Second-hand car warehouse-in and warehouse-out management system and method

Abstract

The invention relates to the technical field of warehouse-in and warehouse-out management, in particular to a second-hand car warehouse-in and warehouse-out management system and method. The system comprises a vehicle RFID tag module, an intelligent electronic price tag module, a warehouse-in management module, a warehouse-out management module, an inventory monitoring and alarming module, a multi-point RFID positioning network module and an inventory map visualization module, and a unique encrypted RFID tag can be configured for each second-hand vehicle; binding an intelligent electronic price tag for each second-hand vehicle, and receiving verification to generate a verification result; collecting label information when the vehicle enters the parking lot; the label information is verified when the vehicle leaves; receiving the verification result of the intelligent electronic price tag and the vehicle in-library data of the database to lock the position of the abnormal vehicle; dense RFID reader nodes are arranged in the market to collect and output positioning data; and receiving the positioning data and the vehicle state information, generating a real-time inventory distribution map, and providing a scheduling and site planning decision basis for a manager. The scheduling and planning efficiency of managers can be improved.

Description

Technical Field

[0001] This invention relates to the field of warehouse management technology, and in particular to a used car warehouse management system and method. Background Technology

[0002] With the large-scale development of the used car market, vehicle entry and exit management and precise inventory control have become core aspects affecting market operational efficiency, transaction experience, and capital turnover. Used car markets are generally characterized by a large number of vehicles, frequent turnover, and rapid information changes (such as price adjustments and status updates). Traditional entry and exit management models, relying on manual registration, verification, and paper records, are no longer suitable for the industry's development needs. This model is not only inefficient but also prone to human error leading to omissions in vehicle information entry and inventory statistics discrepancies. The manual verification process when vehicles leave the market can also cause congestion. Furthermore, updating paper price tags is costly and time-consuming, making it difficult to keep pace with frequently changing vehicle prices, which can easily lead to information asymmetry between buyers and sellers.

[0003] Furthermore, Chinese patent CN109035077A discloses a residential community vehicle access management system, relating to the field of property management system technology. This invention includes a property management system and a vehicle access control system. The property management system is used for overall control of vehicle entry and exit within the community, while the vehicle access control systems are installed at several entrances and exits of the community. Each vehicle access control system individually controls the entry and exit of vehicles at its corresponding entrance and exit. Each vehicle access control system includes a first processor, a access card scanner, a first networked data information unit, and a QR code payment module. This invention, by incorporating a property management system and a vehicle access control system—with the property management system providing overall control of vehicle entry and exit within the community and the vehicle access control systems installed at several entrances and exits, each individually controlling the entry and exit of vehicles at its corresponding entrance and exit—solves the problem of existing community visitors and parking users only being able to enter and exit through a single entrance or exit. This invention solves the problem of vehicles in residential communities only being able to enter and exit through a single entrance and exit, improving the flexibility of vehicle management in the community. However, the solution focuses on basic access control for vehicles belonging to residents and visitors, and is not designed for the core needs of the used car market. It lacks real-time linkage display of vehicle information and prices, and has no inventory monitoring, slow-moving warning, or precise positioning capabilities. It cannot achieve fully automated management of the entire process of used car entry and exit, price updates, and inventory statistics, and is difficult to adapt to the complex operating scenarios of the used car market. Summary of the Invention

[0004] To address the aforementioned technical problems in existing used car entry and exit management processes, this invention provides a used car entry and exit management system that enables encrypted storage and real-time display of vehicle information, identity and location consistency verification to avoid information discrepancies, standardized vehicle entry and exit procedures, automatic updates of status and price, simplified operations while ensuring data accuracy, real-time monitoring of inventory and unsold inventory, timely alarms to identify anomalies, and reduced management risks. It generates an inventory distribution map through triangulation, supports route planning and rapid querying, and comprehensively achieves intelligent vehicle management, visualized inventory, and standardized processes. This improves the efficiency of manager scheduling and planning, optimizes the buyer's car-finding experience, and significantly reduces market operating costs and information asymmetry issues. The system includes the following modules: The vehicle RFID tag module is used to equip each used car with a unique encrypted RFID tag, which stores the vehicle identification number, initial entry time, preset price, and vehicle status information, and supports information exchange and status updates with the reading device. The intelligent electronic price tag module is used to bind an intelligent electronic price tag to each used car, receive and display basic vehicle information, real-time price and status, and has a built-in RFID reading unit that periodically scans surrounding tags to verify the consistency of identity and location and generate verification results. The warehouse management module is used to collect tag information through the RFID reader at the entrance when vehicles enter the warehouse, complete vehicle information registration, vehicle condition verification, and price suggestion generation, and synchronize the warehouse data and price suggestions to the smart electronic price tag module. The outbound management module is used to verify the tag information through the access control RFID reader when a vehicle leaves the site, and update the vehicle status to be sold or left. If a temporary relocation is required, the relocation time, target area and operator are recorded and synchronized to the smart electronic price tag module. The inventory monitoring and alarm module is used to receive the verification results of smart electronic price tags and vehicle inventory data from the database, to calculate the inventory quantity in real time, calculate the duration of slow sales, trigger alarms for inventory exceeding limits or slow sales exceeding time, and to locate abnormal vehicles by combining location information. The multi-point RFID positioning network module is used to deploy dense RFID reader nodes in the market, collect the tag signal strength received by each node, calculate the precise coordinates of the vehicle through the triangulation algorithm, and output positioning data. The inventory map visualization module receives location data and vehicle status information, generates a real-time inventory distribution map, supports buyer queries and optimal vehicle viewing route planning, and provides managers with a basis for scheduling and site planning decisions.

[0005] This invention first equips vehicles with encrypted RFID tags to achieve secure storage and real-time interaction of core information, laying a unique identification foundation for end-to-end management. It then binds smart electronic price tags, which not only intuitively display vehicle information and prices but also ensure identity and location consistency through RFID verification, avoiding information discrepancies and vehicle misplacement. The invention standardizes the vehicle entry and exit process, automatically completing information registration, vehicle condition verification, and price suggestions upon entry, and updating status in real time upon departure. Temporary relocation is fully traceable, solving the problems of low efficiency, error-proneness, and information lag associated with traditional manual registration. Real-time monitoring of inventory and slow-moving goods triggers automatic alarms and locks abnormal vehicles when limits or timeouts are exceeded, reducing inventory backlog and management risks. Through dense RFID nodes and triangulation algorithms, precise vehicle coordinate calculation is achieved, overcoming the limitations of traditional vehicle location difficulties and ambiguous positioning. A real-time inventory distribution map is generated, supporting buyers' quick searches and optimal viewing route planning, improving the car buying experience, and providing managers with data support for scheduling and site planning, optimizing space utilization. The overall solution enables intelligent, visual, and standardized vehicle management throughout the entire process from warehousing, monitoring, and location tracking to vehicle delivery. This significantly reduces manual intervention, lowers operating costs, and ensures transparent and accurate information, alleviating information asymmetry between buyers and sellers, thereby promoting the efficient and orderly development of the used car market.

[0006] Preferably, the vehicle RFID tag module includes the following functions: Each used car is assigned a unique identification tag, and basic information such as vehicle identification number, year of manufacture, model configuration, and initial vehicle condition level is entered into the tag; The entered basic information is encrypted using a symmetric encryption algorithm, and the encrypted core data block is stored in the secure storage area of ​​the RFID tag. When a vehicle enters the site, it establishes a communication connection with the RFID reader at the entrance, receives the entry timestamp sent by the reader, and updates the entry status in the tag to pending confirmation. When a vehicle leaves or is moved, it interacts with the access control or area reader to receive a status update instruction and changes the vehicle status in the tag to sold, departed, or being moved. It regularly responds to scanning requests from the built-in reading unit of the smart electronic price tag, outputs encrypted identity information for verification, and ensures that the binding relationship between the tag and the vehicle is not tampered with.

[0007] This invention completely solves the core pain points of the used car market—chaotic vehicle identification, easy information tampering, and delayed status updates—through end-to-end information management and secure interaction using encrypted RFID tags. Each used car is assigned a unique identification tag, and basic information such as the vehicle identification number and model configuration is entered, establishing a unique "digital ID card" for the entire vehicle lifecycle management. This avoids the problems of vehicle information confusion and difficulty in traceability in traditional management. A symmetric encryption algorithm processes core information and stores it in a secure storage area, effectively preventing illegal tampering or theft of information and ensuring the security and reliability of vehicle information. When a vehicle enters, leaves, or is moved, it interacts with the reader in real time to update its status, achieving dynamic synchronization of vehicle status and solving the drawbacks of traditional manual status recording, which is prone to errors and information lag. It periodically responds to scanning requests from smart electronic price tags and outputs encrypted identity information, ensuring that the tag-vehicle binding relationship is not tampered with, technically eliminating the risk of vehicle misplacement and information fraud. The tag management system built in this step, which combines "unique identifier + encrypted storage + real-time interaction + status traceability," provides a safe and reliable foundation for the intelligent management of the entire used car market process, and significantly improves the accuracy and security of vehicle management.

[0008] Preferably, the smart electronic price tag module includes the following functions: Receive vehicle basic information, price suggestions and inventory status synchronized from the inventory management module, convert the data into a standardized display format, and display the vehicle identification number, price, vehicle condition level and inventory status in the price tag screen in sections; The built-in RFID reading unit is activated according to the preset scanning cycle, and a fixed frequency radio frequency detection signal is emitted to the surrounding area; The system receives encrypted response signals from RFID tags on vehicles within its range, amplifies and filters the signals, and extracts encrypted identity information. The decryption algorithm is called to decrypt the encrypted identity information to obtain the target vehicle identification number. The target vehicle identification number is then compared field by field with the vehicle identification number bound to the target vehicle to generate an identity and location consistency verification result. It establishes a long-term connection with the market management database in real time, receives update instructions such as price adjustments and status changes issued by the database, refreshes the price tag display content synchronously, and uploads the verification results and update status to the inventory monitoring and alarm module.

[0009] This invention addresses the problems of inconsistent information display, difficulty in verifying identity and location, and untimely data updates in traditional used car markets through intelligent electronic price tags. The tags feature information display, automatic verification, and real-time synchronization. Standardized display of core information such as vehicle identification number (VIN), price, and vehicle condition rating allows buyers to intuitively access key information, overcoming the drawbacks of incomplete information, easy wear and tear, and cumbersome modification associated with traditional paper price tags. The built-in RFID reader scans surrounding tags at preset intervals, automatically verifying identity and location consistency without manual intervention, improving verification efficiency and preventing vehicle misplacement due to human error. After decryption and comparison, the verification result is generated and uploaded to the inventory monitoring module in real time, allowing managers to promptly identify vehicle status anomalies and reduce management risks. A long-term connection is established with the market management database to synchronously receive price adjustment and status change commands and refresh the display, ensuring real-time consistency between price tag information and system data. This solves the problems of discrepancies between traditional price tags and actual selling prices, and delayed status updates. This step realizes a price tag management model of "information visualization + automated verification + data synchronization", which not only optimizes the buyer's car purchase experience, but also provides data support for the refined management of the market, and promotes the transparency of used car transaction information and the efficiency of management.

[0010] Preferably, the step of activating the built-in RFID reading unit to scan surrounding tags according to a preset cycle includes: The system reads the preset scanning cycle parameters from the smart electronic price tag, which are dynamically adjusted by the system based on the market vehicle density. When the scanning time point is reached, the transmitting circuit of the built-in RFID reading unit is activated, generating a radio frequency detection signal that conforms to the ISO standard and transmitting it to a preset radius range centered on the price tag; The system receives response signals from RFID tags of vehicles within its range, performs noise reduction and shaping on the signals, and removes noise caused by environmental interference and signal attenuation. The processed valid signal is converted into a digital signal stream, and the encrypted identity information field and signal strength value are parsed out according to the communication protocol of the RFID tag; The encrypted identity information is parsed and its integrity is verified. The data length and check bits are checked to see if they meet the preset specifications, and valid identity information is filtered out. The system compares the valid identity information with the vehicle identification number bound to it. If they match, a verification result is generated. If they do not match or no matching tag is detected, an error message is generated and synchronized to the inventory monitoring and alarm module.

[0011] This invention comprehensively addresses the core pain points of traditional RFID scanning—low efficiency, weak anti-interference capability, and unreliable verification results—by dynamically adjusting the scanning cycle, precisely processing signals, and employing a rigorous verification mechanism. The scanning cycle is dynamically adjusted based on market vehicle density; it can be shortened to increase verification frequency when vehicles are dense, and extended to save energy when vehicles are sparse, achieving a balance between efficiency and energy consumption and avoiding resource waste or untimely verification issues caused by fixed-cycle scanning. It emits RF detection signals conforming to ISO standards and limits the preset radius range to ensure targeted scanning and reduce interference from irrelevant signals. The received signal undergoes noise reduction and shaping processing to effectively filter environmental interference and noise caused by signal attenuation, improving the accuracy of signal identification. After signal parsing, integrity verification is performed, checking whether the data length and check bits are compliant, filtering out valid identity information, and avoiding verification errors caused by invalid data. Verification results are generated by comparing the data with the vehicle identification number bound to the vehicle, and abnormal situations are reported promptly to ensure consistency between vehicle identity and location. The refined and highly reliable scanning and verification process constructed in this step not only ensures the accuracy and timeliness of identity and location verification, but also has good environmental adaptability and resource optimization capabilities, providing stable and efficient technical support for the dynamic monitoring of vehicles in the used car market.

[0012] Preferably, the integrity verification of the parsed encrypted identity information includes: Extract the data length field from the parsed encrypted identity information and compare it with the system's preset standard data length; If the data lengths are consistent, extract the cyclic redundancy check code at the end of the information and perform cyclic redundancy check calculation on the entire encrypted data block. The calculated check code is compared with the extracted check code to determine whether there is any loss or tampering during data transmission. If the verification code matches, further verify the format identifier bit of the encrypted data block to confirm that the data conforms to the tag's storage format specification; Generate integrity verification results. If all verification items pass, the data is marked as valid identity information; otherwise, it is marked as invalid data and discarded. Valid identity information is transmitted to the next comparison process, while the reception time and signal strength information of invalid data are recorded for subsequent positioning network optimization.

[0013] This invention completely solves the problems of verification failure caused by data loss, tampering, and abnormal format in traditional RFID data transmission through a multi-level integrity verification mechanism and data traceability design. First, it compares the data length with a preset standard to quickly filter incomplete data caused by transmission interruptions or signal interference. Then, it uses cyclic redundancy check code comparison to accurately detect data loss or tampering during transmission, ensuring data integrity. Finally, it verifies the format identifier bit to ensure the data conforms to tag storage specifications, preventing abnormal format data from affecting subsequent comparisons. This multi-level verification system progressively checks data length, integrity, and format compliance, significantly improving the reliability of identity information and avoiding misjudgments or system anomalies caused by invalid data. Simultaneously, it records the reception time and signal strength of invalid data, providing data support for subsequent positioning network optimization, assisting in adjusting reader deployment or signal parameters, further improving the overall system stability, and upgrading identity verification from a "single comparison" to a closed-loop mechanism of "precise verification + optimization feedback."

[0014] Preferably, the warehouse management module includes the following functions: When a vehicle enters the market entrance, it triggers the RFID reader at the entrance to read the encrypted basic information in the vehicle's RFID tag. The encrypted basic information is decrypted, the vehicle identification number is extracted, and compared with the vehicle information already registered in the market database to determine whether it is the first time it has entered the database. If it is the first time the vehicle is put into the warehouse, the vehicle condition verification process will be initiated. High-definition cameras will be used to collect images of the vehicle's exterior, sensors will be used to detect the status of key components, and a vehicle condition level assessment result will be generated. Call the price generation model, input the vehicle brand, model, vehicle condition level, years of use, and market supply and demand parameters, and generate an initial price suggestion; Enter the vehicle identification number, entry time, vehicle condition level, and suggested price information into the market database to create a vehicle entry file; The core display information in the inbound file is synchronized to the corresponding smart electronic price tag module, triggering a price tag display update, and the vehicle status is set to in stock.

[0015] This invention addresses the core pain points of traditional used car registration—low efficiency, cumbersome data entry, and subjective assessment of vehicle condition and price—by automating the warehousing process and synchronizing data. Upon vehicle entry, an RFID reader automatically collects and decrypts information, comparing it with a database to determine if it's the first time the vehicle is being registered, avoiding duplicate registrations and significantly simplifying manual data entry. For the first entry, high-definition cameras and sensors automatically collect vehicle condition data, generating an objective condition rating, overcoming the limitations of relying on manual experience and improving the fairness and accuracy of the assessment. A price generation model is invoked, combining multi-dimensional parameters to generate initial price suggestions, providing data-driven pricing and avoiding price deviations caused by subjective pricing. A vehicle entry file is created and core information is synchronized to a smart electronic price tag, achieving real-time linkage between entry data and price tag display, solving the problem of delayed price tag updates after traditional entry. The "automatic identification + intelligent verification + data linkage" warehousing system built in this step significantly shortens the warehousing process time, reduces human error, ensures the accuracy and consistency of warehousing information, and lays a standardized data foundation for subsequent inventory management and sales display.

[0016] Preferably, the inventory monitoring and alarm module includes the following functions: The system reads the entry time, current status, and price information of all vehicles in the market database in real time to create a dynamic inventory list. Receive the identity and location consistency verification results uploaded by the smart electronic price tag module, and mark the vehicles marked as abnormal separately; The total number of vehicles in the dynamic inventory list that are in stock is counted and compared with the system's preset inventory upper limit threshold. Calculate the unsold duration of each vehicle in the warehouse, which is the difference between the current time and the time of entry into the warehouse, and compare it with the preset unsold duration threshold. If the total inventory exceeds the upper limit threshold, an inventory over-limit alarm message will be generated, including the current inventory quantity, the over-limit difference, and the suggested scheduling direction; If there are vehicles whose unsold period exceeds the threshold, an unsold period alarm message will be generated, which includes the vehicle identification number, unsold period, and current price. It receives positioning data from a multi-point RFID positioning network module, associates the location information of abnormal vehicles, over-limit inventory vehicles, and slow-selling vehicles with alarm information, and generates a comprehensive alarm notification to send to the management terminal.

[0017] This invention comprehensively addresses the management pain points of traditional used car markets, such as lagging inventory statistics, difficulty in identifying slow-moving vehicles, and difficulty in locating abnormal vehicles, through real-time inventory monitoring, multi-dimensional alarms, and location correlation. It establishes a dynamic inventory list by reading vehicle information from the database in real time, accurately counting the total number of vehicles in stock, and generating inventory over-limit alarms by comparing them with preset thresholds. This helps managers to optimize site utilization in a timely manner and avoid inventory backlog. It also calculates the duration of slow-moving inventory for each vehicle and triggers overtime alarms, quickly exposing slow-moving vehicles and allowing managers to adjust prices or promotional strategies promptly, reducing the risk of capital tied up. Furthermore, it receives anomaly verification results from smart electronic price tags, individually marks abnormal vehicles, and uses location data to pinpoint their location, solving the problems of difficulty in finding and passive management of abnormal vehicles in traditional systems. The generated comprehensive alarm notification integrates vehicle location, anomaly type, and over-limit / slow-moving data, providing managers with clear decision-making basis and upgrading inventory management from "passive statistics" to "proactive monitoring + precise early warning." This module achieves real-time linkage of inventory, vehicle condition, and location information, significantly improving the precision and efficiency of market management and reducing management costs and operational risks.

[0018] Preferably, the multi-point RFID positioning network module includes the following functions: High-density RFID reader nodes are deployed at key locations such as intersections, parking areas, and entrances / exits within the market. Each node has a built-in location coordinate chip. Each reader node is continuously in signal receiving mode, collecting radio frequency signals emitted by RFID tags of surrounding vehicles in real time, and recording the signal reception time and signal strength value; Each node packages the collected signal strength value, its own location coordinates, and the signal reception timestamp into a positioning data frame, and uploads it to the positioning computing unit through the wireless communication network. The positioning calculation unit receives positioning data frames from multiple nodes for the same vehicle within the same time period and filters out valid data frames with signal strength greater than a threshold. The signal strength values ​​in the valid data frames are normalized to eliminate errors caused by hardware differences between different nodes; The triangulation algorithm is used to construct a positioning triangle with the coordinates of each node as the vertices and the distance corresponding to the normalized signal strength as the side length. The centroid coordinates of the positioning triangle are calculated and corrected using a signal strength weighting factor to obtain the precise position coordinates of the vehicle. The precise location coordinates are checked for boundaries to ensure that they fall within the pre-defined geographical area of ​​the market, generating valid location data and feeding it back to the inventory monitoring and alarm module and the inventory map visualization module.

[0019] This invention completely solves the core pain points of ambiguous vehicle positioning and inaccurate location tracking in the traditional used car market by deploying high-density nodes, processing multi-dimensional data, and using precise positioning algorithms. High-density RFID reader nodes with built-in location coordinate chips are deployed in key market locations to construct a fully covered, blind-spot-free positioning network, ensuring that vehicles can be effectively detected in any area and avoiding the signal blind spots caused by sparse positioning nodes in traditional methods. Each node collects signal strength and reception time in real time, packages and uploads positioning data frames, providing rich raw data support for accurate calculations. The positioning calculation unit filters valid data frames and performs normalization processing, eliminating errors caused by hardware differences and ensuring data consistency. The triangulation algorithm, combined with signal strength weighting factor correction and boundary verification, significantly improves the accuracy of location coordinates, overcoming the shortcomings of traditional positioning algorithms that are susceptible to environmental interference and have large errors. The effective positioning data generated in this step enables real-time and accurate vehicle location tracking, providing core data support for inventory monitoring, anomaly alarms, and route planning. This breaks the limitations of the traditional used car market's "difficulty in finding and locating vehicles," significantly improving market operation efficiency and management sophistication.

[0020] Preferably, the step of calculating the precise vehicle position coordinates using a triangulation algorithm includes: Extract the position coordinates of at least three different nodes and their corresponding normalized signal strength values ​​from the valid data frame; Based on the radio frequency signal propagation attenuation model, the normalized signal strength value of each node is converted into the straight-line distance from the vehicle to that node; Establish a two-dimensional rectangular coordinate system with the position coordinates of the first node as the origin, and convert the position coordinates of other nodes into coordinate values ​​in this coordinate system; Based on the coordinates and corresponding distances of the three nodes, three sets of distance equations are listed to form a system of equations; The system of equations is solved using the least squares method to obtain the initial coordinates of the vehicle in this coordinate system. The initial coordinate values ​​are converted into market-standard geographic coordinates to obtain preliminary positioning coordinates; Extract the vehicle's historical positioning data, calculate the deviation between the preliminary positioning coordinates and the historical coordinates, and perform smoothing if the deviation exceeds a preset threshold. By combining the signal strength weights of each node, the initial positioning coordinates are weighted and corrected to generate the final accurate position coordinates; The precise location coordinates are associated with the node number and the calculation timestamp to form a complete location data record.

[0021] This invention comprehensively addresses the core pain points of traditional triangulation algorithms—insufficient accuracy, coordinate drift, and poor stability—through multi-node data fusion and multi-algorithm collaborative optimization. It extracts the coordinates and normalized signal strength of at least three nodes, converting them into straight-line distances based on a radio frequency signal propagation attenuation model, providing a reliable distance basis for positioning calculations. A two-dimensional rectangular coordinate system is established, and a set of distance equations is listed. The initial coordinates are solved using the least squares method, ensuring the mathematical rigor of the calculation results and avoiding the error accumulation caused by traditional approximation calculations. The initial coordinates are converted into a unified geographic coordinate system, and deviation verification and smoothing are performed using historical positioning data, effectively suppressing coordinate drift and improving positioning stability. Finally, signal strength-weighted correction generates the final accurate coordinates, allowing node data with better signal quality to play a greater role and further improving positioning accuracy. The "distance conversion - equation solving - deviation correction - weighted optimization" full-process positioning calculation system constructed in this step not only ensures the accuracy and stability of positioning, but also has good environmental adaptability. It can effectively cope with complex scenarios such as vehicle movement and signal interference, providing reliable technical support for the accurate positioning of vehicles in the used car market, and upgrading vehicle location tracking from "rough estimation" to "precise locking".

[0022] As a preferred embodiment, the second technical solution of the present invention is a method for managing the entry and exit of used cars, wherein the method is implemented based on the used car entry and exit management system described above, and the used car entry and exit management method includes the following steps: Step S01: Install a unique encrypted RFID tag on each used car, enter the basic vehicle information and store it encrypted, and complete the binding of the tag to the vehicle; Step S02: Bind the smart electronic price tag to the vehicle, establish a communication connection between the price tag, RFID tag, and market database, and complete the initial information synchronization and display; Step S03: When a vehicle enters the parking lot, the RFID reader at the entrance collects the tag information, completes the vehicle condition verification and price suggestion generation, registers the vehicle in the storage file and updates the price tag display; Step S04: The smart electronic price tag periodically scans the tags to generate verification results, the positioning network calculates the precise location of the vehicle, and the monitoring module counts inventory and unsold goods and triggers an alarm. Step S05: When a vehicle leaves the premises, the tag information is verified by the access control reader, and the status is updated to "sold" or "departed"; when a temporary transfer occurs, the transfer information is recorded and synchronized to the price tag and the database; Step S06: Generate an inventory map based on location data and vehicle status, supporting querying and route planning, and providing data support for management decisions.

[0023] This invention precisely addresses the core pain points of traditional used car inventory management—cumbersome processes, asynchronous information, and low efficiency—through a closed-loop design and multi-module collaborative linkage. By installing and binding encrypted RFID tags to vehicles, a unique and secure vehicle identity is established, laying the foundation for end-to-end management. Binding smart electronic price tags and synchronizing information enables visualized display and real-time updates of vehicle information, solving the problems of outdated and cumbersome modification of traditional price tags. Automated entry verification, price suggestions, and inventory registration significantly shorten the inventory process time and avoid human error. Intelligent verification, precise positioning, and real-time monitoring enable dynamic tracking and anomaly warnings of vehicle status, shifting management from "passive response" to "proactive prevention." Standardized departure and relocation processes ensure real-time synchronization of status updates, avoiding information chaos. The generation of inventory maps with query and route planning optimizes the buyer experience and provides managers with data-driven decision-making support. This method enables intelligent and standardized management of the entire process of used cars from warehousing, monitoring, and location to delivery, significantly reducing manual intervention, lowering operating costs and management risks, while ensuring information transparency and accuracy, and promoting the efficient and orderly development of the used car market.

[0024] It has the following beneficial effects: (1) By constructing a vehicle's "digital ID card" through a unique encrypted RFID tag, the core pain points of the traditional used car market—chaotic vehicle identification, easy information tampering, and difficulty in tracing status—are completely resolved. Each used car is equipped with a unique RFID tag that stores core information such as vehicle identification number, entry time, price, and status, establishing a unique identification foundation for the entire lifecycle management of the vehicle. This avoids the problems of information confusion and duplicate statistics in traditional manual registration. Encryption technology is used to process core information, effectively preventing illegal tampering or theft of information and ensuring the security and credibility of vehicle information. The tag supports real-time interaction and status updates with the reading device, providing data interaction support for the entire process of subsequent entry registration, exit verification, and transfer records, breaking the limitations of traditional isolated information storage and difficulty in linkage. The "unique identification + encrypted storage + real-time interaction" tag system constructed in this step lays a safe and reliable data foundation for the entire process management of used car entry and exit, inventory monitoring, and location tracking, allowing vehicle management to shift from "manual recording" to "intelligent traceability," significantly improving the accuracy and security of management.

[0025] (2) By linking intelligent electronic price tags with RFID verification, the problems of non-standard information display, difficulty in verifying identity and location, and untimely data updates in the traditional used car market are accurately solved. The intelligent electronic price tag intuitively displays the vehicle's basic information, real-time price, and status, allowing buyers to quickly obtain key information and solving the drawbacks of incomplete information, easy wear and tear, and cumbersome modification of traditional paper price tags. The price tag has a built-in RFID reading unit that regularly scans surrounding tags to automatically verify the consistency of identity and location without manual intervention, which not only improves verification efficiency but also avoids management chaos caused by vehicle misplacement and information fraud. The verification results are fed back to the management system in real time, allowing managers to promptly grasp abnormal vehicle status and reduce management risks. At the same time, the price tag can receive update instructions issued by the system to synchronously refresh the price and status, ensuring that the displayed information is consistent with the database in real time, solving the problems of inconsistent prices and actual selling prices and delayed status updates in traditional price tags. This step realizes a price tag management model of "information visualization + automated verification + data synchronization", which not only optimizes the buyer's car purchase experience but also provides data support for refined market management, promoting transparency and efficiency in used car transaction information.

[0026] (3) By automating the warehousing process and synchronizing data, the core pain points of traditional used car warehousing registration—low efficiency, cumbersome information entry, and subjective assessment of vehicle condition and price—are comprehensively resolved. When a vehicle enters the warehouse, the RFID reader at the entrance automatically collects tag information, eliminating the need for manual entry and significantly reducing warehousing time, thus avoiding errors caused by manual operation. The system automatically completes vehicle information registration and initiates the vehicle condition verification and price suggestion generation process. By replacing manual experience-based judgment with technological means, the objectivity of vehicle condition assessment and the rationality of price suggestions are improved, breaking the limitations of traditional warehousing that relies on manual labor and involves cumbersome processes. Warehousing data and price suggestions are synchronized to the intelligent electronic price tag in real time, achieving seamless integration of "warehousing registration + information display," solving the problem of delayed price tag information updates after traditional warehousing. This step constructs an "automatic identification + intelligent verification + data linkage" warehousing system, making the warehousing process more standardized, efficient, and accurate, laying a standardized data foundation for subsequent inventory management and sales display, and reducing manual management costs.

[0027] (4) By standardizing the departure and relocation management process, the problems of unclear vehicle departure records, untraceable relocation, and delayed status updates in traditional used car markets have been completely solved. When a vehicle leaves the market, the access control RFID reader automatically verifies the tag information to ensure the accurate identity of the departing vehicle and avoid the risk of misplacement or omission of vehicles; the vehicle status is updated in real time to show whether it has been sold or left the market, ensuring that the system data is consistent with the actual vehicle condition, solving the drawbacks of delayed and easily missed departure information in traditional manual registration. For temporary relocation scenarios, the system records the relocation time, target area, and operator in detail, achieving full traceability of the relocation process, which is convenient for subsequent traceability and management, and avoids the problem of vehicle location confusion and difficulty in finding after relocation; all status change information is synchronized to the smart electronic price tag to ensure that the price tag display content is accurate in real time, allowing buyers and managers to keep abreast of the latest vehicle status. The departure management system of "automatic verification + status synchronization + relocation traceability" built by this step makes the vehicle departure and relocation process more standardized and transparent, greatly improving the level of market management and reducing operational risks.

[0028] (5) By implementing real-time inventory monitoring and a multi-dimensional alarm mechanism, the system precisely addresses the management pain points of traditional used car markets, such as lagging inventory statistics, difficulty in identifying slow-moving vehicles, and difficulty in locating abnormal vehicles. The system receives the verification results of smart electronic price tags and the in-stock data in the database in real time, dynamically calculates the inventory quantity, compares it with the preset upper limit threshold, and generates an inventory over-limit alarm. This helps managers to promptly dispatch vehicles, optimize site utilization, and avoid inventory backlog. The system automatically calculates the slow-moving time of each vehicle, compares it with the preset threshold, and triggers a slow-moving timeout alarm, allowing slow-moving vehicles to be quickly exposed. This facilitates timely price adjustments or promotional strategies by managers, reducing the risk of capital occupation. By combining location information to locate abnormal vehicles, the system solves the traditional problems of difficulty in finding abnormal vehicles and passive management, enabling managers to respond quickly and handle issues promptly. This step realizes the transformation of inventory management from "passive statistics" to "active monitoring + precise early warning," ensuring the accuracy and real-time nature of inventory data and providing managers with clear decision-making basis, significantly improving market operation efficiency and risk control capabilities.

[0029] (6) By deploying dense RFID nodes and using triangulation algorithms, the core pain points of unclear vehicle positioning and difficulty in finding vehicles in traditional used car markets have been comprehensively solved. Dense RFID reader nodes are deployed in key locations within the market to construct a fully covered, dead-angle-free positioning network, ensuring that vehicles can be effectively detected in any area and avoiding the signal blind spots caused by the sparse positioning nodes of traditional methods. Each node collects the signal strength of the vehicle's RFID tags in real time, providing rich raw data support for positioning calculations. By using triangulation algorithms and combining signal strength analysis to calculate the precise coordinates of vehicles, the drawbacks of large errors and low accuracy in traditional positioning methods have been solved, achieving precise vehicle location locking. The positioning data generated in this step provides core technical support for the subsequent generation of inventory distribution maps and optimal vehicle viewing route planning, breaking the limitations of traditional used car markets where "finding a car relies entirely on asking and positioning relies on memory," upgrading vehicle positioning from "rough estimation" to "precise tracking," and significantly improving market operation efficiency and buyer's car buying experience.

[0030] (7) By generating a real-time inventory distribution map and adapting to multiple scenarios, the system completely solves the problems of low inventory visualization, difficulty for buyers to find cars, and lack of data support for managers' decision-making in the traditional used car market. The system receives location data and vehicle status information, generates a real-time inventory distribution map, and intuitively presents the location and status of all vehicles, allowing managers to grasp the market inventory situation at a glance. This solves the drawbacks of traditional inventory management, which relies on manual statistics and has low visualization. It also supports buyers in querying target vehicles and planning the optimal viewing route, greatly shortening the time spent finding cars and improving the car buying experience. This solves the problems of cumbersome and inefficient car finding in traditional markets. At the same time, the inventory distribution map provides managers with accurate data support for vehicle scheduling and site planning, helping to optimize vehicle placement and layout, improve site utilization, and shift management decisions from "experience-based judgment" to "data-driven." This step realizes the visualization of inventory management, the convenience of query functions, and the intelligence of decision support. It not only optimizes the buyer experience but also improves the decision-making efficiency of managers, promoting the efficient and orderly development of the used car market. Attached Figure Description

[0031] Other features, objects, and advantages of the invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Figure 1 This is a schematic diagram of the modules of the used car entry and exit management system of the present invention; Figure 2 This is a schematic diagram of the used car entry process of the present invention; Figure 3 This is a flowchart illustrating the steps of the used car entry and exit management method of the present invention. Detailed Implementation

[0032] The present invention will be further described below with reference to the accompanying drawings and embodiments, but this should not be construed as limiting the present invention.

[0033] To achieve the above objectives, please refer to Figure 1-2 This invention provides a used car entry and exit management system, including the following modules: The vehicle RFID tag module is used to equip each used car with a unique encrypted RFID tag, which stores the vehicle identification number, initial entry time, preset price, and vehicle status information, and supports information exchange and status updates with the reading device. In this embodiment of the invention, each used car is equipped with a unique encrypted RFID tag. The tag adopts an ultra-high frequency passive design and is affixed to the upper right corner of the inside of the vehicle's windshield (without obstructing the driver's view). Core vehicle information is entered: a 17-digit vehicle identification number (LSVBD2A67MNXXXXXX), initial entry time (accurate to the second, e.g., 2024-12-01 09:15:30), preset selling price (92,000 yuan, accurate to the yuan), and initial vehicle status (awaiting entry). All information is processed using the AES-256 symmetric encryption algorithm to generate a 512-byte encrypted data block, which is stored in the tag's secure storage area (readable and writable only by authorized devices). The tag has a built-in communication chip that supports 915MHz fixed-frequency radio frequency signal interaction. After receiving status update commands (e.g., "sold" or "moving in progress") from the reading device, it automatically modifies the internal status field and records the operation timestamp. When responding to queries from the reading device, it only outputs the encrypted vehicle identification number. CRC32 verification ensures data transmission integrity, achieving secure information interaction and dynamic status updates with the reading device.

[0034] The intelligent electronic price tag module is used to bind an intelligent electronic price tag to each used car, receive and display basic vehicle information, real-time price and status, and has a built-in RFID reading unit that periodically scans surrounding tags to verify the consistency of identity and location and generate verification results. In this embodiment of the invention, a smart electronic price tag is attached to the vehicle. The price tag is fixed to the left front window of the vehicle by a clip and has a built-in 2.8-inch LCD display (480×320 resolution) and an RFID reading unit (detection frequency 915MHz, effective range radius of 2 meters). The price tag establishes a long connection with the market database via TCP / IP protocol (connection timeout time is 30 seconds), receives and synchronizes basic vehicle information (last 6 digits of vehicle identification number XXXXXX, model is Toyota Corolla 2021 1.5L Elite Edition), real-time price of 92,000 yuan, status "pending entry into inventory", and displays it according to a preset template: the upper area displays the model and vehicle condition level (A level), the middle area displays the selling price, and the lower area displays the status. The price tag activates its built-in RFID reading unit every 40 seconds, transmits radio frequency detection signals, receives encrypted response signals returned by the vehicle's RFID tag, decrypts the signals, extracts the vehicle identification number, and compares it digit by digit with the pre-stored binding identification number on the price tag. If all 17 characters match, a "verification passed" result is generated; otherwise, a "location abnormal" result is generated. All verification results, along with timestamps, are uploaded to the inventory monitoring module via a long connection.

[0035] The warehouse management module is used to collect tag information through the RFID reader at the entrance when vehicles enter the warehouse, complete vehicle information registration, vehicle condition verification, and price suggestion generation, and synchronize the warehouse data and price suggestions to the smart electronic price tag module. In this embodiment of the invention, when a vehicle enters the market entrance channel (marked with yellow guide lines on the ground), the RFID reader installed at the top of the channel (coverage radius of 3.5 meters, receiving sensitivity of -75dBm) is activated. The reader emits a 915MHz radio frequency signal, collects the encrypted information in the vehicle's RFID tag, calls the decryption algorithm to extract the vehicle identification number, and compares it with the market database to confirm the first entry into the warehouse. The vehicle condition verification process is then initiated: six high-definition cameras (resolution 2560×1440) on both sides of the channel collect images of the vehicle's exterior, identifying scratches, dents, and other defects; bottom sensors detect tire tread depth and the tightness of key chassis components. All data is input into the vehicle condition assessment model, which outputs an A-level vehicle condition rating (no accidents, minor scratches). The price generation model is then invoked, inputting the brand, model, vehicle condition, 3-year usage period, and market supply and demand parameters (28 vehicles of this model in stock, with an average monthly transaction volume of 15 vehicles), generating a suggested price of 92,000 yuan. The vehicle identification number, entry time, vehicle condition level, and suggested price are entered into the database to create an entry file. The core information is synchronized to the smart electronic price tag, and the price tag updates to "Status: In Stock" within 1 second, completing the synchronization and display update of the entry data.

[0036] The outbound management module is used to verify the tag information through the access control RFID reader when a vehicle leaves the site, and update the vehicle status to be sold or left. If a temporary relocation is required, the relocation time, target area and operator are recorded and synchronized to the smart electronic price tag module. In this embodiment of the invention, when a vehicle leaves after being sold, entering the exit channel triggers the activation of the access control RFID reader (coverage radius of 3 meters). The reader collects the encrypted information of the vehicle's RFID tag, decrypts it to extract the vehicle identification number, compares it with the "sold" vehicle list in the database, and issues a "sold" status update command. After receiving the command, the tag modifies its internal status field to "sold" and records the departure timestamp (2024-12-03 16:40:25). The reader uploads the departure information to the database, the database updates the vehicle status and synchronizes the command to the smart electronic price tag, and the price tag refreshes in real time to display "Status: Sold". If a vehicle needs to be temporarily moved to parking space number 15 in Zone C, the person making the move will initiate a move application via a handheld terminal. After approval, the area reader (installed at the entrance of Zone C) will read the tag information and issue a "Moving in progress" command. The tag will update its status, and the database will record the move time (2024-12-02 10:05:10), the target area (zone C, parking space number 15), and the operator's number (GL008). The information will be synchronized to the price tag, which will display "Status: Moving in progress". After the vehicle enters the target parking space, the area reader will scan the tag again, triggering a status update to "In stock".

[0037] The inventory monitoring and alarm module is used to receive the verification results of smart electronic price tags and vehicle inventory data from the database, to calculate the inventory quantity in real time, calculate the duration of slow sales, trigger alarms for inventory exceeding limits or slow sales exceeding time, and to locate abnormal vehicles by combining location information. In this embodiment of the invention, the inventory monitoring module receives the verification results uploaded by the smart electronic price tags in real time via the MQTT protocol (once every 40 seconds), and marks vehicles marked with "abnormal location" (such as price tags not being bound to tags) in red; it reads the vehicle inventory data from the database every 15 seconds via the JDBC interface, counts the current total number of vehicles in inventory as 210, compares it with the preset inventory upper limit threshold of 200 vehicles, and generates an inventory over-limit alarm (10 vehicles exceeding the limit). It calculates the unsold duration of each vehicle in inventory (the difference between the current time and the entry time). For example, if the vehicle identification number LSVCE2A89PNXXXXXX was entered on 2024-09-01 and has an unsold duration of 91 days, exceeding the preset threshold of 90 days, an unsold over-time alarm is generated (including the identification number, unsold duration, and current price of 88,000 yuan). By combining the location data fed back from the multi-point RFID positioning network, the precise coordinates (e.g., X72.3 meters, Y45.6 meters) of abnormal vehicles (abnormal location, excess inventory, slow-moving vehicles) are locked. The alarm information is associated with the location coordinates and pushed to the management terminal (computer and mobile APP) via the WebSocket protocol.

[0038] The multi-point RFID positioning network module is used to deploy dense RFID reader nodes in the market, collect the tag signal strength received by each node, calculate the precise coordinates of the vehicle through the triangulation algorithm, and output positioning data. In this embodiment of the invention, 150 RFID reader nodes are deployed within the market at a density of one node every 15 meters in passageways, one node every 200 square meters in parking areas, and two nodes each at entrances and exits. Each node has a built-in GPS chip and pre-stores precise coordinates (e.g., node C12 coordinates X65 meters, Y38 meters, error ≤0.1 meters). Each node is continuously in signal receiving mode (receiving frequency 915MHz), collecting radio frequency signals emitted by RFID tags of surrounding vehicles in real time, recording signal strength values ​​(unit dBm, e.g., -58dBm), its own coordinates, and receiving timestamps. Every second, the data is packaged into positioning data frames and uploaded to the positioning calculation unit. The calculation unit receives valid data frames (signal strength > -75dBm) from at least three nodes within one second for the same vehicle, and normalizes the signal strength values ​​using the Min-Max scaling method to eliminate hardware difference errors. Using the coordinates of three nodes as vertices, the normalized signal strength is converted into the corresponding distance (e.g., -58dBm corresponds to 6 meters) as the side length to construct a positioning triangle. The triangulation algorithm is used to calculate the centroid coordinates of the triangle, and the signal strength weight (the higher the strength, the greater the weight) is combined for correction to obtain the precise coordinates of the vehicle (e.g., X 66.8 meters, Y 39.2 meters). The output includes positioning data containing the vehicle identification number, coordinates, and timestamp.

[0039] The inventory map visualization module receives location data and vehicle status information, generates a real-time inventory distribution map, supports buyer queries and optimal vehicle viewing route planning, and provides managers with a basis for scheduling and site planning decisions.

[0040] In this embodiment of the invention, the inventory map visualization module receives location data and vehicle status information (in stock / sold / moving), and generates a 1:200 scale real-time market inventory distribution map. The map is divided into areas (A / B / C / D zones), and different colors are used to mark vehicle status (green for in stock, red for sold, and yellow for moving). Clicking on a vehicle marker on the map displays detailed information (identification number, model, price, vehicle condition, and entry time). Buyers can input their target vehicle model (Toyota Corolla) through the market query terminal. The system retrieves 5 in stock vehicles from the database and, combined with the buyer's current location (entrance reception area X10 meters, Y15 meters), uses Dijkstra's algorithm to calculate the optimal viewing route (entrance → A zone passage → C zone parking space 15, total distance 68 meters, estimated time 3 minutes). The route is marked on the map with blue lines and includes navigation prompts. Generate data reports for managers: total inventory of 210 vehicles, parking space utilization rate in each area (Area A 92%, Area B 85%, Area C 78%, Area D 65%), 12 unsold vehicles, and provide scheduling suggestions (move 10 vehicles from Area A to Area D) and site planning basis (15 additional parking spaces can be added in Area C) to support management decisions.

[0041] Furthermore, the vehicle RFID tag module includes the following functions: Each used car is assigned a unique identification tag, and basic information such as vehicle identification number, year of manufacture, model configuration, and initial vehicle condition level is entered into the tag; The entered basic information is encrypted using a symmetric encryption algorithm, and the encrypted core data block is stored in the secure storage area of ​​the RFID tag. When a vehicle enters the site, it establishes a communication connection with the RFID reader at the entrance, receives the entry timestamp sent by the reader, and updates the entry status in the tag to pending confirmation. When a vehicle leaves or is moved, it interacts with the access control or area reader to receive a status update instruction and changes the vehicle status in the tag to sold, departed, or being moved. It regularly responds to scanning requests from the built-in reading unit of the smart electronic price tag, outputs encrypted identity information for verification, and ensures that the binding relationship between the tag and the vehicle is not tampered with.

[0042] In this embodiment of the invention, the vehicle RFID tag module assigns a unique identifier to each used car. This identifier corresponds one-to-one with the vehicle identification number (VIN). Basic information corresponding to the VIN (17 characters, e.g., LSVAF2A45LNXXXXXX), production year (4 digits, e.g., 2020), vehicle configuration (e.g., Volkswagen Lavida 2020 1.5L Automatic Comfort Edition), and initial vehicle condition level (3-level classification, e.g., Class B) is entered into the tag. The entered basic information is encrypted using the AES-256 symmetric encryption algorithm. The encryption key is uniformly generated and stored by the market management system, generating a fixed-length 512-byte encrypted core data block, which is stored in the secure storage area of ​​the RFID tag. This storage area only supports read and write operations by authorized devices and prohibits unauthorized access. When a vehicle enters the facility, the RFID tag establishes a communication connection with the RFID reader at the entrance via radio frequency communication technology. The communication frequency is fixed at 915MHz. The reader sends an entry timestamp accurate to the second (e.g., 2024-11-25 09:30:45). Upon receiving this, the tag automatically updates its internally stored entry status field to "Pending Confirmation" and records the timestamp information synchronously. When a vehicle leaves the facility or is moved, the tag enters the signal coverage area (3-meter radius) of the access control or area reader and receives a status update command from the reader. If it is a sales exit, the vehicle status is changed to "Sold"; if it is a move out of the market, it is changed to "Departed"; if it is a move within the facility, it is changed to "Moving in Progress". The status change record includes the operation timestamp and the reader identifier. The tag responds to the scanning request from the built-in reading unit of the smart electronic price tag at a fixed 60-second interval. When responding, it only outputs encrypted identity information (encrypted vehicle identification number data) for verification. The data signature mechanism ensures that it is not tampered with during transmission. After each response, the internal verification counter is automatically updated to prevent duplicate verification attacks and ensure that the binding relationship between the tag and the vehicle is always valid.

[0043] Furthermore, the intelligent electronic price tag module includes the following functions: Receive vehicle basic information, price suggestions and inventory status synchronized from the inventory management module, convert the data into a standardized display format, and display the vehicle identification number, price, vehicle condition level and inventory status in the price tag screen in sections; The built-in RFID reading unit is activated according to the preset scanning cycle, and a fixed frequency radio frequency detection signal is emitted to the surrounding area; The system receives encrypted response signals from RFID tags on vehicles within its range, amplifies and filters the signals, and extracts encrypted identity information. The decryption algorithm is called to decrypt the encrypted identity information to obtain the target vehicle identification number. The target vehicle identification number is then compared field by field with the vehicle identification number bound to the target vehicle to generate an identity and location consistency verification result. It establishes a long-term connection with the market management database in real time, receives update instructions such as price adjustments and status changes issued by the database, refreshes the price tag display content synchronously, and uploads the verification results and update status to the inventory monitoring and alarm module.

[0044] In this embodiment of the invention, the intelligent electronic price tag module receives vehicle basic information (vehicle identification number, production year, model configuration), price suggestions (accurate to yuan, such as 85,000 yuan), and inventory status (pending confirmation) synchronized by the inventory management module via a wired network. The module converts the data into a standardized display format using a format conversion algorithm and displays it in sections on the price tag's 2.4-inch LCD screen: the upper section displays the last 6 digits of the vehicle identification number (XXXXXX) and the selling price; the middle section displays the vehicle condition level (Class B) and model configuration; and the lower section displays the inventory status (pending confirmation). The font size is fixed at 12pt to ensure clear readability. The price tag activates its built-in RFID reading unit according to a preset 30-second scanning cycle. The reading unit transmits a fixed 915MHz radio frequency detection signal with a signal transmission power controlled at 10dBm and a detection range radius limited to 2 meters to avoid cross-regional interference. The price tag receives encrypted response signals from RFID tags on vehicles within its receiving range. The built-in signal processing circuit amplifies the signal (100x amplification) and filters it (using a low-pass filter with a 1MHz cutoff frequency) to remove environmental electromagnetic interference, extracting the encrypted identity information (512 bytes of encrypted data). The price tag then calls the AES-256 decryption algorithm corresponding to the RFID tag, using a pre-stored decryption key to decrypt the encrypted identity information, obtaining the target vehicle identification number. This number is then compared field-by-field with the vehicle identification number bound to the price tag (stored in internal non-volatile storage), verifying character consistency from the 1st to the 17th character, generating an identity and location consistency verification result (consistency indicates success, inconsistency indicates an error). The price tag establishes a long connection with the market management database via TCP / IP protocol, with a connection timeout set to 30 seconds. It receives update instructions from the database in real time, such as price adjustments (e.g., adjusted to 83,000 yuan) and status changes (e.g., changed from pending confirmation to in stock). Upon receiving the instruction, the screen display is refreshed synchronously within 1 second, and the verification result (pass / abnormal) and update status (update successful / failed) are uploaded to the inventory monitoring and alarm module via the long connection to ensure real-time data synchronization.

[0045] Furthermore, the step of activating the built-in RFID reading unit to scan surrounding tags according to a preset cycle includes: The system reads the preset scanning cycle parameters from the smart electronic price tag, which are dynamically adjusted by the system based on the market vehicle density. When the scanning time point is reached, the transmitting circuit of the built-in RFID reading unit is activated, generating a radio frequency detection signal that conforms to the ISO standard and transmitting it to a preset radius range centered on the price tag; The system receives response signals from RFID tags of vehicles within its range, performs noise reduction and shaping on the signals, and removes noise caused by environmental interference and signal attenuation. The processed valid signal is converted into a digital signal stream, and the encrypted identity information field and signal strength value are parsed out according to the communication protocol of the RFID tag; The encrypted identity information is parsed and its integrity is verified. The data length and check bits are checked to see if they meet the preset specifications, and valid identity information is filtered out. The system compares the valid identity information with the vehicle identification number bound to it. If they match, a verification result is generated. If they do not match or no matching tag is detected, an error message is generated and synchronized to the inventory monitoring and alarm module.

[0046] In this embodiment of the invention, when the smart electronic price tag initiates the scanning process, it first reads the preset scanning cycle parameter from the internal non-volatile storage area. This parameter is dynamically adjusted by the market management system based on the vehicle density within the market. The cycle is set to 20 seconds when the vehicle density is ≥5 vehicles / 10 square meters, and 40 seconds when the density is <5 vehicles / 10 square meters. The current preset cycle is 30 seconds. Upon reaching the scanning time point, the price tag's internal controller activates the transmitting circuit of the built-in RFID reading unit. The transmitting circuit generates a radio frequency detection signal conforming to the ISO18000-6C standard, using amplitude shift keying modulation, with a center frequency of 915MHz and a transmission duration of 1 second, uniformly transmitting the signal within a preset range of 2 meters centered on the price tag. The price tag's receiving antenna receives response signals from the RFID tags of each vehicle within its range. The built-in signal processing module performs noise reduction (using an adaptive noise cancellation algorithm) and shaping (converting the analog signal into a square wave using a comparator) on the signals, removing noise caused by environmental electromagnetic interference and signal attenuation, and retaining the effective signal. The processed analog valid signal is converted into an 8-bit digital signal stream using an analog-to-digital converter. The digital signal stream is parsed according to the RFID tag communication protocol (ISO18000-6C) to extract the encrypted identity information field (512 bytes) and the signal strength value (in dBm, ranging from -60dBm to -30dBm). Signal strength values ​​below -60dBm are considered invalid and discarded. The parsed encrypted identity information undergoes integrity verification, checking if the data length is strictly 512 bytes and if the checksum is consistent with the result calculated using the CRC32 algorithm. If both requirements are met, the information is considered valid. The valid identity information is decrypted to obtain the vehicle identification number (VIN) and compared character-by-character with the VIN bound to the price tag. If all 17 characters match, a verification pass result is generated. If they do not match or no matching tag is detected (no valid identity information returned), an error message is generated, including the price tag number, scan timestamp, and signal strength value (marked as 0 when there is no signal). This message is simultaneously uploaded to the inventory monitoring and alarm module, triggering a location anomaly warning.

[0047] Furthermore, the integrity verification of the parsed encrypted identity information includes: Extract the data length field from the parsed encrypted identity information and compare it with the system's preset standard data length; If the data lengths are consistent, extract the cyclic redundancy check code at the end of the information and perform cyclic redundancy check calculation on the entire encrypted data block. The calculated check code is compared with the extracted check code to determine whether there is any loss or tampering during data transmission. If the verification code matches, further verify the format identifier bit of the encrypted data block to confirm that the data conforms to the tag's storage format specification; Generate integrity verification results. If all verification items pass, the data is marked as valid identity information; otherwise, it is marked as invalid data and discarded. Valid identity information is transmitted to the next comparison process, while the reception time and signal strength information of invalid data are recorded for subsequent positioning network optimization.

[0048] In this embodiment of the invention, when performing integrity verification on the parsed encrypted identity information, the first two bytes of the data length field are extracted from the parsed 512-byte encrypted identity information. This field stores the hexadecimal value of the total data length (0x0200 corresponds to 512 bytes), which is compared with the system's preset standard data length of 512 bytes to confirm that the values ​​are consistent. If the data lengths are consistent, the last four bytes of the information are extracted as a Cyclic Redundancy Check (CRC32 checksum). The CRC32 algorithm is used to perform verification calculations on the entire 512-byte encrypted data block (including the data length field, the encrypted identity information body, and the checksum field). The initial value during the calculation is set to 0xFFFFFFFF, and the polynomial is 0xEDB88320, ultimately yielding a 32-bit verification result. The calculated checksum is compared bit by bit with the extracted last checksum. If the 8 hexadecimal values ​​are exactly the same (e.g., both are 0x12345678), it is determined that there was no loss or tampering during data transmission; if there are differences, it is determined that the data is corrupted. After the verification code matches, the format identifier bits of bytes 3-4 of the encrypted data block are further verified. The default value of this identifier bit is 0x5A5A. Confirming that the identifier bit value matches the default value ensures that the data conforms to the secure storage format specification of RFID tags (2-byte length in the data block header, 2-byte format identifier, 502-byte encrypted body, and 4-byte verification code). An integrity verification result is generated. If all verification items (length, verification code, and format identifier) ​​pass, the data is marked as valid identity information. If any item fails (e.g., length field is 0x01FF corresponding to 511 bytes, verification code difference, or format identifier is 0x5A5B), the data is marked as invalid and discarded. The valid identity information is then transmitted to the vehicle identification number comparison process. Simultaneously, the reception time of invalid data (accurate to the second, e.g., 2024-11-25 10:15:30) and signal strength value (e.g., -55dBm) are recorded and stored in the system log database for subsequent analysis of RFID signal interference areas and optimization of reader layout and signal strength parameters in the multi-point RFID positioning network.

[0049] Furthermore, the warehousing management module includes the following functions: When a vehicle enters the market entrance, it triggers the RFID reader at the entrance to read the encrypted basic information in the vehicle's RFID tag. The encrypted basic information is decrypted, the vehicle identification number is extracted, and compared with the vehicle information already registered in the market database to determine whether it is the first time it has entered the database. If it is the first time the vehicle is put into the warehouse, the vehicle condition verification process will be initiated. High-definition cameras will be used to collect images of the vehicle's exterior, sensors will be used to detect the status of key components, and a vehicle condition level assessment result will be generated. Call the price generation model, input the vehicle brand, model, vehicle condition level, years of use, and market supply and demand parameters, and generate an initial price suggestion; Enter the vehicle identification number, entry time, vehicle condition level, and suggested price information into the market database to create a vehicle entry file; The core display information in the inbound file is synchronized to the corresponding smart electronic price tag module, triggering a price tag display update, and the vehicle status is set to in stock.

[0050] In this embodiment of the invention, when the warehousing management module is in operation, when a used car enters the designated area at the market entrance (entrance passage area 1, marked with a yellow border on the ground), the RFID reader installed at the top of the passage is activated. The reader emits a 915MHz radio frequency signal, covering a radius of 3 meters, and reads the 512 bytes of encrypted basic information stored in the vehicle's RFID tag. The reader calls the AES-256 decryption algorithm and uses a pre-stored decryption key (consistent with the tag's encryption key) to decrypt the encrypted basic information, extracting the 17-digit vehicle identification number (e.g., LSVAF2A45LNXXXXXX). The vehicle identification number is then sent to the market management database via the TCP / IP protocol and compared character by character with the list of registered vehicle identification numbers in the database. If the comparison result shows that the vehicle identification number does not exist in the list, it is determined to be the first time the vehicle has entered the market. The vehicle condition verification process begins: Four high-definition cameras (1920×1080 resolution, 30fps) installed on both sides of the passage capture exterior images of the vehicle from four angles: front, rear, left, and right. Image processing algorithms identify scratches, dents, and other defects. Simultaneously, key component detection sensors installed at the bottom of the passage (covering wheels and key chassis connection points) detect tire wear and chassis component tightness. The image analysis results and sensor data are input into the vehicle condition assessment model, which outputs a vehicle condition rating (Level B, corresponding to "no major accidents, minor exterior defects"). The price generation model is then invoked, inputting the vehicle brand (Volkswagen), model (2020 Lavida 1.5L Automatic Comfort Edition), vehicle condition rating (Level B), years of use (4 years), and market supply and demand parameters (current market inventory of this model is 35 units, average monthly sales volume is 12 units). The model uses a linear regression algorithm to calculate and generate an initial price suggestion (85,000 yuan, accurate to the yuan). The vehicle identification number, entry time (2024-11-25 10:20:15), vehicle condition level (Class B), and suggested price (85,000 yuan) are entered into the market database. A vehicle entry file containing basic vehicle information, verification records, and price information is created, and a file number is automatically generated (e.g., RK20241125001). The core display information in the entry file (last 6 digits of the vehicle identification number, Class B vehicle condition level, vehicle configuration, price 85,000 yuan, and status "in stock") is synchronized to the corresponding smart electronic price tag module (price tag number JQ001) through the data synchronization interface. This triggers the price tag LCD screen to refresh the displayed content within 1 second, and at the same time, the vehicle status field is set to "in stock" in the database, completing the entry process.

[0051] Furthermore, the inventory monitoring and alarm module includes the following functions: The system reads the entry time, current status, and price information of all vehicles in the market database in real time to create a dynamic inventory list. Receive the identity and location consistency verification results uploaded by the smart electronic price tag module, and mark the vehicles marked as abnormal separately; The total number of vehicles in the dynamic inventory list that are in stock is counted and compared with the system's preset inventory upper limit threshold. Calculate the unsold duration of each vehicle in the warehouse, which is the difference between the current time and the time of entry into the warehouse, and compare it with the preset unsold duration threshold. If the total inventory exceeds the upper limit threshold, an inventory over-limit alarm message will be generated, including the current inventory quantity, the over-limit difference, and the suggested scheduling direction; If there are vehicles whose unsold period exceeds the threshold, an unsold period alarm message will be generated, which includes the vehicle identification number, unsold period, and current price. It receives positioning data from a multi-point RFID positioning network module, associates the location information of abnormal vehicles, over-limit inventory vehicles, and slow-selling vehicles with alarm information, and generates a comprehensive alarm notification to send to the management terminal.

[0052] In this embodiment of the invention, the inventory monitoring and alarm module reads the entry time, current status (in stock / sold / departed / transferred) and price information of all vehicles in real time from the market management database via a JDBC interface. The reading frequency is set to once every 10 seconds. A dynamic inventory list containing vehicle identification number, entry time, status, price, and corresponding price tag number is established. The list is updated in real time and stored in the module's memory. The module receives the identity and location consistency verification results uploaded by the smart electronic price tag module via the MQTT protocol every 30 seconds. Vehicles marked as "abnormal" by the verification result (such as price tag JQ002 being bound to a vehicle without a matching tag, price tag JQ005 being found to have a non-bound tag) are individually marked and distinguished in red in the dynamic inventory list. The total number of vehicles with the status "in stock" in the dynamic inventory list is counted. The current count is 185 vehicles, which is compared with the system's preset inventory upper limit threshold of 200 vehicles, confirming that it is within the limit. If the subsequent count is 205 vehicles, the difference between the two is 5 vehicles. Calculate the unsold duration for each vehicle in inventory, which is the difference between the current time (2024-11-25 14:30:00) and the entry time. For example, if vehicle identification number LSVAF2A45LNXXXXXX was entered on 2024-09-20 11:00:00, the unsold duration is 66 days. Compare this with the preset unsold duration threshold of 90 days to confirm that it has not exceeded the time limit. If a vehicle's unsold duration is 95 days, it is determined to have exceeded the time limit. If the total inventory exceeds the upper limit threshold (e.g., 205 vehicles), generate an inventory over-limit alarm message, including the current inventory quantity of 205 vehicles, the over-limit difference of 5 vehicles, and a suggested dispatch direction (dispatch 10 family cars to the East City branch). The alarm message format is JSON, including alarm type, value, and suggestion fields. If any vehicle has been unsold for more than a threshold period (e.g., 95 days), an overdue unsold alarm will be generated, including the vehicle identification number (e.g., LSVBD2A67MNXXXXXX), the unsold period of 95 days, the current price of 78,000 yuan, and the vehicle's inquiry records for the past 30 days (2 times). The system receives positioning data (including vehicle identification number, X / Y coordinates, and positioning accuracy) transmitted via UDP from the multi-point RFID positioning network module. It associates the location information (e.g., X: 15.2 meters, Y: 8.7 meters, accuracy ±0.5 meters) of abnormal vehicles (vehicles corresponding to price tag JQ002), vehicles with excess inventory (if any), and unsold vehicles (LSVBD2A67MNXXXXXX) with the alarm information, generating a comprehensive alarm notification. This notification is sent in real-time to the management terminal (computer or mobile app) via the WebSocket protocol, including a text description, location map markers, and processing priority (high / medium / low).

[0053] Furthermore, the multi-point RFID positioning network module includes the following functions: High-density RFID reader nodes are deployed at key locations such as intersections, parking areas, and entrances / exits within the market. Each node has a built-in location coordinate chip. Each reader node is continuously in signal receiving mode, collecting radio frequency signals emitted by RFID tags of surrounding vehicles in real time, and recording the signal reception time and signal strength value; Each node packages the collected signal strength value, its own location coordinates, and the signal reception timestamp into a positioning data frame, and uploads it to the positioning computing unit through the wireless communication network. The positioning calculation unit receives positioning data frames from multiple nodes for the same vehicle within the same time period and filters out valid data frames with signal strength greater than a threshold. The signal strength values ​​in the valid data frames are normalized to eliminate errors caused by hardware differences between different nodes; The triangulation algorithm is used to construct a positioning triangle with the coordinates of each node as the vertices and the distance corresponding to the normalized signal strength as the side length. The centroid coordinates of the positioning triangle are calculated and corrected using a signal strength weighting factor to obtain the precise position coordinates of the vehicle. The precise location coordinates are checked for boundaries to ensure that they fall within the pre-defined geographical area of ​​the market, generating valid location data and feeding it back to the inventory monitoring and alarm module and the inventory map visualization module.

[0054] In this embodiment of the invention, a multi-point RFID positioning network module deploys high-density RFID reader nodes within the used car market according to the principle of "full coverage of key nodes." One node is deployed every 20 meters at intersections (e.g., nodes A1-A15), one node is deployed at the center of each parking space area (e.g., nodes P1-P80), and two nodes are deployed on each side of the entrances and exits (e.g., nodes E1-E4), for a total of 120 nodes. Each node has a built-in GPS location coordinate chip and pre-stores precise coordinates (e.g., coordinates of node A5: X: 50 meters, Y: 30 meters, error ≤ 0.1 meters). Each reader node is continuously in signal receiving mode, with a fixed receiving frequency of 915MHz and a signal receiving sensitivity set to -70dBm. It collects radio frequency signals emitted by RFID tags from surrounding vehicles in real time, recording the signal reception time (accurate to milliseconds, e.g., 2024-11-25 15:40:00.123) and signal strength value (in dBm, e.g., -52dBm, -65dBm) every second. Each node packages the collected signal strength value, its pre-stored location coordinates, and signal reception timestamp into a positioning data frame. The data frame format is "node number + X coordinate + Y coordinate + signal strength + timestamp" (e.g., A5,50,30,-52,20241125154000123). This data frame is uploaded to the positioning calculation unit via a LoRa wireless communication network (transmission rate 50kbps, communication distance 100 meters) at 1-second intervals. The positioning calculation unit receives positioning data frames from the same vehicle (identification number LSVAF2A45LNXXXXXX) from nodes A5, P12, and E2 within a 1-second time period. It then filters out valid data frames with signal strength greater than the -70dBm threshold (valid for A5 node -52dBm and P12 node -60dBm, invalid for E2 node -72dBm). The signal strength values ​​in the valid data frames are normalized. The Min-Max scaling method is used to convert -52dBm at node A5 to 0.8 and -60dBm at node P12 to 0.6, eliminating errors caused by hardware differences between nodes. A triangulation algorithm is employed, using the position coordinates of node A5 (X50, Y30), node P12 (X60, Y45), and the backup node A6 (X40, Y40) as vertices, and the distances corresponding to the normalized signal strengths (0.8 corresponds to 5 meters, and 0.6 corresponds to 8 meters) as side lengths to construct a positioning triangle. The centroid coordinates of the positioning triangle are calculated as (X(50+60+40) / 3, Y(30+45+40) / 3) = (X50, Y38.33). After correction by combining the signal strength weight factors (A5 node weight 0.5, P12 node weight 0.3, A6 node weight 0.2), the precise vehicle position coordinates are obtained as (X50×0.5+60×0.3+40×0.2, Y30×0.5+45×0.3+40×0.2) = (X51, Y35.5).The precise location coordinates are checked for boundaries to confirm that X51 meters and Y35.5 meters fall within the preset geographical range of the market (X0-X100 meters, Y0-Y80 meters). Valid location data containing vehicle identification number, precise coordinates, and calculation timestamp is generated and fed back to the inventory monitoring and alarm module and the inventory map visualization module via TCP / IP protocol.

[0055] Furthermore, the calculation of the vehicle's precise position coordinates using the triangulation algorithm includes: Extract the position coordinates of at least three different nodes and their corresponding normalized signal strength values ​​from the valid data frame; Based on the radio frequency signal propagation attenuation model, the normalized signal strength value of each node is converted into the straight-line distance from the vehicle to that node; Establish a two-dimensional rectangular coordinate system with the position coordinates of the first node as the origin, and convert the position coordinates of other nodes into coordinate values ​​in this coordinate system; Based on the coordinates and corresponding distances of the three nodes, three sets of distance equations are listed to form a system of equations; The system of equations is solved using the least squares method to obtain the initial coordinates of the vehicle in this coordinate system. The initial coordinate values ​​are converted into market-standard geographic coordinates to obtain preliminary positioning coordinates; Extract the vehicle's historical positioning data, calculate the deviation between the preliminary positioning coordinates and the historical coordinates, and perform smoothing if the deviation exceeds a preset threshold. By combining the signal strength weights of each node, the initial positioning coordinates are weighted and corrected to generate the final accurate position coordinates; The precise location coordinates are associated with the node number and the calculation timestamp to form a complete location data record.

[0056] In this embodiment of the invention, when calculating the precise position coordinates of the vehicle using a triangulation algorithm, the position coordinates and corresponding normalized signal strength values ​​of three different nodes, A5, P12, and A6, are first extracted from the valid data frame: node A5 (X50, Y30, normalized strength 0.8), node P12 (X60, Y45, normalized strength 0.6), and node A6 (X40, Y40, normalized strength 0.7). Based on the radio frequency signal propagation attenuation model (for every 6dBm decrease in signal strength, the distance doubles), the normalized signal strength value of each node is converted into the straight-line distance from the vehicle to that node: node A5 (0.8) corresponds to 5 meters (reference distance 5 meters, normalized strength 1.0 corresponds to 5 meters), node P12 (0.6) corresponds to 8 meters, and node A6 (0.7) corresponds to 6.5 meters. Establish a two-dimensional rectangular coordinate system with the position coordinates (X50, Y30) of the first node A5 as the origin. The X-axis is positive to the right, and the Y-axis is positive upwards. Convert the position coordinates of other nodes to coordinates in this system: node P12 is converted to (X60-50, Y45-30) = (X10, Y15), and node A6 is converted to (X40-50, Y40-30) = (X-10, Y10). Based on the coordinate values ​​of the three nodes and their corresponding distance values, list three sets of distance equations: the distance equation from the vehicle coordinates (x, y) to node A5 is x 2 +y 2 =5 2 (25); Equation for distance to node P12 (x-10) 2 + (y-15) 2 =8 2 (64); Distance equation to node A6 (x+10) 2 + (y-10) 2 =6.5 2 (42.25), forming a system of equations. Solving the system of equations using the least squares method, expanding the first equation yields x. 2 +y 2 =25, the second equation gives x 2 -20x+100+y 2 -30y + 225 = 64. Substituting the first equation into the second equation, we get -20x - 30y + 325 = 64 → 20x + 30y = 261 → 2x + 3y = 26.1; Expanding the third equation, we get x 2+20x+100+y²-20y+100=42.25, substituting into the first equation, we get 20x-20y+200=42.25→20x-20y=-157.75→4x-4y=-31.55. Solving the two linear equations simultaneously, we get x = (26.1 - 3y) / 2 from 2x + 3y = 26.1. Substituting this into 4x - 4y = -31.55, we get 4 × (26.1 - 3y) / 2 - 4y = -31.55 → 2 × (26.1 - 3y) - 4y = -31.55 → 52.2 - 6y - 4y = -31.55 → -10y = -83.75 → y = 8.375. Therefore, x = (26.1 - 3 × 8.375) / 2 = (26.1 - 25.125) / 2 = 0.975 / 2 = 0.4875. This gives us the initial coordinates of the vehicle in this coordinate system: (x 0.4875, y 8.375). The initial coordinates are converted to a market-standard geographic coordinate system: x0.4875 + 50 = X50.4875, y8.375 + 30 = Y38.375, resulting in preliminary positioning coordinates (X50.49, Y38.38, rounded to two decimal places). The vehicle's past 10 historical positioning data points are extracted (e.g., the most recent is X50.52, Y38.40), and the deviation between the preliminary positioning coordinates and the historical coordinates is calculated (ΔX0.03, ΔY0.02). Since the deviation is less than a preset threshold of 0.5 meters, no smoothing is required. By combining the signal strength weights of each node (A5 node 0.5, P12 node 0.3, A6 node 0.2), the initial positioning coordinates are weighted and corrected: X5 0.49×0.5+60×0.3+40×0.2=X51.245→X51.25, Y38.38×0.5+45×0.3+40×0.2=Y39.19→Y39.19, generating the final precise location coordinates (X51.25, Y39.19). These precise location coordinates are then associated with the node numbers (A5, P12, A6) and the calculation timestamp (2024-11-25 15:40:01.567) to form a complete positioning data record, which is stored in the positioning database and synchronized to the inventory map module.

[0057] Furthermore, Embodiment 2 of the present invention also provides a method for managing the entry and exit of used cars, such as... Figure 3 As shown, the method is implemented based on the used car inbound and outbound management system described above, and the used car inbound and outbound management method includes the following steps: Step S01: Install a unique encrypted RFID tag on each used car, enter the basic vehicle information and store it encrypted, and complete the binding of the tag to the vehicle; In this embodiment of the invention, a unique encrypted RFID tag is installed on each used car. The tag is an ultra-high frequency passive type and is affixed to the upper left corner of the inside of the vehicle's windshield (out of sight). Basic vehicle information is entered: a 17-digit vehicle identification number (LSVAF2A45LNXXXXXX), production year 2020, vehicle configuration (Volkswagen Lavida 2020 1.5L Automatic Comfort Edition), and initial vehicle condition level B (no major accidents, minor exterior defects). The basic information is encrypted using the AES-256 symmetric encryption algorithm. The encryption key is generated by the market management system and stored separately. A 512-byte encrypted data block is generated and stored in the tag's secure storage area (readable and writable only by authorized devices). A dedicated activation device emits a 915MHz radio frequency signal to trigger the tag's internal binding program, associating the tag's unique ID with the vehicle identification number one-to-one. The association record is stored in the market database, completing the binding between the tag and the vehicle. After binding, the tag only responds to authentication requests corresponding to that vehicle.

[0058] Step S02: Bind the smart electronic price tag to the vehicle, establish a communication connection between the price tag, RFID tag, and market database, and complete the initial information synchronization and display; In this embodiment of the invention, a smart electronic price tag, numbered JQ001, is attached to the vehicle and fixed to the right side of the front windshield via a wired connection. The price tag incorporates an RFID reading unit (915MHz receiving frequency, 2-meter detection radius) and an LCD display (2.4 inches, 320×240 resolution). A communication connection is established between the price tag and the RFID tag: the price tag emits a detection signal, receives encrypted identity information returned by the tag, decrypts it, extracts the vehicle identification number, and compares it with the pre-stored vehicle identification number on the price tag to complete the communication pairing. A long-term connection (30-second timeout) is established between the price tag and the market database via TCP / IP protocol, synchronizing basic vehicle information (last 6 digits of the identification number, vehicle model, and vehicle condition level) and an initial suggested price of 85,000 yuan. The price tag converts the data into a standardized format and displays it in four sections on the screen: the upper section displays "Volkswagen Lavida 2020 B-Class," the middle section displays "Price: 85,000 yuan," and the lower section displays "Status: Pending Entry," completing the initial information synchronization and display.

[0059] Step S03: When a vehicle enters the parking lot, the RFID reader at the entrance collects the tag information, completes the vehicle condition verification and price suggestion generation, registers the vehicle in the storage file and updates the price tag display; In this embodiment of the invention, when a vehicle enters the market entrance channel, it triggers the activation of the RFID reader at the top of the channel (coverage radius of 3 meters, receiving sensitivity of -70dBm). The reader emits a 915MHz radio frequency signal, collects the encrypted basic information in the vehicle's RFID tag, decrypts it using the AES-256 algorithm, extracts the vehicle identification number, and compares it with the market database to confirm the first entry into the warehouse. The vehicle condition verification process then begins: four high-definition cameras (1920×1080 resolution) on both sides of the channel collect images of the vehicle's exterior, and bottom sensors detect tire wear and chassis component condition. The images and detection data are input into the vehicle condition assessment model, which outputs a Grade B assessment result. The price generation model is then invoked, inputting the brand, model, vehicle condition, 4-year service life, and market supply and demand parameters (35 vehicles in stock for this model, with an average monthly transaction volume of 12 vehicles), generating an initial price suggestion of 85,000 yuan. Enter the vehicle identification number, entry time (2024-11-25 10:20:15), vehicle condition level, and suggested price into the market database to create an entry file (number RK20241125001). Synchronize the core information to the price tag JQ001. The price tag will update to show "Status: In Stock" within 1 second, completing the entry registration.

[0060] Step S04: The smart electronic price tag periodically scans the tags to generate verification results, the positioning network calculates the precise location of the vehicle, and the monitoring module counts inventory and unsold goods and triggers an alarm. In this embodiment of the invention, the intelligent electronic price tag JQ001 activates its built-in RFID reading unit every 30 seconds, transmits a detection signal to receive the vehicle's RFID tag response, decrypts and extracts the identification number, compares it with its own bound identification number, generates a "consistent" verification result, and uploads it to the inventory monitoring and alarm module every 30 seconds. In a multi-point RFID positioning network (120 nodes deployed in passageways, parking spaces, and entrances / exits), nodes A5 (X50, Y30), P12 (X60, Y45), and A6 (X40, Y40) collect vehicle tag signals, upload positioning data frames to the calculation unit, and calculate the precise vehicle coordinates (X51.25, Y39.19) using Min-Max normalization and triangulation algorithms, which are then fed back to the monitoring module and the inventory map module. The monitoring module reads database data in real time, counts 185 vehicles in stock (not exceeding the 200-vehicle limit), calculates the unsold duration of each vehicle (0 days as of November 25, not exceeding the 90-day threshold), and triggers no alarms. If a vehicle is unsold for 95 days, an unsold alarm is generated (including identification number, duration, and price), and the vehicle's location information is synchronized to the management terminal.

[0061] Step S05: When a vehicle leaves the premises, the tag information is verified by the access control reader, and the status is updated to "sold" or "departed"; when a temporary transfer occurs, the transfer information is recorded and synchronized to the price tag and the database; In this embodiment of the invention, after a vehicle is sold and leaves the premises, it enters the exit channel, triggering the activation of the access control RFID reader (coverage radius of 3 meters). The reader reads the encrypted information of the vehicle's RFID tag, decrypts and extracts the identification number, and compares it with the "sold" vehicle list in the database. If they match, the reader issues a "sold" status update command. Upon receiving the command, the tag modifies its internal status field to "sold" and records the departure timestamp (2024-11-28 15:30:20). The reader uploads the departure information to the market database, which updates the vehicle status to "sold." A synchronized command is sent to the smart electronic price tag JQ001, and the price tag updates its display to "Status: Sold" within 1 second. If a vehicle needs to be temporarily moved to a parking space in Zone B, the area reader (node ​​P25) will read the tag information during the move and issue a "Moving in progress" command. The tag will update its status, and the database will record the move time (2024-11-26 09:10:05) and the target location (parking space No. 12 in Zone B). The price tag will simultaneously display "Status: Moving in progress". After the move is completed, the area reader will trigger a status update to "In stock".

[0062] Step S06: Generate an inventory map based on location data and vehicle status, supporting querying and route planning, and providing data support for management decisions.

[0063] In this embodiment of the invention, the inventory map visualization module generates a market-level inventory map based on the precise coordinates of all vehicles in the warehouse (e.g., vehicle LSVAF2A45LNXXXXXX coordinates X51.25, Y39.19) and their real-time status (in stock / being moved) fed back by a multi-point RFID positioning network. The map is drawn at a 1:100 scale and uses different colors to mark vehicle status (green for in stock, yellow for being moved). Clicking on a vehicle marker displays detailed information (identification number, price, vehicle condition). Buyers can query their target vehicle model (Volkswagen Lavida) through the terminal. The system retrieves three matching vehicles from the database and, combined with the buyer's current location (entrance reception area X10, Y20), uses Dijkstra's algorithm to calculate the optimal viewing route: entrance → A-zone passage → target vehicle location (X51.25, Y39.19). The route is marked on the map with a red line and includes the distance (45 meters) and estimated travel time (2 minutes). It generates inventory statistics reports (185 vehicles in stock, 2 unsold vehicles) and parking space utilization analysis (85% utilization in area A, 60% in area B) for managers, and provides scheduling suggestions (moving 5 vehicles from area A to area B), providing data support for management decisions.

[0064] Therefore, the embodiments should be considered as exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of the equivalents of the application are intended to be included within the invention.

[0065] The above description is merely a specific embodiment of the present invention, enabling those skilled in the art to understand or implement the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features of the invention herein.

Claims

1. A used car inbound and outbound management system, characterized in that, Includes the following modules: The vehicle RFID tag module is used to equip each used car with a unique encrypted RFID tag, which stores the vehicle identification number, initial entry time, preset price, and vehicle status information, and supports information exchange and status updates with the reading device. The intelligent electronic price tag module is used to bind an intelligent electronic price tag to each used car, receive and display basic vehicle information, real-time price and status, and has a built-in RFID reading unit that periodically scans surrounding tags to verify the consistency of identity and location and generate verification results. The warehouse management module is used to collect tag information through the RFID reader at the entrance when vehicles enter the warehouse, complete vehicle information registration, vehicle condition verification, and price suggestion generation, and synchronize the warehouse data and price suggestions to the smart electronic price tag module. The outbound management module is used to verify the tag information through the access control RFID reader when a vehicle leaves the site, and update the vehicle status to be sold or left. If a temporary relocation is required, the relocation time, target area and operator are recorded and synchronized to the smart electronic price tag module. The inventory monitoring and alarm module is used to receive the verification results of smart electronic price tags and vehicle inventory data from the database, to calculate the inventory quantity in real time, calculate the duration of slow sales, trigger alarms for inventory exceeding limits or slow sales exceeding time, and to locate abnormal vehicles by combining location information. The multi-point RFID positioning network module is used to deploy dense RFID reader nodes in the market, collect the tag signal strength received by each node, calculate the precise coordinates of the vehicle through the triangulation algorithm, and output positioning data. The inventory map visualization module receives location data and vehicle status information, generates a real-time inventory distribution map, supports buyer queries and optimal vehicle viewing route planning, and provides managers with a basis for scheduling and site planning decisions.

2. The used car entry and exit management system according to claim 1, characterized in that, The vehicle RFID tag module includes the following functions: Each used car is assigned a unique identification tag, and basic information such as vehicle identification number, year of manufacture, model configuration, and initial vehicle condition level is entered into the tag; The entered basic information is encrypted using a symmetric encryption algorithm, and the encrypted core data block is stored in the secure storage area of ​​the RFID tag. When a vehicle enters the site, it establishes a communication connection with the RFID reader at the entrance, receives the entry timestamp sent by the reader, and updates the entry status in the tag to pending confirmation. When a vehicle leaves or is moved, it interacts with the access control or area reader to receive a status update instruction and changes the vehicle status in the tag to sold, departed, or being moved. It regularly responds to scanning requests from the built-in reading unit of the smart electronic price tag, outputs encrypted identity information for verification, and ensures that the binding relationship between the tag and the vehicle is not tampered with.

3. The used car entry and exit management system according to claim 1, characterized in that, The intelligent electronic price tag module includes the following functions: Receive vehicle basic information, price suggestions and inventory status synchronized from the inventory management module, convert the data into a standardized display format, and display the vehicle identification number, price, vehicle condition level and inventory status in the price tag screen in sections; The built-in RFID reading unit is activated according to the preset scanning cycle, and a fixed frequency radio frequency detection signal is emitted to the surrounding area; The system receives encrypted response signals from RFID tags on vehicles within its range, amplifies and filters the signals, and extracts encrypted identity information. The decryption algorithm is called to decrypt the encrypted identity information to obtain the target vehicle identification number. The target vehicle identification number is then compared field by field with the vehicle identification number bound to the target vehicle to generate an identity and location consistency verification result. It establishes a long-term connection with the market management database in real time, receives update instructions such as price adjustments and status changes issued by the database, refreshes the price tag display content synchronously, and uploads the verification results and update status to the inventory monitoring and alarm module.

4. The used car entry and exit management system according to claim 3, characterized in that, The step of activating the built-in RFID reading unit according to a preset scanning cycle includes: The system reads the preset scanning cycle parameters from the smart electronic price tag, which are dynamically adjusted by the system based on the market vehicle density. When the scanning time point is reached, the transmitting circuit of the built-in RFID reading unit is activated, generating a radio frequency detection signal that conforms to the ISO standard and transmitting it to a preset radius range centered on the price tag; The system receives response signals from RFID tags of vehicles within its range, performs noise reduction and shaping on the signals, and removes noise caused by environmental interference and signal attenuation. The processed valid signal is converted into a digital signal stream, and the encrypted identity information field and signal strength value are parsed out according to the communication protocol of the RFID tag; The encrypted identity information is parsed and its integrity is verified. The data length and check bits are checked to see if they meet the preset specifications, and valid identity information is filtered out. The system compares the valid identity information with the vehicle identification number bound to it. If they match, a verification result is generated. If they do not match or no matching tag is detected, an error message is generated and synchronized to the inventory monitoring and alarm module.

5. The used car entry and exit management system according to claim 4, characterized in that, The integrity verification of the parsed encrypted identity information includes: Extract the data length field from the parsed encrypted identity information and compare it with the system's preset standard data length; If the data lengths are consistent, extract the cyclic redundancy check code at the end of the information and perform cyclic redundancy check calculation on the entire encrypted data block. The calculated check code is compared with the extracted check code to determine whether there is any loss or tampering during data transmission. If the verification code matches, further verify the format identifier bit of the encrypted data block to confirm that the data conforms to the tag's storage format specification; Generate integrity verification results. If all verification items pass, the data is marked as valid identity information; otherwise, it is marked as invalid data and discarded. Valid identity information is transmitted to the next comparison process, while the reception time and signal strength information of invalid data are recorded for subsequent positioning network optimization.

6. The used car entry and exit management system according to claim 1, characterized in that, The warehouse management module includes the following functions: When a vehicle enters the market entrance, it triggers the RFID reader at the entrance to read the encrypted basic information in the vehicle's RFID tag. The encrypted basic information is decrypted, the vehicle identification number is extracted, and compared with the vehicle information already registered in the market database to determine whether it is the first time it has entered the database. If it is the first time the vehicle is put into the warehouse, the vehicle condition verification process will be initiated. High-definition cameras will be used to collect images of the vehicle's exterior, sensors will be used to detect the status of key components, and a vehicle condition level assessment result will be generated. Call the price generation model, input the vehicle brand, model, vehicle condition level, years of use, and market supply and demand parameters, and generate an initial price suggestion; Enter the vehicle identification number, entry time, vehicle condition level, and suggested price information into the market database to create a vehicle entry file; The core display information in the inbound file is synchronized to the corresponding smart electronic price tag module, triggering a price tag display update, and the vehicle status is set to in stock.

7. The used car entry and exit management system according to claim 1, characterized in that, The inventory monitoring and alarm module includes the following functions: The system reads the entry time, current status, and price information of all vehicles in the market database in real time to create a dynamic inventory list. Receive the identity and location consistency verification results uploaded by the smart electronic price tag module, and mark the vehicles marked as abnormal separately; The total number of vehicles in the dynamic inventory list that are in stock is counted and compared with the system's preset inventory upper limit threshold. Calculate the unsold duration of each vehicle in the warehouse, which is the difference between the current time and the time of entry into the warehouse, and compare it with the preset unsold duration threshold. If the total inventory exceeds the upper limit threshold, an inventory over-limit alarm message will be generated, including the current inventory quantity, the over-limit difference, and the suggested scheduling direction; If there are vehicles whose unsold period exceeds the threshold, an unsold period alarm message will be generated, which includes the vehicle identification number, unsold period, and current price. It receives positioning data from a multi-point RFID positioning network module, associates the location information of abnormal vehicles, over-limit inventory vehicles, and slow-selling vehicles with alarm information, and generates a comprehensive alarm notification to send to the management terminal.

8. The used car entry and exit management system according to claim 1, characterized in that, The multi-point RFID positioning network module includes the following functions: High-density RFID reader nodes are deployed at key locations such as intersections, parking areas, and entrances / exits within the market. Each node has a built-in location coordinate chip. Each reader node is continuously in signal receiving mode, collecting radio frequency signals emitted by RFID tags of surrounding vehicles in real time, and recording the signal reception time and signal strength value; Each node packages the collected signal strength value, its own location coordinates, and the signal reception timestamp into a positioning data frame, and uploads it to the positioning computing unit through the wireless communication network. The positioning calculation unit receives positioning data frames from multiple nodes for the same vehicle within the same time period and filters out valid data frames with signal strength greater than a threshold. The signal strength values ​​in the valid data frames are normalized to eliminate errors caused by hardware differences between different nodes; The triangulation algorithm is used to construct a positioning triangle with the coordinates of each node as the vertices and the distance corresponding to the normalized signal strength as the side length. The centroid coordinates of the positioning triangle are calculated and corrected using a signal strength weighting factor to obtain the precise position coordinates of the vehicle. The precise location coordinates are checked for boundaries to ensure that they fall within the pre-defined geographical area of ​​the market, generating valid location data and feeding it back to the inventory monitoring and alarm module and the inventory map visualization module.

9. The used car entry and exit management system according to claim 8, characterized in that, The process of calculating the precise vehicle position coordinates using the triangulation algorithm includes: Extract the position coordinates of at least three different nodes and their corresponding normalized signal strength values ​​from the valid data frame; Based on the radio frequency signal propagation attenuation model, the normalized signal strength value of each node is converted into the straight-line distance from the vehicle to that node; Establish a two-dimensional rectangular coordinate system with the position coordinates of the first node as the origin, and convert the position coordinates of other nodes into coordinate values ​​in this coordinate system; Based on the coordinates and corresponding distances of the three nodes, three sets of distance equations are listed to form a system of equations; The system of equations is solved using the least squares method to obtain the initial coordinates of the vehicle in this coordinate system. The initial coordinate values ​​are converted into market-standard geographic coordinates to obtain preliminary positioning coordinates; Extract the vehicle's historical positioning data, calculate the deviation between the preliminary positioning coordinates and the historical coordinates, and perform smoothing if the deviation exceeds a preset threshold. By combining the signal strength weights of each node, the initial positioning coordinates are weighted and corrected to generate the final accurate position coordinates; The precise location coordinates are associated with the node number and the calculation timestamp to form a complete location data record.

10. A method for managing the entry and exit of used cars, characterized in that, The method is implemented based on the used car entry and exit management system described in any one of claims 1-9 above, and the used car entry and exit management method includes the following steps: Step S01: Install a unique encrypted RFID tag on each used car, enter the basic vehicle information and store it encrypted, and complete the binding of the tag to the vehicle; Step S02: Bind the smart electronic price tag to the vehicle, establish a communication connection between the price tag, RFID tag, and market database, and complete the initial information synchronization and display; Step S03: When a vehicle enters the parking lot, the RFID reader at the entrance collects the tag information, completes the vehicle condition verification and price suggestion generation, registers the vehicle in the storage file and updates the price tag display; Step S04: The smart electronic price tag periodically scans the tags to generate verification results, the positioning network calculates the precise location of the vehicle, and the monitoring module counts inventory and unsold goods and triggers an alarm. Step S05: When a vehicle leaves the premises, the tag information is verified by the access control reader, and the status is updated to "sold" or "departed"; when a temporary transfer occurs, the transfer information is recorded and synchronized to the price tag and the database; Step S06: Generate an inventory map based on location data and vehicle status, supporting querying and route planning, and providing data support for management decisions.

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