Radar azimuth antenna sector scanning control method

Abstract

The invention discloses a radar azimuth antenna sector scanning control method, and particularly relates to the field of servo control. Comprising the following steps: dividing a sector-scanning period into six stages to obtain sector-scanning time of each stage; according to the sector-scanning range and the sector-scanning time, the sector-scanning speed of the constant-speed stage is determined; determining a sector-scan acceleration according to the sector-scan speed; according to the corresponding sector-scanning acceleration and sector-scanning speed, respectively determining the sector-scanning speed of all position points in the sector-scanning period; carrying out integration on the sector scanning speeds of all position points in the sector scanning period to obtain continuous position code information; and controlling antenna sector scanning according to the position code information. The problem of equipment jittering caused by the fact that the radar azimuth antenna directly uses PID control and speed loop control can be avoided; the system stability and precision in the sector scanning process are improved, and it is guaranteed that the speed error within the range of-90 degrees to 90 degrees is smaller than 5%.

Description

Technical Field

[0001] The present application relates to the field of servo control, and in particular to a radar azimuth antenna fan-sweep control method. Background Art

[0002] Mechanical scanning search radar scans the space by rotating the antenna in azimuth to obtain target information in a fixed airspace. The faster the scanning speed, the faster the information refresh speed, and the faster and more real-time information status of the target airspace can be grasped. However, fast scanning, especially fast periodic fan scanning, requires constant and rapid switching of the movement direction, which will reduce the stability of the device, cause device jitter, and affect device performance and safety. At the same time, it is also hoped that the uniform speed section during the fan scanning process is as long as possible, because the device is relatively more stable in the uniform speed section, and the stability of signal transmission and reception is better.

[0003] The average fan-sweep speed of a conventional search radar antenna generally does not exceed 30° / s. Tracking radars have high requirements for dynamic response, and the maximum fan-sweep speed is required to reach 90° / s. However, since tracking radars are relatively small in size and now mostly use direct drive, they have good dynamic performance. Direct use of a speed loop or a simple position loop for fan-sweep control can also meet basic control requirements. However, for the radar azimuth, a periodic fan-sweep within the range of -120°~120° is required within 4S, and the average fan-sweep speed is required to be 120° / s. Traditional control methods have poor speed stability during the fan-sweep process, and are prone to jitter when approaching the fan-sweep boundary. Summary of the invention

[0004] The main purpose of the present application is to provide a radar azimuth antenna fan-sweep control method, aiming to solve the problem that the fan-sweep is prone to jitter due to the existing control method.

[0005] To achieve the above-mentioned purpose, the present application provides a radar azimuth antenna fan-sweep control method, including: obtaining the fan-sweep range and fan-sweep period of the antenna, dividing the fan-sweep period into a forward uniform acceleration stage, a forward uniform speed stage, a forward uniform deceleration stage, a reverse uniform acceleration stage, a reverse uniform speed stage, and a reverse uniform deceleration stage, and obtaining the fan-sweep time of each stage; determining the fan-sweep speed of the forward uniform speed stage according to the fan-sweep range, the fan-sweep time of the forward uniform acceleration stage, the fan-sweep time of the forward uniform deceleration stage, and the fan-sweep time of the forward uniform speed stage; determining the fan-sweep acceleration of the forward uniform acceleration stage according to the fan-sweep speed; wherein, the fan-sweep speed of the forward uniform speed stage and the reverse uniform speed stage are The fan sweep speeds in the acceleration stage are the same in magnitude and opposite in direction; the fan sweep accelerations in the forward uniform acceleration stage, the forward uniform deceleration stage, the reverse uniform acceleration stage and the reverse uniform deceleration stage are all the same in magnitude; according to the corresponding fan sweep accelerations and fan sweep speeds, the fan sweep speed of each position point in the forward uniform acceleration stage, the fan sweep speed of each position point in the forward uniform deceleration stage, the fan sweep speed of each position point in the reverse uniform acceleration stage, and the fan sweep speed of each position point in the reverse uniform deceleration stage are respectively determined; the fan sweep speeds of all position points in the fan sweep period are integrated to obtain continuous position code information; and the antenna fan sweep is controlled according to the position code information.

[0006] Optionally, the formula for the fan sweep speed in the forward uniform speed stage is:

[0007] In the formula, is the fan sweep range, is the fan sweep time in the forward uniform acceleration stage, is the fan sweep time in the forward uniform speed stage, is the fan sweep time in the positive uniform deceleration stage.

[0008] Optionally, the fan sweep time in the forward uniform speed stage and the reverse uniform speed stage accounts for 70-80% of the fan sweep cycle.

[0009] Optionally, the method further includes controlling the antenna to perform uniform deceleration motion until the speed reaches zero when a stop instruction is received.

[0010] Optionally, after the speed of the antenna is zero, the method further includes: determining a zeroing error according to the zero position and current position of the antenna, and performing closed-loop position control on the antenna according to the zeroing error to return the antenna to the zero position.

[0011] Optionally, the position closed-loop control includes: when the zeroing error is greater than a stability threshold, controlling the antenna to move at a uniform speed; and when the zeroing error is less than or equal to the stability threshold, controlling the antenna to move at a uniform deceleration speed.

[0012] Optionally, before controlling the antenna fan scan according to the position code information, the method further includes: acquiring the current position of the antenna, and when it is determined that the current position of the antenna is outside the fan scan range, controlling the antenna to return to the fan scan range.

[0013] Compared with the prior art, the present invention has the following beneficial effects: A radar azimuth antenna fan-sweep control method divides the fan-sweep cycle into multiple stages, determines the speed of each stage, determines the position information according to the speed, that is, determines the control path, and controls according to the position information through PID control, thereby avoiding the problem of large fan-sweep angle, short cycle, difficult traditional PID tuning, large overshoot, large speed change during commutation, and equipment jitter caused by direct use of PID control and speed loop control of the radar azimuth antenna; makes the fan-sweep process in uniform motion for most of the time, improves the system stability and accuracy during the fan-sweep process; and can adjust the speed and acceleration to achieve the adjustment of the dynamic performance of the radar azimuth antenna for different scanning stability domains (uniform speed segments). It can ensure that the speed error within the range of -90°~90° is less than 5%. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 A schematic flow chart of a radar azimuth antenna fan-sweep control method for the present application; Figure 2 This is a theoretical speed curve diagram of Example 1 of the present application; Figure 3 This is a theoretical path curve diagram of Example 1 of the present application; Figure 4 This is an actual speed curve diagram of Example 1 of the present application; Figure 5 This is an actual path curve diagram of Example 1 of the present application; Figure 6 This is a diagram showing the error between the theoretical speed and the actual speed of Example 1 of the present application; Figure 7 It is an error diagram of the theoretical path and the actual path of Example 1 of the present application; Figure 8 The theoretical speed curve diagram of the comparative example of this application; Fig. 9 The theoretical path curve diagram of the comparative example of this application; Fig.10 This is an actual speed curve diagram of the comparative example of this application; Fig.11 This is the actual path curve diagram of the comparative example of this application; Fig.12 This is the error diagram of the theoretical speed and the actual speed of the comparative example of this application; Fig.13 This is the error diagram of the theoretical path and the actual path of the comparative example of this application.

[0015] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0016] In order to make the purpose, technical solutions and advantages of this application clearer, the technical solutions in this application will be clearly and completely described below in conjunction with the drawings in this application. Obviously, the described embodiments are part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0017] It can be understood that the radar azimuth antenna fan sweep process includes forward fan sweep and reverse fan sweep, that is, completing one forward fan sweep and one reverse fan sweep is a fan sweep cycle, and the forward fan sweep and the reverse fan sweep are in opposite directions. In order to complete a large-scale fan sweep in a short time, the present invention controls the speed during the forward fan sweep and the reverse fan sweep to suppress the jitter that may be caused by the fast fan sweep, and the specific method is as follows.

[0018] The first embodiment of the present invention provides a radar azimuth antenna fan sweep control method, such as Figure 1 As shown, the specific steps include: Step S1, obtaining the fan scanning range and fan scanning period of the antenna, dividing the fan scanning period into a forward uniform acceleration stage, a forward uniform speed stage, a forward uniform deceleration stage, a reverse uniform acceleration stage, a reverse uniform speed stage, and a reverse uniform deceleration stage, and obtaining the fan scanning time of each stage; Among them, the magnitude of the fan sweep speed in the forward uniform speed stage and the reverse uniform speed stage is the same, and the direction is opposite; the magnitude of the fan sweep acceleration in the forward uniform acceleration stage, the forward uniform deceleration stage, the reverse uniform acceleration stage, and the reverse uniform deceleration stage are the same. Since the directions of the forward fan sweep and the reverse fan sweep are opposite, the directions of the uniform acceleration in the forward uniform acceleration stage and the reverse uniform deceleration stage are the same, and the directions of the acceleration in the forward uniform acceleration stage and the forward uniform deceleration stage are opposite.

[0019] The specific fan scanning time of each stage can be divided according to actual needs.

[0020] Step S2, determine the fan sweep speed in the forward uniform speed stage according to the fan sweep range, the fan sweep time in the forward uniform acceleration stage, the fan sweep time in the forward uniform deceleration stage and the fan sweep time in the forward uniform speed stage; and determine the fan sweep speed in the reverse uniform speed stage.

[0021] Since the forward fan sweep and the reverse fan sweep have the same motion mode and opposite directions, the forward uniform acceleration stage is taken as an example to calculate the fan sweep speed. Multiply by average speed Get the fan sweep range of the forward uniform acceleration stage and the time of the forward uniform deceleration stage Multiply by average speed Get the fan sweep range of the forward uniform deceleration stage and the time of the forward uniform speed stage Multiply by speed The fan sweep range of the forward uniform speed stage is obtained. The sum of the fan sweep ranges of the above stages is the forward fan sweep range, and the following formula can be obtained:

[0022] According to the above formula, the fan sweep speed in the forward uniform speed stage can be obtained:

[0023] In the formula, is the fan sweep range, is the fan sweep time in the forward uniform acceleration stage, is the fan sweep time in the forward uniform speed stage, is the fan sweep time in the positive uniform deceleration stage.

[0024] Step S3, determining the fan sweep acceleration in the forward uniform acceleration stage according to the fan sweep speed; and determining the fan sweep acceleration in the forward uniform deceleration stage, the reverse uniform acceleration stage and the reverse uniform deceleration stage; the acceleration calculation formula is:

[0025] In this embodiment, since the accelerations in each acceleration and deceleration stage are the same but in different directions, the accelerations in other stages can be determined after calculating the fan-sweep acceleration in the forward uniform acceleration stage.

[0026] For example, the fan scanning period is T(4S), and the fan scanning range is A~B, the fan scanning cycle is divided into six stages, and the speed and acceleration of each stage are as follows.

[0027] In the 0~T / 10 stage, that is, the positive uniform acceleration stage, starting from position A, the speed increases from zero to acceleration. Accelerate uniformly to ; In the T / 10~4T / 10 stage, that is, the forward uniform speed stage, Perform uniform motion; in the 4T / 10~T / 2 stage, that is, the forward uniform deceleration stage, the speed is acceleration The machine decelerates uniformly to 0, and moves to position B when the machine decelerates to 0; thus, the positive fan sweep is completed; In the T / 2~6T / 10 stage, that is, the reverse uniform acceleration stage, the speed increases from zero to acceleration. Accelerate uniformly to ; In the 6T / 10~9T / 10 stage, that is, the reverse uniform speed stage, the speed Perform uniform motion; in the 9T / 10~T stage, that is, the reverse uniform deceleration stage, the speed is acceleration The uniform deceleration is performed to 0, and when the deceleration reaches 0, the movement is to position A, thereby completing the reverse fan sweep, that is, completing a fan sweep cycle. The fan sweep range of this embodiment is the fan sweep angle, so the calculated speed is also the angular velocity.

[0028] In this embodiment, the uniform speed segment accounts for 75%, which can ensure stable fan scanning and avoid jitter.

[0029] Step S4, determining the speed of each position point in the forward uniform acceleration stage, the forward uniform deceleration stage, the reverse uniform acceleration stage and the reverse uniform deceleration stage respectively according to the corresponding fan sweep acceleration and fan sweep speed; In this embodiment, according to the speed and acceleration obtained in step S3, the speed of each position point in the forward uniform acceleration stage, the forward uniform deceleration stage, the reverse uniform acceleration stage, and the reverse uniform deceleration stage can be calculated. Since the speed of each position point in the uniform speed stage is the same, the speed of each position point in the uniform speed stage can be directly obtained. A speed curve can be drawn according to the speed of each position point, and the speed curves of the forward uniform acceleration stage, the forward uniform deceleration stage, the reverse uniform acceleration stage, and the reverse uniform deceleration stage are oblique lines.

[0030] Step S5, integrating the speed of all position points within the fan scanning period to obtain continuous position code information; specifically, integrating the above speed curve can obtain the position curve, that is, the control path.

[0031] Step S6, controlling the antenna fan scanning according to the position code information.

[0032] Furthermore, before controlling the antenna fan scan according to the position code information, it is necessary to obtain the current position of the antenna to determine whether it is within the fan scan range. If the current position of the antenna is within the fan scan range, the fan scan is performed directly; if the current position of the antenna is outside the fan scan range, it is considered that the fan scan state is not available, and the radar azimuth turntable is controlled to find the minimum path to quickly control the antenna back to the fan scan range, and then the above control path is input into the PID controller as the azimuth antenna position control signal for closed-loop control.

[0033] It is worth noting that after entering the fan-scan working mode, the boundary of the antenna is no longer judged, so as to avoid the device switching control state back and forth at the boundary due to overshoot, resulting in device instability.

[0034] If a stop command is received during the fan scanning process, the current motion state is maintained to prevent the device from shaking due to an emergency stop, and the antenna is controlled to move at a uniform deceleration until the speed is zero; the zeroing error is determined based on the zero position and current position of the antenna, and the position of the antenna is closed-loop controlled based on the zeroing error to return the antenna to the zero position. The specific position closed-loop control can be achieved in the following ways: the zeroing error is compared with the stability threshold, and when the zeroing error is greater than the stability threshold, the antenna is controlled to move at a uniform speed and approach quickly; and when the zeroing error is less than or equal to the stability threshold, the antenna is controlled to move at a uniform deceleration to the zero position to ensure the safety of the device.

[0035] Example 1 The fan scanning period is T(4S), and the fan scanning range is for - , the fan sweep cycle is divided into six stages, and the speed and acceleration of each stage are as follows: (1) Forward uniform acceleration stage: , acceleration , the speed is accelerated from 0 to , location from Exercise to ; (2) Forward uniform speed stage: ,speed Uniform motion, position from Exercise to ; (3) Forward uniform deceleration stage and reverse uniform acceleration stage: , the speed from Slow down to , acceleration , location from Exercise to Return to ; (4) Reverse uniform speed stage: ,speed Uniform motion, position from Exercise to ; (5) Reverse uniform acceleration stage: , the speed from Accelerate uniformly to 0, acceleration , location from Exercise to .

[0036] According to the above planned speed and path, the curves of ideal (planned) fan sweep speed and fan sweep period are drawn respectively, see Figure 2 , and the curve diagram of the ideal fan sweep position and fan sweep period, see Figure 3 ; According to the above control method, the antenna is controlled by PID to perform fan scanning, and a curve diagram of actual fan scanning speed and fan scanning period is obtained, see Figure 4 , and the curve diagram of the actual fan sweep position and fan sweep period, see Figure 5 ; By comparing the ideal fan-sweep speed and the actual fan-sweep speed, the error is obtained as follows: Figure 6 As shown, the ideal fan scanning position is compared with the actual fan scanning position, and the error is obtained as Figure 7 As shown in the figure, it can be seen that the maximum speed error is 7.25, which meets the accuracy requirement of 5%, and the speed fluctuation is small during commutation, which can effectively suppress the vibration of the equipment. The angle overshoot is 2.18 and the overshoot is 1.8%.

[0037] Comparative Example The fan scanning period is T(4S), and the fan scanning range is for - , the fan-sweep cycle is divided into two stages, and the speed of each stage is as follows: Forward phase: Constant speed , location from Exercise to ; Orientation phase: Constant speed , location from Exercise to .

[0038] According to the above planned speed and path, the ideal fan sweep speed and fan sweep period curves are drawn respectively, see Figure 8 , and the curve diagram of the ideal fan sweep position and fan sweep period, see Fig. 9 ; According to the above control method, the antenna is controlled by PID to perform fan scanning, and a curve diagram of actual fan scanning speed and fan scanning period is obtained, see Fig.10 , and the curve diagram of the actual fan sweep position and fan sweep period, see Fig.11 ; By comparing the ideal fan-sweep speed and the actual fan-sweep speed, the error is obtained as follows: Fig.12 As shown, the ideal fan scanning position is compared with the actual fan scanning position, and the error is obtained as Fig.13 As shown in the figure, it can be seen that the maximum speed error is 45.25° / s. The speed will fluctuate greatly during commutation, which may cause equipment vibration; the angle overshoot is 4.36°, and the overshoot is 3.6%.

[0039] The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A radar azimuth antenna fan scanning control method, characterized in that: include: Obtain the fan scanning range and fan scanning period of the antenna, divide the fan scanning period into a forward uniform acceleration stage, a forward uniform speed stage, a forward uniform deceleration stage, a reverse uniform acceleration stage, a reverse uniform speed stage, and a reverse uniform deceleration stage, and determine the fan scanning time of each stage; Determine the fan sweep speed in the forward uniform speed stage according to the fan sweep range, the fan sweep time in the forward uniform acceleration stage, the fan sweep time in the forward uniform deceleration stage, and the fan sweep time in the forward uniform speed stage; Determine the fan-sweep acceleration in the forward uniform acceleration phase according to the fan-sweep speed; The magnitudes of the fan sweep speeds in the forward uniform speed stage and the reverse uniform speed stage are the same and the directions are opposite; the magnitudes of the fan sweep accelerations in the forward uniform acceleration stage, the forward uniform deceleration stage, the reverse uniform acceleration stage and the reverse uniform deceleration stage are all the same; According to the fan sweep acceleration and fan sweep time of the corresponding stage, the fan sweep speed of all position points within the fan sweep cycle is determined; Integrate the fan-scan speed of all position points within the fan-scan cycle to obtain continuous position code information; The antenna fan scan is controlled according to the position code information.

2. The radar azimuth antenna fan sweep control method according to claim 1, characterized in that: The formula for the fan sweep speed in the forward uniform speed stage is: In the formula, is the fan sweep range, is the fan sweep time in the forward uniform acceleration stage, is the fan sweep time in the forward uniform speed stage, is the fan sweep time in the positive uniform deceleration stage.

3. The radar azimuth antenna fan sweep control method according to claim 1, characterized in that: The fan sweep time of the forward uniform speed stage and the reverse uniform speed stage accounts for 70-80% of the fan sweep cycle.

4. The radar azimuth antenna fan scanning control method according to claim 1, characterized in that: The fan sweep speeds of all positions within the fan sweep cycle include the fan sweep speeds of each position point in the forward uniform acceleration stage, the forward uniform speed stage, the forward uniform deceleration stage, the reverse uniform acceleration stage, the reverse uniform speed stage, and the reverse uniform deceleration stage; The fan sweep speed of each position point in the forward uniform speed stage and the reverse uniform speed stage is the same; The fan sweep speed of each position point in the forward uniform acceleration stage is determined according to the fan sweep acceleration and fan sweep time in the forward uniform acceleration stage; The fan sweep speed of each position point in the forward uniform deceleration stage, the fan sweep speed of each position point in the reverse uniform acceleration stage, and the fan sweep speed of each position point in the reverse uniform deceleration stage are determined in the same way as the fan sweep speed of each position point in the forward uniform acceleration stage.

5. The radar azimuth antenna fan sweep control method according to claim 1, characterized in that: The method also includes controlling the antenna to perform uniform deceleration motion until the speed reaches zero when a stop command is received.

6. The radar azimuth antenna fan sweep control method according to claim 5, characterized in that: After the speed of the antenna is zero, the method further comprises: A zeroing error is determined according to the zero position and the current position of the antenna, and a position closed-loop control is performed on the antenna according to the zeroing error to return the antenna to the zero position.

7. The radar azimuth antenna fan sweep control method according to claim 6, characterized in that: The position closed-loop control comprises: When the zeroing error is greater than a stability threshold, controlling the antenna to move at a uniform speed; When the zeroing error is less than or equal to a stability threshold, the antenna is controlled to perform uniform deceleration motion.

8. The radar azimuth antenna fan sweep control method according to claim 1, characterized in that: Before controlling the antenna fan-sweep according to the position code information, the method further includes: The current position of the antenna is obtained, and when it is determined that the current position of the antenna is outside the fan scanning range, the antenna is controlled to return to the fan scanning range.

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