Microwave magnetic field measurement method and system

Abstract

The invention relates to the technical field of microwave magnetic field measurement, and discloses a microwave magnetic field measurement method and system, and the method comprises the steps: installing a plurality of magnetic field shielding units for transmitting a magnetic field shielding region at the roof of each floor; mapping the three-dimensional space magnetic field data into two-dimensional plane magnetic field data according to the floor height; executing a magnetic field change difference distinguishing strategy, and collecting and calculating magnetic field data variation of plane position points in the examination room in real time; setting an external disturbance critical distance to form an external disturbance critical edge surrounding the examination room; executing an external interference buffer area shielding strategy, dividing an external interference critical edge according to a magnetic field shielding area, defining an external interference buffer area, and calculating an external interference risk value based on the magnetic field data variable quantity and the personnel movement track; and executing a secondary shielding collaborative coverage strategy, adjusting the shielding strength of the unit I according to the external interference risk value of the external interference buffer area, and adjusting the emission directions of the unit I and the unit II to shield the external interference buffer area, thereby improving the stability of the internal electromagnetic environment of the examination room.

Description

Technical Field

[0001] This invention relates to the field of microwave magnetic field measurement technology, specifically to a microwave magnetic field measurement method and system. Background Technology

[0002] Microwave magnetic field control in examination rooms can effectively prevent interference from communication equipment, ensuring fairness and order in examinations. By monitoring and dynamically shielding microwave signals in real time, it can block the wireless communication of cheating devices, improve the security and management level of the examination room, and ensure a clean and stable electromagnetic environment for the examination.

[0003] In existing technologies, most examination room shielding systems rely primarily on fixed-frequency electromagnetic shielding devices, lacking the ability to finely and dynamically adjust for microwave frequencies. Current solutions typically cannot distinguish between personnel movement and communication equipment interference in real time, easily leading to false alarms or missed alarms, disrupting examination room order. Furthermore, unreasonable shielding coverage planning, dispersed shielding unit layouts, and a lack of coordinated adjustment mechanisms result in uneven shielding effectiveness, with blind spots and dead zones. More critically, the movement and disturbance of personnel outside the examination room have a significant impact on the magnetic field environment inside, and existing technologies generally fail to specifically analyze and handle magnetic field disturbances caused by external personnel activity, lacking targeted buffer zone delineation and risk assessment mechanisms. This makes it difficult for the shielding system to effectively cope with dynamic changes in external interference sources during actual operation, affecting overall shielding effectiveness and the stability of the electromagnetic environment inside the examination room.

[0004] This solution proposes a microwave magnetic field measurement method and system to address the problems mentioned in the background section. Summary of the Invention

[0005] This invention provides a microwave magnetic field measurement method and system to help solve the problems mentioned in the background art.

[0006] This invention provides the following technical solution: a microwave magnetic field measurement method, comprising:

[0007] Multiple magnetic field shielding units are installed on the roof of each floor to shield the magnetic field, and the magnetic field shielding units can adjust the emission direction.

[0008] Establish a two-dimensional coordinate system by selecting any point on the floor as the origin;

[0009] Multiple magnetic field sensors are deployed in the floor to collect three-dimensional spatial magnetic field data, and the three-dimensional spatial magnetic field data is mapped into two-dimensional planar magnetic field data according to the floor height.

[0010] Filter any exam room currently holding an exam on this floor based on the exam schedule;

[0011] Implement a strategy to differentiate magnetic field changes, collect and calculate the changes in magnetic field data at planar locations in the examination room in real time, and use this data to distinguish between personnel movement and interference from communication equipment.

[0012] An alarm will be triggered if interference from communication devices is detected in the examination room.

[0013] Set an external disturbance critical distance, and expand the preset external disturbance critical distance outward based on the four boundaries of the examination room to form an external disturbance critical edge around the examination room.

[0014] Implement an external disturbance buffer shielding strategy, divide the external disturbance critical edge according to the magnetic field shielding area and define the external disturbance buffer, and calculate the external disturbance risk value based on the change in magnetic field data and personnel movement trajectory;

[0015] The external disturbance buffer is rectangular;

[0016] Obtain the two magnetic field shielding units adjacent to the external disturbance buffer, and name them Unit 1 and Unit 2;

[0017] A two-level shielding and coordinated coverage strategy is implemented. The shielding strength of Unit 1 is adjusted according to the external interference risk value of the external interference buffer, and the transmission directions of Unit 1 and Unit 2 are adjusted to shield the external interference buffer.

[0018] Optionally, the installation of multiple magnetic field shielding units for transmitting magnetic field shielding areas on the roof of each floor includes:

[0019] The magnetic field shielding region is conical in space, with the apex of the magnetic field shielding region located at the magnetic field shielding unit, and the emission angle being half the apex angle of the cone;

[0020] The specific steps for calculating the number of magnetic field shielding units to be installed on any floor are as follows:

[0021] The emission angle of the fixed magnetic field shielding unit is ;

[0022] Get floor height ;

[0023] Calculate the coverage radius of the magnetic field shielding area on the floor. , ;

[0024] The magnetic field shielding area is circular on the floor surface. Calculate the area of ​​the square inscribed in the circular shape. , ,in, Let be the side length of the inscribed square;

[0025] Get the floor area of ​​the building ;

[0026] calculate ,in, The number of magnetic field shielding units to be installed;

[0027] The floor area is divided into multiple grids with side lengths of... A square is formed, and the midpoint of each square is vertically mapped onto the rooftop for installing the magnetic field shielding unit.

[0028] Optionally, mapping the three-dimensional spatial magnetic field data into two-dimensional planar magnetic field data according to the floor height includes:

[0029] A three-dimensional coordinate system is obtained by establishing a vertically upward z-axis at the origin of the two-dimensional coordinate system;

[0030] The spatial position point measured by the magnetic field sensor at time t is obtained as follows. Three-dimensional spatial magnetic field data ,in, This represents the coordinates of a point in a three-dimensional coordinate system.

[0031] The magnetic field data is in vector form;

[0032] Three-dimensional spatial magnetic field data of spatial locations at different heights on the same z-axis are obtained in a three-dimensional coordinate system, and the three-dimensional spatial magnetic field data are mapped to the z-axis to obtain... ;

[0033] The two-dimensional planar magnetic field data are obtained by weighted averaging all mapped three-dimensional spatial magnetic field data along the z-axis. ;

[0034] ,in, The weights of spatial location points, This represents the coordinates of a spatial point mapped to a two-dimensional coordinate system.

[0035] Optionally, the implementation of the magnetic field change difference differentiation strategy involves real-time collection and calculation of magnetic field data changes at planar locations within the examination room to differentiate between personnel movement and communication equipment interference, including:

[0036] Regarding the floor plan location of the examination room:

[0037] Calculate the planar position point Magnetic field data change ;

[0038] ,in, Here are the two-dimensional planar magnetic field data at time t. for Two-dimensional planar magnetic field data at time t. For time step;

[0039] Set the threshold for magnetic field change ;

[0040] Set planar position point binary functions , among which, when hour, ,when , ;

[0041] A movement region is defined, which represents a circular planar region of the magnetic field disturbed by the movement of personnel, and simultaneously contains multiple planar position points with the same binary function.

[0042] The number of planar location points contained in the moving area is denoted as . ;

[0043] The number of planar locations in a moving region where the value of a binary function is simultaneously equal to 1 is denoted as . ;

[0044] Set quantity ratio threshold ;

[0045] like If so, it is determined that the moving region simultaneously contains multiple planar position points with the same binary function;

[0046] The center of the moving area represents the movement trajectory of the personnel over time;

[0047] Check if there is a moving area in the two-dimensional coordinate system where the examination room is located;

[0048] If a movement area exists, the change in the magnetic field within the examination room is determined to be caused by the movement of people.

[0049] If no movement region exists, then determine the time step at multiple time steps. Does there exist planar location points within the area that satisfy the condition that the change in magnetic field data is greater than or equal to the threshold of magnetic field change?

[0050] If the aforementioned planar location point exists, it is determined that the change in the magnetic field within the examination room is due to interference from communication equipment.

[0051] Optionally, the implementation of the external disturbance buffer shielding strategy involves dividing and defining the external disturbance critical edge according to the magnetic field shielding area, and calculating the external disturbance risk value based on the change in magnetic field data and personnel movement trajectory, including:

[0052] The area between the critical edge of the external disturbance and the boundaries of the examination room is divided into multiple external disturbance buffer zones according to the magnetic field shielding area in which it is located.

[0053] For any external disturbance buffer, select multiple planar locations on the buffer and obtain the magnetic field data change at each location. Calculate the mean value, and record the result as the mean magnetic field change. ;

[0054] When a moving region is detected in the external disturbance buffer:

[0055] Obtain the movement trajectory of the center of the moving region over time. The position of the center of the circle at any given time is recorded as the starting position. The position of the center of the circle at any given moment is recorded as the ending position;

[0056] Establish a direction vector from the starting position to the ending position. ;

[0057] Establish normal vectors pointing from the four boundaries of the examination room to the critical edge of the external disturbance. ;

[0058] Calculate the angle between the direction vector and the normal vector. , ,in, For dot product, For the module length;

[0059] Obtain the included angles of all moving areas, calculate the mean of the included angles, and record the result as the average included angle. ;

[0060] Calculate the external disturbance risk value of the external disturbance buffer. , ,in, The weights are the average values ​​of the magnetic field changes. The weight is the average value of the included angle.

[0061] Optionally, the implementation of the secondary shielding collaborative coverage strategy, adjusting the shielding strength of unit one according to the external disturbance risk value of the external disturbance buffer, includes:

[0062] normal vector along the outer disturbance buffer Two adjacent magnetic field shielding units were obtained in sequence and named Unit 1 and Unit 2 in order of distance from the external disturbance buffer zone from near to far.

[0063] Obtain the initial shielding strength of unit 1 ;

[0064] Obtain the external disturbance risk value of the external disturbance buffer. ;

[0065] Calculate the shielding strength of the final adjustment unit 1 , ,in, The adjustment coefficient reflects the degree of influence of the external disturbance risk value on the shielding strength of element one.

[0066] Optionally, the adjustment of the transmission directions of unit one and unit two for shielding the external interference buffer includes:

[0067] The emission direction of the magnetic field shielding device is along the axis of the magnetic field shielding area;

[0068] Adjust the emission direction of Unit 1 so that the axis of the magnetic field shielding area corresponding to Unit 1 is connected to the center point of the external disturbance buffer.

[0069] The planar location point on the external disturbance buffer where the binary function is 1 is denoted as the disturbance point;

[0070] Obtain the coordinates of all perturbation points in a two-dimensional coordinate system, calculate the mean of the horizontal axis coordinates and the mean of the vertical axis coordinates, and obtain the coordinates of the global center point. ;

[0071] For arbitrary external disturbance buffers:

[0072] The coordinates of the partition center point are obtained by calculating the mean of the x and y coordinates of the disturbance points on the external disturbance buffer. ;

[0073] Calculate the Euclidean distance from the partition center point to the global center point. ;

[0074] Update the coordinates of the center point of the outer disturbance buffer partition to [value]. , ,in, Used to control the decay rate;

[0075] Let be a decreasing function, representing the Euclidean distance. The smaller the value, the smaller the adjustment range of the partition center point, and the Euclidean distance. The larger the value, the greater the adjustment range of the partition center point;

[0076] Adjust the emission direction of Unit 2 so that the axis of the magnetic field shielding area corresponding to Unit 2 is connected to the center point of the partition.

[0077] A microwave magnetic field measurement system, comprising:

[0078] The magnetic field shielding unit deployment module is used to install multiple magnetic field shielding units on the roof of each floor, set the emission direction, and calculate the coverage radius according to the floor height to achieve basic deployment of magnetic field shielding for the entire floor.

[0079] The magnetic field data mapping module is used to collect three-dimensional spatial magnetic field data from multiple magnetic field sensors within the floor and map it into two-dimensional planar magnetic field data according to the floor height.

[0080] The magnetic field change difference differentiation module is used to calculate the change in magnetic field data at a planar location point in real time, and to differentiate between personnel movement and communication equipment interference based on a binary function and a movement area determination strategy.

[0081] The external disturbance buffer risk assessment module is used to divide the external disturbance critical edge into external disturbance buffer zones according to the magnetic field shielding area, and calculate the external disturbance risk value based on the angle between the average magnetic field change and the direction of movement.

[0082] The secondary shielding coordination adjustment module is used to adjust the shielding strength and emission direction of adjacent magnetic field shielding units according to the external disturbance risk value, combined with the decreasing adjustment strategy of the global center point and the regional center point.

[0083] The present invention has the following beneficial effects:

[0084] 1. This microwave magnetic field measurement method, by installing multiple adjustable magnetic field shielding units on the roof of each floor, combined with a two-dimensional coordinate system of the floors and three-dimensional magnetic field data acquisition from multiple sensors, achieves real-time monitoring and dynamic shielding of the microwave magnetic field environment in the examination room. The magnetic field shielding units form a spatial shielding area, accurately distinguishing interference from personnel movement and communication equipment within the examination room. By setting critical distances and buffer zones for external interference, the influence range of external interference in the examination room is effectively defined, ensuring a safe and stable electromagnetic environment inside the examination room. The two-level shielding collaborative coverage strategy enables the shielding units to intelligently adjust their transmission direction and intensity, achieving dynamic protection of the external interference buffer zone and improving the overall shielding effect.

[0085] 2. This microwave magnetic field measurement method clarifies the spatial morphology and coverage area calculation method of the transmission area of ​​the magnetic field shielding unit, providing a scientific basis for the quantity configuration and spatial layout of the shielding units. By fixing the transmission angle and combining it with the floor height to calculate the shielding coverage radius, and then dividing the floor into a grid, the installation positions of the shielding units are precisely planned to achieve reasonable and efficient coverage. This avoids blindly increasing the number of shielding units, saves resources and costs, and ensures the uniformity and integrity of the shielding coverage. The reasonable installation layout improves the overall effectiveness of the shielding system, ensures that there are no obvious dead zones in the shielded area, and improves the ability to suppress microwave signals.

[0086] 3. This microwave magnetic field measurement method achieves data dimensionality reduction by mapping three-dimensional spatial magnetic field data to two-dimensional planar magnetic field data, simplifying subsequent data processing and analysis. The mapping employs a weighted averaging method, considering the magnetic field contribution at different heights, ensuring the two-dimensional data accurately reflects the actual magnetic field environment. This guarantees monitoring accuracy while reducing computational complexity, facilitating real-time and rapid monitoring response. The converted two-dimensional planar data conforms to the main activity plane of personnel within the examination room, facilitating intuitive display and analysis, and supporting shielding and risk assessment strategies based on planar location points.

[0087] 4. This microwave magnetic field measurement method employs a strategy to differentiate magnetic field variations by calculating the magnetic field changes at planar locations in real time. Combined with binary functions and statistics on moving areas, it effectively distinguishes between personnel movement and communication equipment interference. It uses a threshold value proportional to the binary function within the moving area to determine movement disturbances, and combines this with the determination of communication interference based on the continuous exceedance of the magnetic field threshold within a time step. This achieves accurate identification of different disturbance sources, reducing false alarms and missed alarms, ensuring the relevance and effectiveness of alarms, and preventing unnecessary alarms from disrupting the examination room order. By differentiating different interference sources, it can intelligently adjust shielding strategies, improving the electromagnetic safety management level of the examination room environment and enhancing system stability and practical value.

[0088] 5. This microwave magnetic field measurement method refines the shielding strategy of external disturbance buffer zone division, specifying the area between the external disturbance critical edge and the perimeter of the examination room. It calculates the external disturbance risk value by combining the average magnetic field change and personnel movement trajectories. Through multi-angle data fusion, it accurately quantifies the external disturbance risk. Utilizing the angle analysis between the direction vector and the normal vector, and considering the relationship between the personnel movement direction and the examination room boundary, it achieves dynamic risk assessment.

[0089] 6. This microwave magnetic field measurement method proposes a dynamic adjustment method for the shielding strength of Unit 1, addressing the external disturbance risk value of the external disturbance buffer zone. Through coupled calculation of the risk value and adjustment coefficient, the shielding strength is intelligently amplified or weakened, achieving optimized allocation of shielding resources and avoiding blind over- or under-shielding. The joint adjustment strategy for the transmission directions of Unit 1 and Unit 2, based on the disturbance point and its two-dimensional coordinate mean, uses a decreasing function to correct the position of the partition center point, ensuring more accurate and effective coverage of key interference points by the shielding area. Multi-unit collaborative adjustment achieves seamless spatial shielding coverage, overcoming the limitations of individual unit actions. The introduction of the decreasing function effectively balances global and local shielding requirements, improving the uniformity and stability of the shielding. Attached Figure Description

[0090] Figure 1 This is a schematic diagram of the method flow of the present invention.

[0091] Figure 2 This is a schematic diagram of the system modules of the present invention.

[0092] Figure 3 This is a schematic diagram of the external disturbance buffer of the present invention. Detailed Implementation

[0093] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0094] Example 1, refer to Figure 1 A microwave magnetic field measurement method, comprising:

[0095] The primary purpose of existing exam room shielding is to block high-frequency wireless signals, such as mobile phone signals, Wi-Fi, Bluetooth, and 4G / 5G. These signals typically operate at frequencies ranging from hundreds of MHz to several GHz, falling within the microwave band. High-frequency wireless signals are essentially electromagnetic waves, containing both simultaneously changing electric and magnetic fields. This solution employs active dynamic shielding technology based on microwave band magnetic fields. It can collect magnetic field data in real time and intelligently adjust the magnetic field emission direction and intensity of the shielding unit, achieving precise shielding against disturbances inside and outside the exam room. It can be deployed independently or combined with traditional electric field shielding technologies (such as Faraday cages and radio frequency shielding materials) to further enhance the shielding effect and improve the overall safety and stability of the electromagnetic environment.

[0096] Multiple magnetic field shielding units are installed on the roof of each floor to shield the transmission magnetic field area. These magnetic field shielding units have adjustable transmission direction and include:

[0097] A magnetic field shielding unit is a transmitting device that generates and controls frequency magnetic fields (especially microwave band magnetic fields). By adjusting the transmission direction and intensity, it intervenes in the magnetic field environment of a specific area in space. It consists of:

[0098] Transmitter: An antenna structure used to generate microwave magnetic field components; it may be a directional microwave antenna or a loop antenna.

[0099] Power amplifier: Enhances the power of the transmitted signal and ensures the coverage strength of the magnetic field.

[0100] Control module: Adjusts the transmission direction (such as electronic scanning or mechanical adjustment), power, and transmission frequency.

[0101] Signal processing unit: Based on feedback from the magnetic field sensor, it intelligently adjusts the transmission parameters and dynamically shields the signal.

[0102] Installation structure: Fixed on the roof or in a designated location, supporting spatial orientation adjustment.

[0103] The hardware device is achievable with existing technology, and the technical path is feasible. It is similar to the directional antenna array of a wireless communication base station, capable of transmitting high-frequency signals and precisely controlling the direction and intensity.

[0104] The magnetic field shielding region is conical in space, with the apex of the magnetic field shielding region located at the magnetic field shielding unit, and the emission angle being half the apex angle of the cone;

[0105] The specific steps for calculating the number of magnetic field shielding units to be installed on any floor are as follows:

[0106] The emission angle of the fixed magnetic field shielding unit is ;

[0107] Get floor height ;

[0108] Calculate the coverage radius of the magnetic field shielding area on the floor. , ;

[0109] The magnetic field shielding area is circular on the floor surface. Calculate the area of ​​the square inscribed in the circular shape. , ,in, Let be the side length of the inscribed square;

[0110] Get the floor area of ​​the building ;

[0111] calculate ,in, The number of magnetic field shielding units to be installed;

[0112] The floor area is divided into multiple grids with side lengths of... A square is formed, and the midpoint of each square is vertically mapped onto the rooftop for installing the magnetic field shielding unit.

[0113] Establish a two-dimensional coordinate system by selecting any point on the floor as the origin;

[0114] Multiple magnetic field sensors are deployed throughout the building to collect three-dimensional spatial magnetic field data. This three-dimensional spatial magnetic field data is then mapped to two-dimensional planar magnetic field data based on the floor height, including:

[0115] A three-dimensional coordinate system is obtained by establishing a vertically upward z-axis at the origin of the two-dimensional coordinate system;

[0116] The spatial position point measured by the magnetic field sensor at time t is obtained as follows. Three-dimensional spatial magnetic field data ,in, This represents the coordinates of a point in a three-dimensional coordinate system.

[0117] Assuming that at the same horizontal position (x=5, y=5), the sensor collects magnetic field data at different heights z, z=1, 2, 3, 4 m;

[0118] The magnetic field data is in vector form;

[0119] Three-dimensional spatial magnetic field data at different heights along the same z-axis are acquired in a three-dimensional coordinate system, and the three-dimensional spatial magnetic field data are mapped to the z-axis. The vector mapping follows existing techniques to obtain... ;

[0120] The collected magnetic field data (unit μT) are as follows:

[0121] ; ; ; ;

[0122] The two-dimensional planar magnetic field data are obtained by weighted averaging all mapped three-dimensional spatial magnetic field data along the z-axis. ;

[0123] ,in, The weights of spatial location points, This represents the coordinates of a spatial point mapped to a two-dimensional coordinate system.

[0124] Converting three-dimensional magnetic field data into two-dimensional planar magnetic field data is primarily to adapt to the actual two-dimensional spatial activity scenarios in the examination room, simplify data processing, improve computational efficiency, and highlight the characteristics of magnetic field changes on the examination room plane. This helps to more accurately monitor personnel movement and communication equipment interference, enabling effective shielding strategies and risk assessments.

[0125] Filter any exam room currently holding an exam on this floor based on the exam schedule;

[0126] A strategy for differentiating differences in magnetic field changes is implemented, and the changes in magnetic field data at planar locations within the examination room are collected and calculated in real time to distinguish between interference from personnel movement and communication equipment, including:

[0127] Regarding the floor plan location of the examination room:

[0128] Calculate the planar position point Magnetic field data change ;

[0129] ,in, Here are the two-dimensional planar magnetic field data at time t. for Two-dimensional planar magnetic field data at time t. For time step;

[0130] Set the threshold for magnetic field change ;

[0131] Set planar position point binary functions ,when hour, ;

[0132] A movement area is defined, which represents a circular planar area of ​​the magnetic field disturbed by the movement of personnel. In this embodiment, the movement area with a radius of 3m contains multiple planar position points with the same binary function at the same time.

[0133] The number of planar location points contained in the moving area is denoted as . ;

[0134] The number of planar locations in a moving region where the value of a binary function is simultaneously equal to 1 is denoted as . ;

[0135] Set quantity ratio threshold ;

[0136] like Then the moving region simultaneously contains multiple planar position points with the same binary function;

[0137] The center of the moving area represents the movement trajectory of the personnel over time;

[0138] Check if there is a moving area in the two-dimensional coordinate system where the examination room is located;

[0139] If a movement area exists, the change in the magnetic field within the examination room is determined to be caused by the movement of people.

[0140] Humans and carried metal objects can affect the distribution of the surrounding magnetic field. When a person or object moves, it cuts magnetic field lines, causing changes in the strength and direction of the magnetic field. This movement alters the magnetic field environment received by magnetic field sensors, creating fluctuations. Furthermore, carried electronic devices can also emit electromagnetic signals, further interfering with the magnetic field.

[0141] If no movement region exists, then determine the time step within 3 time steps. Does there exist planar location points within the area that satisfy the condition that the change in magnetic field data is greater than or equal to the threshold of magnetic field change?

[0142] If the aforementioned planar location point exists, it is determined that the change in the magnetic field within the examination room is due to interference from communication equipment.

[0143] An alarm will be triggered if interference from communication devices is detected in the examination room.

[0144] It can effectively distinguish between spatially concentrated magnetic field changes caused by human activities and localized and continuous magnetic field interference caused by communication equipment, achieve highly accurate interference source identification, reduce false alarms, and ensure examination room order.

[0145] In this embodiment, refer to Figure 3 A critical distance for external disturbance was set. Based on the four boundaries of the examination room, the preset critical distance for external disturbance was extended outward to form a critical edge for external disturbance around the examination room.

[0146] When both personnel movement and magnetic field changes caused by communication equipment interference are detected simultaneously, the disturbance caused by personnel movement will be prioritized to avoid false alarms that could disrupt the examination room order. Only if the abnormal magnetic field change persists after personnel movement has ended will it be considered communication equipment interference and an alarm be triggered.

[0147] An external disturbance buffer shielding strategy is implemented, dividing the external disturbance critical edge according to the magnetic field shielding area and defining the external disturbance buffer zone. The external disturbance risk value is calculated based on changes in magnetic field data and personnel movement trajectories, including:

[0148] The area between the critical edge of the external disturbance and the boundaries of the examination room is divided into multiple external disturbance buffer zones according to the magnetic field shielding area in which it is located.

[0149] The magnetic field shielding area is the effective range covered by the magnetic field shielding unit. Within this range, the shielding unit can control and mitigate magnetic field interference by adjusting the emission direction and intensity.

[0150] The external disturbance buffer zone is confined to the magnetic field shielding area, ensuring that the risk of external disturbance within the buffer zone can be effectively managed through dynamic adjustment of the shielding unit.

[0151] If the buffer zone exceeds the shielded area, the shielding unit's intervention effect on the buffer zone will be greatly reduced, making it difficult to implement the shielding strategy.

[0152] For any external disturbance buffer, select 10 planar locations on the buffer and obtain the magnetic field data change at each location. Calculate the mean value and record the result as the mean magnetic field change. ;

[0153] When a moving region is detected in the external disturbance buffer:

[0154] Obtain the movement trajectory of the center of the moving region over time. The position of the center of the circle at time point is recorded as the starting position (18.4). The position of the center of the circle at time point is recorded as the termination position (20, 6);

[0155] Establish a direction vector from the starting position to the ending position. ;

[0156] Establish normal vectors pointing from the four boundaries of the examination room to the critical edge of the external disturbance. ;

[0157] Calculate the angle between the direction vector and the normal vector. , arccos(0.707) = ,in, For dot product, For the module length;

[0158] Calculate the included angles of all moving regions, assuming that the included angles of all moving regions are equal. Calculate the mean of the included angles, and record the result as the average included angle. ;

[0159] Calculate the external disturbance risk value of the external disturbance buffer. , ,in, The weights are the average values ​​of the magnetic field changes. The weight is the average value of the included angle.

[0160] The external disturbance buffer is rectangular;

[0161] Obtain the two magnetic field shielding units adjacent to the external disturbance buffer, and name them Unit 1 and Unit 2;

[0162] A two-level shielding and coordinated coverage strategy is implemented. The shielding strength of Unit 1 is adjusted based on the external interference risk value of the external interference buffer zone. The transmission directions of Unit 1 and Unit 2 are also adjusted to shield the external interference buffer zone, including:

[0163] normal vector along the outer disturbance buffer Two adjacent magnetic field shielding units were obtained in sequence and named Unit 1 and Unit 2 in order of distance from the external disturbance buffer zone from near to far.

[0164] The reason for using Unit 1 and Unit 2 is that the main source of interference comes from outside the examination room. The external units can effectively block and weaken external interference signals, maintain a stable magnetic field environment inside the examination room, and avoid frequent internal adjustments that could disrupt the examination order. The external units work together to form a magnetic field barrier, ensuring the safety and cleanliness of the electromagnetic environment inside the examination room. External installation also makes it easier to dynamically adjust, manage, and maintain the shielding system.

[0165] Obtain the initial shielding strength of unit 1 ;

[0166] Obtain the external disturbance risk value of the external disturbance buffer. ;

[0167] Calculate the shielding strength of the final adjustment unit 1 , ,in, The adjustment coefficient reflects the degree of influence of the external disturbance risk value on the shielding strength of element one.

[0168] The emission direction of the magnetic field shielding device is along the axis of the magnetic field shielding area;

[0169] Adjust the emission direction of Unit 1 so that the axis of the magnetic field shielding area corresponding to Unit 1 is connected to the center point of the external disturbance buffer.

[0170] The planar location points on the external disturbance buffer where the binary function is 1 are denoted as disturbance points, including:

[0171] Obtain the coordinates of all perturbation points in a two-dimensional coordinate system, calculate the mean of the horizontal axis coordinates and the mean of the vertical axis coordinates, and obtain the coordinates of the global center point. ;

[0172] For arbitrary external disturbance buffers:

[0173] The coordinates of the partition center point are obtained by calculating the mean of the x and y coordinates of the disturbance points on the external disturbance buffer. ;

[0174] Existing techniques for calculating the Euclidean distance from the partition center point to the global center point:

[0175] ;

[0176] Update the coordinates of the center point of the outer disturbance buffer partition to [value]. , ,in, Used to control the decay rate;

[0177] Let be a decreasing function, representing the Euclidean distance. The smaller the value, the smaller the adjustment range of the partition center point, and the Euclidean distance. The larger the value, the greater the adjustment range of the partition center point;

[0178] Adjust the emission direction of Unit 2 so that the axis of the magnetic field shielding area corresponding to Unit 2 is connected to the center point of the corresponding external disturbance buffer zone.

[0179] The coverage area of ​​a single magnetic field shielding unit is limited, and its magnetic field shielding area is usually conical or other finite spatial shapes. The shielding strength decreases with distance and directional angle. Unit one may only cover a part of the external disturbance buffer or the coverage may not be uniform enough, so unit two is needed to enhance the coverage.

[0180] Example 2, refer to Figure 2 A microwave magnetic field measurement system, comprising:

[0181] The magnetic field shielding unit deployment module is used to install multiple magnetic field shielding units on the roof of each floor, set the emission direction, and calculate the coverage radius according to the floor height to achieve basic deployment of magnetic field shielding for the entire floor.

[0182] The magnetic field data mapping module is used to collect three-dimensional spatial magnetic field data from multiple magnetic field sensors within the floor and map it into two-dimensional planar magnetic field data according to the floor height.

[0183] The magnetic field change difference differentiation module is used to calculate the change in magnetic field data at planar location points in real time, and to differentiate between personnel movement and communication equipment interference based on binary functions and movement area determination strategies.

[0184] The external disturbance buffer risk assessment module is used to divide the external disturbance critical edge into external disturbance buffer zones according to the magnetic field shielding area, and calculate the external disturbance risk value based on the angle between the average magnetic field change and the direction of movement.

[0185] The secondary shielding coordination adjustment module is used to adjust the shielding strength and emission direction of adjacent magnetic field shielding units according to the external disturbance risk value. Combined with the decreasing adjustment strategy of the global center point and the partition center point, it realizes the dynamic shielding optimization of the external disturbance buffer.

[0186] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus.

[0187] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A microwave magnetic field measurement method, characterized in that, include: Multiple magnetic field shielding units are installed on the roof of each floor to shield the magnetic field, and the magnetic field shielding units can adjust the emission direction. Establish a two-dimensional coordinate system by selecting any point on the floor as the origin; Multiple magnetic field sensors are deployed in the floor to collect three-dimensional spatial magnetic field data, and the three-dimensional spatial magnetic field data is mapped into two-dimensional planar magnetic field data according to the floor height. Filter any exam room currently holding an exam on this floor based on the exam schedule; Implement a strategy to differentiate magnetic field changes, collect and calculate the changes in magnetic field data at planar locations in the examination room in real time, and use this data to distinguish between personnel movement and interference from communication equipment. An alarm will be triggered if interference from communication devices is detected in the examination room. Set an external disturbance critical distance, and expand the preset external disturbance critical distance outward based on the four boundaries of the examination room to form an external disturbance critical edge around the examination room. Implement an external disturbance buffer shielding strategy, divide the external disturbance critical edge according to the magnetic field shielding area and define the external disturbance buffer, and calculate the external disturbance risk value based on the change in magnetic field data and personnel movement trajectory; The external disturbance buffer is rectangular; Obtain the two magnetic field shielding units adjacent to the external disturbance buffer, and name them Unit 1 and Unit 2; A two-level shielding and coordinated coverage strategy is implemented. The shielding strength of Unit 1 is adjusted according to the external interference risk value of the external interference buffer, and the transmission directions of Unit 1 and Unit 2 are adjusted to shield the external interference buffer.

2. The microwave magnetic field measurement method according to claim 1, characterized in that, The installation of multiple magnetic field shielding units on the roof of each floor for shielding the emitted magnetic field area includes: The magnetic field shielding region is conical in space, with the apex of the magnetic field shielding region located at the magnetic field shielding unit, and the emission angle being half the apex angle of the cone; The specific steps for calculating the number of magnetic field shielding units to be installed on any floor are as follows: The emission angle of the fixed magnetic field shielding unit is ; Get floor height ; Calculate the coverage radius of the magnetic field shielding area on the floor. , ; The magnetic field shielding area is circular on the floor surface. Calculate the area of ​​the square inscribed in the circular shape. , ,in, Let be the side length of the inscribed square; Get the floor area of ​​the building ; calculate ,in, The number of magnetic field shielding units to be installed; The floor area is divided into multiple grids with side lengths of... A square is formed, and the midpoint of each square is vertically mapped onto the rooftop for installing the magnetic field shielding unit.

3. The microwave magnetic field measurement method according to claim 2, characterized in that, The process of mapping three-dimensional spatial magnetic field data into two-dimensional planar magnetic field data based on floor height includes: A three-dimensional coordinate system is obtained by establishing a vertically upward z-axis at the origin of the two-dimensional coordinate system; The spatial position point measured by the magnetic field sensor at time t is obtained as follows. Three-dimensional spatial magnetic field data ,in, This represents the coordinates of a point in a three-dimensional coordinate system. The magnetic field data is in vector form; Three-dimensional spatial magnetic field data of spatial locations at different heights on the same z-axis are obtained in a three-dimensional coordinate system, and the three-dimensional spatial magnetic field data are mapped to the z-axis to obtain... ; The two-dimensional planar magnetic field data are obtained by weighted averaging all mapped three-dimensional spatial magnetic field data along the z-axis. ; ,in, The weights of spatial location points, This represents the coordinates of a spatial point mapped to a two-dimensional coordinate system.

4. The microwave magnetic field measurement method according to claim 3, characterized in that, The strategy for distinguishing differences in magnetic field changes involves real-time collection and calculation of magnetic field data changes at planar locations within the examination room. This data is used to differentiate between personnel movement and interference from communication equipment, including: Regarding the floor plan location of the examination room: Calculate the planar position point Magnetic field data change ; ,in, Here are the two-dimensional planar magnetic field data at time t. for Two-dimensional planar magnetic field data at time t. For time step; Set the threshold for magnetic field change ; Set planar position point binary functions , among which, when hour, ,when , ; A movement region is defined, which represents a circular planar region of the magnetic field disturbed by the movement of personnel, and simultaneously contains multiple planar position points with the same binary function. The number of planar location points contained in the moving area is denoted as . ; The number of planar locations in a moving region where the value of a binary function is simultaneously equal to 1 is denoted as . ; Set quantity ratio threshold ; like If so, it is determined that the moving region simultaneously contains multiple planar position points with the same binary function; The center of the moving area represents the movement trajectory of the personnel over time; Check if there is a moving area in the two-dimensional coordinate system where the examination room is located; If a movement area exists, the change in the magnetic field within the examination room is determined to be caused by the movement of people. If no movement region exists, then determine the time step at multiple time steps. Does there exist planar location points within the area that satisfy the condition that the change in magnetic field data is greater than or equal to the threshold of magnetic field change? If the aforementioned planar location point exists, it is determined that the change in the magnetic field within the examination room is due to interference from communication equipment.

5. The microwave magnetic field measurement method according to claim 1, characterized in that, The external disturbance buffer shielding strategy involves dividing the external disturbance critical edge according to the magnetic field shielding area and defining the external disturbance buffer. It calculates the external disturbance risk value based on changes in magnetic field data and personnel movement trajectories, including: The area between the critical edge of the external disturbance and the boundaries of the examination room is divided into multiple external disturbance buffer zones according to the magnetic field shielding area in which it is located. For any external disturbance buffer, select multiple planar locations on the buffer and obtain the magnetic field data change at each location. Calculate the mean value, and record the result as the mean magnetic field change. ; When a moving region is detected in the external disturbance buffer: Obtain the movement trajectory of the center of the moving region over time. The position of the center of the circle at any given time is recorded as the starting position. The position of the center of the circle at any given moment is recorded as the ending position; Establish a direction vector from the starting position to the ending position. ; Establish normal vectors pointing from the four boundaries of the examination room to the critical edge of the external disturbance. ; Calculate the angle between the direction vector and the normal vector. , ,in, For dot product, For the module length; Obtain the included angles of all moving areas, calculate the mean of the included angles, and record the result as the average included angle. ; Calculate the external disturbance risk value of the external disturbance buffer. , ,in, The weights are the average values ​​of the magnetic field changes. The weight is the average value of the included angle.

6. The microwave magnetic field measurement method according to claim 5, characterized in that, The implementation of the secondary shielding collaborative coverage strategy, which adjusts the shielding strength of unit one according to the external disturbance risk value of the external disturbance buffer, includes: normal vector along the outer disturbance buffer Two adjacent magnetic field shielding units were obtained in sequence and named Unit 1 and Unit 2 in order of distance from the external disturbance buffer zone from near to far. Obtain the initial shielding strength of unit 1 ; Obtain the external disturbance risk value of the external disturbance buffer. ; Calculate the shielding strength of the final adjustment unit 1 , ,in, The adjustment coefficient reflects the degree of influence of the external disturbance risk value on the shielding strength of element one.

7. The microwave magnetic field measurement method according to claim 6, characterized in that, The method of adjusting the transmission directions of unit one and unit two for shielding external interference buffers includes: The emission direction of the magnetic field shielding device is along the axis of the magnetic field shielding area; Adjust the emission direction of Unit 1 so that the axis of the magnetic field shielding area corresponding to Unit 1 is connected to the center point of the external disturbance buffer. The planar location point on the external disturbance buffer where the binary function is 1 is denoted as the disturbance point; Obtain the coordinates of all perturbation points in a two-dimensional coordinate system, calculate the mean of the horizontal axis coordinates and the mean of the vertical axis coordinates, and obtain the coordinates of the global center point. ; For arbitrary external disturbance buffers: The coordinates of the partition center point are obtained by calculating the mean of the x and y coordinates of the disturbance points on the external disturbance buffer. ; Calculate the Euclidean distance from the partition center point to the global center point. ; Update the coordinates of the center point of the outer disturbance buffer partition to [value]. , ,in, Used to control the decay rate; Let be a decreasing function, representing the Euclidean distance. The smaller the value, the smaller the adjustment range of the partition center point, and the Euclidean distance. The larger the value, the greater the adjustment range of the partition center point; Adjust the emission direction of Unit 2 so that the axis of the magnetic field shielding area corresponding to Unit 2 is connected to the center point of the partition.

8. A microwave magnetic field measurement system, applied to the microwave magnetic field measurement method according to claims 1-7, characterized in that, include: The magnetic field shielding unit deployment module is used to install multiple magnetic field shielding units on the roof of each floor, set the emission direction, and calculate the coverage radius according to the floor height to achieve basic deployment of magnetic field shielding for the entire floor. The magnetic field data mapping module is used to collect three-dimensional spatial magnetic field data from multiple magnetic field sensors within the floor and map it into two-dimensional planar magnetic field data according to the floor height. The magnetic field change difference differentiation module is used to calculate the change in magnetic field data at planar location points in real time, and to differentiate between personnel movement and communication equipment interference based on binary functions and movement area determination strategies. The external disturbance buffer risk assessment module is used to divide the external disturbance critical edge into external disturbance buffer zones according to the magnetic field shielding area, and calculate the external disturbance risk value based on the angle between the average magnetic field change and the direction of movement. The secondary shielding coordination adjustment module is used to adjust the shielding strength and emission direction of adjacent magnetic field shielding units according to the external disturbance risk value, combined with the decreasing adjustment strategy of the global center point and the regional center point.

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