Multi-medium environment-oriented RFID tag adaptive separation system and packaging method

Abstract

The invention discloses a multi-medium environment-oriented RFID (Radio Frequency Identification) tag adaptive separation system and packaging method, and belongs to the technical field of radio frequency identification. The system is composed of a multi-band reconfigurable antenna array, an embedded environment sensing module, a self-adaptive impedance tuning circuit and an intelligent control unit, the working frequency and the impedance matching state are dynamically adjusted by detecting dielectric constants and electromagnetic loss parameters in real time, and optimal energy transmission in the multi-medium environment is achieved. According to the packaging method, a multi-layer composite structure design is adopted, a flexible substrate and a gradient dielectric material are combined, an antenna radiation pattern is simulated and optimized through a three-dimensional electromagnetic field, and an electromagnetic shielding isolation layer is introduced to reduce environmental coupling interference. According to the scheme, the tag recognition rate and the communication distance in a complex medium scene are effectively improved, meanwhile, the tag has the characteristics of self-repairing of a protective coating and low power consumption, and the tag can be widely applied to the fields of industrial Internet of Things, intelligent logistics and special environment monitoring.

Description

Technical Field

[0001] The present invention relates to the field of radio frequency identification technology, in particular to an RFID tag adaptive separation system and packaging method for a multi-media environment. Background Art

[0002] Radio Frequency Identification (RFID) technology, as a core component of the IoT's perception layer, has been widely used in fields such as logistics tracking, asset management, and industrial automation. However, traditional RFID tags suffer from severe signal attenuation and reading stability in multi-media environments composed of metal, liquid, and heterogeneous materials due to electromagnetic wave reflection, dielectric loss, and impedance mismatch. Existing technologies primarily mitigate environmental interference by optimizing antenna structures (such as adding isolation layers or using flexible substrates) or selecting high-dielectric materials. However, these methods generally suffer from fixed frequency bands, poor adaptability, and high manufacturing costs, making them difficult to meet the dynamic needs of complex scenarios.

[0003] A Chinese invention patent discloses a "metal-resistant RFID tag and its preparation method", which uses a multi-layer ceramic dielectric substrate and an annular slot antenna design to improve the substrate dielectric constant (ε r ≥10) to reduce eddy current loss on metal surfaces. However, this solution 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 ambient medium; (2) The reliance on a high dielectric constant substrate increases the thickness of the tag (>2mm), making it difficult to adhere to curved metal surfaces; (3) The electromagnetic coupling effect in the liquid environment is not considered, resulting in a reading distance fluctuation of more than 40% in mixed media scenarios. The above problems show that static designs that rely solely on structural optimization are difficult to meet the dynamic adaptation requirements in a multi-media environment.

[0004] Based on the analysis of existing technologies, the technical bottlenecks of current 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 offsets between the antenna impedance and the chip impedance, and traditional matching networks cannot respond quickly; (2) Poor frequency band coverage and radiation pattern adaptability: Fixed frequency band designs are susceptible to interference in complex electromagnetic environments, and radiation patterns are difficult to optimize adaptively; (3) Low environmental compatibility of packaging structures: Existing packaging materials are sensitive to temperature, humidity, and mechanical stress, and lack gradient dielectric and self-healing protection capabilities. These problems have severely restricted the in-depth application of RFID technology in fields such as the Industrial Internet of Things and special monitoring. A comprehensive solution integrating environmental perception, dynamic tuning, and intelligent packaging is urgently needed. Summary of the Invention

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

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

[0007] In order to solve the above technical problems, the present invention provides the following technical solutions:

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

[0009] The multi-band reconfigurable antenna array consists of N radiating elements, whose resonant frequencies satisfy:

[0010]

[0011] Among them, L n is the length of the nth radiation unit, ε eff is the equivalent dielectric constant, c is the speed of light;

[0012] Embedded environmental sensing module, used to detect the dielectric constant ε of the medium in which the tag is located r And loss factor tanδ, its output parameters satisfy:

[0013]

[0014] Among them, C meas is the measured capacitance, d is the dielectric thickness, ε0 is the angular frequency, A is the electrode area, G is the conductivity, and ω is the angular frequency;

[0015] Adaptive impedance tuning circuit, real-time adjustment of antenna input impedance Z through varactor diode array in , so that it is consistent with the chip impedance Z chip Match, satisfy:

[0016]

[0017] in, is the conjugate complex number of the chip impedance, R chip is the equivalent resistance of the chip, X chip is the equivalent reactance of the chip;

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

[0019] As a preferred solution of the RFID tag adaptive separation system for a multi-media environment of the present invention, the multi-band reconfigurable antenna array adopts a serpentine folded dipole structure, and the spacing ΔL between adjacent radiating elements satisfies:

[0020]

[0021] Among them, f min is the lowest operating frequency of the system, N is the number of radiation units, λ max is the maximum wavelength corresponding to the lowest operating frequency supported by the system, and c is the speed of light.

[0022] As a preferred solution of the RFID tag adaptive separation system for a multi-media environment of the present invention, the embedded environment sensing module integrates a temperature compensation circuit, and its dielectric constant correction formula is:

[0023] ε' r =ε r [1+γ(T-T0)], γ=-0.0025 / °C, where T is the ambient temperature, T0 is the reference temperature, T0=25°C, and γ is the temperature coefficient of the dielectric constant.

[0024] As a preferred solution of the RFID tag adaptive separation system for a multi-media environment of the present invention, the adaptive impedance tuning circuit includes a π-type matching network, and its matching parameters are determined by the following formula:

[0025]

[0026] Among them, R ant is the antenna equivalent resistance, R chip is the chip equivalent resistance, X chip is the equivalent reactance of the chip, ω is the angular frequency, L is the inductance value in the matching network, and C is the capacitance value in the matching network.

[0027] As a preferred solution of the RFID tag adaptive separation system for a multi-media environment described in the present invention, the intelligent control unit adopts a dynamic weighted fusion algorithm, and its objective function is:

[0028]

[0029] Among them, P received is the received power, Q factor is the antenna quality factor, P threshold is the power threshold, Q min is the minimum antenna quality factor required by the system, and α and β are dynamic weighting factors used to balance the optimization weight between the received power and the antenna quality factor.

[0030] As a preferred solution of the RFID tag adaptive separation system for multi-media environment of the present invention, the system supports multi-tag collision avoidance protocol with random backoff time t backoff satisfy:

[0031]

[0032] Among them, retry is the number of retries, BW is the channel bandwidth, RSSI max RSSI is the maximum received signal strength value among all tag signals detected in the current communication scenario. current It is the signal strength value of a specific tag detected by the reader in the most recent communication.

[0033] As a preferred solution of the RFID tag packaging method for a multimedia environment of the present invention, the method includes the following steps:

[0034] S1. Print the antenna radiation unit on the flexible polyimide substrate, and the substrate thickness t1 satisfies

[0035]

[0036] Among them, ε sub is the substrate dielectric constant, λ operate is the free space wavelength of the antenna at the target operating frequency; S2 is a layer of gradient dielectric material, whose dielectric constant is exponentially distributed along the thickness direction:

[0037] ε r (z)=ε min ·e kz ,0≤z≤t2

[0038] Where k is the attenuation coefficient, t2 is the total thickness of the gradient layer, ε min is the minimum dielectric constant;

[0039] S3. Add an electromagnetic shielding isolation layer, whose surface impedance Z shield satisfy:

[0040] Z shield ≥5Z0 and σ shield ≥10 5 S / m

[0041] Where Z0 is the intrinsic impedance of free space, σ shield is the conductivity of the shielding material;

[0042] S4. Apply self-repairing protective coating, its thickness t3 and dielectric loss δ coating satisfy:

[0043] t3·tanδ coating ≤0.01λ operate .

[0044] As a preferred solution of the RFID tag packaging method for a multi-media environment of the present invention, wherein: the gradient dielectric material layer is composed of barium strontium titanate (BST) and polytetrafluoroethylene (PTFE) in a volume ratio of V BST :V PTFE =(1:9)~(4:6) composite, the dielectric constant adjustment range is 2.1≤ε r ≤120.

[0045] As a preferred solution of the RFID tag packaging method for a multi-media environment of the present invention, wherein: the electromagnetic shielding isolation layer is a silver-plated nylon mesh with a mesh aperture d mesh satisfy:

[0046] And the opening rate is ≥85%.

[0047] As a preferred solution of the RFID tag packaging method for a multimedia environment of the present invention, the self-repairing protective coating comprises a microencapsulated silicone material, and its rupture threshold pressure P rupture satisfy:

[0048] P rupture ≥2σ coating / r capsule

[0049] Among them, σ coating is the Young's modulus of the coating, r capsule is the microcapsule radius.

[0050] In a second aspect, the present invention provides a computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: when the computer program is executed by the processor, any step of the RFID tag packaging method for a multimedia environment as described in the first aspect of the present invention is implemented.

[0051] In a third aspect, 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, any step of the RFID tag packaging method for a multimedia environment as described in the first aspect of the present invention is implemented.

[0052] The beneficial effects of the present invention are:

[0053] 1. Multi-environment adaptability

[0054] 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 use the particle swarm optimization algorithm to dynamically adjust the operating frequency band and impedance matching parameters, thereby increasing the energy transmission efficiency of the tag in complex media environments by more than 40% and improving the reading distance stability to within ±5%.

[0055] The multi-band reconfigurable antenna array (covering the frequency band of 860MHz–2.45GHz) combined with the serpentine folded dipole structure effectively suppresses surface wave interference and achieves a radiation efficiency of over 75% (traditional tags <50%).

[0056] 2. High reliability packaging design

[0057] 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 ≤ -20dB).

[0058] The electromagnetic shielding isolation layer, combined with the silver-plated nylon grid structure, attenuates environmental coupling interference by more than 30dB, while maintaining an opening rate of more than 85%, ensuring that the label is flexible and bendable (curvature radius ≤ 5mm).

[0059] 3.Intelligent and low power consumption features

[0060] The multi-tag collision protocol based on the dynamic weighted fusion algorithm improves recognition efficiency by 60% in dense deployment scenarios (>200 tags / ㎡), with a misreading rate of less than 0.1%.

[0061] The self-healing protective coating can repair more than 80% of microcracks within 24 hours. Combined with the temperature compensation circuit, the life of the tag can be extended to more than 5 years in extreme environments of -40℃ to 85℃.

[0062] 4. Low cost and easy deployment

[0063] The flexible polyimide substrate supports roll-to-roll printing, reducing the manufacturing cost of a single label by 30%, making it suitable for industrial-grade large-scale applications.

[0064] Overall effect: This solution overcomes the technical bottlenecks of RFID tag impedance mismatch, frequency band rigidity and poor packaging reliability in multi-media environments. In complex industrial scenarios (such as metal pipeline monitoring and liquid drug traceability), the average recognition rate is increased from 65% of traditional solutions to over 98%, providing a highly robust, low-power RFID solution for the IoT perception layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0065] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0066] Figure 1 Schematic diagram of the RFID tag adaptive separation system for a multi-media environment in Example 1;

[0067] Figure 2 This is a flow chart of the RFID tag packaging method for a multimedia environment in Example 2. DETAILED DESCRIPTION

[0068] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0069] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0070] Secondly, the term "one embodiment" or "embodiment" 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 various places throughout this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive of other embodiments.

[0071] Example 1, reference Figure 1 , which is the first embodiment of the present invention, provides an RFID tag adaptive separation system for a multi-media environment, comprising:

[0072] The multi-band reconfigurable antenna array 101 is composed of N radiating elements, and its resonant frequency satisfies:

[0073]

[0074] Among them, L n is the length of the nth radiation unit, ε eff is the equivalent dielectric constant, c is the speed of light;

[0075] Embedded environment sensing module 102, used to detect the dielectric constant ε of the medium in which the tag is located r And loss factor tanδ, its output parameters satisfy:

[0076]

[0077] Among them, C meas is the measured capacitance, d is the dielectric thickness, ε0 is the angular frequency, A is the electrode area, G is the conductivity, and ω is the angular frequency;

[0078] Adaptive impedance tuning circuit 103 adjusts the antenna input impedance Z in real time through the varactor diode array in , so that it is consistent with the chip impedance Z chip Match, satisfy:

[0079]

[0080] in, is the conjugate complex number of the chip impedance, R chip is the equivalent resistance of the chip, X chip is the equivalent reactance of the chip;

[0081] The intelligent control unit 104 dynamically selects the optimal operating frequency band and impedance matching parameters based on the data of the embedded environment sensing module 102 through a particle swarm optimization algorithm.

[0082] The multi-band reconfigurable antenna array 101 adopts a serpentine folded dipole structure, and the spacing ΔL between adjacent radiating elements satisfies:

[0083]

[0084] Among them, f min is the lowest operating frequency of the system, N is the number of radiation units, λ max is the maximum wavelength corresponding to the lowest operating frequency supported by the system, and c is the speed of light.

[0085] The embedded environment sensing module 102 integrates a temperature compensation circuit, and its dielectric constant correction formula is:

[0086] ε' r =ε r [1+γ(T-T0)], γ=-0.0025 / °C, where T is the ambient temperature, T0 is the reference temperature, T0=25°C, and γ is the temperature coefficient of the dielectric constant.

[0087] The adaptive impedance tuning circuit 103 includes a π-type matching network, whose matching parameters are determined by the following formula:

[0088]

[0089] Among them, R ant is the antenna equivalent resistance, R chip is the chip equivalent resistance, X chip is the equivalent reactance of the chip, ω is the angular frequency, L is the inductance value in the matching network, and C is the capacitance value in the matching network.

[0090] The intelligent control unit 104 adopts a dynamic weighted fusion algorithm, and its objective function is:

[0091]

[0092] Among them, P received is the received power, Q factor is the antenna quality factor, P thresholdis the power threshold, Q min is the minimum antenna quality factor required by the system, and α and β are dynamic weighting factors used to balance the optimization weight between the received power and the antenna quality factor.

[0093] The system supports multi-tag collision avoidance protocol with random backoff time t backoff satisfy:

[0094]

[0095] Among them, retry is the number of retries, BW is the channel bandwidth, RSSI max RSSI is the maximum received signal strength value among all tag signals detected in the current communication scenario. current It is the signal strength value of a specific tag detected by the reader in the most recent communication.

[0096] Example 2, reference Figure 2 , which is a second embodiment of the present invention, provides an RFID tag packaging method for a multi-media environment, comprising the following steps:

[0097] S1. Printing antenna radiation unit on flexible polyimide substrate 201, substrate thickness t1 satisfies

[0098]

[0099] Among them, ε sub is the substrate dielectric constant, λ operate is the free space wavelength of the antenna at the target operating frequency; Step S1 is the process of printing the antenna radiation unit on the flexible substrate, and its specific implementation is as follows: 1. Flexible substrate selection and thickness design

[0100] Material selection:

[0101] Polyimide (PI) is used as a flexible substrate, and its characteristics are:

[0102] Dielectric constant ε sub =3.5±0.2 (tested at 1MHz);

[0103] Loss factor tanδ≤0.002;

[0104] The coefficient of thermal expansion CTE = 15-20ppm / °C ensures dimensional stability under high temperature processes.

[0105] Thickness calculation:

[0106] Determine the substrate thickness based on the target operating frequency using the formula:

[0107] Example: If the operating frequency f operate=915MHz, then:

[0108]

[0109] The upper limit of substrate thickness is:

[0110]

[0111] Optimal range: t1 = 25-100 μm is actually selected to balance flexibility and mechanical strength (such as DuPont HN type film, nominal thickness 50 μm).

[0112] 2. Antenna radiation unit printing process

[0113] Conductive materials:

[0114] Use nano silver paste (conductivity σ≥5×10 6 S / m) or copper-based conductive ink (square resistance ≤ 50mΩ after curing), achieved through the following process:

[0115] Substrate pretreatment: plasma cleaning (power 100W, time 30s) to improve surface adhesion; graphic printing: high-precision screen printing (screen mesh size 300-400 mesh) or inkjet printing (ink drop volume 5-10pL) is used to form a serpentine folded dipole structure;

[0116] Thermal curing: Stepwise heating (80°C pre-baking for 5 minutes → 150°C curing for 20 minutes) to ensure stable resistivity of the conductive layer.

[0117] Antenna structure parameters:

[0118] Number of serpentine bending cycles: 4-6;

[0119] Line width / line spacing: 0.3mm / 0.2mm (applicable to 915MHz frequency band);

[0120] The total length matches half the wavelength of the target frequency band:

[0121]

[0122] 3. Electromagnetic performance verification and optimization

[0123] Simulation verification: Use HFSS or CST 3D electromagnetic field simulation software to optimize the antenna radiation pattern and input impedance: Set the substrate dielectric constant ε sub =3.5, loss factor tanδ = 0.002; load a metal backplane to simulate a metal environment, adjust the serpentine bending angle (45°-60°) to suppress surface waves; ensure the return loss S 11 ≤-15dB (within the target frequency band).

[0124] Measurement calibration: Use a vector network analyzer (VNA) to measure the antenna impedance and verify its compatibility with the chip impedance Z chip =30-j200Ω conjugate matching (Z in =30+j200Ω).

[0125] 4. Examples

[0126] Example 1:

[0127] Base: HN film, t1 = 50 μm;

[0128] Antenna: Snake dipole, total length L = 82mm, line width 0.3mm;

[0129] Performance: At 915MHz frequency, the measured gain is 2.1dBi and the reading distance (on metal surface) is 1.2m.

[0130] Example 2:

[0131] Substrate: Liquid crystal polymer (LCP), t1 = 75 μm, ε sub =2.9 antenna: dual-band structure (860MHz / 2.45GHz), line width 0.2mm / 0.1mm;

[0132] Performance: Dual-frequency return loss is ≤-18dB, and the read rate in liquid environment is ≥95%.

[0133] It should be noted that the substrate thickness is ≤100μm and can be adhered to curved surfaces with a radius of ≤5mm; 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 of a single label is ≤0.15 yuan.

[0134] S2. Covering the gradient dielectric material layer 202, the dielectric constant is exponentially distributed along the thickness direction:

[0135] ε r (z)=ε min ·e kz ,0≤z≤t2

[0136] Where k is the attenuation coefficient, t2 is the total thickness of the gradient layer, ε min is the minimum dielectric constant;

[0137] 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, the dielectric constant adjustment range is 2.1≤ε r≤120. Step S2 is the design and preparation process of the gradient dielectric material layer, and its specific implementation is as follows:

[0138] 1. Gradient dielectric material selection and formulation design

[0139] Material composition: A composite material of barium strontium titanate (BaSrTiO3, BST) and polytetrafluoroethylene (PTFE), with the dielectric constant controlled by volume ratio:

[0140] BST volume ratio: V BST :V PTFE =1:9~4:6, corresponding to the dielectric constant range ε r =2.1~120 (tested at 1MHz);

[0141] Function allocation:

[0142] BST: high dielectric constant component, improving near-field coupling efficiency;

[0143] PTFE: Low-loss flexible matrix, reducing dielectric loss (tanδ≤0.001).

[0144] Gradient distribution implementation:

[0145] Through the layered coating process, the dielectric constant is distributed exponentially along the thickness direction (z-axis):

[0146] ε r (z)=ε min ·e kz ,0≤z≤t2

[0147] Parameter settings:

[0148] Initial value: ε min =2.1 (surface, close to the environment);

[0149] End value: (bottom floor, near the antenna);

[0150] Attenuation coefficient: Typical value k = 0.05 ~ 0.2 μm -1 .

[0151] 2. Gradient layer preparation process

[0152] Process flow:

[0153] Slurry preparation: BST nanoparticles (particle size 50-100 nm) and PTFE emulsion (solid content 60%) were mixed at the target volume ratio and ultrasonically dispersed for 30 min to form a homogeneous slurry;

[0154] Layer by layer:

[0155] Use precision spraying equipment to spray layer by layer on the flexible substrate (antenna layer prepared in S1), with each layer thickness Δz = 5-10 μm;

[0156] The volume ratio of BST in each layer increases (e.g., from 10% to 40%), and a total of 10-20 layers are applied;

[0157] Gradient curing:

[0158] Stepwise heating: 80℃ pre-curing for 10min→180℃ hot pressing (pressure 0.5MPa, time 30min) to eliminate the interface between layers;

[0159] UV post-curing (wavelength 365nm, intensity 100mW / cm 2 , time 5min), enhance the bonding strength between layers. Thickness control:

[0160] The total thickness t2 is designed according to the operating frequency, and the typical value is:

[0161]

[0162] Among them, ε avg is the average dielectric constant of the gradient dielectric layer; operate is the free space wavelength corresponding to the target operating frequency of the tag; Example: If λ operate =32.8cm, ε avg =30, then t2≈1.8mm.

[0163] 3. Electromagnetic performance optimization and verification

[0164] Simulation Modeling:

[0165] Create a gradient dielectric layer model in CSTMicrowave Studio and set the exponential distribution parameter ε r (z); Load the metal or liquid environment boundary conditions and optimize the gradient parameters to make the reflection coefficient Γ≤-20dB;

[0166] Verify the improvement of energy transmission efficiency:

[0167]

[0168] Among them, P incident is the RF power incident on the tag antenna, P received is the power actually received by the tag chip, and η is the energy transmission efficiency.

[0169] Actual measurement verification:

[0170] Dielectric constant test: Use an impedance analyzer (such as Agilent 4294A) to measure the dielectric constant of each layer. rvalue, ensuring that the gradient distribution error is ≤ 5%;

[0171] Return loss test: Vector network analyzer (VNA) measures the antenna port S 11 ≤-18dB (860-960MHz band);

[0172] Environmental adaptability test:

[0173] Metal surface: reading distance ≥1.5m (traditional solution ≤0.8m);

[0174] Liquid container: recognition rate ≥98% (glycerol solution, ε r =50).

[0175] 4. Examples

[0176] Example 1:

[0177] Gradient parameters: k = 0.1 μm-1, t2 = 1.5 mm, ε min =2.1,ε max =50;

[0178] Performance: Energy transfer efficiency η = 68% in metal environment, S11 = -21dB in liquid environment.

[0179] Example 2:

[0180] Gradient parameters: k = 0.15 μm-1, t2 = 2.0 mm, ε min =2.1,ε max =80;

[0181] Performance: Reading distance fluctuation ≤±3% in heterogeneous media (metal + plastic) environment.

[0182] It should be noted that the gradient dielectric layer effectively reduces the dielectric interface reflection loss (≤-20dB) and improves the energy transmission efficiency by ≥20%; the exponential distribution design supports UHF to microwave frequency bands (400MHz-5.8GHz); it is suitable for roll-to-roll (R2R) continuous coating, with a production efficiency of ≥5000 pieces / hour.

[0183] S3. Add electromagnetic shielding isolation layer 203, whose surface impedance Z shield satisfy:

[0184] Z shield ≥5Z0 and σ shield ≥10 5 S / m

[0185] Where Z0 is the intrinsic impedance of free space, σ shield is the conductivity of the shielding material;

[0186] The electromagnetic shielding isolation layer (203) is a silver-plated nylon mesh with a mesh aperture d mesh satisfy:

[0187] And the opening rate is ≥85%.

[0188] Step S3 is the design and preparation process of the electromagnetic shielding isolation layer, and its specific implementation is as follows:

[0189] 1. Shielding material selection and structural design

[0190] Material selection:

[0191] Silver-plated nylon mesh is used as the core material of the shielding layer, and its characteristics are:

[0192] Surface impedance: Z shield ≥5Z0=5×377Ω=1885Ω, high impedance characteristics are achieved through mesh aperture design; conductivity: σ shield ≥105S / m, guaranteed by the thickness of the silver plating layer (≥2μm);

[0193] Flexible and compatible: Nylon base (thickness 50-100μm) ensures that the shielding layer can be bent (curvature radius ≤ 5mm). Grid parameter design:

[0194] Grid aperture d mesh satisfy

[0195] And the opening rate ≥85%

[0196] Example: If λ operate =32.8cm(915MHz), then d mesh ≤3.28cm, the actual aperture is 2.5cm;

[0197] Aperture ratio calculation: Aperture ratio = (d mesh / (d mesh +w wire )) 2 ×100%, where line width w wire =0.5mm, opening rate≈86%.

[0198] 2. Shielding layer preparation process

[0199] Process flow:

[0200] Substrate pretreatment: Plasma cleaning (Ar gas, power 150W, time 5min) of nylon mesh (200 mesh) to improve the adhesion of the coating;

[0201] Magnetron sputtering silver plating:

[0202] Vacuum degree: 5×10-3 Pa;

[0203] Sputtering power: 300W, coating thickness 2-3μm;

[0204] Square resistance after plating: ≤0.1Ω.

[0205] Hot pressing: The silver-plated grid and the gradient dielectric layer (prepared by S2) were compounded by hot pressing (temperature 120°C, pressure 0.3 MPa, time 10 min) to ensure that there were no bubbles between the layers.

[0206] Edge insulation treatment: Apply UV curing insulation glue (thickness 50μm) to prevent edge leakage.

[0207] Key parameter control:

[0208] Skin depth verification:

[0209] (For example, at 915MHz, δ≈1.2μm)

[0210] The thickness of the silver plating layer is ≥2μm, ensuring that the transmission loss under skin effect is ≤0.5dB.

[0211] 3. Shielding effectiveness verification and optimization

[0212] Test method:

[0213] Shielding Effectiveness (SE) test:

[0214] According to the IEEE 299 standard, a vector network analyzer (VNA) was used to measure the signal attenuation before and after shielding; the target SE was ≥ 30 dB (30 MHz-3 GHz frequency band).

[0215] Flexibility test:

[0216] The bending radius is 5mm. After 1000 bending cycles, the conductivity decreases by ≤5%.

[0217] Environmental tolerance:

[0218] After high temperature and high humidity (85℃ / 85%RH, 500h), the square resistance change is ≤10%.

[0219] Example:

[0220] Example 1:

[0221] The silver coating thickness is 2.5 μm and the mesh aperture is 2.5 cm;

[0222] Measured SE = 35dB (915MHz), after bending, SE remains ≥ 33dB;

[0223] Example 2:

[0224] Silver coating thickness 3μm, mesh aperture 1.8cm (applicable to 2.45GHz);

[0225] Measured SE = 40dB, weighs only 15g / m 2 , suitable for lightweight labels.

[0226] It should be noted that the present invention has the advantages of efficient 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 the liquid environment is ≥25dB; the total thickness is ≤150μm, and it can be bonded to complex curved surfaces (such as pipes and bottle bodies); the magnetron sputtering process supports roll-to-roll production, and the single-layer cost is ≤0.8 yuan / ㎡.

[0227] S4. Coating the self-repairing protective coating 204, whose thickness t3 and dielectric loss δ coating satisfy:

[0228] t3·tanδ coating ≤0.01λ operate .

[0229] The self-repairing protective coating (204) comprises a microencapsulated silicone material with a rupture threshold pressure P rupture satisfy:

[0230] P rupture ≥2σ coating / r capsule

[0231] Among them, σ coating is the Young's modulus of the coating, r capsule is the microcapsule radius.

[0232] Step S4 is the design and preparation process of the self-repairing protective coating, and its specific implementation is as follows:

[0233] 1. Selection and formulation design of self-healing materials

[0234] Material composition:

[0235] Microencapsulated Siloxane is used as the self-repairing functional component, and its core parameters are:

[0236] Microcapsule size: diameter r capsule =10-50μm, shell thickness t shell =1-3μm (polyurea material); repair agent content: silicone mass ratio ≥60%, microcapsule volume fraction 10%-15%;

[0237] Trigger mechanism: mechanical stress (rupture threshold P rupture≥2σ coating / r capsule ) or temperature (>50℃) triggers the release of the repair agent.

[0238] Base Material:

[0239] Polyurethane (PU) or epoxy resin is selected as the coating matrix, and its characteristics meet the following requirements:

[0240] Dielectric loss: tanδ coating ≤0.005(1MHz);

[0241] Flexibility: Elongation at break ≥ 200% (ASTM D638 standard).

[0242] 2. Coating preparation process

[0243] Process flow:

[0244] (1) Microcapsule dispersion: Siloxane microcapsules and PU prepolymer were mixed in a mass ratio of 1:9 and ultrasonically dispersed (40 kHz, 30 min) to ensure uniform distribution;

[0245] (2) Coating process:

[0246] Spraying: Use high-pressure airless spraying equipment (nozzle diameter 0.3 mm) to form a uniform coating on the surface of the shielding layer (prepared by S3) with a wet film thickness of 100-150 μm;

[0247] Curing: step-by-step curing (pre-curing at 60°C for 1 hour → final curing at 120°C for 2 hours) to form a cross-linked network;

[0248] (3) Thickness control: According to the formula t3·tanδ coating ≤0.01λ operate , calculate the maximum allowable thickness:

[0249] Example: If λ operate =32.8cm, tanδ coating =0.004, then t3≤0.01×0.328 / 0.004≈0.82mm, and t3=50μm is actually selected.

[0250] 3. Self-healing performance verification

[0251] Burst threshold test:

[0252] The coating rupture threshold P was measured by nanoindentation rupture , verify the formula

[0253] P rupture ≥2σ coating / r capsule

[0254] Example: If the coating Young's modulus σ coating =1.5GPa, microcapsule radius r capsule =20μm, then:

[0255] (measured value ≥2.0×10 8 Pa)

[0256] Repair efficiency test:

[0257] Scratch repair: Use a blade to make a scratch with a depth of 50 μm, and observe the repair status within 24 hours at 25°C (optical microscope);

[0258] Electrical performance recovery: Measure the change in tag reading distance before and after repair (target: recovery rate ≥ 80%);

[0259] Environmental durability:

[0260] Repair efficiency ≥70% after high temperature and high humidity (85℃ / 85%RH, 500h);

[0261] Hot and cold cycle ( 100 times) after the coating has no delamination.

[0262] 4. Examples

[0263] Example 1:

[0264] Coating parameters: t3 = 50 μm, microcapsule volume fraction 12%;

[0265] Performance: 85% of scratches (50μm) were repaired within 18 hours, and the reading distance was restored from 1.2m to 1.0m.

[0266] Example 2:

[0267] Coating parameters: t3 = 80 μm, microcapsule volume fraction 15%;

[0268] Performance: After 100 bending cycles (curvature radius 5mm), the coating has no cracks and the dielectric loss remains at tanδ=0.0038.

[0269] It should be noted that the present invention has the advantages of dynamic repair capability, electrical compatibility and environmental robustness. After the microcapsule is ruptured, the silicone filling rate is ≥90%, and the repair response time is ≤24h (25°C); the ultra-low dielectric loss (tanδ≤0.005) ensures that the coating's impact on RFID signals is ≤3%; and it has passed a 5-year accelerated aging test (IEC 60068-2 standard) with performance degradation ≤10%.

[0270] This embodiment also provides a computer device suitable for the RFID tag packaging method for a multimedia environment, 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 packaging method for a multimedia environment as proposed in the above embodiment.

[0271] The computer device may be a terminal, comprising a processor, a memory, a communication interface, a display screen and an input device connected via a system bus. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device comprises a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner may be achieved through WIFI, an operator network, NFC (near field communication) or other technologies. The display screen of the computer device may be a liquid crystal display or an electronic ink display screen, and the input device of the computer device may be a touch layer covering the display screen, or a button, trackball or touchpad provided on the housing of the computer device, or an external keyboard, touchpad or mouse.

[0272] This embodiment also provides a storage medium having a computer program stored thereon. When the program is executed by a processor, the program implements the RFID tag packaging method for a multi-media environment as proposed in the above embodiment. 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 read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, magnetic disk or optical disk.

[0273] In summary, the present invention uses dynamic impedance matching and environmental perception feedback mechanisms, and the system can detect the dielectric properties of media such as metals and liquids in real time, and use the particle swarm optimization algorithm to dynamically adjust the working frequency band and impedance matching parameters, so that the energy transmission efficiency of the tag in a complex media environment is improved by more than 40%, and the reading distance stability is improved to within ±5%. The multi-band reconfigurable antenna array (frequency band covering 860MHz-2.45GHz) is combined with a serpentine folded dipole structure to effectively suppress surface wave interference, and the radiation efficiency reaches more than 75% (traditional tags <50%). The gradient dielectric material layer achieves a smooth transition of electromagnetic field energy from the substrate to the environment through a gradient distribution of the dielectric constant, reducing the reflection loss at the dielectric interface (reflection coefficient ≤-20dB). The electromagnetic shielding isolation layer, combined with the silver-plated nylon mesh structure, attenuates the environmental coupling interference by more than 30dB, while maintaining an opening rate of more than 85%, ensuring that the tag is flexible and bendable (curvature radius ≤5mm). The multi-tag collision protocol based on the dynamic weighted fusion algorithm improves the recognition efficiency by 60% in dense deployment scenarios (>200 tags / ㎡), and the misreading rate is less than 0.1%. The self-healing protective coating can repair more than 80% of microcracks within 24 hours. Combined with the temperature compensation circuit, the life of the tag is extended to more than 5 years in extreme environments of -40℃ to 85℃. The flexible polyimide substrate supports roll-to-roll printing process, and the manufacturing cost of a single tag is reduced by 30%, making it suitable for large-scale industrial applications. This solution overcomes the technical bottlenecks of RFID tag impedance mismatch, frequency band rigidity and poor packaging reliability in multi-media environments. In complex industrial scenarios (such as metal pipeline monitoring and liquid drug traceability), the average recognition rate is increased from 65% of traditional solutions to more than 98%, providing a highly robust and low-power radio frequency identification solution for the perception layer of the Internet of Things.

[0274] 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 the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. An RFID tag adaptive separation system for a multi-media environment, characterized in that: include: A multi-band reconfigurable antenna array (101) is composed of N radiating elements, and its resonant frequency satisfies: Among them, L n is the length of the nth radiation unit, ε eff is the equivalent dielectric constant, c is the speed of light; Embedded environment sensing module (102), used to detect the dielectric constant ε of the medium in which the tag is located r And loss factor tanδ, its output parameters satisfy: Among them, C meas is the measured capacitance, d is the dielectric thickness, ε0 is the angular frequency, A is the electrode area, G is the conductivity, and ω is the angular frequency; Adaptive impedance tuning circuit (103) adjusts antenna input impedance Z in real time through varactor diode array in , so that it is consistent with the chip impedance Z chip Match, satisfy: in, is the conjugate complex number of the chip impedance, R chip is the equivalent resistance of the chip, X chip is the equivalent reactance of the chip; The intelligent control unit (104) dynamically selects the optimal operating frequency band and impedance matching parameters through a particle swarm optimization algorithm based on the data of the embedded environment sensing module (102).

2. The RFID tag adaptive separation system for a multi-media environment according to claim 1, characterized in that: The multi-band reconfigurable antenna array (101) adopts a serpentine folded dipole structure, and the spacing ΔL between adjacent radiating elements satisfies: Among them, f min is the lowest operating frequency of the system, N is the number of radiation units, λ max is the maximum wavelength corresponding to the lowest operating frequency supported by the system, and c is the speed of light.

3. The RFID tag adaptive separation system for a multi-media environment according to claim 1, characterized in that: The embedded environment sensing module (102) integrates a temperature compensation circuit, and its dielectric constant correction formula is: e' r =e r ·[1+γθ(T-T0)],γ=-0.0025 / ℃ Wherein, T is the ambient temperature, T0 is the reference temperature, T0=25°C, and γ is the temperature coefficient of the dielectric constant.

4. The RFID tag adaptive separation system for a multi-media environment according to claim 1, wherein: The adaptive impedance tuning circuit (103) comprises a π-type matching network, the matching parameters of which are determined by the following formula: Among them, R ant is the antenna equivalent resistance, R chip is the chip equivalent resistance, X chip is the equivalent reactance of the chip, 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 a multi-media environment according to claim 1, wherein: The intelligent control unit (104) adopts a dynamic weighted fusion algorithm, and its objective function is: Among them, P received is the received power, Q factor is the antenna quality factor, P threshold is the power threshold, Q min is the minimum antenna quality factor required by the system, and α and β are dynamic weighting factors used to balance the optimization weight between the received power and the antenna quality factor.

6. The RFID tag adaptive separation system for a multi-media environment according to claim 1, wherein: The system supports a multi-tag collision avoidance protocol with a random backoff time t backoff satisfy: Among them, retry is the number of retries, BW is the channel bandwidth, RSSI max RSSI is the maximum received signal strength value among all tag signals detected in the current communication scenario. current It is the signal strength value of a specific tag detected by the reader in the most recent communication.

7. A method for packaging RFID tags for a multi-media environment, which is implemented based on the RFID tag adaptive separation system for a multi-media environment according to any one of claims 1 to 6, characterized in that: The following steps are involved: S1. Printing antenna radiation unit on flexible polyimide substrate (201), substrate thickness t1 satisfies Among them, ε sub is the substrate dielectric constant, λ operate is the free space wavelength of the antenna at the target operating frequency; S2. Covering the gradient dielectric material layer (202), the dielectric constant of which is distributed according to an exponential law along the thickness direction: e r (z)=e min ·e kz ,0≤x≤t2 Where k is the attenuation coefficient, t2 is the total thickness of the gradient layer, ε min is the minimum dielectric constant; S3. Add an electromagnetic shielding isolation layer (203), whose surface impedance Z shield satisfy: Z shield ≥5Z0 and σ shield ≥10 5 S / m Where Z0 is the intrinsic impedance of free space, σ shield is the conductivity of the shielding material; S4. Applying a self-repairing protective coating (204), the thickness t3 of which is related to the dielectric loss δ coating satisfy: <h2 style=";text-align:left;direction:ltr">t3·tanδ<h2 style=";text-align:left;direction:ltr"> coating <h2 style=";text-align:left;direction:ltr"> ≤0·01λ<h2 style=";text-align:left;direction:ltr"> operate <h2 style=";text-align:left;direction:ltr"> 。 8. The RFID tag packaging method for a multimedia environment according to claim 7, wherein: 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, the dielectric constant adjustment range is 2.1≤ε r ≤120.

9. The RFID tag packaging method for a multimedia environment according to claim 7, wherein: The electromagnetic shielding isolation layer (203) is a silver-plated nylon mesh with a mesh aperture d mesh satisfy: And the opening rate is ≥85%.

10. The RFID tag packaging method for a multimedia environment according to claim 7, wherein: The self-repairing protective coating (204) comprises a microencapsulated silicone material, the rupture threshold pressure P rupture satisfy: P rupture ≥2σ coating / r capsule Among them, σ coating is the Young's modulus of the coating, r capsule is the microcapsule radius.

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