Antenna device for tracking and capturing unmanned aerial vehicle and tracking and capturing method

Abstract

The invention provides an antenna device for tracking and capturing an unmanned aerial vehicle and a tracking and capturing method, and belongs to the technical field of antennas. The invention provides a technology for quickly and effectively recapturing the lost target unmanned aerial vehicle, thereby greatly improving the viability of the unmanned aerial vehicle on the sea, avoiding the loss of the unmanned aerial vehicle, further prolonging the time of information communication, and guaranteeing the long-time communication between a ship and the unmanned aerial vehicle.

Description

Technical Field

[0001] The present invention belongs to the technical field of antennas, and in particular relates to an antenna device and a tracking and capturing method for tracking and capturing a drone. Background Art

[0002] With the advancement of science and technology and the needs of practical applications, the application of drones is becoming more and more extensive. The data link between drones and ships, as the "nerve center" of the drone system, is responsible for the task of sending and receiving data. The drone system is an important part of the drone system, which is used to realize the remote control, telemetry, tracking and positioning of drones and information transmission.

[0003] With the further increase of deep-sea operations, such as deep-sea fishing, drones will play a huge role in future deep-sea operations and have an important position. Whether the communication connection between ships and drones is reliable not only determines whether the data transmission is smooth, but also determines whether the drone can land safely. Therefore, it is of great significance to study stable and efficient methods suitable for marine environments that can enable drones to complete their assigned tasks safely and efficiently. Summary of the invention

[0004] In view of this, the present invention has the characteristics of simple structural design and high reliability, and focuses on proposing a technology for quickly and effectively recapture a target (UAV) after it is lost, which greatly improves the survivability of the UAV at sea and avoids the loss of the UAV. At the same time, it also further increases the duration of information communication and ensures long-term communication between the ship and the aircraft.

[0005] The present invention adopts the following technical solutions to achieve the above technical effects:

[0006] An antenna device for tracking and capturing a drone, comprising an antenna mount and an antenna surface mounted on the antenna mount, and also comprising a servo control system mounted on the antenna mount, wherein the servo control system comprises an in-cabin device and an out-cabin device;

[0007] The equipment in the cabin includes a host computer and a receiver. The host computer controls the antenna device, monitors the status and can perform human-computer interaction. The receiver receives the intermediate frequency signal, demodulates the error voltage and provides it to the antenna control unit to achieve stable pointing of the antenna to the drone.

[0008] The extravehicular equipment includes a high-precision measurement unit, an antenna control unit, an azimuth axis zeroing switch, a gyroscope, and a radio frequency front end; the high-precision measurement unit is used to measure and output the ship's heading, roll, pitch, longitude, and latitude data; the antenna control unit is the central nervous system for antenna pointing tracking, which realizes the integrated processing of multiple data and calculates and outputs the pointing angles of each axis; the azimuth axis zeroing switch realizes the angle calibration of the azimuth axis after power-on; the gyroscope is used to sense and output the spatial motion rate of the azimuth axis and pitch axis; the radio frequency front end realizes the down-conversion of the radio frequency signal;

[0009] The default working mode of the antenna device is program-guided. The host computer calculates the geographic angle of the target drone based on the longitude, latitude, and altitude information of the target drone, as well as the longitude and latitude information of the antenna, and sends it to the antenna control unit as the target geographic angle. The antenna control unit then combines the ship's heading, roll, and pitch information output by the high-precision measurement unit to finally calculate the target deck angle corresponding to the drone's location, and then drives the antenna through each axis drive and the execution motor to keep the antenna pointing to the target drone at all times;

[0010] When the antenna device is measuring the target position or the program guidance does not meet the pointing accuracy requirements, it switches to automatic tracking, so that the antenna azimuth axis works in a single pulse tracking state according to the azimuth axis error voltage reported by the receiver, and the pitch axis works in a program guidance state according to the pitch axis target geographic angle calculated and output by the host computer. During the movement of the target UAV, the rate of change of its position in the pitch direction is much smaller than that in the azimuth direction. At the same time, since the antenna surface is a rectangular surface, its beam width in the pitch direction is wider than that in the azimuth direction. Considering the above, the pitch axis always maintains the program guidance working mode to effectively track the target UAV. However, the beam width in the azimuth direction is narrow and the target UAV moves quickly. In order to further improve the tracking accuracy in this direction, it is necessary to introduce a single pulse tracking mode into the azimuth axis working mode. The single pulse tracking mode is a fully closed-loop tracking mode, which can avoid the influence of the above-mentioned factors. The ultimate goal is to point the antenna to the target UAV with high precision, and finally achieve the precise pointing of the antenna to the target UAV;

[0011] The azimuth-axis motor and pitch-axis motor of the antenna mount are both equipped with encoders. The encoder provides the actual pointing position information of the antenna mount to the antenna control unit, and compares it with the theoretical pointing position information calculated by the antenna control unit itself or the theoretical pointing position information sent by the host computer, and sends an angular error signal to the drive component. The drive component drives the pitch motor and azimuth motor to rotate the antenna in the direction that reduces the error.

[0012] Furthermore, the antenna control unit realizes the pointing of the antenna to the drone as follows:

[0013] The position of the UAV in the geocentric coordinate system is calculated through coordinate transformation;

[0014] Assume that the longitude of the drone is λ0, the latitude is φ0, and the height is h; the longitude of the antenna is λ, the latitude is φ, and the antenna height is 0; the radius of the earth is R, and the distance between the drone and the antenna is L;

[0015] The coordinate calculation formula of the drone in the geocentric coordinate system is:

[0016]

[0017] In the formula,

[0018] Xt1——x-axis coordinate of the drone in the geocentric coordinate system;

[0019] Yt1——Y-axis coordinate of the drone in the geocentric coordinate system;

[0020] Zt1——z-axis coordinate of the drone in the geocentric coordinate system;

[0021] Rt——the distance between the drone and the center of the earth;

[0022] R——radius of the Earth;

[0023] L——UAV altitude;

[0024] φ0——UAV longitude;

[0025] λ0——UAV latitude;

[0026] The coordinate calculation formula of the drone in the geographic coordinate system is:

[0027]

[0028] In the formula,

[0029] Xt1——x-axis coordinate of the drone in the geocentric coordinate system;

[0030] Yt1——Y-axis coordinate of the drone in the geocentric coordinate system;

[0031] Zt1——z-axis coordinate of the drone in the geocentric coordinate system;

[0032] E——pitch angle of the drone in the geographic coordinate system;

[0033] A——the azimuth angle of the drone in the geographic coordinate system;

[0034] L——UAV altitude.

[0035] Furthermore, the high-precision measurement unit is an INS / GNSS combined navigation unit composed of an inertial navigation system and dual GPS / BD receivers; the inertial navigation system is an attitude solution unit with three fiber optic gyroscopes and three quartz flexible accelerometers as measuring devices and a DSP as the computing core.

[0036] A method for capturing a drone using an antenna is implemented by an antenna device for tracking and capturing a drone as described in the claims; specifically as follows:

[0037] During the process of establishing communication between the drone and the antenna, the drone sends the real-time position information of the drone to the antenna, and also sends the drone's flight time information, to ensure that after a long period of failure to establish communication, both parties agree to move to the same area so that communication can be established eventually;

[0038] After the communication is interrupted, the drone sends a single carrier signal at the lowest frequency in the communication band to increase the beam width and facilitate successful antenna capture.

[0039] Furthermore, there are two situations in which communication is interrupted. In one situation, when a drone passes directly above the antenna, communication is interrupted due to the influence of the antenna's zenith blind spot. The drone is allowed to keep flying straight, and the antenna is pointed to a position where the drone may exit the blind spot in the future and wait until the drone flies out of the antenna blind spot and communication is reestablished.

[0040] Another situation is the communication interruption when the UAV is not passing directly over the antenna. After the communication is interrupted, let the UAV hover at the lost point, and the search order of the antenna should be from the center wave position of the search map to search gradually outward.

[0041] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0042] The structural design is simple and adopts a two-axis frame form to improve the system's working reliability;

[0043] The antenna control unit has the function of autonomously calculating the azimuth of the target drone, thus ensuring that the antenna can still stably point to the target when the host computer fails, thereby improving the safety redundancy of the system;

[0044] By introducing the technology of rapid recapture of the target drone after it is lost, the maximum and longest communication between the ship and the aircraft can be guaranteed. More importantly, it can prevent the drone from crashing into the sea, saving system costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 It is a schematic diagram of the structure of the antenna system of the present invention;

[0046] Figure 2 It is a structural diagram of the mount of the antenna of the present invention;

[0047] Figure 3 It is a composition diagram of the antenna servo system of the present invention;

[0048] Figure 4 It is a composition diagram of the antenna control loop of the present invention;

[0049] Figure 5 It is a schematic diagram of the search range and path of the ship-borne antenna of the present invention.

[0050] In the figure: 1. Antenna surface, 2. Slip ring, 3. Inertial navigation, 4. Azimuth straight cylinder, 5. Counterweight, 6. Pitch box, 7. Left support arm, 8. Azimuth drive device, 9. Right support arm, 10. Pitch drive device. DETAILED DESCRIPTION

[0051] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0052] Reference Figures 1 to 5 ,This paper proposes a shipborne UAV system design idea, ,which is discussed from four aspects of structure design, servo design, pointing algorithm and loss recapture.

[0053] 1) Structural design

[0054] The antenna in the present invention is composed of an antenna surface and an antenna seat, wherein the antenna surface adopts a rectangular array antenna, and the antenna seat adopts an AE two-axis mount, the A axis can rotate continuously 360 degrees, and the E axis rotation angle range is -10 degrees to +90 degrees.

[0055] The antenna base consists of a pitch device and an azimuth device, with a total weight of approximately 80Kg.

[0056] The azimuth device consists of an azimuth support tube, a slip ring, an inertial navigation system, etc.

[0057] The pitch device consists of a pitch box, left and right arms, an azimuth drive device, a pitch drive device, a counterweight, etc.

[0058] Since the antenna is preferentially tracked by program guidance during use, if the structural error is large, it will affect the tracking accuracy; when the antenna is used for target position measurement, a large azimuth error will affect the target measurement value. For the above reasons, the antenna structural error needs to be calibrated.

[0059] Traditional error calibration methods require the use of more measuring instruments and take up a lot of manpower and time costs, and are not suitable for batches of small antennas.

[0060] The basic principle of dynamic pointing error calibration is to install the antenna on a swing stage to track the target when the target geographical angle is known, measure the swing stage attitude through high-precision inertial navigation, measure multiple groups of AE axis angles by changing the swing stage attitude, and calculate the system error using the least squares method.

[0061] The AE antenna structure system error is shown in Table 1:

[0062] Table 1 AE antenna structure system error

[0063]

[0064] 2) Servo design

[0065] The servo system consists of in-cabin equipment and out-cabin equipment. The in-cabin equipment includes a distribution box, a host computer, a receiver and a power supply unit; the out-cabin equipment includes a high-precision measurement unit, a slip ring, a CAN junction box, an ACU, an azimuth axis zero switch, an azimuth axis drive, an azimuth axis motor, a gyroscope, a pitch axis drive, a pitch axis motor, a RF front end, an upper limit switch and a lower limit switch of the pitch axis.

[0066] The distribution box realizes 220V AC output, which is the total power supply of the system;

[0067] The host computer realizes system status monitoring and equipment control, and is a human-computer interaction tool;

[0068] The receiver receives the intermediate frequency signal, demodulates the error voltage and provides it to the ACU, so that the antenna can be stably pointed at the drone.

[0069] The power supply unit converts AC 220V into DC 24V and supplies power to related back-end equipment;

[0070] The high-precision measurement unit measures and outputs the ship's heading, roll, pitch, longitude, and latitude data;

[0071] The slip ring ensures that the RF link is not interrupted when the antenna azimuth axis rotates continuously 360 degrees;

[0072] The CAN junction box mainly plays an integrating role and can effectively mount multiple CAN node devices;

[0073] ACU is the central nervous system of antenna pointing and tracking, realizing the integrated processing of multiple data and calculating and outputting the pointing angles of each axis;

[0074] The azimuth axis zero switch realizes the angle calibration of the azimuth axis after power-on;

[0075] The azimuth axis drive and the azimuth axis motor realize the effective movement of the azimuth axis under the joint action of the drive and the motor;

[0076] The gyro sensor outputs the spatial motion rate of the azimuth axis and the pitch axis;

[0077] The pitch axis drive and the pitch axis motor realize the effective movement of the pitch axis under the joint action of the drive and the motor;

[0078] The RF front end realizes down-conversion of RF signals, facilitating long-distance signal transmission;

[0079] The upper and lower limit switches of the pitch axis not only limit the over-limit movement of the pitch axis, but also have the function of calibrating the angle of the pitch axis after power-on.

[0080] The system working modes are designed as follows: manual control, command position, standby, automatic tracking, and program guidance.

[0081] Manual control: You can specify the azimuth axis (or pitch axis) to rotate at a specified direction and speed;

[0082] Command position: Control the rotation of the two axes of the antenna to fix the antenna's geographic pointing direction at the azimuth and elevation geographic angles given by the command;

[0083] Standby: The antenna azimuth and pitch axis motors are disabled;

[0084] Automatic tracking: Make the antenna azimuth axis work in the single pulse tracking state according to the azimuth axis error voltage, and make the elevation axis work in the program guidance state according to the digital guidance angle;

[0085] Program guidance: Calculate the geographic angle of the target UAV based on the longitude, latitude, and altitude information of the target UAV, as well as the local longitude and latitude information of the ship, and use this as the target geographic angle to control the antenna to always point to the target UAV.

[0086] The default working mode of the antenna is program guidance. It switches to automatic tracking when measuring the target position or when program guidance does not meet the tracking accuracy requirements.

[0087] The servo control system is a feedback closed-loop control system that works on position error. The servo system is required to have characteristics such as fast response, high tracking accuracy and wide speed regulation range, and the equipment is required to work under dynamic conditions on board. Therefore, the servo control system consists of three feedback closed-loop control loops: current, speed and position.

[0088] In the servo control system, the current loop and speed loop are designed in the driver, and the position loop control is completed by the controller. The guide position is compared with the actual position of the antenna to obtain the angle error signal and send it to the driver. The driver drives the motor to rotate the antenna in the direction of reducing the error.

[0089] Since the main working mode of the antenna is program-guided, the pointing accuracy of the antenna in this working mode is highly dependent on the precision and accuracy of the output data of the high-precision measurement unit. In order to improve the pointing accuracy of the antenna system, the high-precision measurement unit used in the servo system is an INS / GNSS combined navigation system composed of an inertial navigation system and dual GPS / BD receivers. The inertial navigation system (hereinafter referred to as inertial navigation) is a high-precision attitude solution unit with three fiber optic gyroscopes and three quartz flexible accelerometers as measurement devices and DSP as the computing core. By combining with the positioning and orientation information of the dual GPS / BD receivers, the heading attitude drift of the simple inertial navigation can be overcome to achieve high-precision angle output.

[0090] 3) Pointing algorithm

[0091] Antenna pointing is to calculate the position of the UAV in the geographic coordinate system through coordinate transformation based on the position of the UAV in the geocentric coordinate system.

[0092] Assume that the longitude of the UAV is λ0, the latitude is φ0, and the altitude is h; the longitude of the antenna is λ, the latitude is φ, and the altitude is 0 (the antenna is installed on the ship); the radius of the earth is R, and the distance between the UAV and the antenna is L.

[0093] The coordinate calculation formula of the drone in the geocentric coordinate system is:

[0094]

[0095] In the formula,

[0096] Xt1——x-axis coordinate of the drone in the geocentric coordinate system;

[0097] Yt1——Y-axis coordinate of the drone in the geocentric coordinate system;

[0098] Zt1——z-axis coordinate of the drone in the geocentric coordinate system;

[0099] Rt——the distance between the drone and the center of the earth;

[0100] R——radius of the Earth;

[0101] L——UAV altitude;

[0102] φ0——UAV longitude;

[0103] λ0——UAV latitude.

[0104] The coordinate calculation formula of the drone in the geographic coordinate system is:

[0105]

[0106] In the formula,

[0107] Xt1——x-axis coordinate of the drone in the geocentric coordinate system;

[0108] Yt1——Y-axis coordinate of the drone in the geocentric coordinate system;

[0109] Zt1——z-axis coordinate of the drone in the geocentric coordinate system;

[0110] E——pitch angle of the drone in the geographic coordinate system;

[0111] A——the azimuth angle of the drone in the geographic coordinate system;

[0112] L——UAV altitude.

[0113] 4) Lost and recaptured

[0114] When a ship-borne antenna is tracking a UAV, once the communication between the ship and the UAV is interrupted, the ship-borne antenna will not be able to know the spatial position of the UAV. If the communication interruption lasts for a long time, the UAV may be completely disconnected and eventually fall into the sea. The present invention proposes a method for quickly recapture a target after the ship-borne antenna loses it.

[0115] In order to solve the above problems, during the process of establishing communication between the UAV and the ship, in addition to sending the UAV's real-time position information to the ship, the UAV also sends the UAV's flight time information to the ship, to ensure that if communication cannot be established for a long time, both parties agree to move to the same area so that communication can be finally established, thereby avoiding the UAV falling into the sea.

[0116] Once communications are interrupted, cooperation between the ship and the drone is required to increase the probability of the drone being recaptured.

[0117] Once the communication is interrupted, the drone antenna sends a single carrier signal at the lowest frequency in the communication band to increase the beam width, making it easier for the shipborne antenna to capture successfully.

[0118] There are two situations in which communication is interrupted. One is when the drone passes directly above the antenna, and the communication is interrupted due to the influence of the antenna's zenith blind spot. The drone is allowed to fly straight, and the antenna is pointed to the position where the drone may be out of the blind spot in the future, waiting until the drone flies out of the antenna blind spot and re-establishes communication. The timing function is started when the drone enters the zenith blind spot and communication is interrupted. If the target drone cannot be captured for 10 minutes, it is considered that the target is completely lost, the antenna's blind waiting is interrupted, and the wide-range search mode is switched to.

[0119] Another situation is the communication interruption when the UAV is not passing directly over the antenna. After the communication is interrupted, let the UAV hover at the lost point, and the search order of the antenna should be from the center wave position of the search map to search gradually outward.

[0120] It is not the case that the larger the search range, the higher the capture probability. Blindly expanding the search range will often cause the search cycle to become longer, resulting in the inability to quickly achieve capture. Therefore, the search range should be designed based on the search cycle and the probability of discovery. The ripple center distance in the present invention is the half-power beam width. times.

[0121] During the process of establishing communication between the drone and the antenna, the drone sends the real-time position information of the drone to the antenna, and also sends the drone's flight time information, to ensure that after a long period of failure to establish communication, both parties agree to move to the same area so that communication can be established eventually;

[0122] If communication between the ship and the drone has not been established, when the drone's flight time is only half an hour left, the ship and the drone will sail simultaneously to the position of the ship before the communication was interrupted, in order to finally detect the drone and establish communication with the help of the ship's omnidirectional antenna.

[0123] After the communication is interrupted, the drone sends a single-carrier signal at the lowest frequency in the communication band to increase the beam width and facilitate successful antenna capture;

[0124] The receiver adds a "pre-lock" status report. When the antenna is aligned with the drone signal sidelobe, the receiver reports the pre-lock status to the antenna control unit, thereby informing the antenna control unit that the antenna is now pointing close to the target drone.

[0125] The wide range search mode starts with a certain elevation angle and a certain gradient (usually half-power beam width). The working mode of conducting a large-scale search of the airspace in a decreasing manner (times). For each pitch angle, the azimuth performs a 360° rapid circular motion. If the target drone is not found (the receiver does not report the "pre-lock" status), the pitch angle is reduced by a certain amount to make the azimuth perform a 360° rapid circular motion again; if the target drone is found (the receiver reports the "pre-lock" status), it will enter a small-scale search mode, that is, fix the pitch angle, and let the azimuth axis perform a precise search within 5° to the left and right of the azimuth geographic pointing, until the receiver reports the status from "pre-lock" to "lock", thereby achieving accurate capture of the target drone.

[0126] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. An antenna device for tracking and capturing a drone, comprising an antenna mount and an antenna surface mounted on the antenna mount, characterized in that: Also included is a servo control system mounted on the antenna mount, the servo control system including in-cabin equipment and out-cabin equipment; The equipment in the cabin includes a host computer and a receiver. The host computer controls the antenna device, monitors the status and can perform human-computer interaction. The receiver receives the intermediate frequency signal, demodulates the error voltage and provides it to the antenna control unit to achieve stable pointing of the antenna to the drone. The extravehicular equipment includes a high-precision measurement unit, an antenna control unit, an azimuth axis zeroing switch, a gyroscope, and a radio frequency front end; the high-precision measurement unit is used to measure and output the ship's heading, roll, pitch, longitude, and latitude data; the antenna control unit is the central nervous system for antenna pointing tracking, which realizes the integrated processing of multiple data and calculates and outputs the pointing angles of each axis; the azimuth axis zeroing switch realizes the angle calibration of the azimuth axis after power-on; the gyroscope is used to sense and output the spatial motion rate of the azimuth axis and pitch axis; the radio frequency front end realizes the down-conversion of the radio frequency signal; The default working mode of the antenna device is program-guided. The host computer calculates the geographic angle of the target drone based on the longitude, latitude, and altitude information of the target drone, as well as the longitude and latitude information of the antenna, and sends it to the antenna control unit as the target geographic angle. The antenna control unit then combines the ship's heading, roll, and pitch information output by the high-precision measurement unit to finally calculate the target deck angle corresponding to the drone's location, and then drives the antenna through each axis drive and the execution motor to keep the antenna pointing to the target drone at all times; When the antenna device is measuring the target position or the program guidance does not meet the pointing accuracy requirements, it switches to automatic tracking, so that the antenna azimuth axis works in a single pulse tracking state according to the azimuth axis error voltage reported by the receiver, and the pitch axis works in a program guidance state according to the pitch axis target geographic angle calculated and output by the host computer. During the movement of the target UAV, the rate of change of its position in the pitch direction is much smaller than that in the azimuth direction. At the same time, since the antenna surface is a rectangular surface, its beam width in the pitch direction is wider than that in the azimuth direction. Considering the above, the pitch axis always maintains the program guidance working mode to effectively track the target UAV. However, the beam width in the azimuth direction is narrow and the target UAV moves quickly. In order to further improve the tracking accuracy in this direction, it is necessary to introduce a single pulse tracking mode into the azimuth axis working mode. The single pulse tracking mode is a fully closed-loop tracking mode, which can avoid the influence of the above-mentioned factors. The ultimate goal is to point the antenna to the target UAV with high precision, and finally achieve the precise pointing of the antenna to the target UAV; The azimuth-axis motor and pitch-axis motor of the antenna mount are both equipped with encoders. The encoder provides the actual pointing position information of the antenna mount to the antenna control unit, and compares it with the theoretical pointing position information calculated by the antenna control unit itself or the theoretical pointing position information sent by the host computer, and sends an angular error signal to the drive component. The drive component drives the pitch motor and azimuth motor to rotate the antenna in the direction that reduces the error.

2. The antenna device for tracking and capturing a drone according to claim 1, characterized in that: The antenna control unit realizes the pointing of the antenna to the drone, as follows: The position of the UAV in the geocentric coordinate system is calculated through coordinate transformation; Assume that the longitude of the drone is λ0, the latitude is φ0, and the height is h; the longitude of the antenna is λ, the latitude is φ, and the antenna height is 0; the radius of the earth is R, and the distance between the drone and the antenna is L; The coordinate calculation formula of the drone in the geocentric coordinate system is: Rt=R+LIn the formula, Xt1——x-axis coordinate of the drone in the geocentric coordinate system; Yt1——Y-axis coordinate of the drone in the geocentric coordinate system; Zt1——z-axis coordinate of the drone in the geocentric coordinate system; Rt——the distance between the drone and the center of the earth; R——radius of the Earth; L——UAV altitude; φ0——UAV longitude; λ0——UAV latitude; The coordinate calculation formula of the drone in the geographic coordinate system is: In the formula, Xt1——x-axis coordinate of the drone in the geocentric coordinate system; Yt1——Y-axis coordinate of the drone in the geocentric coordinate system; Zt1——z-axis coordinate of the drone in the geocentric coordinate system; E——pitch angle of the drone in the geographic coordinate system; A——the azimuth angle of the drone in the geographic coordinate system; L——UAV altitude.

3. The antenna device for tracking and capturing a drone according to claim 1, characterized in that: The high-precision measurement unit is an INS / GNSS combined navigation unit consisting of an inertial navigation system and dual GPS / BD receivers; the inertial navigation system is an attitude calculation unit with three fiber optic gyroscopes and three quartz flexible accelerometers as measurement devices and a DSP as the computing core.

4. A method for capturing a drone using an antenna, characterized in that: The method is implemented by an antenna device for tracking and capturing a drone as described in any one of claims 1 to 3; specifically as follows: During the process of establishing communication between the drone and the antenna, the drone sends the real-time position information of the drone to the antenna, and also sends the drone's flight time information, to ensure that after a long period of communication failure, both parties agree to move to the same area so that communication can be established eventually; After the communication is interrupted, the drone sends a single-carrier signal at the lowest frequency in the communication band to increase the beam width and facilitate successful antenna capture; The receiver adds a "pre-lock" status report. When the antenna is aligned with the drone signal sidelobe, the receiver reports the pre-lock status to the antenna control unit, thereby informing the antenna control unit that the antenna is now pointing close to the target drone.

5. The method for capturing a drone using an antenna according to claim 4, characterized in that: There are two situations in which communication is interrupted. One is when a drone passes directly above the antenna, and communication is interrupted due to the influence of the antenna's zenith blind spot. The drone is allowed to fly straight, and the antenna is pointed to a position where the drone may be out of the blind spot in the future, waiting until the drone flies out of the antenna blind spot and communication is re-established. When the drone enters the zenith blind spot and communication is interrupted, the timing function is started. If the target drone cannot be captured within the specified time, it is considered that the target is completely lost, the antenna's blind waiting is interrupted, and the large-scale search mode is switched to; Another situation is the communication interruption that occurs when the drone does not pass directly above the antenna; After the communication is interrupted, let the UAV hover at the lost point, and the antenna search sequence should be from the center of the search map to the outside; The wide-range search mode is a working mode that starts with a certain elevation angle and conducts a wide-range search of the airspace in a specific gradient decreasing manner. For each pitch angle, the azimuth performs a 360° rapid circular motion. If the target drone is not found, the pitch angle is reduced by a certain amount to make the azimuth perform a 360° rapid circular motion again; if the target drone is found, the pitch angle is fixed, and the azimuth axis performs a precise search within 5° left and right of the azimuth geographic pointing, until the receiver reports a status change from "pre-lock" to "lock", thereby achieving accurate capture of the target drone.

6. The method for capturing a drone using an antenna according to claim 5, characterized in that: The specific gradient is the half-power beam width times.

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