis motor to 0° respectively, and keep the rotation axis of the X-axis motor horizontal relative to the ground.

[0021] In some examples, selecting any geostationary orbit satellite within the antenna's field of view as a beacon source after antenna initialization, and pointing the antenna's line of sight towards the geostationary orbit satellite, includes: After completing antenna initialization, select any geostationary orbit satellite within the antenna's field of view as a beacon source. Based on the station's longitude and latitude and the geostationary orbit satellite's longitude, calculate the driving angle through coordinate transformation and drive the X-axis motor and Y-axis motor to move, so that the antenna's line of sight points to the geostationary orbit satellite.

[0022] In some examples, performing single-degree-of-freedom scans to obtain the angular difference between the X-axis and Y-axis motors relative to the precise star pointer positions while keeping the projection angle constant includes: While keeping the projection angle unchanged, the Y-axis motor is locked, and only the X-axis motor is driven to scan in its rotation plane, so that the antenna main lobe deviates from the direction of the geosynchronous orbit satellite; When the signal level received by the spectrum analyzer drops by a preset first decibel and a preset second decibel relative to the peak value, the angle difference between the X-axis motor and the precise star pointer position is recorded respectively. Lock the X-axis motor and drive only the Y-axis motor to scan within its rotation plane, causing the antenna main lobe to deviate from the direction of the geosynchronous orbit satellite; When the signal level received by the spectrum analyzer drops by a preset first decibel and a preset second decibel relative to the peak value, the angle difference between the Y-axis motor and the precise star pointer position is recorded respectively.

[0023] For example, in precise satellite pointing mode, the controller holds the Y-axis motor at the position corresponding to the projected deflection angle and enters a position holding mode to prevent the Y-axis angle from drifting during scanning due to load disturbances, hysteresis, or servo following errors. Under this condition, the Y-axis motor is locked, and only the X-axis motor's motion permission is released. The X-axis motor is then driven to scan along its rotation plane at a preset small step angular velocity, causing the antenna main lobe to gradually deviate from the direction pointing towards the geostationary orbit satellite. In this method, the projected deflection angle is used to characterize the degree of non-orthogonality between the X-axis rotation plane and the satellite's line-of-sight direction. Only by keeping the projected deflection angle constant during scanning can the geometric conditions in the subsequent spatial geometric projection relationship be fixed, thus making the correction coefficient corresponding to the same projected deflection angle effective for the entire scan. At the same time, by restricting the system's degrees of freedom to only X-axis motion, the antenna's line-of-sight deviation path can be completely determined by the X-axis rotation angle, avoiding the uncertainty of the deviation trajectory caused by two-dimensional linkage. Without needing to point the base to a specific direction or use a compass or external alignment tools, repeatable and traceable X-axis scan level curves and angle logs can still be obtained. This is especially suitable for situations where the field site is narrow and the base can only be placed according to the terrain, such as at mountain stations or vehicle-mounted temporary parking points. The operator only needs to complete the precise star pointing and lock the Y-axis to start scanning, which significantly reduces the complexity of test preparation and execution.

[0024] For example, during a scan driven solely by the X-axis motor, the spectrum analyzer continuously outputs the received level value at the target beacon frequency. The controller or host computer compares this level with the peak level under precise star pointing conditions. Recording is triggered when the received level drops to a preset first decibel and a preset second decibel relative to the peak, respectively. The encoder angle of the X-axis motor at this moment is saved, and the angle difference relative to the precise star pointing position is calculated. To ensure the stability of the decibel determination, a minimum duration condition can be introduced into the recording logic. For example, the level can be required to remain near a threshold for several sampling periods before confirming that the threshold has been reached. Moving averages or median filtering can be applied to the level sequence to suppress short-term fluctuations caused by wind-induced jitter, slight vehicle shaking, and near-field reflections. The amplitude of the main lobe pattern exhibits a monotonically decreasing range with angular deviation. Within this range, a fixed decibel decrease point can be used as a criterion to correspond to the characteristic angular width of the pattern, thus forming a measurable angular difference directly related to the antenna beamwidth. Simultaneously, recording two different decibel points allows sampling at the near end and outermost regions of the main lobe, making subsequent gain inversion less sensitive to pattern shape deviations. Without needing to perform high-density angle-scan fitting on the complete radiation pattern, key measurements for beamwidth and gain calculations can be quickly obtained simply by measuring the angle difference to the preset decibel drop point. This shortens measurement time and maintains usability even when the beacon signal-to-noise ratio fluctuates. For example, in strong signal scenarios, 3 dB and 10 dB can be used simultaneously as the first and second dB to improve gain estimation accuracy, while in weak or interference-prone scenarios, the second dB can be set to a smaller drop to ensure reliable judgment, thus maintaining a consistent measurement process.

[0025] For example, after completing the threshold recording for the X-axis scan, the system restores the antenna to the precise star-pointing position and switches the scanning degrees of freedom: the controller locks the X-axis motor, fixing its angle at the angle position corresponding to the precise star-pointing state, thereby fixing the attitude of the X-axis rotation plane relative to the Earth coordinates and the satellite direction; under the condition of X-axis locking, only the Y-axis motor is released, driving the Y-axis motor to perform small-step scans along its rotation plane, causing the antenna main lobe to gradually deviate from pointing towards the geosynchronous orbit satellite. In a typical XY mount structure, the Y-axis motor, as the upper-level carried axis, has its rotation plane stably passing through the antenna's line of sight when the X-axis is locked. Therefore, the Y-axis scan is closer to deflecting the line of sight within the tangent plane passing through the beam center, providing another measurement reference for the two-dimensional beamwidth; at the same time, locking the X-axis can avoid passive drift of the X-axis due to gravitational imbalance, hysteresis, or external disturbances during the Y-axis scan, ensuring a stable relationship between the Y-axis scan angle and the line of sight deflection. By breaking down the two-dimensional orientation pattern measurement into two one-dimensional scans, first X and then Y, the on-site operator can obtain the angular width data in both directions without simultaneously controlling the linkage of the two axes, reducing operational errors and improving the consistency of retests. For example, in emergency support tasks where personnel lack experience, the measurement can be completed by locking and scanning the axes according to a fixed procedure, and the sensitivity of the test results to differences in operator technique is significantly reduced.

[0026] For example, during a scan driven solely by the Y-axis motor, the spectrum analyzer continuously monitors the received level of the target beacon frequency and compares it with the peak level under precise star pointing conditions. When the received level drops to a preset first decibel and a preset second decibel relative to the peak, the controller records the Y-axis motor encoder angle at that moment and calculates the angle difference relative to the precise star pointing position. Simultaneously, the same stabilization strategy as for the X-axis can be employed, such as level threshold maintenance, anti-jitter filtering, and rules for eliminating abnormally abrupt sample changes. Under X-axis locking conditions, the angle difference obtained from the Y-axis scan is closer to the true main lobe angular width. This, together with the projected X-axis equivalent angle difference, constitutes a two-dimensional angular width parameter for beamwidth calculation, thus providing reliable input for beamwidth gain inversion. Furthermore, simultaneously acquiring the Y-axis angular difference at two decibel drop points allows for a correspondence with the two sets of X-axis angular differences, enabling gain calculation to utilize multi-point information to reduce the impact of occasional measurement errors. On the one hand, the Y-axis angular difference can serve as the true measurement dimension paired with the X-axis correction result, so that the final beamwidth and gain results no longer depend on the base pointing or external mechanical alignment. On the other hand, by pairing the same decibel point, the system can simultaneously provide two sets of beamwidth and gain estimates when outputting the test report, which is convenient for evaluating measurement stability and anomaly diagnosis. For example, when the 3-decibel result is stable but the 10-decibel result is abnormal, it can indicate the presence of sidelobe interference or near-field reflection, thereby guiding the operator to reselect the star, adjust the site, or change the scanning step strategy, thus improving the engineering usability of the test.

[0027] In some examples, the process of constructing a spatial geometric projection relationship based on the projection angle, performing spatial projection correction on the obtained angle difference of the X-axis motor, and combining it with the angle difference of the Y-axis motor to calculate the actual antenna beamwidth for gain testing includes: Based on the projection angle, a spatial geometric projection relationship is constructed, and spatial projection correction is performed on the obtained angle difference of the X-axis motor to obtain the corrected equivalent beam angle difference, which is equivalent to the angle difference obtained by scanning in a great circle tangent orthogonal to the line of sight. Based on the obtained angle difference of the Y-axis motor and the corrected angle difference of the X-axis motor, the main lobe beamwidth of the antenna at the preset first decibel and preset second decibel is calculated. The antenna gain is calculated based on the beamwidth using the beam lobe method.

[0028] For example, after obtaining the projection deflection angle under precise star pointing state and the angle difference between the X-axis scan at the preset first decibel and preset second decibel, the controller or host computer uses the projection deflection angle as a geometric constraint input to establish a spatial geometric projection relationship from the X-axis motor rotation angle to the equivalent deflection angle of the line of sight on the celestial sphere, and performs spatial projection correction on the X-axis angle difference accordingly to obtain the corrected equivalent beam angle difference. In engineering implementation, trigonometric function calculations can be completed inside the controller, or the results can be written back after completion on the host computer side. When the controller's computing power is limited, the correction coefficient table under different projection deflection angles can be pre-calculated offline and read from the table during testing, thereby reducing the real-time calculation load. When the X-axis rotation plane is not orthogonal to the satellite's line-of-sight direction, the offset path formed by the X-axis on the celestial sphere due to X-axis scanning does not pass through the orthogonal great circle tangent of the line-of-sight, but is closer to the oblique trajectory on the non-orthogonal tangent plane. Within the small-angle main lobe range, there is a definite projection mapping relationship between the angular displacement corresponding to this oblique trajectory and the equivalent angular displacement in the orthogonal great circle tangent plane. This mapping relationship is uniquely determined by the projection deflection angle. Therefore, by projecting the X-axis angular difference, the equivalent angular difference obtained by scanning in the great circle tangent plane orthogonal to the line-of-sight can be obtained. Therefore, without requiring the base to point north or the X-axis rotation plane to be physically aligned to a specific position beforehand, the X-axis scanning angle difference measured under any orientation can still be uniformly mapped to the same physical meaning of orthogonal scanning angle difference, thereby significantly reducing the drift of test results caused by different placement orientations in different locations. For example, when the same antenna has a large difference in base orientation at two locations due to site limitations, the uncorrected X-axis angle difference often appears to be larger than 3 dB and lowers the gain estimate. However, after projection correction, this larger deviation can be absorbed as a geometric conversion difference, making the equivalent angle difference more consistent with the laboratory calibration.

[0029] For example, after obtaining the corrected equivalent angular difference on the X-axis and the angular difference corresponding to the Y-axis scan, the system calculates the main lobe beamwidth for two criteria: a preset first decibel and a preset second decibel. Specifically, the equivalent angular difference on the X-axis is used as the angular width in an orthogonal principal plane, and the angular difference on the Y-axis is used as the angular width in another orthogonal principal plane. The main lobe beamwidth parameter at that decibel is calculated according to a set of angular differences corresponding to the preset first decibel, and the main lobe beamwidth parameter at that decibel is calculated according to another set of angular differences corresponding to the preset second decibel. In engineering practice, two sets of beamwidths can be output simultaneously to check measurement consistency. For example, when the level at the preset second decibel is close to the noise floor, causing angular difference jitter, the system can prompt the operator to select a stronger beacon source or adjust the step angle and filtering strategy. The main lobe beamwidth is a key quantity describing the angular width of the radiation pattern within two orthogonal tangents. Gain inversion using the lobe method typically requires angular widths in two mutually orthogonal directions as input. However, in an XY mount with arbitrary orientation, directly using the original X-axis angular difference introduces oblique geometric errors. Therefore, the X-axis angular difference must first be corrected to an equivalent angular difference in the sense of orthogonal tangents, and then combined with the Y-axis angular difference to form a two-dimensional representation of the true main lobe beamwidth. By pairing the corrected equivalent X-axis angular difference with the Y-axis angular difference, the beamwidths at the two fractional kilometres no longer depend on the random orientation of the mount and can remain stable during repeated measurements at different locations. For example, in emergency communication support, the same antenna is rapidly deployed at different locations. If the original X-axis angular difference is used directly, the beamwidth will fluctuate with the placement direction. However, after using the equivalent angular difference, the change in beamwidth mainly reflects the antenna's own state, such as feed offset or reflector deformation, rather than the installation orientation, thereby improving the reliability of field acceptance testing.

[0030] For example, after obtaining the main lobe beamwidth at preset first and second decibel levels, the system uses the beamwidth method to calculate the antenna gain. In practice, the angular width parameters at the two preset decibel levels can be substituted into the gain estimation formula of the beamwidth method to obtain two sets of gain estimates. These two sets of gain estimates are then averaged or combined according to empirical weights to reduce the deviation caused by noise, interference, or sidelobe fluctuations in a single decibel criterion. Simultaneously, the system can include the projection angle, original X-axis angular difference, equivalent X-axis angular difference, Y-axis angular difference, and the corresponding level threshold time in the output results to form a traceable gain test report. The beamwidth method essentially utilizes the correspondence between the main lobe beamwidth and the effective aperture of the antenna pattern to convert the measured main lobe beamwidth into an equivalent diameter or equivalent area, and then further derives the gain. When the input beamwidth comes from the corrected orthogonal equivalent angular difference and the angular difference in another orthogonal direction, the physical quantities upon which the gain inversion depends match the theoretical model, thus avoiding mistaking the pedestal geometric slant error as an increase in the antenna main lobe width. On the one hand, the gain test results are significantly less sensitive to the orientation of the site, and can more stably reflect whether the antenna itself is up to standard. On the other hand, by using the angle width at two sets of two decibels to form a dual constraint, the ability to identify abnormal situations can be improved. For example, when the preset second decibel is affected by multipath reflection and causes the level curve to have a shoulder, the difference between the two sets of gain estimates will increase. The system can then prompt the user to reselect the scanning direction, adjust the site, or replace the beacon source, thereby improving the reliability of the measurement results and the operability on site.

[0031] For example, such as Figure 1a As shown, a spatial geometric projection model is constructed. The station is located at point C on the Earth's surface, and point F is a geostationary satellite in geosynchronous orbit. Vector CK is the rotation axis of the X-axis motor, vector CF is the line-of-sight vector between the station and the satellite, and vector CG is the rotation axis of the Y-axis motor. Through X-axis motor scanning, the antenna main lobe changes its pointing direction from point F to point L. ∠CEE', ∠FEE', ∠CEF, and ∠CFL are right angles, and quadrilateral EFLE' is a rectangle. It can be proven that vector CH is perpendicular to vector FL. In the geometric model of this example, the orientation of the X-axis motor's rotation axis (vector CK) is arbitrary, but there is a strict analytical mapping relationship between the X-axis motor's scanning angle (∠ECE') and the antenna beam's scanning angle (∠FCL). Combining the above spatial geometric projection model, through spatial vector dot product operations and spherical trigonometry derivation, it can be proven that this mapping relationship is only related to ∠FCE. ∠FCE = α_y. This invention does not involve complex mathematical proofs, but the simplified (non-approximate) formula for this mapping relationship is as follows, and the original data can be corrected using the following formula: Δβ'_x_3dB=arcsin[sin(Δβ_x_3dB)*cos(α_y)] Δβ'_x_10dB=arcsin[sin(Δβ_x_10dB)*cos(α_y)] Δβ'_x_3dB and Δβ'_x_10dB are the corrected beamwidths, equivalent to the true beamwidth obtained by scanning in the orthogonal plane. In engineering surveying, since the beamwidth is usually a small angle, the above formula can be simplified to a linearly corrected form, thus significantly reducing the computational load. Δβ'_x_3dB≈Δβ_x_3dB*cos(α_y) Δβ'_x_10dB≈Δβ_x_10dB*cos(α_y).

[0032] For example, the antenna gain is calculated using the beamwidth method with two sets of beamwidths, 3 dB and 10 dB, and the gain satisfies the following relationship: Gain = 10 * Log([31000 / (Δβ'_x_3dB*Δβ_y_3dB) + 91000 / (Δβ'_x_10dB*Δβ_y_10dB)] / 2), where Δβ'_x_3dB and Δβ'_x_10dB are the aforementioned corrected equivalent angle differences, and Δβ_y_3dB and Δβ_y_10dB are the aforementioned recorded Y-axis motor angle differences.

[0033] In some examples, it also includes: When the reflector antenna has rotational symmetry, such that the main lobe beamwidths of the antenna are equal in the two mutually orthogonal principal plane directions, after obtaining the projection angle and performing a single degree of freedom scan of the X-axis motor, the single degree of freedom scan of the Y-axis motor is omitted. The X-axis motor angle difference, corrected by spatial projection, is used as the equivalent angle difference in the Y-axis direction to calculate the true antenna beamwidth and perform gain testing.

[0034] For example, when the structure of the antenna under test satisfies rotational symmetry, such as the reflector being an axisymmetric paraboloid and the feed installation and support structure being symmetrically arranged, such that the main lobe beamwidths of the antenna in two mutually orthogonal principal plane directions can be considered equal within the allowable engineering error, the system still obtains the projection deflection angle according to the basic process in the precise star pointing state, and locks the Y-axis motor while keeping the projection deflection angle unchanged, and only drives the X-axis motor to complete a single degree of freedom scan. When the signal level received by the spectrum analyzer drops to the relative peak value to a preset first decibel and a preset second decibel, the angle difference between the X-axis motor and the precise star pointing position is recorded respectively. After completing the X-axis scan, the single degree of freedom scan step of locking the X-axis and driving the Y-axis is no longer executed, and the subsequent angle difference correction and gain inversion calculations are directly entered. For rotationally symmetric antennas, the angular width of the main lobe pattern is consistent across any radial section. The difference in angular width between two orthogonal principal plane directions mainly stems from second-order factors such as manufacturing errors, feed offset, or support obstruction. When the symmetry condition is met and the antenna is in a qualified state, this difference can be ignored within the test accuracy range. Therefore, if the angular difference in one direction has been obtained through X-axis scanning and the non-orthogonal scanning geometry has been corrected through projection offset constraints, the angular width in the other orthogonal direction can be replaced by the same equivalent angular difference without actual scanning. Under the premise of rotational symmetry, pattern testing is simplified from two one-dimensional scans to one one-dimensional scan, reducing on-site testing time and the number of operator steps, and reducing additional error sources introduced by secondary scanning. This is particularly suitable for scenarios requiring rapid inspection of multiple antennas in emergency communication support missions. For example, when multiple deployments and performance verifications need to be completed in a short time at mobile mobile site locations, omitting the Y-axis scan can significantly improve the efficiency of a single test while still maintaining the correct physical meaning of beamwidth and gain measurements under arbitrary deployment conditions.

[0035] For example, in the case of omitting the Y-axis single-degree-of-freedom scan, the system first establishes a spatial geometric projection relationship based on the projection deflection angle, and performs spatial projection correction on the angle difference recorded by the X-axis motor at a preset first decibel and a preset second decibel, to obtain the corrected X-axis equivalent beam angle difference. Subsequently, this equivalent beam angle difference is used simultaneously as the angular width in the X-axis direction and the equivalent angular width in the Y-axis direction. That is, the same set of corrected angular differences replaces the angular differences that should have been obtained by the Y-axis scan, thereby forming the main lobe beamwidth input parameters under two-part decibel criteria. The input parameters are then substituted into the gain calculation formula of the lobe method to obtain the antenna gain. To ensure the engineering reliability of the implementation, the system can provide a symmetry confirmation method before starting this simplified process. For example, the antenna can be marked as rotationally symmetric by the equipment model configuration file, or the E-plane and H-plane angular width consistency threshold can be saved during the initial factory calibration and quickly compared during on-site retesting. When the symmetry condition is not met or deviates from the threshold, the system automatically reverts to the complete two-axis scan process. Gain inversion using the lobe method relies on the main lobe angular widths in two orthogonal directions. When the antenna pattern has rotational symmetry, these two angular widths are theoretically equal. Therefore, using the same equivalent angular difference as the angular width input for both directions does not disrupt the physical model upon which the gain inversion is based. Simultaneously, since the equivalent angular difference has been corrected to an angular difference in the sense of an orthogonal great circle tangent through projection deflection, its physical meaning is consistent with the input quantity of the lobe method, thus avoiding the introduction of mount slant geometry errors into the gain calculation. Therefore, without adding extra hardware or requiring additional alignment, the gain testing process is further compressed, while maintaining adaptability to random mount orientations and consistency of gain results. For example, for portable parabolic antennas with small apertures and good symmetry, under stable beacon source conditions, only one X-axis scan is needed to provide a gain estimate similar to a complete dual-axis scan. This is particularly beneficial in adverse environments such as rain, low temperatures, or high winds, reducing operator exposure time and improving measurement feasibility.

[0036] In some examples, it also includes: In the case where the structure of the XY mount is such that the Y-axis motor is located at the bottom layer and the X-axis motor is mounted on top of the Y-axis motor, when the antenna line of sight is precisely pointed to the geosynchronous orbit satellite and the peak search reaches the maximum value, the rotation angle of the X-axis motor and the rotation angle of the Y-axis motor are read and recorded, and the rotation angle of the X-axis motor is used as the projection deflection angle; While keeping the projection angle constant, a single-degree-of-freedom scan is performed to obtain the angle difference between the Y-axis motor and the precise star pointing position. Based on the projection angle, a spatial geometric projection relationship is constructed, and spatial projection correction is performed on the angle difference of the Y-axis motor. The actual antenna beamwidth is then calculated and the gain is tested in combination with the angle difference of the X-axis motor.

[0037] For example, when the structure of the XY mount is reversed from the common form, i.e., the Y-axis motor is located at the bottom layer and directly connected to the base, and the X-axis motor is mounted on top of the Y-axis motor as the carried axis, after the system completes initialization and points to any geostationary orbit satellite within the antenna's field of view, it still performs detailed peak finding of the beacon level through a spectrum analyzer: the operator fine-tunes the bottom Y-axis and the upper X-axis in small steps to make the received signal level reach its maximum value and remain in a stable range; in this precise satellite pointing state, the controller reads and records the encoder angle logs of the X-axis motor and the Y-axis motor, and defines the rotation angle of the X-axis motor at this time as the projection deflection angle, and writes the projection deflection angle into the parameter storage area required for subsequent scanning and correction calculations. The projection deflection angle needs to reflect the degree of non-orthogonality between the scanning rotation plane of the scanning axis to be projected and the satellite line-of-sight direction. When the mechanism is interchanged, the scanning section properties that originally passed through the line-of-sight direction and the source of oblique scanning error, which were originally borne by the upper axis, will be reversed. In the structure with Y as the bottom layer and X as the top layer, the rotation plane of the bottom Y axis is more likely to be non-orthogonal to the line-of-sight direction, while the pointing angle of the upper X axis more directly represents the geometric deviation of the line-of-sight direction relative to the bottom rotation plane. Therefore, using the X-axis angle under the precise star pointing state as the projection deflection angle can lock the non-orthogonality unique to this structure with a recordable electromechanical quantity. This solution does not require fixed assumptions about the frame structure. Even when the frame assembly method changes or the axis sequence of frames from different manufacturers differs, the correction model can still be maintained by selecting an appropriate projection angle source, thereby expanding the method's compatibility with different XY frame hardware configurations. For example, when the same test software is connected to two frames with different axis sequences in the field, it is only necessary to mark the axis sequence type in the parameter configuration to automatically select the X-axis angle or Y-axis angle as the projection angle and output consistent gain test results, avoiding systematic deviations caused by misusing a fixed formula.

[0038] For example, after determining the X-axis angle as the projection deflection angle, the system keeps this projection deflection angle unchanged in subsequent measurements. The controller enables position holding for the upper X-axis motor, keeping its encoder angle at the angle corresponding to the precise star pointing state, thereby fixing the non-orthogonal geometric conditions. Under this condition, a single-degree-of-freedom scan is performed to obtain the angle difference between the lower Y-axis motor and the precise star pointing position, i.e., locking the upper X-axis motor and driving only the lower Y-axis motor to scan along its rotation plane with a preset small step angle, so that the antenna main lobe gradually deviates from the satellite direction. The angle difference of the Y-axis motor is recorded when the relative peak value of the signal level received by the spectrum analyzer drops to a preset first decibel and a preset second decibel, respectively. At the same time, threshold holding judgment and level sequence filtering can be used to improve the judgment stability. Subsequently, the system constructs a spatial geometric projection relationship based on the projection deflection angle, performs spatial projection correction on the recorded Y-axis angle difference, and obtains the equivalent angle difference corresponding to scanning in a great circle tangent orthogonal to the line of sight. This equivalent angle difference and the angle difference in the X-axis direction are used together to calculate the main lobe beamwidth under the two-decibel criterion, and then the antenna gain is calculated according to the lobe method formula. When the axis order is reversed, the scanning axis that produces the skew error is changed from the original X-axis to the bottom Y-axis. This is because the rotation plane of the bottom axis is more likely to form a non-orthogonal relationship with the satellite line-of-sight direction under random placement and arbitrary orientation. The projection deflection provides the only geometric constraint, which allows the skew scanning angle difference to be deterministically mapped to the equivalent angle difference in the sense of orthogonal tangent. Keeping the projection deflection unchanged ensures that this mapping relationship, which should only be determined by geometry, does not drift throughout the scanning process, thus giving the corrected angle difference a stable physical meaning. Therefore, even with a Y-layer bottom and X-layer top mount structure, the system can still avoid mistaking oblique geometric errors for main lobe widening, thereby improving the accuracy and consistency of beamwidth and gain calculations. For example, in emergency field locations, when the base orientation is random and the ground is uneven, causing significant changes in the force on the mount axis, without projection correction, the gain estimate will drift significantly with the placement orientation. However, by using the X-axis angle as the projection angle and correcting the Y-axis angle difference, the sensitivity of the gain result to the placement orientation is significantly reduced, better reflecting the antenna's true aperture efficiency and assembly status, facilitating on-site qualification judgment and fault diagnosis.

[0039] In some cases, considering the situation in the field, when the antenna main lobe points to the satellite, in addition to the direct wave, there may be reflected waves from reflectors such as the ground, vehicles, containers, and fences. When the reflected waves and direct waves are superimposed at the receiver input, the curve of the received signal level changing with the angle deviating from the main lobe center will no longer be an ideal monotonically decreasing pattern: as the scanning angle gradually deviates, the direct wave decreases according to the antenna pattern, but the reflected waves may be relatively stronger or have more favorable phase superposition in certain angle ranges. Therefore, the signal level curve may show a plateau segment where it stops decreasing after a certain point; or the signal level curve may show a local rebound near a certain angle, forming a shoulder. This type of distortion is not due to a change in the antenna's main lobe width, but rather a superposition effect caused by the propagation environment. If the signal level drops to a preset decibel level as the trigger point, the plateau or shoulder will cause the trigger angle difference to be too small or too large, resulting in a systematic deviation in the main lobe beamwidth and gain inversion. Based on this, some examples also include: When performing the single-degree-of-freedom scan on the X-axis motor or the Y-axis motor, the same motor is scanned in both the forward and reverse directions to obtain two descending curves showing the change in received signal level with angle. The shape consistency of the two descending curves is determined based on the monotonicity, the number of slope changes, or the magnitude of local curvature changes of the descending curves. When it is determined that one of the descending curves has a non-monotonic plateau or shoulder feature, the angle difference corresponding to the other descending curve that meets the monotonic descending condition is used as the angle difference between the preset first decibel and the preset second decibel for subsequent beamwidth calculation and gain testing.

[0040] Understandably, the key to bidirectional scanning is that multipath reflectors are usually distributed on one side or in one direction around the antenna. The level curves of forward and reverse scanning are often affected by multipath to different degrees. Therefore, the abnormal side can be identified by judging the consistency of the two curves, and the side that is closer to the ideal monotonically decreasing side can be selected as the source of reliable angle difference.

[0041] For example, when performing a single-degree-of-freedom scan along the X or Y axis, starting from the precise star pointer angle, the scan proceeds in the positive direction, recording the statistical values ​​of the level sequence at each angular position, such as the median level or fluctuation amplitude during the dwell time. Then, returning to the starting point, the scan proceeds in the reverse direction, recording the same data. The angular positions are mapped to the estimated steady-state levels, constructing both a positive and negative decreasing curve. To avoid transient jitter interference, the median or truncated mean of the level sequence can be used as the estimated steady-state level, and the corresponding fluctuation amplitude is recorded. For each curve, a monotonicity check is performed: whether the level generally decreases along the angular sequence from the center outwards, or whether there are consecutive reverse increases at multiple sampling points; or a slope change complexity check is performed: calculating the level difference between adjacent sampling points and counting the number of sign flips in the difference; excessive flips indicate a shoulder or oscillation in the curve; or a local curvature anomaly check is performed: fitting a local quadratic trend within a sliding window; if a significant local bulge or plateau width exceeds a threshold, it is considered an anomaly; or a fluctuation amplitude check is performed: if the level fluctuation amplitude increases significantly at certain angular positions, it often indicates phase sensitivity caused by multipath interference. When a plateau or shoulder is determined to exist on a curve in a certain direction, the preset first and second decibel trigger points are not extracted on that curve; instead, the trigger point of another curve in the other direction is used as the angular difference of that axis. If an equivalent double-sided angular width is desired, the single-sided angular difference can be used as the equivalent value of the other angular difference, based on the assumption of main lobe approximation symmetry, while only using the single-sided angular difference. The report should indicate that a single-sided reliable curve was used instead. The output should include at least the forward curve, the reverse curve, the anomaly detection result, the direction used, the two-decibel angle difference, and fluctuation amplitude statistics for retesting and on-site adjustments. Thus, after identifying and eliminating the non-monotonic segments caused by multipath propagation, the threshold angle difference is closer to the falling segment of the antenna's true radiation pattern, resulting in a more accurate main lobe beamwidth. In areas where multipath effects are significant, bidirectional optimization can significantly reduce retest dispersion, making the gain measured by the same antenna at different times in the same location more stable. This method does not rely on additional hardware; it improves robustness solely through scanning strategies and curve morphology determination, making it suitable for rapid field testing.

[0042] In some cases, considering that the above scheme uses the projection deflection angle as the sole geometric constraint factor, the implicit premise is that the rotation axis relative to the gravity direction satisfies the expected horizontal constraint, at least approximately during testing. In the field environment, level errors, soft ground settlement, uneven stress on the support feet, and micro-deformation of the structure caused by wind loads can lead to a small tilt component in the bottom rotation axis. The tilt has two consequences: the offset of the line of sight on the celestial sphere is no longer determined solely by the degree of non-orthogonality in the horizontal plane; the tilt introduces an additional geometric projection term, causing a shift in the mapping relationship under the same projection deflection angle; the effect of the tilt may be related to the scanning direction, resulting in a systematic deviation in the equivalent angle difference after projection correction. This tilt is small and difficult to detect in the field, but it can cause considerable errors in narrow-beam measurements with high-gain antennas. Therefore, a method is needed that does not increase north-pointing requirements or introduce complex external angle measuring devices to convert the tilt into an estimable parameter. By artificially applying a set of known small-angle perturbations and observing the regression angle required to return to the peak, the tilt component is encoded into a computable equivalent parameter. Based on this, some examples also include: After obtaining the projection angle, the XY mount is controlled to perform at least one attitude disturbance measurement sequence with a preset amplitude while maintaining the antenna line of sight back to the accurate star pointing state. The change in projection angle before and after the disturbance and the motor angle regression amount required to recover to the peak value of the received signal level are recorded. Based on the change and the regression amount, the equivalent horizontal error parameter of the mount relative to the gravity direction is solved. The equivalent horizontal error parameter is introduced into the spatial geometric projection relationship to compensate for the spatial projection correction, so as to reduce the impact of horizontal error on the beamwidth and gain test results.

[0043] For example, accurate star pointing is performed and the peak level and corresponding motor angle are recorded, along with the projection deflection angle. An axis is selected as the disturbance axis, such as the bottom axis, and a set of preset disturbance angles are applied. The disturbance amplitude should be less than a certain proportion of the main lobe width to avoid excessive deviation that would make peak finding difficult. The disturbance can include both forward and reverse disturbances, returning to near the original angle after each disturbance. After each disturbance, a short peak finding is performed to bring the level back close to the peak, and the regression from the theoretical return angle to the actual peak angle is recorded. This regression reflects the coupling between the geometric error caused by the disturbance and the actual structural tilt. Based on the disturbance amplitude, regression, and change in projection deflection angle, a linearized or nonlinear solution relationship is established to obtain the equivalent horizontal error parameter. In engineering, least squares fitting can be used, with the regression obtained from multiple disturbances as observations to estimate one or two tilt component parameters. When performing spatial projection correction on the angle difference later, this equivalent horizontal error parameter is used as an additional correction term in the mapping, for example, to adjust the projection coefficient or the bias term of the equivalent angle difference. If the fitting residual exceeds a threshold, it indicates that the site or structure is unstable. The system can then prompt for readjustment or a change of site, and revert to a more conservative measurement strategy, such as reducing the use of decibels or shortening the scan time. Thus, by transforming the imperceptible tilt error into an estimable parameter, the applicability of projection correction expands from ideal leveling to allowing for small but compensable tilts, significantly improving field usability. The consistency of repeated measurements of the same antenna under different support conditions, such as soft and hard ground, is improved, and the gain results better reflect the antenna's inherent performance rather than support errors. Furthermore, the fitting residual can be used to generate quantitative diagnostic indicators for site and structural stability.

[0044] In some cases, considering that portable mounts often use reduction mechanisms and gear drives, there is unavoidable mechanical hysteresis and elastic deformation. For example, even if the motor encoder angle is the same, the actual output angle and direction may differ due to different force directions in the transmission chain; or if commutation occurs during scanning, the hysteresis will cause the threshold level trigger point to be inconsistent between the forward and reverse positions. If the first trigger point is still considered as the true angle difference, the angle difference error will directly enter the beamwidth and gain inversion, and the magnitude of the error is related to the commutation strategy and load direction, making it difficult to eliminate by simple averaging. Based on this, some examples also include: During the single-degree-of-freedom scanning process, when the received signal level drops to the preset first decibel or the preset second decibel and triggers the first angle difference recording, the system continues to overshoot the preset angle along the same scanning direction and reverses the scanning direction until the same decibel drop condition is met again, so as to record the second angle difference. The equivalent hysteresis of the motor drive chain is estimated based on the difference between the two angle differences, and the angle difference is corrected according to the equivalent hysteresis to improve the consistency of the angle difference recording.

[0045] It is understandable that the same decibel threshold is reached twice on the same axis with different force directions, and the difference in angle between the two reaches can be used as an equivalent estimate of the hysteresis. This estimate can be used to correct subsequent angle differences and as a basis for mechanical condition diagnosis.

[0046] For example, during the forward scan, when the level reaches a preset first decibel or second decibel drop condition, the first angle difference is recorded. The scan continues in the same direction beyond a preset overshoot angle, which should be sufficient to ensure a clear and stable force direction in the transmission chain. The reverse scan returns, and when the level again meets the same decibel drop condition, the second angle difference is recorded. The difference between the two angle differences serves as an estimate of the equivalent hysteresis at that threshold, yielding two hysteresis estimates for the first and second decibels respectively. If subsequent angle differences use the forward scan result, compensation can be made based on the hysteresis; alternatively, the output report can simultaneously provide both angle differences and hysteresis, using preset rules to select the more reliable one, such as selecting the retracement result as the final angle difference, to ensure consistency between the force direction and subsequent corrections. If the hysteresis exceeds the threshold, it indicates a possible abnormal mechanical condition, such as gear wear or insufficient locking, and recommends maintenance or replacement of the mounting bracket. This transforms hysteresis from an uncontrollable error into a measurable parameter, significantly improving the consistency of angle differences under commutation conditions. In multiple retests, the hysteresis estimate can also serve as an indicator of the mount's health, facilitating on-site maintenance. This is particularly critical for narrow-beam antennas, as small angular errors can significantly impact gain calculations.

[0047] In some cases, considering that pattern measurements depend on how many decibels the level drop corresponds to how much angular deviation, this relationship requires the receiver output level reading to remain linear or at least predictable with changes in input power. In reality, spectrum analyzers or receivers may use automatic gain control, front-ends may have clipping or compression, and digital intermediate frequency processing may automatically switch ranges at different levels. All of these can cause the level reading to no longer respond proportionally to input changes, meaning a 3 dB drop may not correspond to an actual 3 dB drop. In such cases, using a fixed decibel threshold to extract the angular difference will misinterpret receiver characteristics as antenna pattern characteristics. Therefore, in some examples, this also includes: Before or after performing the single-degree-of-freedom scan, a known attenuation or known gain level switch with a preset amplitude is applied to the receiving link to obtain the change in level reading. The change in level reading is then compared with the known attenuation or the known gain to perform a level linearity determination. When the level reading is determined not to meet the linearity condition, the trigger criteria for the preset first decibel and the preset second decibel are switched from a fixed decibel drop criterion to an equivalent angle width criterion based on the slope of the main lobe drop segment level change reaching a preset proportion or a preset threshold, so as to record the angle difference and use it for beamwidth and gain testing.

[0048] Understandably, a known attenuation or gain change can be applied to the receiving link before and after scanning, and the readings can be checked to see if they match the known changes. If they do not match, a criterion that does not depend on absolute decibel amplitude should be used, such as the slope ratio of the main lobe descent segment or a relative change pattern criterion.

[0049] For example, this is performed once at the start of each test or after a change in instrument range. A known change is applied via a controllable attenuator or a fixed gain setting on the receiver, and the level reading change is recorded. If the deviation between the reading change and the known change exceeds a threshold, nonlinearity is determined. If linearity is reliable, the angle difference is extracted according to a preset first decibel and a preset second decibel; if linearity is unreliable, level sequences at multiple angle points are collected in the main lobe descent segment, the local slope is calculated, and the position where the slope reaches a certain proportion or a certain threshold of the relative peak descent segment is used as the equivalent angle width trigger point. Here, the slope criterion emphasizes the curve shape rather than the absolute decibel amplitude. The output results are labeled with the criterion type used, the linearity self-test result, and the instrument range information to ensure traceability. This prevents the flattening of the level caused by receiver link compression from being mistakenly interpreted as a widening of the antenna pattern. This makes the test method more robust to different instruments and gain settings, reducing result drift caused by differences in field instrument settings. The self-test also provides a prompting capability for improper instrument settings, improving operability.

[0050] In some cases, antenna pointing deviation can lead to a drop in signal level. However, this drop can also be caused by polarization mismatch, such as incorrect feed polarization angle installation; the target satellite using a specific linear or circular polarization, but the receiver polarization not matching; and the equivalent polarization angle changing with the mount attitude under certain structural and attitude variations. If the signal level of a single polarization channel is still used as the trigger for angle difference, the angle difference may miscalculate polarization loss as a decrease in the radiation pattern, leading to an overestimation of beamwidth. Therefore, some examples also include: The antenna system includes two switchable orthogonal polarization receiving channels or dual polarization receiving channels. In the precise star pointing state and at least part of the scanning angle position of the single degree of freedom scan, the receiving levels corresponding to the two orthogonal polarizations are simultaneously acquired and the polarization ratio or polarization normalization level is calculated. When determining the angle difference corresponding to the preset first decibel and the preset second decibel, the angle difference is triggered based on the polarization normalization level rather than the level of a single polarization channel, so as to reduce the impact of polarization mismatch on beamwidth and gain testing.

[0051] Understandably, it is possible to observe the responses of two orthogonal polarizations simultaneously at the same angular position, and to use total power or polarization normalization indices to weaken the influence of polarization angle changes, making the triggering closer to a pure pointing response.

[0052] For example, the system is configured with a dual-polarization receiver head, or with two switchable orthogonal polarization receiver channels. During precise satellite pointing and scanning, the levels of the two channels are acquired at the same angular position, and the sampling timestamps are recorded to ensure synchronization. The polarization ratio is calculated, or the combined level of the two channels is calculated as the polarization normalized level. The combined level can be obtained through power domain synthesis to reduce fluctuations caused by single-channel polarization rotation. The determination of the preset first decibel and preset second decibel is no longer based on the level of a single channel, but on the decrease in the relative peak value of the polarization normalized level. If the polarization ratio changes abnormally large, it indicates that the feed polarization installation may be deviated or the satellite polarization configuration may be mismatched, facilitating on-site error correction. Thus, polarization factors and pointing factors are effectively distinguished, avoiding polarization mismatch from pulling the beamwidth and gain estimation off track. In field environments with multiple satellites and mixed standards, the method's versatility is improved. The output polarization ratio change can also help diagnose feed installation problems.

[0053] In some cases, while the antenna main lobe is ideally approximately symmetrical, in practical engineering, factors such as slight deformation of the reflector, feed eccentricity, and support obstruction can cause different descent rates on the left and right sides of the main lobe. In this situation, although the peak point is still the maximum level point, it may not correspond to the center position where the energy distribution on both sides is balanced when centered at that point. If the peak point is used as the zero point of angular difference, then in the asymmetrical main lobe, one side's threshold point is closer to the peak, and the other side is farther away. Using single-sided or double-sided threshold points to calculate the angular width will introduce a bias, and the gain obtained by the beam lobe inversion method will be affected by this center offset. Based on this, some examples also include: After determining the precise star pointing state, multiple angular level samples are collected at the angles corresponding to the peak level in both the forward and reverse directions. Based on these samples, the integral approximation of the level with respect to the angle is calculated to solve for the isoenergy center angle that makes the integral approximation on both sides of the peak level equal. When recording the angle difference corresponding to the preset first decibel and the preset second decibel, the isoenergy center angle is used as the zero point of the angle difference instead of the peak level angle, in order to improve the accuracy of beamwidth and gain testing under main lobe asymmetry conditions.

[0054] Understandably, multiple points can be sampled near the main lobe to calculate the integral approximation of the level curve, so that the center point is defined as the angular position where the integrals on both sides of the center are approximately equal. This center can better reflect the effective symmetry center of the antenna main lobe.

[0055] For example, after precise satellite pointing, starting from the peak angle, several angular positions are collected in both the forward and reverse directions to obtain the steady-state electrical level estimate. The angular range covers the near-falling segment of the main lobe but does not necessarily cover the sidelobes. The level estimate is converted to the power domain or kept consistent with a metric, and numerical integration is performed on the level versus angle curve in both the forward and reverse directions. An angular offset is found such that the approximate integral values ​​on both sides of the offset are equal. This can be achieved through interpolation or a one-dimensional search. When recording the preset first and second dB threshold points, the angle difference is calculated using the iso-energy center angle as the zero point, not the peak angle. Both the peak angle and the iso-energy center angle are retained in the output to facilitate the assessment of asymmetry. If the deviation exceeds the threshold, it indicates a possible abnormality in antenna assembly. Thus, under main lobe asymmetry conditions, the zero point of the angle difference better matches the main lobe energy distribution characteristics, making the beamwidth and gain inversion closer to the true effective aperture efficiency. It can identify and quantify the degree of main lobe asymmetry, providing a diagnostic basis for assembly eccentricity and structural deformation.

[0056] Please see Figure 2 One embodiment of the XY mount antenna gain testing device in this application is applied to a portable XY mount reflector antenna system. The XY mount includes an X-axis motor and a Y-axis motor mounted on the X-axis motor. The device includes: Selection unit 21 is used to select any geostationary orbit satellite within the antenna's field of view as a beacon source after antenna initialization is completed, so that the antenna's line of sight points to the geostationary orbit satellite. The scanning unit 22 is used to read and record the rotation angle of the X-axis motor and the rotation angle of the Y-axis motor when the peak of the signal level received by the spectrum analyzer reaches the maximum value, and use the rotation angle of the Y-axis motor as the projection angle. Under the condition of keeping the projection angle unchanged, single-degree-of-freedom scanning is performed to obtain the angle difference between the X-axis motor and the Y-axis motor relative to the precise star pointing position. The correction unit 23 is used to construct a spatial geometric projection relationship based on the projection angle, perform spatial projection correction on the obtained angle difference of the X-axis motor, and combine it with the angle difference of the Y-axis motor to calculate the actual antenna beamwidth for gain testing.

[0057] like Figure 3 As shown, this application embodiment also provides an electronic device 300, including a memory 310, a processor 320, and a computer program 311 stored in the memory 310 and executable on the processor. When the processor 320 executes the computer program 311, it implements the steps of any of the above-described methods for XY mount antenna gain testing.

[0058] Since the electronic device described in this embodiment is the device used to implement the XY mount antenna gain testing device in the embodiments of this application, those skilled in the art can understand the specific implementation method and various variations of the electronic device in this embodiment based on the method described in the embodiments of this application. Therefore, how the electronic device implements the method in the embodiments of this application will not be described in detail here. Any device used by those skilled in the art to implement the method in the embodiments of this application is within the scope of protection of this application.

[0059] In practical implementation, when the computer program 311 is executed by the processor, it can achieve the following: Figure 1 Any of the corresponding implementation methods in the embodiments.

[0060] It should be noted that the descriptions of each embodiment in the above embodiments have different focuses. For parts that are not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

Claims

1. A method for testing the gain of an XY mount antenna, applied to a portable XY mount reflector antenna system, the XY mount comprising an X-axis motor and a Y-axis motor mounted on the X-axis motor, characterized in that, The method comprises: selecting any geosynchronous orbit satellite within the field of view of the antenna as a beacon source after completing antenna initialization, and pointing the antenna boresight at the geosynchronous orbit satellite; when the spectrum analyzer receives a signal level peak value, reading and recording the X-axis motor rotation angle and the Y-axis motor rotation angle at this time, taking the Y-axis motor rotation angle as the projection deflection angle, and performing single-degree-of-freedom scanning under the condition that the projection deflection angle is unchanged to obtain the angle difference between the relative accurate star pointing positions of the X-axis motor and the Y-axis motor; constructing a spatial geometric projection relationship based on the projection deflection angle, performing spatial projection correction on the obtained angle difference of the X-axis motor, combining the angle difference of the Y-axis motor, and calculating the real antenna beam width for gain testing.

2. The method of claim 1, wherein, The antenna initialization comprises: obtaining the station longitude and latitude through the GNSS module of the antenna system; adjusting the X-axis motor and the Y-axis motor to make the antenna main lobe point to the zenith, and initializing the rotation angles of the X-axis motor and the Y-axis motor to 0°, respectively, and the rotation axis of the X-axis motor is in a horizontal state relative to the ground.

3. The method of claim 1, wherein, The method comprises: selecting any geosynchronous orbit satellite within the field of view of the antenna as a beacon source after completing antenna initialization, and pointing the antenna boresight at the geosynchronous orbit satellite; 4. The method of claim 1, wherein, selecting any geosynchronous orbit satellite within the field of view of the antenna as a beacon source after completing antenna initialization, and pointing the antenna boresight at the geosynchronous orbit satellite; The method comprises: locking the Y-axis motor and driving only the X-axis motor to scan in its rotation plane to make the antenna main lobe deviate from the direction of the geosynchronous orbit satellite while keeping the projection deflection angle unchanged; locking the X-axis motor and driving only the Y-axis motor to scan in its rotation plane to make the antenna main lobe deviate from the direction of the geosynchronous orbit satellite; locking the X-axis motor and driving only the Y-axis motor to scan in its rotation plane to make the antenna main lobe deviate from the direction of the geosynchronous orbit satellite; 5. The method of claim 1, wherein, locking the X-axis motor and driving only the Y-axis motor to scan in its rotation plane to make the antenna main lobe deviate from the direction of the geosynchronous orbit satellite. The method comprises: constructing a spatial geometric projection relationship based on the projection deflection angle, performing spatial projection correction on the obtained angle difference of the X-axis motor, obtaining the corrected equivalent beam angle difference, and making it equivalent to the angle difference obtained by scanning in the tangent plane of the orthogonal boresight great circle; Based on the obtained angle difference of the Y-axis motor and the corrected angle difference of the X-axis motor, the main lobe beam width of the antenna at a preset first decibel and a preset second decibel is calculated; The antenna gain is calculated according to the beam width by using the lobe method.

6. The method of claim 1, wherein, Further comprising: In the case that the reflector antenna has rotational symmetry, so that the main lobe beam width of the antenna in two mutually orthogonal main plane directions is equal, after the projection deflection angle is obtained and the single degree of freedom scanning of the X-axis motor is completed, the single degree of freedom scanning of the Y-axis motor is omitted; The X-axis motor angle difference corrected by the spatial projection is taken as the equivalent angle difference of the Y-axis direction to calculate the real antenna beam width and perform the gain test.

7. The method of claim 1, wherein, Further comprising: In the case that the structure of the XY pedestal is that the Y-axis motor is located at the bottom layer and the X-axis motor is installed above the Y-axis motor, when the antenna boresight accurately points to the geostationary satellite and the peak is found to reach the maximum value, the X-axis motor rotation angle and the Y-axis motor rotation angle are read and recorded, and the X-axis motor rotation angle is taken as the projection deflection angle; Under the condition that the projection deflection angle is kept unchanged, the single degree of freedom scanning is performed to obtain the angle difference of the Y-axis motor relative to the accurate pointing satellite position, and the spatial geometric projection relationship is constructed based on the projection deflection angle, the spatial projection correction of the angle difference of the Y-axis motor is performed to calculate the real antenna beam width in combination with the angle difference of the X-axis motor and perform the gain test.

8. A XY pedestal antenna gain testing device applied to a portable XY pedestal reflector antenna system, the XY pedestal comprising an X-axis motor and a Y-axis motor mounted on the X-axis motor, characterized in that, The device comprises: A selection unit is configured to select any geostationary satellite in the antenna field of view as a beacon source after the antenna is initialized, so that the antenna boresight points to the geostationary satellite; A scanning unit is configured to read and record the X-axis motor rotation angle and the Y-axis motor rotation angle when the signal level received by the spectrum analyzer reaches the maximum value, take the Y-axis motor rotation angle as the projection deflection angle, and perform the single degree of freedom scanning of the X-axis motor and the Y-axis motor respectively to obtain the angle difference of the X-axis motor and the Y-axis motor relative to the accurate pointing satellite position under the condition that the projection deflection angle is kept unchanged; A correction unit is configured to construct the spatial geometric projection relationship based on the projection deflection angle, perform the spatial projection correction of the obtained angle difference of the X-axis motor, combine the angle difference of the Y-axis motor to calculate the real antenna beam width, and perform the gain test.

9. An electronic device comprising: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor is configured to implement the steps of the XY pedestal antenna gain test method according to any one of claims 1-7 when executing the computer program stored in the memory.

10. A computer readable storage medium having stored thereon a computer program, characterized in that: The computer program is executed by the processor to implement the XY pedestal antenna gain test method according to any one of claims 1-7.

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