Multi-parameter MIMO airborne time-frequency electromagnetic detection system and method

Abstract

The present invention provides a multi-parameter MIMO airborne time-frequency detection system and method, which can be applied to the field of underground medium detection technology. The system includes: a flight platform, a transmitting subsystem, a receiving subsystem, and a measurement and control subsystem. The transmitting subsystem is configured to load a first current pulse into a transmitting coil via a first current transmitter to achieve primary electromagnetic field excitation, and to load a second current pulse into a compensation coil via a second current transmitter to achieve compensatory electromagnetic field excitation; the receiving subsystem is configured to sample the first and second current pulses and collect the secondary electromagnetic field response to obtain electrical property information of the underground medium in the target detection area; the measurement and control subsystem is configured to issue control instructions to the transmitting subsystem and the receiving subsystem based on the sampling results and set detection parameters, and monitor the working status of the detection system. The measurement and control subsystem adjusts the first and second current pulses in real time.

Description

Technical Field

[0001] The present invention relates to the field of underground medium detection technology, and more specifically, to a multi-parameter MIMO airborne time-frequency detection system and method based on a flying platform and electromagnetic detection technology, in order to obtain electrical information of valuable or new dielectric materials at different depths underground. Background Art

[0002] The aeroborne electromagnetic method (AEM) is an electromagnetic detection technology based on an aerospace flight platform. It uses the platform to place the entire loop source transceiver in the air to observe electromagnetic signals. It has the advantages of flexibility, wide detection range, low cost, and high efficiency. Therefore, it is widely used in the detection of various types of resources such as underground minerals, oil and gas resources, and water resources, as well as in the detection of various underground man-made and non-man-made structures.

[0003] In the process of realizing the concept of the present invention, the inventors found that the aerial detection system in the related technology has a shallow detection blind spot, and it is difficult to achieve airborne electric field measurement and synchronous observation of multi-component electromagnetic signals, which leads to limitations in the detection accuracy and range of the target detection area. Summary of the Invention

[0004] In view of this, the present invention provides a multi-parameter MIMO aviation time-frequency detection system and method.

[0005] One aspect of the present invention provides a multi-parameter MIMO aviation time-frequency detection system, including a flight platform, a transmitting subsystem, a receiving subsystem, and a measurement and control subsystem. The transmitting subsystem and the receiving subsystem are hoisted under the flight platform, wherein the transmitting subsystem includes a first current transmitter, a second current transmitter, a transmitting coil, and a compensation coil. The transmitting subsystem is configured to load a first current pulse into the transmitting coil through the first current transmitter to achieve a primary electromagnetic field excitation, and to load a second current pulse into the compensation coil through the second current transmitter to achieve a compensation electromagnetic field excitation. The primary electromagnetic field acts on different depths of the target detection area. The secondary electromagnetic field response is generated after the underground medium is detected; the receiving subsystem is configured to sample the first current pulse and the second current pulse and collect the secondary electromagnetic field response to transmit it to the measurement and control subsystem for data processing to obtain the electrical information of the underground medium in the target detection area; the measurement and control subsystem is configured to issue control instructions to the transmitting subsystem and the receiving subsystem according to the sampling results and the set detection parameters and monitor the working status of the detection system, so that during the detection process, the measurement and control subsystem adjusts the first current pulse and the second current pulse in real time so that the compensating electromagnetic field can offset the primary electromagnetic field signal doped in the secondary electromagnetic field response, thereby realizing adaptive compensation.

[0006] According to an embodiment of the present invention, by changing the set parameters of the first current pulse and / or the second current pulse, the transmitting coil excites a primary electromagnetic field suitable for achieving deep and shallow detection according to a set timing, and the compensation coil synchronously excites a compensation magnetic field to offset the primary electromagnetic field interference acting on the receiving subsystem; the set parameters include the frequency, amplitude, width, waveform, flow direction and timing of the current pulse.

[0007] According to an embodiment of the present invention, the receiving subsystem includes a magnetic field sensor, an electric field sensor, and an electromagnetic data receiver; the secondary electromagnetic field response data includes a magnetic field signal and an electric field signal; wherein the magnetic field sensor is configured to receive a three-component magnetic field signal, and the electric field sensor is configured to receive a horizontal component electric field signal.

[0008] According to an embodiment of the present invention, the transmitting coil and the compensation coil are both constructed in a ring shape and are concentrically arranged in the same plane. The compensation coil is smaller than the transmitting coil, and the magnetic field sensor is arranged at the center of the compensation coil. By acquiring the primary electromagnetic field interference at the magnetic field sensor in real time, the second current pulse is adjusted so that the compensation coil excites a compensation electromagnetic field to offset the primary electromagnetic field interference.

[0009] According to an embodiment of the present invention, the electric field sensor is a horizontal component capacitive electric field sensor, including: an x-component electric field sensor, used to measure the x-component electric field signal in the direction parallel to the detection system survey line; and a y-component electric field sensor, used to measure the y-component electric field signal in the direction perpendicular to the detection system survey line.

[0010] According to an embodiment of the present invention, the magnetic field sensor is a three-component coil magnetic field sensor, including: an x-component magnetic field sensor, which is constructed in a circular shape, and the normal direction of the circular plane points to the x direction in the geographic Cartesian coordinate system, and is used to measure the x-component magnetic field in the magnetic field signal; a y-component magnetic field sensor, which is constructed in a circular shape, and the normal direction of the circular plane points to the y direction in the geographic Cartesian coordinate system, and is used to measure the y-component magnetic field in the magnetic field signal; and a z-component magnetic field sensor, which is constructed in a circular shape, and the normal direction of the circular plane points to the z direction in the geographic Cartesian coordinate system, and is used to measure the z-component magnetic field in the magnetic field signal; wherein the x-component magnetic field sensor, the y-component magnetic field sensor and the z-component magnetic field sensor are nested and fixedly connected to each other through a connecting device and are placed in a spherical protective cover.

[0011] According to an embodiment of the present invention, an electromagnetic data receiver includes: a signal conditioning module, a signal acquisition module, a main control module, and a data transmission module, wherein: the signal conditioning module includes a first signal conditioning module for filtering and amplifying the received magnetic field signal, and a second signal conditioning module for filtering and amplifying the received electric field signal; the signal acquisition module is configured to perform real-time data sampling on the transmitting coil, the compensation coil, and the signal conditioning module respectively; the main control module is configured to receive the real-time data sampling results and transmit them to the measurement and control subsystem, so that the measurement and control subsystem adjusts the first current pulse and the second current pulse in real time according to the real-time data sampling results.

[0012] According to an embodiment of the present invention, a first current transmitter includes a first drive circuit, a first waveform controller, a first power inverter circuit, a first constant voltage double clamp circuit, and a first current detection circuit. The first power inverter circuit unit is configured to generate a first current pulse with set parameters under the action of the first drive circuit, the first waveform controller, and the first constant voltage double clamp circuit unit, and load it into the transmitting coil. The second current transmitter includes a second drive circuit, a second waveform controller, a second power inverter circuit, a second constant voltage double clamp circuit, and a second current detection circuit. The second power inverter circuit unit is configured to generate a second current pulse with set parameters under the action of the second drive circuit, the second waveform controller, and the second constant voltage double clamp circuit unit, and load it into the compensation coil. The first current detection circuit and the second current detection circuit are used to respectively detect the parameters of the first current pulse and the second current pulse signals in the transmitting coil and the compensation coil in real time. The current transmission control unit is configured to control the operation of the first current transmitter and the second current transmitter under the control instructions issued by the monitoring subsystem.

[0013] According to an embodiment of the present invention, the electrical property information of the underground medium in the target detection area is obtained by performing joint inversion of electric field and magnetic field data on secondary electromagnetic field response data, and the joint inversion includes: setting an initial resistivity model, where the resistivity model is a resistivity-depth imaging resistivity model; using the magnetic field and electric field response forward models to respectively calculate the errors between the magnetic field response and electric field response of the initial resistivity model and the observed magnetic field response and electric field response, to obtain a magnetic field response error and an electric field response error; using the forward model and the resistivity model to construct a Jacobian matrix for inversion of magnetic field and electric field data, and using the magnetic field response error and the electric field response error to respectively calculate the model update amount for inversion of magnetic field data and the model update amount for inversion of electric field data; adding the model update amount and the model parameters to obtain an updated resistivity model; and performing iterative updates until the fitting error of the forward electric field and magnetic field response data of the updated resistivity model is less than a set threshold.

[0014] Another aspect of the present invention provides a multi-parameter MIMO airborne time-frequency detection method, including: loading a first current pulse into a transmitting coil to achieve primary electromagnetic field excitation, and the primary electromagnetic field acts on underground media at different depths in a target detection area to generate a secondary electromagnetic field response; loading a second current pulse into a compensation coil to achieve compensatory electromagnetic field excitation; collecting the first current pulse, the second current pulse, and the secondary electromagnetic field response data and performing data processing; issuing control instructions and monitoring the working status of the detection system based on the data processing results and set detection parameters; adjusting the first current pulse and the second current pulse in real time so that the compensatory electromagnetic field can offset the primary electromagnetic field signal doped in the secondary electromagnetic field response to achieve adaptive compensation; and performing joint inversion of electric field and magnetic field data based on the secondary electromagnetic field response data to obtain electrical information of the underground medium in the target detection area.

[0015] According to an embodiment of the present invention, the transmitting subsystem loads a first current pulse into the transmitting coil through a first current transmitter to realize primary electromagnetic field excitation, and loads a second current pulse into the compensation coil through a second current transmitter to realize compensation electromagnetic field excitation. The primary electromagnetic field acts on the underground medium at different depths in the target detection area to generate a secondary electromagnetic field response. The receiving subsystem samples the first current pulse and the second current pulse and collects the secondary electromagnetic field response to transmit it to the measurement and control subsystem for data processing to obtain the electrical information of the underground medium in the target detection area. The measurement and control subsystem issues control instructions to the transmitting subsystem and the receiving subsystem according to the sampling results and the set detection parameters and monitors the working status of the detection system. Therefore, during the detection process, the measurement and control subsystem adjusts the first current pulse and the second current pulse in real time so that the compensation electromagnetic field can offset the primary electromagnetic field signal doped in the secondary electromagnetic field response, thereby realizing adaptive compensation. Since the secondary electromagnetic field response is generated after the primary electromagnetic field acts on the underground medium at different depths in the target detection area, it is possible to simultaneously obtain multi-component electromagnetic field data while taking into account the different depths of the target detection area; at the same time, the measurement and control subsystem sends control instructions to the transmitting subsystem and the receiving subsystem, adjusting the first current pulse and the second current pulse in real time so that the compensation electromagnetic field can offset the primary electromagnetic field signal mixed in the secondary electromagnetic field response, reducing the electromagnetic interference of the primary field, and obtaining relatively pure multi-component magnetic field data. This avoids the use of the primary field compensation method of the related technology of directly connecting the transmitting coil and the compensation coil in series, and realizes adaptive compensation, thereby making the electrical information of the underground medium in the target detection area obtained by analysis more accurate. Therefore, it effectively solves the technical problems in the related technology of shallow blind spots in the electromagnetic detection of the target detection area and the single electromagnetic corresponding parameters. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The above and other objects, features and advantages of the present invention will become more apparent through the following description of the embodiments of the present invention with reference to the accompanying drawings, in which:

[0017] Figure 1 Schematic diagram of a multi-parameter MIMO aviation time-frequency sounding system according to an embodiment of the present invention.

[0018] Figure 2 Schematic diagram of the structure of the flight platform, transmitting subsystem and receiving subsystem according to an embodiment of the present invention.

[0019] Figure 3 2 is a schematic diagram showing the principle of adaptive compensation for a multi-parameter MIMO aviation time-frequency sounding system according to an embodiment of the present invention.

[0020] Figure 4 2 is a schematic diagram of the circuit principle of a multi-parameter MIMO aviation time-frequency detection system according to an embodiment of the present invention.

[0021] Figure 5 Schematic diagram of waveforms of received and transmitted signals of a multi-parameter MIMO aviation time-frequency detection system according to an embodiment of the present invention.

[0022] Figure 6 Schematic diagram of obtaining underground dielectric electrical information of a target detection area through joint inversion according to an embodiment of the present invention.

[0023] Figure 7 The flowchart of the multi-parameter MIMO aviation time-frequency detection method according to an embodiment of the present invention is schematically shown. DETAILED DESCRIPTION

[0024] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present invention. In the following detailed description, for ease of explanation, many specific details are set forth to provide a comprehensive understanding of embodiments of the present invention. However, it is apparent that one or more embodiments may also be implemented without these specific details. In addition, in the following description, descriptions of known structures and technologies are omitted to avoid unnecessary confusion of the concept of the present invention.

[0025] The terms used herein are only for describing specific embodiments and are not intended to limit the present invention. The terms "comprise", "include", etc. used herein indicate the presence of the features, steps, operations and / or components, but do not exclude the presence or addition of one or more other features, steps, operations or components.

[0026] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification and should not be interpreted in an idealized or overly rigid manner.

[0027] When expressions such as "at least one of A, B, and C, etc." are used, they should generally be interpreted in accordance with the meaning commonly understood by those skilled in the art (for example, "a system having at least one of A, B, and C" should include but is not limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc.).

[0028] In the embodiments of the present invention, the collection, updating, analysis, processing, use, transmission, provision, disclosure, storage, etc. of the data involved (for example, including but not limited to surveying and mapping information, user personal information) all comply with the provisions of relevant laws and regulations, are used for legitimate purposes, and do not violate public order and good morals.

[0029] The basic principle of airborne electromagnetics is to use a single-turn or multi-turn ungrounded loop or a long grounded wire as a transmitting antenna to emit a primary pulsed magnetic field into the ground. During the pauses between pulses, a receiving coil or grounded electrode is used to observe the secondary eddy current field induced in the subsurface medium. By measuring the temporal variation of the secondary field, spatial distribution information at different depths is obtained. Airborne electromagnetics is primarily categorized into full-airborne and semi-airborne modes, depending on the instrument platform. Full-airborne electromagnetics uses an integrated electromagnetic field transmitter and receiver on a flying platform. An airborne transmitting loop source is used to generate a primary pulsed magnetic field (referred to as the primary field). Airborne electromagnetic sensors then use high-sensitivity observations of the secondary electromagnetic field responses (referred to as the secondary field) generated by anomalous underground electrical properties. By processing and inverting the received data, the dielectric properties of the subsurface targets or objects in the detection area are determined.

[0030] However, in order to achieve a greater detection depth, the relevant technology uses periodic large current emission to achieve a larger emission magnetic moment, so it is unable to take into account shallow detection, resulting in a shallow detection blind spot. At the same time, the relevant technology is restricted by sensor technology and can only observe magnetic field signals in the air. It is difficult to measure the electric field in the air, and it is difficult to achieve simultaneous observation of electromagnetic signals of multiple parameters, resulting in insufficient recognition of underground target detection areas. In addition, while achieving large magnetic moment emission, in order to solve the problem of unsaturated received signals, the relevant technology generally uses primary field compensation technology to compensate the strong primary field between transmission and reception to zero, and obtain a pure secondary field response signal to provide high-quality data guarantee for subsequent electromagnetic data processing and target detection and identification. However, during actual flight, the compensation coil will undergo geometric deformation, resulting in the inability to fully compensate the primary field, which makes the remaining primary field affect the detection effect.

[0031] In view of this, an embodiment of the present invention provides a multi-parameter MIMO aviation time-frequency detection system, including a flight platform, a transmitting subsystem, a receiving subsystem, and a measurement and control subsystem. The transmitting subsystem and the receiving subsystem are hoisted under the flight platform, wherein the transmitting subsystem includes a first current transmitter, a second current transmitter, a transmitting coil, and a compensation coil. The transmitting subsystem is configured to load a first current pulse into the transmitting coil through the first current transmitter to achieve a primary electromagnetic field excitation, and to load a second current pulse into the compensation coil through the second current transmitter to achieve a compensation electromagnetic field excitation. The primary electromagnetic field acts on different target detection areas. The receiving subsystem is configured to sample the first current pulse and the second current pulse and collect the secondary electromagnetic field response to transmit the data to the measurement and control subsystem for data processing to obtain the electrical information of the underground medium in the target detection area; the measurement and control subsystem is configured to issue control instructions to the transmitting subsystem and the receiving subsystem according to the sampling results and the set detection parameters and monitor the working status of the detection system, so that during the detection process, the measurement and control subsystem adjusts the first current pulse and the second current pulse in real time so that the compensating electromagnetic field can offset the primary electromagnetic field signal doped in the secondary electromagnetic field response, thereby realizing adaptive compensation.

[0032] Figure 1 The following schematically shows a schematic diagram of a multi-parameter MIMO aviation time-frequency detection system according to an embodiment of the present invention.

[0033] like Figure 1 As shown, the embodiment 100 includes a flight platform 110, a transmitting subsystem 120, a receiving subsystem 130, and a measurement and control subsystem 140. The transmitting subsystem 120 includes a first current transmitter Tx1, a second current transmitter Tx2, a transmitting coil 121, and a compensation coil 122.

[0034] According to an embodiment of the present invention, flight platform 110 can be a helicopter, a fixed-wing aircraft, a multi-rotor aircraft, an unmanned aerial vehicle, or the like. Preferably, flight platform 110 is a helicopter, and the flight of flight platform 110 is controlled by a flight crew. The specific structure and performance parameters can be set according to actual needs and are not limited herein. Flight platform flight parameters include altitude, speed, and route. Prior to conducting aerial detection, each device in the system is assembled and debugged, and self-tests are performed to complete flight safety testing of the flight platform, ensuring the flight safety of the flight platform's multi-parameter MIMO aerial time-frequency detection system during operation.

[0035] According to an embodiment of the present invention, the transmitting subsystem 120 and the receiving subsystem 130 can be hoisted under the flight platform 110 through a pod support device. The pod support device includes a signal cable and a rope composite cable. The signal cable and the rope composite cable are used to connect the first current transmitter, the second current transmitter and the transmitting coil, and the first current transmitter, the second current transmitter and the compensation coil. The pod support device also includes a coil support frame for installing and fixing multiple turns of the transmitting coil and the compensation coil, and maintaining a certain posture during the flight to provide a guarantee for the subsequent acquisition of stable data.

[0036] According to an embodiment of the present invention, the transmitting coil 121 and the compensating coil 122 are both wound with multiple turns of copper wire and are bundled in a glass fiber tube to maintain the coil shape and ensure power-on safety.

[0037] According to an embodiment of the present invention, the measurement and control subsystem 140 may be set on the ground, or may be set in the flying platform 110 or other aerial platforms.

[0038] According to an embodiment of the present invention, the first and second current transmitters are directly powered by the flight platform's generator. The first current transmitter Tx1 is used to provide a first current pulse consisting of a continuous current waveform to the transmitting coil, achieving primary electromagnetic field excitation in the underground medium. The second current transmitter Tx2 is used to provide an adaptive compensation current to the compensation coil to achieve compensatory electromagnetic field excitation. The currents passing through the compensation coil and the transmitting coil are in opposite directions. The primary electromagnetic field acts on the underground medium at different depths in the target detection area, generating a secondary electromagnetic field response. The compensation electromagnetic field can offset the primary electromagnetic field signal mixed in the secondary electromagnetic field response, achieving adaptive compensation.

[0039] According to an embodiment of the present invention, the primary electromagnetic field can cause the underground dielectric structure to generate induced eddy currents. The electric field and magnetic field signals of the secondary electromagnetic field response generated by the induced eddy currents can be collected by the multi-channel receiving subsystem and transmitted to the measurement and control subsystem for processing to obtain the underground dielectric electrical information of the target detection area.

[0040] According to an embodiment of the present invention, the measurement and control subsystem includes a control unit and a monitoring unit. The control unit is used to send operating instructions such as start, continue, and pause to the detection system, and the monitoring unit is used to monitor the detection system's status, electric field data, magnetic field data, and other information such as position and altitude in real time. The measurement and control subsystem adjusts the first and second current pulses in real time so that the compensating electromagnetic field can offset the primary electromagnetic field signal contaminated by the secondary electromagnetic field response, resulting in a pure secondary electromagnetic field. This reduces the electromagnetic field interference of the transmitting subsystem on the receiving subsystem and achieves adaptive compensation.

[0041] According to an embodiment of the present invention, the detection system further includes: a positioning subsystem for real-time positioning of the flight platform to obtain the latitude and longitude information of the flight platform; and a radar altimeter for measuring the flight altitude of the flight platform.

[0042] According to an embodiment of the present invention, the transmitting subsystem loads a first current pulse into the transmitting coil through a first current transmitter to realize primary electromagnetic field excitation, and loads a second current pulse into the compensation coil through a second current transmitter to realize compensation electromagnetic field excitation. The primary electromagnetic field acts on the underground medium at different depths in the target detection area to generate a secondary electromagnetic field response. The receiving subsystem samples the first current pulse and the second current pulse and collects the secondary electromagnetic field response to transmit it to the measurement and control subsystem for data processing to obtain the electrical information of the underground medium in the target detection area. The measurement and control subsystem issues control instructions to the transmitting subsystem and the receiving subsystem according to the sampling results and the set detection parameters and monitors the working status of the detection system. Therefore, during the detection process, the measurement and control subsystem adjusts the first current pulse and the second current pulse in real time so that the compensation electromagnetic field can offset the primary electromagnetic field signal doped in the secondary electromagnetic field response, thereby realizing adaptive compensation. Since the secondary electromagnetic field response is generated after the primary electromagnetic field acts on the underground medium at different depths in the target detection area, it is possible to simultaneously obtain multi-component electromagnetic field data while taking into account the different depths of the target detection area; at the same time, the measurement and control subsystem sends control instructions to the transmitting subsystem and the receiving subsystem, adjusting the first current pulse and the second current pulse in real time so that the compensation electromagnetic field can offset the primary electromagnetic field signal mixed in the secondary electromagnetic field response, reducing the electromagnetic interference of the primary field, and obtaining relatively pure multi-component magnetic field data. This avoids the use of the primary field compensation method of the related technology of directly connecting the transmitting coil and the compensation coil in series, and realizes adaptive compensation, thereby making the electrical information of the underground medium in the target detection area obtained by analysis more accurate. Therefore, it effectively solves the technical problems in the related technology of shallow blind spots in the electromagnetic detection of the target detection area and the single electromagnetic corresponding parameters.

[0043] According to an embodiment of the present invention, Figure 1 As shown, the receiving subsystem 130 includes a magnetic field sensor 131, electric field sensors 132 (1), 132 (2), and an electromagnetic data receiver 133; the secondary electromagnetic field response data includes a magnetic field signal and an electric field signal; wherein the magnetic field sensor is configured to receive a three-component magnetic field signal, and the electric field sensor is configured to receive a horizontal component electric field signal.

[0044] According to an embodiment of the present invention, the magnetic field sensor is configured to receive three-component magnetic field signals, each corresponding to a different spatial direction, enabling the receiving subsystem to comprehensively acquire magnetic field data. The electric field sensor can employ a capacitive design to enable in-flight measurement of multi-component electric field data for an electrical source transient detection system. Consequently, the flying platform can simultaneously acquire multi-component electric and magnetic field data with a single aerial operation.

[0045] According to an embodiment of the present invention, the electric field sensor is a horizontal component capacitive electric field sensor, including: an x-component electric field sensor, used to measure the x-component electric field signal in the direction parallel to the detection system survey line; and a y-component electric field sensor, used to measure the y-component electric field signal in the direction perpendicular to the detection system survey line.

[0046] According to an embodiment of the present invention, the x-component electric field sensor and the y-component electric field sensor have the same performance parameters and are connected to the outside of the support structure of the transmitting coil through a connecting skeleton. The x-component electric field sensor and the y-component electric field sensor can be located 1.5 m to 2 m outside the edge of the transmitting coil.

[0047] According to an embodiment of the present invention, the horizontal component capacitive x-component electric field sensor and the y-component electric field sensor can respectively measure the x-component electric field signal in the direction of the parallel detection system measurement line and the y-component electric field signal in the direction of the vertical detection system measurement line. The x-component electric field sensor and the y-component electric field sensor can be capacitive electric field sensors. Since a non-contact measurement principle is adopted, the x-component and y-component electric field signals in the air can be measured very conveniently without grounding.

[0048] According to an embodiment of the present invention, the magnetic field sensor is a three-component coil magnetic field sensor, including: an x-component magnetic field sensor, which is constructed in a circular shape, and the normal direction of the circular plane points to the x direction in the geographic Cartesian coordinate system, and is used to measure the x-component magnetic field in the magnetic field signal; a y-component magnetic field sensor, which is constructed in a circular shape, and the normal direction of the circular plane points to the y direction in the geographic Cartesian coordinate system, and is used to measure the y-component magnetic field in the magnetic field signal; and a z-component magnetic field sensor, which is constructed in a circular shape, and the normal direction of the circular plane points to the z direction in the geographic Cartesian coordinate system, and is used to measure the z-component magnetic field in the magnetic field signal; wherein the x-component magnetic field sensor, the y-component magnetic field sensor and the z-component magnetic field sensor are nested and fixedly connected to each other through a connecting device and are placed in a spherical protective cover.

[0049] According to an embodiment of the present invention, the transmitting coil, the compensation coil, and the z-component magnetic field sensor are coplanar in a horizontal plane, the x-component magnetic field sensor and the y-component magnetic field sensor are orthogonal to the horizontal plane, and the x-component magnetic field sensor and the y-component electric field sensor are in the same horizontal plane as the transmitting coil and the compensation coil. The x-component magnetic field sensor, the y-component magnetic field sensor, and the z-component magnetic field sensor are orthogonal to each other and are nested and fixedly connected to each other via a connecting device and then placed within a spherical protective cover.

[0050] According to embodiments of the present invention, a circular magnetic field sensor can uniformly capture changes in the magnetic field. The x-component, y-component, and z-component magnetic field sensors are nested and fixedly connected via a connecting device and then placed within a spherical protective cover, effectively preventing external interference with the magnetic field sensors. Furthermore, the flight platform can measure three-component magnetic field signals in a single flight, resolving the technical challenge of achieving real-time measurement of multi-component magnetic field signals in related technologies.

[0051] According to an embodiment of the present invention, by changing the set parameters of the first current pulse and / or the second current pulse, the transmitting coil excites a primary electromagnetic field suitable for achieving deep and shallow detection according to a set timing, and the compensation coil synchronously excites a compensation magnetic field to offset the primary electromagnetic field interference acting on the receiving subsystem; the set parameters include the frequency, amplitude, width, waveform, flow direction and timing of the current pulse.

[0052] According to an embodiment of the present invention, the first current transmitter and the second current transmitter can generate first current pulses and second current pulses with different set parameters according to actual needs, and load them into the transmitting coil and the compensation coil respectively to form different excitation electromagnetic fields.

[0053] According to an embodiment of the present invention, the first current pulse can enable the aerial transmitting coil to generate a primary electromagnetic field with different frequency bands and a wide bandwidth, while stimulating shallow and deep field sources in the underground medium to generate a secondary electromagnetic field with a relatively strong signal.

[0054] Figure 3 The schematic diagram schematically shows the principle of adaptive compensation of a multi-parameter MIMO aviation time-frequency sounding system according to an embodiment of the present invention.

[0055] According to an embodiment of the present invention, the measurement and control subsystem detects data from the receiving subsystem in real time based on the relationship between the number of turns of the transmitting coil and the compensation coil, and adaptively adjusts the amplitude of the current pulse passing through the transmitting coil and / or the compensation coil, so that the compensation coil excites a compensation electromagnetic field to offset the primary electromagnetic field interference acting on the magnetic field sensor. The current passing through the compensation coil is in opposite directions to the transmitting coil, so that the primary electromagnetic field interference in the receiving coil of the z-component magnetic field sensor approaches zero, thereby obtaining pure secondary magnetic field response data.

[0056] According to an embodiment of the present invention, ideally, the amplitude of the first current pulse loaded into the transmitting coil is I T The second current pulse amplitude I loaded into the compensation coil B When the magnitude relationship of satisfies the following formula (1), the compensation magnetic field synchronously excited by the compensation coil can offset the primary electromagnetic field interference acting on the receiving subsystem.

[0057] (1);

[0058] Among them, N T Indicates the number of turns of the transmitting coil, R T Indicates the radius of the transmitting coil, N B Indicates the number of turns of the compensation coil, R B Indicates the radius of the compensation coil.

[0059] According to an embodiment of the present invention, the measurement and control subsystem achieves primary electromagnetic field excitation for deep detection and shallow detection by adjusting the frequency, amplitude, width, waveform, flow direction and timing of the first current pulse and / or the second current pulse, ensuring that the compensation magnetic field is accurately matched with the electromagnetic field generated by the transmitting coil in time and space, and enables the compensation coil to synchronously excite the compensation magnetic field to offset the primary electromagnetic field interference acting on the receiving subsystem, thereby performing efficient and accurate detection of the target detection area.

[0060] According to an embodiment of the present invention, the transmitting coil and the compensation coil are both constructed in a ring shape and are concentrically arranged in the same plane. The compensation coil is smaller than the transmitting coil, and the magnetic field sensor is arranged at the center of the compensation coil. By acquiring the primary electromagnetic field interference at the magnetic field sensor in real time, the second current pulse is adjusted so that the compensation coil excites a compensation electromagnetic field to offset the primary electromagnetic field interference.

[0061] According to an embodiment of the present invention, the transmitting coil and the compensation coil may be in the shape of a circular ring, or in the shape of a regular polygonal ring, such as a regular 20-sided ring.

[0062] According to an embodiment of the present invention, the compensation coil is smaller than the transmitting coil, ensuring a maximum compensation effect at the location of the magnetic field sensor.

[0063] According to an embodiment of the present invention, the magnetic field sensor is disposed at the center of the compensation coil, which helps to improve the accuracy and signal-to-noise ratio of the magnetic field data.

[0064] To better understand the relative positions of the flight platform, the transmitting subsystem, and the receiving subsystem of the multi-parameter MIMO aviation time-frequency detection system according to the embodiment of the present invention, the following will be described. Figure 2 The relative positions of the flight platform, transmitting subsystem and receiving subsystem are explained.

[0065] Figure 2 The structure diagram of the flying platform, the transmitting subsystem and the receiving subsystem according to the embodiment of the present invention is schematically shown.

[0066] like Figure 2 As shown, embodiment 200 includes a flight platform 110, a transmitting subsystem, and a receiving subsystem. The transmitting subsystem includes a first current transmitter Tx1, a second current transmitter Tx2, a transmitting coil 121, and a compensation coil 122. The receiving subsystem 130 includes a magnetic field sensor 131, an x-component electric field sensor 132 (1), a y-component electric field sensor 132 (2), and an electromagnetic data receiver 133.

[0067] Figure 4 The circuit principle diagram of the multi-parameter MIMO aviation time-frequency detection system according to an embodiment of the present invention is schematically shown.

[0068] According to an embodiment of the present invention, Figure 4 As shown, the first current transmitter Tx1 includes a first driving circuit, a first waveform controller, a first power inverter circuit, a first constant voltage double clamp circuit, and a first current detection circuit. The first power inverter circuit unit is configured to generate a first current pulse with set parameters under the action of the first driving circuit, the first waveform controller, and the first constant voltage double clamp circuit unit, and load it into the transmitting coil; the second current transmitter Tx2 includes a second driving circuit, a second waveform controller, a second power inverter circuit, a second constant voltage double clamp circuit, and a second current detection circuit, wherein: the second power inverter circuit unit is configured to generate a second current pulse with set parameters under the action of the second driving circuit, the second waveform controller, and the second constant voltage double clamp circuit unit, and load it into the compensation coil; the first current detection circuit and the second current detection circuit are used to respectively detect the parameters of the first current pulse and the second current pulse signal in the transmitting coil and the compensation coil in real time; the current transmission control unit is configured to control the operation of the first current transmitter and the second current transmitter under the control instructions issued by the monitoring subsystem.

[0069] According to an embodiment of the present invention, the first current transmitter further includes a DC / DC high-power power supply conversion circuit for supplying power to the first drive circuit, the first waveform controller, and the first power inverter circuit, and converting the DC power supply voltage.

[0070] According to an embodiment of the present invention, the second current transmitter further includes a DC / DC high-power power supply conversion circuit for supplying power to the second drive circuit, the second waveform controller, and the second power inverter circuit, and converting the DC supply voltage.

[0071] According to an embodiment of the present invention, the first constant voltage double clamp circuit unit is used to simultaneously clamp the rising and falling edges of the first current pulse emitted by the first current transmitter to improve the linearity and slope of the current edge and reduce the turn-off time.

[0072] According to an embodiment of the present invention, the second constant voltage double clamp circuit unit is used to simultaneously clamp the rising and falling edges of the second current pulse emitted by the second current transmitter to improve the linearity and slope of the current edge and reduce the turn-off time.

[0073] According to an embodiment of the present invention, the first current detection circuit and the second current detection circuit may be high-precision current detection circuits for detecting the waveforms of the generated first current pulse and the second current pulse.

[0074] According to an embodiment of the present invention, an electromagnetic data receiver includes: a signal conditioning module, a signal acquisition module, a main control module, and a data transmission module, wherein: the signal conditioning module includes a first signal conditioning module for filtering and amplifying the received magnetic field signal, and a second signal conditioning module for filtering and amplifying the received electric field signal; the signal acquisition module is configured to perform real-time data sampling on the transmitting coil, the compensation coil, and the signal conditioning module respectively; the main control module is configured to receive the real-time data sampling results and transmit them to the measurement and control subsystem, so that the measurement and control subsystem adjusts the first current pulse and the second current pulse in real time according to the real-time data sampling results.

[0075] According to an embodiment of the present invention, the electromagnetic data receiver also includes a data storage module for real-time storage of sampling results, which can effectively prevent data loss. The main control module can, for example, maintain the synchronization of data reception and transmission between various modules based on the Beidou navigation system or GPS (Global Positioning System) or optical fiber transmission, and realize the upload, download and deletion of control instructions of the measurement and control subsystem.

[0076] According to an embodiment of the present invention, the signal acquisition module may be an analog-to-digital converter circuit capable of converting analog signals from the first signal conditioning module and the second signal conditioning module into digital signals.

[0077] like Figure 4As shown, the receiving subsystem collects electric and magnetic field signals using a three-component magnetic field sensor and a horizontal capacitive electric field sensor. The first signal conditioning module performs gain preprocessing on the received magnetic field signal, while the second signal conditioning module performs gain preprocessing on the received electric field signal. The first and second signal conditioning modules simultaneously filter and amplify the electromagnetic signals. The coil signal acquisition module, magnetic field signal acquisition module, and electric field signal acquisition module are used to perform real-time, synchronous sampling of the transmitting coil and compensation coil, the first signal conditioning module, and the second signal conditioning module, respectively.

[0078] Figure 5 The waveform diagram of the received signal and the transmitted signal of the multi-parameter MIMO aviation time-frequency detection system according to the embodiment of the present invention is schematically shown.

[0079] like Figure 5 As shown, the horizontal axis is time, and the time includes a set timing. The transmitting subsystem transmits the first current pulse and the second current pulse according to the set timing.

[0080] In the S1 state, the first current transmitter generates a 1.25 Hz to 25 Hz time domain bipolar square wave first current pulse input into the transmitting coil, with an amplitude of up to 200 A to 300 A. The receiving subsystem simultaneously acquires multi-parameter, multi-channel three-component magnetic field signals and horizontal electric field signals for deep exploration.

[0081] In the S3 state, the first current transmitter generates a multi-frequency first current pulse in the frequency domain of 1 Hz to 20 kHz and inputs it into the transmitting coil. The amplitude can reach 10 A to 50 A. The receiving subsystem synchronously collects multi-parameter, multi-channel three-component magnetic field signals and horizontal electric field signals for shallow detection.

[0082] In the S2 and S4 states, the transmitting coil does not work. The purpose of setting this state is to wait for the excitation of the first current pulse and the second current pulse to end.

[0083] Figure 6 A schematic diagram of obtaining underground dielectric electrical property information of a target detection area through joint inversion according to an embodiment of the present invention is schematically shown.

[0084] According to an embodiment of the present invention, the electrical property information of the underground medium in the target detection area is obtained by performing joint inversion of electric field and magnetic field data on secondary electromagnetic field response data, and the joint inversion includes: setting an initial resistivity model, where the resistivity model is a resistivity-depth imaging resistivity model; using the magnetic field and electric field response forward models to respectively calculate the errors between the magnetic field response and electric field response of the initial resistivity model and the observed magnetic field response and electric field response, to obtain a magnetic field response error and an electric field response error; using the forward model and the resistivity model to construct a Jacobian matrix for inversion of magnetic field and electric field data, and using the magnetic field response error and the electric field response error to respectively calculate the model update amount for inversion of magnetic field data and the model update amount for inversion of electric field data; adding the model update amount and the model parameters to obtain an updated resistivity model; and performing iterative updates until the fitting error of the forward electric field and magnetic field response data of the updated resistivity model is less than a set threshold.

[0085] According to an embodiment of the present invention, the secondary electromagnetic field response data needs to be preprocessed before the joint inversion. The preprocessing operations include noise filtering, error correction, data stacking, data extraction, and spatial filtering. The specific operations are as follows:

[0086] (1) Noise filtering: The electromagnetic field data collected by the receiving subsystem is subjected to denoising. Alpha-trim (α-truncation) filtering, polynomial fitting, mean filtering, high-flying correction and other related technologies can be used to suppress and remove the atmospheric noise, motion noise, VLF (Very Low Frequency) noise, background noise, power frequency interference, and human environment noise in the electromagnetic field data.

[0087] (2) Error correction: For problems such as transmission waveform stability, attitude effect, and leveling error between measurement lines in the electromagnetic field data in the detection system, relevant correction technologies such as transmission waveform correction, attitude correction, and interactive data dynamic leveling are used.

[0088] (3) Data superposition: After error correction, the multi-component electromagnetic field data are superimposed to eliminate redundant information, reduce the amount of data, and eliminate random noise, which is beneficial to improving the data signal-to-noise ratio.

[0089] (4) Data extraction: Perform approximately logarithmic equal-interval extraction on the multi-component electromagnetic field data in the time domain. No data extraction is required for the electromagnetic field data in the frequency domain.

[0090] (5) Spatial filtering: Use low-pass filtering or trapezoidal waveform to perform spatial filtering on the profile of electromagnetic field data to further improve the data signal-to-noise ratio and obtain high-quality airborne electromagnetic data that can be used for fine inversion and interpretation.

[0091] According to an embodiment of the present invention, resistivity-depth imaging processing is performed on airborne electromagnetic data to obtain resistivity-depth imaging results. A regularized initial resistivity model is constructed based on the resistivity-depth imaging results and prior information such as geology, geophysical exploration, geochemical exploration, remote sensing, and drilling information in the target detection area, thereby preventing the influence of unfounded initial model construction on the inversion results.

[0092] According to an embodiment of the present invention, it is determined whether the fitting error of the forward electric field and magnetic field response data of the updated resistivity model is less than a set threshold. When the fitting error of the forward electric field and magnetic field response data of the resistivity model is less than the set threshold, the inversion calculation is terminated. When the fitting error of the forward electric field and magnetic field response data of the resistivity model is not less than the set threshold, the resistivity model is continued to be iterated, and the model update amount is recalculated. The resistivity model is updated and the judgment operation is repeated until the fitting error of the forward electric field and magnetic field response data of the updated resistivity model is less than the set threshold. The final resistivity model is obtained, the joint inversion is terminated, and the electrical property information of the underground medium in the target detection area is obtained.

[0093] In order to better understand the above joint inversion process, the following will be Figure 6 The preprocessing before the joint inversion process and the process of obtaining the underground medium electrical information of the target detection area based on the inversion results are explained.

[0094] Figure 7 The flowchart of the multi-parameter MIMO aviation time-frequency detection method according to an embodiment of the present invention is schematically shown.

[0095] like Figure 7 As shown, the method 700 includes operations S710 to S760.

[0096] In operation S710, a first current pulse is loaded into a transmitting coil to realize primary electromagnetic field excitation. The primary electromagnetic field acts on underground media at different depths in a target detection area to generate a secondary electromagnetic field response.

[0097] In operation S720 , a second current pulse is applied to the compensation coil to achieve compensation electromagnetic field excitation.

[0098] In operation S730 , the first current pulse, the second current pulse, and the secondary electromagnetic field response data are collected and processed.

[0099] In operation S740 , a control instruction is issued according to the data processing result and the set detection parameters and the working status of the detection system is monitored.

[0100] In operation S750, the first current pulse and the second current pulse are adjusted in real time so that the compensation electromagnetic field can offset the primary electromagnetic field signal mixed in the secondary electromagnetic field response, thereby achieving adaptive compensation.

[0101] In operation S760, electric field and magnetic field data are jointly inverted based on the secondary electromagnetic field response data to obtain underground medium electrical property information in the target detection area.

[0102] It should be noted that the multi-parameter MIMO aviation time-frequency detection method part in the embodiment of the present invention corresponds to the multi-parameter MIMO aviation time-frequency detection system part in the embodiment of the present invention. For the description of the detection method part, please refer to the detection method part and will not be repeated here.

[0103] According to an embodiment of the present invention, a primary electromagnetic field excitation is achieved by loading a first current pulse into a transmitting coil, and a compensating electromagnetic field excitation is achieved by loading a second current pulse into a compensating coil. After the primary electromagnetic field acts on underground media at different depths in the target detection area, a secondary electromagnetic field response is generated. The first current pulse and the second current pulse are sampled, and the secondary electromagnetic field response is collected for data processing to obtain the electrical information of the underground medium in the target detection area. Based on the sampling results and the set detection parameters, control instructions are issued and the working status of the detection system is monitored. Therefore, during the detection process, the measurement and control subsystem adjusts the first current pulse and the second current pulse in real time so that the compensating electromagnetic field can offset the primary electromagnetic field signal doped in the secondary electromagnetic field response, thereby achieving adaptive compensation. Since the secondary electromagnetic field response is generated after the primary electromagnetic field acts on the underground medium at different depths in the target detection area, it is possible to simultaneously obtain multi-component electromagnetic field data while taking into account the different depths of the target detection area; at the same time, the measurement and control subsystem sends control instructions to the transmitting subsystem and the receiving subsystem, adjusting the first current pulse and the second current pulse in real time so that the compensation electromagnetic field can offset the primary electromagnetic field signal mixed in the secondary electromagnetic field response, reducing the electromagnetic interference of the primary field, and obtaining relatively pure multi-component magnetic field data. This avoids the use of the primary field compensation method of the related technology of directly connecting the transmitting coil and the compensation coil in series, and realizes adaptive compensation, thereby making the electrical information of the underground medium in the target detection area obtained by analysis more accurate. Therefore, it effectively solves the technical problems in the related technology of shallow blind spots in the electromagnetic detection of the target detection area and the single electromagnetic corresponding parameters.

[0104] The flowcharts and block diagrams in the accompanying drawings illustrate the possible architectures, functions, and operations of the systems, methods, and computer program products according to various embodiments of the present invention. In this regard, each box in the flowchart or block diagram may represent a module, program segment, or portion of code, which contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the boxes may occur in an order different from that marked in the accompanying drawings. For example, two boxes shown in succession may actually be executed substantially in parallel, or they may sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram or flowchart, as well as the combination of boxes in the block diagram or flowchart, may be implemented using a dedicated hardware-based system that performs the specified function or operation, or may be implemented using a combination of dedicated hardware and computer instructions. It will be understood by those skilled in the art that the features described in the various embodiments of the present invention may be combined and / or coupled in various ways, even if such combinations or couplings are not explicitly described in the present invention. In particular, the features described in the various embodiments of the present invention may be combined and / or coupled in various ways without departing from the spirit and teachings of the present invention. All such combinations and / or combinations fall within the scope of the present invention.

[0105] The above describes embodiments of the present invention. However, these embodiments are for illustrative purposes only and are not intended to limit the scope of the present invention. Although each embodiment has been described separately above, this does not mean that the measures in each embodiment cannot be advantageously used in combination. Without departing from the scope of the present invention, those skilled in the art may make various substitutions and modifications, which should all fall within the scope of the present invention.

Claims

1. A multi-parameter MIMO aviation time-frequency detection system, characterized in that: It includes a flight platform, a transmitting subsystem, a receiving subsystem, and a measurement and control subsystem. The transmitting subsystem and the receiving subsystem are hoisted under the flight platform. The transmitting subsystem includes a first current transmitter, a second current transmitter, a transmitting coil, and a compensation coil. The transmitting subsystem is configured to load a first current pulse into the transmitting coil via the first current transmitter to achieve primary electromagnetic field excitation, and to load a second current pulse into the compensation coil via the second current transmitter to achieve compensation electromagnetic field excitation. The primary electromagnetic field acts on underground media at different depths in a target detection area to generate a secondary electromagnetic field response. The receiving subsystem is configured to sample the first current pulse and the second current pulse and collect the secondary electromagnetic field response, so as to transmit the data to the measurement and control subsystem for data processing and obtain the electrical property information of the underground medium in the target detection area; The measurement and control subsystem is configured to issue control instructions to the transmitting subsystem and the receiving subsystem according to the sampling results and the set detection parameters and monitor the working status of the detection system, so that during the detection process, the measurement and control subsystem adjusts the first current pulse and the second current pulse in real time so that the compensating electromagnetic field can offset the primary electromagnetic field signal mixed in the secondary electromagnetic field response, thereby achieving adaptive compensation; By changing the set parameters of the first current pulse and the second current pulse, the transmitting coil is caused to excite a primary electromagnetic field suitable for achieving deep and shallow detection according to a set time sequence, and the compensation coil is caused to excite a compensation magnetic field synchronously to offset the primary electromagnetic field interference acting on the receiving subsystem; the set parameters include the frequency, amplitude, width, waveform, flow direction and time sequence of the current pulse; In the S1 state, the first current transmitter generates a time domain bipolar square wave first current pulse of 1.25Hz~25Hz, which is input into the transmitting coil, with an amplitude of 200A~300A. The receiving subsystem synchronously collects multi-parameter, multi-channel three-component magnetic field signals and horizontal electric field signals for deep detection; in the S3 state, the first current transmitter generates a frequency domain multi-frequency first current pulse of 1Hz~20kHz, which is input into the transmitting coil, with an amplitude of 10A~50A. The receiving subsystem synchronously collects multi-parameter, multi-channel three-component magnetic field signals and horizontal electric field signals for shallow detection; in the S2 and S4 states, the transmitting coil does not work to wait for the excitation of the first current pulse and the second current pulse to end.

2. The detection system according to claim 1, characterized in that The receiving subsystem includes a magnetic field sensor, an electric field sensor, and an electromagnetic data receiver; the secondary electromagnetic field response data includes a magnetic field signal and an electric field signal; wherein the magnetic field sensor is configured to receive a three-component magnetic field signal, and the electric field sensor is configured to receive a horizontal component electric field signal.

3. The detection system according to claim 2, characterized in that The transmitting coil and the compensating coil are both constructed in a ring shape and are concentrically arranged in the same plane. The compensating coil is smaller than the transmitting coil, and the magnetic field sensor is arranged at the center of the compensating coil. By acquiring the primary electromagnetic field interference at the magnetic field sensor in real time, the second current pulse is adjusted so that the compensating coil excites a compensating electromagnetic field to offset the primary electromagnetic field interference.

4. The detection system according to claim 2, characterized in that The electric field sensor is a horizontal component capacitive electric field sensor, comprising: An x-component electric field sensor is used to measure an x-component electric field signal in a direction parallel to a detection line of the detection system; and The y-component electric field sensor is used to measure the y-component electric field signal in the direction of the vertical detection system survey line.

5. The detection system according to claim 2, characterized in that The magnetic field sensor is a three-component coil magnetic field sensor, comprising: The x-component magnetic field sensor is constructed in a circular shape, with the normal direction of the circular plane pointing to the x-direction in the geographic Cartesian coordinate system, and is used to measure the x-component magnetic field in the magnetic field signal; a y-component magnetic field sensor configured in a circular shape with the normal direction of the circular plane pointing to the y direction in the geographic Cartesian coordinate system, for measuring the y-component magnetic field in the magnetic field signal; and The z-component magnetic field sensor is constructed in a circular shape, with the normal direction of the circular plane pointing to the z direction in the geographic Cartesian coordinate system, and is used to measure the z-component magnetic field in the magnetic field signal; The x-component magnetic field sensor, the y-component magnetic field sensor and the z-component magnetic field sensor are nested and fixedly connected to each other through a connecting device and then placed in the spherical protective cover.

6. The detection system according to any one of claims 3 to 5, characterized in that: The electromagnetic data receiver includes: a signal conditioning module, a signal acquisition module, a main control module, and a data transmission module, wherein: The signal conditioning module includes a first signal conditioning module for filtering and amplifying the received magnetic field signal, and a second signal conditioning module for filtering and amplifying the received electric field signal; The signal acquisition module is configured to perform real-time data sampling on the transmitting coil, the compensation coil, and the signal conditioning module respectively; The main control module is configured to receive real-time data sampling results and transmit the results to the measurement and control subsystem, so that the measurement and control subsystem adjusts the first current pulse and the second current pulse in real time according to the real-time data sampling results.

7. The detection system according to any one of claims 3 to 5, characterized in that: The first current transmitter includes a first driving circuit, a first waveform controller, a first power inverter circuit, a first constant voltage double clamp circuit, and a first current detection circuit. The first power inverter circuit is configured to generate a first current pulse with set parameters under the action of the first driving circuit, the first waveform controller, and the first constant voltage double clamp circuit unit, and load it into the transmitting coil; The second current transmitter includes a second driving circuit, a second waveform controller, a second power inverter circuit, a second constant voltage double clamp circuit, and a second current detection circuit, wherein: The second power inverter circuit unit is configured to generate a second current pulse with set parameters under the action of the second drive circuit, the second waveform controller, and the second constant voltage double clamp circuit unit, and load the second current pulse into the compensation coil; The first current detection circuit and the second current detection circuit are used to respectively detect parameters of the first current pulse and the second current pulse signal in the transmitting coil and the compensation coil in real time; The current transmitter control unit is configured to control the operation of the first current transmitter and the second current transmitter under the control instruction issued by the monitoring subsystem.

8. The detection system according to any one of claims 3 to 5, characterized in that: The electrical property information of the underground medium in the target detection area is obtained by performing a joint inversion of the electric field and magnetic field data on the secondary electromagnetic field response data. The joint inversion includes: Setting an initial resistivity model, wherein the resistivity model is a resistivity-depth imaging resistivity model; The magnetic field response and electric field response forward models are used to calculate the errors between the magnetic field response and electric field response of the initial resistivity model and the observed magnetic field response and electric field response, respectively, to obtain the magnetic field response error and electric field response error; The forward model and resistivity model are used to construct the Jacobian matrices for magnetic field and electric field data inversion. The magnetic field response error and electric field response error are used to calculate the model update amount for magnetic field data inversion and the model update amount for electric field data inversion, respectively. Adding the model update amount and the model parameters to obtain an updated resistivity model; and Iterative updates are performed until the fitting error of the forward electric and magnetic field response data of the updated resistivity model is less than the set threshold.

9. A multi-parameter MIMO aviation time-frequency detection method based on the detection system according to any one of claims 1 to 8, characterized in that: include: Loading a first current pulse into a transmitting coil to achieve primary electromagnetic field excitation, wherein the primary electromagnetic field acts on underground media at different depths in a target detection area to generate a secondary electromagnetic field response; Loading a second current pulse into the compensation coil to achieve compensation electromagnetic field excitation; collecting the first current pulse, the second current pulse, and the secondary electromagnetic field response data and performing data processing; Issue control instructions and monitor the working status of the detection system based on data processing results and set detection parameters; adjusting the first current pulse and the second current pulse in real time so that the compensating electromagnetic field can offset the primary electromagnetic field signal doped in the secondary electromagnetic field response, thereby achieving adaptive compensation; as well as The electric field and magnetic field data are jointly inverted based on the secondary electromagnetic field response data to obtain the electrical property information of the underground medium in the target detection area.

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