A library high-density book management system and a management method thereof

Abstract

The application discloses a library high-density book management system and a management method thereof, and belongs to the field of library management. The library high-density book management system comprises a multi-mode SAW sensing label, a reader-writer head terminal, and a regional controller. The reader-writer head terminal is arranged at the top center of each bookshelf unit at an interval of 3-5 meters. The reader-writer head terminal is composed of a small linear array of 4-8 microstrip patch antennas, generates high-frequency pulses, and receives reflected signals, and is used for accurately measuring echo arrival time and phase. The regional controller is arranged in each reading room or area, and is responsible for managing all reader-writer head terminals in the area. The regional controller is a controller with a built-in FPGA, and realizes real-time beam control and signal processing. The application realizes passive sensing of the physical state of books, and realizes high-precision positioning through a beam arrival time difference.

Description

Technical Field

[0001] This invention belongs to the field of library management technology, specifically, it relates to a high-density library book management system and its management method. Background Technology

[0002] Currently, the mainstream technology for library book management is ultra-high frequency radio frequency identification (UHF RFID) technology. Its basic working principle is: the reader emits electromagnetic waves to power a passive tag, and the tag sends its stored ID information back to the reader through backscatter modulation.

[0003] However, in the specific application scenario of high-density book collections in libraries, UHF RFID technology based on the principle of electromagnetic backscattering has exposed the following inherent and difficult-to-overcome technical defects:

[0004] Poor adaptability to electromagnetic environments and low read reliability:

[0005] Metal interference: Library bookshelves are mostly made of metal, which has a strong reflection and shielding effect on electromagnetic waves, resulting in blind spots for reading and writing. Books placed with their metal surfaces touching are very easy to miss.

[0006] Medium absorption: Books themselves are made of paper (rich in cellulose and polar) and ink, which have a significant absorption and attenuation effect on electromagnetic waves. The thicker and more humid the book, the more severe the signal attenuation and the more drastically the reading distance decreases.

[0007] Multipath effect: The dense bookshelf creates a complex multipath reflection environment, causing signals to superimpose or cancel each other out, making the read signal strength (RSSI) extremely unstable and unusable for reliable positioning.

[0008] Collision problems are severe at high densities, leading to low inventory efficiency.

[0009] Tag collision: When a reader attempts to read a large number of tags on a bookshelf, the simultaneous responses from numerous tags cause signal interference, making it impossible for the reader to parse them. Although anti-collision algorithms (such as ALOHA) exist, the inventory time becomes extremely long at extreme densities of hundreds or thousands of tags.

[0010] Reader collision: When the working domains of multiple readers overlap, co-channel interference will occur, requiring complex space division multiple access or time division multiple access scheduling, which increases system complexity and cost.

[0011] It has limited functionality and lacks the ability to perceive physical states.

[0012] Traditional RFID tags are simply identity cards, with static ID information stored in their chips.

[0013] It cannot perceive the dynamic physical state of books, for example:

[0014] Whether it has been retrieved and viewed: Cannot be detected automatically in real time.

[0015] Temperature and humidity of the storage environment: These are crucial for the preservation of precious ancient books, but current technology cannot monitor them on every single book.

[0016] Whether it suffered severe shaking or falling: Unable to record.

[0017] Low positioning accuracy makes it difficult to accurately identify misplaced items.

[0018] The location method based on electromagnetic signal strength (RSSI) is severely affected by the aforementioned multipath and attenuation, and the positioning accuracy is usually above 1 meter. It cannot accurately locate the specific floor or book position, making it difficult to find misplaced books. Summary of the Invention

[0019] To address the shortcomings of existing technologies, the present invention aims to provide a high-density book management system for libraries and its management method.

[0020] To achieve the aforementioned objectives, the technical solution adopted by this invention includes: a high-density book management system for libraries, comprising:

[0021] The multimodal SAW sensing tag includes a substrate made of 128° YX-cut lithium tantalate. A reference channel and a sensing channel are arranged on the substrate. The reference channel consists of a set of hermetically sealed reflective gratings and a layer of UV-curable adhesive that tightly covers and seals the area, forming a vacuum chamber or inert gas chamber completely isolated from external humidity and stress; its water and oxygen permeability is less than 10%. -3 g / m 2 / day, ensuring internal atmosphere stability under normal conditions for five years, sufficient to provide a reliable temperature reference. The sensing channel consists of a set of reflective gratings and a layer of graphene oxide coated on the grating area; the multimodal SAW sensing tags are adhered to the spine of the book using a highly viscoelastic, highly sensitive strain adhesive (such as polyurethane-based pressure-sensitive adhesive). Any slight bending of the spine (when removed) or vibration is effectively transmitted to the entire SAW tag substrate through this adhesive, causing macroscopic deformation of the substrate; at least five multimodal SAW sensing tags are fixedly installed at the four corners and center of each bookshelf as fixed reference tags. The IDs and precise coordinates of these tags are pre-entered into the system database; the fixed reference tags are packaged in the same way as the book tags, but their attachment positions are ensured to be immovable, thus providing a known and stable calibration source for the ASTC-BF algorithm;

[0022] The reader head is deployed at the top center of each bookshelf unit, with one reader every 3-5 meters. The reader head consists of a small linear array of 4-8 microstrip patch antennas, which generate high-frequency pulses and receive reflected signals for precise measurement of echo arrival time (ToF) and phase.

[0023] Each reading room or area has one area controller, which is responsible for managing all reader heads within that area. The area controller is a controller with a built-in FPGA, which runs an adaptive space-time coding beamforming algorithm and differential measurement and calculation to achieve real-time beam control and signal processing.

[0024] The central server stores global data, manages task queues, and provides a user interface.

[0025] A method for managing high-density books in a library includes:

[0026] S1. The area controller drives the reader head to scan the multimodal SAW sensor tags on the bookshelf and runs the Adaptive Space-Time Coding Beamforming (ASTC-BF) algorithm to perform channel estimation and calibration in order to eliminate environmental multipath interference.

[0027] S2. The controller generates a sequence of focal coordinates in the three-dimensional space of the bookshelf, and drives the reader head to perform beamforming projection on each focal point in sequence, thereby activating the multimodal SAW sensor tag on each book in turn.

[0028] S3. The reader head receives and digitizes the return signal from the multimodal SAW sensor tag (which contains two distinguishable reflected pulses from the reference channel and the sensor channel, and uploads them to the area controller).

[0029] S4. The controller performs differential measurement and calculation on each signal as follows:

[0030] a. Signal separation and ID decoding: From the complex echo signal, the pulses from the reference channel and the sensor channel are separated through a time window; the unique ID of the book is decoded from the time interval of the pulses.

[0031] b. Positioning calculation: Centimeter-level positioning is achieved by using the focal coordinates (known) of beamforming and the time of arrival (ToF).

[0032] c. Phase information extraction: Accurately calculate the phase offset of the reference channel pulse. Phase offset of the sensing channel pulse .

[0033] d. Difference computation and multi-parameter decoupling:

[0034] Temperature calculation: ,in, The temperature sensitivity coefficient of the pre-calibrated reference channel.

[0035] Calculate mixed signals: -( ) ,in, (This refers to the pre-calibrated temperature sensitivity coefficient of the sensing channel). This operation counteracts the effect of temperature on the sensing channel, resulting in... This is solely the result of the combined effects of humidity and strain.

[0036] Time-frequency analysis decoupling: for The signal is subjected to a short-time Fourier transform (STFT) to decompose it into components of different frequencies.

[0037] Extract the intensity of its low-frequency components using the formula Calculate the humidity change ,in, This is the humidity sensitivity coefficient.

[0038] Extract the intensity of its high-frequency components. If it exceeds the preset threshold, it is determined that a strain event ε has occurred (i.e., the book is moved or vibrated).

[0039] S5. Status Assessment and Alarms:

[0040] If a high-frequency strain event is detected in step d of step 4, the book is marked as either removed or being read.

[0041] If the solution is If the threshold / high humidity is set, an alarm for excessively high ambient humidity will be sent.

[0042] If the ID is not at the expected coordinates in the database, a misplacement alarm will be generated;

[0043] S6. Package and upload all book data, including ID, coordinates, temperature, humidity, and real-time status (normal / removed / misplaced), to the central server, update the database, and complete a high-precision, full-status inventory.

[0044] This invention abandons the traditional antenna-based electromagnetic backscatter RFID technology and innovatively adopts surface acoustic wave (SAW) tags as data carriers, and designs a multi-reader collaborative beamforming read / write network. This system not only completely solves the electromagnetic interference problem, but also enables passive sensing of the physical state of books, and achieves high-precision positioning through time difference of arrival (TDoA).

[0045] Further, in step S1, the area controller drives the reader head to scan the multimodal SAW sensor tags on the bookshelf, and runs the Adaptive Space-Time Coding Beamforming (ASTC-BF) algorithm for channel estimation and calibration to eliminate environmental multipath interference, including:

[0046] Periodically, all reader heads transmit probe signals in omnidirectional mode to collect signals from multimodal SAW sensor tags on the bookshelf. These tags are located in known positions and are used to calibrate channel disturbances caused by environmental changes (such as temperature or movement of people).

[0047] Based on the response of the reference tag, the area controller estimates the channel transmission function H(f) from each reader antenna element to any point (x,y,z) in space;

[0048] When a book needs to be queried at coordinates (x, y, z), the controller solves for a set of complex weighting coefficients W (including amplitude and phase) to ensure that the signals transmitted by all antenna elements are superimposed in phase at the target point, maximizing energy. Its mathematical expression is:

[0049] in, This is the optimal beamforming weight vector. To reduce real-time computational complexity, the system employs a pre-defined codebook mechanism. During the deployment phase, the optimal beamforming weight vector corresponding to the discrete focal coordinates covering the entire bookshelf space is pre-calculated and stored through measurement or electromagnetic simulation. The data is stored in the look-up table. During runtime, the area controller only needs to retrieve the corresponding weight vector W from the look-up table based on the current target focus coordinates and send it to each reader head to achieve millisecond-level beam switching, thereby meeting real-time requirements.

[0050] To address the multipath effect, the transmitted pulse is space-time coded, resulting in a sharper main lobe and better sidelobe suppression.

[0051] It achieves precise energy projection onto a single book, preventing other tags from being activated due to insufficient energy reception, thus completely resolving tag collision and reader collision issues. Simultaneously, the highly directional beam has stronger penetration power, overcoming electromagnetic shielding and attenuation.

[0052] Compared with the prior art, the advantages of the present invention include:

[0053] (1) The present invention provides a library high-density book management system and management method, which provides a brand-new book tag technology that is insensitive to metal bookshelves and the book medium itself, and fundamentally overcomes the attenuation, reflection and multipath effect of electromagnetic waves in complex environments;

[0054] (2) The present invention provides a library high-density book management system and its management method, which provides a new reading and writing mechanism that can accurately project energy and read information from a single book, fundamentally eliminating tag collisions and reader collisions, making inventory efficiency independent of book density, and greatly improving inventory speed.

[0055] (3) The present invention provides a library high-density book management system and management method, which provides an intelligent tag that integrates identity recognition and multi-parameter sensing, so that while providing a unique ID, it can passively and in real time sense the temperature, humidity and physical state changes of books such as whether they have been moved, taken out or vibrated.

[0056] (4) The present invention provides a high-density book management system and management method for libraries, which can realize the precise positioning of books at the shelf level (centimeter level), thereby automatically and in real time detecting and reporting misplaced books. Attached Figure Description

[0057] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0058] Figure 1 This is a schematic diagram of the system circuit of a high-density library book management system and its management method according to the present invention. Detailed Implementation

[0059] In view of the shortcomings of the prior art, the inventors of this invention, through long-term research and extensive practice, have proposed the technical solution of this invention. The technical solution, its implementation process, and principles will be further explained below with reference to the accompanying drawings and specific implementation examples in the embodiments of this application.

[0060] It should be noted that the embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention. The described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, the present invention covers any substitutions, modifications, equivalent methods and solutions made on the spirit, principles and scope of the present invention as defined by the claims. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0061] In the description of this application, the terms "first," "second," "third," and similar terms do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, the terms "one" or "a" do not indicate a quantity limitation, but rather indicate the presence of at least one. Terms such as "include" or "contain" mean that the elements or objects preceding "include" cover the elements or objects listed following "include" or their equivalents, and do not exclude other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect.

[0062] In the description of this application, the terms center, up, down, front, back, left, right, vertical, horizontal, top, bottom, inside, outside, etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. In addition, when using positional terms such as sides, outer side, top and bottom, etc., it should be understood that they are used only for the convenience of understanding and description, taking into account that the structure may be oriented to other positions.

[0063] In the description of this application, unless otherwise expressly specified and limited, the technical or scientific terms used shall have the ordinary meaning understood by a person with ordinary skills in the art to which this application pertains. Terms such as installation, connection, and linking shall be interpreted broadly, for example, they may refer to fixed connection, detachable connection, mating connection, or integral connection. For a person skilled in the art, the specific meaning of the above terms in this application may be understood according to the specific circumstances.

[0064] The present invention aims to introduce and explain the structural composition of a high-density library book management system and its management method, as well as the cooperative relationship between the various components. Unless otherwise specified, the dimensions, materials, and manufacturing processes of the various components suitable for the high-density library book management system and its management method in the present invention can be selected according to specific circumstances, and no special limitations or explanations are made here.

[0065] Furthermore, to provide the public with a better understanding of the present invention, certain specific details are described in detail in the following description of the invention. However, those skilled in the art will fully understand the invention even without these detailed descriptions.

[0066] Example 1

[0067] Please see Figure 1 A high-density book management system for libraries, comprising:

[0068] The multimodal SAW sensor tag includes a substrate made of 128° YX-cut lithium tantalate (this cut has a high electromechanical coupling coefficient and excellent temperature stability), providing an acoustic wave transmission channel and temperature sensitivity. A reference channel and a sensing channel are arranged on the substrate. The reference channel consists of a set of hermetically sealed reflective gratings and a layer of UV-curable adhesive that tightly covers and seals this area (this adhesive has extremely low permeability to water vapor and gas, sufficient to provide a stable reference environment throughout the tag's lifespan), forming a vacuum chamber or inert gas chamber completely isolated from external humidity and stress. This provides a pure temperature reference signal for the entire system; its water and oxygen permeability is less than 10%. -3 g / m 2 / day, ensuring internal atmosphere stability under normal conditions for five years, sufficient to provide a reliable temperature reference. The sensing channel consists of a set of reflective gratings coated with a layer of graphene oxide in the grating area. This type of material has extremely strong hydrophilicity, undergoes significant volume expansion upon absorbing water, and its own elastic modulus also changes dramatically, generating a significant surface loading and strain effect on the underlying SAW substrate, thereby greatly altering the propagation speed and attenuation of surface acoustic waves. The multimodal SAW sensing tags are adhered to the spine of the book using a highly viscoelastic, highly sensitive strain adhesive (such as polyurethane-based pressure-sensitive adhesive). Any slight bending of the spine (when removed) or vibration is effectively transmitted to the entire SAW tag substrate through this adhesive, causing macroscopic deformation of the substrate. At least five multimodal SAW sensing tags are fixedly installed at the four corners and center of each bookshelf as fixed reference tags. The IDs and precise coordinates of these tags are pre-entered into the system database. The fixed reference tags are packaged in the same way as the book tags, but their attachment positions are ensured to be immovable, thus providing a known and stable calibration source for the ASTC-BF algorithm.

[0069] The reader head is deployed at the top center of each bookshelf unit, with one reader every 3-5 meters. The reader head consists of a small linear array of 4-8 microstrip patch antennas, which generate high-frequency pulses and receive reflected signals for precise measurement of echo arrival time (ToF) and phase.

[0070] Each reading room or area has one area controller, which is responsible for managing all reader heads within that area. The area controller is a controller with a built-in FPGA, which runs an adaptive space-time coding beamforming algorithm and differential measurement and calculation to achieve real-time beam control and signal processing.

[0071] The central server stores global data, manages task queues, and provides a user interface.

[0072] A method for managing high-density books in a library includes:

[0073] S1. The area controller drives the reader head to scan the multimodal SAW sensor tags on the bookshelf and runs the Adaptive Space-Time Coding Beamforming (ASTC-BF) algorithm to perform channel estimation and calibration in order to eliminate environmental multipath interference.

[0074] S2. The controller generates a sequence of focal coordinates in the three-dimensional space of the bookshelf, and drives the reader head to perform beamforming projection on each focal point in sequence, thereby activating the multimodal SAW sensor tag on each book in turn.

[0075] S3. The reader head receives and digitizes the return signal from the multimodal SAW sensor tag (which contains two distinguishable reflected pulses from the reference channel and the sensor channel), and uploads it to the area controller.

[0076] S4. The controller performs differential measurement and calculation on each signal as follows (this is an automated signal processing pipeline that is completed in real time in the FPGA or high-speed processor of the area controller):

[0077] a. Signal separation and ID decoding: From the complex echo signal, the pulses from the reference channel and the sensor channel are separated through a time window; the unique ID of the book is decoded from the time interval of the pulses.

[0078] b. Positioning calculation: Centimeter-level positioning is achieved by using the focal coordinates (known) of beamforming and the time of arrival (ToF).

[0079] c. Phase information extraction: Accurately calculate the phase offset of the reference channel pulse. Phase offset of the sensing channel pulse .

[0080] d. Difference computation and multi-parameter decoupling:

[0081] Temperature calculation: ,in, The temperature sensitivity coefficient of the pre-calibrated reference channel.

[0082] Calculate mixed signals: -( ) ,in, This represents the pre-calibrated temperature sensitivity coefficient of the sensing channel. This operation counteracts the effect of temperature on the sensing channel, resulting in... This is solely the result of the combined effects of humidity and strain.

[0083] Time-frequency analysis decoupling: for The signal is subjected to a short-time Fourier transform (STFT) to decompose it into components of different frequencies.

[0084] Extract the intensity of its low-frequency components using the formula Calculate the humidity change ,in, This is the humidity sensitivity coefficient.

[0085] Extract the intensity of its high-frequency components. If it exceeds the preset threshold, it is determined that a strain event ε has occurred (i.e., the book is moved or vibrated).

[0086] S5. Status Assessment and Alarms:

[0087] If a high-frequency strain event is detected in step d of step 4, the book is marked as either removed or being read.

[0088] If the solution is If the threshold / high humidity is set, an alarm for excessively high ambient humidity will be sent.

[0089] If the ID is not at the expected coordinates in the database, a misplacement alarm will be generated;

[0090] S6. Package and upload all book data, including ID, coordinates, temperature, humidity, and real-time status (normal / removed / misplaced), to the central server, update the database, and complete a high-precision, full-status inventory.

[0091] Further, in step S1, the area controller drives the reader head to scan the multimodal SAW sensor tags on the bookshelf, and runs the Adaptive Space-Time Coding Beamforming (ASTC-BF) algorithm for channel estimation and calibration to eliminate environmental multipath interference, including:

[0092] Periodically, all reader heads transmit probe signals in omnidirectional mode to collect signals from multimodal SAW sensor tags on the bookshelf. These tags are located in known positions and are used to calibrate channel disturbances caused by environmental changes (such as temperature or movement of people).

[0093] Based on the response of the reference tag, the area controller estimates the channel transmission function H(f) from each reader antenna element to any point (x,y,z) in space;

[0094] When a book needs to be queried at coordinates (x, y, z), the controller solves for a set of complex weighting coefficients W (including amplitude and phase) to ensure that the signals transmitted by all antenna elements are superimposed in phase at the target point, maximizing energy. Its mathematical expression is:

[0095] in, This is the optimal beamforming weight vector. To reduce real-time computational complexity, the system employs a pre-defined codebook mechanism. During the deployment phase, the optimal beamforming weight vector corresponding to the discrete focal coordinates covering the entire bookshelf space is pre-calculated and stored through measurement or electromagnetic simulation. The data is stored in the look-up table. During runtime, the area controller only needs to retrieve the corresponding weight vector W from the look-up table based on the current target focus coordinates and send it to each reader head to achieve millisecond-level beam switching, thereby meeting real-time requirements.

[0096] To address the multipath effect, the transmitted pulse is space-time coded, resulting in a sharper main lobe and better sidelobe suppression.

[0097] It achieves precise energy projection onto a single book, preventing other tags from being activated due to insufficient energy reception, thus completely resolving tag collision and reader collision issues. Simultaneously, the highly directional beam has stronger penetration power, overcoming electromagnetic shielding and attenuation.

[0098] Understandable,

[0099] In some conditions, the properties of the graphene oxide (GO) film itself can change with temperature, so the system of this invention has a periodic self-calibration function. When the facility is closed late at night, after controlling the ambient humidity to stabilize for a period of time, the reader can be driven to scan all tags. At this time, it is assumed that no strain events have occurred (ε=0) and the humidity is uniform (ΔH≈0), and the system records the values ​​of each tag at this time. and The temperature sensitivity coefficient of the sensing channel is updated online using a linear regression algorithm. This compensates for parameter drift caused by material aging and ensures the accuracy of long-term measurements.

[0100] It should be understood that the above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. It should not be considered that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, several simple deductions or substitutions can be made without departing from the concept of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the protection scope of the present invention.

Claims

1. A high-density book management system for libraries, characterized in that: include: A multimodal SAW sensor tag includes a substrate made of 128° YX-cut lithium tantalate. A reference channel and a sensing channel are arranged on the substrate. The reference channel consists of a set of hermetically sealed reflective gratings and a layer of UV-curable adhesive that tightly covers and seals the reference channel. The sensing channel consists of a set of reflective gratings and a layer of graphene oxide coated on the reflective grating area. The multimodal SAW sensor tag is adhered to the spine of a book using a highly viscoelastic and highly sensitive strain adhesive. Any minute bending or vibration of the spine is effectively transmitted to the entire SAW tag substrate through this adhesive, causing macroscopic deformation of the substrate. At least five multimodal SAW sensor tags are fixedly installed at the four corners and the center of each bookshelf as fixed reference tags. The reader head is deployed at the top center of each bookshelf unit, with one reader head every 3-5 meters; the reader head consists of a small linear array of 4-8 microstrip patch antennas, which generates high-frequency pulses and receives reflected signals for accurate measurement of echo arrival time and phase. Each reading room or area has one area controller, which is responsible for managing all reader heads within that area. The area controller is a controller with a built-in FPGA to realize real-time beam control and signal processing. The central server stores global data, manages task queues, and provides a user interface; The following management steps are included: S1. The area controller drives the reader head to scan the multimodal SAW sensor tags on the bookshelf and runs an adaptive space-time coding beamforming algorithm to perform channel estimation and calibration in order to eliminate environmental multipath interference. S2. The controller generates a sequence of focal coordinates in the three-dimensional space of the bookshelf, and drives the reader head to perform beamforming projection on each focal point in sequence, thereby activating the multimodal SAW sensor tag on each book in turn. S3. The reader head receives the return signal from the multimodal SAW sensor tag, which contains two distinguishable reflected pulses from the reference channel and the sensing channel, and digitizes it, then uploads it to the area controller. S4. The controller performs differential measurement and calculation on each signal as follows: a. Signal separation and ID decoding: Separate the pulses from the reference channel and the sensor channel from the complex echo signal through a time window; decode the unique ID of the book from the timing interval of the pulses; b. Positioning calculation: Centimeter-level positioning is achieved by using the focal coordinates of beamforming and the echo arrival time; c. Phase information extraction: Accurately calculate the phase offset of the reference channel pulse. Phase offset of the sensing channel pulse ; d. Difference calculation and multi-parameter decoupling: Temperature calculation: ,in, The temperature sensitivity coefficient of the pre-calibrated reference channel. This is the calculated temperature value. Calculate mixed signals: -( ) ,in, The temperature sensitivity coefficient of the pre-calibrated sensing channel. To calculate the mixed signal value, Time-frequency analysis decoupling: for The signal is decomposed into components of different frequencies by performing a short-time Fourier transform. Extract the intensity of its low-frequency components using the formula Calculate the humidity change ,in, This is the humidity sensitivity coefficient. The intensity of the low-frequency component. Extract the intensity of its high-frequency components. If it exceeds a preset threshold, it is determined that a strain event ε has occurred at this moment. S5. Status Assessment and Alarms: If a high-frequency strain event is detected in step d of step 4, then the book is marked as either removed or being read. If the solution is If the threshold / high humidity is set, an alarm for excessively high ambient humidity will be sent. If the ID is not at the expected coordinates in the database, a misplacement alarm will be generated; S6. Package and upload all book IDs, coordinates, temperature, humidity, and real-time status data to the central server, update the database, and complete a high-precision, full-status inventory.

2. The high-density book management system for libraries according to claim 1, characterized in that: Step S1, where the area controller drives the reader head to scan the multimodal SAW sensor tags on the bookshelf and runs an adaptive space-time coding beamforming algorithm for channel estimation and calibration to eliminate environmental multipath interference, includes: F1. Periodically enable all reader heads to emit detection signals in omnidirectional mode to collect signals from multimodal SAW sensor tags on the bookshelf; F2. The area controller estimates the channel transmission function H(f) from each reader antenna element to any point (x,y,z) in space based on the response of the reference tag. F3. When querying a book at coordinates (x, y, z), the controller calculates a set of complex weighting coefficients W such that the signals transmitted by all antenna elements are superimposed in phase at the target point, maximizing energy. Its mathematical expression is: in, This is the optimal beamforming weight vector.

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