RFID-Based Indoor Positioning Method for Enterprise Personnel

Abstract

The present invention discloses an indoor positioning method for enterprise personnel based on RFID. The specific steps include: collecting precise positioning information for indoor positioning and obtaining a first accuracy coefficient according to the precise positioning information; collecting signal status information for signal delay detection and obtaining a second accuracy coefficient according to the signal status information; establishing a multi-point verification model based on the first accuracy coefficient and the second accuracy coefficient; using the multi-point cross method to verify the balance of positioning signals; performing manual intervention operations according to the verification results of the balance of positioning signals; fusing the methods based on signal strength and arrival angle to improve the accuracy and real-time performance of indoor positioning for enterprise personnel; comprehensively evaluating the indoor positioning results of enterprise personnel by establishing a multi-point verification model, avoiding the problems of low efficiency and narrow coverage of manual management, providing an effective indoor positioning means for large-scale intelligent park management, and avoiding the imbalance problem of indoor positioning accuracy and efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of Internet of Things, and more specifically, the present invention is an indoor positioning method for enterprise personnel based on RFID. Background Art

[0002] Among the existing indoor positioning methods for enterprise personnel based on RFID, the method based on signal strength positioning was developed earliest, but the positioning accuracy of the method based on signal strength positioning is relatively low, and it is greatly affected by the environment and is not suitable for precise positioning inside large factory areas. The method based on time difference positioning has better positioning accuracy, but requires a high-precision time synchronization system and high hardware costs. The method based on angle of arrival positioning depends on complex signal processing algorithms, and the algorithm processing time may affect the delay performance of the positioning signal. In the indoor positioning of enterprise personnel in large intelligent factory areas, the delay performance of the positioning signal is more important than the absolute positioning accuracy. Excessive backhaul delay of the positioning signal will lead to delays and chaos in the internal personnel management of the enterprise. Therefore, it has become an urgent problem to evaluate the balance between positioning accuracy and signal delay.

[0003] To solve the above defects, a technical solution is now proposed. Summary of the Invention

[0004] The purpose of the present invention is to provide an indoor positioning method for enterprise personnel based on RFID to solve the deficiencies in the background art.

[0005] To achieve the above purpose, the present invention provides the following technical solution: An indoor positioning method for enterprise personnel based on RFID, the specific steps include:

[0006] Collect precise positioning information for indoor positioning, and obtain the first accuracy coefficient according to the precise positioning information;

[0007] Collect signal status information for signal delay detection, and obtain the second accuracy coefficient according to the signal status information;

[0008] Establish a multi-point verification model according to the first accuracy coefficient and the second accuracy coefficient, and use the multi-point cross method to verify the balance of the positioning signal;

[0009] Perform manual intervention operations according to the verification result of the balance of the positioning signal.

[0010] Preferably, the method for obtaining precise positioning information is:

[0011] Obtain the signal strengths received by multiple RFID readers from the tag respectively within the cycle time T, integrate the signal strengths received by multiple RFID readers from the tag respectively within the cycle time T into a data set, and mark the data set as P r ={pr i}, where i = {1, 2, 3, …, z} is the index of the RFID reader, and z is a positive integer, pr i represents the signal strength of the tag received by the i-th RFID reader. Calculate the average value of the signal strengths of the tags received by multiple RFID readers within the calculation period T. The calculation expression is The average value SS of the signal strengths of the tags received by multiple RFID readers within the period T i is the precise positioning information.

[0012] Preferably, the specific method for obtaining the first precision coefficient based on the precise positioning information is as follows:

[0013] Based on the average value SS of the signal strengths of the tags received by multiple RFID readers within the period T i calculate the preliminary positioning parameters. The calculation expression is In the formula, P s is the transmission power, v is the path loss exponent and v is a positive number, and C is a constant related to the environment;

[0014] Measure the angle of arrival of the tag signal through the reader based on the antenna array. Mark the reader coordinates as (x i , y i ), and the coordinates of the tag are (x, y). Then the angle of arrival is In the formula, θ i is the angle of arrival. Construct an equation system for the measurement results of multiple readers and calculate the angular tag coordinates in combination with the preliminary positioning parameters. The expression of the angular tag coordinates is

[0015] Use the moving average method to calculate the smoothed coordinates within the period T. Set the size of the moving window to k. Then, for each time point t within the time period T, calculate the average position of k coordinate points as (x avg (t), y avg (t)), where and Calculate the first precision coefficient through the smoothed coordinates and the angular tag coordinates. The calculation expression is F pc = |x avg (t) - x| * |y avg (t) - y|.

[0016] Preferably, the method for obtaining the signal status information is as follows:

[0017] Obtain the transmission time of the positioning signal from the tag to each RFID reader within the period T, and integrate the transmission times of the positioning signal from the tag to each RFID reader within the period T into a data set, and mark the data set as Trt = {tr i}, where i = {1, 2, 3, …, z} is the index of the RFID reader, and z is a positive integer, and tr i is the signal status information representing the transmission time of the i-th RFID reader.

[0018] Preferably, the method for obtaining the second precision coefficient according to the signal status information is:

[0019] Mark the transmission delay of the RFID reader receiving the tag signal as Δt i = tr i - t re , where t re is the time when the RFID reader receives the tag signal. According to the known position information of the RFID reader, there is D i = c * tr i , where D i is the distance from the tag to the RFID reader, c is the propagation speed of the RF signal. Mark one RFID reader as the reference RFID reader, and the distance between the reference RFID reader and the tag is D1. Then the difference coefficient between the signal transmission delays of each RFID reader and the reference RFID reader is Then the calculation expression of the second precision coefficient is

[0020] Preferably, the method for establishing the multi-point verification model is:

[0021] The mathematical model of the multi-point verification model is where P s is the transmission power, z is the total number of RFID readers, M pv is the balance offset index. Preset the first balance offset threshold M t1 and the second balance offset threshold M t2 , and the first balance offset threshold M t1 is less than the second balance offset threshold M t2 . Compare the balance offset index M pv with the first balance offset threshold M t1 and the second balance offset threshold M t2 . If the balance offset index M pv is less than or equal to the first balance offset threshold M t1 , then mark that the multi-point verification of the indoor positioning coordinates passes;

[0022] If the first balance offset threshold M t1 is less than the balance offset index M pv and less than the second balance offset threshold M t2 , then mark that the multi-point verification of the indoor positioning coordinates is in doubt;

[0023] If the balance offset index M pv is greater than or equal to the second balance offset threshold M t2 , then mark the multi-point verification error of the indoor positioning coordinates.

[0024] Preferably, the logic for manual intervention operation is as follows:

[0025] When the multi-point verification of the indoor positioning coordinates passes, the indoor positioning of enterprise personnel is accurate and timely, and there is no need to transmit it to the management personnel;

[0026] When the multi-point verification of the indoor positioning coordinates is in doubt, the indoor positioning of enterprise personnel is inaccurate or untimely. After recording the indoor positioning coordinates, notify the management personnel for manual review;

[0027] When the multi-point verification of the indoor positioning coordinates is incorrect, the indoor positioning of enterprise personnel is inaccurate and untimely. After recording the indoor positioning coordinates, prompt the management personnel to intervene and control.

[0028] In the above technical solution, the technical effects and advantages provided by the present invention are as follows:

[0029] By integrating the technical methods based on signal strength and arrival angle, the present application improves the accuracy and real-time performance of indoor positioning of enterprise personnel, conducts a balance test on the accuracy and delay state of indoor positioning, establishes a multi-point verification model, and uses multiple RFID devices to comprehensively evaluate the indoor positioning results of enterprise personnel, verifies the accuracy and real-time performance of indoor positioning, further improves the reliability level of indoor positioning, avoids the problems of low efficiency and narrow coverage of manual management, provides an effective indoor positioning means for large-scale intelligent park management, and avoids the imbalance problem of indoor positioning accuracy and efficiency. Description of the Drawings

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required in the embodiments. Obviously, the drawings in the following description are only some embodiments recorded in the present invention. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings.

[0031] Figure 1 It is the method flow chart of the present invention. Detailed Embodiments

[0032] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0033] Embodiment 1: Please refer to Figure 1 As shown, the present invention is an indoor positioning method for enterprise personnel based on RFID, and the specific steps include:

[0034] Collect accurate positioning information for indoor positioning, and obtain the first accuracy coefficient according to the accurate positioning information;

[0035] Collect signal status information for signal delay detection, and obtain the second accuracy coefficient according to the signal status information;

[0036] Establish a multi-point verification model according to the first accuracy coefficient and the second accuracy coefficient, and use the multi-point cross method to verify the balance of the positioning signal;

[0037] Perform manual intervention operations according to the verification result of the balance of the positioning signal.

[0038] In the security management of large-scale intelligent factory areas, the indoor positioning method for enterprise personnel has certain requirements for positioning accuracy and signal delay:

[0039] The accuracy requirement is generally at the meter level to ensure accurate tracking of the real-time location of personnel. In high-risk areas, such as dangerous chemical storage areas, the positioning accuracy requirement is sub-meter level, and in office areas or public areas, a meter-level accuracy is required;

[0040] The signal transmission delay requirement is at the millisecond level to ensure the real-time response of the system. For a safety warning system that requires immediate response, the lower the delay, the better. In a real-time monitoring system, too high a signal delay will affect the system response speed;

[0041] If the accuracy of indoor positioning is too low, the following adverse consequences will occur:

[0042] It is impossible to accurately locate the personnel working in high-risk areas, increasing the possibility of accidents. In case of an emergency, it is impossible to quickly find the personnel who need to evacuate, which may lead to casualties;

[0043] It is difficult to monitor personnel flow and activities, resulting in unreasonable resource scheduling. Security personnel cannot quickly locate and handle suspicious activities, increasing potential safety hazards;

[0044] If the delay of the positioning signal is too high, the following adverse consequences will occur:

[0045] During a security incident or emergency, delays in information transmission and response can lead to extended processing times, increased losses, failure of the security warning system to trigger in a timely manner, and missed optimal response opportunities.

[0046] Excessively high signal delays may cause data inconsistencies in the system, affecting the overall monitoring effect. The decline in the real-time nature of positioning information results in the management layer being unable to obtain the latest personnel dynamics.

[0047] Collect precise positioning information for indoor positioning and obtain the first accuracy coefficient based on the precise positioning information.

[0048] The method for obtaining precise positioning information is as follows:

[0049] Obtain the signal strengths received by multiple RFID readers from tags respectively within the cycle time T, integrate the signal strengths received by multiple RFID readers from tags respectively within the cycle time T into a data set, and mark the data set as P r ={pr i}, where i = {1, 2, 3, …, z} is the index of the RFID reader, and z is a positive integer. pr i represents the signal strength received by the i-th RFID reader from the tag. Calculate the average value of the signal strengths received by multiple RFID readers from tags respectively within the cycle time T. The calculation expression is The average value SS of the signal strengths received by multiple RFID readers from tags respectively within the cycle time T i is the precise positioning information.

[0050] The specific method for obtaining the first accuracy coefficient based on the precise positioning information is as follows:

[0051] Based on the average value SS of the signal strengths received by multiple RFID readers from tags respectively within the cycle time T i Calculate the preliminary positioning parameters. The calculation expression is In the formula, P s is the transmission power, v is the path loss exponent and v is a positive number, and C is a constant related to the environment.

[0052] Measure the angle of arrival of the tag signal through a reader based on an antenna array. Mark the reader coordinates as (x i , y i ), and the coordinates of the tag are (x, y). Then the angle of arrival is In the formula, θ i is the angle of arrival. Construct a system of equations for the measurement results of multiple readers and calculate the angular tag coordinates in combination with the preliminary positioning parameters. The expression for the angular tag coordinates is

[0053] The smoothed coordinates within the cycle time T are calculated using the moving average method. Assuming the size of the moving window is k, for each time point t within the time cycle T, the average position of k coordinate points is calculated as (x avg (t), y avg (t)), where and The first precision coefficient is calculated through the smoothed coordinates and the angle label coordinates. The calculation expression is F pc = |x avg (t) - x| * |y avg (t) - y|.

[0054] In this application, the approximate position of the target is quickly estimated by measuring the received signal strength, and then the preliminary positioning result is corrected by measuring the angle of signal arrival, thus significantly improving the positioning accuracy;

[0055] The measurement based on signal strength is greatly affected by environmental factors, while the measurement based on angle of arrival provides more positioning information in complex environments, enhancing the adaptability of signal positioning to interference and occlusion. At the same time, combining two different positioning methods reduces the limitations of a single method, ensuring good positioning performance under different conditions;

[0056] The preliminary position of the signal is quickly obtained through the measurement based on signal strength and is corrected in real time through the measurement based on angle of arrival, ensuring that the signal positioning can quickly respond to changes in a dynamic environment and improving the real-time performance of security management. In case of an emergency, quick and accurate positioning helps managers take timely actions and reduce potential losses;

[0057] In terms of application cost, the hardware used for the measurement based on signal strength is relatively simple. Combining the measurement based on signal strength with the measurement based on angle of arrival can improve the positioning accuracy without adding too much cost;

[0058] The preliminary precise positioning method that combines the positioning based on signal strength with the positioning based on angle of arrival not only improves the positioning accuracy and robustness but also optimizes the real-time response ability to meet the requirements of complex application scenarios. Through this combined positioning method, enterprises can achieve intelligent and efficient security management, ensure the safety of personnel and assets, and at the same time reduce costs and risks.

[0059] Collect the signal status information for signal delay detection and obtain the second precision coefficient according to the signal status information;

[0060] The method for obtaining the signal status information is as follows:

[0061] Obtain the transmission time of the positioning signal from the tag to each RFID reader within the cycle time T, integrate the transmission times of the positioning signal from the tag to each RFID reader within the cycle time T into a data set, and label the data set as T rt ={tr i}, where i = {1, 2, 3, …, z} is the index of the RFID reader, and z is a positive integer, and tr i is the signal status information representing the transmission time of the i-th RFID reader;

[0062] The method for obtaining the second precision coefficient according to the signal status information is as follows:

[0063] Mark the transmission delay of the RFID reader receiving the tag signal as Δt i = tr i - t re , where t re is the time when the RFID reader receives the tag signal. According to the known position information of the RFID reader, there is D i = c * tr i , where D i is the distance from the tag to the RFID reader, c is the propagation speed of the RF signal. Mark one RFID reader as the reference RFID reader, and the distance between the reference RFID reader and the tag is D1. Then the difference coefficient between the signal transmission delays of each RFID reader and the reference RFID reader is Then the calculation expression of the second precision coefficient is

[0064] Provide accurate positioning information by calculating the time difference of the signal arriving at each RFID reader, and reduce the influence of the multipath effect by using the time difference instead of the absolute time to improve the positioning accuracy;

[0065] Improve the robustness to environmental changes and signal interference by calculating the second precision coefficient, strengthen the adaptability, so as to provide a stable positioning effect in a complex environment, and effectively reduce the impact of the failure or invalidation of a single RFID reader on the overall positioning accuracy through the collaborative work of multiple RFID readers;

[0066] Achieve real-time positioning and monitoring by quickly processing the signal arrival time, so as to adapt to the dynamically changing application scenarios. Evaluating the signal delay not only helps with positioning, but also can analyze the quality and stability of signal propagation to ensure the overall efficiency of the system;

[0067] Evaluate the transmission delay degree of the tag positioning signal through the second precision coefficient, which not only improves the positioning accuracy and system robustness, but also realizes fast response and real-time monitoring, has important application value in the field of intelligent security, and improves the overall efficiency and security.

[0068] Establish a multi - point verification model based on the first precision coefficient and the second precision coefficient, and use the multi - point crossover method to verify the balance of the positioning signal;

[0069] The method for establishing the multi - point verification model is as follows:

[0070] The mathematical model of the multi - point verification model is In the formula, P s is the transmission power, z is the total number of RFID readers, M pv is the balance offset index, a first balance offset threshold M t1 and a second balance offset threshold M t2 are preset, and the first balance offset threshold M t1 is less than the second balance offset threshold M t2 . Compare the balance offset index M pv with the first balance offset threshold M t1 and the second balance offset threshold M t2 . If the balance offset index M pv is less than or equal to the first balance offset threshold M t1 , it is marked that the multi - point verification of the indoor positioning coordinates passes;

[0071] If the first balance offset threshold M t1 is less than the balance offset index M pv which is less than the second balance offset threshold M t2 , it is marked that the multi - point verification of the indoor positioning coordinates is in doubt;

[0072] If the balance offset index M pv is greater than or equal to the second balance offset threshold M t2 , it is marked that the multi - point verification of the indoor positioning coordinates is incorrect.

[0073] Perform manual intervention operations according to the verification result of the balance of the positioning signal;

[0074] When the multi - point verification of the indoor positioning coordinates passes, the indoor positioning of enterprise personnel is accurate and timely, and there is no need to transmit it to the management personnel;

[0075] When the multi - point verification of the indoor positioning coordinates is in doubt, the indoor positioning of enterprise personnel is inaccurate or untimely. Record the indoor positioning coordinates and notify the management personnel for manual review;

[0076] When the multi - point verification of the indoor positioning coordinates is incorrect, the indoor positioning of enterprise personnel is inaccurate and untimely. Record the indoor positioning coordinates and prompt the management personnel to intervene and control.

[0077] By integrating the technical methods based on signal strength and angle of arrival, this application improves the accuracy and real-time performance of indoor positioning for enterprise personnel, conducts a balance test on the accuracy and latency status of indoor positioning, establishes a multi-point verification model, and comprehensively evaluates the indoor positioning results of enterprise personnel using multiple RFID devices to verify the accuracy and real-time performance of indoor positioning, further improving the reliability level of indoor positioning, avoiding the problems of low efficiency and narrow coverage of manual management, providing an effective indoor positioning means for large-scale intelligent park management, and avoiding the imbalance between indoor positioning accuracy and efficiency.

[0078] The above formulas are all dimensionless and take their numerical values for calculation. The formulas are obtained by collecting a large amount of data for software simulation to get a formula closest to the actual situation. The preset parameters in the formulas are set by those skilled in the art according to the actual situation.

[0079] The above embodiments can be implemented in whole or in part by software, hardware, firmware, or any other combination. When implemented using software, the above embodiments can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions or computer programs. When the computer instructions or computer programs are loaded or executed on a computer, the processes or functions described in the embodiments of this application are generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center in a wired or wireless (such as infrared, wireless, microwave, etc.) manner. The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server or data center that contains one or more collections of available media. The available medium can be a magnetic medium (such as a floppy disk, hard disk, magnetic tape), an optical medium (such as a DVD), or a semiconductor medium. The semiconductor medium can be a solid-state drive.

[0080] It should be understood that in various embodiments of this application, the magnitudes of the sequence numbers of the above processes do not mean the order of execution. The order of execution of each process should be determined by its function and internal logic, and should not constitute any limitation to the implementation process of the embodiments of this application.

[0081] Those of ordinary skill in the art can realize that the units and algorithm steps of each example described in combination with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are executed in a hardware or software manner depends on the specific application and design constraints of the technical solution. A professional technician can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of this application.

[0082] Those skilled in the art can clearly understand that for the convenience and brevity of description, the specific working process of the system described above can refer to the corresponding process in the foregoing method embodiments, and will not be described herein again.

[0083] If the described functions are implemented in the form of software function units and sold or used as independent goods, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a part of this technical solution, can be embodied in the form of software goods. This computer software goods is stored in a storage medium, including several instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of this application. The foregoing storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical discs that can store program codes.

[0084] The above is only the specific implementation manner of this application, but the protection scope of this application is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed in this application, and all should be covered by the protection scope of this application. Therefore, the protection scope of this application should be subject to the protection scope of the claimed rights.

Claims

1. An indoor positioning method for enterprise personnel based on RFID, characterized in that, The specific steps include: Collect precise positioning information for indoor positioning, and obtain the first accuracy coefficient according to the precise positioning information; Collect signal status information for signal delay detection, and obtain the second accuracy coefficient according to the signal status information; Establish a multi-point verification model based on the first accuracy coefficient and the second accuracy coefficient, and use the multi-point cross method to verify the balance of the positioning signal; Perform manual intervention operations according to the verification result of the balance of the positioning signal; The method for establishing the multi-point verification model is: The mathematical model of the multi-point verification model is In the formula, P s is the transmission power, z is the total number of RFID readers, M pv is the balance offset index, and the preset first balance offset threshold M t1 and the second balance offset threshold M t2 are set. And the first balance offset threshold M t1 is less than the second balance offset threshold M t2 . Compare the balance offset index M pv with the first balance offset threshold M t1 and the second balance offset threshold M t2 . If the balance offset index M pv is less than or equal to the first balance offset threshold M t1 , it means that the multi-point verification of the indoor positioning coordinates passes; If the first balance offset threshold M t1 is less than the balance offset index M pv and less than the second balance offset threshold M t2 , then the multi-point verification of the indoor positioning coordinates is marked as doubtful; If the balance offset index M pv is greater than or equal to the second balance offset threshold M t2 , then mark the multi-point verification error of the indoor positioning coordinates.

2. The indoor positioning method for enterprise personnel based on RFID according to claim 1, characterized in that The method for obtaining the precise positioning information is: Obtain the signal strengths received by multiple RFID readers from the tag respectively within the cycle time T, integrate the signal strengths received by multiple RFID readers from the tag respectively within the cycle time T into a data set, and label the data set as P r ={pr i}, where i = {1, 2, 3, …, z} is the index of the RFID reader, and z is a positive integer, and pr i represents the signal strength received by the i-th RFID reader from the tag. Calculate the average value of the signal strengths received by multiple RFID readers from the tag respectively within the cycle time T. The calculation expression is The average value SS of the signal strengths received by multiple RFID readers from the tag respectively within the cycle time T i is the precise positioning information.

3. The indoor positioning method for enterprise personnel based on RFID according to claim 2, characterized in that, The specific method for obtaining the first accuracy coefficient according to the precise positioning information is: Based on the average signal strength SS received by multiple RFID readers from tags within the cycle time T i Calculate the preliminary positioning parameters, and the calculation expression is In the formula, P s is the transmission power, v is the path loss exponent and v is a positive number, and C is a constant related to the environment; By measuring the angle of arrival of the tag signal with an antenna array-based reader, marking the reader coordinates as (x i , y i ), and the coordinates of the tag as (x, y), the angle of arrival is then In the formula, θ i is the angle of arrival. An equation system is constructed from the measurement results of multiple readers and combined with the preliminary positioning parameters to calculate the angular tag coordinates. The expression for the angular tag coordinates is Calculate the smoothed coordinates within the period time T using the moving average method. Set the moving window size as k. Then, for each time point t within the time period T, calculate the average position of k coordinate points as (x avg (t), y avg (t)), where and Calculate the first precision coefficient by using the smoothed coordinates and the angle label coordinates. The calculation expression is F pc = |x avg (t) - x| * |y avg (t) - y|.

4. The indoor positioning method for enterprise personnel based on RFID according to claim 1, wherein The method for obtaining the signal status information is: Obtain the transmission time of the positioning signal from the tag to each RFID reader within the cycle time T, integrate the transmission times of the positioning signal from the tag to each RFID reader within the cycle time T into a data set, and label the data set as T rt ={tr i}, where i = {1, 2, 3, …, z} is the index of the RFID reader, and z is a positive integer, and tr i is the signal status information representing the transmission time of the i-th RFID reader.

5. The indoor positioning method for enterprise personnel based on RFID according to claim 4, characterized in that, The method for obtaining the second accuracy coefficient according to the signal status information is: The transmission delay for the tagged RFID reader to receive the tag signal is Δt i = tr i - t re , where t re is the time when the RFID reader receives the tag signal. According to the known position information of the RFID reader, there is D i = c * tr i , where D i is the distance from the tag to the RFID reader, c is the propagation speed of the RF signal. One RFID reader is marked as the reference RFID reader, and the distance between the reference RFID reader and the tag is D1. Then the difference coefficient of the signal transmission delay of each RFID reader from the reference RFID reader is Then the calculation expression of the second precision coefficient is 6. The RFID-based indoor positioning method for enterprise personnel according to claim 5, wherein The logic for performing manual intervention operations is: When the multi-point verification of the indoor positioning coordinates passes, the indoor positioning of enterprise personnel is accurate and timely, and there is no need to transmit it to the management personnel; When the multi-point verification of the indoor positioning coordinates is in doubt, the indoor positioning of enterprise personnel is inaccurate or untimely. After recording the indoor positioning coordinates, notify the management personnel for manual recheck; When the multi-point verification of the indoor positioning coordinates is incorrect, the indoor positioning of enterprise personnel is inaccurate and untimely. After recording the indoor positioning coordinates, prompt the management personnel to intervene and control.

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