A device and method for synchronizing multi-source data of ground-to-space frequency-domain electromagnetic ground-penetrating system

Abstract

The present invention belongs to the technical field of ground-to-space frequency domain electromagnetic detection. It is a device and method for calibrating multi-source data synchronously in a ground-to-space frequency domain electromagnetic ground detection system, including an electromagnetic receiving system, which is hoisted in the air by a drone and used to obtain multi-source data in the air; a ground laser transmitter, which is used to transmit laser pulses to the electromagnetic receiving system; a ground laser receiving device, which is used to receive the laser signal reflected back by the electromagnetic receiving system; a synchronous electromagnetic emission control system, which records the timestamp of the ground laser receiving device receiving the laser signal and the ground longitude and latitude coordinates, and triggers the electromagnetic emission device to emit electromagnetic wave signals according to the signal of the ground laser receiving device; a computer, which calibrates the electromagnetic receiving system's aerial received data according to the timestamp and the ground longitude and latitude coordinates. This is aimed at the time and space asynchronization problem existing in the current ground-to-space electromagnetic detection system. It ensures the consistency of data collected from different sources in time and space.

Description

Technical Field

[0001] The present invention belongs to the technical field of ground-to-space frequency domain electromagnetic detection, and specifically relates to a device and method for synchronously calibrating multi-source data of a ground-to-space frequency domain electromagnetic ground detection system. Background Art

[0002] Ground-to-air frequency domain electromagnetic detection technology is an important geological exploration technology. It uses an electromagnetic receiving system mounted on a drone to collect data in the air. This technology can effectively detect geological structures over a large area, and is particularly suitable for areas with complex terrain or difficult to access. However, due to the instability of the flight environment (such as wind direction, flight turbulence, etc.), data synchronization problems are often encountered in ground-to-air electromagnetic detection. These problems are mainly manifested in the time asynchrony between electromagnetic data and attitude data, which in turn affects the accuracy and reliability of data processing.

[0003] At present, traditional ground-to-air frequency domain electromagnetic detection systems mainly rely on GPS time-stamping technology to synchronize air and ground data collection. Although this method is effective in some cases, the delay and instability of GPS signals, internal circuit time delays, etc., especially in remote or shielded areas, still lead to synchronization errors. In addition, the limitations of GPS devices themselves, such as signal loss and multipath effects, often exacerbate the problem of data inconsistency.

[0004] To address these synchronization issues, researchers and engineers are developing more advanced synchronization techniques. This includes using higher-precision clock systems, such as atomic clocks, to improve the accuracy of time stamping. At the same time, more complex signal processing algorithms, such as phase-based synchronization methods, are also being explored, which can directly extract time information from the received electromagnetic signals, thereby reducing dependence on external time sources. In addition, new synchronization technologies also attempt to improve the overall stability of the system and the reliability of data by integrating multiple sensor data, such as accelerometers and gyroscopes, to compensate for dynamic changes in flight. This multi-sensor fusion method can provide real-time feedback on the dynamic behavior of the drone, enabling the system to adjust the synchronization strategy of data collection in real time. Traditional ground-to-air electromagnetic detection systems mostly rely on relatively simple synchronization mechanisms, which fail to fully consider the impact of flight variables on data synchronization, resulting in data quality issues in practical applications.

[0005] The existing technology only provides an airborne electromagnetic detection method, but does not consider the data time series synchronization error caused by the delay and instability of GPS signals, internal circuit time delay, etc. Summary of the invention

[0006] The technical problem to be solved by the present invention is to provide a multi-source data synchronization calibration device for a ground-to-air frequency domain electromagnetic ground detection system, which aims to solve the time and space asynchronization problems existing in the current ground-to-air electromagnetic detection system. Through the laser transmitter, laser receiving device and electromagnetic emission control system, the consistency of data collected from different sources in time and space is ensured, thereby greatly improving the accuracy and reliability of the data.

[0007] Another aspect of the present invention provides a method for synchronously calibrating multi-source data of a ground-to-space frequency-domain electromagnetic ground-penetrating system.

[0008] The present invention is achieved in this way.

[0009] In one aspect, the present invention provides a device for synchronously calibrating multi-source data of a ground-to-space frequency-domain electromagnetic ground-penetrating system, the device comprising:

[0010] The electromagnetic receiving system is hoisted in the air by a drone to obtain multi-source data in the air;

[0011] A ground-based laser transmitter for transmitting laser pulses to an electromagnetic receiving system;

[0012] A ground laser receiving device is used to receive the laser signal reflected by the electromagnetic receiving system and record the timestamp of the received laser signal;

[0013] A synchronous electromagnetic launch control system triggers the electromagnetic launch device to launch electromagnetic wave signals according to the signal of the ground laser receiving device; and records the ground longitude and latitude coordinates of the electromagnetic launch device;

[0014] The computer calibrates and calibrates the electromagnetic receiving system's air-received data based on the timestamp and the ground longitude and latitude coordinates.

[0015] Furthermore, the ground laser transmitter comprises:

[0016] An excitation source, a laser modulator, a beam controller, a laser, and an emission optical system, wherein: the excitation source provides an adjustable energy source for the laser and drives the laser, the laser modulator is used to control the beam controller, and the laser generated by the laser passes through the beam controller and the emission optical system to optimize the focusing and transmission efficiency of the laser.

[0017] Furthermore, the ground laser receiving device includes a laser receiver, a narrow bandpass filter and a signal transmission interface. The narrow bandpass filter is installed on the optical path of the laser receiver. The signal transmission interface forwards the laser signal captured by the laser receiver to the synchronous electromagnetic emission control system.

[0018] Further, the output of the ground laser receiving device is connected to the input of the microcontroller of the synchronous electromagnetic launch control system, and the synchronous electromagnetic launch control system is programmed on the microcontroller to receive the signal of the ground laser receiving device, record the receiving time and the longitude and latitude coordinates, and send a trigger signal;

[0019] Connect the output port of the microcontroller to the control terminal of the relay so as to control the opening and closing of the relay based on the signal;

[0020] The output of the relay is connected to the start control interface of the electromagnetic launch device, and the electromagnetic launch device performs electromagnetic launch synchronously.

[0021] Furthermore, the electromagnetic receiving system air-received data is calibrated according to the timestamp and the ground longitude and latitude coordinates, including:

[0022] The ground longitude and latitude coordinates are ; is the time when the current laser signal is reflected back, and Indicates the coordinate position;

[0023] The voltage signal received by the electromagnetic receiving system is recorded as ; The time when the electromagnetic receiving system starts to receive signals;

[0024] The attitude data recorded by the attitude sensor in the electromagnetic receiving system is ; Refers to the time corresponding to the posture data recorded by the posture sensor;

[0025] The latitude and longitude coordinates recorded by GPS in the electromagnetic receiving system are: , Refers to the recording time corresponding to the point in the GPS data that is closest to the coordinates of the ground laser receiving device;

[0026] Correct the original voltage signal:

[0027] Calculating time offset , It is expressed as:

[0028] ,

[0029] The voltage signal corrected according to the time offset is: ,

[0030] is the corrected voltage signal time series, represents the voltage signal after correction;

[0031] Correcting GPS data:

[0032] According to the ground longitude and latitude coordinates , a set of coordinate points in the GPS data is obtained by the distance calculation formula The closest point , the distance calculation formula is expressed as:

[0033] ,

[0034] In the formula, =0 or Minimum, remember , calculate the time offset:

[0035] ,

[0036] Use time offset , correct the GPS data, expressed as:

[0037] ,

[0038] The time corresponding to the corrected GPS data;

[0039] Correction posture data:

[0040] The posture data is converted from the body coordinate system to the earth coordinate system through the Euler angle , , It indicates that, is the roll angle, is the pitch angle, is the yaw angle, attitude rotation matrix Constructed by Euler angles, expressed as: ,

[0041] in, The matrix form of the yaw angle is: The matrix form of pitch angle is: is the matrix form of the roll angle, and The same meaning, and The same meaning, and The meaning is the same;

[0042] ,

[0043] pass Correct the electromagnetic data changes caused by the movement of the electromagnetic receiving system, expressed as:

[0044] ,

[0045] In the formula, is the static geomagnetic field at position The value at is the attitude rotation matrix The transpose of the electromagnetic receiving system at time The attitude of the moment, To convolve the attitude data with the voltage signal of the static geomagnetic field, the response function of the electromagnetic receiving system is and Convolution processing is performed to obtain the voltage signal of motion noise , the voltage of motion noise Specifically expressed as:

[0046] ,

[0047] Calculate the cross-correlation function , representing the voltage signals of two motion noises and The degree of correlation is expressed as:

[0048] ,

[0049] represents the expected value of the product of two signals, express , express ;

[0050] By time offset , the calculation of similarity is expressed as follows:

[0051] ,

[0052] Is shifted over time The cross-correlation function of the change is used to measure the change in time The similarity of the two signals is offset in time. Solve it so that Maximization means the highest correlation, and the genetic algorithm is used to calculate the time offset Search to get the optimal time offset Make the cross-correlation function reach the maximum value, expressed as:

[0053] ,

[0054] According to the optimal time offset Time series alignment of posture data, voltage of motion noise Updated as follows:

[0055] .

[0056] On the other hand, the present invention provides a calibration method for a multi-source data synchronous calibration device of a ground-to-space frequency domain electromagnetic ground detection system, comprising:

[0057] A ground-based laser transmitter is used to transmit laser pulses to an electromagnetic receiving system in the air;

[0058] A ground laser receiving device is used to receive the laser signal reflected by the electromagnetic receiving system, and a timestamp of the received laser signal is recorded;

[0059] The electromagnetic transmitting device is triggered to transmit electromagnetic wave signals according to the signal of the ground laser receiving device;

[0060] Record the ground longitude and latitude coordinates of the electromagnetic transmitting device;

[0061] The electromagnetic receiving system's air-received data is calibrated based on the timestamp and ground longitude and latitude coordinates.

[0062] Furthermore, the electromagnetic receiving system air-received data is calibrated according to the timestamp and the ground longitude and latitude coordinates, including:

[0063] The ground longitude and latitude coordinates are ; is the time when the current laser signal is reflected back, and Indicates the coordinate position;

[0064] The voltage signal received by the electromagnetic receiving system is recorded as ; The time when the electromagnetic receiving system starts to receive signals;

[0065] The attitude data recorded by the attitude sensor in the electromagnetic receiving system is ; Refers to the time corresponding to the posture data recorded by the posture sensor;

[0066] The latitude and longitude coordinates recorded by GPS in the electromagnetic receiving system are: , Refers to the recording time corresponding to the point in the GPS data that is closest to the coordinates of the ground laser receiving device;

[0067] Correct the original voltage signal:

[0068] Calculating time offset , It is expressed as:

[0069] ,

[0070] The voltage signal corrected according to the time offset is: ,

[0071] is the corrected voltage signal time series, represents the voltage signal after correction;

[0072] Correcting GPS data:

[0073] According to the ground longitude and latitude coordinates , a set of coordinate points in the GPS data is obtained by the distance calculation formula The closest point , the distance calculation formula is expressed as:

[0074] ,

[0075] In the formula, =0 or Minimum, remember , calculate the time offset:

[0076] ,

[0077] Use time offset , correct the GPS data, expressed as:

[0078] ,

[0079] The time corresponding to the corrected GPS data;

[0080] Correction posture data:

[0081] The posture data is converted from the body coordinate system to the earth coordinate system through the Euler angle , , It indicates that, is the roll angle, is the pitch angle, is the yaw angle, attitude rotation matrix Constructed by Euler angles, expressed as: ,

[0082] in, The matrix form of the yaw angle is: The matrix form of pitch angle is: is the matrix form of the roll angle, and The same meaning, and The same meaning, and The meaning is the same;

[0083] ,

[0084] pass Correct the electromagnetic data changes caused by the movement of the electromagnetic receiving system, expressed as:

[0085] ,

[0086] In the formula, is the static geomagnetic field at position The value at is the attitude rotation matrix The transpose of the electromagnetic receiving system at time The attitude of the moment, To convolve the attitude data with the voltage signal of the static geomagnetic field, the response function of the electromagnetic receiving system is and Convolution processing is performed to obtain the voltage signal of motion noise , the voltage of motion noise Specifically expressed as:

[0087] ,

[0088] Calculate the cross-correlation function , representing the voltage signals of two motion noises and The degree of correlation is expressed as:

[0089] ,

[0090] represents the expected value of the product of two signals, express , express ;

[0091] By time offset , the calculation of similarity is expressed as follows:

[0092] ,

[0093] Is shifted over time The cross-correlation function is used to measure the change in time. The similarity of the two signals is calculated by the time offset Solve it so that Maximization means the highest correlation, and the genetic algorithm is used to calculate the time offset Search to get the optimal time offset Make the cross-correlation function reach the maximum value, expressed as:

[0094] ,

[0095] According to the optimal time offset Time series alignment of posture data, voltage of motion noise Updated as follows:

[0096] .

[0097] Compared with the prior art, the present invention has the following beneficial effects:

[0098] The present invention realizes high-precision time synchronization through the coordinated work of a ground laser transmitter and an electromagnetic receiving system, ensures the reliability and effectiveness of electromagnetic data, and improves the detection accuracy of underground structures.

[0099] The synchronization technology of the present invention ensures the alignment of attitude data with the electromagnetic signal time series, optimizes the precision of spatial data, and improves the accuracy of measurement data in complex environments.

[0100] The present invention utilizes accurate correction of GPS data to improve the accuracy of geographic positioning, support the demand for high-precision geographic information, and enhance the effects of geological exploration and environmental monitoring. BRIEF DESCRIPTION OF THE DRAWINGS

[0101] Figure 1 It is an overall block diagram of a multi-source data synchronous calibration device for a ground-to-space frequency domain electromagnetic ground detection system provided by an embodiment of the present invention;

[0102] Figure 2 It is a structural block diagram of a ground laser transmitter and a ground laser receiving device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0103] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0104] See also Figure 1 As shown, a multi-source data synchronous calibration device for a ground-to-air frequency domain electromagnetic ground-penetrating system includes an electromagnetic receiving system 1, which is hoisted in the air by a drone and is used to obtain multi-source data in the air;

[0105] A ground laser transmitter 2, used for transmitting laser pulses to the electromagnetic receiving system 1;

[0106] A ground laser receiving device 3, used to receive the laser signal reflected by the electromagnetic receiving system 1;

[0107] The synchronous electromagnetic emission control system 4 triggers the electromagnetic emission device 5 to emit electromagnetic wave signals according to the signal of the ground laser receiving device 3; records the timestamp of the ground laser receiving device 3 receiving the laser signal and the ground longitude and latitude coordinates;

[0108] The computer calibrates and demarcates the air-received data of the electromagnetic receiving system 1 according to the timestamp and the ground longitude and latitude coordinates.

[0109] The ground laser receiving device 3 and the synchronous electromagnetic emission control system 4 can interact and transmit data streams. The electromagnetic receiving system 1 carried by the UAV receives multi-source data including electromagnetic data and attitude data and performs GPS positioning.

[0110] Ground laser transmitter 2: Located below the UAV flight path, it is responsible for sending laser pulses to the UAV in the air. These pulses are received by the electromagnetic receiving system 1 on the UAV and reflected back to the ground.

[0111] The ground laser receiving device 3 receives the laser signal reflected from the UAV or the electromagnetic receiving system 1 .

[0112] See also Figure 2 As shown, the ground laser transmitter 2 includes:

[0113] An excitation source, a laser modulator, a beam controller, a laser, and an emission optical system, wherein: the excitation source provides an adjustable energy source for the laser, the laser modulator precisely controls the output of the laser through the beam controller, the laser generates laser light through the beam controller, and the emission optical system is used to optimize the focusing and transmission efficiency of the laser and to perform laser emission.

[0114] The ground laser receiving device 3 includes a laser receiver, a narrow bandpass filter and a signal transmission interface. The narrow bandpass filter is installed on the optical path of the laser receiver. The signal transmission interface forwards the laser signal captured by the laser receiver to the synchronous electromagnetic emission control system 4.

[0115] The process is as follows: the excitation source in the ground laser transmitter 2 drives the laser periodically to emit laser pulses, the laser modulator controls the direction and number of lines of the emitted laser through the beam controller, and finally the laser is emitted to the target object through the transmitting optical system; the laser receiver in the ground laser receiving device 3 receives the laser reflected back by the target object, generates a receiving signal, and finally sends the laser signal to the synchronous electromagnetic emission control system 4 through the signal transmission interface.

[0116] The synchronous electromagnetic emission control system 4 triggers the electromagnetic emission device 5 to emit electromagnetic wave signals according to the signal of the ground laser receiving device 3; records the timestamp of the ground laser receiving device 3 receiving the laser and the ground longitude and latitude coordinates;

[0117] The input end of the microcontroller of the synchronous electromagnetic emission control system 4 is connected to the output of the ground laser receiving device 3. The synchronous electromagnetic emission control system 4 is programmed on the microcontroller to receive the signal of the ground laser receiving device 3 and send a trigger signal;

[0118] Connect the output port of the microcontroller to the control terminal of the relay so as to control the opening and closing of the relay based on the signal;

[0119] The output of the relay is connected to the start control interface of the electromagnetic launch device 5, and the electromagnetic launch device 5 performs electromagnetic launch synchronously.

[0120] The working process of the synchronous electromagnetic emission control system 4 is as follows: first, the microcontroller receives the laser signal and records the current timestamp of the ground laser receiving device 3, which is the same as the timestamp of the triggering moment of the electromagnetic emission device 5, and generates a corresponding trigger signal. These signals drive the relay, which acts as a switch to control the start of the electromagnetic emission device 5. Finally, the electromagnetic emission device 5 operates according to the received trigger signal to ensure that the emitted electromagnetic wave is completely synchronized with the received laser signal time.

[0121] The overall working process of the above-mentioned multi-source data synchronous calibration device for ground-to-air frequency domain electromagnetic ground detection system includes:

[0122] System configuration: The ground laser transmitter 2 is equipped with an excitation source, which drives the laser to emit laser pulses regularly. The laser modulator and beam controller are set to control the emission parameters of the pulses, such as the pulse frequency. and pulse width The transmitting optical system ensures the focusing of the laser and maximizes the transmission efficiency through lenses and other optical elements.

[0123] Laser emission process: The emission process is given by the formula ,in, is the amplitude of the laser, is time. This formula ensures that the laser pulses have the right energy and shape to travel long distances.

[0124] Signal reception and processing: The electromagnetic receiving system 1 carried by the drone captures the laser pulse from the ground laser transmitter 2 and reflects the laser pulse. The reflected signal is received by the ground laser receiving device 3 on the ground, and the received signal is processed by the analog to digital converter and converted into a digital signal for further analysis.

[0125] Record the timestamp of the ground laser receiving device 3 receiving the laser signal. Once the laser signal is captured and the time is recorded, it will immediately send a signal to the synchronous electromagnetic launch control system. Therefore, the timestamp is consistent with the timestamp of triggering the electromagnetic launch device.

[0126] After receiving the trigger signal from the ground laser receiving device 3, the synchronous electromagnetic emission control system 4 activates the electromagnetic emission device 5 for emission. The electromagnetic emission device 5 responds to the signal from the ground laser receiving device to ensure that the emission of electromagnetic waves is almost synchronized with the time of receiving the laser signal, thereby minimizing the time error and potential synchronization delay between systems.

[0127] The electromagnetic receiving system is calibrated and calibrated based on the timestamp and the ground longitude and latitude coordinates. This includes: defining the following data:

[0128] The ground longitude and latitude coordinates are ; is the time when the current laser signal is reflected back, and Indicates the coordinate position;

[0129] The voltage signal received by the electromagnetic receiving system is recorded as ; The time when the electromagnetic receiving system starts to receive signals;

[0130] The attitude data recorded by the attitude sensor in the electromagnetic receiving system is ; Refers to the time corresponding to the posture data recorded by the posture sensor;

[0131] The latitude and longitude coordinates recorded by GPS in the electromagnetic receiving system are: , Refers to the recording time corresponding to the point in the GPS data that is closest to the coordinates of the ground laser receiving device 3;

[0132] According to the above data, corrections are made, including:

[0133] Correct the original voltage signal:

[0134] Calculating time offset , It is expressed as:

[0135] ,

[0136] The voltage signal corrected according to the time offset is: ,

[0137] is the corrected voltage signal time series, represents the voltage signal after correction;

[0138] Correcting GPS data:

[0139] According to the ground longitude and latitude coordinates , a set of coordinate points in the GPS data is obtained by the distance calculation formula The closest point , the distance calculation formula is expressed as:

[0140] ,

[0141] In the formula, =0 or Minimum, remember , calculate the time offset:

[0142] ,

[0143] Use time offset , correct the GPS data, expressed as:

[0144] ,

[0145] The time corresponding to the corrected GPS data;

[0146] Correction posture data:

[0147] The posture data is converted from the body coordinate system to the earth coordinate system through the Euler angle , , It indicates that, is the roll angle, is the pitch angle, is the yaw angle, attitude rotation matrix Constructed by Euler angles, expressed as: ,

[0148] in, The matrix form of the yaw angle is: The matrix form of pitch angle is: is the matrix form of the roll angle, and The same meaning, and The same meaning, and The meaning is the same;

[0149] ,

[0150] pass Correct the electromagnetic data changes caused by the movement of the electromagnetic receiving system, expressed as:

[0151] ,

[0152] In the formula, is the static geomagnetic field at position The value at is the attitude rotation matrix The transpose of the electromagnetic receiving system at time The attitude of the moment, To convolve the attitude data with the voltage signal of the static geomagnetic field, the response function of the electromagnetic receiving system is and Convolution processing is performed to obtain the voltage signal of motion noise , the voltage of motion noise Specifically expressed as:

[0153] ,

[0154] Calculate the cross-correlation function , representing the voltage signals of two motion noises and The degree of correlation is expressed as:

[0155] ,

[0156] represents the expected value of the product of two signals, express , express ;

[0157] By time offset , the calculation of similarity is expressed as follows:

[0158] ,

[0159] Is shifted over time The cross-correlation function is used to measure the change in time. The similarity of the two signals is calculated by the time offset Solve it so that Maximization means the highest correlation, and the genetic algorithm is used to calculate the time offset Search to get the optimal time offset Make the cross-correlation function reach the maximum value, expressed as:

[0160] ,

[0161] According to the optimal time offset Time series alignment of posture data, voltage of motion noise Updated as follows:

[0162] .

[0163] The embodiment of the present invention also provides a method for synchronously calibrating multi-source data of a ground-to-space frequency-domain electromagnetic ground-penetrating system, comprising:

[0164] A ground-based laser transmitter is used to transmit laser pulses to an electromagnetic receiving system in the air;

[0165] A ground laser receiving device is used to receive the laser signal reflected back by the electromagnetic receiving system;

[0166] The electromagnetic transmitting device is triggered to transmit electromagnetic wave signals according to the signal of the ground laser receiving device;

[0167] Record the timestamp of the laser signal received by the ground laser receiving device and the ground longitude and latitude coordinates, and trigger the electromagnetic transmitting device to transmit the electromagnetic wave signal according to the signal of the ground laser receiving device;

[0168] The electromagnetic receiving system's air-received data is calibrated based on the timestamp and ground longitude and latitude coordinates.

[0169] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A device for synchronous calibration of multi-source data of ground-to-air frequency-domain electromagnetic ground-penetrating system, characterized in that: The device includes: The electromagnetic receiving system is hoisted in the air by a drone to obtain multi-source data in the air; A ground-based laser transmitter for transmitting laser pulses to an electromagnetic receiving system; A ground laser receiving device is used to receive the laser signal reflected by the electromagnetic receiving system; A synchronous electromagnetic emission control system records the timestamp of the laser signal received by the ground laser receiving device and the ground longitude and latitude coordinates, and triggers the electromagnetic emission device to emit electromagnetic wave signals according to the signal of the ground laser receiving device; The computer calibrates the electromagnetic receiving system's air-received data based on the timestamp and the ground longitude and latitude coordinates; include: The ground longitude and latitude coordinates are ; is the time when the current laser signal is reflected back, and Indicates the coordinate position; The voltage signal received by the electromagnetic receiving system is recorded as ; The time when the electromagnetic receiving system starts to receive signals; The attitude data recorded by the attitude sensor in the electromagnetic receiving system is ; Refers to the time corresponding to the posture data recorded by the posture sensor; The latitude and longitude coordinates recorded by GPS in the electromagnetic receiving system are: , Refers to the recording time corresponding to the point in the GPS data that is closest to the coordinates of the ground laser receiving device; Correct the original voltage signal: Calculating time offset , It is expressed as: ， The voltage signal corrected according to the time offset is: , is the corrected voltage signal time series, represents the voltage signal after correction; Correcting GPS data: According to the ground longitude and latitude coordinates , a set of coordinate points in the GPS data is obtained by the distance calculation formula The closest point , the distance calculation formula is expressed as: ， In the formula, =0 or Minimum, remember , calculate the time offset: ， Use time offset , correct the GPS data, expressed as: ， The time corresponding to the corrected GPS data; Correction posture data: The posture data is converted from the body coordinate system to the earth coordinate system through the Euler angle , , It indicates that, is the roll angle, is the pitch angle, is the yaw angle, attitude rotation matrix Constructed by Euler angles, expressed as: , in, The matrix form of the yaw angle is: The matrix form of pitch angle is: is the matrix form of the roll angle, and The same meaning, and The same meaning, and The meaning is the same; ， pass Correct the electromagnetic data changes caused by the movement of the electromagnetic receiving system, expressed as: ， In the formula, is the static geomagnetic field at position The value at is the attitude rotation matrix The transpose of the electromagnetic receiving system at time The attitude of the moment, To convolve the attitude data with the voltage signal of the static geomagnetic field, the response function of the electromagnetic receiving system is and Convolution processing is performed to obtain the voltage signal of motion noise , the voltage of motion noise Specifically expressed as: ， Calculate the cross-correlation function , representing the voltage signals of two motion noises and The degree of correlation is expressed as: ， represents the expected value of the product of two signals, express , express ; By time offset , the similarity calculation is expressed as follows: ， Is shifted over time The cross-correlation function of the change is used to measure the change in time The similarity of the two signals is offset in time. Solve it so that Maximization means the highest correlation, and the genetic algorithm is used to calculate the time offset Search to get the optimal time offset Make the cross-correlation function reach the maximum value, expressed as: ， According to the optimal time offset Time series alignment of posture data, voltage of motion noise Updated as follows: 。 2. The device for synchronously calibrating multi-source data of a ground-to-space frequency-domain electromagnetic ground-penetrating system according to claim 1 is characterized in that: The ground laser transmitter comprises: An excitation source, a laser modulator, a beam controller, a laser, and an emission optical system, wherein: the excitation source provides an adjustable energy source for the laser and drives the laser, the laser modulator is used to control the beam controller, and the laser generated by the laser passes through the beam controller and the emission optical system to optimize the focusing and transmission efficiency of the laser.

3. The device for synchronously calibrating multi-source data of a ground-to-space frequency-domain electromagnetic ground-penetrating system according to claim 1, characterized in that: The ground laser receiving device includes a laser receiver, a narrow bandpass filter and a signal transmission interface. The narrow bandpass filter is installed on the optical path of the laser receiver. The signal transmission interface forwards the laser signal captured by the laser receiver to a synchronous electromagnetic emission control system.

4. A device for synchronously calibrating multi-source data of a ground-to-space frequency-domain electromagnetic ground-penetrating system according to claim 1 or 3, characterized in that: The output of the ground laser receiving device is connected to the input of the microcontroller of the synchronous electromagnetic launch control system. The synchronous electromagnetic launch control system is programmed on the microcontroller to receive the signal of the ground laser receiving device and send a trigger signal. Connect the output port of the microcontroller to the control end of the relay, and control the opening and closing of the relay based on the signal; The output of the relay is connected to the start control interface of the electromagnetic transmitting device, and the electromagnetic transmitting device synchronously transmits electromagnetic wave signals.

5. A calibration method for a multi-source data synchronous calibration device for a ground-to-space frequency domain electromagnetic ground penetrating system according to claim 1, characterized in that: include: A ground-based laser transmitter is used to transmit laser pulses to an electromagnetic receiving system in the air; A ground laser receiving device is used to receive the laser signal reflected back by the electromagnetic receiving system; Record the timestamp of the laser signal received by the ground laser receiving device and the ground longitude and latitude coordinates, and trigger the electromagnetic transmitting device to transmit the electromagnetic wave signal according to the signal of the ground laser receiving device; Calibrate the electromagnetic receiving system's air-received data based on the timestamp and ground longitude and latitude coordinates; Calibrate the electromagnetic receiving system's airborne received data based on the timestamp and ground longitude and latitude coordinates, including: The ground longitude and latitude coordinates are ; is the time when the current laser signal is reflected back, and Indicates the coordinate position; The voltage signal received by the electromagnetic receiving system is recorded as ; The time when the electromagnetic receiving system starts to receive signals; The attitude data recorded by the attitude sensor in the electromagnetic receiving system is ; Refers to the time corresponding to the posture data recorded by the posture sensor; The latitude and longitude coordinates recorded by GPS in the electromagnetic receiving system are: , Refers to the recording time corresponding to the point in the GPS data that is closest to the coordinates of the ground laser receiving device; Correct the original voltage signal: Calculating time offset , It is expressed as: ， The voltage signal corrected according to the time offset is: , is the corrected voltage signal time series, represents the voltage signal after correction; Correcting GPS data: According to the ground longitude and latitude coordinates , a set of coordinate points in the GPS data is obtained by the distance calculation formula The closest point , the distance calculation formula is expressed as: ， In the formula, =0 or Minimum, remember , calculate the time offset: ， Use time offset , correct the GPS data, expressed as: ， The time corresponding to the corrected GPS data; Correction posture data: The posture data is converted from the body coordinate system to the earth coordinate system through the Euler angle , , It indicates that, is the roll angle, is the pitch angle, is the yaw angle, attitude rotation matrix Constructed by Euler angles, expressed as: , in, The matrix form of the yaw angle is: The matrix form of pitch angle is: is the matrix form of the roll angle, and The same meaning, and The same meaning, and The meaning is the same; ， pass Correct the electromagnetic data changes caused by the movement of the electromagnetic receiving system, expressed as: ， In the formula, is the static geomagnetic field at position The value at is the attitude rotation matrix The transpose of the electromagnetic receiving system at time The attitude of the moment, To convolve the attitude data with the voltage signal of the static geomagnetic field, the response function of the electromagnetic receiving system is and Convolution processing is performed to obtain the voltage signal of motion noise , the voltage of motion noise Specifically expressed as: ， Calculate the cross-correlation function , representing the voltage signals of two motion noises and The degree of correlation is expressed as: ， represents the expected value of the product of two signals, express , express ; By time offset , the similarity calculation is expressed as follows: ， Is shifted over time The cross-correlation function of the change is used to measure the change in time The similarity of the two signals is offset in time. Solve it so that Maximization means the highest correlation, and the genetic algorithm is used to calculate the time offset Search to get the optimal time offset Make the cross-correlation function reach the maximum value, expressed as: ， According to the optimal time offset Time series alignment of posture data, voltage of motion noise Updated as follows: 。

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