Automatic calibration method for polarization angle of Ku-band satellite communication antenna

Abstract

The invention discloses an automatic calibration method for a polarization angle of a Ku-band satellite communication antenna, and belongs to the technical field of antenna calibration. The method comprises the following steps: acquiring attitude information of a carrier in real time; setting satellite parameters according to the target satellite information, and sending a polarization calibration instruction; calculating a satellite pointing deck angle of the antenna in real time to obtain a polarized satellite pointing deck angle; quickly rotating the polarization position from the current position to a clockwise limit position, recording a clockwise limit angle, then quickly rotating to an anticlockwise limit position again, and recording an anticlockwise limit angle; the antenna polarization axis automatically rotates clockwise at a fixed angular velocity and detects a current satellite beacon signal power value, when the beacon signal power value jumps, a corresponding angle is recorded, rotation continues until the signal jumps for the second time, and the corresponding angle is recorded; and calculating a polarization calibration angle to complete polarization angle calibration. The method is simple and easy to implement, is high in reliability, reduces the labor cost, and can achieve the precise calibration of the polarization angle.

Description

Technical Field

[0001] The invention relates to the technical field of antenna calibration, and in particular to an automatic calibration method for the polarization angle of a Ku-band satellite communication antenna. Background Art

[0002] Ku-band satellite communication antennas need to adjust their polarization angles in real time according to the polarization mode of the target satellite to meet the requirements of antenna tracking and satellite communication. However, when the polarization angle calibration of the communication antenna has a large error, the signal transmitted by the antenna will interfere with the satellite, which may affect its own communication quality at the least, or pose a serious threat to the communication of other communication terminal devices on the current satellite, affecting the entire satellite operation.

[0003] The following problems may occur when polarization is not calibrated or is calibrated manually:

[0004] 1) Most polarization devices do not have a 0-degree scale line. Even if they do, it is found in actual use that the 0-degree angle given by them often has errors. If the error is not corrected, it will pose a hidden danger to satellite communications;

[0005] 2) If manual polarization calibration is used, each antenna needs to be manually calibrated. When the number of antennas is small, human resources can be sufficient and the calibration quality can be guaranteed. However, when the number of antennas is large and the factory delivery cycle is tight, it will greatly occupy human resources, bring huge labor costs, and cannot guarantee the polarization calibration quality of the antenna;

[0006] 3) The polarization angle of the satellite itself often has errors, and the polarization errors generated by the antenna when facing different satellites are also different. It is neither realistic nor possible to manually calibrate the Ku-band satellite communication antenna every time the target satellite is changed. Summary of the invention

[0007] Aiming at the problem in the prior art that inaccurate polarization angle of Ku-band satellite communication antenna will interfere with satellite communication, and the problem that manual calibration of polarization angle will occupy a large amount of human resources and the calibration quality cannot be guaranteed, the present invention proposes a method for automatic calibration of polarization angle of Ku-band satellite communication antenna.

[0008] The technical solution of the present invention is:

[0009] A method for automatically calibrating the polarization angle of a Ku-band satellite communication antenna comprises the following steps:

[0010] Step 1: The Ku-band satellite communication antenna communicates with the inertial navigation device to obtain the carrier's attitude information in real time, including latitude and longitude, heading, roll, and pitch;

[0011] Step 2: Set satellite parameters according to target satellite information and send polarization calibration instructions;

[0012] Step 3: Calculate the theoretical value of the antenna pointing to the satellite according to the target satellite information, and calculate the antenna's pointing deck angle in real time according to the theoretical value and the position and attitude changes of the carrier during movement, where the polarization pointing deck angle is P j ;

[0013] Step 4: If the polarization axis of the Ku-band satellite communication antenna has no limit, skip this step; if the Ku-band satellite communication antenna has forward and reverse limits on the polarization axis, and the polarization angle is located and confirmed by the forward and reverse limits on the polarization axis, quickly rotate the polarization position from the current position to the forward limit, record the forward limit angle P1, and then quickly rotate it to the reverse limit again, record the reverse limit angle P2, and calculate the range of polarization movement △P 12 =P1-P2, if △P 12 If it is less than 95% of the designed polarization angle range, it indicates that the calibration has failed;

[0014] Step 5: The antenna polarization axis automatically rotates clockwise at a fixed angular velocity and detects the current satellite beacon signal power value. When the beacon signal power value jumps, the corresponding angle P3 is recorded, and the rotation continues until the signal jumps for the second time, and the corresponding angle P4 is recorded.

[0015] Step 6: If the signal increases when the signal jumps for the first time and decreases when the signal jumps for the second time, the polarization calibration angle is △P = P j -(P3+P4) / 2;

[0016] Step 7: If the signal decreases when the signal changes for the first time and increases when the signal changes for the second time, the polarization calibration angle is △P = P j -(P3+P4) / 2+90, when △P is greater than 180 degrees, let △P=△P-180;

[0017] Step 8: If the polarization axis of the Ku-band satellite communication antenna is not limited, △P is added to the previous polarization calibration point to complete the polarization angle calibration;

[0018] If the Ku-band satellite communication antenna has forward and reverse limits on the polarization axis, and the polarization angle is located and confirmed by the forward and reverse limits on the polarization axis, the forward and reverse limits are calibrated respectively:

[0019] If the calibration point is the forward limit, the original forward limit angle is P s , then the limit is marked as P sx =P s +△P, the inverse limit is calibrated as P nx =P sx -△P 12 ;

[0020] If the calibration point is the inverse limit, the original inverse limit angle is Pn , then the inverse limit is marked as P nx =P n +△P, the limit is calibrated as P sx =P nx +△P 12 .

[0021] Furthermore, before step 8, the following steps are also included:

[0022] Follow steps 4 to 7 again, where the forward rotation at a fixed angular velocity in step 5 is changed to the reverse rotation at a fixed angular velocity; the △P obtained after the first execution of steps 4 to 7 is recorded as △P1, and the △P obtained after the second execution of steps 4 to 7 is recorded as △P2; if the difference between △P1 and △P2 is less than 2 degrees, the △P in step 8 is taken as the average value of △P1 and △P2 △P=(△P1+△P2) / 2; if the difference between △P1 and △P2 is greater than 2 degrees, it is prompted that the calibration has failed and step 8 is no longer executed.

[0023] The beneficial effects of the present invention are:

[0024] 1. The present invention is implemented by software, and the polarization angle is accurately calibrated by rotating the polarization axis to find the reverse polarization point.

[0025] 2. The present invention can be embedded in an antenna control unit or in an antenna upper-level control terminal. It can be operated with one button, is convenient and practical, and can calibrate multiple antennas at the same time, thus freeing up human resources and reducing labor costs.

[0026] 3. The present invention improves the reliability of the antenna. After the antenna is replaced with a satellite, automatic polarization calibration can be performed quickly to solve the problem of angle errors in polarizations of different satellites. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a processing flow chart of automatic calibration when polarization is not infinite in an embodiment of the present invention.

[0028] Figure 2 It is a processing flow chart of automatic calibration when polarization is limited in an embodiment of the present invention.

[0029] Figure 3 This is a diagram showing the effect of the signal first increasing and then decreasing during the polarization rotation process.

[0030] Figure 4 This is a diagram showing the effect of the signal first becoming smaller and then becoming larger during the polarization rotation process. DETAILED DESCRIPTION

[0031] The present invention is further described in detail below in conjunction with the accompanying drawings.

[0032] A method for automatically calibrating the polarization angle of a Ku-band satellite communication antenna, such as Figure 1 As shown, the following steps are included:

[0033] 1) The Ku-band satellite communication antenna communicates with inertial navigation equipment and other equipment to obtain the carrier's attitude information in real time, including latitude and longitude, heading, roll, pitch, etc.;

[0034] 2) According to the target satellite information, the user sets the satellite parameters and sends polarization calibration instructions;

[0035] 3) The antenna can calculate the satellite pointing angle, calculate the theoretical value of the antenna according to the target satellite information, and calculate the antenna's satellite pointing deck angle in real time according to the theoretical value and the position and attitude changes during the carrier's movement, where the polarization satellite deck angle is P j ;

[0036] 4) The antenna polarization axis automatically rotates clockwise at a fixed angular velocity and detects the current satellite beacon signal power value. When the beacon signal power value jumps, the angle P3 is recorded, and the rotation continues until the signal jumps for the second time, and the angle P4 is recorded;

[0037] 5) If Figure 3 As shown in the figure, when the signal jumps for the first time, the signal increases, and when the signal jumps for the second time, the signal decreases. Then the polarization calibration angle △P1 is △P1=P j -(P3+P4) / 2. The threshold of the signal transition in this step can be adjusted by the operator according to actual use, and the threshold of the same type of antennas can be universal.

[0038] 6) If Figure 4 As shown, when the signal jumps for the first time, the signal becomes smaller, and when the signal jumps for the second time, the signal becomes larger, then: The polarization calibration angle △P1 is △P1=P j -(P3+P4) / 2+90, when △P1 is greater than 180 degrees, △P1=△P1-180. The threshold of the signal jump in this step can be the same as that in step 6), and can also be adjusted by the operator according to actual use;

[0039] 7) Repeat steps 4, 5, and 6. In step 4, change to polarization reversal and calculate △P2. When the difference between △P1 and △P2 is less than 2 degrees, use the average value of these two numbers △P = (△P1 + △P1) / 2, and add this value to the previous polarization calibration point to complete the polarization angle calibration. If the difference between △P1 and △P2 is greater than 2 degrees, the operator is prompted that the calibration has failed. Please manually check whether there is a problem.

[0040] 8) If the Ku-band satellite communication antenna has a polarization axis forward or reverse limit, and the polarization angle is located and confirmed by the axis forward or reverse limit, when the calibration point is the forward limit, the original forward limit angle is P s, then the limit is marked as P sx =P s +△P, the inverse limit is calibrated as P nx =P sx -△P 12 When the calibration point is the inverse limit, the original inverse limit angle is P n , then the inverse limit is marked as P nx =P n +△P, the limit is calibrated as P sx =P nx +△P 12 .

[0041] A method for automatically calibrating the polarization angle of a Ku-band satellite communication antenna, such as Figure 2 As shown, the following steps are included:

[0042] 1) The Ku-band satellite communication antenna communicates with inertial navigation equipment and other equipment to obtain the carrier's attitude information in real time, including latitude and longitude, heading, roll, pitch, etc.;

[0043] 2) According to the target satellite information, the user sets the satellite parameters and sends polarization calibration instructions;

[0044] 3) The antenna can calculate the satellite pointing angle, calculate the theoretical value of the antenna according to the target satellite information, and calculate the antenna's satellite pointing deck angle in real time according to the theoretical value and the position and attitude changes during the carrier's movement, where the polarization satellite deck angle is P j ;

[0045] 4) If the Ku-band satellite communication antenna has a polarization axis forward or reverse limit, and the polarization angle is located and confirmed by the axis forward or reverse limit, the polarization is quickly rotated from the current position to the forward limit, the forward limit angle P1 is recorded, and then it is quickly rotated to the reverse limit again, the reverse limit angle P2 is recorded, and the range of polarization movement △P is calculated 12 =P1-P2, △P 12 If it is less than 95% of the designed polarization angle range, the operator is prompted that the calibration has failed. Please manually check whether there is a problem;

[0046] 5) The antenna polarization axis automatically rotates clockwise at a fixed angular velocity and detects the current satellite beacon signal power value. When the beacon signal power value jumps, the angle P3 is recorded, and the rotation continues until the signal jumps for the second time, and the angle P4 is recorded;

[0047] 6) If Figure 3 As shown in the figure, when the signal jumps for the first time, the signal increases, and when the signal jumps for the second time, the signal decreases. Then the polarization calibration angle △P1 is △P1=P j -(P3+P4) / 2. The threshold of the signal transition in this step can be adjusted by the operator according to actual use, and the threshold of the same type of antennas can be universal.

[0048] 7) If Figure 4 As shown, when the signal jumps for the first time, the signal becomes smaller, and when the signal jumps for the second time, the signal becomes larger, then: The polarization calibration angle △P1 is △P1=P j -(P3+P4) / 2+90, when △P1 is greater than 180 degrees, △P1=△P1-180. The threshold of the signal jump in this step can be the same as that in step 6), and can also be adjusted by the operator according to actual use;

[0049] 8) Repeat steps 4, 5, 6, and 7. In step 5, change to polarization reversal and calculate △P2. When the difference between △P1 and △P2 is less than 2 degrees, use the average value of these two numbers △P=(△P1+△P1) / 2, and add this value to the previous polarization calibration point to complete the polarization angle calibration. If the difference between △P1 and △P2 is greater than 2 degrees, the operator is prompted that the calibration has failed. Please manually check whether there is a problem.

[0050] 9) If the Ku-band satellite communication antenna has a polarization axis forward or reverse limit, and the polarization angle is located and confirmed by the axis forward or reverse limit, when the calibration point is the forward limit, the original forward limit angle is P s , then the limit is marked as P sx =P s +△P, the inverse limit is calibrated as P nx =P sx -△P 12 When the calibration point is the inverse limit, the original inverse limit angle is P n , then the inverse limit is marked as P nx =P n +△P, the limit is calibrated as P sx =P nx +△P 12 .

[0051] In the above method, if the user wants to calibrate quickly, step 8 can be skipped to reduce the calibration time, but this may cause errors in the polarization calibration.

[0052] The present invention is no different from the previous Ku-band satellite communication antenna in terms of structural design and hardware design. It is mainly implemented by software. By rotating the polarization axis to find the anti-polarization point, the polarization angle is accurately calibrated. It has low cost and high value. It can solve the problems in the prior art that the inaccurate polarization angle of the Ku-band satellite communication antenna interferes with satellite communication and that manual polarization calibration takes up a lot of human resources and the calibration results cannot be guaranteed.

[0053] The present invention can be embedded in an antenna control unit or in an antenna superior control terminal. It is one-touch operation, convenient and practical. It can calibrate multiple antennas at the same time, freeing up human resources, reducing labor costs, and improving the reliability of the antenna. After the satellite is replaced, the antenna can also be quickly and automatically polarized and calibrated to solve the problem of angle errors in polarizations of different satellites.

Claims

1. A method for automatically calibrating the polarization angle of a Ku-band satellite communication antenna, characterized in that: The following steps are involved: Step 1: The Ku-band satellite communication antenna communicates with the inertial navigation device to obtain the carrier's attitude information in real time, including latitude and longitude, heading, roll, and pitch; Step 2: Set satellite parameters according to target satellite information and send polarization calibration instructions; Step 3: Calculate the theoretical value of the antenna pointing to the satellite according to the target satellite information, and calculate the antenna's pointing deck angle in real time according to the theoretical value and the position and attitude changes of the carrier during movement, where the polarization pointing deck angle is P j ; Step 4: If the polarization axis of the Ku-band satellite communication antenna has no limit, skip this step; if the Ku-band satellite communication antenna has forward and reverse limits on the polarization axis, and the polarization angle is located and confirmed by the forward and reverse limits on the polarization axis, quickly rotate the polarization position from the current position to the forward limit, record the forward limit angle P1, and then quickly rotate it to the reverse limit again, record the reverse limit angle P2, and calculate the range of polarization movement △P 12 =P1-P2, if △P 12 If it is less than 95% of the designed polarization angle range, it indicates that the calibration has failed; Step 5: The antenna polarization axis automatically rotates clockwise at a fixed angular velocity and detects the current satellite beacon signal power value. When the beacon signal power value jumps, the corresponding angle P3 is recorded, and the rotation continues until the signal jumps for the second time, and the corresponding angle P4 is recorded. Step 6: If the signal increases when the signal jumps for the first time and decreases when the signal jumps for the second time, the polarization calibration angle is △P = P j -(P3+P4) / 2; Step 7: If the signal decreases when the signal jumps for the first time and increases when the signal jumps for the second time, the polarization calibration angle is △P = P j -(P3+P4) / 2+90, when △P is greater than 180 degrees, let △P=△P-180; Step 8: If the polarization axis of the Ku-band satellite communication antenna is not limited, △P is added to the previous polarization calibration point to complete the polarization angle calibration; If the Ku-band satellite communication antenna has forward and reverse limits on the polarization axis, and the polarization angle is located and confirmed by the forward and reverse limits on the polarization axis, the forward and reverse limits are calibrated respectively: If the calibration point is the forward limit, the original forward limit angle is P s , then the limit is marked as P sx =P s +△P, the inverse limit is calibrated as P nx =P sx -△P 12 ; If the calibration point is the inverse limit, the original inverse limit angle is P n , then the inverse limit is marked as P nx =P n +△P, the limit is calibrated as P sx =P nx +△P 12 .

2. The method for automatically calibrating the polarization angle of a Ku-band satellite communication antenna according to claim 1, characterized in that: Before step 8 also include: Follow steps 4 to 7 again, where the forward rotation at a fixed angular velocity in step 5 is changed to the reverse rotation at a fixed angular velocity; the △P obtained after the first execution of steps 4 to 7 is recorded as △P1, and the △P obtained after the second execution of steps 4 to 7 is recorded as △P2; if the difference between △P1 and △P2 is less than 2 degrees, the △P in step 8 is taken as the average value of △P1 and △P2 △P=(△P1+△P2) / 2; if the difference between △P1 and △P2 is greater than 2 degrees, it is prompted that the calibration has failed and step 8 is no longer executed.

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