A method and system for fast calibration of phase using solar noise

Abstract

The application discloses a method and system for quickly calibrating phase by using solar noise, relates to the technical field of tracking and phase calibration, and comprises the following steps: acquiring a real-time position of the sun, rotating an antenna to align with the sun, finding an electric axis zero point of the antenna, and maximizing a received level value; tracking a receiver or tracking a baseband input phase value and an error factor, and setting antenna steps; adjusting an azimuth or elevation angle positive bias by controlling the antenna, adjusting the phase according to a motion track of a center point; adjusting the error factor value to make the azimuth or elevation bias reach an error voltage value according to a frequency agreement. The phase calibration result is checked, and if the phase calibration result does not meet the requirement, the phase value and the error factor are recalibrated. The application takes the sun as a wide-band radiation source, calibrates the phase by using solar noise through a tracking receiver, solves the problem that a Ka frequency band cannot establish a calibration tower for phase calibration, simultaneously does not need to change a ground system, and reduces the cost.

Description

Technical Field

[0001] This invention relates to the field of phase calibration technology, and in particular to a method and system for rapidly calibrating phase using solar noise. Background Technology

[0002] The purpose of tracking alignment is to reduce cross-coupling and ensure the tracking performance of the system, which is a key factor in preventing the loss of aircraft targets. Currently, commonly used alignment methods include: tower alignment, UAV alignment, and satellite alignment.

[0003] Traditional phase calibration involves transmitting signals from a calibration tower, drone, or satellite, with the phase value calculated by a tracking baseband or tracking receiver. Tower calibration requires vehicles and personnel to climb the tower, carrying a signal source, or transmitting signals from the tower via a remote control system. Similarly, drone calibration requires personnel to carry the drone and find a suitable location with far-field conditions. However, the ground system's ability to locate the drone and the drone's vibrations pose challenges to the calibration process.

[0004] With the development of deep space and the need for high-speed data transmission, antenna apertures and frequencies are constantly increasing. The distance and height of calibration towers meeting far-field conditions are increasing, especially for Ka-band and above, where it is impossible to establish calibration towers that meet far-field conditions. Furthermore, the cost of establishing calibration towers and related equipment is exorbitant. UAV phase calibration is also hampered by factors such as no-fly zones and battery life limitations. Available satellite resources are limited, especially on islands and ships. As the inherent limitations of traditional phase calibration methods become increasingly apparent, there is an urgent need for a method that can perform phase calibration using radio sources. Summary of the Invention

[0005] To address the aforementioned issues, this invention provides a method and system for rapid phase calibration using solar noise. By using the sun as a broadband radiation source, which can meet the far-field conditions of any frequency band, the solar-aligned signal typically provides a level more than 10 dB higher than that of the cold air. This can be used for phase calibration of energy detection tracking receivers, achieving broadband tracking phase calibration without altering any ground system. This solves the problems of traditional phase calibration methods being complex, costly, and unable to construct calibration towers for the Ka and higher frequency bands.

[0006] This invention provides a method for rapid phase calibration using solar noise, the specific technical solution of which is as follows:

[0007] S1: Obtain the real-time position of the sun, rotate the antenna to align with the sun, find the zero point of the antenna's electrical axis, and maximize the received voltage level.

[0008] S2: Track the receiver input phase value and error factor, the phase value includes azimuth phase value and elevation phase value, the error factor includes azimuth error factor and elevation error factor, and set the antenna step;

[0009] S3: Calibrate phase value and error factor;

[0010] The phase value is calibrated by controlling the antenna, adjusting the azimuth or elevation angle, and adjusting the phase according to the motion trajectory of the center point until it is the same as the theoretical motion trajectory.

[0011] The calibration of the error factor is achieved by adjusting the error factor value to obtain the error factor value that makes the azimuth or pitch offset reach the error voltage value agreed upon according to the frequency.

[0012] Furthermore, in step S3, the calibration of the phase value is specifically as follows:

[0013] By adjusting the azimuth angle for positive bias until the center point of the tracking error oscilloscope output on the system's ACU interface has a moving trajectory, when the azimuth is positively biased and a negative voltage is output, if the center point moves upward, adjust the phase value to decrease by 90°; if the center point moves downward, adjust the phase value to increase by 90°; if the center point moves to the right, adjust the phase value to increase or decrease by 180°.

[0014] Each quadrant corresponds to 90°. The phase value is increased or decreased according to the location of the center point until it is the same as the theoretical trajectory. If the center point is in the middle of the first quadrant, the phase value is decreased by 135°. If the center point is in the middle of the second quadrant, the phase value is decreased by 45°. If the center point is in the middle of the third quadrant, the phase value is increased by 45°. If the center point is in the middle of the fourth quadrant, the phase value is increased by 135°.

[0015] The corrected pitch phase value should be the same as or 180° different from the corrected azimuth phase value, and the pitch polarity should be correct.

[0016] Furthermore, after correcting the phase value and error factor, it also includes:

[0017] S4: Check the phase calibration results, which include polarity check, cross-coupling check, and tracking effect check. If the phase calibration results do not meet the requirements, the phase value and error factor are recalibrated.

[0018] Furthermore, the polarity check is performed by adjusting the azimuth and elevation angles of the antenna to check whether the polarity satisfies the condition of outputting a negative voltage when positively biased and a positive voltage when negatively biased.

[0019] Conversely, the azimuth and elevation phases are reversed by 180°.

[0020] Furthermore, the cross-coupling check involves obtaining the azimuth error voltage and pitch error voltage by adjusting the azimuth, and determining whether the ratio of the azimuth error voltage to the pitch error voltage is greater than 5:1. If not, the phase values ​​of the azimuth and pitch are recalibrated.

[0021] Furthermore, the tracking effect check is performed by directly tracking the sun to observe the tracking effect, and judging the tracking effect based on the position of the center point and the error voltage.

[0022] Self-tracking means that the ground-based tracking system automatically follows the sun's trajectory to maximize the received signal level. If the small dot on the tracking error oscilloscope of the system's ACU (Antenna Control Unit) interface is always in the center of the crosshair and the error voltage is less than 0.01V, it indicates stable tracking. If the small dot circles, it means that the azimuth and elevation phase values ​​are not properly calibrated and need to be recalibrated. If the small dot oscillates back and forth but does not lose track of the target, it means that the error factor is too large. If the small dot deviates from the center point but returns to its original position very slowly, it means that the error factor is too small. If the error factor is too large or too small, it needs to be recalibrated.

[0023] Furthermore, the real-time position of the sun is obtained through the Orbitron software.

[0024] Furthermore, the setting of the antenna step is specifically as follows:

[0025] The step size for C-band and below can be set to 0.03°, and the step size for X-band and above can be set to 0.01°.

[0026] The present invention also discloses a system for rapidly calibrating phase using solar noise, wherein the system applies the method for rapidly calibrating phase using solar noise described above;

[0027] The system includes an antenna, a noise amplifier, a downconverter, a tracking receiver or tracking baseband, an antenna control unit, and an antenna drive unit.

[0028] The antenna feed is connected to the tracking receiver or tracking baseband via the noise amplifier and downconverter, and the tracking receiver or tracking baseband is connected to the antenna via the antenna control unit and antenna drive unit.

[0029] The beneficial effects of this invention are as follows:

[0030] This invention uses the sun as a broadband radiation source, which can meet the far-field conditions of any frequency band. By utilizing solar noise, phase calibration is performed through a tracking receiver. Phase calibration in incoherent mode can be completed without calibration towers, drones and related equipment. This solves the problem that it is impossible to establish calibration towers for phase calibration in the Ka band. At the same time, it does not require changes to the ground system, saving manpower and material costs for phase calibration work. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the method flow of the present invention.

[0032] Figure 2 This is a schematic diagram of the system structure of the present invention. Detailed Implementation

[0033] The technical solutions in the embodiments of the present invention are clearly and completely described in the following description. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0034] In the description of the embodiments of the present invention, it should be noted that the indicated orientation or positional relationship is based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of the invention is conventionally placed during use, or the orientation or positional relationship in which those skilled in the art conventionally understand it during use. This is only for the convenience of describing the present invention and simplifying the description, and is not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of the present invention. Furthermore, the terms "first" and "second" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0035] In the description of the embodiments of the present invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set" and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the present invention based on the specific circumstances.

[0036] Example 1

[0037] Embodiment 1 of the present invention discloses a method for rapid phase calibration using solar noise, such as... Figure 1 As shown, the details are as follows:

[0038] S1: Obtain the real-time position of the sun, rotate the antenna to align with the sun, find the zero point of the antenna's electrical axis, and maximize the received voltage level.

[0039] The real-time position of the sun can be obtained through third-party software, and no specific limitation is made here. In this embodiment, the real-time position of the sun can be obtained through Orbitron software.

[0040] S2: Track the initial values ​​of the input phase value and error factor of the tracking receiver, wherein the phase value includes the azimuth phase value and the elevation phase value, and the error factor includes the azimuth error factor and the elevation error factor, and set the antenna step;

[0041] In this embodiment, the setting of the antenna step is specifically as follows:

[0042] The step size for C-band and below can be set to 0.03°, and the step size for X-band and above can be set to 0.01°.

[0043] S3: Calibrate phase value and error factor;

[0044] The phase value is calibrated by controlling the antenna, adjusting the azimuth or elevation angle, and adjusting the phase according to the motion trajectory of the center point until it is the same as the theoretical motion trajectory.

[0045] In this embodiment, the calibration of the phase value includes the calibration of the azimuth phase value and the calibration of the pitch phase value;

[0046] Specifically as follows:

[0047] Adjust the azimuth or pitch angle to positive bias until the center point of the tracking error oscilloscope has a movement trajectory. When the azimuth is positive biased and a negative voltage is generated, if the center point moves upward, adjust the phase value to decrease by 90°; if the center point moves downward, adjust the phase value to increase by 90°; if the center point moves to the right, adjust the phase value to increase or decrease by 180°.

[0048] The tracking error oscilloscope is an oscilloscope simulation waveform output by the ACU on the interface based on the phase value and error voltage;

[0049] Each quadrant corresponds to 90°. The phase value is increased or decreased according to the location of the center point until it matches the theoretical trajectory. If the center point is in the middle of the first quadrant, the phase value is decreased by 135°. If the center point is in the middle of the second quadrant, the phase value is decreased by 45°. If the center point is in the middle of the third quadrant, the phase value is increased by 45°. If the center point is in the middle of the fourth quadrant, the phase value is increased by 135°.

[0050] The sun is a patch source, not a point source, relative to the ground-based tracking system. Due to the sun's wide angular radius, the antenna needs to be deflected many times in appropriate steps before a change is observed. Careful observation of the pattern is required. Therefore, the higher the frequency, the greater the difficulty in phase calibration. For example, with a 0.01° step, if it's a patch source, it might require dozens of deflections to deviate from the sun; if it's a point source, a single deflection is sufficient. This embodiment solves the phase calibration difficulty caused by the sun's wide angular radius by adjusting the deflection angle and performing multiple phase corrections based on the center point's trajectory.

[0051] The calibration process for the pitch phase value is the same as that for the azimuth phase value. Alternatively, the same phase value as the azimuth can be directly entered. Pitch the pitch to check the pitch polarity and observe whether the center point moves on the Y-axis. If a negative voltage is generated when the pitch is positive, the value is correct. If a positive voltage is generated when the pitch is positive, the difference is 180°.

[0052] The error factor is calibrated by increasing or decreasing the error factor value to obtain the error factor value that makes the azimuth or pitch offset reach the error voltage value agreed upon according to the frequency.

[0053] The first step is to obtain the phase value to ensure correct polarity. By convention, a positive bias results in a negative voltage, and a negative bias in a positive voltage. When the antenna deviates from the target, a voltage is applied to pull the antenna back. If the polarity is reversed, the antenna's direction of movement will be reversed, causing the target to be lost. The second step is to obtain the error factor, or gain, which determines the amount of force required to pull the antenna. Too much force might cause over-pulling, resulting in antenna oscillation; too little force will result in insufficient force to keep up with the target.

[0054] S4: Check the phase calibration results, which include polarity check, cross-coupling check, and tracking effect check. If the phase calibration results do not meet the requirements, the phase value and error factor are recalibrated.

[0055] In this embodiment, the polarity check is performed by adjusting the azimuth and elevation angles of the antenna to check whether the polarity satisfies the condition of outputting a negative voltage when positively biased and a positive voltage when negatively biased; if the opposite is true, the azimuth and elevation phases are reversed by 180°.

[0056] The cross-coupling check involves adjusting the azimuth to obtain the azimuth error voltage and the elevation error voltage. It then determines whether the ratio of the azimuth error voltage to the elevation error voltage is greater than 5:1. If not, it indicates that the phase value calibration is poor, which will lead to tracking instability. The phenomenon is that the antenna will "draw circles" during the tracking process, which may become larger and larger, resulting in target loss. The azimuth and elevation phase values ​​need to be recalibrated.

[0057] Theoretically, when adjusting the azimuth, only the azimuth error voltage should be present, while the pitch error voltage should be zero. The ratio of the azimuth error voltage to the pitch error voltage should be greater than 5:1. When adjusting the pitch, the azimuth error voltage should also be zero. However, in practice, the error voltage will not be zero. As long as the ratio does not exceed 5:1, tracking is possible. If it exceeds 5:1, it indicates that the phase value calibration is not good and recalibration is required.

[0058] The tracking effect check is performed by directly tracking the sun to observe the tracking effect, and judging the tracking effect based on the position of the center point and the error voltage.

[0059] Self-tracking means that the ground-based tracking system automatically follows the sun's trajectory to maximize the received signal level. If the small dot on the tracking error oscilloscope of the system's ACU (Antenna Control Unit) interface is always in the center of the crosshair and the error voltage is less than 0.01V, it indicates stable tracking. If the small dot circles, it means that the azimuth and elevation phase values ​​are not properly calibrated and need to be recalibrated. If the small dot oscillates back and forth but does not lose track of the target, it means that the error factor is too large. If the small dot deviates from the center point but returns to its original position very slowly, it means that the error factor is too small. If the error factor is too large or too small, it needs to be recalibrated.

[0060] Example 2

[0061] Embodiment 2 of the present invention discloses a system for rapid phase calibration using solar noise, wherein the system applies the method for rapid phase calibration using solar noise described in Embodiment 1 above;

[0062] like Figure 2 As shown, the system includes an antenna, a noise amplifier, a downconverter, a tracking receiver or tracking baseband, an antenna control unit, and an antenna drive unit;

[0063] The tracking receiver can be configured with both wideband and narrowband tracking modes, both of which support the method described in Example 1.

[0064] The tracking baseband modes are divided into standard tracking, spread spectrum tracking, and data transmission tracking. Standard tracking and spread spectrum tracking are narrowband tracking, while data transmission tracking is wideband tracking. When tracking the baseband, the tracking mode is selected according to the actual situation, in conjunction with the method described in Example 1.

[0065] Specifically, the tracking mode should be set to wideband. If the actual tracking mode is narrowband, it should also be set to wideband during phase calibration.

[0066] The antenna feed is connected to the tracking receiver via the noise amplifier and downconverter, and the tracking receiver is connected to the antenna via the antenna control unit and the antenna drive unit.

[0067] This invention is not limited to the specific embodiments described above. The invention extends to any new feature or combination disclosed in this specification, as well as any new method or process step or combination disclosed herein.

Claims

1. A method for rapid phase calibration using solar noise, characterized in that, include: S1: Obtain the real-time position of the sun, rotate the antenna to align with the sun, find the zero point of the antenna's electrical axis, and maximize the received voltage level. S2: Track the receiver or track the baseband input phase value and error factor, the phase value including azimuth phase value and elevation phase value, the error factor including azimuth error factor and elevation error factor, and set the antenna step; S3: Calibrate phase value and error factor; The phase value is calibrated by controlling the antenna, adjusting the azimuth or elevation angle, and adjusting the phase according to the motion trajectory of the center point until it matches the theoretical motion trajectory; specifically as follows: By adjusting the azimuth angle for positive bias until the center point of the tracking error oscilloscope has a movement trajectory, when the azimuth is positively biased and a negative voltage is generated, if the center point moves upward, adjust the phase value to decrease by 90°; if the center point moves downward, adjust the phase value to increase by 90°; if the center point moves to the right, adjust the phase value to increase or decrease by 180°. Each quadrant corresponds to 90°. The phase value is increased or decreased according to the location of the center point until it is the same as the theoretical trajectory. If the center point is in the middle of the first quadrant, the phase value is decreased by 135°. If the center point is in the middle of the second quadrant, the phase value is decreased by 45°. If the center point is in the middle of the third quadrant, the phase value is increased by 45°. If the center point is in the middle of the fourth quadrant, the phase value is increased by 135°. The corrected pitch phase value is the same as the corrected azimuth phase value, or differs from it by 180°. As long as the pitch polarity is correct, the pitch polarity can be checked by tilting the pitch. Observe whether the center point moves on the Y-axis. If a negative voltage is generated when tilting positively, the value is correct. If a positive voltage is generated when tilting positively, the difference of 180° is acceptable. The calibration of the error factor is achieved by adjusting the error factor value to obtain the error factor value that makes the azimuth or pitch offset reach the error voltage value agreed upon according to the frequency.

2. The method for rapid phase calibration using solar noise according to claim 1, characterized in that, After correcting the phase value and error factor, it also includes: S4: Check the phase calibration results, which include polarity check, cross-coupling check, and tracking effect check. If the phase calibration results do not meet the requirements, the phase value and error factor are recalibrated.

3. The method for rapid phase calibration using solar noise according to claim 2, characterized in that, The polarity check is performed by adjusting the azimuth and elevation angles of the tilted antenna to check whether the polarity satisfies the condition of outputting a negative voltage when positively tilted and a positive voltage when negatively tilted.

4. The method for rapid phase calibration using solar noise according to claim 2, characterized in that, The cross-coupling check involves obtaining the azimuth error voltage and pitch error voltage by adjusting the azimuth, and determining whether the ratio of the azimuth error voltage to the pitch error voltage is greater than 5:

1. If not, the azimuth phase value is recalibrated.

5. The method for rapid phase calibration using solar noise according to claim 2, characterized in that, The tracking effect check is performed by directly tracking the sun to observe the tracking effect, and judging the tracking effect based on the position of the center point and the error voltage.

6. The method for rapid phase calibration using solar noise according to claim 1, characterized in that, The real-time position of the sun can be obtained using Orbitron software.

7. The method for rapid phase calibration using solar noise according to claim 1, characterized in that, The antenna step setting is specifically as follows: The step size for C-band and below can be set to 0.03°, and the step size for X-band and above can be set to 0.01°.

8. A system for rapidly calibrating phase using solar noise, characterized in that, The system employs the method for rapid phase calibration using solar noise as described in any one of claims 1-7; The system includes an antenna, a noise amplifier, a downconverter, a tracking receiver or tracking baseband, an antenna control unit, and an antenna drive unit. The antenna feed is connected to the tracking receiver or tracking baseband via the noise amplifier and downconverter, and the tracking receiver or tracking baseband is connected to the antenna via the antenna control unit and antenna drive unit.

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