Dynamic beam MIMO array near-field electromagnetic imaging system and method for orthopedic surgery

Abstract

The invention discloses a dynamic beam MIMO array near-field electromagnetic imaging system and method for orthopedic surgery. The dynamic beam MIMO array near-field electromagnetic imaging system comprises a dynamic beam pairing MIMO array module, a power module, an FPGA digital signal processing module, a transceiver module and a display terminal which are integrated on a product host. The output end of the power supply module is electrically connected with the FPGA digital signal processing module and the transceiver module and provides stable power supply. The dynamic beam pairing MIMO array module, the transceiver module, the FPGA digital signal processing module and the display terminal are in signal connection in sequence. The invention relates to the technical field of biomedical electromagnetic imaging. According to the invention, the problems of failure of a near-field algorithm, difficulty in consideration of high resolution and high frame rate, and complexity and inconvenience of a system in a traditional electromagnetic imaging technology are solved.

Description

Technical Field

[0001] This invention relates to the field of biomedical electromagnetic imaging technology, and in particular to a dynamic beam MIMO array near-field electromagnetic imaging system and method for orthopedic surgery. Background Technology

[0002] The precision and safety of orthopedic surgery rely heavily on real-time visualization of deep bone structures, soft tissue boundaries, and the location of implants such as plates and screws within the surgical field. Currently, intraoperative imaging in clinical practice primarily relies on C-arm X-ray machines, but these have inherent and unavoidable drawbacks: they not only generate ionizing radiation, posing potential health risks to patients and medical staff, but also only provide two-dimensional imaging results, failing to clearly present soft tissue information. Furthermore, the equipment is bulky, inconvenient to move, and difficult to adapt to the flexible demands of surgical scenarios.

[0003] Electromagnetic imaging technology, as an ideal alternative to non-ionizing radiation, has attracted much attention in the biomedical field. However, it still faces three key challenges in orthopedic surgery: First, the surgical area is typically 10-100cm from the body surface, in the near-field region of the antenna. Traditional far-field imaging algorithms are completely ineffective due to wavefront bending effects, failing to achieve accurate imaging. Second, millimeter-level imaging resolution relies on large aperture or broadband signals, while the signal processing speed of traditional mechanical scanning or simultaneous full-array operation is slow, making it difficult to meet the dynamic monitoring needs of respiratory movement and instrument movement during surgery. Third, traditional multi-channel radio frequency systems are complex and bulky, making them difficult to integrate into portable surgical devices and unsuitable for flexible deployment around the operating table. Therefore, there is an urgent clinical need for an electromagnetic imaging solution that combines high resolution, high frame rate, portability, and near-field optimization to overcome existing technological bottlenecks and improve the accuracy and safety of orthopedic surgery. Summary of the Invention

[0004] To address the problems of near-field algorithm failure, difficulty in achieving both high resolution and high frame rate, and system complexity and inconvenience in traditional electromagnetic imaging technology, the present invention aims to provide a dynamic beam MIMO array near-field electromagnetic imaging system and method for orthopedic surgery.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a portable real-time electromagnetic imaging system for local areas of orthopedic surgical patients, comprising a dynamic beam-pairing MIMO array module, a power supply module, an FPGA digital signal processing module, a transceiver module, and a display terminal integrated into the main unit of the product; the output terminal of the power supply module is electrically connected to the FPGA digital signal processing module and the transceiver module respectively and provides stable power supply; the dynamic beam-pairing MIMO array module, the transceiver module, the FPGA digital signal processing module, and the display terminal are sequentially connected by signals; the dynamic beam-pairing MIMO array module performs near-field dynamic beam pairing under the control of the transceiver module, transmits electromagnetic detection signals to the local area of ​​the orthopedic surgical patient and receives reflected echo signals, the echo signals are conditioned by the transceiver module and transmitted to the FPGA digital signal processing module, and after digital processing and tomographic imaging calculation, outputs point cloud data with depth information, and the display terminal receives the data and completes near-field real-time electromagnetic tomographic imaging and visualization output.

[0006] Preferably, the dynamic beam-paired MIMO array module uses ceramic patch elements, integrating 64-128 transmitters and 64-128 receivers, and forms 4096-16384 virtual subarrays through adaptive dynamic beam-pairing logic. The distance between the transmitter and receiver is 2 times and 0.5 times the wavelength of the corresponding frequency band, respectively, to achieve a low profile structure and a 120dB receiving dynamic range.

[0007] Preferably, the dynamic beam-paired MIMO array module operates in the frequency band of 5.2G-8G, has a frequency conversion bandwidth of 2.8G, and a near-field detection distance of 0.1m-0.5m, which is suitable for the high-precision near-field detection requirements of local areas in orthopedic surgery.

[0008] Preferably, the transceiver module adopts the FMCW frequency modulation continuous wave system, and has a built-in digital beamforming unit and quadrature modulation I / Q circuit. After frequency conversion, filtering and amplification of the echo signal, it outputs a standardized I / Q dual-channel signal to avoid detection zero-point error.

[0009] Preferably, the transceiver module is further provided with an adjustable DC bias circuit and a VGA adjustable gain amplifier. The amplitude of the DC bias signal is controlled within the rated voltage range of the FPGA interface board, and the gain can be dynamically adjusted according to the detection depth.

[0010] Preferably, the FPGA digital signal processing module adopts an integrated interface board, is configured with two 16-bit ADC converters, a sampling rate of 250Msps, and has built-in FIR filter IP core, two-dimensional FFT IP core and tomographic imaging dedicated computing unit to complete signal digitization and hierarchical reconstruction data processing.

[0011] Preferably, the FPGA interface board integrates a memory, an Ethernet module, and a USB 3.0 module. The memory is used to store raw point cloud data and tomographic imaging results, the Ethernet module supports remote data sharing, and the USB 3.0 module enables real-time transmission of point cloud data.

[0012] Preferably, the display terminal is a mobile phone or computer, which has a built-in FMCW radar frequency wavenumber migration tomography algorithm and VTK3D rendering software package, and can realize multi-depth tomographic image generation, three-dimensional reconstruction, feature extraction and registration functions.

[0013] Preferably, the beam pairing logic of the dynamic beam pairing MIMO array module is controlled in real time by the FPGA digital signal processing module, which adaptively adjusts the pairing combination of the transmitter and receiver according to the echo signal strength to improve the signal gain and imaging resolution of the target area.

[0014] A near-field electromagnetic imaging method using a dynamic beam MIMO array for orthopedic surgery includes the following steps: S1, the power module starts up, providing stable power to the FPGA digital signal processing module and transceiver module, and each module completes initialization; S2, the FPGA digital signal processing module sends control commands to the transceiver module, driving the dynamic beam-pairing MIMO array module to perform adaptive dynamic beam-pairing and transmit 5.2G-8G frequency band electromagnetic detection signals to the near-field area of ​​the patient's surgical site; S3, the dynamic beam-paired MIMO array module receives the echo signal reflected by the patient tissue and transmits it to the transceiver module; S4, the transceiver module performs frequency conversion, filtering, amplification, and I / Q quadrature modulation on the echo signal, and outputs a standardized analog signal; S5, the FPGA digital signal processing module converts analog signals into digital signals through a 16-bit ADC converter, and generates point cloud data with depth information through FIR filtering, two-dimensional FFT operation and tomographic imaging layer reconstruction processing, and stores it synchronously. S6, the display terminal receives point cloud data through the USB3.0 interface, generates multi-depth tomographic images using the FK offset algorithm, and outputs real-time electromagnetic tomography results to the surgeon after 3D rendering, feature extraction and registration by the VTK software package.

[0015] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: 1. This invention employs a dynamic grouped beam pairing scanning mechanism, combined with digital beamforming technology. By dynamically selecting the optimal transmitting and receiving antenna pairs and dividing them into 6-7 groups for time-division multiplexing, more than 40 echo signal channels are equivalently expanded from 32 physical antenna elements through virtual array synthesis technology, significantly improving the spatial resolution of near-field imaging. Coupled with 8192-point high-precision sampling and a near-field dedicated fast reconstruction algorithm, a refresh rate of ≤0.1 seconds per frame image is achieved, perfectly solving the core contradiction of difficulty in balancing resolution and real-time performance in near-field imaging, and accurately capturing dynamic structural changes in the surgical area.

[0016] 2. This invention employs a compact MIMO array antenna unit with 32 antenna elements arranged in 4 rows and 8 columns, resulting in an overall physical size of only 10cm × 12cm. Combined with a streamlined time-division duplex RF channel and modular integrated design, the entire system can be housed in a portable chassis, eliminating the need for large fixed equipment. It can be flexibly deployed around the operating table and even adaptable to handheld operation requirements, completely solving the problems of large size and inconvenience of traditional multi-channel electromagnetic imaging systems.

[0017] 3. The present invention operates in a wide frequency band of 3-10 GHz, which can effectively improve the detection sensitivity of bones, soft tissues and implants; the transmitter uses DBF technology to electronically scan within the horizontal angle [-5°, 5°] and pitch angle [-5°, 5°], enhancing the irradiation energy of the target area and suppressing sidelobe interference; the near-field dedicated imaging algorithm is designed based on the fusion of two-dimensional Fourier transform and CT principle, and specifically corrects the near-field wavefront bending effect. Compared with traditional algorithms, the reconstructed image has less geometric distortion and higher contrast, and can clearly present the bone boundary, soft tissue layers and implant position relationship, providing a reliable reference for precise surgical operation.

[0018] 4. This invention employs electromagnetic detection technology, which poses no ionizing radiation hazard and is suitable for long-term real-time monitoring during surgery, avoiding the radiation risks associated with C-arm X-ray machines. The system parameters are specifically optimized for orthopedic surgical scenarios, with an imaging distance covering a near-field range of 10-100cm, making it adaptable to various orthopedic surgical types such as fracture reduction, joint replacement, and implant fixation. It also supports fusion verification with intraoperative C-arm X-ray images, is compatible with existing hospital diagnostic and treatment procedures, lowers the threshold for clinical promotion, and combines safety and practicality. Attached Figure Description

[0019] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments: Figure 1 This is a schematic diagram of the layout and numbering of the 4×8 MIMO antenna array of the present invention; Figure 2 This is a complete flowchart of the imaging method of the present invention; Figure 3This is a schematic diagram of grayscale imaging for dynamic grouped beam pairing scanning according to the present invention; Figure 4 This is a schematic diagram of the FMCW spectrum of the present invention. Detailed Implementation

[0020] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

[0021] Please see Figures 1 to 4 It should be understood that the structures, proportions, sizes, etc., illustrated in the accompanying drawings are merely for illustrative purposes to aid those skilled in the art and to facilitate understanding and reading. They are not intended to limit the scope of the invention and therefore have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effectiveness and purpose of the invention, should still fall within the scope of the technical content disclosed in this invention. Furthermore, the terms such as "upper," "lower," "left," "right," "middle," and "one" used in this specification are merely for clarity and not intended to limit the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention's implementation.

[0022] Example 1: A dynamic beamforming MIMO array near-field electromagnetic imaging system for orthopedic surgery includes a compact MIMO area array antenna unit, an intelligent waveform control and DBF unit, a broadband FMCW RF transceiver unit, a high-speed data acquisition and processing unit, and a near-field dedicated imaging algorithm unit. All modules are integrated into a portable chassis and work collaboratively with a display terminal. The overall structure is compact, meeting the flexible deployment requirements of operating rooms. A schematic diagram of its MIMO antenna array layout and numbering is shown below. Figure 1 As shown.

[0023] The compact MIMO area array antenna unit adopts a planar array design, consisting of 32 antenna elements in 4 rows × 8 columns, with an overall physical size of 10cm × 12cm and an operating frequency band of 3-10GHz. Each antenna element is assigned an independent number (1-32) and integrates an RF switch, supporting time-division duplex (TDD) operation mode, enabling rapid switching between transmit and receive functions to meet the requirements of group time-division scanning. The core function of this unit is to directionally transmit electromagnetic detection signals and capture echo signals reflected from the surgical field area of ​​the patient in real time.

[0024] The intelligent waveform control and DBF unit, as the core scheduling module of the system, is configured as follows: Dynamic antenna pair selection: Based on the pre-set imaging area range before surgery, such as a 15cm×15cm×10cm cube area and millimeter-level resolution requirements in knee replacement surgery, the optimal transmit-receive antenna pair combination is dynamically calculated and screened based on the near-field beam propagation model. For example, antenna pairs (1,3), (2,6), (5,15), etc. are used for focusing at specific depths to ensure full coverage and high-resolution imaging of the target area.

[0025] Group scanning mechanism: The selected multiple antenna pairs are divided into 6 to 7 working groups. Antenna pairs in the same group have similar beam directions or correspond to the same imaging sub-region. Signal transmission and reception are completed in time-division mode through TDD mode to avoid inter-channel interference.

[0026] Dynamic beamforming: At the transmitting end, precise phase compensation is applied to the transmitting antennas in each group through digital phase weighting technology, so that the transmitting beam can be electronically scanned within the horizontal angle [-5°, 5°] and the elevation angle [-5°, 5°], which enhances the illumination energy of the target area, while suppressing sidelobe interference and improving the signal-to-noise ratio of the echo signal.

[0027] The core function of the broadband FMCW RF transceiver unit is to generate a 3-10GHz linear frequency modulated continuous wave signal. Through intelligent waveform control and DBF unit scheduling, the signal is precisely distributed to the selected transmitting antenna. The receiving link includes a down-conversion module, which performs frequency conversion processing on the echo signal received by the antenna and outputs a stable intermediate frequency analog signal, providing a foundation for subsequent data acquisition. Its FMCW spectrum diagram is shown below. Figure 4 As shown.

[0028] The high-speed data acquisition and processing unit employs a high-precision analog-to-digital converter module to perform 8192 real-valued samplings of the intermediate-frequency analog signal, ensuring high-fidelity acquisition of the echo signal. This unit incorporates a synthetic aperture processing algorithm module, capable of coherently synthesizing and phase-calibrating 6-7 groups of sampled data, virtually generating echo signals equivalent to more than 40 physical channels, significantly expanding the effective aperture of the array and improving spatial resolution. Simultaneously, this unit integrates a data buffer module to temporarily store raw sampled data and processed intermediate data, ensuring the continuity of data transmission.

[0029] Near-field dedicated imaging algorithm unit: Employing a hybrid algorithm based on two-dimensional Fourier transform (FFT2) and computed tomography (CT) principles, specifically optimized for near-field distances of 10-100cm. The algorithm flow includes: performing range-direction FFT processing on the virtual array data to obtain the target range profile; arranging the data from the same range gate in each virtual channel according to spatial position to form a two-dimensional spatial spectrum; applying near-field corrected inverse Radon transform or back projection algorithm to the two-dimensional spatial spectrum to reconstruct a two-dimensional tomographic image at a specific depth; generating multi-slice tomographic images by switching range gates, and then synthesizing a three-dimensional imaging result. A schematic diagram of the algorithm flow is shown below. Figure 2 As shown.

[0030] The display terminal uses a medical monitor, computer, or dedicated mobile terminal, connected to a high-speed data acquisition and processing unit via a high-speed data interface. It receives tomographic image data and 3D reconstruction results in real time, refreshing the display at a rate of ≤0.1 seconds / frame. It also supports image scaling, rotation, and feature annotation, providing surgeons with intuitive real-time visual references. A schematic diagram of its grayscale imaging effect is shown below. Figure 3 As shown.

[0031] Example 2, a near-field electromagnetic imaging method using a dynamic beam MIMO array for orthopedic surgery, specifically includes the following steps: Step 1: Imaging Planning and Beam Pairing Pre-calculation: Based on the surgical navigation information or the pre-operative planned region of interest, such as a 15cm×15cm×10cm space centered on the femoral condyle in knee replacement surgery, the system control unit calls the near-field beam propagation model to calculate the list of transmit-receive antenna pair combinations required to achieve optimal coverage and resolution in this area. This list is divided into 6-7 working groups, and the corresponding DBF phase weight is calculated for each group to complete the initialization of scanning parameters.

[0032] Step 2: Dynamic Grouped Beam Scanning and Data Acquisition: The system operates sequentially according to a preset grouping order. For the current group: ① Load the corresponding DBF phase weight to form a directional beam using the selected transmitting antenna; ② Transmit a 3-10 GHz linear frequency modulated continuous wave signal through the broadband FMCW RF transceiver unit; ③ Switch to receiving mode, and receive the scattered echo reflected from the target area by the paired receiving antenna; ④ The RF transceiver unit performs down-conversion processing on the echo signal and outputs an intermediate frequency analog signal; ⑤ The high-speed data acquisition unit performs 8192 real-valued samples on the intermediate frequency signal and stores them in the buffer module; ⑥ Repeat the above operations until all groups are scanned, completing the data acquisition for one frame of imaging.

[0033] Step 3: Virtual Array Synthesis and Data Preprocessing: The high-speed data acquisition and processing unit calls the coherent synthesis algorithm to perform time synchronization and phase calibration on the original sampled data of all groups based on the geometric position, transmitted waveform parameters and sampling timestamps of each group antenna pair. Through synthetic aperture processing, a holographic dataset equivalent to more than 40 virtual antenna channels is generated, and noise filtering and signal enhancement preprocessing are completed at the same time.

[0034] Step 4: Near-field fast tomographic image reconstruction: ① Range processing: Perform FFT operation on the 8192-point sampling sequence of each virtual channel to obtain the range profile of the target area; ② Angular synthesis: Arrange the data of all virtual channels at the same range gate according to their spatial positions to construct a two-dimensional spatial spectrum; ③ Fault reconstruction: Apply the inverse Radon transform or back projection algorithm after near-field propagation path curvature correction to the two-dimensional spatial spectrum to reconstruct a two-dimensional tomographic image at a specific depth in the observation plane; ④ Three-dimensional synthesis: By changing the range gate parameters, repeat the above steps to obtain a series of parallel tomographic images, and generate a three-dimensional reconstructed image through stitching and fusion processing.

[0035] Step 5: Real-time display and feedback: The display terminal receives the two-dimensional tomographic image sequence and the three-dimensional reconstruction results, and refreshes the display at a rate of ≤0.1 seconds / frame. Doctors can view the real-time status of bones, soft tissues and implants in the surgical field through the terminal. Combined with image feature extraction and registration functions, they can dynamically adjust the surgical plan and complete precise operations. At the same time, it supports real-time storage and export of imaging data, which is convenient for postoperative review and case analysis.

[0036] Example 3, in actual knee replacement surgery: System deployment: The imaging probe, which integrates a compact MIMO array antenna unit, is encapsulated in a sterile sheath and fixed above the operating table. The distance between the probe and the affected knee is adjusted to 30cm to ensure that the imaging area completely covers the surgical field.

[0037] Parameter settings: Input the imaging area parameters through the system control software and set it as a 15cm×15cm×10cm (length×width×depth) cube centered on the femoral condyle. The system automatically calculates the optimal transmit-receive antenna pair combination and grouping scheme (6 groups) and loads the corresponding DBF phase weights.

[0038] Real-time scanning: Start the system and perform dynamic grouped beam scanning, data acquisition and image reconstruction according to steps 2-4 in Example 3. Each frame takes about 0.08 seconds to image, which meets the needs of real-time surgical monitoring.

[0039] Image-guided: The display terminal presents real-time two-dimensional tomographic images and three-dimensional renderings of the distal femur, tibial plateau, and surrounding cartilage and ligaments. Doctors can use the images to accurately assess the osteotomy angle, prosthesis fit, and soft tissue balance, and dynamically adjust the surgical procedure.

[0040] Intraoperative verification: The imaging results of this system are fused with intraoperative C-arm X-ray images to verify the imaging accuracy. The surgical process is continuously monitored under radiation-free conditions until the prosthesis is implanted in place and its position is confirmed to be accurate.

[0041] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A dynamic beam MIMO array near-field electromagnetic imaging system for orthopedic surgery, characterized in that, The device includes a dynamic beam-pairing MIMO array module, a power supply module, an FPGA digital signal processing module, a transceiver module, and a display terminal, all integrated into the main unit of the product. The output of the power supply module is electrically connected to the FPGA digital signal processing module and the transceiver module, respectively, and provides stable power. The dynamic beam-pairing MIMO array module, transceiver module, FPGA digital signal processing module, and display terminal are sequentially connected by signals. The dynamic beam-pairing MIMO array module performs near-field dynamic beam pairing under the control of the transceiver module. It transmits electromagnetic detection signals to the local area of ​​the patient undergoing orthopedic surgery and receives reflected echo signals. The echo signals are conditioned by the transceiver module and transmitted to the FPGA digital signal processing module. After digital processing and tomographic imaging calculation, it outputs point cloud data with depth information. The display terminal receives the data and completes near-field real-time electromagnetic tomography imaging and visualization output.

2. The dynamic beam MIMO array near-field electromagnetic imaging system for orthopedic surgery according to claim 1, characterized in that: The dynamic beam-paired MIMO array module uses ceramic patch elements to integrate 64-128 transmitters and 64-128 receivers. Through adaptive dynamic beam-pairing logic, it forms 4096-16384 virtual subarrays. The distance between the transmitter and receiver is 2 times and 0.5 times the wavelength of the corresponding frequency band, respectively, to achieve a low profile structure and a 120dB dynamic range.

3. The dynamic beam MIMO array near-field electromagnetic imaging system for orthopedic surgery according to claim 1, characterized in that: The dynamic beam-paired MIMO array module operates in the 5.2G-8G frequency band, has a frequency conversion bandwidth of 2.8G, and a near-field detection distance of 0.1m-0.5m, which is suitable for the high-precision near-field detection requirements of local areas in orthopedic surgery.

4. The dynamic beam MIMO array near-field electromagnetic imaging system for orthopedic surgery according to claim 1, characterized in that: The transceiver module adopts the FMCW frequency modulation continuous wave system, and has a built-in digital beamforming unit and quadrature modulation I / Q circuit. After frequency conversion, filtering and amplification of the echo signal, it outputs a standardized I / Q dual-channel signal to avoid detection zero-point error.

5. The dynamic beam MIMO array near-field electromagnetic imaging system for orthopedic surgery according to claim 1, characterized in that: The transceiver module is also equipped with an adjustable DC bias circuit and a VGA adjustable gain amplifier. The DC bias signal amplitude is controlled within the rated voltage range of the FPGA interface board, and the gain can be dynamically adjusted according to the detection depth.

6. The dynamic beam MIMO array near-field electromagnetic imaging system for orthopedic surgery according to claim 1, characterized in that: The FPGA digital signal processing module adopts an integrated interface board, is equipped with two 16-bit ADC converters, has a sampling rate of 250Msps, and has built-in FIR filter IP core, two-dimensional FFT IP core and tomographic imaging dedicated computing unit to complete signal digitization and hierarchical reconstruction data processing.

7. The dynamic beam MIMO array near-field electromagnetic imaging system for orthopedic surgery according to claim 1, characterized in that: The FPGA interface board integrates a memory, an Ethernet module, and a USB 3.0 module. The memory is used to store raw point cloud data and tomographic imaging results, the Ethernet module supports remote data sharing, and the USB 3.0 module enables real-time transmission of point cloud data.

8. The dynamic beam MIMO array near-field electromagnetic imaging system for orthopedic surgery according to claim 1, characterized in that: The display terminal is a mobile phone or computer, which has a built-in FMCW radar frequency wavenumber migration tomography algorithm and VTK3D rendering software package, and can realize multi-depth tomographic image generation, three-dimensional reconstruction, feature extraction and registration functions.

9. The dynamic beam MIMO array near-field electromagnetic imaging system for orthopedic surgery according to claim 1, characterized in that: The beam pairing logic of the dynamic beam-pairing MIMO array module is controlled in real time by the FPGA digital signal processing module. It adaptively adjusts the pairing combination of the transmitter and receiver according to the echo signal strength to improve the signal gain and imaging resolution of the target area.

10. A near-field electromagnetic imaging method using a dynamic beam MIMO array for orthopedic surgery, characterized in that, The orthopedic surgical dynamic beam MIMO array near-field electromagnetic imaging system according to any one of claims 1-9 is used. Includes the following steps: S1, the power module starts up, providing stable power to the FPGA digital signal processing module and transceiver module, and each module completes initialization; S2, the FPGA digital signal processing module sends control commands to the transceiver module, driving the dynamic beam-pairing MIMO array module to perform adaptive dynamic beam-pairing and transmit 5.2G-8G frequency band electromagnetic detection signals to the near-field area of ​​the patient's surgical site; S3, the dynamic beam-paired MIMO array module receives the echo signal reflected by the patient tissue and transmits it to the transceiver module; S4, the transceiver module performs frequency conversion, filtering, amplification, and I / Q quadrature modulation on the echo signal, and outputs a standardized analog signal; S5, the FPGA digital signal processing module converts analog signals into digital signals through a 16-bit ADC converter, and generates point cloud data with depth information through FIR filtering, two-dimensional FFT operation and tomographic imaging layer reconstruction processing, and stores it synchronously. S6, the display terminal receives point cloud data through the USB3.0 interface, generates multi-depth tomographic images using the FK offset algorithm, and outputs real-time electromagnetic tomography results to the surgeon after 3D rendering, feature extraction and registration by the VTK software package.

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