Anti-interference RFID-based blood real-time inventory management system

Abstract

The application relates to the technical field of intelligent management, and is a blood real-time inventory management system based on an anti-interference RFID, which comprises the following steps: acquiring dual-polarization multi-frequency reading data, position grid weight data, near-field operation confirmation data and temperature and humidity data of a blood bag label; updating a blood bag space relation graph based on minimum stable reading power and a reference label correction result, determining a local common mode change arrival sequence and a closed event after being wetted; and determining the storage-in, storage-out, in-storage, wet reading abnormality or to-be-verified state of the blood bag according to the priority of direct inventory change evidence, presumed inventory change evidence and wet reading abnormality evidence. The application can reduce the interference of temporary label reading loss caused by the wetting of the surface of the blood bag in a low-temperature and high-humidity environment on inventory determination, and improve the accuracy and traceability of blood inventory identification.

Description

Technical Field

[0001] This invention relates to the field of intelligent management technology, and is a real-time blood inventory management system based on anti-interference RFID. Background Technology

[0002] Blood products are typically stored in cryogenic blood storage cabinets, and their inventory status directly affects blood dispensing efficiency and safety. Existing blood storage cabinets can use UHF RFID technology to read blood bag tags in batches for blood bag identification and inventory statistics. However, blood bags contain high dielectric loss liquids, and multiple blood bags are stacked on top of each other in their compartments. The tag reading characteristics are easily affected by liquid absorption, tag orientation, blood bag contact relationships, and cabinet structure. When the cabinet door is opened or blood bags are taken out or placed in, external humid air enters the cryogenic zone, potentially wetting the surface of the blood bags. This changes the tag impedance and surrounding electromagnetic boundary conditions, leading to increased reading power, reading fluctuations, or even temporary loss of readability.

[0003] Existing technologies typically determine the blood bag's status based on a single read or whether the tag is readable within a fixed timeframe, making it difficult to distinguish between actual removal and loss of readability due to moisture. Furthermore, reads from a single antenna or frequency are easily affected by changes in polarization direction and local propagation environment. While some solutions incorporate load-bearing detection, issues remain regarding the unique correlation between tag identification and quality changes when multiple locations are operated simultaneously, tags are missed, or multiple bags are continuously removed or placed. Summary of the Invention

[0004] It should be noted that the wet state of blood bags described in this solution refers to the physical phenomenon where, when the blood storage cabinet is operating in a low-temperature environment, the opening of the cabinet door introduces high-temperature and high-humidity outside air. When this warm, humid air encounters the surface of the blood bag and the area where the label is attached, which is at a temperature far below its dew point, condensation occurs, forming a liquid water film or tiny water droplets. This water film significantly alters the impedance matching characteristics of the UHF RFID tag antenna, absorbing and reflecting radio frequency energy, thereby causing a decrease in tag reading sensitivity or even complete loss of readability.

[0005] To overcome the problems existing in the prior art, this invention proposes a real-time blood inventory management system based on anti-interference RFID, comprising: The data acquisition module is used to acquire tag reading data, blood bag storage data, location grid quality data, near-field operation confirmation data, and temperature and humidity data. The reference label management module is used to determine valid reference labels; the operated node determination module is used to determine the operated node based on the position grid quality data and near-field operation confirmation data. The baseline and adjacency graph establishment module is used to establish the label reading baseline and the initial adjacency graph of the blood bag; The dynamic adjacency graph update module is used to update the initial adjacency graph based on changes in the radio frequency response of the operated node and tag; The local common-mode change propagation sequence generation module is used to generate a local common-mode change propagation sequence based on the local common-mode power level changes of the tag and the updated adjacency graph. The module for generating closure events after moisture exposure is used to generate closure event records after moisture exposure based on the local common mode change propagation sequence and the closure time of the adjacency relationship. The inventory status confirmation module is used to confirm the blood bag inventory status based on the operated node and the closing event record after moisture exposure.

[0006] Specifically, the tag reading data includes the reading results of each blood bag tag under different reading channels, interrogation frequencies, and transmission power levels; the data acquisition module is used to determine the minimum stable reading power at which the blood bag tag reaches the stable reading rate threshold under each reading channel and interrogation frequency based on the reading success rate at each transmission power level, and to mark the minimum stable reading power that does not reach the stable reading rate threshold as missing.

[0007] Specifically, the reference label management module is used to establish a reference label candidate table and determine three valid reference labels from the reference label candidate table in each scanning window. At least one of the three valid reference labels is a fixed reference label. The fixed reference label is used to perform reference correction on the change of the dual-polarization power level difference of the blood bag label, and the valid reference label is used to perform reference correction on the change of the dual-polarization average power level of the blood bag label.

[0008] Specifically, the module for determining the operated node is used to match the tag encoding and reading time in the near-field operation confirmation data with the changes in the quality of the location grid. When the matching result is unique, the blood bag node corresponding to the matched tag is determined as the operated node. When the matching result is not unique or the near-field operation confirmation data is missing, the operated node is determined based on the consistency of the changes in the quality of the location grid, the changes in the tag set, and the changes in adjacency. When the operated node cannot be uniquely determined, a record to be verified is generated.

[0009] Specifically, the baseline and adjacency graph establishment module is used to establish a tag reading baseline based on the lowest stable reading power of multiple scanning windows when the blood bag storage state is stable, and to establish an initial adjacency graph based on the position grid number and the stacking order of blood bags; the initial adjacency graph includes blood bag nodes corresponding to the blood bags and direct adjacency edges used to represent the contact relationship between adjacent blood bags.

[0010] Specifically, the dynamic adjacency graph update module is used to determine the open or closed adjacency relationship of directly adjacent edges based on the operated node, the change in the dual-polarization power level difference after reference correction, the change order of adjacent labels, and the pre-established adjacency change template, and to record the opening time and closing time of the adjacency relationship.

[0011] Specifically, the local common-mode change propagation sequence generation module is used to determine the local common-mode power level change of each blood bag label within the coagulation risk time interval based on the reference-corrected dual-polarization average power level change. The time when the local common-mode power level change satisfies the conditions of unidirectional change at multiple interrogation frequency points and the persistence condition is determined as the arrival time of the local common-mode change. The module then generates a local common-mode change propagation sequence based on the updated adjacency graph and the arrival time of the local common-mode change of each blood bag label.

[0012] Specifically, the wet-induced closure event generation module is used to determine the earlier arrival time of the local common mode change in the blood bag labels on both sides of the direct adjacent edge that changes from an open adjacency relationship to a closed adjacency relationship as the arrival time of the local common mode change of the direct adjacent edge; when the arrival time of the local common mode change is earlier than the closing time of the adjacency relationship, and the change in local common mode power level remains unchanged after closure and meets the persistence condition, a wet-induced closure event record is generated.

[0013] Specifically, the inventory status confirmation module is used to confirm the outbound or inbound status of the corresponding blood bag when the operated node has evidence of blood bag removal or blood bag replenishment; when there is no evidence of blood bag removal or blood bag replenishment, and the blood bag label has a record of a closing event after getting wet and has not reached a stable reading rate threshold, the module maintains the inbound status of the corresponding blood bag and marks the reading as abnormal; when the evidence is conflicting or the blood bag label cannot be uniquely identified, a record to be verified is generated.

[0014] Specifically, the system also includes an event management module and a baseline version management module. The event management module is used to set a unique event identifier for each retrieval event and associate and record the event start and end times, the operated node, the change in the position grid quality, near-field operation confirmation data, valid reference tags, tag reading baselines, the arrival time of local common mode changes, the closure time of adjacency relationships, and the closure event record after moisture exposure. The baseline version management module is used to bind the retrieval event to the tag reading baseline version that is effective at the start of the retrieval event, and to establish a tag reading baseline version for subsequent retrieval events after the retrieval event ends.

[0015] Compared with the prior art, the technical effects of the present invention are as follows: 1. This invention integrates near-field operation confirmation, position grid load, tag code set and spatial relationship changes, and sets inventory evidence priority to avoid misjudging blood bags actually in stock as out of stock simply because the tags are temporarily unreadable.

[0016] 2. This invention reduces the impact of antenna polarization, equipment drift, and local electromagnetic environment changes on tag status identification through dual polarization, multi-interrogation frequency scanning, minimum stable readout power analysis, and fixed reference and spatial reference correction.

[0017] 3. This invention constructs and dynamically updates a spatial relationship diagram of blood bags, associating coagulation risk, local common mode change sequence, and adjacent closure process. At the same time, it adopts an immutable baseline version, event logging, and a verification mechanism to realize the review and tracking of inventory status changes and abnormal reading processes. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein: Figure 1 This is a schematic diagram of the structure of a real-time blood inventory management system based on anti-interference RFID according to the present invention. Detailed Implementation

[0019] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0020] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0021] Example 1: This embodiment provides a complete operating logic for a real-time blood inventory management system based on anti-interference UHF RFID, which is used to identify the status of blood bags in storage, receiving, issuing, reading anomalies, and pending verification in a low-temperature storage environment, and to reduce the impact of temporary loss of reading of UHF RFID tags caused by moisture on the surface of blood bags on inventory judgment.

[0022] The system hardware includes a cabinet, at least one blood storage drawer, an RFID reader, a first reading antenna, a second reading antenna, a door status sensor, a drawer status sensor, an air temperature sensor, a relative humidity sensor, a support surface temperature sensor, a position grid load-bearing sensor, a near-field operation confirmation antenna, and a controller.

[0023] The blood storage drawer is divided into multiple compartments, each designed to hold at least one bag of blood. Each bag of blood has a flexible, passive UHF RFID tag on its outer surface, with the tag's code uniquely linked to the blood bag's code.

[0024] The blood bag code, label code, blood storage drawer number, location compartment number, and stacking order together constitute the blood bag storage record.

[0025] A position cell load cell sensor is installed below the support surface of each position cell to collect the total mass of the blood bag in the corresponding position cell. In this embodiment, the mass of a single bag of blood and its packaging is 200g to 350g, and the sensor resolution is 10g.

[0026] An air temperature sensor and a relative humidity sensor are located on the air inlet side of the blood storage drawer, while a support surface temperature sensor is located on the blood bag support surface. The sampling period for all three is 1 second. The measurement errors for air temperature and support surface temperature are no greater than 0.5℃, and the relative humidity is no greater than 3%RH.

[0027] At least three fixed reference labels are installed inside the cabinet. The fixed reference labels are the same model as the blood bag labels and are placed in sealed reference boxes that are radio frequency permeable. The reference boxes are preferably made of non-metallic materials with low water absorption and low radio frequency loss, with a thickness of 0.5mm to 2mm. The boxes contain desiccant and there is no air exchange between the inside and the blood bag storage area.

[0028] The reference box is fixed to a non-load-bearing area on the outside of the blood storage drawer, spaced apart from the metal structure to prevent the metal structure from enclosing the near-field area of ​​the tag antenna. The fixed reference tag is used to characterize the read drift caused by temperature changes in the RFID reader, feeder, reading antenna, and cabinet. Its temperature drift equivalence with the blood bag tag needs to be verified through initialization calibration before it can be added to the reference set.

[0029] The initial calibration was performed under conditions of no handling and no condensation: the operating temperature inside the cabinet was slowly varied at a rate not exceeding 0.5℃ / min within the range of 2℃ to 8℃, while the minimum stable reading power of a fixed reference tag and at least 5 stable blood bag tags was simultaneously collected, and 30 scanning windows were continuously recorded. The power variation of the fixed reference tag at each reading channel and interrogation frequency was used as the reference sequence, and the corresponding variation of each blood bag tag was used as the comparison sequence, and the Pearson correlation coefficient was calculated. The fixed reference tag was allowed to enter the reference set only if, at each reading channel and each interrogation frequency, the correlation coefficient between the fixed reference tag and at least 80% of the blood bag tags was not less than 0.85, and the residual standard deviation did not exceed 1.5dB.

[0030] The RFID reader and RFID tag use the UHF RFID standard and communicate via backscatter. The operating frequency is between 920MHz and 925MHz, with 920.625MHz, 922.625MHz, and 924.625MHz specifically selected as interrogation frequencies.

[0031] The reader performs tag interrogation at each interrogation frequency point, from low to high at 12dBm, 15dBm, 18dBm, 21dBm, 24dBm, and 27dBm. Each reading channel, interrogation frequency point, and transmit power level performs 20 interrogations. The time interval for completing all interrogations under two reading channels constitutes a scanning window (4 seconds in this embodiment).

[0032] In this embodiment, the system performs the following initialization operations before being put into use: (1) Baseline data acquisition is performed, specifically: during the baseline acquisition period when the cabinet door is closed, the blood storage drawer is reset and remains stationary, the RFID reader continuously executes 30 scanning windows. Tags In the read channel and inquiry frequency The minimum stable read power of the baseline is: ;in For the baseline scan window set, The unit is dBm.

[0033] The tags participating in the baseline calculation have at least 24 valid minimum stable read power samples at each read channel and each interrogation frequency.

[0034] Label In the read channel Inquiry frequency Transmit power level and scanning window The read success rate is: For example, a stable read rate threshold .

[0035] The minimum stable read power for the tag is: The unit is dBm.

[0036] The success rate of the tag was less than [percentage missing] across all power levels. At this time, it is recorded as an unstable reading state, meaning there is no valid reading at this frequency point. Value, exemplarily, the interval between adjacent transmit power levels .

[0037] Furthermore, configure the effective judgment window: when the label In the scanning window Simultaneously satisfy: (a) Both read channels have valid and ; (b) at least The window is a valid decision window only if the query frequency point meets condition (a); otherwise, the corresponding indicator is marked as missing.

[0038] Each baseline group is assigned a unique and unmodifiable baseline version number. .

[0039] At the start of a retrieval event, the currently effective baseline version number is written to the event log. All power level changes, reference correction results, dynamic adjacency graphs, local common-mode change propagation sequences, and post-moisture closure event records within the same event use the baseline version bound at the start of the event. A new baseline version is generated after the event is closed.

[0040] (2) Establishing an initial adjacency graph: Specifically, the controller establishes an initial adjacency graph based on the position grid number and stacking order. ;in For the set of blood bag nodes, It is a set of directly adjacent edges, where each edge connects two blood bag nodes that are stacked adjacently in the same cell.

[0041] The properties of directly adjacent edges are either closed (the two blood bags are actually in contact) or open with an air gap.

[0042] The air space at the front of the blood storage drawer is set as the entry node, and a fixed logical connection edge is pre-established from the entry node to the frontmost gap of each position cell as the starting path for the propagation of local common mode changes.

[0043] When a node is deleted, a new direct adjacent edge is created between the original upper and lower adjacent nodes, with the initial attribute being open.

[0044] (3) Continue to calibrate the adjacent changes, including: In this embodiment, the calibration uses the same model of blood bags, RFID tags and location grid structure as the actual operation, and establishes calibration groups according to blood bag specifications, liquid volume range, tag attachment area and stacking layer.

[0045] In this embodiment, during calibration, a thin-film pressure sensor is temporarily installed between adjacent test blood bags: a contact pressure of 1 kPa maintained for 12 seconds is marked as an actual closed state; a contact pressure of less than 0.2 kPa maintained for 12 seconds is marked as an actual open state. For each calibration group, the operations of removing the upper blood bag, removing the middle blood bag, removing the lower blood bag, and replenishing the blood bag are performed, repeated at least 10 times for each type, while simultaneously recording changes in quality, the order of label changes, and power changes.

[0046] After calibration, remove the sensor and form an adjacency change template by recording the direction of mass change, the order of label change, and the direction of power level change corresponding to the actual adjacency state change.

[0047] If the label model is changed, the attachment area is altered, the antenna position or polarization direction is changed, the position grid structure is altered, or the blood bag specifications and liquid volume exceed the existing calibration group range, recalibration should be performed.

[0048] (4) Establish a reference label candidate table, wherein the candidate blood bag label should be separated from the open adjacent edge to be detected by at least two closed direct adjacent edges, have an effective minimum stable reading power in 10 consecutive scanning windows, and the quality change of the cell at the location does not exceed the preset quality change threshold.

[0049] In this embodiment, the fixed reference label and the blood bag label that meets the above conditions together constitute the reference label candidate table; Fixed reference labels are used as a global benchmark in dual-polarization power level difference correction and local common-mode correction; candidate blood bag labels are only used as a supplementary reference for local common-mode correction.

[0050] Each scan window consists of three valid reference labels. At least one of them is a fixed reference label; In other embodiments, if there are fewer than three fixed reference labels, candidate blood bag labels that are farther away from the operated location are selected to supplement the number, but the candidate blood bag labels must pass the following validity check: based on the uncorrected original... The current window of this label has not experienced more than the median of the events in the previous 10 windows. The change is such that the cell at the location has no mass change and the distance from the manipulated location on the graph is greater than the distance between the two edges.

[0051] Any reference tag experiences unstable reading, a change in the quality of its location cell, or Changes reached When judging using uncorrected original values, remove the current reference set and fill it in from the candidate table.

[0052] When there are fewer than three fixed reference tags, the dual-polarization difference correction is paused and downgraded to relying solely on mass change and adjacent templates; when there are fewer than three valid reference tags, the automatic judgment of the wetted state relying on reference correction is paused, the insufficient reference state is recorded and maintenance information is output.

[0053] (5) Further calibrate the support surface temperature, including: simultaneously measuring the support surface temperature and the surface temperature of the blood bag label attachment area during initialization. After stable storage for 30 minutes, if the absolute value of the difference between the two is not greater than 1°C for 10 consecutive minutes, the support surface temperature is allowed to characterize the blood bag surface temperature. If it exceeds 1°C, adjust the sensor position or add a temperature sensor closer to the label area.

[0054] Based on the above process, after the system completes initialization, it further enters steady-state operation, performing the following steps: S100: Continuously acquires tag reading data, blood bag storage data, cabinet status data, location compartment load-bearing data, near-field operation confirmation data, and temperature and humidity data.

[0055] Specifically, the RFID reader continuously performs scanning while the cabinet door is closed and the blood storage drawer is reset, and all raw data is recorded using the system's absolute timestamp.

[0056] The controller continuously acquires tag reading data (tag code, scanning window, reading channel, query frequency, transmission power level and reading result), blood bag storage data, cabinet status data (cabinet door opening and closing time, drawer removal time), position cell load-bearing data (position cell number, sampling time and total mass), near-field operation confirmation data (tag code and reading time), and temperature and humidity data (air temperature, relative humidity, blood bag characterization temperature and dew point temperature).

[0057] Meanwhile, the controller continuously caches the air temperature and relative humidity data of the last 60 seconds.

[0058] When the door status sensor detects that the cabinet door is open The controller traces and locks As a reference window before the cabinet door is opened, the air temperature inside the window is calculated. and relative humidity The arithmetic mean.

[0059] Meanwhile, the controller calculates the dew point temperature based on air temperature and relative humidity, using the Magnus empirical formula: ; ; in , , The dew point temperature is (°C).

[0060] When the blood bag temperature is below the dew point temperature, and the current relative humidity is relative to... The condensation risk time interval begins when the relative humidity increases by at least 5 percentage points and remains elevated for 5 seconds; when the relative humidity is... The interval ends when the difference is no more than 2 percentage points and remains so for 30 seconds.

[0061] It should be noted that in this embodiment, a retrieval event begins when the cabinet door is opened or the blood storage drawer is moved out, and ends when the cabinet door is closed and the blood storage drawer is reset.

[0062] Each retrieval event has two synchronized timelines: the first timeline is the raw event timeline continuously recorded from the start of the retrieval event, used to record changes in temperature and humidity and changes in local common-mode power levels; the second timeline is the start of the first complete scan window after the blood storage drawer has been reset and after the mechanical stabilization waiting time has elapsed. The initial stability determination timeline is used to confirm adjacency closure, new support relationships, and ongoing unstable reading states.

[0063] Specifically, after the blood storage drawer is reset, a mechanical stabilization waiting time is set. For example, preferably, the drawer removal and reset operations are repeated at least 10 times while keeping the blood bag in the same storage state. The time required for the minimum stable reading power of all tags to return to the position before reset and to be maintained continuously for three scanning windows is recorded, and the maximum value is taken as the mechanical stabilization waiting time. In this embodiment, it is 12 seconds.

[0064] S200: Determine the node to be operated on based on near-field operation confirmation data, changes in position grid quality, changes in label encoding set, and adjacency change template.

[0065] Position grid The average mass of the 10 seconds preceding the start of the retrieval event is The average mass after resetting and undergoing a mechanical stabilization waiting time for 10 consecutive seconds is Changes in the mass of the position grid: ; Minimum recognition quality per bag .

[0066] when When evidence of weight loss is formed; when Evidence of weight gain is formed at that time.

[0067] Near-field operation confirms antenna reads tag When the corresponding cell forms evidence of weight loss, direct removal evidence is generated; the label is read. Furthermore, when the corresponding cell forms evidence of weight gain, direct supplementary evidence is generated.

[0068] Near-field confirmation and correlation with location grids require time series matching: comparing the reading time with the time window in which the quality changes of each location grid occur.

[0069] The starting point of the time window for the change in the mass of the position grid is defined as the moment when the mass of the position grid first undergoes a sudden change that lasts for more than 1 second and exceeds the sensor noise threshold (3 times the resolution, i.e., 30g in this embodiment) during the retrieval event; the ending point is the moment when the drawer resets.

[0070] Only if the quality of only one cell within 2 seconds before and after the reading time of the tag changes by more than [a certain value] If the net change is consistent with the direction, a unique match is confirmed; otherwise, it is changed to a pending verification status or a combined match event is generated.

[0071] If no direct retrieval evidence is formed, and the location grid forms weight reduction evidence, the readable tag set after the event is reduced by one tag code compared to before the event, and the change of the adjacent node at the original storage location of the tag is consistent with the applicable adjacency change template, then it is determined as a presumed retrieval node.

[0072] If no direct evidence of insertion is formed, and if the position cell forms evidence of weighting, a new label code is added to the readable label set after the event, and the changes of adjacent nodes are consistent with the applicable insertion adjacency change template, then it is determined as a presumed insertion node.

[0073] When multiple bags are operated at the same location grid at one time, the tags being operated are determined by the tag codes and order recorded by the near-field confirmation antenna; if the record is incomplete, only the location grid and quantity are determined, and the relevant tags are registered as pending verification.

[0074] S300: Calculate the change in the dual-polarization power level difference after reference correction, and update the initial adjacency graph according to the change order of the operated node, adjacent labels, and adjacency change template to obtain the dynamic adjacency graph.

[0075] Specifically, labels In the read channel and inquiry frequency The power level change relative to the baseline is as follows: The unit is dB.

[0076] It should be noted that the above steps are only applicable within the valid decision window and Calculate if valid; otherwise mark as missing.

[0077] Label Inquiry frequency The change in the dual-polarization power level difference is as follows: ; It should be noted that the above steps only apply to two channels. Calculate if all are valid; otherwise, mark as missing.

[0078] The change in the dual-polarization power level difference after reference correction is as follows: ; in For the currently valid set of fixed reference labels (at least 3), this correction uses only fixed reference labels.

[0079] The controller scans the last three full windows before the retrieval event begins. The median is used as a reference value before the event.

[0080] When the distance between the node containing the label and the node being operated on in the initial adjacency graph is no greater than two directly adjacent edges, and at least two query frequencies are present... The changes relative to the pre-event reference value have the same sign (positive or negative), and the absolute value of each change is not less than [amount missing]. (Zero values ​​are not included in the determination), and when three complete scan windows are maintained continuously, it is determined that the tag has undergone an effective dual-polarization power level difference change.

[0081] Once the node to be operated on is determined, the controller deletes the extracted node and its directly adjacent edges, or adds a replacement node.

[0082] After a node is deleted, a new direct adjacency edge is automatically created between the original adjacent nodes (in order of position grid) and the nodes above and below it, with the initial attribute being open.

[0083] When a tag directly adjacent to the operated node undergoes an effective dual-polarization power level difference change according to the applicable adjacency change template, the blood bag gap formed by the node removal or movement is registered as an open adjacency relationship.

[0084] After the blood bag movement is completed, the order of changes in adjacent tags is consistent with the closing phase in the applicable adjacency change template, and the adjacent tags are in the same order under the two reading channels and all participating judgment query frequencies. When three consecutive complete scan windows are at the same level, a closed adjacency relationship is established.

[0085] Directly adjacent edges that change from closed to open The start time of the first valid change in the scanning window that produces the corresponding gap is recorded as the adjacency relationship activation time. ; Directly adjacent edges that change from open to closed The first start time of three consecutive scan windows that satisfy the closure condition is recorded as the adjacency closure time. .

[0086] The controller generates a dynamic adjacency graph based on the above results. .

[0087] S400: Calculate the local common-mode power level change within the condensation risk time interval, and generate a local common-mode change propagation sequence based on the time sequence of effective local common-mode power level changes of adjacent tags.

[0088] Specifically, labels Inquiry frequency The change in average power level under dual polarization is as follows: ; It should be noted that the above steps only apply to two channels. Calculation is performed when all are valid.

[0089] The local common-mode power level changes as follows ,in This is the current set of valid reference labels (including fixed reference labels and candidate blood bag labels that have undergone validity checks).

[0090] The local common mode change vector at multiple query frequencies is: ; The controller scans the last three full windows before the retrieval event begins. The median is used as a reference value before the event.

[0091] Within the time interval of condensation risk, at least two inquiry frequency points The changes relative to the pre-event reference value have the same sign (positive or negative), and the absolute value of each change is not less than [amount missing]. (Zero values ​​are not included in the judgment), and the label is determined when three consecutive scanning windows are maintained. An effective local common-mode power level change occurs.

[0092] The controller starts from the active logically connected edge of the entry node and checks the label layer by layer according to the open adjacency relationship in the dynamic adjacency graph.

[0093] When the tag directly adjacent to the entry node first experiences an effective local common-mode power level change, and the tag connected via an open direct adjacency edge subsequently experiences a change in the same direction, the start time of the first scan window when the corresponding tag first satisfies the continuous holding condition is recorded as the arrival time of the local common-mode change. .

[0094] When multiple position cells have active entry edges at the same time, the propagation sequences of each position cell are processed independently and are not merged.

[0095] For open direct adjacent edges ,node Located on one side of the entrance node and satisfying At that time, by node To node The order of the records indicates the direction of propagation.

[0096] When two nodes undergo valid changes within the same scanning window, they are registered as the same arrival segment.

[0097] Preferably, in another embodiment, a hygroscopic indicator material that changes color upon contact with liquid water is used during the system initialization phase to verify the response sequence.

[0098] Specifically, the center-to-center distance between adjacent labels is 30mm~80mm, the width of the open gap is 2mm~10mm, and a moisture-absorbing indicator strip is set on the surface of the blood bag tested at 2℃~6℃ to simultaneously record the color change time and the scanning window where the RFID response is located.

[0099] Set different positional grid sequences and open gap structures, and repeat at least 10 times. When the sequence of color changes at least 8 times is consistent with the sequence of local common mode changes, it is included in the scope of application.

[0100] S500: The local common-mode change propagation sequence is temporally correlated with the adjacency relationship closure time to generate a record of the closure event after moisture exposure.

[0101] Specifically, for directly adjacent edges that change from open to closed... The earlier arrival time of the local common mode change in the labels on both sides of the edge is determined as the arrival time of the local common mode change of that edge: The unit is seconds (s).

[0102] when At that time, the side It is registered as a closed edge after getting wet.

[0103] If the arrival time of a local common-mode change is not earlier than the closing time of the adjacency relationship, it is not registered.

[0104] After being exposed to moisture, the labels on both sides of the closed edge have already undergone an effective local common-mode power level change before closing; during the closing process... Three consecutive complete scan windows maintain the same level and are consistent with the closing phase in the adjacent change template; after closing, the local common-mode power level change at at least two interrogation frequencies continues to maintain an absolute value relative to the pre-event reference value of not less than And the direction remains unchanged, and a record of the closing event after getting wet is generated when three consecutive scanning windows are completed.

[0105] Each retrieval event is set with a unique event identifier. .

[0106] The event log includes the absolute start and end times of the event, the original event timeline, the stability determination timeline, the operated node, the position grid quality change, the near-field operation confirmation record, the reference tag set, the baseline version, the condensation risk time interval, the adjacency relationship opening time, the local common mode change arrival time, the adjacency relationship closing time, the reference-corrected dual-polarization power level difference change, and the local common mode change vector of multiple interrogation frequency points.

[0107] Lowest stable read power level stable: each The same transmit power level was maintained for three consecutive complete scan windows.

[0108] Local common mode variation stability: at least two participating query frequencies Maintaining the same orientation within three consecutive scan windows, and the absolute value of the difference between values ​​in adjacent windows is less than... .

[0109] The event process is continuous: related data have the same event identifier and the same baseline version, and no other retrieval event in the same blood storage drawer is inserted between adjacent valid scan windows. The local common mode change arrives, the adjacency relationship closes, and the closure is maintained in sequence.

[0110] S600: Confirm the inventory status of blood bags according to the preset evidence priority.

[0111] Specifically, the tag obtains valid results through three consecutive scanning windows under two reading channels and all participating judgment query frequencies. Furthermore, the absolute value of the difference between the local common-mode power level change at each query frequency point and the pre-event reference value is less than [missing value]. At that time, confirm that the label recovery is complete.

[0112] The tag read success rate across five consecutive full scan windows using both read channels, all interrogation frequencies, and all transmit power levels was less than [percentage missing]. At that time, it was determined that the condition of continuous unstable reading had been reached.

[0113] Specifically, if a tag cannot be read continuously and stably, the tag will not participate in the quantization calculation, and the relevant scanning window will be marked as invalid.

[0114] The preset evidence priority is: directly extracting evidence or directly adding evidence takes precedence over recording the event of closing after being wetted; When changes in location grid quality, changes in label code sets, and new support relationships are consistent, indirect evidence of inventory changes is formed. If there is only a record of a closure event after moisture exposure but no direct or indirect evidence of inventory changes, the shipment is not confirmed.

[0115] When a tag is used to directly retrieve evidence, the tag is confirmed to be out of storage and an out-of-storage record is generated. Even if a record of a closing event after getting wet exists, the direct evidence is not negated due to the wet state. When a tag is used to directly supplement evidence, and the stable reading condition is met for three consecutive scan windows in the target location cell, the tag is confirmed to be in storage. If the stable reading condition is not met but the direct supplement evidence is valid, an in storage record is generated and marked as an abnormal tag reading state.

[0116] When no direct retrieval evidence is formed, the target label reaches the condition of continuous unstable reading, the corresponding position cell forms weight reduction evidence, the target label is missing from the label code set after the event, and the original storage position forms a new support relationship consistent with the applicable retrieval adjacent change template, the warehouse is confirmed to be out of the warehouse.

[0117] When no direct evidence of supplementation is formed, if the corresponding cell forms evidence of weight gain, a new label code is added after the event, and the new label and the adjacent blood bag form a closed adjacency relationship consistent with the supplementation adjacency change template, then the blood bag is confirmed to be put into storage.

[0118] If there is no direct or indirect evidence of inventory changes, and the target tag has a record of a closing event after getting wet and has not yet completed recovery within the stable determination timeline, it remains in stock and is marked as an abnormal state of wet reading.

[0119] Once the labels on both sides of the closed edge and the target label have been fully restored after being exposed to moisture, the status is lifted. If there are conflicts between changes in location grid quality, near-field confirmation records, changes in label code sets, and changes in adjacency relationships, or if a single operation involving multiple bags cannot uniquely determine the label code, the status is registered as pending verification.

[0120] The five complete scan windows following the start of the stability determination timeline constitute the initial inventory determination window (20s in this embodiment), used to generate the initial conclusion.

[0121] Set a recovery tracking window for abnormal reading status due to moisture. The window starts when the initial inventory judgment window ends and continues until the earliest of the following: the tag is fully recovered, direct inventory change evidence is formed, on-site verification is completed, or the longest tracking time of 30 minutes is reached.

[0122] If the longest tracking time has not been reached and there is no evidence of inventory changes, maintain the inventory record and generate a tag maintenance task.

[0123] In particular, in another preferred embodiment, an implementation example of multi-event and baseline management is provided as follows: An independent event queue is established for each blood storage drawer. When different drawers are operated on simultaneously, they are processed separately according to the drawer number. If a retrieval operation occurs again before the previous event in the same drawer has been closed, the subsequent operation is established as a related event.

[0124] For tags with direct evidence of removal or replenishment, inventory will still be updated in real time according to evidence priority; for tags that rely solely on local common-mode change propagation sequences and are simultaneously affected by two events, automatic generation of moisture status conclusions will be suspended, and the tags will be registered as pending verification status.

[0125] After the associated event ends, the stability determination timeline is re-established from the first full scan window after the last reset and the mechanical stabilization waiting time.

[0126] When the label code set, location grid quality, and adjacency relationship correspond, the dynamic adjacency graph is reconstructed and automatic judgment is restored; otherwise, an on-site verification task is generated at the end of the initial inventory judgment window.

[0127] After on-site verification is completed, the verification terminal writes the blood bag code, label code, location grid number, stacking order and verification time. The controller then reconstructs the node set and adjacency graph of the corresponding location grid and re-collects the baseline after the cabinet door is closed, the drawer is reset and the mechanical stabilization waiting time has ended.

[0128] After an event is closed, if the cabinet door is closed, the drawer is reset, the dynamic adjacency graph remains stable for five consecutive scan windows, and there are no subsequent pending or ongoing unclosed events in the event queue of the blood storage drawer to which it belongs, 30 scan windows are continuously collected to generate a new baseline version for a stable label with at least 24 valid samples. .

[0129] Tags that are confirmed to be in the database but have not been read stably are registered as baseline postponed tags and will not participate in the new baseline calculation. Once the reading capability is restored, 30 scan windows will be collected separately to generate a new baseline version or sub-version.

[0130] Closed historical events are always preserved and bound to the original baseline version; new baseline versions only apply to events that occur after the time the new baseline version takes effect.

[0131] Example 2: This embodiment provides a specific set of operational procedures for the system operation logic of Embodiment 1, as shown in the following example: The first, second, and third blood bags are stacked in the same compartment from top to bottom, with each bag containing 250 mL of blood.

[0132] The controller registers the first, second, and third blood bags as upper-level, middle-level, and lower-level nodes, respectively. The average mass of the location grid before the retrieval event begins is 812g.

[0133] The operator retrieved the second blood bag, and near-field operation confirmed that the antenna had read the second blood bag's tag code. After the blood storage drawer reset and underwent a mechanical stabilization period, the average mass of the position cells was 541g, and the mass change of the position cells was as follows: ; Because the absolute value of the quality reduction is greater than Furthermore, near-field operation confirmed that the antenna read the second blood bag tag code, and within 2 seconds before and after this near-field reading moment, only this location grid exceeded [a certain value]. The net quality change forms a unique match, the controller generates direct evidence of the removal of the second blood bag, confirms the release of the second blood bag, and deletes the second blood bag node.

[0134] After deleting the second blood bag node, the controller creates a new direct adjacent edge between the first and third blood bag nodes according to the position grid order. The initial attribute is open, representing the air gap formed between the upper and lower layers after the original middle layer blood bag is removed.

[0135] The RFID reader continues scanning while the cabinet door is open.

[0136] After the cabinet door was opened, the air temperature was 7.0℃, and the relative humidity increased from 65% to 74%. The dew point temperature was calculated to be approximately 2.6℃ according to the Magnus empirical formula described in Example 1, and the blood bag characterization temperature was 2.1℃.

[0137] Because the blood bag's characterization temperature is lower than the dew point temperature, and the relative humidity is relative to... (i.e., relative humidity of 65% before the cabinet door is opened) Increase by 9 percentage points and maintain for 5 seconds, then the controller determines the start of the condensation risk time interval.

[0138] The baseline acquisition showed that the lowest stable reading power of the first reading channel of the first blood bag tag at the three interrogation frequencies was 18dBm, 18dBm and 21dBm respectively, and the lowest stable reading power of the second reading channel was 18dBm, 21dBm and 21dBm respectively.

[0139] After the second blood bag was removed, the minimum stable reading power of the first reading channel became 21dBm, 21dBm and 24dBm respectively, and the minimum stable reading power of the second reading channel became 18dBm, 18dBm and 21dBm respectively.

[0140] All of the above power values ​​are valid minimum stable read power, which meet the conditions that both read channels and all three interrogation frequency points are valid. Therefore, the corresponding scan windows are all marked as valid judgment windows.

[0141] At the three interrogation frequencies, the power level change of the first read channel was 3dB, while the power level change of the second read channel was 0dB, -3dB, and 0dB, respectively.

[0142] It should be noted that the median change in dual-polarization power level difference for the three fixed reference tags (all calibrated by channel drift) at the corresponding interrogation frequency points is 0dB. Therefore, the changes in dual-polarization power level difference after the first blood bag tag reference correction are 3dB, 6dB and 3dB respectively. The fixed reference tag is used for correction here.

[0143] The changes in the first blood bag label are maintained for three complete scan windows. Furthermore, the change order of the first and third blood bag labels is consistent with the adjacent change template corresponding to the removal of the middle blood bag. Therefore, the controller registers the first blood bag node and the third blood bag node as an open adjacent relationship.

[0144] For consistency, in this embodiment, the 24s, 32s, 40s, 68s, and 112s all use the start time of the retrieval event as the zero point of the original event timeline. The connecting edge from the entry node to the front gap of the grid at that position is active because of the existence of the frontmost gap (the open gap between the first blood bag and the third blood bag).

[0145] After correction to the median of the reference label, the local common-mode power level of the third blood bag label at the inlet side reached 3dB, 3dB and 1.5dB at the three interrogation frequencies at the 24th second, and remained continuously for the three scanning windows; the local common-mode power level of the first blood bag label reached 3dB, 4.5dB and 3dB at the three interrogation frequencies at the 32nd second, and remained continuously for the three scanning windows.

[0146] The controller records the 24th second and the 32nd second as the arrival times of the local common mode changes of the third blood bag label and the first blood bag label, respectively.

[0147] The response order of the two labels is consistent with the color change order of the moisture-absorbing indicator strip obtained from the initialization verification of that location, and the signs of the changes in both labels are positive and the absolute values ​​are not less than [amount missing]. (The third frequency point of the third blood bag at 1.5dB is not included in the judgment, but at least two of the three frequency points must be satisfied), so the local common mode change propagation sequence is generated in the order from the third blood bag node to the first blood bag node.

[0148] The first blood bag forms a new closed adjacency relationship with the third blood bag at 40 seconds. The lowest stable read power of the first and third blood bag tags across the two read channels and three interrogation frequencies remains at the same level for three consecutive full scan windows starting from 40 seconds, and the sequence of changes is consistent with the closing phase in the adjacency change template corresponding to the removal of the middle layer blood bag. The controller records 40 seconds as the closing moment of the adjacency relationship of the corresponding directly adjacent edge.

[0149] The local common mode change of the corresponding directly adjacent edge arrives at the 24th second, which is earlier than the closing time of the adjacency relationship at the 40th second, thus satisfying the time sequence condition of the closing edge after being wetted.

[0150] After closure, the local common-mode power level of the first blood bag tag at the three interrogation frequencies changed from 3dB, 4.5dB, and 3dB to 6dB, 6dB, and 4.5dB, and remained continuously for three scanning windows, with the direction of change remaining positive and the absolute value still not less than [value missing]. The local common-mode power level change of the third blood bag tag is synchronously maintained. The controller thus generates a record of the closing event after moisture absorption.

[0151] The inlet-side label was restored at 68 seconds, while the first and third blood bag labels continued to maintain local common-mode power level variations.

[0152] The first blood bag tag subsequently failed to reach a stable read rate threshold for five consecutive full scan windows across two read channels, three interrogation frequencies, and all transmit power levels. During this period, the first blood bag tag failed to meet the valid judgment window conditions. Marked as missing, , , , Equivalent quantification indicators are not included in the calculation, and the label enters the continuous unstable reading judgment process.

[0153] There is no new evidence of weight loss at the location of the first blood bag, the near-field operation confirmation antenna has no record of the first blood bag being removed, and the node changes after the event only correspond to the removal of the second blood bag.

[0154] Therefore, the controller maintains the first blood bag in stock and marks it as a wet read abnormality. The first blood bag tag is restored at 112 seconds (i.e., the effective minimum stable read power is obtained in three consecutive scan windows under both read channels and all interrogation frequencies, and the absolute value of the difference between the local common-mode power level change at each frequency and the pre-event reference value is less than 1 / 3 of the original value). The controller then removes the abnormal reading status due to moisture.

[0155] In another operation, the target blood bag was completely removed from the blood storage drawer.

[0156] Near-field operation confirmed that the antenna read the target tag code. The average mass of the target location grid decreased from 523g to 247g, a change of -276g. Within 2 seconds before and after the near-field readout, only this location grid experienced a mass change exceeding [a certain value]. The net weight change forms a unique match. The controller generates direct retrieval evidence based on the target label code and location grid weight loss evidence, and confirms the release of the target blood bag.

[0157] Even if the target blood bag already has a record of a closure event after getting wet before it is removed, the priority of directly removing the evidence is still higher than reading the abnormal state after getting wet, and the controller no longer maintains the inventory record of the blood bag.

[0158] During another run, the target label failed to be read stably for five consecutive full scan windows, but the quality change of the corresponding grid was less than [a certain value]. Near-field operation confirmed that the antenna did not generate a record of target tag retrieval, and the original storage location of the target tag did not form a new support relationship consistent with the adjacent change template after blood bag retrieval. Simultaneously, a record of a closure event after moisture absorption was generated on the directly adjacent edge corresponding to the target tag.

[0159] The controller maintains the target blood bag in stock status within the initial inventory determination window and marks the target blood bag as wet and malfunctioning. The target label is restored after 8 minutes, and the controller removes the wet and malfunctioning status. No outbound records are generated during the entire process.

[0160] During another operation, near-field operation confirmed that the antenna failed to read the target tag due to the blood bag passing too quickly, but the corresponding grid formation was greater than [missing information]. The evidence of weight reduction indicates that the target label is missing from the post-event readable label encoding set, and the adjacent blood bags at the original location of the target label form a new support relationship consistent with the applicable blood bag removal adjacency change template. The controller identifies the target label as the presumed removal node and confirms the removal of the target blood bag based on indirect inventory change evidence.

[0161] When the location grid forms evidence of weight reduction, but two tags fail to be read stably at the same time after the event, and the near-field operation confirms that the antenna only records the code of one tag, and the dynamic adjacency graph cannot uniquely determine whether the other tag has been removed, the controller generates an outbound record for the tag with direct removal evidence, registers the other tag as pending verification status, and outputs the on-site verification task.

[0162] Example 3: This embodiment provides a modular structure for a real-time blood inventory management system based on anti-interference UHF RFID, used to implement the system operation logic described in Embodiment 2. The system modules include a data acquisition module, a reference tag management module, an operated node determination module, a baseline and adjacency graph establishment module, a dynamic adjacency graph update module, a local common-mode change propagation sequence generation module, a moisture-induced closure event generation module, an inventory status confirmation module, an event management module, and a baseline version management module.

[0163] The data acquisition module is used to acquire tag reading data, blood bag storage data, cabinet status data, location grid load-bearing data, near-field operation confirmation data, and temperature and humidity data, and calculates the reading success rate and minimum stable reading power based on the tag reading data.

[0164] The reference label management module is used to create a candidate table of reference labels before inventory event processing, select three valid reference labels (at least one fixed reference label) for each scanning window, and pause the automatic judgment of moisture status based on reference correction when there are fewer than three valid reference labels.

[0165] The module for determining the operated node is used to form direct retrieval evidence or direct supplementary evidence based on near-field operation confirmation records and changes in position grid quality. When direct evidence is missing, it determines the presumed retrieval node or presumed supplementary node based on changes in position grid quality, changes in tag encoding sets, and adjacency change templates.

[0166] The baseline and adjacency graph creation module is used to create an unmodifiable baseline version based on the lowest stable reading power, create an initial adjacency graph based on the position grid number and stacking order, and save adjacency variation templates created according to blood bag specifications, liquid volume range, label affixing area, and stacking layer.

[0167] The dynamic adjacency graph update module is used to calculate the change in the dual-polarization power level difference after reference correction, and update the blood bag nodes and direct adjacent edges according to the operated node, the order of adjacent label changes and the adjacency change template to obtain the dynamic adjacency graph.

[0168] The local common-mode change propagation sequence generation module is used to calculate the dual-polarization average power level change and the local common-mode power level change, and generate the local common-mode change propagation sequence based on the dynamic adjacency graph, open adjacency relationship and the arrival time of the local common-mode change of adjacent tags.

[0169] The wet-induced closure event generation module is used to associate the arrival time of local common-mode change with the closure time of adjacency relationship. When the arrival time of local common-mode change is earlier than the closure of adjacency relationship and the local common-mode power level change continues after closure, a wet-induced closure event record is generated.

[0170] The inventory status confirmation module is used to confirm the status of blood bags as in stock, inbound, outbound, abnormal reading due to moisture, or pending verification, based on the priority of direct inventory change evidence, indirect inventory change evidence, and closure event records after moisture exposure.

[0171] The event management module manages the original event timeline, stability determination timeline, initial inventory determination window, recovery tracking window, related events, and on-site verification tasks. Events corresponding to different blood storage drawers are processed separately, while related events within the same blood storage drawer are processed according to the rules described in Example 2.

[0172] The baseline version management module is used to bind a baseline version that takes effect at the start of each event, generate a new baseline version after the event is closed, and keep the historical baseline version unmodifiable.

[0173] In this embodiment, each module can be implemented by an independent hardware circuit, by a processor executing a corresponding computer program, or by a combination of hardware circuitry and computer program. The specific data processing procedures for each module are the same as the corresponding steps in Embodiment 2, and will not be repeated here.

[0174] Example 4: This embodiment provides an electronic device, including a processor, a memory, a communication interface, and a communication bus. The processor, memory, and communication interface are connected via the communication bus. The communication interface is used for data communication with an RFID reader / writer, a door status sensor, a drawer status sensor, an air temperature sensor, a relative humidity sensor, a support surface temperature sensor, a position grid load-bearing sensor, and a near-field operation confirmation antenna.

[0175] The memory stores computer programs that can be loaded and executed by the processor. The processor executes the operating logic of the real-time blood inventory management system based on anti-interference ultra-high frequency RFID, as described in Embodiment 2, by running the computer program.

[0176] The memory is used to store tag reading data, blood bag storage data, cabinet status data, location grid load-bearing data, near-field operation confirmation data, temperature and humidity data, reference tag candidate table, adjacency change template, minimum stable reading power, baseline version, initial adjacency graph, dynamic adjacency graph, local common mode change propagation sequence, closure event record after moisture exposure, inventory record, and on-site verification record.

[0177] A processor may include one or more processing cores. A processor may be a central processing unit, a microprocessor, a microcontroller, a digital signal processor, an application-specific integrated circuit, a field-programmable gate array, or other device capable of executing computer programs and processing data.

[0178] The memory may include random access memory, read-only memory, flash memory, solid-state drive, hard disk, or other storage devices capable of storing computer programs and data. The communication bus may include an address bus, a data bus, and a control bus.

[0179] This embodiment also provides a computer-readable storage medium storing a computer program. When the computer program is executed by a processor, it implements the operating logic of the real-time blood inventory management system based on anti-interference ultra-high frequency RFID as described in Embodiment 2.

[0180] The computer-readable storage medium may be a hard disk, solid-state drive, random access memory, read-only memory, erasable programmable read-only memory, flash memory, optical disk, USB flash drive, or other media capable of tangibly storing computer programs.

[0181] Those skilled in the art will understand that all or part of the steps implementing the system operation logic of the above embodiments can be accomplished by computer program instructions and related hardware. The computer program can be stored in a computer-readable storage medium and run on a processor to execute the corresponding steps in the above embodiments.

[0182] In the description of this specification, the terms include, encompass, or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, apparatus, or device that includes a list of elements may include not only the elements expressly listed, but also other elements not expressly listed or elements inherent to the process, method, apparatus, or device.

[0183] The above description is merely a specific embodiment of the present invention. Those skilled in the art can combine or substitute the technical features in the above embodiments without departing from the concept of the present invention, and all resulting technical solutions should fall within the protection scope defined by the claims of the present invention.

Claims

1. A real-time blood inventory management system based on anti-interference RFID, characterized in that, include: The data acquisition module is used to acquire tag reading data, blood bag storage data, location grid quality data, near-field operation confirmation data, and temperature and humidity data. The reference label management module is used to determine valid reference labels; The operated node determination module is used to determine the operated node based on the position grid quality data and near-field operation confirmation data; The baseline and adjacency graph establishment module is used to establish the label reading baseline and the initial adjacency graph of the blood bag; The dynamic adjacency graph update module is used to update the initial adjacency graph based on changes in the radio frequency response of the operated node and tag; The local common-mode change propagation sequence generation module is used to generate a local common-mode change propagation sequence based on the local common-mode power level changes of the tag and the updated adjacency graph. The module for generating closure events after moisture exposure is used to generate closure event records after moisture exposure based on the local common mode change propagation sequence and the closure time of the adjacency relationship. The inventory status confirmation module is used to confirm the blood bag inventory status based on the operated node and the closing event record after moisture exposure.

2. The blood real-time inventory management system based on anti-interference RFID according to claim 1, characterized in that, The tag reading data includes the reading results of each blood bag tag under different reading channels, interrogation frequencies, and transmission power levels. The data acquisition module is used to determine the minimum stable reading power of the blood bag tag to reach the stable reading rate threshold under each reading channel and interrogation frequency based on the reading success rate under each transmission power level, and to mark the minimum stable reading power that does not reach the stable reading rate threshold as missing.

3. A real-time blood inventory management system based on anti-interference RFID according to claim 2, characterized in that, The reference label management module is used to create a reference label candidate table and determine three valid reference labels from the reference label candidate table in each scanning window. At least one of the three valid reference labels is a fixed reference label. A fixed reference tag is used to correct for variations in the dual-polarization power level difference of the blood bag tag, while an effective reference tag is used to correct for variations in the average dual-polarization power level of the blood bag tag.

4. A real-time blood inventory management system based on anti-interference RFID according to claim 1, characterized in that, The module for determining the operated node is used to match the tag encoding and reading time in the near-field operation confirmation data with the changes in the quality of the location grid. When the matching result is unique, the blood bag node corresponding to the matched tag is determined as the operated node. When the matching result is not unique or the near-field operation confirmation data is missing, the operated node is determined based on the consistency of the changes in the quality of the location grid, the changes in the tag set, and the changes in adjacency. If the operated node cannot be uniquely determined, a record to be verified is generated.

5. A real-time blood inventory management system based on anti-interference RFID according to claim 2, characterized in that, The baseline and adjacency graph establishment module is used to establish a tag reading baseline based on the lowest stable reading power of multiple scanning windows when the blood bag storage status is stable, and to establish an initial adjacency graph based on the position grid number and the stacking order of blood bags. The initial adjacency graph includes blood bag nodes corresponding to the blood bags and direct adjacency edges used to represent the contact relationship between adjacent blood bags.

6. A real-time blood inventory management system based on anti-interference RFID according to claim 5, characterized in that, The dynamic adjacency graph update module is used to determine the open or closed adjacency relationship of directly adjacent edges based on the operated node, the change of the dual-polarization power level difference after reference correction, the change order of adjacent labels, and the pre-established adjacency change template, and to record the opening time and closing time of the adjacency relationship.

7. A real-time blood inventory management system based on anti-interference RFID according to claim 6, characterized in that, The local common-mode change propagation sequence generation module is used to determine the local common-mode power level change of each blood bag tag within the coagulation risk time interval based on the reference-corrected dual-polarization average power level change. The time when the local common-mode power level change satisfies the conditions of unidirectional change at multiple interrogation frequency points and the persistence condition is determined as the arrival time of the local common-mode change. Based on the updated adjacency graph and the arrival time of the local common-mode change of each blood bag tag, a local common-mode change propagation sequence is generated.

8. A real-time blood inventory management system based on anti-interference RFID according to claim 7, characterized in that, The wet-induced closure event generation module is used to determine the earlier arrival time of the local common mode change in the blood bag labels on both sides of the direct adjacent edge when the direct adjacent edge changes from an open adjacent relationship to a closed adjacent relationship. When the arrival time of the local common mode change is earlier than the closing time of the adjacent relationship, and the change in local common mode power level remains unchanged after closure and meets the persistence condition, a wet-induced closure event record is generated.

9. A real-time blood inventory management system based on anti-interference RFID according to claim 8, characterized in that, The inventory status confirmation module is used to confirm the outbound or inbound status of the corresponding blood bag when the operated node has evidence of blood bag removal or blood bag replenishment; when there is no evidence of blood bag removal or blood bag replenishment, and the blood bag label has a record of a closure event after getting wet and has not reached a stable reading rate threshold, the module maintains the inbound status of the corresponding blood bag and marks the reading as abnormal. When evidence conflicts or the blood bag label cannot be uniquely identified, a verification record is generated.

10. A real-time blood inventory management system based on anti-interference RFID according to claim 1, characterized in that, It also includes an event management module and a baseline version management module; The event management module is used to set a unique event identifier for each retrieval event and associate it with the event start and end times, the operated node, the change in the location grid quality, near-field operation confirmation data, valid reference tags, tag reading baseline, the arrival time of local common mode change, the closing time of adjacency relationship, and the closing event record after moisture exposure. The baseline version management module is used to bind the retrieval event with the tag reading baseline version that took effect at the start of the retrieval event, and to create a tag reading baseline version for subsequent retrieval events after the retrieval event ends.

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