CN1356561A - Antenna tracking device for robot helicopter and its operation method - Google Patents

Abstract

The invention relates to an antenna tracking device for an unmanned helicopter, which includes a measurement and control antenna, an antenna turntable, remote control and telemetry transceiver equipment, a control computer system, and servo equipment. Wherein, the measurement and control antenna is connected with the remote control telemetry transceiver equipment, the measurement and control antenna is installed on the antenna turntable, the antenna turntable is connected with the control computer system, and the servo equipment is connected with the control interface of the control computer system. Through the control interface program, the device can control the antenna to enter the digital guidance tracking mode, range reckoning or amplitude mode and manual control mode. The device of the invention is simple, efficient, reliable and low in cost, and is suitable for installation and use of a vehicle-mounted mobile ground station.

Description

Antenna tracking device for unmanned helicopter and method of operation thereof

The invention relates to a wireless signal tracking, in particular to an antenna tracking device and an operation method for an unmanned helicopter.

In the remote control telemetry system, considering the problems of low gain, large interference and multipath effect of the omnidirectional antenna, the antenna with directional gain is used in the design. The antenna tracking system is to make the antenna point to the aircraft accurately in real time to obtain the maximum antenna gain. In the antenna tracking system of the UAV, the most commonly used is the tracking antenna of the conical scanning system. It detects the pointing error from the airborne radio frequency signal to correct the antenna pointing. Its accuracy is very high, and the distance used is also It can reach 200km, but the cost is high, the equipment is more complicated, and the concealment is not good.

Considering some particularities of this system, an antenna tracking system based on digital guidance tracking mode is proposed, and at the same time, it is assisted by range reckoning or amplitude tracking mode and manual tracking mode. In the system, according to the characteristics of helicopter flight It can automatically switch modes according to different states to ensure its tracking accuracy. This solution does not require airborne beacons, thereby reducing the weight of airborne equipment and improving the concealment of the aircraft.

The antenna tracking system is an important part of the unmanned helicopter remote control telemetry system. Ensuring the correct tracking direction of the antenna tracking system is a key technical issue for the reliable operation of the remote control telemetry system. Compared with the system of the cone scanning tracking system, the equipment of this system is simple and efficient. , reliable, low cost, and at the same time can meet the performance requirements of the system, and is suitable for the installation and use of vehicle-mounted mobile ground stations.

The object of the present invention is to provide an antenna tracking device for an unmanned helicopter.

Another object of the present invention is to provide a method of operation for antenna tracking of an unmanned helicopter.

The technical scheme of the present invention is achieved in the following way: an antenna tracking device for unmanned helicopters, which includes a measurement and control antenna, an antenna turntable, remote control and telemetry transceiver equipment, a control computer system, servo equipment, etc., wherein the measurement and control antenna is the same as the remote control The telemetry transceiver equipment is connected, the measurement and control antenna is installed on the antenna turntable, the antenna turntable is connected with the control computer system, and the servo equipment is connected to the control interface of the control computer system; the antenna turntable consists of a base, an azimuth axis, an antenna installation rod, a pitch axis, and a pitch axis Composed of worm bracket, left support frame, right support frame, stepping motor, camera mounting frame, fixed plate, and camera, the azimuth axis is installed on the base, one end of the antenna mounting rod is installed on the azimuth axis, and the other end is installed with a measurement and control antenna. The left end of the shaft is connected to the worm gear of the pitch axis, the left support frame, and the camera mounting frame, and the right end of the pitch axis is connected to the right support frame and the pitch axis encoder. The left and right support frames are fixed on the fixed plate, which is connected with the azimuth axis; The running azimuth angle of the azimuth axis is ±720°, the running speed is 20°/s, the angular acceleration is 10°/s ² , and the pitch angle of the pitch axis is -5°～185°; the camera is installed on the camera mounting bracket, and the camera The direction of the measurement and control antenna is consistent with the direction of the measurement and control antenna; the feedback sensor in the antenna turntable is used to read the position data of the azimuth axis and the pitch axis to form a closed-loop control. The feedback sensor is a necessary condition to ensure the tracking accuracy. shaft encoder to complete.

A remote control transmitter and a telemetry receiver are installed in the remote control telemetry transceiver device of the present invention. The high-frequency combination in the remote control telemetry equipment is composed of a low noise amplifier and a power amplifier. The low noise amplifier performs low noise amplification on the weak signal received from the measurement and control antenna, and then transmits it to the telemetry receiver. The power is amplified and transmitted to the receiving system on the unmanned helicopter through the measurement and control antenna.

The control computer system of the present invention is composed of an industrial control computer and a control interface, the control interface is connected to the servo device driver and the feedback sensor conditioning equipment in the antenna turntable; the control computer system is for real-time processing of telemetry and ground station position data, and calculates digital tracking and guidance data , judge the working state, complete the switching of the working state, the monitoring and display of the tracking system, and realize the interactive control between man and machine; the control interface is used to complete the data exchange between the measurement and control antenna, the control computer, the feedback sensor, and the servo equipment .

The measurement and control antenna of the present invention is an S-band angular reflection antenna, the receiving gain is 11-23dBi, the transmitting gain is 11-23dBi, and the lobe angle is 40°-13°.

The servo device of the invention completes the control of the two axial directions of the measurement and control antenna.

An operation method for antenna tracking of an unmanned helicopter according to the present invention, wherein: after the system is powered on, the program will run automatically. At this time, the antenna turntable is controlled to point to the true north by using the up, down, left and right keys of the keyboard Direction and horizontal direction. At this time, the system completes the reading of the reference point, and then can choose the working mode according to the actual situation of the aircraft;

(1) Digital guidance tracking mode, the system reads the azimuth and elevation angles from the ground station. The current position of the antenna can be given by two axial feedback sensors to the control computer through the control interface, and the program compares the current position with the position to be pointed to obtain an error value. The control computer converts this error value into the number of stepping pulses, and sends them to the servo device through the control interface, so that the antenna is correctly pointed to the aircraft. The system will be in this mode state as long as the real-time telemetry is in normal state;

(2) Range reckoning or amplitude tracking mode, once the real-time telemetry signal in the system fails, that is, when the real-time telemetry is in an invalid state, the system will estimate the position of the current aircraft based on the course and speed information of the last aircraft. When in this state, the system can still track the aircraft for a short period of time until the real-time telemetry signal returns to normal. The existence of this mode improves the continuity of system tracking;

(3) Manual control tracking mode, when there is a manual control signal, the system will judge the control of up, down, left and right, so that the servo device will rotate according to the manual control direction. This state is used to manually adjust the system and input the reference point;

When the distance between the aircraft and the ground station is greater than 200 meters, press F1 on the keyboard to start the automatic digital guidance tracking mode. At this time, the antenna system will automatically align with the aircraft. If the real-time telemetry data is abnormal, the system will automatically switch to dead reckoning or In the amplitude tracking mode, the antenna can still be correctly pointed to the aircraft; when the aircraft is less than 200 meters away from the ground station, if the antenna tracking system swings, or there is a serious failure in the real-time telemetry data, the dead reckoning or amplitude tracking mode and the digital guidance tracking mode When it fails, press F2 on the keyboard to start the manual tracking mode. At this time, use the camera to track the aircraft to ensure that the antenna is correctly pointed to the aircraft; when switching to manual tracking mode, press F3 on the keyboard to make the measurement and control antenna point to the north direction , press F4 on the keyboard to make the measurement and control antenna point to the horizontal position, press F5 on the keyboard to make the measurement and control antenna point to the true north direction and the horizontal position at the same time; at any time of system operation, you can use the number keys 1 and 2 on the keyboard , 3 to select, select the appropriate filter system to process the real-time telemetry data of the aircraft, select the number key 1 to indicate that the aircraft has not taken off or is in a hovering state, select the number key 2 to indicate that the aircraft is in a straight-line flight state, select the number key 3 to indicate that the aircraft is in In the hovering state, choosing the correct filtering mode will be more conducive to improving the performance of the antenna tracking system.

The main function of the antenna tracking system is to continuously track the target with a certain accuracy during the flight of the unmanned helicopter, so that the target is always near the center line of the main beam, so as to reliably and continuously receive the telemetry signal with the maximum receiving gain and transmitting gain , Send remote control signal.

In the present invention, the antenna tracking system simplifies the structure of the ground antenna servo system, greatly reduces the complexity of the telemetry ground station, and successfully solves the problems of overhead tracking and short-distance tracking of unmanned helicopters, thereby enabling integrated It is a multi-functional vehicle-mounted mobile ground station integrating unmanned helicopter control platform, antenna servo system and telemetry data monitoring platform.

The present invention will be further described in detail with reference to the accompanying drawings and embodiments.

Fig. 1 is a block diagram of the basic structure of the present invention.

Fig. 2 is a schematic diagram of antenna tracking mode switching in the present invention.

Fig. 3 is a graph showing the relationship between the azimuth angle error and the distance of the aircraft.

Fig. 4 is a graph showing the relationship between pitch angle error and aircraft distance.

Fig. 5 is a schematic diagram of switching displayed on the display of the control computer.

Fig. 6 is a cross-sectional view of the structure of the antenna turntable of the present invention.

In the figure: 1. Base 2. Azimuth axis encoder 3. Azimuth axis 4. Fixed plate 5. Bearing 6. Support block 7. Left support frame 8. Stepper motor 9. Pitch axis worm bracket 10. Camera mounting frame 11. Bearing 12. Bearing 13. Pitch axis worm gear 14. Antenna mounting plate 15. Antenna mounting rod 16. Antenna mounting shaft base 17. Pitch axis 18. Bearing 19. Encoder mounting block 20. Pitch axis encoder 21. Right support frame 22. Support corner block 23. Bearing sleeve 24. Worm gear support tube 25. Bushing 26. Bearing 27. Encoder mounting block 28. Antenna turntable

In the present invention, an antenna tracking device for an unmanned helicopter includes a measurement and control antenna, an antenna turntable 28, remote control and telemetry transceiver equipment, a control computer system, a servo device, etc., wherein the measurement and control antenna is connected with the remote control and telemetry transceiver equipment, and the measurement and control Antenna is installed on the antenna turntable 28, and the antenna turntable 28 is connected with the control computer system, and the servo equipment is connected on the control interface of the control computer system; Shaft worm support 9, left support frame 7, right support frame 21, stepper motor 8, camera installation frame 10, fixed plate 4, camera etc. are formed, azimuth axis 3 is installed on base 1, and antenna installation rod 15 one ends are installed in azimuth On the axis 3, the other end is equipped with a measurement and control antenna, the left end of the pitch axis 17 is connected to the pitch axis worm gear 13, the left support frame 7, and the camera mounting frame 10, and the right end of the pitch axis 17 is connected to the right support frame 21 and the pitch axis encoder 20, The left and right support frames are fixed on the fixed plate 4, and the fixed plate 4 is connected with the azimuth axis 3 of the antenna turntable 28; the azimuth axis 3 in the antenna turntable has an azimuth angle of ±720°, an operating speed of 20°/s, and an angular acceleration of is 10°/s ² , and the pitch angle of the pitch axis 17 is -5°～185°; the camera is installed on the camera mounting frame 10, and the direction of the camera is consistent with the direction of the measurement and control antenna; the feedback sensor in the antenna turntable is used to read The position data of the azimuth axis and the pitch axis are taken to form a closed-loop control. The feedback sensor is a necessary condition to ensure the tracking accuracy, which is mainly completed by using a shaft angle encoder with a certain accuracy.

A remote control transmitter and a telemetry receiver are installed in the remote control telemetry transceiver device of the present invention. The high-frequency combination in the remote control telemetry equipment is composed of a low noise amplifier and a power amplifier. The low noise amplifier performs low noise amplification on the weak signal received from the measurement and control antenna, and then transmits it to the telemetry receiver. The power is amplified and transmitted to the receiving system on the unmanned helicopter through the measurement and control antenna.

The control computer system of the present invention is made up of industrial control computer and control interface, and the control interface is connected to the feedback sensor conditioning equipment in the servo device driver and the antenna turntable; the control computer system is for real-time processing of telemetry and ground station position data, and calculates digital tracking guidance Data, to judge the working state, complete the switching of the working state, monitor and display the tracking system, and realize the interactive control between man and machine; the control interface is used to complete the data of the measurement and control antenna to the control computer, feedback sensor and servo equipment exchange.

The measurement and control antenna of the present invention is an S-band angular reflection antenna, the receiving gain is 11-23dBi, the transmitting gain is 11-23dBi, and the lobe angle is 40°-13°.

The servo equipment in the present invention is used to control the two axes of the measurement and control antenna.

The operation method of the present invention is that after the system is powered on, the program will run automatically. At this time, use the up, down, left and right keys of the keyboard to control the antenna turntable to point to the north direction and the horizontal direction. At this time, the system completes the reading of the reference point. Select work, and then you can choose the working mode according to the actual situation of the aircraft, there are three modes to choose from:

(1) Digital guidance tracking mode, the system reads the azimuth and elevation angles from the ground station. The current position of the antenna can be given by two axial feedback sensors to the control computer through the control interface, and the program compares the current position with the position to be pointed to obtain an error value. The control computer converts this error value into the number of stepping pulses, and sends them to the servo device through the control interface, so that the antenna is correctly pointed to the aircraft. The system will be in this mode state as long as the real-time telemetry is in normal state;

(2) Range reckoning or amplitude tracking mode, once the real-time telemetry signal in the system fails, that is, when the real-time telemetry is in an invalid state, the system will estimate the position of the current aircraft based on the course and speed information of the last aircraft. When in this state, the system can still track the aircraft for a short period of time until the real-time telemetry signal returns to normal. The existence of this mode improves the continuity of system tracking;

(3) Manual control tracking mode, when there is a manual control signal, the system will judge the control of up, down, left and right, so that the servo device will rotate according to the manual control direction. This state is used to manually adjust the system and input the reference point;

When the distance between the aircraft and the ground station is greater than 200 meters, press F1 on the keyboard to start the automatic digital guidance tracking mode. At this time, the antenna system will automatically align with the aircraft. If the real-time telemetry data is abnormal, the system will automatically switch to dead reckoning or The amplitude tracking mode still ensures that the antenna can point to the aircraft correctly; when the aircraft is less than 200 meters away from the ground station, if the antenna tracking system swings, or there is a serious failure in the real-time telemetry data, the dead reckoning or amplitude mode and digital guidance tracking mode will fail , press F2 on the keyboard to start the manual tracking mode. At this time, use the camera to track the aircraft to ensure that the antenna is correctly pointed to the aircraft; when switching to manual tracking mode, press F3 on the keyboard to make the measurement and control antenna point to the north direction. Press F4 on the keyboard to make the measurement and control antenna point to the horizontal position, press F5 on the keyboard to make the measurement and control antenna point to the true north direction and the horizontal position at the same time; at any time of system operation, you can use the number keys 1, 2, 3 Make a selection, select the appropriate filter system to process the real-time telemetry data of the aircraft, select the number key 1 to indicate that the aircraft has not taken off or is in a hovering state, select the number key 2 to indicate that the aircraft is in a straight-line flight state, and select the number key 3 to indicate that the aircraft is in a hovering state state, choosing the correct filtering mode will be more conducive to improving the performance of the antenna tracking system.

In practice, the main error sources of the antenna tracking system with digital guidance as the main tracking method are the position error of the real-time target and the error of the mechanical system.

Firstly, the error caused by the position error of the real-time target to the azimuth angle is discussed. The azimuth angle error is not only related to the positioning error of the target, but also related to the distance of the aircraft. Taking GPS data as the measurement data of the real-time target as an example, the relationship between the azimuth angle error and the distance of the aircraft is shown in Figure 3 (assuming that the GPS positioning is average The square error is 20 meters).

It can be seen from Figure 3 that when the distance of the aircraft is relatively close, there is a large inherent error in the azimuth angle. For example, when the distance of the aircraft is 200 meters, the inherent tracking error of the azimuth angle is 5°. As the distance of the aircraft increases , the inherent error of the azimuth angle will gradually decrease. When the distance of the aircraft reaches 1000 meters, the inherent tracking error of the azimuth angle is 1°.

The error of the pitch angle comes from the error of the aircraft's altitude positioning data. Its error analysis is similar to the error analysis of the azimuth angle. The difference is that the accuracy of the aircraft's low altitude sensor is much higher than that of the position sensor. For higher altitudes , the sensor accuracy has a relatively small influence on the error of the pitch angle. In the altitude measurement system of the unmanned helicopter, we use the following equipment:

(1) Radio altimeter, with a measuring range of 0 to 300 meters and an accuracy of 1 meter;

(2) Barometric altimeter with an accuracy of 20 meters;

(3) GPS height data, accuracy 20 meters.

Therefore, due to the high accuracy of the low-altitude sensor, the pitch angle positioning error is much smaller than the azimuth angle error. The relationship between the pitch angle error and the distance of the aircraft is shown in Figure 4.

It can be seen from Fig. 4 that the inherent error of the pitch angle is always within 2°, and the impact of the error on the communication link is relatively small after using a wide-lobe angular reflection antenna. Therefore, the focus of solving the accuracy problem is to reduce the inherent error of the azimuth angle. We filter the position data of the real-time target to reduce the error of the data.

In the two-dimensional plane, according to the flight characteristics of the unmanned helicopter, we divide its flight trajectory into three main types, and apply different filtering models to them for processing:

(1) Hovering, the aircraft is in this state when it is not taking off, at the beginning of departure, and when it is landing. At this time, the Kalman filter model with a fixed point position can improve the positioning accuracy by nearly an order of magnitude.

(2), straight-line flight, the flight method adopted when the aircraft flies from the take-off point to the mission area, at this time, the Kalman filter model of CA (constant acceleration) or CV (constant velocity) can be used.

(3), circling flight, the flight method adopted by the aircraft in the mission area, at this time, the Kalman filter model of circling flight can be used for data processing.

Using the above method for data processing can not only reduce the real-time position data, but also provide a prediction method for distance reckoning, which improves the accuracy of distance reckoning.

Although there is a certain error in the antenna system during short-distance tracking, at this time, because the aircraft is very close to the ground station, the communication system has a large power margin. According to the lobe pattern of the antenna and the theoretical calculation of the channel of the communication system and the actual experimental results, the allowable error angle of the antenna tracking system when the aircraft is in close range is obtained as follows: distance (m) Allowable error angle (degrees) 50 about 150 100 about 90 200 about 50 It can be seen that the accuracy of the antenna tracking system is higher than the required accuracy. Compared with the position error of the real-time target, the influence of the mechanical system error on the antenna tracking system is reflected at a long distance. The influence of the mechanical system error on the azimuth angle and pitch angle is due to the certain coupling accuracy of the mechanical system. Since the closed-loop control is completed by using the shaft-angle encoder, the error caused by the mechanical system to the antenna tracking system is the accuracy of the shaft-angle encoder, which is less than 1°.

The antenna tracking system mainly has the following tracking modes:

1. Digital guide mode

Extract the real-time target position from the telemetry data, and perform related calculations with the position information of the ground station to obtain the angle of the real-time target relative to the ground station. Then, subtract this angle from the real-time angle obtained by the antenna position sensor to obtain the angle error, and then control the antenna through the interface control circuit and servo equipment to make the angle error zero.

2. Dead reckoning or amplitude mode

Range reckoning or amplitude mode will predict the target position at the current time based on the position data (and sometimes speed data) of the target at the previous time. For the flight with a certain motion model, the Kalman prediction formula can be used, and for the maneuver flight without the model , you can use two-point extrapolation or other maneuvering target tracking methods.

3. Manual control mode

The operator controls the interactive control of the computer, issues instructions for the movement of the antenna, and adjusts the antenna to a certain pointing position to complete the tracking.

Among the above three modes, the digital guidance mode is the basic working state of the system, but for various situations, different tracking modes need to be used. Mode switching can be performed by the operator, or automatically by the computer according to a certain priority. The process of antenna system tracking mode switching is shown in Figure 2.

When the real-time target position is continuously transmitted to the control computer through telemetry data, the antenna tracking system is in the digital guidance tracking mode, and the control computer will obtain the angle error through the data to control the antenna tracking system to complete the tracking pointing.

Due to the influence of communication links and other factors, once the telemetry data is lost, the real-time target position will be lost. Therefore, the system will switch to range reckoning or amplitude mode to predict the target position at this moment and maintain the continuity of tracking, that is Through the prediction of data, it avoids the decrease of tracking accuracy caused by data loss.

The error of range reckoning or amplitude mode is related to the flight state of the aircraft. When the aircraft meets a certain flight model, the error of range reckoning or range is small, but when the aircraft is in maneuvering flight, the error of range reckoning or range increases with time. rapidly increased over time. Therefore, when the distance reckoning or amplitude exceeds a certain period of time, and the error caused by it can no longer meet the requirements, the system will switch to manual control mode to avoid tracking the lost target and give an alarm indication at the same time. Through experimental data and theoretical calculations, we give the time of range calculation or amplitude under various states as: state Dead reckoning or amplitude time (seconds) hover or not take off 130 maneuver flight 30 circling flight 60

The antenna tracking system is an important part of the remote control telemetry system of the unmanned helicopter, and the normal operation of the antenna tracking system also directly affects the work of the remote control telemetry system. Once the antenna tracking system loses tracking, it will directly lead to the interruption of the communication link of the remote control telemetry system. As a result, the ground station cannot obtain the real-time status of the aircraft and control the aircraft, and the antenna tracking system will not be able to obtain the real-time position of the aircraft through telemetry data. data, leading to a vicious circle. Therefore, corresponding measures must be taken to avoid entering such a loop, and it is very important to ensure the reliability of the antenna tracking system.

In order to solve the above problems, the antenna tracking system adopts the abnormal data processing method to ensure the reliability of the antenna tracking system. The processing of abnormal data is mainly based on eliminating outliers, not only from the statistical information of the data, but also taking into account the flight characteristics of the helicopter. For the data processing of unmanned helicopter orientation, different filtering models can be used for the above three flight models. Using different models for different flight states can better improve the ability of outlier elimination. Regarding the abnormal data processing using the filtering model Threshold selection and calculation of false alarm probability. For the data processing of unmanned helicopter altitude, it should also be divided into two parts, namely stable altitude flight and maneuvering climbing (landing) flight. The fixed-value Kalman filter processing method and the corresponding outlier elimination method can be used for stable altitude flight, and the CA or CV Kalman filter model can be used for maneuver climbing (landing) flight.

The adoption of the above measures ensures the reliability of the antenna tracking system.

In view of the flight characteristics of unmanned helicopters, there are still two problems to be dealt with in the antenna tracking system:

(1) Overhead tracking problem. Overhead flight is a relatively special flight state for unmanned helicopters. In order to ensure that the antenna tracking system can still point correctly and ensure the tracking speed during the overhead flight, the design method of the antenna base is adopted to make the pitch angle Complete control from -5° to 185°. In addition, the tracking algorithm ensures that the antenna system will control the rotation of the pitch axis during overhead tracking, so as to avoid tracking delay caused by controlling the 180-degree rotation of the azimuth axis.

(2) Short distance tracking antenna swing problem. In the previous discussion, due to the relatively large error in the azimuth angle at close range, and the error is randomly distributed, if it is not processed, the antenna will swing when the aircraft is in close range. In order to avoid this state, we relax the tracking error at short distances, that is, different error thresholds are used depending on the distance of the aircraft. Once the error of the antenna tracking system exceeds the error threshold, it will be corrected. The choice of the error threshold depends on factors such as the lobe pattern of the antenna, the power margin of the communication system, and the amount of swing when it is not processed. In this system, the error threshold is selected as follows: distance (m) Error Threshold (degrees) <100 10 100～500 5 500～1000 2 >1000 1

In ground mooring experiments and flight tests, using this method, the performance of close-range tracking is completely normal, and the swing of the antenna is greatly reduced.

Claims (17)

1. An antenna tracking device for unmanned helicopters, characterized in that it includes a measurement and control antenna, an antenna turntable, a remote control telemetry transceiver, a control computer system, and a servo device. The measurement and control antenna is connected with the remote control telemetry transceiver, and the measurement and control antenna Installed on the antenna turntable, the antenna turntable is connected with the control computer system, and the servo equipment is connected with the control interface of the control computer system. 2. The device according to claim 1, characterized in that: the antenna turntable consists of base (1), azimuth axis (3), antenna installation rod (15), pitch axis (17), pitch axis worm support (9), Left support frame (7), right support frame (21), stepper motor (8), camera installation frame (10), fixed plate (4), camera composition, azimuth axis (3) is installed on the base (1), One end of the antenna installation rod (15) is installed on the azimuth shaft (3), and the other end is equipped with a measurement and control antenna, and the left end of the pitch shaft (17) is connected with the pitch shaft worm gear (13), the left support frame (7), the camera mount ( 10), the right end of the pitch axis (17) is connected to the right support frame (21) and the pitch axis encoder (20), the left and right support frames are fixed on the fixed plate (4), and the fixed plate (4) is connected with the azimuth axis (3) . 3. The device according to claim 1, characterized in that: the azimuth axis (3) in the antenna turntable operates at an azimuth angle of ±720°, at an operating speed of 20°/s, at an angular acceleration of 10°/s ² , and The pitch angle of the axis is -5°～185°. 4. The device according to claim 1, 2, characterized in that: the camera is installed on the camera mounting frame (10), and the direction of the camera is consistent with the direction of the measurement and control antenna. 5. The device according to claims 1 and 2, characterized in that: the feedback sensor in the antenna turntable is used to read the position data of the azimuth axis and the pitch axis to form a closed-loop control, and the feedback sensor is a necessary condition to ensure the tracking accuracy. It is mainly done by using a shaft angle encoder with certain precision. 6. The device according to claim 1, characterized in that: a remote control transmitter and a telemetry receiver are installed in the remote control telemetry transceiver. 7. The device according to claim 1, characterized in that: the high-frequency combination in the remote control and telemetry equipment is composed of a low-noise amplifier and a power amplifier, and the low-noise amplifier performs low-noise amplification on the weak signal received from the measurement and control antenna, and then It is transmitted to the telemetry receiver, and the power amplifier amplifies the power of the signal output by the remote control transmitter, and transmits it to the receiving system on the unmanned helicopter through the measurement and control antenna. 8. The device according to claim 1, characterized in that: the control computer system is composed of an industrial control computer and a control interface, and the control interface is connected to the servo device driver and the feedback sensor conditioning equipment in the antenna turntable. 9. The device according to claim 1, characterized in that: the control computer system processes telemetry and ground station position data in real time, calculates digital tracking and guidance data, judges the working state, and completes the switching and tracking system of the working state monitor, display, and realize interactive control between man and machine. 10. The device according to claim 1, 8, characterized in that: the control interface is used to complete the data exchange between the measurement and control antenna, the control computer, the feedback sensor and the servo equipment. 11. The device according to claim 1, characterized in that: the measurement and control antenna is an S-band angular reflection antenna, the receiving gain is 11-23dBi, the transmitting gain is 11-23dBi, and the lobe angle is 40°-13°. 12. The device according to claim 1, characterized in that: the servo equipment controls the two axes of the measurement and control antenna. 13. An operation method for antenna tracking of unmanned helicopters, which is characterized in that: after the system is powered on, the program will run automatically. North direction and horizontal direction. At this time, the system completes the reading of the reference point, and then can choose the working mode according to the actual situation of the aircraft. (1) Digital guidance tracking mode, the system reads the azimuth and elevation angle from the ground station, the current position of the measurement and control antenna can be given to the control computer by the two axial feedback sensors through the control interface, and the program compares the current position with the Comparing the position to point to get an error value, the control computer converts this error value into the number of step pulses, and sends it to the servo device through the control interface, so that the antenna is correctly pointed to the aircraft. As long as the real-time telemetry is in a normal state, the system will be in this mode state; (2) Range reckoning or amplitude tracking mode, once the real-time telemetry signal in the system fails, that is, when the real-time telemetry is in an invalid state, the system will estimate the current position of the aircraft based on the last flight course and speed information. When in this state, The system can still track the aircraft in a short period of time until the real-time telemetry signal returns to normal. The existence of this mode improves the continuity of system tracking; (3) Manual control tracking mode. When the manual control signal is used, the system will judge the control of up, down, left and right, so that the servo equipment will rotate according to the manual control direction. This state is used for manual adjustment and benchmarking of the system point input. 14. The operation method according to claim 13, characterized in that: when the distance between the aircraft and the ground station is greater than 200 meters, press F1 on the keyboard to start the automatic digital guidance tracking mode, at this time the antenna system will automatically align with the aircraft, If the real-time telemetry data is abnormal, the system will automatically switch to range reckoning or amplitude tracking mode, still ensuring that the antenna can be correctly pointed to the aircraft. 15. The operation method according to claim 13, characterized in that: when the distance of the aircraft from the ground station is less than 200 meters, if the antenna tracking system swings, or there is a serious failure in the real-time telemetry data, the distance reckoning or amplitude tracking mode and digital guidance When the tracking mode fails, press F2 on the keyboard to start the manual tracking mode, use the camera to track the aircraft, and ensure that the measurement and control antenna is correctly pointed to the aircraft. 16. The operation method according to claim 13, characterized in that: when switching to the manual tracking mode, press F3 on the keyboard to make the measurement and control antenna point to the north direction, press F4 on the keyboard to make the measurement and control antenna point to the horizontal Direction position, press F5 on the keyboard to make the measurement and control antenna point to the true north direction and the horizontal direction position at the same time. 17. The operation method according to claim 13, characterized in that: at any time of system operation, you can use the number keys 1, 2, 3 on the keyboard to select an appropriate filter system to process the real-time telemetry of the aircraft Data, select the number key 1 to indicate that the aircraft has not taken off or is in a hovering state, select the number key 2 to indicate that the aircraft is in a straight-line flight state, select the number key 3 to indicate that the aircraft is in a hovering state, and select the correct filter mode, which will be more conducive to improving antenna tracking system performance.

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