Closed environment interference sensing adaptive frequency modulation RFID read-write control method and system

Abstract

This invention relates to the field of radio frequency identification (RFID) technology, specifically to a closed-environment interference-sensing adaptive frequency modulation RFID read / write control method and system. It aims to solve the problems of RFID signals being susceptible to multi-source interference in closed environments, and the insufficient reliability and efficiency of layered area tag reading and inventory. This invention uses door opening / closing events or inventory commands to drive multi-dimensional interference sampling, constructing a three-dimensional channel quality map of frequency point, antenna, and time. With the goal of maximizing accumulated effective channel quality and minimizing switching overhead, it jointly optimizes and generates frequency hopping sequences, dwell strategies, and antenna polling sequences, dynamically adapting RF transmission parameters. Simultaneously, it achieves carrier frequency offset closed-loop compensation and online update of the interference model. Using identity authentication as a pre-inventory trigger condition, it constructs an anomaly response and security traceability closed loop, realizing highly reliable and efficient RFID tag inventory and full-process security control within closed cabinets.

Description

Technical Field

[0001] This invention relates to the field of radio frequency identification (RFID) technology, and more specifically, to a closed-environment interference-sensing adaptive frequency modulation RFID read / write control method and system. Background Technology

[0002] Radio Frequency Identification (RFID) technology, with its core advantages such as non-contact batch identification, long-distance reading and writing, and no need for visual contact, has become a core technology for achieving refined management of items in fields such as intelligent file management, asset control, and warehousing and logistics. Closed intelligent RFID cabinets are also a key carrier for closed-loop management of confidential files, valuable media, and important assets.

[0003] Current RFID reading and writing solutions for enclosed cabinet scenarios mostly employ a frequency hopping mode with a preset fixed sequence. This lacks real-time linkage optimization between interference sensing results and frequency modulation strategies, failing to balance channel communication quality with frequency and the performance overhead of antenna switching. Furthermore, conventional solutions generally use fixed operating frequencies, fixed transmit power, and fixed-sequence antenna polling, making them ill-suited for dynamic multi-source interference caused by multipath effects, environmental noise, co-frequency signal occupancy, and multi-antenna coupling in enclosed metal environments. This easily leads to problems such as tag reading blind spots, high communication error rates, and unstable inventory success rates. In addition, existing solutions lack real-time compensation mechanisms for frequency drift caused by carrier frequency offset and device temperature drift, resulting in insufficient dynamic anti-interference capabilities. They also often separate identity authentication from inventory execution processes, failing to form a complete technical closed loop encompassing access control, inventory execution, anomaly response, and security traceability, posing potential security risks.

[0004] To address the numerous shortcomings of the existing technologies, this invention proposes a closed-environment interference sensing adaptive frequency modulation RFID read / write control method and system. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a closed-environment interference-sensing adaptive frequency modulation RFID read / write control method and system.

[0006] To achieve the above objectives, the present invention provides the following technical solution: An adaptive frequency modulation RFID read / write control method for interference sensing in enclosed environments includes the following steps: Step 1: Define the data flow: Define the key data flows, including perceived data, model data, configuration data, feedback data, and learning data; Step 2, Multi-dimensional Interference Perception and Channel Quality Map Generation: Based on the cabinet door opening / closing status switching event or inventory trigger command, parallel sampling of environmental noise, co-frequency signal occupancy, and multi-antenna coupling interference in the closed environment is initiated. After normalizing and fusing the multi-dimensional sampling data, a three-dimensional channel quality map covering frequency point, antenna, and time dimensions is generated. Step 3: Fine-grained frequency modulation and frequency hopping sequence generation: Based on the channel quality map, fine-grained tuning of the local oscillator frequency is completed. With the optimization objectives of maximizing the accumulated effective channel quality and minimizing the handover performance overhead within a preset time window, the frequency hopping sequence, dwell strategy and antenna polling order are jointly optimized and generated. Step 4: Dynamically configure transmission parameters and implement adaptive day-to-day scheduling: Dynamically adapt radio frequency transmission parameters based on the channel quality map, and implement adaptive day-to-day scheduling in combination with the tag distribution density of the corresponding area of ​​each antenna. Step 5: Closed-loop compensation for carrier frequency offset and frequency drift: Based on the pilot signal inserted during communication, phase information is extracted, frequency error is estimated, and real-time compensation for carrier frequency offset and frequency drift is completed through closed-loop adjustment. Step 6: Online update and pre-tuning of the interference model based on historical logs: Update the interference model online based on historical inventory logs, and perform pre-tuning of communication parameters based on the model prediction results; Step 7: Closed-loop technical control based on authentication triggering and abnormal response: The successful authentication signal is used as the prerequisite for starting the inventory process, and the abnormal inventory status triggers the review execution and full-process security traceability control.

[0007] The present invention also provides a closed environment interference sensing adaptive frequency modulation RFID read and write control system, including a read and write control unit, a radio frequency transceiver front-end unit, a multi-antenna switching unit, a baseband processing unit, a storage unit and an identity authentication unit; The read / write control unit is used to respond to trigger events, schedule interference perception processes, construct channel quality maps, generate frequency modulation and antenna scheduling decisions, execute closed-loop compensation control, and update interference models. It also manages the entire process of identity authentication, inventory execution, anomaly response, and security traceability, and coordinates with other units to operate in a coordinated manner. The radio frequency transceiver front-end unit is used to perform full-band spectrum scanning, environmental noise and co-channel interference sampling, realize fine-grained local oscillator frequency tuning and dynamic adaptation of transmit power, complete up-conversion and down-conversion processing of radio frequency signals, and provide radio frequency link support for interference sensing and tag communication. The multi-antenna switching unit is used to cooperate in completing multi-antenna coupling interference sampling, executing antenna polling commands, realizing on-demand selection and switching control of read and write antennas, and adapting to the tag reading and inventory requirements of the cabinet's layered areas; The baseband processing unit is used to complete signal modulation and demodulation, pilot sequence extraction, carrier frequency offset and frequency drift estimation, and tag communication protocol parsing, providing baseband processing capabilities for frequency offset closed-loop compensation and reliable tag data reading. The storage unit is used to store sensing data, channel quality models, configuration parameters, historical inventory logs, and tamper-proof operation traceability records, providing data support for model self-learning, access control, and event traceability. The identity authentication unit is used to integrate multi-mode identity authentication capabilities, output a successful authentication signal as a prerequisite for starting the inventory process, and cooperate to complete high-level permission verification in emergency unlocking scenarios.

[0008] Furthermore, in the multi-dimensional interference perception and channel quality map generation step, when multi-dimensional interference sampling is initiated, the current conventional communication mode is interrupted to enter the perception configuration stage. Full-band spectrum scanning is performed to acquire environmental noise and co-channel occupancy data. Low-power detection signals are used to poll and activate antennas to acquire multi-antenna coupling interference data. The full-band spectrum scanning uses a fixed step size within a preset working frequency band, stopping at each frequency point for a preset scanning time to record the noise floor. Simultaneously, a carrier sensing mechanism is used to detect co-channel occupancy signals. The transmission power of the low-power detection signal is lower than the transmission power of normal tag reading and writing to avoid false triggering of tags inside the cabinet.

[0009] Furthermore, the channel quality map is a three-dimensional structured matrix. Each element in the matrix is ​​obtained by weighted comprehensive calculation based on three factors: noise floor level, co-channel occupancy status, and antenna coupling interference degree. The lower the noise floor level, the less co-channel occupancy, and the less antenna coupling interference, the higher the corresponding channel quality value.

[0010] Furthermore, in the fine-grained frequency modulation and frequency hopping sequence generation step, a high-precision digital frequency synthesizer is used to achieve fine-grained frequency tuning with a step size smaller than the spectrum scanning step. The frequency control word is calculated and determined based on the ratio between the optimal frequency point and the reference clock frequency, and the bit width of the phase accumulator determines the resolution of the frequency tuning.

[0011] Furthermore, the joint optimization of the frequency hopping sequence, dwell strategy, and antenna polling order is solved using a greedy algorithm, specifically including: initializing the remaining duration of the time window, the current frequency, and the antenna; traversing all available frequency-antenna combinations to calculate the immediate benefit, which comprehensively considers the current channel quality, frequency switching overhead, and antenna switching overhead; selecting the frequency-antenna combination with the largest immediate benefit as the next working channel configuration; updating the remaining duration, the current frequency, and the antenna; repeating the above steps until the remaining duration is less than the minimum dwell time.

[0012] Furthermore, in the step of dynamically configuring transmission parameters, the transmission power and the channel quality map are linked in real time for dynamic adaptive adjustment. The transmission power adjustment amount is calculated based on the relative relationship between the current channel quality value and the preset quality threshold. When the channel quality is high, the transmission power is appropriately reduced, and when the channel quality is low, the transmission power is increased. The adaptive antenna-based scheduling determines the antenna polling order based on the tag distribution density in the hierarchical area responsible for each antenna using a probability sampling method. The probability of an antenna being selected is proportional to the number of tags in its corresponding area. The denser the tags in an area, the higher the antenna scheduling priority.

[0013] Furthermore, in the closed-loop compensation step for carrier frequency offset and frequency drift, a fixed-length single-frequency pilot symbol is inserted into the interrogation command of each communication. The frequency error estimate is obtained by fitting the slope of the phase change of the received pilot signal over time through linear regression. The frequency error estimate is a specific proportional relationship of the slope of the phase-time curve fitting. The closed-loop compensation uses a proportional-integral regulator to generate the frequency correction amount. The proportional term is determined based on the current frequency error value, and the integral term is determined based on the historical cumulative frequency error value. The two are weighted and combined to generate the final frequency correction command.

[0014] Furthermore, in the online update step of the interference model based on historical logs, the interference model includes an environmental state classification model and an interference time series prediction model. The environmental state classification model is trained based on the environmental features corresponding to the historical optimal configuration, and outputs the interference type classification result and the optimal weight parameter set. The interference time series prediction model is trained based on the time series of historical environmental interference statistics, and outputs the predicted value of future interference and the optimal channel configuration recommendation. The training samples of the environmental state classification model are the environmental features and parameter set corresponding to the log entries with the highest inventory success rate in the historical logs, and the environmental state identification and parameter recommendation are realized through probabilistic classification criteria. The interference time series prediction model adopts an autoregressive moving average model structure, and the model complexity is optimized and determined through information criteria.

[0015] Furthermore, in the closed-loop control steps based on authentication triggering and abnormal response, the output signal of the identity authentication unit is the trigger enable signal for the inventory process. The entire process of interference detection and tag inventory is only authorized when a successful identity authentication trigger signal is received. When the tag reading success rate is detected to be lower than the preset threshold or the tag reading error rate continues to exceed the threshold, the technical instruction for opening the cabinet for verification is automatically triggered and an anti-tampering operation log is generated.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention effectively solves the core problem of existing technologies' inability to adapt to dynamic multi-source interference in enclosed environments by combining event-driven multi-dimensional interference parallel sampling and three-dimensional channel quality map construction technology with fine-grained frequency tuning and frequency hopping sequence joint optimization methods. Driven by door opening / closing events or inventory commands, this invention synchronously collects environmental noise, co-channel occupancy, and multi-antenna coupling interference data within the enclosed environment, quantifying the complex electromagnetic environment into a standardized frequency-antenna-time three-dimensional channel quality map. Based on this, high-precision fine-grained frequency tuning is achieved. With the goal of maximizing accumulated effective channel quality and minimizing handover overhead, frequency hopping sequences and dwell strategies are jointly optimized to accurately avoid various types of interference, balancing communication quality and handover overhead, significantly improving the anti-interference capability of RFID reading and writing, and ensuring the stability and reliability of tag inventory in layered areas within the cabinet. 2. This invention, through dynamic transmission parameter adaptation technology linked to the channel quality map in real time, and an adaptive antenna polling method based on tag distribution density, combined with the technical foundation of prior interference sensing and frequency modulation optimization, further addresses the shortcomings of existing technologies and optimizes system read / write performance. This invention replaces the traditional fixed transmit power, fixed-order antenna polling mode, dynamically adjusting the transmit power according to real-time channel conditions and dynamically planning antenna polling priorities according to tag distribution density, effectively reducing tag reading blind spots and communication errors, and improving inventory efficiency. Simultaneously, it achieves a closed-loop linkage of interference sensing, frequency modulation optimization, and parameter scheduling throughout the entire process, allowing the system to adapt to dynamic changes in a closed environment, further enhancing environmental adaptability and read / write stability. Attached Figure Description

[0017] Figure 1 A flowchart of an adaptive frequency modulation RFID read / write control method for interference sensing in a closed environment; Figure 2 This is a structural reference diagram of the intelligent RFID cabinet in this invention; Figure 3 The structural block diagram of an adaptive frequency modulation RFID read / write control system for interference sensing in a closed environment. Detailed Implementation

[0018] Example 1, refer to Figure 1 The closed-environment interference sensing adaptive frequency modulation RFID read / write control method of this embodiment is applied to an intelligent RFID cabinet, the structure of which can be referred to Figure 2The RFID cabinet is a closed cabinet structure, equipped with an electrically controllable door, multiple shelves and partitioned storage compartments inside, used to store files, media, assets, and other items affixed with RFID tags. The cabinet integrates RFID read / write control units and multiple read / write antennas, enabling RFID tag reading and inventory management throughout the entire cabinet area. It can also be equipped with components such as identity authentication and electrically controlled door locks to meet the intelligent management needs of files and assets. The method of this invention is applied to the entire process control of RFID tag reading, writing, and inventory management in this RFID cabinet, focusing on solving problems such as poor RFID read / write reliability and low inventory efficiency caused by multi-source interference in a closed cabinet environment. Specifically, it includes the following steps: Step 1: Define the data flow.

[0019] The closed environment interference sensing adaptive frequency modulation RFID read and write control system of the present invention is deployed in the above-mentioned RFID cabinet, including a read and write control unit, a radio frequency transceiver front-end unit, a multi-antenna switching unit, a baseband processing unit, a storage unit and an identity authentication unit; the read and write control unit, as the core processing module, is electrically connected to the above-mentioned units and undertakes the full-process control functions of sensing triggering, modeling calculation, decision generation, execution control and model updating. To achieve closed-loop control, the following key data flows are defined. All data flows adopt a standardized structured format to ensure seamless connection between each stage: Sensing data includes real-time sampled Received Signal Strength Indicator (RSSI), channel noise floor, co-occupancy flags of adjacent readers, and coupling coefficient matrix between multiple antennas, providing raw input for channel quality map modeling; Model data: namely, channel quality map, is a three-dimensional structured data matrix with frequency point dimension, antenna index dimension, and time slice dimension. Each element in the matrix is ​​a weighted channel quality value that integrates noise floor, co-channel interference intensity, and antenna coupling coefficient, used to describe the channel communication quality under different frequency-space-time dimensions. Configuration data includes local oscillator frequency control word, frequency hopping sequence, dwell time slice length, antenna polling sequence table, and transmit power control word, providing execution instructions for the RF front-end transceiver unit and multi-antenna switching unit; Feedback data includes carrier frequency offset estimates, frequency drift rate, tag inventory success rate, tag reading error rate, and average reading time per tag, providing feedback for closed-loop compensation and model updates. Learning data: namely, historical inventory logs, which include the triggering events of each inventory task, the initial channel quality map snapshot, the full configuration parameters of the final execution, the feedback data of the execution process, and the final inventory results, providing a training dataset for online updates of the interference model.

[0020] Step 2: Multi-dimensional interference perception and channel quality map generation.

[0021] To address the complexity and dynamism of interference sources in closed environments, this invention employs an event-driven sensing mechanism. Physical events and command signals are used as unified trigger sources to initiate synchronous parallel sampling of multiple interference types. After normalization, the sampled data is used to construct a standardized channel quality map, providing a unified quantitative basis for all subsequent decision-making processes.

[0022] When the read / write control unit detects a state transition event where the RFID cabinet door changes from closed to open, or receives an inventory trigger command from the upper level, it immediately interrupts the current regular communication mode and enters the sensing and configuration phase, performing full interference sensing and channel quality map construction. The sensing process is divided into the following three parallel sub-processes: S21. Environmental noise and co-frequency occupancy sampling: The read / write control unit controls the radio frequency front-end within a preset operating frequency band, for example... With fixed steps ,For example Perform a full-band spectrum scan; at each frequency point Above, stay for the preset scanning time Record the noise floor at that frequency point. The unit is Simultaneously, a carrier sensing mechanism is used to detect whether other readers or wireless devices are using the same frequency. If a valid occupancy signal is detected, a co-occupancy flag is displayed. Set to 1 otherwise set to 0; Scan time The typical range of values ​​is The values ​​are determined based on the spectral scan response speed of the RF front-end and the required measurement accuracy of the noise floor. The longer the time, the higher the accuracy of the noise floor measurement, but the longer the total time consumed in the sensing phase. It can be adjusted according to the real-time requirements of inventory. S22, Multi-antenna coupling interference sampling: For those with The RFID cabinet reader system with one antenna sequentially activates each antenna to transmit a low-power detection signal, while the remaining antennas receive the same signal, thus creating a [system / system]. Coupling coefficient matrix ; where matrix elements Indicates antenna During transmission, the antenna The strength of the received coupled signal; in particular, when hour, Defined as antenna The self-reflection coefficient, i.e., the standing wave ratio related parameter; The typical transmit power of a low-power detection signal is... The value is lower than the normal transmit power for tag reading and writing, which can ensure the accuracy of coupling coefficient measurement while avoiding false triggering of tags in the cabinet; Based on the coupling coefficient matrix, the coupling interference coefficient between antennas is calculated. It is the normalized coupling strength, calculated using the following formula: ; The denominator is the maximum value of all off-diagonal coupled elements, ensuring... Mapped in Within the range, this coefficient quantifies the degree of interference that may occur between different antennas when they are working simultaneously, providing a basis for spatial interference dimensions for antenna scheduling and channel quality assessment. S23. Channel quality map generation: The aforementioned multi-dimensional sensing data are fused to generate a channel quality map. ; It is a three-dimensional structured matrix, with dimensions representing frequency points. Antenna Index and time slices The time slice is defined by the subsequent frequency hopping dwell strategy, and each element in the matrix... Represents frequency point Using an antenna In the Expected channel quality when communicating in a time slice It can be calculated using the following formula: ; in, For frequency point The current noise floor, This term represents the maximum noise floor across the entire scanning frequency band and is used to normalize the ambient noise level. The quality contribution value between them, the higher the value, the less noise interference; For frequency point The co-channel occupancy flag has a maximum value of 1 when there is no co-channel occupancy, indicating no co-channel interference. Indicates when the antenna During operation, the sum of the coupling interference from other antennas is averaged to obtain the average coupling interference. This item reflects the spatial interference cost that must be paid when the antenna is activated. The lower the value, the less interference between antennas. Let be the weighting coefficient, satisfying The specific value can be configured according to the deployment scenario of the RFID cabinet and the number of antennas. For example, in a cabinet scenario with multiple antennas densely deployed, the value can be appropriately increased. The weights are assigned to prioritize avoiding multi-antenna coupling interference; in a preferred embodiment, ; Time slice The range of basic time units is The length of a single time slice is matched with the minimum time consumption of a single tag read / write operation, and the subsequent frequency hopping dwell strategy can adjust the dwell time of a single channel based on this basic unit. Using the above formula, the channel quality map quantifies the abstract physical electromagnetic environment inside the cabinet. The standardized values ​​between these values ​​indicate that the higher the value, the better the channel resource quality of that frequency-antenna-time combination, providing a unified quantitative decision-making basis for subsequent frequency scheduling, antenna polling, and power configuration.

[0023] Step 3: Generating fine-grained frequency modulation and frequency hopping sequences.

[0024] After obtaining the channel quality map, a method for fine-grained frequency tuning and frequency hopping-camping-antenna linkage optimization is proposed. This method can not only achieve fine-grained frequency tuning with a step smaller than the scanning step through high-precision digital frequency synthesis and accurately avoid narrowband interference, but also transform the generation of frequency hopping sequence, camping strategy and antenna polling into a joint optimization problem under multiple constraints based on the channel quality map, so as to solve the globally optimal communication path, rather than a simple lookup table frequency switching.

[0025] S31, Fine-grained tuning of the local oscillator frequency: First, regarding the antenna currently in use And the next time film The read / write control unit queries the channel quality map. Iterate through all available frequencies and find the optimal frequency with the highest quality under the given antenna within the current time slot. : ; in, It is the set of all available frequency points; Subsequently, the control unit adjusts the frequency accordingly. Generate the local oscillator frequency control word, and change the local oscillator frequency from the current frequency. Precise tuning to This process is not a simple discrete channel switching, but rather a fine-grained tuning achieved through a high-precision digital frequency synthesizer, with tuning steps smaller than the preset spectrum scanning steps. This enables precise targeting and avoidance of interference depressions, ensuring optimal signal-to-noise ratio in the communication link; The minimum step size for fine-grained tuning can be as small as... Much smaller than the spectrum scan step The frequency control word is calculated as follows: ; in, This is the reference clock frequency for the digital frequency synthesizer. This is the bit width of the phase accumulator in the frequency synthesizer. This formula can be used to convert the target frequency into the corresponding frequency control word, thereby achieving precise frequency tuning. S32. Joint optimization of frequency hopping sequence generation and dwell strategy: Simple point-by-point optimal frequency hopping cannot guarantee optimal global communication performance within the time window, and does not consider the performance overhead caused by frequency switching and antenna switching; therefore, this invention proposes to regard the generation of frequency hopping sequence, dwell strategy and antenna polling order as a joint optimization problem with multiple constraints and multiple objectives, and to achieve the coordinated optimization of multi-dimensional parameters through a unified cost function. Optimization objective: Within a given time window This maximizes the effective channel quality accumulated by the system while minimizing the performance overhead caused by frequency switching and antenna switching, ultimately achieving the core objective of maximizing the number of tags read per unit time and improving the inventory efficiency of RFID cabinets. Time window For a sliding time window, the typical range of window length values ​​is... It can be adjusted according to the total duration and real-time requirements of the inventory task, and the window sliding step size is matched with the single dwell time to realize the continuous dynamic update of the frequency hopping strategy during the inventory process. Constraints: 1. Dwell time constraint: The dwell time for a single frequency hop must be greater than the minimum time required for tag identification and communication. And not exceeding the preset maximum stay time. ; 2. Frequency switching constraints: The frequency interval between adjacent frequency hopping points must meet the settling time requirements of the RF front-end matching circuit to avoid performance loss caused by frequent cross-band switching; 3. Antenna switching constraints: Antenna switching requires allowing sufficient settling time for the switching and matching circuits to avoid signal distortion during the switching process; Among them, the minimum time required for label recognition The typical value is The value is based on the shortest interaction time for a single tag read / write command specified in the UHF RFID protocol; the typical settling time of the RF front-end matching circuit is [value missing]. The typical settling time of the antenna switch and matching circuit is [value missing]. The constraints must ensure that the interval between two adjacent handovers is greater than the corresponding settling time to avoid signal distortion during the handover process from affecting communication performance. Let the frequency hopping sequence be The antenna polling sequence is The residence time series is ,in Let be the number of frequency hopping cycles within the time window. Then, the objective function of the joint optimization problem is: ; In the objective function, all three terms are time-equivalent units to ensure the consistency of the physical meaning of addition and subtraction operations. The first term is the equivalent benefit brought by channel quality, and the latter two terms are the time cost brought by handover operations. To determine the channel quality map, in the 1st... The time slot corresponding to the next frequency hopping uses an antenna. and frequency (Corresponding frequency index) The expected channel quality is dimensionless. Standardized value; Indicates the first The dwell time on the secondary frequency hopping channel is measured in time. The longer the dwell time, the more tag reading operations can be completed on that channel, but it also occupies the opportunity to use other better channels. It needs to be dynamically adapted in combination with channel quality. This represents the time cost function for frequency switching, with the dimension of time. Its value is proportional to the absolute value of the frequency difference between the two frequency hopping cycles, representing the time overhead required for RF front-end stabilization during frequency switching. Specifically... ,in The settling time is the time corresponding to a unit frequency difference, typically taken as [value missing]. ; The dimensionless weighting coefficient represents the cost of frequency switching, and its typical value range is... The larger the weight coefficient, the higher the proportion of overhead caused by switching, and the more inclined the optimization process is to reduce the frequency of switching. This represents the antenna switching time cost function, with the dimension of time. If the cost is zero, then the cost is zero; otherwise, it is a fixed positive number representing the settling time overhead of the antenna switch and matching circuit. The dimensionless weighting coefficient represents the antenna switching cost, and its typical value range is... The larger the weighting coefficient, the more likely the optimization process will reduce the number of antenna switching operations. This invention quantifies factors such as readout rate, channel quality, antenna switching loss, and frequency switching loss through a unified objective function. By solving this optimization problem, the optimal antenna polling order, frequency hopping sequence, and dwell time allocation can be determined simultaneously. This optimization problem can be solved in a finite time using dynamic programming, greedy algorithms, or heuristic optimization algorithms. In a simplified but effective embodiment, a greedy algorithm is used for solving the problem, and the specific execution steps are as follows: Step 1: Initialization, set the remaining duration of the time window to... The current frequency is the initial operating frequency. The current antenna is the initial operating antenna. The cumulative profit is 0; Step 2: Iterate through all available frequency-antenna combinations and calculate the immediate benefit of each combination in the current step: ; in, This represents the optimal dwell time for this combination; Step 3: Select the frequency-antenna combination that yields the greatest immediate benefit. This will serve as the channel configuration for the next task. Step 4: Update remaining time ,in Set the frequency and total antenna switching time for this handover; update the current frequency. Current antenna Add the selected configuration to the frequency hopping sequence, antenna polling sequence, and dwell time sequence. Step 5: Determine the remaining time Is it less than If yes, the algorithm ends and the final sequence is output; otherwise, return to step 2 to continue iterating.

[0026] Step 4: Dynamically configure launch parameters and adaptive daily thread scheduling.

[0027] After determining the frequency hopping and dwell strategies, they need to be translated into specific physical layer execution instructions. This invention proposes a dynamic configuration method for transmission parameters linked to the channel quality map, as well as a programmed antenna polling scheduling method that can automatically adjust according to the tag distribution density. This replaces the traditional fixed power configuration and fixed order polling mode, realizing dynamic optimal allocation of resources and adapting to the tag distribution characteristics of different areas in the RFID cabinet.

[0028] S41. Dynamic configuration of transmission parameters: The core transmission parameter of the reader is the transmission power. In this invention, the transmit power and channel quality map are linked in real time for dynamic adaptive adjustment; for the channel to be used, i.e., the frequency point... ,antenna The corresponding channel, if its channel quality A high channel quality indicates sufficient communication link margin, allowing for a reduction in transmit power to decrease device power consumption and minimize interference with other nearby wireless devices; conversely, a low channel quality indicates poor channel performance. If the transmission power is too low, it is necessary to increase the transmission power to compensate for link loss and ensure communication reliability. Transmit power The dynamic calculation formula is: ; in, The preset base transmission power, typically set to [value]. ; Maximum adjustable power range, in units of Typical value That is, the adjustable range of the transmission power is ; The preset quality threshold is typically set to a value of [value to be filled in]. It can be adjusted according to the overall quality of the channel environment inside the cabinet; when the calculated When the legally mandated maximum transmission power is exceeded, the legally mandated limit shall prevail; when the calculated... When the power is lower than the device's minimum transmission power, the minimum transmission power shall prevail; the legal maximum transmission power for China's UHF RFID band is [missing information]. When the calculation result exceeds this limit, take... As the final transmit power; S42, adaptive day-threaded scheduling: In this invention, the antenna polling order no longer adopts a fixed loop pattern, but dynamically calculates the polling weight and selection probability based on the tag distribution density in the hierarchical area responsible for each antenna, so as to achieve adaptive scheduling where more scheduling resources are available as the tags are denser. The system analyzes the historical inventory logs of the RFID cabinet to calculate the average number of tags within the reading area corresponding to each antenna. ; For the corresponding antenna reading area, the nearest In each successful inventory task, the average number of tags successfully read can be used to exclude invalid log data from inventory anomalies, ensuring that the statistical results accurately reflect the tag distribution density of the corresponding area. antenna The probability of being selected in a complete poll. The number of tags in the area it is responsible for is directly proportional to the number of tags in that area. The calculation formula is: ; in, For example, a small positive number. This is used to avoid the situation where the probability of polling is zero when the number of tags is zero, ensuring that all antennas have a basic polling opportunity; In the actual scheduling process, the system randomly selects the next working antenna based on the above probability distribution. Antenna selection based on the probability distribution is implemented using a roulette wheel sampling method, specifically: the selection probabilities of all antennas are sequentially accumulated to generate... The probability interval within the interval; generate a The antenna corresponding to the probability interval into which the random number falls is the next selected working antenna. This programmed scheduling method ensures that the reader allocates more time and resources to areas with dense tags, thereby improving the overall inventory efficiency and reading success rate of the RFID cabinet. When a new antenna is selected, its corresponding operating frequency, dwell time, and transmission power are all determined by the aforementioned joint optimization algorithm and dynamic configuration method, realizing the linkage optimization of antenna scheduling and frequency configuration.

[0029] Step 5: Closed-loop compensation for carrier frequency offset and frequency drift.

[0030] This invention introduces a real-time closed-loop compensation mechanism based on pilot signals. It uses the phase information extracted from the tag return signal to accurately estimate the frequency offset and drift, and provides real-time feedback compensation to ensure that the demodulation performance in dynamic frequency modulation scenarios is always in the optimal state. In each communication's query command, the system inserts a known, fixed pilot sequence; the pilot sequence uses fixed-length single-frequency pilot symbols, with a typical sequence length of [value missing]. The modulation scheme of the pilot symbols is consistent with that of the subsequent service data to ensure the accuracy of phase estimation; The reader receives the response signal from the tag and extracts the received signal corresponding to the pilot sequence from it, analyzing its phase change. Ideally, the baseband signal of the pilot sequence should be a constant frequency, with its phase changing linearly and fixedly over time. However, the actual received pilot signal undergoes down-conversion, and its phase... Additional changes will occur due to frequency offset and frequency drift; By fitting the slope of the phase change over time using linear regression, the frequency error estimate for the current moment can be obtained. The corresponding phase model is: ; in, The initial phase is expressed in radians. Phase jitter caused by noise, measured in radians; frequency error. That is, the slope of the phase-time curve fitting. The unit of measurement is frequency; the linear regression fitting uses the least squares method, and the fitted sample points are the sampling time and phase estimate corresponding to each symbol in the pilot sequence. The number of sample points is consistent with the length of the pilot sequence, and the sampling interval is equal to the symbol period of the pilot symbol. Obtain frequency error estimate Then, it is fed into a proportional-integral (PI) regulator, which generates a corresponding frequency correction amount through PI regulation and feeds it back to the digital frequency synthesizer to adjust the local oscillator frequency in real time, forming a closed-loop tracking system. The discrete-domain expression for the PI controller is: ; in, For the first The frequency error input value for each sample is measured in units of frequency. For the first The frequency correction amount for the next output, with the dimension of frequency; This is a proportionality constant, dimensionless, with a typical range of values. ; Let be the integral coefficient, with dimensions . The typical value range is The parameters can be tuned according to the response speed and stability requirements of the closed-loop system to ensure the speed and steady-state accuracy of frequency offset compensation. This mechanism can dynamically compensate for carrier frequency offset and frequency drift caused by temperature changes, device aging, Doppler effect, and rapid frequency switching, ensuring that the receiver always works at the optimal demodulation point and reducing the communication bit error rate.

[0031] Step 6: Online update and pre-tuning of the interference model based on historical logs.

[0032] This invention designs an online update mechanism for the interference model based on historical inventory logs, enabling the system to remember typical patterns and changes in interference within the cabinet environment. Simultaneously, based on the updated model, a pre-tuning mechanism is proposed to pre-adjust parameters before interference occurs, achieving zero-wait adaptive behavior and further improving the system's response speed and anti-interference performance.

[0033] S61. Storage specifications for historical inventory logs: After each inventory task is completed, the read / write control unit packages all the data from this task into a standardized log entry and stores it in the storage unit, providing complete training data for model updates. A single log entry contains the following core fields: Trigger event field: Records the trigger source for this inventory count, including RFID cabinet door opening / closing status switching events, timed inventory count instructions, and manual trigger inventory count instructions; Environment-aware field: Records the initial channel quality map snapshot for this inventory check. Interference source characteristic data, environmental noise sampling values; Execution parameter field: Records all configuration parameters executed at the end of this inventory count, including local oscillator frequency trajectory, frequency hopping sequence, antenna polling order, dwell time sequence, and transmit power configuration; Results feedback field: Records the execution results of this inventory count, including the inventory count success rate. This includes the number of successfully read tags / the expected total number of tags, the average time to read each tag, the tag reading error rate, abnormal tag records, the environmental noise sampling value when interference occurs, and the current frequency modulation frequency, etc. The system periodically or when the system is idle, starts an offline learning thread. The typical cycle for periodic startup is [value missing]. The system is considered idle for an hour if: the RFID cabinet is in a closed and locked state, there are no inventory tasks being executed, and the duration of no read / write operations exceeds [a certain timeframe]. Once the conditions are met within minutes, the offline learning thread can be started; this thread uses all historical log entries as the training set to train and update the interference model. S62. Online update mechanism for the interference model: The interference model in this invention comprises two core models: an environmental state classification model and an interference time series prediction model. The model form and update method are defined as follows: 1. Environmental State Classification Model: A Naive Bayes classifier is used. The input features of the model are the statistical features of the channel quality map, including the average noise level across the entire frequency band, the proportion of co-occupied frequencies, the average coupling strength between antennas, and the quantiles of the channel quality values. The output of the model is the interference type classification result, and the optimal weight parameter set for the corresponding interference type, including... Recommended values; the model's training labels are the logs with the highest success rates in inventory checks from historical logs. The environmental features and parameter sets corresponding to log entries are used to achieve classification and parameter recommendation through the maximum a posteriori probability criterion. 2. Interference Time Series Prediction Model: The ARIMA time series prediction model is adopted. The input of the model is the statistical values ​​of environmental noise, co-channel interference, and coupling coefficients arranged in time series from the historical inventory log. The sampling interval of the time series matches the execution interval of the inventory task. The output of the model is the future... The model predicts environmental interference for the inventory task and recommends the corresponding optimal channel configuration. Structure, in which This is the autoregressive order, typically taking the value of [value]. , The difference order is typically taken as . , This represents the order of the moving average, typically taking the value of [value]. The model order can be determined using the Bayesian information criterion. Optimization determined; The offline learning loss function uses mean squared error loss, aiming to minimize the mean squared error between the model's predicted optimal parameter set and the historical optimal execution parameter set. Minimizing the loss function completes the fitting and updating of the model parameters. The updated model parameters include the weighting coefficients in the channel quality map calculation formula. In the frequency hopping optimization objective function Threshold parameters in the transmit power configuration will be used for parameter initialization and decision optimization in the next inventory task. Through this online update mechanism, the system can automatically adapt to long-term environmental changes during the use of the RFID cabinet, such as adjustments to the shelf layout inside the cabinet, interference changes caused by the addition of new electronic devices, and performance deviations caused by device aging, and continuously optimize its anti-interference strategy and parameter configuration. S63. Model-based pre-tuning mechanism: When the system predicts, based on the model updated from historical logs, that a specific type of interference will occur during a certain period of time or after a certain opening and closing of the RFID cabinet, it does not need to wait for the interference to occur before performing sensing and adjustment. Instead, it adjusts the frequency, power and other parameters of the reader to the optimal configuration predicted by the model in advance. The pre-tuning mechanism is triggered when the predicted future interference value output by the interference timing prediction model differs from the environmental characteristics corresponding to the currently used channel configuration by more than a preset threshold, and the predicted interference causes the current channel quality to fall below a preset threshold. When the triggering condition is met, the system will pre-calculate the optimal frequency, power, and antenna polling parameters based on the environmental characteristics predicted by the model, and directly load the optimal configuration when the next inventory task is started, without having to re-execute the full perception process.

[0034] Step 7: Closed-loop control based on authentication triggering and anomaly response.

[0035] The identity authentication result is used as a technical prerequisite for starting the core inventory process of the RFID cabinet, and the abnormal status during the inventory process is used as a technical driving signal to trigger subsequent review and execution actions. The read / write control unit is electrically connected to the identity authentication unit (such as a face recognition camera, IC card reader, or keypad) of the RFID cabinet. The output signal of the identity authentication unit is the trigger enable signal for the inventory process. The reader is only woken up from low-power standby mode and authorized to execute the aforementioned interference sensing, channel quality map construction, adaptive frequency modulation, and tag inventory process when the system receives a successful identity authentication trigger signal (such as a successful face matching signal, IC card verification pass signal, or password verification pass signal). If identity authentication fails, the execution permission of the inventory process will be blocked by hardware and cannot be started. Through this design, identity authentication is clearly defined as a technical pre-trigger condition for starting the inventory process. During the inventory process, the read / write control unit collects feedback data in real time. When an abnormal tag reading condition is detected, the corresponding technical execution action is triggered. These abnormal tag reading conditions include: tag reading success rate below a preset threshold, no response from a specific expected tag, and tag reading error rate consistently exceeding a threshold. The typical threshold for tag reading success rate is [value missing]. That is, the success rate of reading single-area tags is lower than The error rate is judged as abnormal at that time; the typical value for the bit error rate threshold is [value missing]. The duration of continuous judgment is If all read and write operations exceed the threshold, it is considered abnormal; When the above abnormal state is detected, the system performs the following technical operations: 1. Record the abnormal status corresponding to the abnormal label, the area where it is located, the abnormal type and the time of occurrence, and generate an abnormal record; 2. Based on the preset strategy, the technical command for opening the cabinet for verification is automatically triggered, and the electric door lock motor of the RFID cabinet is controlled to perform the opening action. At the same time, the location information and abnormal details of the abnormal tag are output on the interactive interface. 3. Write all the data from this operation, including identity authentication information, cabinet opening time, inventory results, and anomaly details, into an anti-tampering operation log to generate an irrefutable traceability record; The tamper-proof operation log adopts a chained storage structure. Each log entry contains the hash check value of the previous log. Log data cannot be modified after it is written, but can only be appended, ensuring the non-repudiation and integrity of operation records. For emergency unlocking scenarios of RFID cabinets, the system mandates higher-level identity authentication verification. The emergency unlocking action will only be executed after a trigger signal for successful high-level authentication is input, and a complete security traceability record will be generated for the entire process. In summary, this invention solves the technical challenges of multi-source interference, poor adaptability, and low efficiency in RFID layered area inventory in closed environments by employing a series of technical means, including multi-dimensional interference perception, channel quality map quantitative modeling, multi-parameter joint optimization decision-making, real-time closed-loop compensation, and online model self-learning. It achieves highly reliable, efficient, and secure RFID read / write control.

[0036] Example 2, refer to Figure 3 The closed environment interference sensing adaptive frequency modulation RFID read and write control system of this embodiment includes a read and write control unit, a radio frequency transceiver front-end unit, a multi-antenna switching unit, a baseband processing unit, a storage unit and an identity authentication unit; The read / write control unit is responsible for event triggering response, interference perception scheduling, channel quality map modeling, frequency modulation and antenna scheduling decision-making, closed-loop compensation control, and online update of interference model. It also manages the entire process of identity authentication, inventory execution, anomaly response and security traceability, and coordinates the operation of various units. The radio frequency transceiver front-end unit performs full-band spectrum scanning, environmental noise and co-channel interference sampling, realizes fine-grained local oscillator frequency tuning and dynamic adaptive configuration of transmit power, completes up-conversion and down-conversion processing of radio frequency signals, and provides radio frequency link support for interference sensing and tag communication. The multi-antenna switching unit works together to complete multi-antenna coupling interference sampling, executes antenna polling commands, and realizes on-demand selection and switching control of read and write antennas, adapting to the tag reading and inventory requirements of the cabinet's layered areas; The baseband processing unit performs signal modulation and demodulation, pilot sequence extraction, carrier frequency offset and frequency drift estimation, and tag communication protocol parsing, providing baseband processing capabilities for frequency offset closed-loop compensation and reliable tag data reading. The storage unit stores sensing data, channel quality models, configuration parameters, historical inventory logs, and tamper-proof operation and security traceability records, providing data support for model self-learning, access control, and event tracing. The identity authentication unit integrates multiple identity authentication capabilities such as face, IC card, and password, and uses the successful authentication signal as a prerequisite for starting the inventory process, in conjunction with the completion of high-level access verification for emergency unlocking.

[0037] Through the detailed description of the above embodiments, the closed-environment interference-sensing adaptive frequency-modulated RFID read / write control method and system of the present invention achieves accurate and standardized characterization of the complex electromagnetic environment of a closed cabinet through event-driven multi-dimensional interference sensing and three-dimensional channel quality map quantitative modeling; it constructs a fully parameter adaptive anti-interference read / write mechanism through fine-grained frequency tuning, frequency hopping-dwelling-antenna polling joint optimization, and dynamic adaptation of transmit power; it achieves continuous optimization of system read / write performance and long-term environmental adaptation through carrier frequency offset closed-loop compensation and online self-learning of the interference model; and it forms a secure closed loop for the entire asset management process through identity authentication pre-triggered, abnormal response linkage, and anti-tampering chain log traceability mechanism. The present invention effectively solves the core problems of poor adaptability to multi-source interference, insufficient read / write reliability, and lack of closed-loop management in closed environments for RFID inventory. It can be widely applied to various closed RFID storage scenarios such as intelligent file management and important asset and media management, and has strong practical value and promotion prospects.

[0038] The above formulas are all dimensionless calculations, and the preset parameters in the formulas should be set by those skilled in the art according to the actual situation.

[0039] The above embodiments can be implemented, in whole or in part, by software, hardware, firmware, or any other combination thereof. When implemented using software, the above embodiments can be implemented, in whole or in part, as a computer program product. The computer program product includes one or more computer instructions or computer programs. When the computer instructions or computer programs are loaded or executed on a computer, all or part of the processes or functions described in the embodiments of this application are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more sets of available media. The available medium can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium. A semiconductor medium can be a solid-state drive.

[0040] It should be understood that in the various embodiments of this application, the order of the above-mentioned processes does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0041] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0042] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0043] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0044] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0045] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A closed-environment interference-sensing adaptive frequency modulation RFID read / write control method, characterized in that, The method flow is as follows: Step 1: Define the data flow: Define the key data flows, including perceived data, model data, configuration data, feedback data, and learning data; Step 2, Multi-dimensional Interference Perception and Channel Quality Map Generation: Based on the cabinet door opening / closing status switching event or inventory trigger command, parallel sampling of environmental noise, co-frequency signal occupancy, and multi-antenna coupling interference in the closed environment is initiated. After normalizing and fusing the multi-dimensional sampling data, a three-dimensional channel quality map covering frequency point, antenna, and time dimensions is generated. Step 3: Fine-grained frequency modulation and frequency hopping sequence generation: Based on the channel quality map, fine-grained tuning of the local oscillator frequency is completed. With the optimization objectives of maximizing the accumulated effective channel quality and minimizing the handover performance overhead within a preset time window, the frequency hopping sequence, dwell strategy and antenna polling order are jointly optimized and generated. Step 4: Dynamically configure transmission parameters and implement adaptive day-to-day scheduling: Dynamically adapt radio frequency transmission parameters based on the channel quality map, and implement adaptive day-to-day scheduling in combination with the tag distribution density of the corresponding area of ​​each antenna. Step 5: Closed-loop compensation for carrier frequency offset and frequency drift: Based on the pilot signal inserted during communication, phase information is extracted, frequency error is estimated, and real-time compensation for carrier frequency offset and frequency drift is completed through closed-loop adjustment. Step 6: Online update and pre-tuning of the interference model based on historical logs: Update the interference model online based on historical inventory logs, and perform pre-tuning of communication parameters based on the model prediction results; Step 7: Closed-loop technical control based on authentication triggering and abnormal response: The successful authentication signal is used as the prerequisite for starting the inventory process, and the abnormal inventory status triggers the review execution and full-process security traceability control.

2. The closed-environment interference sensing adaptive frequency modulation RFID read / write control method according to claim 1, characterized in that, In the multi-dimensional interference perception and channel quality map generation steps, when multi-dimensional interference sampling is initiated, the current conventional communication mode is interrupted to enter the perception configuration stage. Full-band spectrum scanning is performed to obtain environmental noise and co-frequency occupancy data. Low-power detection signals are used to poll and activate antennas to obtain multi-antenna coupling interference data. The full-band spectrum scanning uses a fixed step to scan within a preset working frequency band, and stays at each frequency point for a preset scanning time to record the noise floor. At the same time, a carrier sensing mechanism is used to detect co-frequency occupancy signals. The transmission power of the low-power detection signal is lower than the transmission power of normal tag reading and writing to avoid false triggering of tags in the cabinet.

3. The closed-environment interference sensing adaptive frequency modulation RFID read / write control method according to claim 2, characterized in that, The channel quality map is a three-dimensional structured matrix. Each element in the matrix is ​​obtained by weighted comprehensive calculation based on three factors: noise floor level, co-channel occupancy status, and antenna coupling interference level. The lower the noise floor level, the less co-channel occupancy, and the less antenna coupling interference, the higher the corresponding channel quality value.

4. The closed-environment interference sensing adaptive frequency modulation RFID read / write control method according to claim 1, characterized in that, In the fine-grained frequency modulation and frequency hopping sequence generation step, a high-precision digital frequency synthesizer is used to achieve fine-grained frequency tuning with a step size smaller than the spectrum scanning step. The frequency control word is calculated and determined based on the ratio between the optimal frequency point and the reference clock frequency, and the bit width of the phase accumulator determines the resolution of the frequency tuning.

5. The closed-environment interference sensing adaptive frequency modulation RFID read / write control method according to claim 4, characterized in that, The joint optimization of frequency hopping sequence, dwell strategy, and antenna polling order is solved using a greedy algorithm, specifically including: initializing the remaining duration of the time window, the current frequency, and the antenna; traversing all available frequency-antenna combinations to calculate the immediate benefit, which comprehensively considers the current channel quality, frequency switching overhead, and antenna switching overhead; selecting the frequency-antenna combination with the largest immediate benefit as the next working channel configuration; updating the remaining duration, the current frequency, and the antenna; repeating the above steps until the remaining duration is less than the minimum dwell time.

6. The closed-environment interference sensing adaptive frequency modulation RFID read / write control method according to claim 1, characterized in that, In the step of dynamically configuring transmission parameters, the transmission power and the channel quality map are linked in real time for dynamic adaptive adjustment. The transmission power adjustment is calculated based on the relative relationship between the current channel quality value and the preset quality threshold. When the channel quality is high, the transmission power is appropriately reduced, and when the channel quality is low, the transmission power is increased. The adaptive antenna-based scheduling determines the antenna polling order based on the tag distribution density in the hierarchical area responsible for each antenna using a probability sampling method. The probability of an antenna being selected is proportional to the number of tags in its corresponding area. The denser the tags in an area, the higher the antenna scheduling priority.

7. The closed-environment interference sensing adaptive frequency modulation RFID read / write control method according to claim 1, characterized in that, In the closed-loop compensation step for carrier frequency offset and frequency drift, a fixed-length single-frequency pilot symbol is inserted into the interrogation command of each communication. The frequency error estimate is obtained by fitting the slope of the phase change of the received pilot signal over time through linear regression. The frequency error estimate is a specific proportional relationship of the slope of the phase-time curve fitting. The closed-loop compensation uses a proportional-integral regulator to generate the frequency correction amount. The proportional term is determined based on the current frequency error value, and the integral term is determined based on the historical cumulative frequency error value. The two are weighted and combined to generate the final frequency correction command.

8. The closed-environment interference sensing adaptive frequency modulation RFID read / write control method according to claim 1, characterized in that, In the online update step of the interference model based on historical logs, the interference model includes an environmental state classification model and an interference time series prediction model. The environmental state classification model is trained based on the environmental features corresponding to the historical optimal configuration and outputs the interference type classification result and the optimal weight parameter set. The interference time series prediction model is trained based on the time series of historical environmental interference statistics and outputs the predicted value of future interference and the optimal channel configuration recommendation. The training samples of the environmental state classification model are the environmental features and parameter set corresponding to the log entries with the highest inventory success rate in the historical logs. The environmental state identification and parameter recommendation are realized through probabilistic classification criteria. The interference time series prediction model adopts an autoregressive moving average model structure, and the model complexity is optimized and determined through information criteria.

9. The closed-environment interference sensing adaptive frequency modulation RFID read / write control method according to claim 1, characterized in that, In the closed-loop control steps based on authentication triggering and abnormal response, the output signal of the identity authentication unit is the trigger enable signal for the inventory process. The entire process of interference detection and tag inventory is only authorized when the trigger signal of successful identity authentication is received. When the tag reading success rate is detected to be lower than the preset threshold or the tag reading error rate continues to exceed the threshold, the technical instruction for opening the cabinet for verification is automatically triggered and an anti-tampering operation log is generated.

10. A closed-environment interference-sensing adaptive frequency-modulated RFID read / write control system, used to implement the closed-environment interference-sensing adaptive frequency-modulated RFID read / write control method as described in any one of claims 1-9, characterized in that, The system includes a read / write control unit, a radio frequency transceiver front-end unit, a multi-antenna switching unit, a baseband processing unit, a storage unit, and an authentication unit; The read / write control unit is used to respond to trigger events, schedule interference perception processes, construct channel quality maps, generate frequency modulation and antenna scheduling decisions, execute closed-loop compensation control, and update interference models. It also manages the entire process of identity authentication, inventory execution, anomaly response, and security traceability, and coordinates with other units to operate in a coordinated manner. The radio frequency transceiver front-end unit is used to perform full-band spectrum scanning, environmental noise and co-channel interference sampling, realize fine-grained local oscillator frequency tuning and dynamic adaptation of transmit power, complete up-conversion and down-conversion processing of radio frequency signals, and provide radio frequency link support for interference sensing and tag communication. The multi-antenna switching unit is used to cooperate in completing multi-antenna coupling interference sampling, executing antenna polling commands, realizing on-demand selection and switching control of read and write antennas, and adapting to the tag reading and inventory requirements of the cabinet's layered areas; The baseband processing unit is used to complete signal modulation and demodulation, pilot sequence extraction, carrier frequency offset and frequency drift estimation, and tag communication protocol parsing, providing baseband processing capabilities for frequency offset closed-loop compensation and reliable tag data reading. The storage unit is used to store sensing data, channel quality models, configuration parameters, historical inventory logs, and tamper-proof operation traceability records, providing data support for model self-learning, access control, and event traceability. The identity authentication unit is used to integrate multi-mode identity authentication capabilities, output a successful authentication signal as a prerequisite for starting the inventory process, and cooperate to complete high-level permission verification in emergency unlocking scenarios.

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