Weak magnetic field detection system and method

Abstract

The present invention provides a weak magnetic field detection system and method, wherein the system includes: a Hall sensor, which is used to detect the weak magnetic field at the position to be detected to generate and send a Hall signal; a magnetoresistive sensor, which is used to detect the weak magnetic field at the position to be detected to generate and send a magnetoresistive signal; a miniaturized superconducting quantum interference instrument, which is used to detect the weak magnetic field at the position to be detected to generate and send a superconducting quantum interference signal; a signal processing circuit, which at least includes: a fusion module, which is electrically connected to the Hall sensor, the magnetoresistive sensor, and the miniaturized superconducting quantum interference instrument, respectively, and is used to receive the Hall signal, the magnetoresistive signal, and the superconducting quantum interference signal, and fuse the received Hall signal, the magnetoresistive signal, and the superconducting quantum interference signal to obtain a multi-source fused magnetic field signal and send it; a signal analysis module, which is used to receive the multi-source fused magnetic field signal, and generate a magnetic field strength value representing the strength of the weak magnetic field at the position to be detected according to the received multi-source fused magnetic field signal.

Description

Technical Field

[0001] The present invention relates to the field of detection technology, and in particular to a weak magnetic field detection system and method. Background Art

[0002] In the wave of rapid development of modern science and technology, the application field of weak magnetic field detection technology is expanding day by day, and its influence has gradually penetrated from the profound halls of basic scientific research to the precision workshops of high-end industrial manufacturing and the delicate field of medical health diagnosis. The accurate detection of weak magnetic fields is not only a technical challenge, but also a key force to promote scientific and technological progress. It has irreplaceable and important value in understanding the microscopic world of magnetic field distribution, in-depth analysis of material properties, and exploration and research of biological magnetic fields.

[0003] However, the characteristics of weak magnetic fields make their detection particularly difficult. The strength of weak magnetic fields is usually between natus and gauss, and this weak magnetic field signal is often drowned out by environmental noise and other interference factors. Therefore, traditional magnetic field detection methods often seem powerless when faced with weak magnetic fields. For example, although fluxgate technology can measure weak magnetic fields to a certain extent, its lack of sensitivity and low measurement accuracy have greatly limited its practical application. In addition, factors such as environmental interference and temperature changes will also have a significant impact on the measurement results.

[0004] With the continuous development of science and technology, the requirements for weak magnetic field detection technology are getting higher and higher. First of all, sensitivity is one of the core indicators of weak magnetic field detection technology. Only with a high enough sensitivity can weak magnetic field signals be captured from complex environmental noise. Secondly, measurement accuracy is also crucial. In scientific research, industrial manufacturing and other fields, the precise grasp of magnetic field distribution often determines the depth and breadth of research. Finally, response speed is also a factor that cannot be ignored. In some application scenarios, such as medical and health diagnosis, it is necessary to quickly and accurately obtain magnetic field information in order to make timely judgments and decisions. Summary of the invention

[0005] In order to solve the above technical problems, the present application provides a weak magnetic field detection system and method to at least solve or alleviate the above problems in the prior art.

[0006] In order to achieve the above object, according to one aspect of the present application, a weak magnetic field detection system is provided, comprising:

[0007] A Hall sensor is used to detect a weak magnetic field at a position to be detected to generate and send a Hall signal;

[0008] A magnetoresistive sensor, used for detecting the weak magnetic field at the position to be detected to generate and send a magnetoresistive signal;

[0009] A miniaturized superconducting quantum interference device, used for detecting the weak magnetic field at the position to be detected to generate and send a superconducting quantum interference signal;

[0010] The signal processing circuit comprises at least:

[0011] A fusion module, electrically connected to the Hall sensor, the magnetoresistive sensor, and the miniaturized superconducting quantum interference device, respectively, for receiving the Hall signal, the magnetoresistive signal, and the superconducting quantum interference signal, and fusing the received Hall signal, the magnetoresistive signal, and the superconducting quantum interference signal to obtain a multi-source fused magnetic field signal and send it;

[0012] The signal analysis module is used to receive the multi-source fusion magnetic field signal and generate a magnetic field strength value representing the weak magnetic field strength at the position to be detected according to the received multi-source fusion magnetic field signal.

[0013] Optionally, the weak magnetic field detection system further includes: a temperature sensor for detecting the temperature at a position to be detected, so as to compensate the Hall signal, the magnetoresistance signal, and the superconducting quantum interference signal respectively according to the detected temperature.

[0014] Optionally, the Hall sensor also includes a first gain control circuit, which is used to determine the strength of the Hall signal, and adjust the gain of the Hall sensor to enhance the Hall signal according to the strength of the Hall signal so that the enhanced Hall signal reaches a set signal-to-noise ratio.

[0015] Optionally, the first gain control circuit includes a peak detection circuit, a comparator, and a gain control element, the peak detection circuit is used to detect the peak value of the Hall signal, the comparator is used to compare the peak value with the reference signal to generate a gain control signal, and the gain control element is used to adjust the gain of the Hall sensor according to the gain control signal.

[0016] Optionally, the peak detection circuit includes a four-quadrant multiplier and a low-pass filter, the four-quadrant multiplier is used to convert the Hall signal into a unidirectional pulsating signal, and the low-pass filter is used to smooth the unidirectional pulse signal to obtain a smoothed pulse signal to represent the peak value of the Hall signal.

[0017] Optionally, the gain control element includes: a coupling capacitor, a resistor voltage divider network, and a filter circuit, wherein the coupling capacitor is used to couple the gain control signal to the resistor voltage divider network, the resistor voltage divider network is used to perform voltage division processing on the gain control signal coupled thereto to obtain a voltage control signal, and the filter circuit filters the voltage control signal to adjust the gain of the Hall sensor.

[0018] Optionally, the magnetoresistive sensor has a plurality of set measuring axes, each measuring axis is configured with a symmetrical bridge composed of four magnetoresistive resistors, and each of the symmetrical bridges is connected to a preamplifier, so as to detect the weak magnetic field at the detected position in different directions along each measuring axis based on the stacked bridge to generate different magnetoresistive signal components, and the corresponding magnetoresistive signal components are amplified by the preamplifier to obtain amplified magnetoresistive signal components, and sent to the signal processing circuit to synthesize the different amplified magnetoresistive signal components to obtain the magnetoresistive signal and send it.

[0019] Optionally, the signal processing circuit includes: a low-noise amplifier, an analog-to-digital conversion circuit, a synchronous sampling circuit, and a microprocessor. The low-noise amplifier is used to filter the noise of the different amplified magnetoresistance signal components. The analog-to-digital conversion circuit is used to perform analog-to-digital conversion on the different amplified magnetoresistance signal components after the noise process to obtain corresponding digital components. The synchronous sampling circuit is used to synchronously sample the digital components corresponding to the different amplified magnetoresistance signal components to obtain sampling components. The microprocessor is used to perform vector synthesis on the synchronously sampled sampling components to obtain the magnetoresistance signal.

[0020] Optionally, the outside of the miniaturized superconducting quantum interference device is wrapped with multiple layers of superconducting material, and an insulating layer is arranged in the gap between two adjacent layers of superconducting material. Each layer of superconducting material is connected to a low-impedance path to dissipate the interference of external interfering electromagnetic fields on the weak magnetic field at the position to be detected. The material of the insulating layer is aluminum oxide or silicon dioxide, and the low-impedance path is a superconducting wire.

[0021] Optionally, the weak magnetic field detection system also includes a magnetoelectric sensor, which is used to capture electromagnetic noise signals inside and outside the miniaturized superconducting quantum interference device, and amplify the electromagnetic noise signal through a preamplifier to increase the signal-to-noise ratio to a preset signal-to-noise ratio threshold, so as to input it into a notch filter for noise band extraction, and enable a signal generator to generate an anti-phase neutralization signal according to the phase of the noise band to feedback and offset the electromagnetic noise signal to eliminate the electromagnetic noise signal.

[0022] Optionally, the signal processing circuit also includes: a polarization transmitter for generating rubidium atom polarization laser, and a xenon atom bias magnetic field for generating spinning xenon nuclei in a dark state, so as to spontaneously radiate the weak magnetic field at the position to be detected through coupling between the rubidium atom polarization laser and the spinning xenon nuclei in the dark state to amplify the weak magnetic field at the position to be detected, so that the Hall sensor, the magnetoresistive sensor, and the miniaturized superconducting quantum interference device respectively detect the amplified weak magnetic field at the position to be detected.

[0023] Optionally, the fusion module is specifically used to align the received Hall signal, the magnetoresistance signal, and the superconducting quantum interference signal in time and space to obtain calibrated magnetic field intensity components respectively, and perform Fourier transform on the calibrated magnetic field intensity components respectively to obtain a spectrum representation of each signal, perform multi-source fusion on the spectrum representation of each signal to obtain a multi-source fused spectrum representation, and convert the spectrum representation back to the time domain through inverse Fourier transform to obtain a multi-source fused magnetic field signal.

[0024] Optionally, the signal analysis module is used to receive the multi-source fusion magnetic field signal, and generate a magnetic field strength value representing the weak magnetic field strength at the position to be detected according to the received multi-source fusion magnetic field signal, including:

[0025] The multi-source fusion magnetic field signal is fitted with a pre-established Hall sensor physical model, a magnetoresistive sensor physical model, and a miniaturized superconducting quantum interference device physical model, respectively, to obtain a corresponding first magnetic field intensity estimate, a second magnetic field intensity estimate, and a third magnetic field intensity estimate; the first magnetic field intensity estimate, the second magnetic field intensity estimate, and the third magnetic field intensity estimate are Bayesian estimated to obtain a magnetic field intensity value characterizing the weak magnetic field intensity at the position to be detected.

[0026] Optionally, the signal analysis module performs least squares fitting on the multi-source fusion magnetic field signal and a pre-established Hall sensor model, a magnetoresistive sensor model, and a miniaturized superconducting quantum interference device model, respectively, to obtain corresponding first magnetic field intensity estimation value, second magnetic field intensity estimation value, and third magnetic field intensity estimation value; based on the expected performance description values ​​of the Hall sensor, the magnetoresistive sensor, and the miniaturized superconducting quantum interference device, the first magnetic field intensity estimation value, the second magnetic field intensity estimation value, and the third magnetic field intensity estimation value are Bayesian estimated to determine the likelihood functions of the first magnetic field intensity estimation value, the second magnetic field intensity estimation value, and the third magnetic field intensity estimation value relative to the multi-source fusion magnetic field signal, respectively, so as to calculate the magnetic field intensity value characterizing the weak magnetic field intensity at the position to be detected based on the likelihood function and the joint probability distribution between the first magnetic field intensity estimation value, the second magnetic field intensity estimation value, and the third magnetic field intensity estimation value.

[0027] A weak magnetic field detection method, comprising:

[0028] The Hall sensor detects the weak magnetic field at the position to be detected to generate and send a Hall signal;

[0029] The magnetoresistive sensor detects the weak magnetic field at the position to be detected to generate a magnetoresistive signal and sends it;

[0030] The miniaturized superconducting quantum interference device detects the weak magnetic field at the position to be detected to generate a superconducting quantum interference signal and sends it;

[0031] The fusion module in the signal processing circuit is electrically connected to the Hall sensor, the magnetoresistive sensor, and the miniaturized superconducting quantum interference device, respectively, and is used to receive the Hall signal, the magnetoresistive signal, and the superconducting quantum interference signal, and fuse the received Hall signal, the magnetoresistive signal, and the superconducting quantum interference signal to obtain a multi-source fused magnetic field signal and send it;

[0032] The signal analysis module in the signal processing circuit receives the multi-source fusion magnetic field signal, and generates a magnetic field strength value representing the weak magnetic field strength at the position to be detected according to the received multi-source fusion magnetic field signal.

[0033] The present invention provides a weak magnetic field detection system, wherein a Hall sensor is used to detect the weak magnetic field at a position to be detected to generate and send a Hall signal; a magnetoresistive sensor is used to detect the weak magnetic field at the position to be detected to generate and send a magnetoresistive signal; a miniaturized superconducting quantum interference instrument is used to detect the weak magnetic field at the position to be detected to generate and send a superconducting quantum interference signal; a signal processing circuit at least includes: a fusion module, which is electrically connected to the Hall sensor, the magnetoresistive sensor, and the miniaturized superconducting quantum interference instrument, respectively, and is used to receive the Hall signal, the magnetoresistive signal, and the superconducting quantum interference signal, and fuse the received Hall signal, the magnetoresistive signal, and the superconducting quantum interference signal to obtain a multi-source fusion magnetic field signal and send it; a signal analysis module is used to receive the multi-source fusion magnetic field signal, and generate a magnetic field strength value representing the strength of the weak magnetic field at the position to be detected according to the received multi-source fusion magnetic field signal.

[0034] It can be seen that the above solution of the present application has the following technical advantages:

[0035] (1) Hall sensors and magnetoresistive sensors have high sensitivity and can detect weak magnetic field changes. Miniaturized superconducting quantum interference devices are known for their extremely high sensitivity and can detect extremely weak magnetic field signals. By fusing the signals of these sensors through the fusion module, the sensitivity of the entire system can be further improved, thereby achieving more accurate detection of weak magnetic fields.

[0036] (2) Each sensor has its own unique measurement principle and characteristics. By fusing the signals of multiple sensors, we can make full use of their respective advantages, complement each other, and improve the overall measurement accuracy. The fusion module can calibrate and weight the signals of different sensors, thereby eliminating or reducing the impact of the measurement error of a single sensor and improving the accuracy of the measurement results.

[0037] (3) Different sensors have different sensitivities and anti-interference capabilities to different types of environmental interference. By fusing the signals of multiple sensors, the impact of environmental interference on a single sensor can be reduced, thus improving the stability and reliability of the system.

[0038] (4) Hall sensors and magnetoresistive sensors usually have a high response speed and can quickly detect changes in the magnetic field. Once the miniaturized superconducting quantum interference device reaches a stable working state, its response speed is also very fast. Through the fusion module and signal analysis module in the signal processing circuit, it is possible to quickly process and analyze multi-source signals, thereby ensuring that the entire system has a fast response speed. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The drawings constituting a part of this application are used to provide a further understanding of this application, so that other features, purposes and advantages of this application become more obvious. The schematic embodiment drawings and their descriptions of this application are used to explain this application and do not constitute an improper limitation on this application. In the drawings:

[0040] Figure 1 This is a schematic diagram of the process of a weak magnetic field detection system according to an embodiment of the present application. DETAILED DESCRIPTION

[0041] In order to enable those skilled in the art to better understand the solution of the present application, the following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of this application.

[0042] Figure 1 1 is a flow chart of a weak magnetic field detection system according to an embodiment of the present application. Figure 1 As shown, it includes:

[0043] A Hall sensor is used to detect a weak magnetic field at a position to be detected to generate and send a Hall signal;

[0044] A magnetoresistive sensor, used for detecting the weak magnetic field at the position to be detected to generate and send a magnetoresistive signal;

[0045] A miniaturized superconducting quantum interference device, used for detecting the weak magnetic field at the position to be detected to generate and send a superconducting quantum interference signal;

[0046] The signal processing circuit comprises at least:

[0047] A fusion module, electrically connected to the Hall sensor, the magnetoresistive sensor, and the miniaturized superconducting quantum interference device, respectively, for receiving the Hall signal, the magnetoresistive signal, and the superconducting quantum interference signal, and fusing the received Hall signal, the magnetoresistive signal, and the superconducting quantum interference signal to obtain a multi-source fused magnetic field signal and send it;

[0048] The signal analysis module is used to receive the multi-source fusion magnetic field signal and generate a magnetic field strength value representing the weak magnetic field strength at the position to be detected according to the received multi-source fusion magnetic field signal.

[0049] Optionally, the weak magnetic field detection system further includes: a temperature sensor for detecting the temperature at a position to be detected, so as to compensate the Hall signal, the magnetoresistance signal, and the superconducting quantum interference signal respectively according to the detected temperature.

[0050] It can be seen that the above solution of the present application has the following technical advantages:

[0051] (5) Hall sensors and magnetoresistive sensors have high sensitivity and can detect weak magnetic field changes. Miniaturized superconducting quantum interference devices are known for their extremely high sensitivity and can detect extremely weak magnetic field signals. By fusing the signals of these sensors through the fusion module, the sensitivity of the entire system can be further improved, thereby achieving more accurate detection of weak magnetic fields.

[0052] (6) Each sensor has its own unique measurement principle and characteristics. By fusing the signals of multiple sensors, we can make full use of their respective advantages, complement each other, and improve the overall measurement accuracy. The fusion module can calibrate and weight the signals of different sensors, thereby eliminating or reducing the impact of the measurement error of a single sensor and improving the accuracy of the measurement results.

[0053] (7) Different sensors have different sensitivities and anti-interference capabilities to different types of environmental interference. By fusing the signals of multiple sensors, the impact of environmental interference on a single sensor can be reduced, thus improving the stability and reliability of the system.

[0054] (8) Hall sensors and magnetoresistive sensors usually have a high response speed and can quickly detect changes in the magnetic field. Once the miniaturized superconducting quantum interference device reaches a stable working state, its response speed is also very fast. Through the fusion module and signal analysis module in the signal processing circuit, it is possible to quickly process and analyze multi-source signals, thereby ensuring that the entire system has a fast response speed.

[0055] Optionally, the Hall sensor also includes a first gain control circuit, which is used to determine the strength of the Hall signal, and adjust the gain of the Hall sensor to enhance the Hall signal according to the strength of the Hall signal so that the enhanced Hall signal reaches a set signal-to-noise ratio.

[0056] To this end, the above technical solution based on the first gain control circuit has the following technical advantages:

[0057] (1) The first gain control circuit is able to dynamically adjust the sensor gain according to the strength of the Hall signal. When the Hall signal is weak, by increasing the gain, the signal strength can be effectively enhanced while maintaining or reducing the noise level, thereby improving the signal-to-noise ratio. A high signal-to-noise ratio means that the useful information in the signal is more prominent and the noise interference is less, thereby improving the detection accuracy and reliability of the entire system.

[0058] (2) By adjusting the gain, the first gain control circuit can optimize the dynamic range of the Hall sensor. This means that the sensor can more effectively cover magnetic field signals of different strengths, and both weak and strong signals can be properly processed. This is especially important for detecting weak magnetic fields in complex environments, because such environments may contain magnetic field signals of different strengths.

[0059] (3) The strength of the magnetic field signal may change due to changes in environmental conditions and the object to be detected. The first gain control circuit can respond to these changes in real time and adjust the gain accordingly, thereby ensuring that the system can operate stably under various conditions. This adaptive capability improves the robustness of the system, making it more suitable for weak magnetic field detection in complex and changing environments.

[0060] (4) False positives and false negatives are common problems in weak magnetic field detection. By enhancing and optimizing the Hall signal through the first gain control circuit, the system can more accurately identify the real magnetic field signal and reduce the possibility of false positives and false negatives. This is crucial for application scenarios that require high-precision detection.

[0061] (5) The Hall signal enhanced by the first gain control circuit has a higher signal-to-noise ratio and a better dynamic range, which makes subsequent signal processing and analysis simpler and more efficient. The fusion module and signal analysis module in the signal processing circuit can more easily process these signals and generate more accurate magnetic field strength values.

[0062] Optionally, the first gain control circuit includes a peak detection circuit, a comparator, and a gain control element, the peak detection circuit is used to detect the peak value of the Hall signal, the comparator is used to compare the peak value with the reference signal to generate a gain control signal, and the gain control element is used to adjust the gain of the Hall sensor according to the gain control signal.

[0063] To this end, based on the first gain control circuit including a peak detection circuit, a comparator, and a gain control element, the following technical advantages are achieved:

[0064] (1) Through the peak detection circuit, the system can capture the peak value of the Hall signal in real time. Then, the comparator compares the detected peak value with a reference signal to determine whether the gain needs to be adjusted. This method ensures that the gain adjustment is based on the actual strength of the current signal, achieving adaptive gain control.

[0065] (2) The gain control element dynamically adjusts the gain of the Hall sensor according to the gain control signal to ensure that the Hall signal reaches the preset signal-to-noise ratio level. This real-time adjustment can effectively amplify weak signals and limit the growth of noise at the same time, thereby greatly improving signal quality and helping to more accurately detect weak magnetic fields.

[0066] (3) Adaptive gain adjustment ensures that the system works optimally regardless of changes in magnetic field strength. This helps optimize the overall performance of the system, especially when dealing with complex and dynamically changing magnetic field environments.

[0067] (4) By automatically adjusting the gain, the system no longer requires manual adjustment or calibration, thus simplifying the system design and maintenance process. At the same time, this also reduces the risk of human error and improves the reliability and stability of the system.

[0068] (5) In complex or changing environments, the magnetic field strength may change dramatically. The introduction of the first gain control circuit enables the system to respond quickly to these changes and automatically adjust the gain to maintain optimal performance. This capability enhances the robustness of the system, making it more suitable for weak magnetic field detection in harsh environments.

[0069] Optionally, the peak detection circuit includes a four-quadrant multiplier and a low-pass filter, the four-quadrant multiplier is used to convert the Hall signal into a unidirectional pulsating signal, and the low-pass filter is used to smooth the unidirectional pulse signal to obtain a smoothed pulse signal to represent the peak value of the Hall signal.

[0070] To this end, the peak detection circuit based on the four-quadrant multiplier and the low-pass filter has the following technical advantages:

[0071] (1) The four-quadrant multiplier can convert the Hall signal into a unidirectional pulse signal. This conversion helps to simplify the subsequent signal processing steps because the unidirectional pulse signal is easier to analyze and process in terms of waveform and amplitude.

[0072] (2) Hall signals may contain noise and interference, and direct peak detection may be affected by these factors. After being converted into a unidirectional pulsating signal by a four-quadrant multiplier and then smoothed by a low-pass filter, noise and interference can be effectively removed, thereby improving the accuracy of peak detection.

[0073] (3) The low-pass filter smoothes the unidirectional pulsating signal to obtain a smooth pulse signal, which more accurately reflects the peak value of the Hall signal. Smoothing can further reduce the influence of noise and interference, making peak detection more stable and reliable.

[0074] (4) By accurately detecting the peak value of the Hall signal, the first gain control circuit can accurately adjust the gain of the Hall sensor based on the peak value. This helps ensure that the system can operate in an optimal state under various conditions, improving the reliability and stability of the system.

[0075] (5) The optimization of the peak detection circuit enables the system to more accurately evaluate the strength of the Hall signal and adjust the gain as needed. This helps ensure that the system maintains high sensitivity and high accuracy even in weak magnetic field environments, thereby optimizing the overall performance of the system.

[0076] (6) The smooth pulse signal generated by the peak detection circuit represents the peak value of the Hall signal, making subsequent signal processing and analysis simpler and more efficient. The fusion module and signal analysis module in the signal processing circuit can process these signals more easily and generate more accurate magnetic field strength values.

[0077] Optionally, the gain control element includes: a coupling capacitor, a resistor voltage divider network, and a filter circuit, wherein the coupling capacitor is used to couple the gain control signal to the resistor voltage divider network, the resistor voltage divider network is used to perform voltage division processing on the gain control signal coupled thereto to obtain a voltage control signal, and the filter circuit filters the voltage control signal to adjust the gain of the Hall sensor.

[0078] To this end, the gain control element comprising the coupling capacitor, the resistor voltage divider network, and the filter circuit has the following technical advantages:

[0079] (1) The resistor voltage divider network can divide the gain control signal transmitted by the coupling capacitor to obtain an accurate voltage control signal. This voltage division process ensures the accuracy of the voltage control signal, thereby accurately adjusting the gain of the Hall sensor.

[0080] (2) The filter circuit filters the voltage control signal, which can remove noise and interference in the signal and improve the stability of the signal. This further ensures the accuracy and stability of the Hall sensor gain adjustment.

[0081] (3) The fast charging and discharging characteristics of the coupling capacitor enable the gain control signal to be quickly transmitted to the resistor divider network, achieving a fast response. At the same time, the processing speed of the resistor divider network and the filter circuit is also relatively fast, and the gain of the Hall sensor can be quickly adjusted to meet application scenarios with high real-time requirements.

[0082] (4) By adjusting the resistance value of the resistor in the resistor divider network, the amplitude of the voltage control signal can be easily changed, thereby realizing flexible adjustment of the Hall sensor gain. This design makes the system highly scalable and flexible, and can adapt to the needs of different application scenarios.

[0083] (5) The resistor divider network and filter circuit are both solid-state electronic components with high reliability and stability. They can work stably under various environmental conditions to ensure the accuracy and reliability of the Hall sensor gain adjustment.

[0084] Optionally, the magnetoresistive sensor has a plurality of set measuring axes, each measuring axis is configured with a symmetrical bridge composed of four magnetoresistive resistors, and each of the symmetrical bridges is connected to a preamplifier, so as to detect the weak magnetic field at the detected position in different directions along each measuring axis based on the stacked bridge to generate different magnetoresistive signal components, and the corresponding magnetoresistive signal components are amplified by the preamplifier to obtain amplified magnetoresistive signal components, and sent to the signal processing circuit to synthesize the different amplified magnetoresistive signal components to obtain the magnetoresistive signal and send it.

[0085] To this end, based on the magnetoresistive sensor having multiple measuring axes, each measuring axis is configured with a symmetrical bridge consisting of four magnetoresistive resistors, which has the following technical advantages:

[0086] The use of magnetoresistive sensors in weak magnetic field detection systems, by configuring a symmetrical bridge consisting of four magnetoresistive resistors for each measuring axis and connecting a preamplifier for signal amplification, brings the following significant technical benefits:

[0087] (1) The magnetoresistive sensor has multiple measurement axes, each of which can independently detect changes in the magnetic field in a specific direction. This multi-directional detection capability enables the system to fully capture magnetic field information, improving the accuracy and comprehensiveness of detection.

[0088] (2) The symmetrical bridge structure improves the sensor's sensitivity to magnetic field changes through a carefully designed magnetoresistive resistor configuration. This enables the sensor to detect weak magnetic field changes, making weak magnetic field detection possible.

[0089] (3) Each symmetrical bridge is connected to a preamplifier that can amplify the weak magnetic resistance signal component. This not only increases the signal amplitude, but also improves the signal-to-noise ratio, making subsequent signal processing easier and more accurate.

[0090] (4) The preamplifier is usually designed as a low-noise type, which can suppress the amplification of noise while amplifying the signal. This helps to reduce noise interference in the system and improve detection accuracy.

[0091] (5) The signal processing circuit can synthesize the amplified magnetoresistance signal components on different measurement axes to obtain the final magnetoresistance signal. This synthesis process can comprehensively consider the magnetic field information in multiple directions to obtain a more comprehensive and accurate detection result.

[0092] Optionally, the signal processing circuit includes: a low-noise amplifier, an analog-to-digital conversion circuit, a synchronous sampling circuit, and a microprocessor. The low-noise amplifier is used to filter the noise of the different amplified magnetoresistance signal components. The analog-to-digital conversion circuit is used to perform analog-to-digital conversion on the different amplified magnetoresistance signal components after the noise process to obtain corresponding digital components. The synchronous sampling circuit is used to synchronously sample the digital components corresponding to the different amplified magnetoresistance signal components to obtain sampling components. The microprocessor is used to perform vector synthesis on the synchronously sampled sampling components to obtain the magnetoresistance signal.

[0093] To this end, the signal processing circuit comprising: a low noise amplifier, an analog-to-digital conversion circuit, a synchronous sampling circuit, and a microprocessor has the following technical advantages:

[0094] (1) Low noise amplifiers can effectively filter noise from different amplified magnetoresistive signal components and improve the signal-to-noise ratio. This is especially important for weak magnetic field detection, because weak signals are more susceptible to noise interference. By reducing noise, the accuracy and reliability of detection can be improved.

[0095] (2) The analog-to-digital conversion circuit converts the noise-filtered analog signal into a digital signal, providing a basis for subsequent digital processing. Digital processing has higher flexibility and accuracy, and can process and analyze signals more accurately.

[0096] (3) The synchronous sampling circuit ensures synchronous sampling of the digital components of the different amplified magnetoresistive signal components, thereby maintaining the time relationship between the components. This is very important for subsequent vector synthesis, because only accurate time synchronization can ensure the accuracy of the synthesis result.

[0097] (4) The microprocessor is responsible for vector synthesis of the synchronously sampled components to obtain the final magnetic resistance signal. Vector synthesis can comprehensively consider the signal components in different directions to obtain more accurate magnetic field strength and direction information. This accuracy is crucial for weak magnetic field detection because it can provide more accurate magnetic field measurement results.

[0098] (5) By adopting this signal processing circuit, the performance of the entire weak magnetic field detection system has been significantly improved. Key indicators such as the system's sensitivity, resolution, measurement accuracy, and response time have all been improved, thus better meeting the needs of practical applications.

[0099] Optionally, the outside of the miniaturized superconducting quantum interference device is wrapped with multiple layers of superconducting material, and an insulating layer is arranged in the gap between two adjacent layers of superconducting material. Each layer of superconducting material is connected to a low-impedance path to dissipate the interference of external interfering electromagnetic fields on the weak magnetic field at the position to be detected. The material of the insulating layer is aluminum oxide or silicon dioxide, and the low-impedance path is a superconducting wire.

[0100] To this end, the miniaturized superconducting quantum interference device based on the above-mentioned externally wrapped multi-layer superconducting material has the following technical advantages:

[0101] (1) The design of wrapping multiple layers of superconducting materials on the outside of a miniaturized superconducting quantum interference device (SQUID) and providing an insulating layer in the gap between two adjacent layers of superconducting materials has brought the following significant technical benefits:

[0102] (2) The design of multi-layer superconducting materials forms an effective electromagnetic shielding layer, which can significantly reduce the interference of external electromagnetic fields on the internal SQUID. This is crucial to improving the sensitivity and accuracy of SQUID in weak magnetic field detection.

[0103] (3) The electromagnetic shielding effect is further enhanced by the insulating layer (such as alumina or silicon dioxide) between two adjacent layers of superconducting material. These insulating materials have good insulation properties and can prevent current leakage between superconducting layers, thereby ensuring the stable operation of the SQUID.

[0104] (4) Each layer of superconducting material is connected to a low-impedance path (such as a superconducting wire), which provides a dissipation path for external interfering electromagnetic fields. When an external electromagnetic field acts on the superconducting layer, the induced current will quickly dissipate through the low-impedance path, thereby reducing the impact on the SQUID.

[0105] (5) Improve system performance:

[0106] (6) By reducing external electromagnetic field interference, this design significantly improves the performance of SQUID in weak magnetic field detection. SQUID can measure weak magnetic field changes more accurately, providing a powerful tool for research in biomedicine, materials science and other fields.

[0107] (7) Using this design in a miniaturized SQUID not only retains its high sensitivity, but also makes the SQUID easier to integrate and deploy in various environments. This makes it possible to expand the application range of the SQUID.

[0108] Optionally, the weak magnetic field detection system also includes a magnetoelectric sensor, which is used to capture electromagnetic noise signals inside and outside the miniaturized superconducting quantum interference device, and amplify the electromagnetic noise signal through a preamplifier to increase the signal-to-noise ratio to a preset signal-to-noise ratio threshold, so as to input it into a notch filter for noise band extraction, and enable a signal generator to generate an anti-phase neutralization signal according to the phase of the noise band to feedback and offset the electromagnetic noise signal to eliminate the electromagnetic noise signal.

[0109] To this end, the weak magnetic field detection system further comprising a magnetoelectric sensor has the following technical advantages:

[0110] (1) Magnetoelectric sensors can capture electromagnetic noise signals inside and outside the miniaturized superconducting quantum interference device (SQUID). These noise signals are amplified by a preamplifier, so that the signal-to-noise ratio (SNR) can be increased to a preset signal-to-noise ratio threshold. A higher signal-to-noise ratio means that the detected signal is clearer, which is conducive to subsequent signal processing and analysis.

[0111] (2) The amplified electromagnetic noise signal is input into the notch filter, which can accurately extract the noise band. This precise extraction capability enables the system to perform targeted processing on specific noise frequency bands, improving the accuracy and efficiency of processing.

[0112] (3) According to the phase of the extracted noise band, the signal generator can generate a corresponding anti-phase neutralization signal. This anti-phase neutralization signal is opposite in phase to the original noise signal. When they are superimposed, they can cancel each other out, thereby effectively eliminating the electromagnetic noise signal.

[0113] (4) By generating an anti-phase neutralization signal and performing feedback to offset the electromagnetic noise signal, the system can significantly reduce or even eliminate the impact of electromagnetic noise on weak magnetic field detection. This feedback offset mechanism improves the system's anti-interference ability and makes the detection results more accurate and reliable.

[0114] Optionally, the signal processing circuit also includes: a polarization transmitter for generating rubidium atom polarization laser, and a xenon atom bias magnetic field for generating spinning xenon nuclei in a dark state, so as to spontaneously radiate the weak magnetic field at the position to be detected through coupling between the rubidium atom polarization laser and the spinning xenon nuclei in the dark state to amplify the weak magnetic field at the position to be detected, so that the Hall sensor, the magnetoresistive sensor, and the miniaturized superconducting quantum interference device respectively detect the amplified weak magnetic field at the position to be detected.

[0115] To this end, the signal processing circuit based on the polarized transmitter and the xenon atomic bias magnetic field has the following technical advantages:

[0116] (1) The coupling between the polarized laser light of rubidium atoms generated by the polarization emitter and the spin xenon nuclei in the dark state realizes the spontaneous emission amplification of the weak magnetic field at the detection position. This amplification mechanism can significantly increase the signal strength of the weak magnetic field, allowing subsequent sensors (such as Hall sensors, magnetoresistive sensors, and miniaturized superconducting quantum interference devices) to detect magnetic field changes more accurately.

[0117] (2) The amplification of weak magnetic fields directly improves the sensitivity of the detection system. Sensors such as Hall sensors, magnetoresistive sensors, and miniaturized superconducting quantum interference devices can capture amplified weak magnetic field signals, thereby improving the ability to respond to changes in weak magnetic fields.

[0118] (3) While amplifying weak magnetic field signals, the interference relative to noise will also decrease due to the increase in signal strength. This means that under the same noise environment, the system can more effectively extract useful magnetic field signals and reduce the impact of noise on the detection results.

[0119] (4) By improving detection sensitivity and reducing noise interference, the system can be applied to a wider range of fields, such as biomedicine, geological exploration, non-destructive testing, etc. In the biomedical field, it can be used to study brain activity, neural magnetic field, etc. In the field of geological exploration, it can be used to detect the magnetic field characteristics of underground materials; in the field of non-destructive testing, it can be used to detect the physical characteristics of materials such as strength and density.

[0120] (5) Due to the use of advanced signal processing technology (such as spontaneous emission amplification) and high-quality sensors (such as miniaturized superconducting quantum interference devices), the system has been significantly improved in terms of stability and reliability. Even in complex and changing environments, it can maintain high detection accuracy and stability.

[0121] (6) By amplifying and accurately detecting weak magnetic fields, the system can achieve high-precision magnetic field measurement. This is of great significance for experiments and application scenarios that require precise control of the magnetic field environment (such as precision measurement, quantum computing, etc.).

[0122] Optionally, the fusion module is specifically used to align the received Hall signal, the magnetoresistance signal, and the superconducting quantum interference signal in time and space to obtain calibrated magnetic field intensity components respectively, and perform Fourier transform on the calibrated magnetic field intensity components respectively to obtain a spectrum representation of each signal, perform multi-source fusion on the spectrum representation of each signal to obtain a multi-source fused spectrum representation, and convert the spectrum representation back to the time domain through inverse Fourier transform to obtain a multi-source fused magnetic field signal.

[0123] To this end, based on the above fusion module, the following technical benefits are achieved:

[0124] (1) The fusion module can ensure the consistency of the received Hall signal, magnetoresistive signal, and superconducting quantum interference signal in time and space. This alignment process is the basis for subsequent accurate fusion, which eliminates the errors that may be introduced due to the differences in response time and position of different sensors.

[0125] (2) After alignment, the fusion module calibrates the signal to obtain the calibrated magnetic field strength component. This step can further reduce the error and improve the accuracy of the magnetic field strength measurement.

[0126] (3) Performing Fourier transform on the calibrated magnetic field intensity components can obtain the spectrum representation of each signal. Fourier transform can convert the signal from the time domain to the frequency domain, which helps to analyze the frequency characteristics of the signal. In weak magnetic field detection, this helps to identify and analyze the different frequency components in the magnetic field signal.

[0127] (4) After obtaining the spectrum representation of each signal, the fusion module performs multi-source fusion to obtain a multi-source fusion spectrum representation. This step makes full use of the information from different sensors and improves the comprehensiveness and accuracy of the magnetic field signal through fusion. Multi-source fusion technology can integrate data from multiple sensors and reduce the limitations that may exist in a single sensor.

[0128] (5) Through inverse Fourier transform, the spectrum representation of multi-source fusion is converted back to the time domain to obtain a multi-source fusion magnetic field signal. This step converts the fused frequency domain signal back to a time domain signal that is easier to understand and analyze, providing a basis for subsequent magnetic field analysis and application.

[0129] (6) The fusion module significantly improves the accuracy and reliability of weak magnetic field detection through multi-source data fusion technology. The fusion of multi-source data can make full use of information from different sensors, reduce errors and uncertainties, and provide more accurate and reliable results for weak magnetic field detection.

[0130] (7) The fusion module can also enhance the robustness of the system. When a sensor fails or the data is abnormal, the fusion module can rely on the data of other sensors to maintain the normal operation of the system, thereby improving the stability and reliability of the system.

[0131] Optionally, the signal analysis module is used to receive the multi-source fusion magnetic field signal, and generate a magnetic field strength value representing the weak magnetic field strength at the position to be detected according to the received multi-source fusion magnetic field signal, including:

[0132] The multi-source fusion magnetic field signal is fitted with a pre-established Hall sensor physical model, a magnetoresistive sensor physical model, and a miniaturized superconducting quantum interference device physical model, respectively, to obtain a corresponding first magnetic field intensity estimate, a second magnetic field intensity estimate, and a third magnetic field intensity estimate; the first magnetic field intensity estimate, the second magnetic field intensity estimate, and the third magnetic field intensity estimate are Bayesian estimated to obtain a magnetic field intensity value characterizing the weak magnetic field intensity at the position to be detected.

[0133] To this end, the signal analysis module uses multi-source fusion magnetic field signals and physical model fitting in the weak magnetic field detection system, combined with the Bayesian estimation method, which brings the following significant technical benefits:

[0134] (1) By fitting the multi-source fusion magnetic field signal with the pre-established physical models of Hall sensors, magnetoresistive sensors, and miniaturized superconducting quantum interference devices, the response of each sensor to weak magnetic fields can be estimated more accurately. This physical model-based fitting method can reduce the impact of environmental noise and sensor errors on the measurement results, thereby improving the accuracy of the measurement.

[0135] (2) Fusion of data from multiple sensors can fully utilize the advantages of different sensors in terms of measurement range and accuracy, as well as their complementarity under different environmental conditions. This multi-source data fusion method can provide more comprehensive and accurate magnetic field information, making the final magnetic field strength value more reliable.

[0136] (3) Using the Bayesian estimation method to comprehensively process the magnetic field strength values ​​estimated by different sensors can obtain a more robust result. Bayesian estimation can consider the confidence and correlation of different estimated values, thereby obtaining an optimal magnetic field strength value that conforms to the actual situation. This method is particularly effective for dealing with complex and uncertain magnetic field environments.

[0137] (4) The signal analysis module is applicable to different types of weak magnetic field detection, whether static or dynamic, and can be adapted to different application scenarios by adjusting the parameters of the physical model and Bayesian estimation. This flexibility makes the module widely applicable.

[0138] (5) Through multi-source data fusion and Bayesian estimation methods, this module can reduce the impact of a single sensor failure on the overall system performance. Even if a sensor fails or the data is abnormal, the system can still rely on the data of other sensors to maintain normal operation, improving the reliability and stability of the system.

[0139] Optionally, the signal analysis module performs least squares fitting on the multi-source fusion magnetic field signal and a pre-established Hall sensor model, a magnetoresistive sensor model, and a miniaturized superconducting quantum interference device model, respectively, to obtain corresponding first magnetic field intensity estimation value, second magnetic field intensity estimation value, and third magnetic field intensity estimation value; based on the expected performance description values ​​of the Hall sensor, the magnetoresistive sensor, and the miniaturized superconducting quantum interference device, the first magnetic field intensity estimation value, the second magnetic field intensity estimation value, and the third magnetic field intensity estimation value are Bayesian estimated to determine the likelihood functions of the first magnetic field intensity estimation value, the second magnetic field intensity estimation value, and the third magnetic field intensity estimation value relative to the multi-source fusion magnetic field signal, respectively, so as to calculate the magnetic field intensity value characterizing the weak magnetic field intensity at the position to be detected based on the likelihood function and the joint probability distribution between the first magnetic field intensity estimation value, the second magnetic field intensity estimation value, and the third magnetic field intensity estimation value.

[0140] To this end, the signal analysis module uses a least squares-based fitting and Bayesian estimation method to process multi-source fusion magnetic field signals, and combines the expected performance description value of the sensor to determine the magnetic field strength value, which has the following technical benefits:

[0141] (1) Through least squares fitting, the relationship between the multi-source fusion magnetic field signal and each sensor model can be more accurately described, thereby obtaining a more accurate estimate of the magnetic field strength. This method can reduce errors caused by model mismatch or data noise and improve measurement accuracy.

[0142] (2) In the Bayesian estimation process, the expected performance description values ​​of Hall sensors, magnetoresistive sensors, and miniaturized superconducting quantum interference devices are considered. These description values ​​reflect the performance characteristics of the sensors under different conditions and can help the system more accurately evaluate the reliability and weight of the estimated values ​​of each sensor, thereby obtaining a more accurate magnetic field strength value.

[0143] (3) Combining the data from multiple sensors can fully utilize the advantages of different sensors in measurement range and accuracy, as well as their complementarity under different environmental conditions. Through least squares fitting and Bayesian estimation, the data from multiple sensors can be fused into a more reliable and accurate magnetic field strength value, improving the overall performance of the system.

[0144] (4) The Bayesian estimation method can take into account the confidence and correlation of different estimated values ​​and obtain the optimal magnetic field strength value by calculating the likelihood function and joint probability distribution. This method is particularly effective in dealing with complex and uncertain magnetic field environments and can improve the robustness and stability of the system.

[0145] (5) This method is applicable to different types of weak magnetic field detection, whether static or dynamic, and can be adapted to different application scenarios by adjusting the model parameters and the parameters of Bayesian estimation. This flexibility makes the system widely applicable.

[0146] (6) If new sensors need to be added or existing sensors need to be improved, a new model needs to be established and incorporated into the fitting and estimation process. At the same time, due to the use of a model-based fitting method, the maintenance of the system is relatively simple, requiring only regular updating and calibration of the model.

[0147] The present application also provides a weak magnetic field detection method, which includes:

[0148] The Hall sensor detects the weak magnetic field at the position to be detected to generate and send a Hall signal;

[0149] The magnetoresistive sensor detects the weak magnetic field at the position to be detected to generate a magnetoresistive signal and sends it;

[0150] The miniaturized superconducting quantum interference device detects the weak magnetic field at the position to be detected to generate a superconducting quantum interference signal and sends it;

[0151] The fusion module in the signal processing circuit is electrically connected to the Hall sensor, the magnetoresistive sensor, and the miniaturized superconducting quantum interference device, respectively, and is used to receive the Hall signal, the magnetoresistive signal, and the superconducting quantum interference signal, and fuse the received Hall signal, the magnetoresistive signal, and the superconducting quantum interference signal to obtain a multi-source fused magnetic field signal and send it;

[0152] The signal analysis module in the signal processing circuit receives the multi-source fusion magnetic field signal, and generates a magnetic field strength value representing the weak magnetic field strength at the position to be detected according to the received multi-source fusion magnetic field signal.

[0153] For exemplary descriptions of the various steps in the above method, please refer to the description of the above system.

[0154] It should be noted here that the above-mentioned system can be manufactured based on the micro-electromechanical system (MEMS) process. At the same time, through three-dimensional packaging and stacking technology, multiple sensors, signal processing circuits and even energy supply units (such as micro batteries or energy harvesters) can be efficiently and compactly integrated together to form a highly integrated microsystem suitable for wearable applications.

[0155] The above description is only a preferred embodiment of the present application and an explanation of the technical principles used. Those skilled in the art should understand that the scope of the invention involved in the present application is not limited to the technical solution formed by a specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the above invention concept. For example, the above features are replaced with the technical features with similar functions disclosed in this application (but not limited to) by each other.

Claims

1. A weak magnetic field detection system, characterized in that: include: A Hall sensor is used to detect a weak magnetic field at a position to be detected to generate and send a Hall signal; A magnetoresistive sensor, used for detecting a weak magnetic field at the position to be detected to generate and send a magnetoresistive signal; A miniaturized superconducting quantum interference device, used to detect the weak magnetic field at the position to be detected to generate and send a superconducting quantum interference signal; The signal processing circuit comprises at least: A fusion module, electrically connected to the Hall sensor, the magnetoresistive sensor, and the miniaturized superconducting quantum interference device, respectively, for receiving the Hall signal, the magnetoresistive signal, and the superconducting quantum interference signal, and fusing the received Hall signal, the magnetoresistive signal, and the superconducting quantum interference signal to obtain a multi-source fused magnetic field signal and send it; A signal analysis module, used for receiving the multi-source fusion magnetic field signal, and generating a magnetic field strength value representing the weak magnetic field strength at the position to be detected according to the received multi-source fusion magnetic field signal; The Hall sensor further includes a first gain control circuit, which is used to determine the strength of the Hall signal and, according to the strength of the Hall signal, adjust the gain of the Hall sensor to enhance the Hall signal so that the enhanced Hall signal reaches a set signal-to-noise ratio; The first gain control circuit includes a peak detection circuit, a comparator, and a gain control element. The peak detection circuit is used to detect the peak value of the Hall signal. The comparator is used to compare the peak value with a reference signal to generate a gain control signal. The gain control element is used to adjust the gain of the Hall sensor according to the gain control signal. Wherein, the peak detection circuit includes a four-quadrant multiplier and a low-pass filter, the four-quadrant multiplier is used to convert the Hall signal into a unidirectional pulse signal, and the low-pass filter is used to smooth the unidirectional pulse signal to obtain a smoothed pulse signal to represent the peak value of the Hall signal; Among them, the gain control element includes: a coupling capacitor, a resistor voltage divider network, and a filter circuit. The coupling capacitor is used to couple the gain control signal to the resistor voltage divider network. The resistor voltage divider network is used to perform voltage division processing on the gain control signal coupled thereto to obtain a voltage control signal. The filter circuit filters the voltage control signal to adjust the gain of the Hall sensor.

2. The weak magnetic field detection system according to claim 1, characterized in that: The weak magnetic field detection system further includes: a temperature sensor for detecting the temperature at a position to be detected, so as to compensate the Hall signal, the magnetoresistance signal, and the superconducting quantum interference signal respectively according to the detected temperature.

3. The weak magnetic field detection system according to claim 2, characterized in that: The magnetoresistive sensor has a plurality of set measuring axes, each measuring axis is configured with a symmetrical bridge composed of four magnetoresistive resistors, each of the symmetrical bridges is connected to a preamplifier, so as to detect the weak magnetic field at the position to be detected in different directions along each measuring axis based on the symmetrical bridge to generate different magnetoresistive signal components, and the corresponding magnetoresistive signal components are amplified by the preamplifier to obtain amplified magnetoresistive signal components, and sent to the signal processing circuit to synthesize the different amplified magnetoresistive signal components to obtain the magnetoresistive signal and send it.

4. The weak magnetic field detection system according to claim 3, characterized in that: The signal processing circuit includes: a low-noise amplifier, an analog-to-digital conversion circuit, a synchronous sampling circuit, and a microprocessor. The low-noise amplifier is used to filter the noise of the different amplified magnetoresistance signal components. The analog-to-digital conversion circuit is used to perform analog-to-digital conversion on the different amplified magnetoresistance signal components after noise filtering to obtain corresponding digital components. The synchronous sampling circuit is used to synchronously sample the digital components corresponding to the different amplified magnetoresistance signal components to obtain sampling components. The microprocessor is used to perform vector synthesis on the synchronously sampled sampling components to obtain the magnetoresistance signal.

5. The weak magnetic field detection system according to claim 1, characterized in that: The outside of the miniaturized superconducting quantum interference device is wrapped with multiple layers of superconducting material, and an insulating layer is arranged in the gap between two adjacent layers of superconducting material. Each layer of superconducting material is connected to a low-impedance path to dissipate the interference of external interfering electromagnetic fields on the weak magnetic field at the position to be detected. The material of the insulating layer is aluminum oxide or silicon dioxide, and the low-impedance path is a superconducting wire.

6. The weak magnetic field detection system according to claim 5, characterized in that: The weak magnetic field detection system also includes a magnetoelectric sensor, which is used to capture electromagnetic noise signals inside and outside the miniaturized superconducting quantum interference device, and amplify the electromagnetic noise signal through a preamplifier to increase the signal-to-noise ratio to a preset signal-to-noise ratio threshold, so as to input it into a notch filter for noise band extraction, and enable a signal generator to generate an anti-phase neutralization signal according to the phase of the noise band to feedback and offset the electromagnetic noise signal to eliminate the electromagnetic noise signal.

7. The weak magnetic field detection system according to claim 1, characterized in that: The signal processing circuit also includes: a polarization transmitter for generating rubidium atom polarization laser, and a xenon atom bias magnetic field for generating spin xenon nuclei in a dark state, so as to spontaneously radiate the weak magnetic field at the position to be detected through coupling between the rubidium atom polarization laser and the spin xenon nuclei in the dark state to amplify the weak magnetic field at the position to be detected, so that the Hall sensor, the magnetoresistive sensor, and the miniaturized superconducting quantum interference device respectively detect the amplified weak magnetic field at the position to be detected.

8. The weak magnetic field detection system according to claim 1, characterized in that: The fusion module is specifically used to align the received Hall signal, the magnetoresistance signal, and the superconducting quantum interference signal in time and space to obtain calibrated magnetic field intensity components respectively, and perform Fourier transform on the calibrated magnetic field intensity components respectively to obtain the spectrum representation of each signal, perform multi-source fusion on the spectrum representation of each signal to obtain a multi-source fused spectrum representation, and convert the spectrum representation back to the time domain through inverse Fourier transform to obtain a multi-source fused magnetic field signal.

9. A weak magnetic field detection method using the weak magnetic field detection system according to any one of claims 1 to 8, characterized in that: include: The Hall sensor detects the weak magnetic field at the position to be detected to generate and send a Hall signal; The magnetoresistive sensor detects the weak magnetic field at the position to be detected to generate a magnetoresistive signal and sends it; The miniaturized superconducting quantum interference device detects the weak magnetic field at the position to be detected to generate and send a superconducting quantum interference signal; The fusion module in the signal processing circuit is electrically connected to the Hall sensor, the magnetoresistive sensor, and the miniaturized superconducting quantum interference device, respectively, and is used to receive the Hall signal, the magnetoresistive signal, and the superconducting quantum interference signal, and fuse the received Hall signal, the magnetoresistive signal, and the superconducting quantum interference signal to obtain a multi-source fused magnetic field signal and send it; The signal analysis module in the signal processing circuit receives the multi-source fusion magnetic field signal, and generates a magnetic field strength value representing the weak magnetic field strength at the position to be detected based on the received multi-source fusion magnetic field signal.

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