A three-component electromagnetic induction probe based on a transceiver split body

Abstract

The application discloses a kind of three-component electromagnetic induction probe based on transceiver split body, including one circular transmitting coil and three mutually orthogonal square receiving coils, transmitting coil is located in the outermost edge of probe, three receiving coils are inside transmitting coil, and it is central symmetry with the center of transmitting coil as center, transmitting coil is electrically connected with transmitting circuit, three receiving coils are electrically connected with three receiving processing circuits respectively, transmitting circuit and three receiving processing circuits are electrically connected with MCU, and probe is powered by power supply circuit.The probe disclosed in the application adopts physical transceiver separation structure and orthogonal non-coplanar three-component receiving coil, combines three-component synchronous measurement with single transmission and multiple reception, obtains full-component time-domain attenuation information of magnetic field vector simultaneously, and greatly enriches the characteristic information amount that can be used for target identification.

Description

Technical Field

[0001] This invention belongs to the field of underground target detection technology, and specifically relates to a three-component electromagnetic induction probe based on a separate transceiver unit, which is suitable for UAV platforms and can perform high-precision three-dimensional positioning and identification of small underground metal targets. Background Technology

[0002] Transient electromagnetic method (TEM) is a widely used geophysical exploration method. Its working principle is as follows: a pulsed primary magnetic field is transmitted underground via a transmitting coil. After the primary magnetic field is suddenly shut off, the secondary eddy current field induced by underground conductors and its decay process are measured, thereby inferring the electrical distribution of the underground medium. This method plays an important role in resource exploration, environmental surveys, and engineering monitoring.

[0003] Currently, mainstream ground-based transient electromagnetic instruments generally employ a single-transmitter-single-receiver loop configuration (such as overlapping loops, central loops, etc.), and typically only acquire a single magnetic field component in the vertical direction. This single-component observation mode has significant drawbacks: First, it acquires a scalar decay curve, which reflects incomplete geoelectric information, leading to severe ambiguity in inversion interpretation; the same data may correspond to multiple different underground structural models. Second, for non-horizontally layered or complex-shaped targets (such as inclined ore bodies, underground pipes, cavities, etc.), single-component data has very weak spatial resolution, making it difficult to achieve accurate three-dimensional characterization. Although this can be improved by increasing the density of measuring points and performing area measurements, this significantly reduces exploration efficiency.

[0004] Existing technologies attempt to obtain more information by rotating the receiving coil or measuring different components at different points. However, this not only makes fieldwork cumbersome and inefficient, but also causes data collected at different times and locations to be inconsistent due to environmental noise and system drift, which brings new difficulties to the comprehensive processing and detailed interpretation of the data. Summary of the Invention

[0005] The technical problem to be solved by this invention is to improve the three-dimensional detection capability of transient electromagnetic methods. To this end, a three-component electromagnetic induction probe based on a transmitter and receiver is provided, which can directly and synchronously acquire the full component information of the secondary magnetic field under single-point excitation conditions.

[0006] The present invention adopts the following technical solution:

[0007] An improved three-component electromagnetic induction probe based on a separate transmitter and receiver is characterized by the following: it includes a circular transmitting coil and three mutually orthogonal square receiving coils. The transmitting coil is located at the outermost edge of the probe, and the three receiving coils are inside the transmitting coil and are centrally symmetrical about the center of the transmitting coil. The transmitting coil is electrically connected to the transmitting circuit, and the three receiving coils are electrically connected to three receiving processing circuits respectively. The transmitting circuit and the three receiving processing circuits are all electrically connected to an MCU, and the probe is powered by a power supply circuit.

[0008] Furthermore, the transmitting coil is made of copper enameled wire with 16-20 turns, an inductance of 450μH ±100μH, and a DC resistance of 670mΩ ±70mΩ. The transmitting coil is connected to the transmitting circuit through two wires.

[0009] Furthermore, the transmitting circuit includes a high-speed optocoupler isolator Q16. The first pin of the high-speed optocoupler isolator Q16 is grounded through resistor R97 and receives MCU signals through resistor R95. The third and fourth pins are grounded, the sixth pin is electrically connected to the 12V voltage input terminal, the fifth pin is grounded through resistor R13, and is electrically connected to the gate of the field-effect transistor through resistor R19, resistor R26, and grounded. The drain of the field-effect transistor is electrically connected to the 12V voltage input terminal through capacitor C25. The two wires of the transmitting coil are respectively connected to the two sides of capacitor C25. The source of the field-effect transistor is grounded through electrolytic capacitor C66 and resistor R98.

[0010] Furthermore, the two sides of capacitor C25 are electrically connected to the two wires of the transmitting coil through electrolytic capacitors C15 and C36, respectively. The two sides of electrolytic capacitor C66 are electrically connected to the 12V voltage input terminal through resistor R25 and electrolytic capacitor C67, respectively. The ground terminal of resistor R98 is electrically connected to the 12V voltage input terminal through diode D6.

[0011] Furthermore, the receiving coils are made of copper enameled wire. The outer first receiving coil has a side length of 26cm, 25 turns, an inductance of 393μH ± 20μH, and a DC resistance of 550mΩ ± 50mΩ. The middle second receiving coil has a side length of 19cm, 27 turns, an inductance of 403μH ± 20μH, and a DC resistance of 536mΩ ± 50mΩ. The inner third receiving coil has a side length of 17cm, 30 turns, an inductance of 394μH ± 20μH, and a DC resistance of 510mΩ ± 50mΩ. The receiving coils are connected to the receiving processing circuit through two wires.

[0012] Furthermore, the three receiving and processing circuits have the same circuit structure, each including a first-stage amplification and filtering circuit, a second-stage controllable differential pair amplification circuit, and a third-stage time window segmentation and integration amplification circuit.

[0013] Furthermore, the first-stage amplification and filtering circuit includes three operational amplifiers U7, U8A, and U8B. The inverting input of operational amplifier U7 is electrically connected to one wire of the receiving coil through an electrolytic capacitor C35. The non-inverting input of operational amplifier U7 is grounded through a diode and through a resistor and an electrolytic capacitor C64. The other wire of the receiving coil is electrically connected to the ground terminal of the electrolytic capacitor C64. The output of operational amplifier U7 is electrically connected to the inverting input of operational amplifier U8A through a resistor R14 and a capacitor C37. The output of operational amplifier U7 is grounded through a capacitor C54. A capacitor C14 and a resistor are connected in parallel between the inverting input and output of operational amplifier U7. R10 connects to ground the non-inverting input of operational amplifier U8A. The output of operational amplifier U8A is electrically connected to the inverting input of operational amplifier U8B via resistors R87 and R91. Capacitor C106 and resistor R96 are connected in parallel between the inverting input and output of operational amplifier U8A. The non-inverting input of operational amplifier U8B is grounded. The output of operational amplifier U8B outputs signal S123 to the two-stage controllable differential pair amplifier circuit via resistor R90 and capacitor C115. The output and inverting input of operational amplifier U8B are electrically connected via capacitor C107. The output of operational amplifier U8B is grounded via resistor R99 and capacitor C111.

[0014] Furthermore, the two-stage controllable differential pair amplifier circuit includes a common-emitter differential pair amplifier circuit composed of transistors Q6 and Q7, a current sink circuit composed of transistors Q3 and Q8 and operational amplifier U9, an adjustable gain circuit composed of operational amplifiers U11A and U11B and transistor Q10, a signal buffer U14, a digital-to-analog converter U15, and a dual-channel analog switch U10. The MCU performs digital-to-analog conversion through U15 and outputs signal S4 to the three-stage time window segmentation and integration amplifier circuit.

[0015] Furthermore, the three-stage time window segmentation and integration amplifier circuit includes an analog switch and three integration amplifier circuits. The input signal S4 is segmented into three observation signals S1, S2 and S3 with different time widths after passing through the analog switch. Each of the three observation signals is output to the MCU after passing through an integration amplifier circuit.

[0016] Furthermore, the power supply circuit has an input voltage of 12V, which is first boosted to 14V, and then the step-down LDO chip outputs 3.3V and ±5V voltages.

[0017] The beneficial effects of this invention are:

[0018] The probe disclosed in this invention employs a physical transmit / receive separation structure and orthogonal, non-coplanar three-component receiving coils, combining simultaneous three-component measurement with single-transmitter, multi-receiver operation. By simultaneously acquiring the full-component time-domain attenuation information of the magnetic field vector, it greatly enriches the amount of feature information available for target identification. This effectively overcomes the shortcomings of traditional single-component or amplitude detection methods in terms of insufficient information dimensionality, significantly improving the ability to perform high-precision classification, identification, and three-dimensional positioning of buried targets in complex geological environments.

[0019] The probe disclosed in this invention can be used in electromagnetic induction detection systems for UAV platforms. It features comprehensive information dimensions, strong three-dimensional spatial resolution, low inversion ambiguity, and high accuracy in identifying complex targets. It can quickly, efficiently, and accurately complete three-dimensional imaging and positioning of underground anomalies, and has important application value in fields such as resource exploration, unexploded ordnance investigation, and archaeological exploration. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the probe structure disclosed in this invention;

[0021] Figure 2 This is a schematic diagram of the structure of the transmitting coil and receiving coil in the probe disclosed in this invention;

[0022] Figure 3 This is a schematic diagram of the circuit connection of the transmitting circuit in the probe disclosed in this invention;

[0023] Figure 4 This is a schematic diagram of the circuit connection of the first-stage amplification and filtering circuit in the probe disclosed in this invention;

[0024] Figure 5 This is a schematic diagram of the circuit connection of the two-stage controllable differential pair amplifier circuit in the probe disclosed in this invention;

[0025] Figure 6 This is a schematic diagram of the circuit connection of the three-stage time window segmentation and integration amplification circuit in the probe disclosed in this invention;

[0026] Figure 7 This is a schematic diagram of the power supply circuit in the probe disclosed in this invention. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0028] Example 1 discloses a three-component electromagnetic induction probe based on a separate transmit and receive structure, employing a transmit and receive separation structure where the transmitting coil and receiving coil are spatially non-coplanar, such as... Figure 1As shown, it includes a circular transmitting coil 1 and three square receiving coils 2 that are orthogonal to each other in pairs. The transmitting coil is located at the outermost edge of the probe, and the three receiving coils are inside the transmitting coil and are centrally symmetrical about the center of the transmitting coil. The transmitting coil is electrically connected to the transmitting circuit, and the transmitting circuit provides sufficient transmitting energy to the transmitting coil to drive the transmitting coil to generate a primary field radiating into the underground space.

[0029] Three receiving coils are electrically connected to three receiving and processing circuits, respectively, for synchronously measuring the gradients of the three orthogonal components of the spatial magnetic field. The transmitting circuit and the three receiving and processing circuits are all electrically connected to the MCU, and the probe is powered by the power supply circuit.

[0030] The probe employs a physically separated inner and outer layer design. The outer layer is an independent transmitting module, with a circular transmitting coil and its supporting structure at its core. The inner layer is an independent receiving module, with three mutually orthogonal square receiving coils at its core (corresponding to the X, Y, and Z axes of a Cartesian coordinate system, respectively). The transmitting and receiving coils are not on the same plane in space, forming a non-coplanar layout.

[0031] The probe uses a lightweight, high-strength, non-conductive material as its framework. The transmitting coil is fixed to the outermost ring-shaped support. Three mutually perpendicular mounting planes are precisely machined in the central region of the probe to fix three square receiving coil frames, ensuring that their axes are orthogonal to each other.

[0032] like Figure 2 As shown, the transmitting coil 1 is designed as a circle to generate a relatively uniform primary field. The coil is made of 17 turns of enameled copper wire, with an inductance of approximately 397uH and a DC resistance of approximately 629mΩ. This low-resistance, moderate-inductance parameter design helps to obtain a higher transient transmit current peak at a given supply voltage and ensures that the transmit current can be quickly established and turned off, meeting the pulse edge requirements of transient electromagnetic methods for shallow, high-resolution detection. The transmitting coil is connected to the transmitting circuit via two wires, A+ and A-.

[0033] All three receiving coils are square, mechanically perpendicular to each other, forming a three-dimensional magnetic field measurement unit. Differentiated sizes are used for the three coils: the outer, large coil (26 cm side length, 25 turns, approximately 393 μH inductance) offers higher sensitivity to relatively slow-changing magnetic field gradients from deeper or larger targets, helping to extend detection depth. The middle, medium-sized coil (19 cm side length, 27 turns, approximately 403 μH inductance) strikes a balance between detection sensitivity and spatial resolution, suitable for detecting most medium-sized anomalies. The inner, small coil (17 cm side length, 30 turns, approximately 394 μH inductance) is more sensitive to localized, drastic magnetic field gradient changes caused by shallow or small-scale targets, effectively improving the probe's near-surface resolution and target location accuracy. All coils are structurally fixed to ensure orthogonality. The signal from each coil is output via independent cables (Bi+, Bi-) and connected to subsequent receiving and processing circuitry.

[0034] like Figure 3 As shown, the transmitting circuit includes a high-speed optocoupler isolator Q16. The first pin of the high-speed optocoupler isolator Q16 is grounded through resistor R97 and receives MCU signals through resistor R95. The third and fourth pins are grounded, the sixth pin is electrically connected to the 12V voltage input terminal, the fifth pin is grounded through resistor R13, and is electrically connected to the gate of the field-effect transistor through resistor R19, resistor R26, and resistor R26 is grounded. The drain of the field-effect transistor is electrically connected to the 12V voltage input terminal through capacitor C25. The two wires A+ and A- of the transmitting coil are connected to the two sides of capacitor C25, respectively. The source of the field-effect transistor is grounded through electrolytic capacitor C66 and resistor R98.

[0035] The two sides of capacitor C25 are electrically connected to the two wires A+ and A- of the transmitting coil through electrolytic capacitors C15 and C36, respectively. The two sides of electrolytic capacitor C66 are electrically connected to the 12V voltage input terminal through resistor R25 and electrolytic capacitor C67, respectively. The ground terminal of resistor R98 is electrically connected to the 12V voltage input terminal through diode D6.

[0036] The transmitting circuit is equipped with a detection resistor R98 to monitor the current status and immediately stop transmitting if an abnormality is detected.

[0037] The MCU generates a PWM sequence with a 1kHz frequency and a 10% duty cycle as the transmit control signal. This transmit control signal is connected to a high-speed optocoupler Q16 to achieve electrical isolation between the control and power drive terminals, enhancing system anti-interference capabilities and protecting the MCU. The output of the high-speed optocoupler Q16 drives the gate of an N-channel power MOSFET. The drain of the MOSFET is connected to the A+ terminal of the transmit coil via a low-impedance wire, and the A- terminal of the transmit coil is connected to a high level. A low-resistance sampling and sensing resistor R98 is connected in series between the source and power ground of the MOSFET to monitor the transmit current. The MOSFET's rapid turn-on and turn-off control the current flow in the transmit coil. The transmit coil is equivalent to an inductor and resistor in series. To discharge the high-voltage back EMF generated by the transmit coil inductance at the moment of turn-off, a fast recovery Zener diode and a power resistor are connected in reverse parallel across the transmit coil to limit voltage spikes and accelerate magnetic field decay.

[0038] The three receiving and processing circuits have the same circuit structure, each including a first-stage amplification and filtering circuit, a second-stage controllable differential pair amplification circuit, and a third-stage time-windowing and integration amplification circuit. Each of the three receiving and processing circuits is responsible for low-noise amplification, filtering, and conditioning of the weak voltage signals induced by the three orthogonal receiving coils, in order to suppress common-mode interference and inter-channel crosstalk to the greatest extent possible.

[0039] like Figure 4 As shown, the first-stage amplification and filtering circuit includes three operational amplifiers U7, U8A, and U8B. The inverting input of operational amplifier U7 is electrically connected to one wire Bi+ of the receiving coil through an electrolytic capacitor C35. The non-inverting input of operational amplifier U7 is grounded through a diode and through a resistor and an electrolytic capacitor C64. The other wire Bi- of the receiving coil is electrically connected to the ground terminal of the electrolytic capacitor C64. The output of operational amplifier U7 is electrically connected to the inverting input of operational amplifier U8A through a resistor R14 and a capacitor C37. The output of operational amplifier U7 is grounded through a capacitor C54. A capacitor C14 and a capacitor C54 are connected in parallel between the inverting input and output of operational amplifier U7. Resistor R10 connects to ground the non-inverting input of operational amplifier U8A. The output of operational amplifier U8A is electrically connected to the inverting input of operational amplifier U8B through resistors R87 and R91. Capacitor C106 and resistor R96 are connected in parallel between the inverting input and output of operational amplifier U8A. The non-inverting input of operational amplifier U8B is grounded. The output of operational amplifier U8B outputs signal S123 to the two-stage controllable differential pair amplifier circuit through resistor R90 and capacitor C115. The output and inverting input of operational amplifier U8B are electrically connected through capacitor C107. The output of operational amplifier U8B is grounded through resistor R99 and capacitor C111.

[0040] After a field shutdown, the three receiving coils synchronously sense and output voltage signals proportional to the rate of change of their respective axial magnetic fields. These voltage signals are attached to the trailing signal, and operational amplifier U7 filters out the valid information. Operational amplifier U7 is used for signal conditioning, amplifying weak signals and performing second-order filtering for noise reduction. Bi+ and Bi- are connected to the input terminals of operational amplifier U7, amplified by a deep negative feedback amplifier circuit composed of resistor R10, and then subjected to noise reduction processing by a two-stage low-pass filter circuit.

[0041] like Figure 5 As shown, the second-stage controllable differential pair amplifier circuit includes a common-emitter differential pair amplifier circuit composed of transistors Q6 and Q7, a current sink circuit composed of transistors Q3 and Q8 and operational amplifier U9, an adjustable gain circuit composed of operational amplifiers U11A and U11B and transistor Q10, a signal buffer U14, a digital-to-analog converter U15, and a dual-channel analog switch U10. The MCU performs digital-to-analog conversion through the digital-to-analog converter U15, controls the output level to adjust the amplification factor of this stage circuit, and outputs signal S4 to the third-stage time window segmentation and integration amplifier circuit.

[0042] The current sink circuit is specifically designed to address the problem of insufficient low-level output capability of operational amplifiers. It enhances both the output swing and the load-carrying capacity, while stabilizing the DC bias through a feedback loop.

[0043] The function of signal buffer U14 is to provide impedance isolation and signal drive enhancement, which protects the preceding circuit and ensures that the following stage can receive signals stably and accurately.

[0044] The function of the dual-channel analog switch U10 is to control the selection and switching of control signals, so as to realize the multi-mode operation of the circuit.

[0045] like Figure 6 As shown, the three-stage time window segmentation and integration amplifier circuit includes an analog switch and three integration amplifier circuits. The input signal S4 is segmented into three observation signals S1, S2 and S3 with different time widths after passing through the analog switch. Each of the three observation signals is output to the MCU for processing after passing through an integration amplifier circuit.

[0046] like Figure 7 As shown, the core function of the power supply circuit is to convert the input electrical energy into a stable DC voltage required by the probe. The input voltage of the power supply circuit is 12V, which is first boosted to 14V, and then the LDO chip outputs 3.3V and ±5V voltages. The 3.3V voltage powers the MCU, and the ±5V voltage powers the operational amplifier and analog switches.

Claims

1. A three-component electromagnetic induction probe based on a separate transceiver unit, characterized in that: It includes a circular transmitting coil and three square receiving coils that are orthogonal to each other in pairs. The transmitting coil is located at the outermost edge of the probe, and the three receiving coils are inside the transmitting coil and are centrally symmetrical about the center of the transmitting coil. The transmitting coil is electrically connected to the transmitting circuit, and the three receiving coils are electrically connected to three receiving processing circuits respectively. The transmitting circuit and the three receiving processing circuits are all electrically connected to the MCU. The probe is powered by a power supply circuit.

2. The three-component electromagnetic induction probe based on a separate transceiver unit according to claim 1, characterized in that: The transmitting coil is made of copper enameled wire with 16-20 turns, an inductance of 450μH ± 100μH, and a DC resistance of 670mΩ ± 70mΩ. The transmitting coil is connected to the transmitting circuit through two wires.

3. The three-component electromagnetic induction probe based on a separate transceiver unit according to claim 1, characterized in that: The transmitting circuit includes a high-speed optocoupler isolator Q16. The first pin of the high-speed optocoupler isolator Q16 is grounded through resistor R97 and receives MCU signals through resistor R95. The third and fourth pins are grounded, the sixth pin is electrically connected to the 12V voltage input terminal, the fifth pin is grounded through resistor R13, and is electrically connected to the gate of the field-effect transistor through resistor R19, resistor R26, and resistor R26 is grounded. The drain of the field-effect transistor is electrically connected to the 12V voltage input terminal through capacitor C25. The two wires of the transmitting coil are connected to the two sides of capacitor C25 respectively. The source of the field-effect transistor is grounded through electrolytic capacitor C66 and resistor R98.

4. The three-component electromagnetic induction probe based on a separate transceiver unit according to claim 3, characterized in that: The two sides of capacitor C25 are electrically connected to the two wires of the transmitting coil through electrolytic capacitors C15 and C36, respectively. The two sides of electrolytic capacitor C66 are electrically connected to the 12V voltage input terminal through resistor R25 and electrolytic capacitor C67, respectively. The ground terminal of resistor R98 is electrically connected to the 12V voltage input terminal through diode D6.

5. The three-component electromagnetic induction probe based on a separate transceiver unit according to claim 1, characterized in that: The receiving coils are made of copper enameled wire. The outer first receiving coil has a side length of 26cm, 25 turns, an inductance of 393μH ± 20μH, and a DC resistance of 550mΩ ± 50mΩ. The middle second receiving coil has a side length of 19cm, 27 turns, an inductance of 403μH ± 20μH, and a DC resistance of 536mΩ ± 50mΩ. The inner third receiving coil has a side length of 17cm, 30 turns, an inductance of 394μH ± 20μH, and a DC resistance of 510mΩ ± 50mΩ. The receiving coils are connected to the receiving processing circuit through two wires.

6. The three-component electromagnetic induction probe based on a separate transceiver unit according to claim 1, characterized in that: The three receiving and processing circuits have the same circuit structure, each including a first-stage amplification and filtering circuit, a second-stage controllable differential pair amplification circuit, and a third-stage time window segmentation and integration amplification circuit.

7. The three-component electromagnetic induction probe based on a separate transceiver unit according to claim 6, characterized in that: The first-stage amplification and filtering circuit includes three operational amplifiers, U7, U8A, and U8B. The inverting input of operational amplifier U7 is electrically connected to one wire of the receiving coil via an electrolytic capacitor C35. The non-inverting input of operational amplifier U7 is grounded via a diode and also via a resistor and an electrolytic capacitor C64. The other wire of the receiving coil is electrically connected to the ground terminal of electrolytic capacitor C64. The output of operational amplifier U7 is electrically connected to the inverting input of operational amplifier U8A via a resistor R14 and a capacitor C37. The output of operational amplifier U7 is grounded via a capacitor C54. A capacitor C14 and a resistor R1 are connected in parallel between the inverting input and output of operational amplifier U7.

0. The non-inverting input of operational amplifier U8A is grounded. The output of operational amplifier U8A is electrically connected to the inverting input of operational amplifier U8B through resistors R87 and R91. A capacitor C106 and a resistor R96 are connected in parallel between the inverting input and the output of operational amplifier U8A. The non-inverting input of operational amplifier U8B is grounded. The output of operational amplifier U8B outputs signal S123 to the two-stage controllable differential pair amplifier circuit through resistor R90 and capacitor C115. The output and inverting input of operational amplifier U8B are electrically connected through capacitor C107. The output of operational amplifier U8B is grounded through resistor R99 and capacitor C111.

8. The three-component electromagnetic induction probe based on a separate transceiver unit according to claim 6, characterized in that: The two-stage controllable differential pair amplifier circuit includes a common-emitter differential pair amplifier circuit composed of transistors Q6 and Q7, a current sink circuit composed of transistors Q3 and Q8 and operational amplifier U9, an adjustable gain circuit composed of operational amplifiers U11A and U11B and transistor Q10, a signal buffer U14, a digital-to-analog converter U15, and a dual-channel analog switch U10. The MCU performs digital-to-analog conversion through U15 and outputs signal S4 to the three-stage time window segmentation and integration amplifier circuit.

9. The three-component electromagnetic induction probe based on a separate transceiver unit according to claim 6, characterized in that: The three-stage time window segmentation and integration amplifier circuit includes an analog switch and three integration amplifier circuits. The input signal S4 is segmented into three observation signals S1, S2 and S3 with different time widths after passing through the analog switch. Each of the three observation signals is output to the MCU after passing through an integration amplifier circuit.

10. The three-component electromagnetic induction probe based on a separate transceiver unit according to claim 1, characterized in that: The power supply circuit has an input voltage of 12V, which is first boosted to 14V, and then the LDO chip outputs 3.3V and ±5V voltages.

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