Ground station system for remote identification of unmanned aerial vehicle

Abstract

The invention discloses a ground station system for remote identification of an unmanned aerial vehicle, and relates to the technical field of airspace unmanned aerial vehicle monitoring, and the ground station system comprises a signal processing unit and an unmanned aerial vehicle positioning module: the signal processing unit is composed of a signal screening module, a demodulator module and a message assembly module; the signal screening module is used for screening the unmanned aerial vehicle remote identification signal of the target unmanned aerial vehicle to obtain a prepared unmanned aerial vehicle identification signal of the target unmanned aerial vehicle; the demodulator module is used for demodulating a prepared unmanned aerial vehicle identification signal of the target unmanned aerial vehicle to obtain remote identification information of the target unmanned aerial vehicle; the message assembly module is used for performing message assembly on the remote identification information of the target unmanned aerial vehicle to obtain a first message of the target unmanned aerial vehicle; the unmanned aerial vehicle positioning module is used for positioning the target unmanned aerial vehicle to obtain motion information of the target unmanned aerial vehicle, accurate positioning of the target unmanned aerial vehicle is realized, and the problem of inaccurate coordinate positioning of the target unmanned aerial vehicle is solved.

Description

Technical Field

[0001] The invention belongs to the technical field of airspace unmanned aerial vehicle monitoring, and in particular is a ground station system for remote identification of unmanned aerial vehicles. Background Art

[0002] In recent years, the global civil unmanned aerial vehicle (commonly known as civil drone) industry has developed rapidly. Due to its easy, fast and flexible operation, it is widely used in agriculture, forestry, electricity, meteorology, ocean monitoring, remote sensing mapping, logistics, emergency rescue and other fields. However, due to its easy modification and difficulty in prevention, it is easy to appear "illegal flying" and "random flying", which has a certain impact on public safety. Therefore, the demand for monitoring and controlling drones, maintaining air order, and ensuring real-time safety of low-altitude airspace is growing.

[0003] At present, the main methods for locating target drones are active radar positioning, sound-based positioning, and optical recognition tracking. When locating drones, traditional methods have problems such as inaccurate drone coordinate positioning and drone recognition errors; To this end, the present invention proposes a ground station system for remote identification of unmanned aerial vehicles. Summary of the invention

[0004] The purpose of the present invention is to propose a ground station system for remote identification of unmanned aerial vehicles to solve the problems raised in the above background technology.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions: A ground station system for remote identification of unmanned aerial vehicles, including a signal processing unit, a unmanned aerial vehicle positioning module and a cloud server: The signal processing unit is used to process the drone remote identification signal sent by the target drone; the signal processing unit is composed of a signal receiving antenna, a signal receiver, a signal screening module, a demodulator module and a message assembly module; The signal receiving antenna and the signal receiver are used together to collect the drone remote identification signal sent by the target drone and send it to the signal screening module; The signal screening module is used to screen the drone remote identification signal of the target drone, obtain the preliminary drone identification signal of the target drone and send it to the demodulator module; The demodulator module is used to demodulate the preliminary UAV identification signal of the target UAV, demodulate to obtain the remote identification information of the target UAV and send it to the message assembly module; The message assembly module is used to assemble the remote identification information of the target UAV into a message, assemble to obtain a first message of the target UAV and send it to the UAV positioning module; The drone positioning module is used to locate the target drone, obtain the motion information of the target drone and upload it to the cloud server; the cloud server is used to store the motion information of multiple target drones, and the user judges the overall motion state of the target drones in the current airspace based on the motion states of the multiple target drones.

[0006] Furthermore, there are three groups of signal receiving antennas and signal receivers, which are used to receive the wireless LAN automatic broadcast identification signal, Bluetooth automatic broadcast identification signal and ADS-B signal corresponding to medium and large drones sent by the target drone, and record the received signal as the drone remote identification signal.

[0007] Furthermore, the screening process of the signal screening module is specifically as follows: Obtain the standard signal wave peak value, standard signal wave trough value, standard signal frequency and standard signal period of the standard signal sent by the target UAV; The UAV remote identification signal of the target UAV is compared with the peak value of the standard signal and the trough value of the standard signal respectively; If the maximum peak value of the target drone's remote identification signal is greater than the peak value of the standard signal or the minimum trough value of the target drone's remote identification signal is greater than or equal to the trough value of the standard signal, the corresponding drone remote identification signal is deemed to be discarded; If the maximum peak value of the target UAV's UAV remote identification signal is less than or equal to the standard signal peak value, and the minimum trough value of the target UAV's UAV remote identification signal is greater than or equal to the standard signal trough value; the corresponding UAV remote identification signal will be retained.

[0008] Furthermore, the screening process of the signal screening module also includes: The frequency of the retained UAV remote identification signal is counted and recorded as the comparison signal frequency, and the period of the retained UAV remote identification signal is counted and recorded as the comparison signal period; Match the comparison signal frequency with the standard signal frequency, and match the comparison signal period with the standard signal period; if the comparison signal frequency is different from the standard signal frequency, or the comparison signal period is different from the standard signal period, the corresponding UAV remote identification signal is discarded; If the comparison signal frequency is the same as the standard signal frequency, and the comparison signal period is the same as the standard signal period, the corresponding UAV remote identification signal is recorded as the preliminary UAV identification signal.

[0009] Furthermore, the demodulation process of the demodulator module is specifically as follows: Identify the signal type of the identification signal of the prepared UAV, which can be an amplitude modulation signal, a double sideband signal, a single sideband signal or a frequency modulation signal; If it is an amplitude modulated signal, the prepared UAV identification signal is demodulated by a type of demodulation algorithm; Among them, one type of demodulation algorithm is as follows: Get the signal expression XH(n) of the identification signal of the prepared UAV; XH(n)=a(n)×cos(ω(n)+φ), where a(n)=A0+m(n); a(n) is the modulated envelope signal, n represents the index over time, XH(n) is used to describe the instantaneous value of the drone identification signal on the time axis, cos is the cosine function, ω(n) represents the angular frequency, φ represents the initial phase, A0 represents the DC component, and m(n) is the modulation signal; Perform orthogonal decomposition on the signal expression XH(n) to obtain the in-phase component TX(n) and the orthogonal component ZJ(n); TX(n)=a(n)×cosφ; ZJ(n)=a(n)×sinφ; The square root of the sum of the squares of the orthogonal components and the in-phase components is taken, and then the DC component A0 is subtracted to obtain the modulated signal m(n), so as to demodulate the prepared UAV identification signal and obtain the remote identification information of the target UAV, wherein the remote identification information includes the UAV identification information, timestamp and status flag of the target UAV.

[0010] Furthermore, the demodulation process of the demodulator module further includes: If it is a double-sideband signal, the prepared UAV identification signal is demodulated using a second-class demodulation algorithm; Among them, the two types of demodulation algorithms are as follows: Get the signal expression XH(n) of the identification signal of the prepared UAV; XH(n)=m(n)×cosω(n); Perform orthogonal decomposition on the signal expression XH(n) to obtain the in-phase component TX(n) and the orthogonal component ZJ(n); TX(n)=m(n); ZJ(n)=0; The in-phase component is the modulation signal m(n), which is used to demodulate the identification signal of the prepared UAV and obtain the remote identification information of the target UAV. If it is a single-sideband signal, the prepared drone identification signal is demodulated using three types of demodulation algorithms; Among them, the three types of demodulation algorithms are as follows: Get the signal expression XH(n) of the identification signal of the prepared UAV; XH(n)=m(n)×cosω(n)±m1(n)×sinω(n); where - represents the upper sideband, + represents the lower sideband, and m1(n) is the Hilbert transform of m(n); Perform orthogonal decomposition on the signal expression XH(n) to obtain the in-phase component TX(n) and the orthogonal component ZJ(n); TX(n)=m(n); ZJ(n)=±m1(n); The in-phase component is the modulation signal m(n), which is used to demodulate the identification signal of the prepared UAV and obtain the remote identification information of the target UAV.

[0011] Furthermore, the demodulation process of the demodulator module further includes: If it is a frequency modulated signal, the prepared drone identification signal is demodulated using four types of demodulation algorithms; Among them, the four types of demodulation algorithms are as follows: Get the signal expression XH(n) of the identification signal of the prepared UAV; ; k is a constant; Perform orthogonal decomposition on the signal expression XH(n) to obtain the in-phase component TX(n) and the orthogonal component ZJ(n); ; ; The calculation function JS(n) is obtained by performing an inverse tangent operation on the ratio of the orthogonal component to the isotropic component: ; Differentiate the calculated function to obtain the modulated signal: JS(n)-JS(n-1)=m(n); The identification signal of the prepared UAV is demodulated to obtain the remote identification information of the target UAV.

[0012] Furthermore, the assembly process of the message assembly module is specifically as follows: Obtain the remote identification information corresponding to the target UAV and obtain the sending time of the identification signal of the standby UAV; Read the current time, and obtain the transmission duration of the prepared drone identification signal by subtracting the sending time from the current time; Read the transmission speed of the identification signal of the prepared UAV, and determine the position coordinates of the target UAV at the time of transmission by multiplying the transmission time by the transmission speed, which are recorded as the first UAV coordinates; The protocol type of the serial port output data format connected to the message assembly module is obtained, and the remote identification information corresponding to the target UAV and the coordinates of the first UAV are encapsulated into a first message according to the protocol type; and the message header, message payload and check code of the first message are set.

[0013] Further, after receiving the first message from the target drone, the drone positioning module sends a positioning signal to the target drone and records a first sending time T1 of sending the positioning signal; After receiving the positioning signal, the target UAV generates a feedback signal and sends the feedback signal and the UAV remote signal of the target UAV to the signal receiver. The feedback signal and the UAV remote signal of the target UAV pass through the signal screening module, the demodulator module and the message combination module in turn to obtain the second message of the target UAV.

[0014] Furthermore, the positioning process of the drone positioning module is as follows: Obtain a first message corresponding to the target UAV, identify the first message and obtain the first UAV coordinates (X1, Y1, Z1) of the target UAV; The UAV positioning module receives the second message, identifies the second message and obtains the second UAV coordinates (X2, Y2, Z2) of the target UAV; and records the receiving time of the second message as the second receiving time T2; The real-time running speed SYS of the target UAV at time T2 is calculated by the formula, and the specific formula is as follows:

[0015] The offset angle XPY of the target drone around the X axis at time T2, that is, the rolling angle, is calculated using the formula as follows: ; Among them, the roll angle is used to describe the degree of left-right tilt of the target drone; The angle YPY of the target drone's displacement around the Y axis at time T2, i.e. the pitch angle, is calculated using the formula as follows: ; Among them, the pitch angle is used to describe the degree to which the target drone tilts forward and backward; The angle ZPY of the target drone's displacement around the Z axis at time T2, i.e. the yaw angle, is calculated using the formula as follows: ; Among them, the yaw angle is used to describe the actual heading of the target drone; The real-time running speed, roll angle, pitch angle and yaw angle at time T2 are summarized to obtain the motion information of the target UAV.

[0016] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are: 1. The present invention first collects the UAV remote identification signal sent by the target UAV through a signal receiver, and then uses a signal screening module to screen the UAV remote identification signal of the target UAV to obtain a preliminary UAV identification signal of the target UAV, and then uses a demodulator module to demodulate the preliminary UAV identification signal of the target UAV to obtain the remote identification information of the target UAV; the present invention realizes the analysis of the UAV remote identification signal corresponding to the target UAV.

[0017] 2. The present invention utilizes a message assembly module to perform message assembly on the remote identification information of the target UAV, obtains a first message and a second message of the target UAV, and finally utilizes a UAV positioning module to locate the target UAV through the first message and the second message, and obtains the motion information of the target UAV; the present invention realizes the recognition of the motion state of the target UAV, and then realizes the precise positioning of the target UAV. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to facilitate understanding by those skilled in the art, the present invention is further described below with reference to the accompanying drawings.

[0019] Figure 1 It is the overall system block diagram of the present invention.

[0020] Figure 2 It is a schematic diagram of the framework of the signal processing unit in the invention.

[0021] Figure 3 The present invention is a schematic diagram of the process of the method. DETAILED DESCRIPTION

[0022] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than 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.

[0023] Example 1, please refer to Figure 1 and Figure 2 As shown, the technical solution provided by the present invention is: a ground station system for remote identification of unmanned aerial vehicles, including a signal processing unit, a unmanned aerial vehicle positioning module and a cloud server; like Figure 3 As shown, the signal processing unit is used to process the drone remote identification signal sent by the target drone; the signal processing unit is composed of a signal receiving antenna, a signal receiver, a signal screening module, a demodulator module and a message assembly module; In this embodiment, the signal receiving antenna and the signal receiver are used together to collect the drone remote identification signal sent by the target drone and send it to the signal screening module; wherein, there are three groups of signal receiving antennas and signal receivers, which are used to receive the wireless LAN automatic broadcast identification signal, Bluetooth automatic broadcast identification signal and ADS-B signal corresponding to medium and large drones sent by the target drone, and record the received signal as the drone remote identification signal.

[0024] In this embodiment, the signal screening module is used to screen the drone remote identification signal of the target drone to obtain the preliminary drone identification signal. The screening process is as follows: Obtain the standard signal peak value, standard signal trough value, standard signal frequency and standard signal period of the standard signal sent by the target UAV; wherein the standard signal peak value is the maximum offset of the target UAV corresponding to the UAV remote identification signal in the positive direction, the standard signal trough value is the maximum offset of the target UAV corresponding to the UAV remote identification signal in the negative direction, the standard signal frequency refers to the number of times the standard signal is repeated per unit time, the standard signal period refers to the time required for the standard signal to repeat once, and the standard signal frequency and the standard signal period are reciprocal of each other; The UAV remote identification signal of the target UAV is compared with the peak value of the standard signal and the trough value of the standard signal respectively; If the maximum peak value of the target drone's remote identification signal is greater than the peak value of the standard signal or the minimum trough value of the target drone's remote identification signal is greater than or equal to the trough value of the standard signal, the corresponding drone remote identification signal is deemed to be discarded; If the maximum peak value of the target drone's remote identification signal is less than or equal to the standard signal peak value, and the minimum trough value of the target drone's remote identification signal is greater than or equal to the standard signal trough value; then the corresponding drone remote identification signal is retained; The frequency of the retained UAV remote identification signal is counted and recorded as the comparison signal frequency, and the period of the retained UAV remote identification signal is counted and recorded as the comparison signal period; Match the comparison signal frequency with the standard signal frequency, and match the comparison signal period with the standard signal period; if the comparison signal frequency is different from the standard signal frequency, or the comparison signal period is different from the standard signal period, the corresponding UAV remote identification signal is discarded; if the comparison signal frequency is the same as the standard signal frequency, and the comparison signal period is the same as the standard signal period, the corresponding UAV remote identification signal is recorded as a preliminary UAV identification signal; The signal screening module sends the preliminary UAV identification signal of the target UAV to the demodulator module.

[0025] Specifically, the demodulator module is used to demodulate the preliminary drone identification signal of the target drone, and the demodulation process is as follows: Identify the signal type of the identification signal of the prepared UAV, which can be an amplitude modulation signal, a double sideband signal, a single sideband signal or a frequency modulation signal; If it is an amplitude modulated signal, the prepared UAV identification signal is demodulated by a type of demodulation algorithm; Among them, one type of demodulation algorithm is as follows: Get the signal expression XH(n) of the identification signal of the prepared UAV; XH(n)=a(n)×cos(ω(n)+φ), where a(n)=A0+m(n); a(n) is the modulated envelope signal, n represents the index over time, XH(n) is used to describe the instantaneous value of the drone identification signal on the time axis, cos is the cosine function, ω(n) represents the angular frequency, φ represents the initial phase, A0 represents the DC component, and m(n) is the modulation signal; Perform orthogonal decomposition on the signal expression XH(n) to obtain the in-phase component TX(n) and the orthogonal component ZJ(n); TX(n)=a(n)×cosφ; ZJ(n)=a(n)×sinφ; The square root of the sum of the squares of the orthogonal component and the in-phase component is taken, and then the DC component A0 is subtracted to obtain the modulated signal m(n), so as to demodulate the identification signal of the prepared UAV and obtain the remote identification information of the target UAV, wherein the remote identification information includes the UAV identification information, timestamp and status flag of the target UAV; UAV identification information such as ID (such as FAA registration code), model, manufacturer, etc.; status indicators such as flight mode (manual / automatic), battery level, fault code; If it is a double-sideband signal, the prepared UAV identification signal is demodulated using a second-class demodulation algorithm; Among them, the two types of demodulation algorithms are as follows: Get the signal expression XH(n) of the identification signal of the prepared UAV; XH(n)=m(n)×cosω(n); Perform orthogonal decomposition on the signal expression XH(n) to obtain the in-phase component TX(n) and the orthogonal component ZJ(n); TX(n)=m(n); ZJ(n)=0; The in-phase component is the modulation signal m(n), which is used to demodulate the identification signal of the prepared UAV and obtain the remote identification information of the target UAV. If it is a single-sideband signal, the prepared drone identification signal is demodulated using three types of demodulation algorithms; Among them, the three types of demodulation algorithms are as follows: Get the signal expression XH(n) of the identification signal of the prepared UAV; XH(n)=m(n)×cosω(n)±m1(n)×sinω(n); where - represents the upper sideband, + represents the lower sideband, and m1(n) is the Hilbert transform of m(n); Perform orthogonal decomposition on the signal expression XH(n) to obtain the in-phase component TX(n) and the orthogonal component ZJ(n); TX(n)=m(n); ZJ(n)=±m1(n); The in-phase component is the modulation signal m(n), which is used to demodulate the identification signal of the prepared UAV and obtain the remote identification information of the target UAV. If it is a frequency modulated signal, the prepared drone identification signal is demodulated using four types of demodulation algorithms; Among them, the four types of demodulation algorithms are as follows: Get the signal expression XH(n) of the identification signal of the prepared UAV; ; k is a constant; Perform orthogonal decomposition on the signal expression XH(n) to obtain the in-phase component TX(n) and the orthogonal component ZJ(n); ; ; The calculation function JS(n) is obtained by performing an inverse tangent operation on the ratio of the orthogonal component to the isotropic component: ; Differentiate the calculated function to obtain the modulated signal: JS(n)-JS(n-1)=m(n); Demodulate the identification signal of the prepared UAV to obtain the remote identification information of the target UAV; The demodulator module sends the remote identification information corresponding to the target drone to the message assembly module.

[0026] In the specific implementation, the message assembly module is used to assemble the remote identification information of the target drone. The message assembly process is as follows: Obtain the remote identification information corresponding to the target UAV and obtain the sending time of the identification signal of the standby UAV; Read the current time, and obtain the transmission duration of the prepared drone identification signal by subtracting the sending time from the current time; Read the transmission speed of the identification signal of the prepared UAV, and determine the position coordinates of the target UAV at the time of transmission by multiplying the transmission time by the transmission speed, which are recorded as the first UAV coordinates; Obtaining a protocol type of a serial port output data format connected to the message assembly module, and encapsulating the remote identification information corresponding to the target UAV and the coordinates of the first UAV into a first message according to the protocol type; Set the message header, message payload and checksum of the first message; the message header is the starting part of the message, and the content of the message header includes the source address, destination address, message type, message length, protocol version, service type and time to live (TTL); the message payload is the actual data part of the message, which carries the information to be transmitted; the checksum is used to detect whether an error occurs during the transmission of the message; The message assembly module sends the first message of the target UAV to the UAV positioning module.

[0027] Further, after receiving the first message from the target drone, the drone positioning module sends a positioning signal to the target drone and records a first sending time T1 of sending the positioning signal; After receiving the positioning signal, the target UAV generates a feedback signal, and sends the feedback signal and the UAV remote signal of the target UAV to the signal receiver. The feedback signal and the UAV remote signal of the target UAV pass through the signal screening module, the demodulator module and the message combination module in turn to obtain the second message of the target UAV; Specifically, the drone positioning module is used to locate the target drone. The message assembly module is connected to the drone positioning module through a serial port. The process of locating the target drone is as follows: Obtain a first message corresponding to the target UAV, identify the first message and obtain the first UAV coordinates (X1, Y1, Z1) of the target UAV; The UAV positioning module receives the second message, identifies the second message and obtains the second UAV coordinates (X2, Y2, Z2) of the target UAV; and records the receiving time of the second message as the second receiving time T2; The real-time running speed SYS of the target UAV at time T2 is calculated by the formula, and the specific formula is as follows:

[0028] The offset angle XPY of the target drone around the X axis at time T2, that is, the rolling angle, is calculated using the formula as follows: ; Among them, the roll angle is used to describe the degree of left-right tilt of the target drone; The angle YPY of the target drone's displacement around the Y axis at time T2, i.e. the pitch angle, is calculated using the formula as follows: ; Among them, the pitch angle is used to describe the degree to which the target drone tilts forward and backward; The angle ZPY of the target drone's displacement around the Z axis at time T2, i.e. the yaw angle, is calculated using the formula as follows: ; Among them, the yaw angle is used to describe the actual heading of the target drone; The real-time running speed, roll angle, pitch angle and yaw angle at time T2 are summarized to obtain the motion information of the target UAV; The drone positioning module uploads the motion state of the target drone at the second receiving moment to the cloud server through the Internet interface; specifically, the upload is performed through network protocols such as TCP, UDP, MQTT, or through 4G LTE wireless; The cloud server is used to store the motion information of multiple target drones. Users can judge the overall motion status of the target drones in the current airspace based on the motion status of multiple target drones.

[0029] In this application, if corresponding calculation formulas appear, the above calculation formulas are all dimensionless and take their numerical calculations. The weight coefficients, proportional coefficients and other coefficients in the formulas are set to a result value obtained by quantifying each parameter. The size of the weight coefficient and the proportional coefficient can be determined as long as it does not affect the proportional relationship between the parameter and the result value.

[0030] Embodiment 2, as Figure 3 As shown, based on another concept of the same invention, a ground station method for remote identification of drones is now proposed, comprising the following steps: Step S101, collecting the drone remote identification signal of the target drone, and screening to obtain the preliminary drone identification signal of the target drone; Step S102, demodulating the preliminary UAV identification signal of the target UAV to obtain remote identification information corresponding to the target UAV; Step S103, assembling the remote identification information of the target UAV into messages to obtain a first message of the target UAV, and similarly obtaining a second message; Step 104, positioning the target UAV according to the first message and the second message, obtaining the motion information of the target UAV and uploading it to the cloud server; Step S105, the cloud server is used to store the motion information of multiple target drones, and the user determines the overall motion state of the target drones in the current airspace based on the motion states of the multiple target drones.

[0031] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to only specific implementation methods. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A ground station system for remote identification of unmanned aerial vehicles, comprising a signal processing unit, an unmanned aerial vehicle positioning module and a cloud server, characterized in that: The signal processing unit is used to process the drone remote identification signal sent by the target drone; the signal processing unit is composed of a signal receiving antenna, a signal receiver, a signal screening module, a demodulator module and a message assembly module; the signal receiving antenna and the signal receiver are used together to collect the drone remote identification signal sent by the target drone and send it to the signal screening module; the signal screening module is used to screen the drone remote identification signal of the target drone, obtain the preliminary drone identification signal of the target drone and send it to the demodulator module; The demodulator module is used to demodulate the preliminary drone identification signal of the target drone, demodulate to obtain the remote identification information of the target drone and send it to the message assembly module; the message assembly module is used to assemble the remote identification information of the target drone, assemble to obtain the first message of the target drone and send it to the drone positioning module; the drone positioning module is used to locate the target drone, obtain the motion information of the target drone and upload it to the cloud server; the cloud server is used to store the motion information of multiple target drones, and the user judges the overall motion state of the target drones in the current airspace based on the motion state of the multiple target drones.

2. A ground station system for remote identification of unmanned aerial vehicles according to claim 1, characterized in that: There are three groups of signal receiving antennas and signal receivers, which are used to receive wireless LAN automatic broadcast identification signals, Bluetooth automatic broadcast identification signals and ADS-B signals corresponding to medium and large drones sent by the target drone, and record the received signals as drone remote identification signals.

3. A ground station system for remote identification of unmanned aerial vehicles according to claim 1, characterized in that: The screening process of the signal screening module is as follows: Obtain the standard signal wave peak value, standard signal wave trough value, standard signal frequency and standard signal period of the standard signal sent by the target UAV; The UAV remote identification signal of the target UAV is compared with the peak value of the standard signal and the trough value of the standard signal respectively; If the maximum peak value of the target drone's remote identification signal is greater than the peak value of the standard signal or the minimum trough value of the target drone's remote identification signal is greater than or equal to the trough value of the standard signal, the corresponding drone remote identification signal is deemed to be discarded; If the maximum peak value of the target UAV's UAV remote identification signal is less than or equal to the standard signal peak value, and the minimum trough value of the target UAV's UAV remote identification signal is greater than or equal to the standard signal trough value; the corresponding UAV remote identification signal will be retained.

4. A ground station system for remote identification of unmanned aerial vehicles according to claim 3, characterized in that: The screening process of the signal screening module also includes: The frequency of the retained UAV remote identification signal is counted and recorded as the comparison signal frequency, and the period of the retained UAV remote identification signal is counted and recorded as the comparison signal period; Match the comparison signal frequency with the standard signal frequency, and match the comparison signal period with the standard signal period; if the comparison signal frequency is different from the standard signal frequency, or the comparison signal period is different from the standard signal period, the corresponding UAV remote identification signal is discarded; If the comparison signal frequency is the same as the standard signal frequency, and the comparison signal period is the same as the standard signal period, the corresponding UAV remote identification signal is recorded as the preliminary UAV identification signal.

5. A ground station system for remote identification of unmanned aerial vehicles according to claim 1, characterized in that: The demodulation process of the demodulator module is as follows: Identify the signal type of the identification signal of the prepared UAV, which can be an amplitude modulation signal, a double sideband signal, a single sideband signal or a frequency modulation signal; If it is an amplitude modulated signal, the prepared UAV identification signal is demodulated by a type of demodulation algorithm; Among them, one type of demodulation algorithm is as follows: Get the signal expression XH(n) of the identification signal of the prepared UAV; XH(n)=a(n)×cos(ω(n)+φ), where a(n)=A0+m(n); a(n) is the modulated envelope signal, n represents the index over time, XH(n) is used to describe the instantaneous value of the drone identification signal on the time axis, cos is the cosine function, ω(n) represents the angular frequency, φ represents the initial phase, A0 represents the DC component, and m(n) is the modulation signal; Perform orthogonal decomposition on the signal expression XH(n) to obtain the in-phase component TX(n) and the orthogonal component ZJ(n); TX(n)=a(n)×cosφ; ZJ(n)=a(n)×sinφ; The square root of the sum of the squares of the orthogonal components and the in-phase components is taken, and then the DC component A0 is subtracted to obtain the modulated signal m(n), so as to demodulate the prepared UAV identification signal and obtain the remote identification information of the target UAV, wherein the remote identification information includes the UAV identification information, timestamp and status flag of the target UAV.

6. A ground station system for remote identification of unmanned aerial vehicles according to claim 5, characterized in that: The demodulation process of the demodulator module also includes: If it is a double-sideband signal, the prepared UAV identification signal is demodulated using a second-class demodulation algorithm; Among them, the two types of demodulation algorithms are as follows: Get the signal expression XH(n) of the identification signal of the prepared UAV; XH(n)=m(n)×cosω(n); Perform orthogonal decomposition on the signal expression XH(n) to obtain the in-phase component TX(n) and the orthogonal component ZJ(n); TX(n)=m(n); ZJ(n)=0; The in-phase component is the modulation signal m(n), which is used to demodulate the identification signal of the prepared UAV and obtain the remote identification information of the target UAV. If it is a single-sideband signal, the prepared drone identification signal is demodulated using three types of demodulation algorithms; Among them, the three types of demodulation algorithms are as follows: Get the signal expression XH(n) of the identification signal of the prepared UAV; XH(n)=m(n)×cosω(n)±m1(n)×sinω(n); where - represents the upper sideband, + represents the lower sideband, and m1(n) is the Hilbert transform of m(n); Perform orthogonal decomposition on the signal expression XH(n) to obtain the in-phase component TX(n) and the orthogonal component ZJ(n); TX(n)=m(n); ZJ(n)=±m1(n); The in-phase component is the modulation signal m(n), which is used to demodulate the identification signal of the prepared UAV and obtain the remote identification information of the target UAV.

7. A ground station system for remote identification of unmanned aerial vehicles according to claim 6, characterized in that: The demodulation process of the demodulator module also includes: If it is a frequency modulated signal, the prepared drone identification signal is demodulated using four types of demodulation algorithms; Among them, the four types of demodulation algorithms are as follows: Get the signal expression XH(n) of the identification signal of the prepared UAV; ; k is a constant; Perform orthogonal decomposition on the signal expression XH(n) to obtain the in-phase component TX(n) and the orthogonal component ZJ(n); ； ； The calculation function JS(n) is obtained by performing an inverse tangent operation on the ratio of the orthogonal component to the isotropic component: ； Differentiate the calculated function to obtain the modulated signal: JS(n)-JS(n-1)=m(n); The identification signal of the prepared UAV is demodulated to obtain the remote identification information of the target UAV.

8. A ground station system for remote identification of unmanned aerial vehicles according to claim 1, characterized in that: The assembly process of the message assembly module is as follows: Obtain the remote identification information corresponding to the target UAV and obtain the sending time of the identification signal of the standby UAV; Read the current time, and obtain the transmission duration of the prepared drone identification signal by subtracting the sending time from the current time; Read the transmission speed of the identification signal of the prepared UAV, and determine the position coordinates of the target UAV at the time of transmission by multiplying the transmission time by the transmission speed, which are recorded as the first UAV coordinates; Obtaining a protocol type of a serial port output data format connected to the message assembly module, and encapsulating the remote identification information corresponding to the target UAV and the coordinates of the first UAV into a first message according to the protocol type; Set the message header, message payload, and checksum of the first message.

9. A ground station system for remote identification of unmanned aerial vehicles according to claim 8, characterized in that: After receiving the first message from the target UAV, the UAV positioning module sends a positioning signal to the target UAV and records the first sending time T1 of the positioning signal; After receiving the positioning signal, the target UAV generates a feedback signal and sends the feedback signal and the UAV remote signal of the target UAV to the signal receiver. The feedback signal and the UAV remote signal of the target UAV pass through the signal screening module, the demodulator module and the message combination module in turn to obtain the second message of the target UAV.

10. A ground station system for remote identification of unmanned aerial vehicles according to claim 1, characterized in that: The positioning process of the UAV positioning module is as follows: Obtain a first message corresponding to the target UAV, identify the first message and obtain the first UAV coordinates (X1, Y1, Z1) of the target UAV; The UAV positioning module receives the second message, identifies the second message and obtains the second UAV coordinates (X2, Y2, Z2) of the target UAV; and records the receiving time of the second message as the second receiving time T2; The real-time running speed SYS of the target UAV at time T2 is calculated by the formula, and the specific formula is as follows: ； The offset angle XPY of the target drone around the X axis at time T2, that is, the rolling angle, is calculated using the formula as follows: ; Among them, the roll angle is used to describe the degree of left-right tilt of the target drone; The angle YPY of the target drone's displacement around the Y axis at time T2, i.e. the pitch angle, is calculated using the formula as follows: ; Among them, the pitch angle is used to describe the degree to which the target drone tilts forward and backward; The angle ZPY of the target drone's displacement around the Z axis at time T2, i.e. the yaw angle, is calculated using the formula as follows: ; Among them, the yaw angle is used to describe the actual heading of the target drone; The real-time running speed, roll angle, pitch angle and yaw angle at time T2 are summarized to obtain the motion information of the target UAV.

Images