An RFID-based berth positioning system and method

Abstract

The present invention discloses a berth positioning system and method based on RFID, which relates to the technical field of berth positioning. The system includes: an electronic tag for storing the berth electronic tag number; a reader for activating the electronic tag by transmitting a radio frequency signal and reading the electronic tag number; a communication module for transmitting the electronic tag number and the number receiving time to a server; and a server for storing and processing the received electronic tag number and the number receiving time, and performing berth positioning according to the berth label correspondence table. According to the technical solution of the present application, the function of accurately matching a vehicle with a berth in a parking charging scenario can be realized, and it has high application value.

Description

Technical Field

[0001] The present invention relates to the technical field of berth positioning, and particularly relates to a berth positioning system and method based on RFID. Background Art

[0002] In recent years, with the gradual increase in the number of automobiles, cars have become an essential means of transportation for people's daily travel. The problem of difficult urban parking has become increasingly serious, especially near busy commercial areas, residential communities, and public transportation hubs. Among them, some vehicles occupy public berths for a long time, making it difficult for some car owners with temporary parking needs to find vacant berths, which has increased the road traffic pressure to a certain extent. To solve this problem, various regions have carried out intelligent transformation of the urban berth management system to improve the turnover rate of urban berths by efficiently managing berths. Among them, mobile video inspection vehicles play a crucial role in the urban berth management system. The video inspection vehicle conducts regular inspections of berths, intelligently identifies the license plate numbers of vehicles parked in the berths, and automatically generates parking orders, which significantly reduces the labor cost compared with traditional road inspections. However, the video inspection vehicle has the problem of inaccurate berth positioning during use, which is likely to cause abnormal parking orders and trigger a series of problems. Therefore, the research and development of a simple and efficient berth positioning method is imminent.

[0003] Currently, most existing berth positioning methods have defects in one aspect or another. For example, for the berth positioning method based on GPS, the GPS system adopted by this method has a large deviation in positioning data in application scenarios with obstacles, and at the same time, the implementation of this method requires the device to be able to connect to the network in real time and will fail in areas with poor network signals; for the berth positioning method based on image recognition, the application scenario of this method is relatively limited, and it requires obvious text markings on the berth. Restricted by this condition, it is difficult to carry out berth positioning work when the light conditions are poor or the berth markings are covered by obstacles. Therefore, based on this problem, the present application proposes a berth positioning system and method based on RFID. Summary of the Invention

[0004] Technical Objectives

[0005] To solve the above problems, the objective of the present invention is to provide a berth positioning system and method based on RFID, which not only solves the problem of inaccurate berth positioning in the urban berth management system, but also has a wide range of application scenarios, is not easily interfered by external factors, realizes the simplification and automation of berth positioning, improves the accuracy of berth positioning, and avoids the problem of abnormal berth number recognition caused by environmental factors.

[0006] Technical Solutions

[0007] To achieve the above object, the present invention provides an RFID-based berth positioning system and method, which activates an electronic tag on the berth by transmitting a radio frequency signal through a reader mounted on a vehicle, and matches the tag data with the berth according to a prefabricated berth tag correspondence table, thereby realizing accurate berth positioning.

[0008] In a first aspect, the present invention provides an RFID-based berth positioning system, including:

[0009] An electronic tag, used to store the berth electronic tag number, which is installed on the berth;

[0010] A reader, which activates the electronic tag by transmitting a radio frequency signal and reads the electronic tag number;

[0011] A communication module, used to transmit the electronic tag number and the number receiving time to the server;

[0012] A server, used to store and process the received electronic tag number and the number receiving time, and perform berth positioning according to the berth tag correspondence table;

[0013] Wherein the reader and the communication module are built on the vehicle.

[0014] Further, the electronic tag is installed on one side of the berth close to the vehicle driving road, and at least 1 electronic tag is equipped for each berth, which is located at 1 / 3 of the corresponding side of the berth.

[0015] Further, the electronic tag is installed on one side of the berth close to the vehicle driving road, and 2 electronic tags are equipped for each berth, which are located at 1 / 3 and 2 / 3 of the corresponding side of the berth respectively.

[0016] Further, the reader activates the electronic tag by transmitting a radio frequency signal and reads the electronic tag number specifically includes: the reader continuously transmits a radio frequency signal with a specific frequency to the outside through a built-in antenna, and the effective scanning range of the radio frequency signal is 1 / 3 of the berth length. When the vehicle travels near the berth, the electronic tag will be activated after entering the range of the radio frequency signal transmitted by the reader, and after being activated, it will transmit the stored electronic tag number data to the reader through the antenna.

[0017] Further, the reader further transmits the received electronic tag number and the timestamp when the reader receives the number data to the server through the communication module; the server stores the received data in a memory array and performs duplicate data removal processing. The duplicate data removal processing specifically means that when the server receives duplicate data, it only retains the data information received for the first time; the array elements of the memory array follow the principle of first in first out.

[0018] Further, the server performs berth positioning according to the berth relationship correspondence table. Specifically, if the latest numbered data in the memory array corresponds to the first electronic tag numbered data of the nth berth, it is determined that the current vehicle is located in the first half of the nth berth; if the latest numbered data in the memory array corresponds to the second electronic tag numbered data of the nth berth, it is determined that the current vehicle is located in the second half of the nth berth. The judgment standard for the front and rear positions of the berth follows the front and rear position sequence in which the vehicle passes through the berths with smaller numbers to those with larger numbers in sequence.

[0019] Further, after receiving the recognition result transmitted by the inspection UAV, the intelligent parking management platform pre-judges the current geographical location of the UAV. If it is judged that the current geographical location of the UAV is not within the range of the parking area, it is determined that the current vehicle has an illegal parking phenomenon; if the geographical location information conforms, the received recognition result is uploaded to the parking space database of the platform for matching. If the matching result of the license plate information and the berth information is inconsistent, it is determined that the current vehicle has occupied a parking space.

[0020] Further, after the vehicle has passed the last berth in the current berth sequence, the server regularly queries whether the reception time of the latest array element in the memory array is earlier than the current system time. If the condition is satisfied, it indicates that the numbered data in the memory array has expired. At this time, the server clears the memory array to avoid data misuse.

[0021] Further, the system adopts an RFID system anti-collision scheme based on tag grouping to avoid signal collision problems caused by multiple RFID electronic tags simultaneously entering the reader radio frequency field range due to the berth layout. It solves the signal collision problem by grouping the electronic tags and identifying the tags in the tag group in batches according to the binary tree search algorithm.

[0022] Further, the system adopts a deep belief network scheme to reduce the influence of multipath effect and wireless radio frequency signal attenuation on RFID system berth positioning. It extracts effective feature information from RFID data so that the system can better adapt to complex indoor and outdoor environments.

[0023] In a second aspect, the present invention also provides an RFID-based berth positioning method. The method is based on the system described in the first aspect above and includes:

[0024] Install an electronic tag for storing the berth number on the berth;

[0025] Formulate a correspondence table between the electronic tag and the berth according to the electronic tag layout;

[0026] Activate the electronic tag through a reader mounted on a vehicle;

[0027] The reader receives the serial number data transmitted by the electronic tag and further transmits it to the server together with the serial number reception time;

[0028] The server stores and processes the received electronic tag serial number and serial number reception time, and performs berth positioning according to the berth tag correspondence table.

[0029] Thirdly, the present invention also provides a computer-readable storage medium, in which a computer program is stored, and when the computer program is executed by a processor, the foregoing RFID-based berth positioning method is implemented.

[0030] The present invention activates the electronic tag on the berth by transmitting a radio frequency signal through a reader mounted on a vehicle, and matches the tag data with the berth according to a prefabricated berth tag correspondence table, thereby realizing accurate berth positioning; through an RFID system anti-collision scheme based on tag grouping to avoid signal collision problems caused by multiple RFID electronic tags entering the radio frequency field range of the reader simultaneously due to the berth layout; through a deep belief network scheme to reduce the influence of multipath effects and radio frequency signal attenuation on the berth positioning of the RFID system. The system and method not only solve the problem of inaccurate berth positioning in the urban berth management system, but also have a wide range of application scenarios, are not easily interfered by external factors, realize the simplification and automation of berth positioning, improve the accuracy of berth positioning, and avoid the problem of abnormal berth number recognition caused by environmental factors.

[0031] Beneficial effects

[0032] By implementing the RFID-based berth positioning system and method provided by the present invention, the following technical effects are achieved:

[0033] (1) The present invention activates the electronic tag on the berth by transmitting a radio frequency signal through a reader mounted on a vehicle, and matches the tag data with the berth according to a prefabricated berth tag correspondence table, thereby realizing accurate berth positioning; it has high adaptability to complex environments, can work effectively in a variety of application scenarios, avoids the influence of external factors on berth number recognition, and further realizes automation; the application of electronic tags enables the berth management system to record and update berth information in real time, improves the efficiency and accuracy of berth management; quickly activates the electronic tag on the berth through radio frequency signals, realizes automatic data matching, reduces the complexity of manual operations, ensures the accuracy of berth positioning, and reduces errors caused by human factors.

[0034] (2) The present invention equips 2 electronic tags on the berth and stores 3 tag data in the server memory array, and realizes more accurate positioning of the vehicle by the berth management system according to the relationship between multiple tag data and the berth; compared with equipping a single electronic tag on the berth, it can enable the berth management system to more accurately locate the specific position of the vehicle at the berth, improving the accuracy of berth positioning; by recording the tag data in the server in real time, the system has the ability to trace the cause of errors when parking orders are abnormal.

[0035] (3) The present invention adopts an anti-collision scheme for the RFID system based on tag grouping to avoid signal collision problems caused by multiple RFID electronic tags simultaneously entering the radio frequency field range of the reader due to the berth layout; by grouping the RFID tags and applying an anti-collision algorithm within each group, it reduces the signal collision problem between tags and improves the recognition efficiency of the system; by reasonably allocating communication time slots and frequency resources, it ensures that each tag group can communicate effectively within the allocated time slots.

[0036] (4) The present invention adopts a deep belief network scheme to reduce the influence of multipath effects and wireless radio frequency signal attenuation on the berth positioning of the RFID system; by extracting the RFID signal characteristics and learning the non-linear mapping relationship between the signal strength and the position information, it improves the accuracy of berth positioning; due to the deep network structure of the deep belief network, the RFID system can have good robustness and reduce the influence of multipath effects and signal attenuation on the positioning accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] To make the above-mentioned RFID-based berth positioning system and method of the present invention more obvious and understandable, the following will briefly introduce the drawings required for the specific implementation of the present invention. Obviously, the drawings in the following description are only some embodiments of the present invention, and those skilled in the art can also obtain other drawings based on these drawings without creative labor.

[0038] Figure 1 It shows a schematic diagram of the RFID-based berth positioning method;

[0039] Figure 2 It shows a schematic diagram of the RFID-based berth positioning system;

[0040] Figure 3 It shows a schematic diagram of the electronic tag layout;

[0041] Figure 4 It shows a schematic diagram of the reader transmitting wireless radio frequency signals;

[0042] Figure 5 It shows a schematic diagram of the effect of the RFID system anti-collision scheme based on tag grouping. Detailed implementation mode

[0043] Example 1:

[0044] A berth positioning system and method based on RFID are provided. The berth positioning method is as shown in Figure 1 shown, and the berth positioning system is as shown in Figure 2 shown. Among them, the system includes: an electronic tag for storing the berth electronic tag number, which is installed on the berth; a reader for activating the electronic tag by transmitting a radio frequency signal and reading the electronic tag number; a communication module for transmitting the electronic tag number and the number reception time to the server; a server for storing and processing the received electronic tag number and the number reception time, and performing berth positioning according to the berth tag correspondence table; wherein the reader and the communication module are built on the vehicle.

[0045] The berth positioning system based on RFID provided by the present invention specifically includes:

[0046] The layout of the electronic tags is as shown in Figure 3 shown. The electronic tags are installed on one side of the berth close to the vehicle driving road. Each berth is equipped with at least 1 electronic tag, which is located at 1 / 3 of the corresponding side of the berth. After installation, the electronic tag number and the berth number are recorded and sorted into a berth tag correspondence table, as shown in Table 1. After the reader recognizes the tag later, the corresponding berth number can be queried through this table.

[0047] Table 1. Corresponding relationship table between electronic tags and berths (partial)

[0048]

[0049] The electronic tags are installed on one side of the berth close to the vehicle driving road. Each berth is equipped with 2 electronic tags, which are located at 1 / 3 and 2 / 3 of the corresponding side of the berth respectively.

[0050] The reader activates the electronic tag by transmitting a radio frequency signal and reads the electronic tag number specifically includes: the reader continuously transmits a radio frequency signal with a specific frequency to the outside world through the built-in antenna. The effective scanning range of the radio frequency signal is 1 / 3 of the berth length. When the vehicle travels near the berth, the electronic tag will be activated after entering the range of the radio frequency signal transmitted by the reader, and after being activated, it will transmit the stored electronic tag number data to the reader through the antenna.

[0051] The reader further transmits the received electronic tag number and the timestamp when the reader receives the number data to the server through the communication module; the server stores the received data in a memory array and performs deduplication processing on the data. The deduplication processing specifically means that when the server receives duplicate data, it only retains the data information received for the first time; the array elements of the memory array follow the principle of first in, first out.

[0052] The server performs berth positioning according to the berth relationship correspondence table. Specifically: if the latest number data in the memory array corresponds to the first electronic tag number data of the nth berth, it is determined that the current vehicle is located in the first half of the nth berth; if the latest number data in the memory array corresponds to the second electronic tag number data of the nth berth, it is determined that the current vehicle is located in the second half of the nth berth; the judgment standard for the front and rear positions of the berth follows the front and rear position order in which the vehicle passes through the berths from the berth with a smaller number to the berth with a larger number.

[0053] After the vehicle has passed the last berth in the current berth sequence, no new electronic tag number data will be read into the server's memory array before the vehicle enters a new berth sequence. The server avoids the situation where the last set of number data is reused and the position of the subsequent vehicle movement is continuously determined as the second half of the last berth by clearing the number data in the memory array. Specifically: the server regularly queries whether the reception time of the latest array element in the memory array is earlier than the current system time by 600 ms. If the condition is met, it indicates that the number data in the memory array has expired. At this time, the server clears the memory array to avoid data misuse.

[0054] The reader emits a radio frequency signal such as Figure 4As shown, the vehicle equipped with an RFID reader travels along the outside of the berth, moving from right to left and passing by berths 1, 2, 3, and 4 in sequence. When at berth 1, the reader has passed berth P101 but has not reached berth P102. At this time, the two tag data stored in the memory array are DF11 and DF01 of berth P101. According to the berth relationship table, the corresponding berth number is P101. Therefore, it is determined that the vehicle is at berth P101 and has not reached berth P102, and the system outputs the berth positioning result as berth P101. When the vehicle moves from position 1 to position 2, the reader newly reads the first tag data DF02 of berth P102. At this time, the tag data stored in the memory array are DF02, DF11, and DF01 in sequence. According to the berth relationship table, the berth number corresponding to DF02 is P102, while the berth numbers corresponding to DF11 and DF01 are P101. At this time, it is determined that berth P101 is the previous berth passed by the vehicle, and the current vehicle is in the first half of berth P102. The system outputs the berth positioning result as berth P102. When the vehicle moves from position 2 to position 3, the reader newly reads the second tag data DF12 of berth P102. At this time, the tag data stored in the memory array are DF12, DF02, and DF11 in sequence. According to the berth relationship table, the berth numbers corresponding to DF12 and DF02 are P102, while the berth number corresponding to DF11 is P101. At this time, it is determined that berth P101 is the previous berth passed by the vehicle, and the current vehicle is in the second half of berth P102. The system outputs the berth positioning result as berth P102. When the vehicle moves further to the left from position 4, the reader newly reads the first tag data DF03 of berth P103. At this time, the tag data stored in the memory array are DF03, DF12, and DF02 in sequence. According to the berth relationship table, the berth number corresponding to DF03 is P103, while the berth numbers corresponding to DF12 and DF02 are P102. At this time, it is determined that P102 is the previous berth passed by the vehicle, and the current vehicle is in the first half of berth P103. The system outputs the berth positioning result as berth P103. The berth determination method for subsequent positions is a cycle of the above several situations.

[0055] The system adopts an RFID system anti-collision scheme based on tag grouping to avoid signal collision problems caused by multiple RFID electronic tags entering the reader radio frequency field range simultaneously due to the berth layout, such as Figure 5As shown, it can be seen that after adopting the anti-collision scheme of the present invention, the collision rate can be significantly controlled. It solves the signal collision problem by grouping the electronic tags and identifying the tags in the tag group batch by batch according to the binary tree search algorithm. Specifically, it includes: grouping the RFID tags in the berth area, and keeping the number of tags in each group within a certain range to reduce the possibility of signal collision; allocating specific communication time slots for each tag group, and applying the ALOHA-based algorithm within each tag group to randomly allocate time slots and reduce the collision between tags; when the reader detects a signal collision, rescheduling or selecting the colliding tags according to the rules of the anti-collision algorithm until the collision is resolved; after successfully identifying each tag, calculating the relative position of the tag by receiving the signal strength indication value, so as to realize berth positioning.

[0056] Embodiment 2:

[0057] On the basis of the foregoing embodiment, a deep belief network scheme is added to reduce the influence of multipath effect and radio frequency signal attenuation on the berth positioning of the RFID system. It extracts effective feature information from the RFID data so that the system can better adapt to complex indoor and outdoor environments;

[0058] Among them, it is necessary to collect the RSSI values of the electronic tags and normalize the collected RSSI data to eliminate the signal strength differences in different environments to ensure the consistency of the data; and build a fingerprint database by recording the coordinates of its known positions to provide a basis for subsequent algorithm training and positioning.

[0059] Design a deep belief network structure, including an input layer, multiple hidden layers and an output layer; initialize the network parameters, including the weight matrix and the bias vector. Among them, the weight update formula:

[0060]

[0061] Among them, represents the updated weight from the hidden layer to the output layer; represents the current weight from the hidden layer to the output layer; represents the learning rate, which controls the step size of weight update; represents the partial derivative of the loss function with respect to the weight, indicating how to adjust the weight to reduce the error.

[0062] Use the restricted Boltzmann machine for layer-by-layer pre-training and extract features; each restricted Boltzmann machine layer can be regarded as a feature extractor and is trained by the following formula:

[0063]

[0064] Among them, Represents the state of a given hidden layer Under which The probability that the visible unit Represents the Sigmoid function, which is used to convert the input into a probability; Represents the weights connecting the visible units and the hidden units; Represents the state of the hidden layer units; Represents the bias term, which affects the baseline value of the probability.

[0065] Based on pre-training, the network is fine-tuned using labeled data to optimize the network parameters. The mean squared error is used as the loss function during the fine-tuning process:

[0066]

[0067] Where Represents the mean squared error, which measures the difference between the model prediction and the actual value; Represents the expected output, that is, the target value in the training data; Represents the actual output of the network, that is, the result predicted by the model.

[0068] During localization, the RSSI data of the tag to be located is collected, features are extracted through the network, and matched with the feature database obtained in the training stage to estimate the position of the tag to be located.

[0069] The particle swarm optimization algorithm is used to further optimize the parameters of the restricted Boltzmann machine to improve the accuracy and efficiency of the positioning system. In the particle swarm optimization algorithm, the particle position and velocity update formulas are as follows:

[0070]

[0071]

[0072] Where Represents the velocity of the th particle at time ; Represents the velocity of the th particle at time ; Represents the cognitive coefficient, which affects the tendency of the particle to move towards its historical best position; And Represents a random number between 0 and 1, which is used to increase the randomness of the algorithm; Represents the historical best position of particle ; Represents the social coefficient, which affects the tendency of the particle to move towards the global best position of the population; Represents the global best position of the population; Represents particle at time position; representing the particle at time new position.

[0073] For example, the average RSSI values of a tag measured by 4 RFID readers in a parking lot are: , , and ; these values are normalized to train a deep belief network;

[0074] Assume there is only one restricted Boltzmann machine with 4 visible units and 10 hidden units. During training, the weights and biases are updated. The initial weights and biases are randomly set. For example, the weights are distributed in the interval [0, 0.1]; the visible unit bias ; the hidden unit bias is distributed in the interval [0, 0.1];

[0075] Using the contrastive divergence method, the weight update after one iteration: Assume the learning rate is ; the data expectation is 0.5; the reconstruction expectation is 0.3, then the weight update is:

[0076]

[0077] If the initial weight is 0.05, then the updated weight is:

[0078]

[0079] Suppose there are 5 particles, and the position of each particle represents the weights in the deep belief network. The velocity update and position update are as follows:

[0080] The initial particle positions and velocities are randomly set;

[0081] Inertia weight ; cognitive coefficient ; social coefficient ; random number ; random number ; update the velocity and position:

[0082]

[0083]

[0084] The effect of the deep belief network solution is shown in Table 2 as follows:

[0085] Table 2. Summary of the effect of the deep belief network solution

[0086]

[0087] As shown in Table 2, the model optimized by the deep belief network solution provides predicted coordinates closer to the actual position, reducing the positioning error. This indicates that the deep belief network solution can significantly improve the accuracy of the RFID-based berth positioning method.

[0088] Those skilled in the art should understand that the embodiments of the present invention may be provided as a method, a system, or a computer program product. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable non-transitory storage media containing computer-usable program code.

[0089] The present invention can provide computer program instructions to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, such that the instructions executed by the processor of the computer or other programmable data processing devices generate a device for implementing the system.

[0090] These computer program instructions can also be stored in a computer-readable memory capable of guiding the computer or other programmable data processing devices to work in a specific manner, such that the instructions stored in the computer-readable memory generate a manufactured article including an instruction device, and the instruction device implements the functions of the system.

[0091] These computer program instructions can also be loaded onto the computer or other programmable data processing devices, such that a series of operation steps are executed on the computer or other programmable devices to generate computer-implemented processing, and thus the instructions executed on the computer or other programmable devices provide steps for implementing the functions of the system.

Claims

1. An RFID-based berth positioning system, characterized in that: Including: An electronic tag, which is used to store the berth electronic tag number and is installed on the berth; a reader, which activates the electronic tag by transmitting a radio frequency signal and reads the electronic tag number; a communication module, which is used to transmit the electronic tag number and the number receiving time to the server; A server for storing and processing received electronic tag numbers and number reception times, and performing berth positioning according to a berth tag correspondence table, including: establishing a first-in, first-out memory array to store data, and only retaining the first received record for duplicate numbers; matching the berth position according to the latest number in the array: if the latest number data in the array corresponds to the first electronic tag number data of the nth berth, it is determined that the current vehicle is located in the front half of the nth berth; if it corresponds to the second electronic tag number data of the nth berth, it is determined that it is located in the rear half of the nth berth; the judgment standard for the front and rear positions of the berth follows the front and rear position order in which the vehicle passes through the berths from the berth with a smaller number to the berth with a larger number; when the vehicle has passed the last berth in the current berth sequence, the server regularly queries whether the reception time of the latest array element in the memory array is earlier than the current system time by 600 ms. If the condition is met, it indicates that the number data in the memory array has expired. At this time, the server clears the memory array to avoid data misuse; An anti-collision module based on tag grouping is used to avoid signal collision problems caused by multiple RFID electronic tags simultaneously entering the reader radio frequency field range due to berth layout. It solves the signal collision problem by grouping the electronic tags and identifying the tags in the tag group in batches according to the binary tree search algorithm; A deep belief network module is used to reduce the influence of multipath effects and radio frequency signal attenuation on the berth positioning of the RFID system. It enables the system to better adapt to complex indoor and outdoor environments by extracting effective feature information from RFID data. Among them, the parameters of the restricted Boltzmann machine are optimized by the particle swarm optimization algorithm, and the position and velocity update formulas of the particles are as follows: ; ; In the formula, represents the velocity of the th particle at time ; represents the velocity of the th particle at time ; represents the cognitive coefficient; and represent random numbers between 0 and 1; represents the historical best position of particle ; represents the social coefficient; represents the global best position of the population; represents the position of particle at time ; represents the new position of particle at time ; Among them, the reader and the communication module are built on the vehicle.

2. The RFID-based berth positioning system according to claim 1, wherein: The electronic tag is installed on one side of the berth close to the vehicle driving road. At least one electronic tag is equipped for each berth, and it is located at the 1 / 3 position of the corresponding side of the berth.

3. The RFID-based berth positioning system according to claim 1, wherein: The reader activates the electronic tag by transmitting a radio frequency signal and reads the electronic tag number specifically as follows: The reader continuously transmits a radio frequency signal with a specific frequency to the outside through the built-in antenna. The effective scanning range of the radio frequency signal is 1 / 3 of the berth length. When the vehicle travels near the berth, the electronic tag will be activated after entering the range of the radio frequency signal transmitted by the reader, and after being activated, it will transmit the stored electronic tag number data to the reader through the antenna.

4. The RFID-based berth positioning system according to claim 3, wherein: The reader further transmits the received electronic tag number and the timestamp when the reader receives the number data to the server through the communication module; the server stores the received data in the memory array and performs deduplication processing on the data. The deduplication processing specifically means that when the server receives duplicate data, it only retains the data information received for the first time; the array elements of the memory array follow the principle of first in first out.

5. The RFID-based berth positioning system according to claim 1, wherein: The method for the anti-collision module based on tag grouping to solve the signal conflict problem includes: grouping the RFID tags in the berth area, keeping the number of tags in each group within a certain range to reduce the possibility of signal conflict; allocating specific communication time slots for each tag group, and randomly allocating time slots within each tag group; when the reader detects a signal conflict, re-scheduling or selecting the conflicting tags according to the anti-collision rules until the conflict is resolved; after successfully identifying each tag, calculating the relative position of the tag by receiving the signal strength indication value.

6. An RFID-based berth positioning method, characterized in that: The implementation of the method is based on the system according to any one of claims 1-5: The method includes: Installing an electronic tag for storing the berth number on the berth; Formulating a correspondence table between the electronic tag and the berth according to the electronic tag layout; Activating the electronic tag through the reader carried on the vehicle; The reader receives the number data transmitted by the electronic tag and further transmits it to the server together with the number receiving time; The server stores and processes the received electronic tag number and the number receiving time, and performs berth positioning according to the berth tag correspondence table.

7. A computer-readable storage medium storing a computer program therein, characterized in that: When the computer program runs, it implements the RFID-based berth positioning method according to claim 6.

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