RFID tag adaptive separation system and packaging method for multi-medium environment

Abstract

The application discloses a multi-medium environment-oriented RFID tag adaptive separation system and packaging method, and belongs to the field of radio frequency identification technology.The system is composed of a multi-band reconfigurable antenna array, an embedded environment sensing module, an adaptive impedance tuning circuit and an intelligent control unit, through real-time detection of medium dielectric constant and electromagnetic loss parameters, dynamic adjustment of working frequency and impedance matching state, optimal energy transmission in a multi-medium environment is realized.The packaging method adopts a multi-layer composite structure design, combines a flexible base and gradient dielectric material, optimizes an antenna radiation pattern through three-dimensional electromagnetic field simulation, and introduces an electromagnetic shielding isolation layer to reduce environmental coupling interference.The scheme effectively improves the label recognition rate and communication distance in a complex medium scene, and simultaneously has self-repairing protective coating and low power consumption characteristics, and can be widely applied to the fields of industrial Internet of Things, intelligent logistics and special environment monitoring.

Description

Technical Field

[0001] This invention relates to the field of radio frequency identification technology, and in particular to an adaptive separation system and packaging method for RFID tags in multi-media environments. Background Technology

[0002] Radio Frequency Identification (RFID) technology, as a core component of the sensing layer of the Internet of Things (IoT), has been widely applied in logistics tracking, asset management, and industrial automation. However, traditional RFID tags suffer from severe signal attenuation and reading stability defects in multi-medium environments composed of metals, liquids, and heterogeneous materials due to electromagnetic wave reflection, dielectric loss, and impedance mismatch. Existing technologies mainly mitigate environmental interference by optimizing antenna structures (such as adding isolation layers or using flexible substrates) or selecting high-dielectric materials, but these methods generally suffer from fixed frequency bands, poor adaptability, and high manufacturing costs, making it difficult to meet the dynamic requirements of complex scenarios.

[0003] A Chinese invention patent discloses an "anti-metal RFID tag and its preparation method," which employs a multilayer ceramic dielectric substrate and a ring-shaped slot antenna design, by increasing the dielectric constant of the substrate (…). ≥10) Reduce eddy current loss on metal surfaces. However, this scheme still has significant drawbacks: (1) The antenna resonant frequency is fixed and the operating frequency band cannot be dynamically adjusted according to the characteristics of the environmental medium; (2) The reliance on a high dielectric constant substrate leads to an increase in tag thickness (>2mm), making it difficult to fit curved metal surfaces; (3) The electromagnetic coupling effect in liquid environments is not considered, resulting in reading distance fluctuations exceeding 40% in mixed media scenarios. The above problems indicate that static design relying solely on structural optimization is insufficient to meet the dynamic adaptation requirements in multi-media environments.

[0004] Based on the analysis of existing technologies, the current technical bottlenecks of RFID tags in multi-media environments can be summarized as follows: (1) Insufficient dynamic compensation for impedance mismatch: heterogeneous media such as metals and liquids cause real-time offset between antenna impedance and chip impedance, and traditional matching networks cannot respond quickly; (2) Poor frequency band coverage and radiation pattern adaptability: fixed frequency band designs are easily interfered with in complex electromagnetic environments, and the radiation pattern is difficult to adaptively optimize; (3) Low environmental compatibility of packaging structure: existing packaging materials are sensitive to temperature, humidity and mechanical stress, and lack gradient dielectric and self-healing protection capabilities. These problems seriously restrict the in-depth application of RFID technology in fields such as industrial Internet of Things and special monitoring, and an all-round solution integrating environmental perception, dynamic tuning and intelligent packaging is urgently needed. Summary of the Invention

[0005] In view of the aforementioned existing problems, the present invention is proposed.

[0006] Therefore, this invention provides an adaptive separation system and packaging method for RFID tags in multi-media environments, which solves the problems of impedance mismatch, frequency band rigidity and poor packaging reliability of RFID tags in multi-media environments.

[0007] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0008] In a first aspect, the present invention provides an adaptive RFID tag separation system for multi-media environments, comprising:

[0009] A multi-band reconfigurable antenna array, consisting of N radiating elements, has resonant frequencies that satisfy:

[0010]

[0011] in, The length of the nth radiating element. where c is the equivalent dielectric constant and c is the speed of light.

[0012] An embedded environment sensing module is used to detect the dielectric constant of the medium in which the tag is located. and loss factor Its output parameters satisfy:

[0013]

[0014] in, This is the measured capacitance. Where A is the dielectric thickness, A is the electrode area, and G is the conductivity. Angular frequency;

[0015] The adaptive impedance tuning circuit adjusts the antenna input impedance in real time through a varactor diode array. To make it compatible with the chip impedance Matching, satisfying:

[0016]

[0017] in, Let be the conjugate complex number of the chip impedance. This is the equivalent resistance of the chip. This is the equivalent reactance of the chip;

[0018] The intelligent control unit, based on data from the embedded environmental perception module, dynamically selects the optimal operating frequency band and impedance matching parameters through a particle swarm optimization algorithm.

[0019] As a preferred embodiment of the RFID tag adaptive separation system for multi-media environments described in this invention, the multi-band reconfigurable antenna array adopts a serpentine folded dipole structure, and the spacing between adjacent radiating elements is... satisfy:

[0020]

[0021] in, Where N is the minimum operating frequency of the system, and N is the number of radiating elements. The maximum wavelength corresponds to the lowest operating frequency supported by the system, and c is the speed of light.

[0022] As a preferred embodiment of the RFID tag adaptive separation system for multi-media environments described in this invention

[0023] The solution includes an embedded environmental sensing module that integrates a temperature compensation circuit, the dielectric constant of which is corrected using the following formula:

[0024]

[0025] Where T is the ambient temperature. For reference temperature, = is the temperature coefficient of the dielectric constant.

[0026] As a preferred embodiment of the RFID tag adaptive separation system for multi-media environments described in this invention, the adaptive impedance tuning circuit includes a π-type matching network, the matching parameters of which are determined by the following formula:

[0027]

[0028] in, This is the antenna's equivalent resistance. This is the chip's equivalent resistance. This is the equivalent reactance of the chip. Where ω is the angular frequency, L is the inductance value in the matching network, and C is the capacitance value in the matching network.

[0029] As a preferred embodiment of the RFID tag adaptive separation system for multi-media environments described in this invention, the intelligent control unit employs a dynamic weighted fusion algorithm, the objective function of which is:

[0030]

[0031] in, For received power, Antenna quality factor, Power threshold, This represents the minimum antenna quality factor required by the system. It is a dynamic weighting factor used to balance the optimized weights between received power and antenna quality factor.

[0032] As a preferred embodiment of the RFID tag adaptive separation system for multi-media environments described in this invention, the system supports a multi-tag collision avoidance protocol with a random backoff time. satisfy:

[0033]

[0034] Where retry represents the number of retries, and BW represents the channel bandwidth. This represents the maximum received signal strength value among all tag signals detected in the current communication scenario. This represents the signal strength value detected by the reader for a specific tag in the most recent communication.

[0035] As a preferred embodiment of the RFID tag encapsulation method for multi-media environments described in this invention,

[0036] This includes the following steps:

[0037] S1. Antenna radiating elements are printed on a flexible polyimide substrate, where the substrate thickness t1 satisfies...

[0038]

[0039] in, The dielectric constant of the substrate is 1. The free-space wavelength of the antenna at the target's operating frequency;

[0040] S2. Covered with a gradient dielectric material layer, the dielectric constant of which is distributed exponentially along the thickness direction:

[0041]

[0042] Where k is the attenuation coefficient, The total thickness of the gradient layer, It is the minimum dielectric constant;

[0043] S3. Add an electromagnetic shielding isolation layer, the surface impedance of which satisfy:

[0044]

[0045] in, For the intrinsic impedance of free space, The electrical conductivity of the shielding material;

[0046] S4. Apply a self-healing protective coating, the thickness of which is... With dielectric loss satisfy:

[0047] .

[0048] As a preferred embodiment of the RFID tag encapsulation method for multi-media environments described in this invention, the gradient dielectric material layer is composed of barium strontium titanate (BST) and polytetrafluoroethylene (PTFE) in a volume ratio V BST :V PTFE =(1:9)∼(4:6) composite, its dielectric constant adjustment range is 2.1≤ ≤120.

[0049] As a preferred embodiment of the RFID tag encapsulation method for multi-media environments described in this invention, the electromagnetic shielding layer is a silver-plated nylon mesh with a mesh aperture of... satisfy:

[0050]

[0051] As a preferred embodiment of the RFID tag encapsulation method for multi-media environments described in this invention, the self-healing protective coating comprises microencapsulated siloxane material with a rupture threshold pressure. satisfy:

[0052]

[0053] in, denoted as the microcapsule radius.

[0054] In a second aspect, the present invention provides a computer device including a memory and a processor, wherein the memory stores a computer program, wherein the computer program, when executed by the processor, implements any step of the RFID tag encapsulation method for multi-media environments as described in the first aspect of the present invention.

[0055] Thirdly, the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein: when the computer program is executed by a processor, it implements any step of the RFID tag encapsulation method for multi-media environments as described in the first aspect of the present invention.

[0056] The beneficial effects of this invention are:

[0057] 1. Multi-environment adaptability

[0058] Through dynamic impedance matching and environmental perception feedback mechanisms, the system can detect the dielectric properties of media such as metals and liquids in real time, and dynamically adjust the operating frequency band and impedance matching parameters using particle swarm optimization algorithms, thereby improving the energy transmission efficiency of the tag in complex media environments by more than 40% and increasing the reading distance stability to within ±5%.

[0059] The multi-band reconfigurable antenna array (covering 860 MHz–2.45 GHz) combined with a serpentine folded dipole structure effectively suppresses surface wave interference, achieving a radiation efficiency of over 75% (compared to <50% for traditional labels).

[0060] 2. High-reliability packaging design

[0061] The gradient dielectric material layer achieves a smooth transition of electromagnetic field energy from the substrate to the environment through the gradient distribution of dielectric constant, reducing the reflection loss at the dielectric interface (reflection coefficient ≤ -20 dB).

[0062] The electromagnetic shielding isolation layer, combined with the silver-plated nylon mesh structure, attenuates environmental coupling interference by more than 30 dB while maintaining an opening ratio of more than 85%, ensuring that the label is flexible and bendable (curvature radius ≤ 5 mm).

[0063] 3. Intelligent and low-power characteristics

[0064] The multi-label collision protocol based on dynamic weighted fusion algorithm improves recognition efficiency by 60% and reduces the false reading rate to less than 0.1% in densely deployed scenarios (>200 labels / ㎡).

[0065] The self-healing protective coating can repair more than 80% of micro-cracks within 24 hours. Combined with a temperature compensation circuit, it allows the label to withstand temperatures as low as -40°C. Up to 85 Lifespan extended to more than 5 years in extreme environments.

[0066] 4. Low cost and easy deployment

[0067] The flexible polyimide substrate supports roll-to-roll printing processes, reducing the cost of manufacturing a single label by 30%, making it suitable for large-scale industrial applications.

[0068] Overall Results: This solution overcomes the technical bottlenecks of impedance mismatch, frequency band rigidity, and poor packaging reliability of RFID tags in multi-media environments. In complex industrial scenarios (such as metal pipeline monitoring and liquid medicine traceability), the average recognition rate has been increased from 65% in traditional solutions to over 98%, providing a highly robust and low-power radio frequency identification solution for the IoT sensing layer. Attached Figure Description

[0069] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. 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.

[0070] Figure 1This is a schematic diagram of the RFID tag adaptive separation system for multi-media environments in Example 1;

[0071] Figure 2 This is a flowchart of the RFID tag encapsulation method for multi-media environments in Example 2. Detailed Implementation

[0072] 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.

[0073] 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.

[0074] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0075] Example 1, referring to Figure 1 This is the first embodiment of the present invention, which provides an adaptive RFID tag separation system for multi-media environments, comprising:

[0076] The multi-band reconfigurable antenna array 101 consists of N radiating elements, and its resonant frequency satisfies:

[0077]

[0078] in, The length of the nth radiating element. where c is the equivalent dielectric constant and c is the speed of light.

[0079] The embedded environment sensing module 102 is used to detect the dielectric constant of the medium in which the tag is located. and loss factor Its output parameters satisfy:

[0080]

[0081] in, This is the measured capacitance. Where A is the dielectric thickness, A is the electrode area, and G is the conductivity. Angular frequency;

[0082] The adaptive impedance tuning circuit 103 adjusts the antenna input impedance in real time through a varactor diode array. To make it compatible with the chip impedance Matching, satisfying:

[0083]

[0084] in, Let be the conjugate complex number of the chip impedance. This is the equivalent resistance of the chip. This is the equivalent reactance of the chip;

[0085] The intelligent control unit 104, based on data from the embedded environment perception module 102, dynamically selects the optimal operating frequency band and impedance matching parameters through a particle swarm optimization algorithm.

[0086] The multi-band reconfigurable antenna array 101 adopts a serpentine folded dipole structure with a spacing between adjacent radiating elements. satisfy:

[0087]

[0088] in, Where N is the minimum operating frequency of the system, and N is the number of radiating elements. The maximum wavelength corresponds to the lowest operating frequency supported by the system, and c is the speed of light.

[0089] The embedded environment sensing module 102 integrates a temperature compensation circuit, and its dielectric constant correction formula is as follows:

[0090]

[0091] Where T is the ambient temperature. For reference temperature, = is the temperature coefficient of the dielectric constant.

[0092] The adaptive impedance tuning circuit 103 includes a π-type matching network, whose matching parameters are determined by the following formula:

[0093]

[0094] in, This is the antenna's equivalent resistance. This is the chip's equivalent resistance. This is the equivalent reactance of the chip. Where ω is the angular frequency, L is the inductance value in the matching network, and C is the capacitance value in the matching network.

[0095] The intelligent control unit 104 adopts a dynamic weighted fusion algorithm, and its objective function is:

[0096]

[0097] in, For received power, Antenna quality factor, Power threshold, This represents the minimum antenna quality factor required by the system. It is a dynamic weighting factor used to balance the optimized weights between received power and antenna quality factor.

[0098] The system supports a multi-label collision avoidance protocol with a random backoff time. satisfy:

[0099]

[0100] Where retry represents the number of retries, and BW represents the channel bandwidth. This represents the maximum received signal strength value among all tag signals detected in the current communication scenario. This represents the signal strength value detected by the reader for a specific tag in the most recent communication.

[0101] Example 2, refer to Figure 2 This is the second embodiment of the present invention, which provides an RFID tag encapsulation method for multi-media environments, including the following steps:

[0102] S1. An antenna radiating element is printed on a flexible polyimide substrate 201, where the substrate thickness t1 satisfies...

[0103]

[0104] in, The dielectric constant of the substrate is 1. The free-space wavelength of the antenna at the target's operating frequency;

[0105] Step S1 is the process of printing antenna radiating elements on a flexible substrate, and its specific implementation is as follows:

[0106] 1. Flexible substrate selection and thickness design

[0107] Material selection:

[0108] Polyimide (PI) is used as the flexible substrate, and its characteristics are as follows:

[0109] Dielectric constant ε sub =3.5±0.2 (tested at 1 MHz);

[0110] Loss factor tanδ≤0.002;

[0111] The coefficient of thermal expansion (CTE) is 15-20 ppm / °C, ensuring dimensional stability under high-temperature processes.

[0112] Thickness calculation:

[0113] The substrate thickness is determined based on the formula and the target operating frequency:

[0114] Example: If the operating frequency =915MHz, then:

[0115]

[0116] The maximum thickness of the substrate is:

[0117]

[0118] Preferred range: Actual selection =25−100 μm, to balance flexibility and mechanical strength (such as DuPont).

[0119] Kapton® HN type film, nominal thickness 50 μm.

[0120] 2. Antenna radiating element printing process

[0121] Conductive materials:

[0122] Using nano silver paste (conductivity σ≥5×10) 6 S / m) or copper-based conductive ink (sheet resistance ≤50mΩ after curing), achieved through the following process:

[0123] Substrate pretreatment: plasma cleaning (100 W power, 30 s time) to improve surface adhesion;

[0124] Graphic printing: High-precision screen printing (300-400 mesh) or inkjet printing (5-10 pL droplet volume) is used to form a serpentine folded dipole structure.

[0125] Thermosetting: Stepped temperature increase (80) Preheat for 5 minutes → 150°C (Cure for 20 minutes) to ensure the resistivity of the conductive layer is stable.

[0126] Antenna structural parameters:

[0127] Number of serpentine bend cycles: 4-6;

[0128] Line width / spacing: 0.3 mm / 0.2 mm (for 915 MHz band);

[0129] Total length matches half the wavelength of the target frequency band:

[0130]

[0131] 3. Electromagnetic performance verification and optimization

[0132] Simulation verification: Using HFSS or CST three-dimensional electromagnetic field simulation software, optimize the antenna radiation pattern and input impedance; set the substrate dielectric constant. =3.5, loss factor tanδ=0.002; load a metal backplate to simulate a metal environment, and adjust the serpentine bending angle (45°). 60 To suppress surface waves; ensure return loss

[0133] S 11 ≤−15 dB (within the target frequency band).

[0134] Actual calibration: The antenna impedance was measured using a vector network analyzer (VNA) to verify its correlation with the chip impedance Z. chip =30−j200 Ω conjugate matching (Z in =30+j200 Ω).

[0135] 4. Example

[0136] Example 1:

[0137] Substrate: Kapton® HN film, =50μm;

[0138] Antenna: serpentine dipole, total length L=82mm, line width 0.3mm;

[0139] Performance: At 915 MHz, the measured gain is 2.1 dBi and the reading distance (metal surface) is 1.2 m.

[0140] Example 2:

[0141] Substrate: Liquid crystal polymer (LCP). =75μm, =2.9 Antenna: Dual-band structure (860 MHz / 2.45 GHz), line width 0.2 mm / 0.1 mm;

[0142] Performance: Dual-frequency return loss ≤-18 dB, readout rate ≥95% in liquid environments.

[0143] It should be noted that the substrate thickness is ≤100μm, which can fit curved surfaces with a radius of ≤5 mm; the serpentine structure effectively reduces the antenna size and supports UHF to microwave frequency bands; it is suitable for roll-to-roll (R2R) mass production, and the manufacturing cost per tag is ≤0.15 yuan.

[0144] S2. A gradient dielectric material layer 202 is applied, the dielectric constant of which is distributed exponentially along the thickness direction:

[0145]

[0146] Where k is the attenuation coefficient, The total thickness of the gradient layer, It is the minimum dielectric constant;

[0147] The gradient dielectric layer (202) is composed of barium strontium titanate (BST) and polytetrafluoroethylene (PTFE) in a volume ratio of V BST :V PTFE =(1:9)∼(4:6) composite, its dielectric constant adjustment range is 2.1≤ ≤120.

[0148] Step S2 is the design and fabrication process of the gradient dielectric material layer, and its specific implementation is as follows:

[0149] 1. Selection and Formulation Design of Gradient Dielectric Materials

[0150] Material composition: A composite material of barium strontium titanate (BaSrTiO3, BST) and polytetrafluoroethylene (PTFE) is used, and the dielectric constant is controlled by the volume ratio.

[0151] BST volume ratio: V BST :V PTFE =1:9~4:6, corresponding to the dielectric constant range =2.1~120 (tested at 1 MHz);

[0152] Functional allocation:

[0153] BST: High dielectric constant component, improving near-field coupling efficiency;

[0154] PTFE: Low-loss flexible matrix, reducing dielectric loss (tanδ≤0.001).

[0155] Gradient distribution implementation:

[0156] By using a layered coating process, the dielectric constant is distributed exponentially along the thickness direction (z-axis):

[0157]

[0158] Parameter settings:

[0159] Initial value: =2.1 (surface layer, close to the environment);

[0160] Termination value: = (Bottom layer, near the antenna);

[0161] Attenuation coefficient: Typical value .

[0162] 2. Gradient layer fabrication process

[0163] Process flow:

[0164] Slurry preparation: BST nanoparticles (particle size 50-100 nm) and PTFE emulsion (solid content 60%) are mixed at the target volume ratio and ultrasonically dispersed for 30 min to form a homogeneous slurry;

[0165] Layer-by-layer coating:

[0166] Using precision spraying equipment, layers are sprayed onto the flexible substrate (the antenna layer prepared by S1), with each layer having a thickness of [missing information].

[0167] Δz = 5 − 10 μm;

[0168] The volume ratio of BST increases with each layer (e.g., from 10% to 40%), and a total of 10-20 layers are applied.

[0169] Gradient curing:

[0170] Stepped temperature rise: 80°C pre-curing for 10 min → 180°C hot pressing (pressure 0.5 MPa, time 30 min) to eliminate interlayer interfaces;

[0171] UV post-curing (wavelength 365 nm, intensity 100 mW / cm², time 5 min) enhances interlayer bonding.

[0172] Thickness control:

[0173] Total thickness Based on the operating frequency design, the typical value is:

[0174]

[0175] in, The average dielectric constant of the gradient dielectric layer; The free-space wavelength corresponding to the target operating frequency of the tag; Example: If =32.8cm, =30, then ≈1.8mm.

[0176] 3. Electromagnetic performance optimization and verification

[0177] Simulation modeling:

[0178] Create a gradient dielectric layer model in CST Microwave Studio and set the exponential distribution parameters. ;

[0179] Apply boundary conditions to a metallic or liquid environment and optimize the gradient parameters to make the reflection coefficient Γ ≤ −20dB;

[0180] Verify improved energy transfer efficiency:

[0181]

[0182] The radio frequency power incident on the tag antenna, This represents the actual power received by the tag chip. For energy transfer efficiency.

[0183] Actual test verification:

[0184] Dielectric constant testing: Impedance analysis was performed on each layer using an impedance analyzer (such as the Agilent 4294A). Values ​​are set to ensure that the gradient distribution error is ≤5%;

[0185] Reflection Loss Test: Vector Network Analyzer (VNA) Measurement of Antenna Port ≤−18dB (860-960 MHz band);

[0186] Environmental adaptability testing:

[0187] Metal surfaces: Reading distance ≥1.5 m (traditional solution ≤0.8 m);

[0188] Liquid containers: Recognition rate ≥98% (glycerol solution, =50).

[0189] 4. Example

[0190] Example 1:

[0191] Gradient parameter: k = 0.1 μm−1, =1.5mm, =2.1, =50;

[0192] Performance: Energy transfer efficiency η = 68% in a metallic environment, and S11 = −21dB in a liquid environment.

[0193] Example 2:

[0194] Gradient parameter: k = 0.15 μm−1, =2.0mm, =2.1, =80;

[0195] Performance: Reading distance fluctuation ≤ ±3% in heterogeneous media (metal + plastic) environments.

[0196] It should be noted that the gradient dielectric layer effectively reduces the reflection loss at the dielectric interface (≤-20 dB) and improves the energy transmission efficiency by ≥20%; the exponential distribution design supports the UHF to microwave frequency bands (400 MHz-5.8 GHz); it is suitable for roll-to-roll (R2R) continuous coating with a production efficiency of ≥5000 pieces / hour.

[0197] S3. An electromagnetic shielding isolation layer 203 is added, whose surface impedance satisfy:

[0198]

[0199] in, For the intrinsic impedance of free space, The electrical conductivity of the shielding material;

[0200] The electromagnetic shielding layer (203) is a silver-plated nylon mesh with a mesh aperture of [missing information]. satisfy:

[0201]

[0202] Step S3 is the design and fabrication process of the electromagnetic shielding isolation layer, and its specific implementation method is as follows:

[0203] 1. Shielding material selection and structural design

[0204] Material selection:

[0205] The shielding layer uses silver-plated nylon mesh as its core material, and its characteristics are as follows:

[0206] Surface impedance: ≥5 =5×377 Ω=1885 Ω, high impedance characteristics are achieved through mesh aperture design;

[0207] Electrical conductivity: ≥105S / m, guaranteed by the thickness of the silver plating layer (≥2 μm);

[0208] Flexible compatibility: The nylon substrate (thickness 50-100 μm) ensures that the shielding layer can be bent (radius of curvature ≤ 5 mm).

[0209] Mesh parameter design:

[0210] Mesh aperture satisfy

[0211]

[0212] Example: If =32.8cm (915 MHz), then ≤3.28cm, actual aperture selected is 2.5 cm;

[0213] Opening ratio calculation: Opening ratio = , where line width =0.5 mm, opening ratio 86%.

[0214] 2. Shielding layer fabrication process

[0215] Process flow:

[0216] Substrate pretreatment: The nylon mesh (200 mesh) was plasma cleaned (Ar gas, power 150 W, time 5 min) to improve the adhesion of the coating;

[0217] Magnetron sputtering silver plating:

[0218] Vacuum degree: 5×10 -3 Pa;

[0219] Sputtering power: 300 W, coating thickness 2-3 ;

[0220] Sheet resistance after plating: ≤0.1Ω.

[0221] Hot-pressing composite: The silver-plated mesh and the gradient dielectric layer (prepared by S2) are bonded together by a hot-pressing process (temperature 120°C). The layers are composited at a pressure of 0.3 MPa for 10 minutes to ensure no air bubbles between layers.

[0222] Edge insulation treatment: Apply UV-cured insulating adhesive (50mm thick) ), to prevent edge leakage.

[0223] Key parameter control:

[0224] Skin-to-skin depth verification:

[0225] (For example, at 915 MHz, m)

[0226] The silver plating layer thickness is ≥2 μm to ensure that the transmission loss under the skin effect is ≤0.5 dB.

[0227] 3. Shielding effectiveness verification and optimization

[0228] Test method:

[0229] Shielding effectiveness (SE) test:

[0230] According to the standard IEEE 299, a vector network analyzer (VNA) was used to measure the signal attenuation before and after shielding;

[0231] Target: SE ≥ 30 dB (30 MHz-3 GHz band).

[0232] Flexibility test:

[0233] With a bending radius of 5 mm, after 1000 cyclic bending cycles, the conductivity decreases by ≤5%.

[0234] Environmental tolerance:

[0235] High temperature and high humidity (85 After 500 h at 85% RH, the sheet resistance change is ≤10%.

[0236] Example:

[0237] Example 1:

[0238] The silver plating layer is 2.5 μm thick, and the mesh aperture is 2.5 cm.

[0239] The measured SE was 35 dB (915 MHz), and the SE remained ≥33 dB after bending.

[0240] Example 2:

[0241] The silver plating layer is 3 μm thick and the mesh aperture is 1.8 cm (suitable for 2.45 GHz).

[0242] With a measured SE of 40 dB and a weight of only 15 g / m², it is suitable for lightweight labels.

[0243] It should be noted that this invention has the advantages of high-efficiency electromagnetic isolation, ultra-thin flexible structure and low-cost mass production. Through high-impedance grid design, the eddy current loss on the metal surface is reduced to ≤10%, and the coupling interference attenuation in liquid environment is ≥25 dB; the total thickness is ≤150μm, which can fit complex curved surfaces (such as pipes and bottles); the magnetron sputtering process supports roll-to-roll production, and the cost per layer is ≤0.8 yuan / ㎡.

[0244] S4. Apply a self-healing protective coating 204, the thickness of which is... With dielectric loss satisfy:

[0245] .

[0246] The self-healing protective coating (204) contains microencapsulated siloxane material with a rupture threshold pressure. satisfy:

[0247]

[0248] in, denoted as the microcapsule radius.

[0249] Step S4 is the design and preparation process of the self-healing protective coating, and its specific implementation method is as follows:

[0250] 1. Selection and formulation design of self-healing materials

[0251] Material composition:

[0252] Microencapsulated siloxane is used as the self-healing functional component, and its core parameters are as follows:

[0253] Microcapsule size: diameter =10−50μm, shell thickness =1−3μm (polyurea material);

[0254] Repair agent content: siloxane mass percentage ≥60%, microcapsule volume fraction 10%-15%;

[0255] Triggering mechanism: Mechanical stress (fracture threshold) The release of the repair agent is triggered by temperature (>50°C).

[0256] Substrate material:

[0257] Polyurethane (PU) or epoxy resin is selected as the coating matrix, and its properties meet the following requirements:

[0258] Dielectric loss: ≤0.005 (1 MHz);

[0259] Flexibility: Elongation at break ≥200% (ASTM D638 standard).

[0260] 2. Coating Preparation Process

[0261] Process flow:

[0262] (1) Microcapsule dispersion: Siloxane microcapsules and PU prepolymer were mixed at a mass ratio of 1:9 and ultrasonically dispersed (40kHz, 30 min) to ensure uniform distribution;

[0263] (2) Coating process:

[0264] Spraying: Using a high-pressure airless spraying device (nozzle diameter 0.3 mm), a uniform coating is formed on the surface of the shielding layer (prepared by S3), with a wet film thickness of 100-150 μm;

[0265] Curing: Stepped curing (60) Pre-curing for 1 hour → 120 (Final curing 2 hours) to form a cross-linked network;

[0266] (3) Thickness control: According to the formula Calculate the maximum allowable thickness:

[0267] Example: If =32.8cm, =0.004, then 0.328 / 0.004 0.82mm, actual selection =50μm.

[0268] 3. Self-healing performance verification

[0269] Rupture threshold test:

[0270] Coating fracture threshold measured using nanoindentation. Verification formula

[0271]

[0272] Example: If =1.5 GPa, microcapsule radius =20 μm, then:

[0273]

[0274] Repair efficiency test:

[0275] Scratch repair: Create scratches 50 μm deep using a blade, 25 Observe the repair progress within the next 24 hours (using an optical microscope);

[0276] Electrical performance recovery: Measure the change in tag reading distance before and after repair (target: recovery rate ≥80%).

[0277] Environmental durability:

[0278] High temperature and high humidity (85 After 85% RH, 500 h, the repair efficiency is ≥70%;

[0279] Hot and cold cycle (-40) ↔85 After 100 cycles, the coating showed no delamination.

[0280] 4. Example

[0281] Example 1:

[0282] Coating parameters: =50μm, microcapsule volume fraction 12%;

[0283] Performance: Scratches (50 μm) were 85% repaired within 18 hours, and the reading distance was restored from 1.2 m to 1.0 m;

[0284] Example 2:

[0285] Coating parameters: =80μm, microcapsule volume fraction 15%;

[0286] Performance: After 100 bending cycles (curvature radius 5 mm), the coating showed no cracks and the dielectric loss remained at tanδ=0.0038.

[0287] It should be noted that this invention has the advantages of dynamic repair capability, electrical compatibility, and environmental robustness. After the microcapsules rupture, the siloxane filling rate is ≥90%, and the repair response time is ≤24 h (25). Ultra-low dielectric loss (tanδ≤0.005) ensures that the coating affects RFID signals by ≤3%; and it passes a 5-year accelerated aging test (IEC 60068-2 standard) with performance degradation of ≤10%.

[0288] This embodiment also provides a computer device applicable to the RFID tag encapsulation method for multi-media environments, including: a memory and a processor; the memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions to implement the RFID tag encapsulation method for multi-media environments as proposed in the above embodiment.

[0289] The computer device can be a terminal, comprising a processor, memory, communication interface, display screen, and input devices connected via a system bus. The processor provides computing and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs stored in the non-volatile storage media. The communication interface is used for wired or wireless communication with external terminals; wireless communication can be achieved through Wi-Fi, carrier networks, NFC (Near Field Communication), or other technologies. The display screen can be an LCD screen or an e-ink screen. The input devices can be a touch layer covering the display screen, buttons, a trackball, or a touchpad on the computer device's casing, or an external keyboard, touchpad, or mouse.

[0290] This embodiment also provides a storage medium storing a computer program, which, when executed by a processor, implements the RFID tag encapsulation method for multi-media environments as proposed in the above embodiments. The storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as Static Random Access Memory (SRAM), Electrically Erasable Programmable Read-Only Memory (EEPROM), Erasable Programmable Read Only Memory (EPROM), Programmable Red-Only Memory (PROM), Read-Only Memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk.

[0291] In summary, this invention, through dynamic impedance matching and environmental sensing feedback mechanisms, enables the system to detect the dielectric properties of media such as metals and liquids in real time. It also utilizes a particle swarm optimization algorithm to dynamically adjust the operating frequency band and impedance matching parameters, improving the tag's energy transmission efficiency by over 40% in complex media environments and increasing read distance stability to within ±5%. A multi-band reconfigurable antenna array (covering 860 MHz–2.45 GHz) combined with a serpentine folded dipole structure effectively suppresses surface wave interference, achieving a radiation efficiency of over 75% (compared to <50% for traditional tags). A gradient dielectric material layer, through its gradient dielectric constant distribution, achieves a smooth transition of electromagnetic field energy from the substrate to the environment, reducing interface reflection loss (reflection coefficient ≤ -20 dB). An electromagnetic shielding isolation layer, combined with a silver-plated nylon mesh structure, attenuates environmental coupling interference by over 30 dB while maintaining an aperture ratio of over 85%, ensuring the tag's flexibility and bendability (radius of curvature ≤ 5 mm). A multi-tag collision protocol based on a dynamic weighted fusion algorithm improves recognition efficiency by 60% and reduces the false read rate to less than 0.1% in densely deployed scenarios (>200 tags / ㎡). The self-healing protective coating can repair more than 80% of micro-cracks within 24 hours. Combined with a temperature compensation circuit, the tags can withstand temperatures as low as -40°C. Up to 85 Lifespan extended to over 5 years in extreme environments. The flexible polyimide substrate supports roll-to-roll printing, reducing single-tag manufacturing costs by 30%, making it suitable for large-scale industrial applications. This solution overcomes the technical bottlenecks of impedance mismatch, frequency band rigidity, and poor packaging reliability in multi-media environments. In complex industrial scenarios (such as metal pipeline monitoring and liquid pharmaceutical traceability), the average recognition rate is increased from 65% in traditional solutions to over 98%, providing a highly robust and low-power RFID solution for the IoT sensing layer.

[0292] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. An adaptive RFID tag separation system for multi-media environments, characterized in that, include: A multi-band reconfigurable antenna array (101) consists of N radiating elements, whose resonant frequencies satisfy: in, The length of the nth radiating element. where c is the equivalent dielectric constant and c is the speed of light. The embedded environment sensing module (102) is used to detect the dielectric constant of the medium in which the tag is located. and loss factor Its output parameters satisfy: in, This is the measured capacitance. Where A is the dielectric thickness, A is the electrode area, and G is the conductivity. Angular frequency; The adaptive impedance tuning circuit (103) adjusts the antenna input impedance in real time through a varactor diode array. To make it compatible with the chip impedance Matching, satisfying: in, Let be the conjugate complex number of the chip impedance. This is the equivalent resistance of the chip. Here, j represents the chip's equivalent reactance, and j is the imaginary unit. The intelligent control unit (104) dynamically selects the optimal operating frequency band and impedance matching parameters based on the data from the embedded environment perception module (102) using the particle swarm optimization algorithm.

2. The RFID tag adaptive separation system for multi-media environments as described in claim 1, characterized in that, The multi-band reconfigurable antenna array (101) adopts a serpentine folded dipole structure, with the spacing between adjacent radiating elements... satisfy: in, Where N is the minimum operating frequency of the system, and N is the number of radiating elements. The maximum wavelength corresponds to the lowest operating frequency supported by the system, and c is the speed of light.

3. The RFID tag adaptive separation system for multi-media environments as described in claim 1, characterized in that, The embedded environment sensing module (102) integrates a temperature compensation circuit, and its dielectric constant correction formula is as follows: Where T is the ambient temperature. For reference temperature, = The temperature coefficient of dielectric constant is the original dielectric constant.

4. The RFID tag adaptive separation system for multi-media environments as described in claim 1, characterized in that, The adaptive impedance tuning circuit (103) includes a π-type matching network, whose matching parameters are determined by the following formula: in, This is the antenna's equivalent resistance. This is the chip's equivalent resistance. This is the equivalent reactance of the chip. Where ω is the angular frequency, L is the inductance value in the matching network, and C is the capacitance value in the matching network.

5. The RFID tag adaptive separation system for multi-media environments as described in claim 1, characterized in that, The intelligent control unit (104) adopts a dynamic weighted fusion algorithm, and its objective function is: in, For received power, Antenna quality factor, Power threshold, This represents the minimum antenna quality factor required by the system. It is a dynamic weighting factor used to balance the optimized weights between received power and antenna quality factor.

6. The RFID tag adaptive separation system for multi-media environments as described in claim 1, characterized in that, The system supports a multi-label collision avoidance protocol with a random backoff time. satisfy: Where retry represents the number of retries, and BW represents the channel bandwidth. This represents the maximum received signal strength value among all tag signals detected in the current communication scenario. This represents the signal strength value detected by the reader for a specific tag in the most recent communication.

7. A method for encapsulating RFID tags in multi-media environments, implemented based on the adaptive RFID tag separation system for multi-media environments as described in any one of claims 1 to 6, characterized in that, Includes the following steps: S1. An antenna radiating element is printed on a flexible polyimide substrate (201), wherein the substrate thickness t1 satisfies in, The dielectric constant of the substrate is 1. The free-space wavelength of the antenna at the target's operating frequency; S2. A gradient dielectric material layer (202) is covered, the dielectric constant of which is distributed exponentially along the thickness direction: Where k is the attenuation coefficient, The total thickness of the gradient layer, It is the minimum dielectric constant. Let z be the relative permittivity at position z, e be the base of the natural logarithm, and z be the distance variable along the thickness direction of the gradient dielectric material layer. S3. An electromagnetic shielding isolation layer (203) is added, whose surface impedance is... satisfy: in, For the intrinsic impedance of free space, The electrical conductivity of the shielding material; S4. Apply a self-healing protective coating (204) of thickness. With dielectric loss satisfy: 。 8. The RFID tag encapsulation method for multi-media environments as described in claim 7, characterized in that, The gradient dielectric material layer (202) is composed of barium strontium titanate (BST) and polytetrafluoroethylene (PTFE) in a volume ratio of V BST :V PTFE =(1:9)∼(4:6) composite, its dielectric constant adjustment range is 2.1≤ ≤120.

9. The RFID tag encapsulation method for multi-media environments as described in claim 7, characterized in that, The electromagnetic shielding isolation layer (203) is a silver-plated nylon mesh with a mesh aperture of [missing information]. satisfy:

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