Broadband anti-metal RFID tag antenna

Abstract

The utility model discloses a broadband anti-metal RFID tag antenna, which comprises an antenna conducting layer and a chip, the antenna conducting layer comprises an antenna layer, a side surface connecting layer and a back surface metal layer, the antenna layer and the back surface metal layer are of sheet-shaped rectangular structures, and the chip is arranged on the chip. The antenna layer and the back metal layer which are vertically parallel to each other are connected through the side connecting layer to form an integral structure, the antenna layer is provided with an inverted-L-shaped hollow section, a first slot, a second slot and a third slot, the inverted-L-shaped hollow section is located at the edge of the antenna layer, and the short edge of the inverted-L-shaped hollow section is provided with a disconnected opening. The chip is connected to an opening of the L-shaped hollow section through a conductive adhesive to form a closed loop, and the first slot, the second slot and the third slot are arranged on opposite sides of the antenna layer to form an impedance adjusting array together. Through the above mode, the antenna provided by the utility model has better impedance bandwidth and antenna gain, and can be matched with different chips by conveniently adjusting impedance, thereby adapting to a metal use environment.

Description

Technical Field

[0001] This utility model relates to the field of antenna technology, and in particular to a broadband anti-metal RFID tag antenna. Background Technology

[0002] RFID (Radio Frequency Identification) technology is one of the key supporting technologies for the Internet of Things (IoT). Typically, an RFID system consists of tags, readers, and servers. Data is collected through tags and readers, and then processed by the server. RFID has multiple communication frequency bands. For ultra-high frequency (UHF) (860MHz-960MHz), the tag reading distance can reach more than 10m by utilizing the backscattering principle of electromagnetic waves. To optimize the entire RFID system, impedance matching between the RFID antenna and the chip is required. Due to limitations in antenna manufacturing processes and cost control, external components cannot be used to achieve impedance matching; it can only be achieved by adjusting the antenna structure.

[0003] With the increasing application of UHF RFID, many applications require tags to be used on metal backing surfaces. Conventional dipole antennas have very short reading distances due to the influence of metal eddy currents. To achieve the goal of using RFID tags on metal, the antenna is usually raised by adding a thin layer of foam of about 1mm between the antenna and the metal to reduce the influence of the metal on the tag. However, this makes the antenna design for anti-metal tags more complicated and the antenna impedance matching bandwidth narrow, which cannot meet the broadband frequency band requirements of 860-960MHz. Utility Model Content

[0004] The main technical problem solved by this utility model is to provide a broadband anti-metal RFID tag antenna with good impedance bandwidth and antenna gain, and the impedance can be easily adjusted to match different chips and adapt to metal usage environments.

[0005] To solve the above-mentioned technical problems, the present invention provides a broadband anti-metal RFID tag antenna, which includes an antenna conductive layer and a chip. The antenna conductive layer includes an antenna layer, a side connection layer, and a back metal layer. The antenna layer and the back metal layer are sheet-like rectangular structures. The antenna layer and the back metal layer, which are parallel to each other, are connected by the side connection layer to form an integral structure, thereby effectively reducing the influence of metal eddy currents on the tag and achieving an anti-metal effect. The antenna layer has an inverted L-shaped hollow section, a first slot, a second slot, and a third slot. The inverted L-shaped hollow section is located at the edge of the antenna layer and its short side has a break opening. The chip is connected to the opening of the L-shaped hollow section by conductive adhesive to form a closed loop. The first slot, the second slot, and the third slot are located on opposite sides of the antenna layer, together forming an impedance adjustment array. A surface layer is attached to the outer surface of the antenna conductive layer by a double-sided adhesive layer. An insulating material layer is attached between the antenna layer and the back metal layer by a double-sided adhesive layer. The entire tag antenna structure is attached to the managed item by a fourth double-sided adhesive layer.

[0006] Preferably, the inverted L-shaped cutout segment is located at the upper edge of the antenna layer, and the longer side of the inverted L-shaped cutout segment is greater than the shorter side. By changing the length of the longer side of the inverted L-shaped cutout segment, the coupling strength between the antenna cutout segment and the entire antenna layer and the impedance bandwidth of the antenna can be enhanced, thereby increasing the antenna bandwidth. By changing the length of the shorter side of the inverted L-shaped cutout segment, the imaginary part of the antenna impedance can be easily adjusted. By adjusting the impedance adjustment array distribution of the first slot, the second slot, and the third slot, the frequency point of the antenna can be effectively adjusted.

[0007] Preferably, the antenna conductive layer is made of a metallic conductive material such as aluminum, copper, or graphene, and the antenna conductive layer is located on a substrate material, which is an insulating material such as PET film, PI film, or paper.

[0008] Preferably, the surface layer is made of a flexible printable material such as PET film or copperplate paper to protect the chip and antenna, and can be printed with images or QR codes.

[0009] Preferably, the insulating material layer is made of foamed cotton, synthetic paper, or plastic, which provides support for the tag antenna and increases its flexibility, while separating the antenna layer from the back metal layer to reduce the impact of metal eddy currents on the tag signal.

[0010] Preferably, the double-sided adhesive layer material is acrylic substrate-free double-sided adhesive.

[0011] Preferably, the fourth double-sided adhesive layer material is a foam adhesive, a substrate-based double-sided adhesive, or a silicone adhesive material with adhesive properties.

[0012] Compared with the prior art, the beneficial effects of this utility model are:

[0013] By changing the long side of the inverted L-shaped cutout section, the coupling strength between the cutout section and the entire antenna layer, as well as the impedance bandwidth of the antenna, can be enhanced, thereby increasing the antenna bandwidth.

[0014] The imaginary part of the antenna impedance can be easily adjusted by changing the length of the short side of the inverted L-shaped cutout section.

[0015] By adjusting the impedance distribution of the first, second, and third slots, the frequency of the antenna can be effectively adjusted.

[0016] The antenna layer and the back metal layer, which are parallel to each other, are connected by a side layer to form an integral structure, which effectively reduces the impact of metal eddy currents on the tag and achieves an anti-metal effect. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of a broadband anti-metal RFID tag antenna.

[0018] Figure 2 This is a top view of the antenna conductive layer of a broadband anti-metal RFID tag antenna.

[0019] Figure 3 This is a schematic diagram of the conductive layer structure of a broadband anti-metal RFID tag antenna.

[0020] Among them, 1. Antenna conductive layer, 101. Antenna layer, 102. Side connection layer, 103. Back metal layer, 104. Inverted L-shaped hollow section, 105. First slot, 106. Second slot, 107. Second slot, 2. Chip, 3. Surface layer, 4. First double-sided adhesive layer, 5. Second double-sided adhesive layer, 6. Insulating material layer, 7. Third double-sided adhesive layer, 8. Fourth double-sided adhesive layer. Detailed Implementation

[0021] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the scope of protection of the present invention.

[0022] Please see Figures 1 to 3 The embodiments of this utility model include:

[0023] A broadband anti-metal RFID tag antenna includes an antenna conductive layer 1, a chip 2, a surface layer 3, a first double-sided adhesive layer 4, a second double-sided adhesive layer 5, an insulating material layer 6, a third double-sided adhesive layer 7, and a fourth double-sided adhesive layer 8.

[0024] The antenna conductive layer 1 includes an antenna layer 101, a side connection layer 102, and a back metal layer 103. The antenna layer 101 and the back metal layer 103 are sheet-like rectangular structures. The antenna layer 101 and the back metal layer 103, which are parallel to each other, are connected by the side connection layer 102 to form an integral structure, thereby effectively reducing the influence of metal eddy currents on the label and achieving an anti-metal effect. The antenna layer 101 has an inverted L-shaped cutout section 104, a first slot 105, a second slot 106, and a third slot 107. The inverted L-shaped cutout section 104 is located at the edge of the antenna layer 101 and its short side is provided with a break opening. The chip 2 is connected to the opening of the L-shaped cutout section 104 by conductive adhesive to form a closed loop. The first slot 105, the second slot 106, and the third slot 107 are arranged on opposite sides of the antenna layer 101, which together form an impedance adjustment array.

[0025] The inverted L-shaped cutout segment 104 is located on the upper edge of the antenna layer 101, and the longer side of the inverted L-shape of the cutout segment is greater than the shorter side. By changing the length of the longer side of the inverted L-shaped cutout segment 104, the coupling strength between the cutout segment 104 and the entire antenna layer 101 and the impedance bandwidth of the antenna can be enhanced, thereby increasing the antenna bandwidth. By changing the length of the shorter side of the inverted L-shaped cutout segment 104, the imaginary part of the antenna impedance can be easily adjusted. By adjusting the impedance adjustment array distribution of the first slot 105, the second slot 106, and the third slot 107, the frequency point of the antenna can be effectively adjusted.

[0026] The antenna conductive layer 1 serves as the third layer of the antenna. The antenna conductive layer 1 is made of conductive metal materials such as aluminum, copper, and graphene. The antenna conductive layer 1 is located on a substrate material, which is usually an insulating material such as PET film, PI film, or paper.

[0027] The surface layer 3 serves as the first layer of the antenna. The surface layer 3 is bonded to the antenna conductive layer 1 by the first double-sided adhesive layer 4. The surface layer 3 is typically a flexible printable material such as PET film or copperplate paper. This layer can protect the chip 2 and the antenna, and can be printed with images, QR codes, etc.

[0028] The insulating material layer 6 serves as the fifth layer of the antenna. It is made of materials such as foamed cotton, synthetic paper, or plastic. The upper and lower surfaces of the insulating material layer 6 are bonded to the antenna conductive layer 1 via a second double-sided adhesive layer 5 and a third double-sided adhesive layer 7, respectively. The upper surface of the insulating material layer 6 is bonded to the antenna layer 101 via the second double-sided adhesive layer 5, and the lower surface of the insulating material layer 6 is bonded to the back metal layer 103 via the third double-sided adhesive layer 7. This provides support for the tag antenna and increases its flexibility, while also separating the antenna layer 101 from the back metal layer 103, reducing the impact of metal eddy currents on the tag signal. The dielectric constant of the insulating material layer 6 also affects the frequency of the tag antenna; therefore, high consistency in material performance must be ensured in actual production.

[0029] The tag antenna is attached to the managed item via the fourth double-sided adhesive layer 8.

[0030] The first, second, and third double-sided adhesive layers are made of acrylic substrate-free double-sided adhesive, which has high adhesion and can be applied to various surfaces. Meanwhile, the fourth double-sided adhesive layer 8 can be made of foam adhesive, substrate-based double-sided adhesive, silicone, or other adhesive materials.

[0031] This utility model discloses a broadband anti-metal RFID tag antenna, which has good impedance bandwidth and antenna gain, and the impedance can be easily adjusted to match different chips and adapt to metal usage environments.

[0032] The above description is merely an embodiment of this utility model and does not limit the patent scope of this utility model. Any equivalent structural or procedural transformations made based on the description and drawings of this utility model, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. A broadband anti-metal RFID tag antenna, comprising an antenna conductive layer (1) and a chip (2), characterized in that: The antenna conductive layer (1) includes an antenna layer (101), a side connection layer (102), and a back metal layer (103). The antenna layer (101) and the back metal layer (103) are sheet-like rectangular structures. The antenna layer (101) and the back metal layer (103), which are parallel to each other, are connected by the side connection layer (102) to form an integral structure. The antenna layer (101) has an inverted L-shaped hollow section (104), a first slot (105), a second slot (106), and a third slot (107). The inverted L-shaped hollow section (104) is located at the edge of the antenna layer (101). Furthermore, a break opening is provided on its short side. The chip (2) is connected to the opening of the L-shaped hollow section (104) by conductive adhesive to form a closed loop. The first slot (105), the second slot (106) and the third slot (107) are provided on the opposite side of the antenna layer (101) to form an impedance adjustment array. The outer surface of the antenna conductive layer (1) is pasted with a surface layer (3) by double-sided adhesive. An insulating material layer (6) is pasted between the antenna layer (101) and the back metal layer (103) by double-sided adhesive. The entire structure of the tag antenna is pasted onto the managed item by a fourth double-sided adhesive layer (8).

2. The broadband anti-metal RFID tag antenna according to claim 1, characterized in that: The inverted L-shaped hollow section (104) is located on the upper edge of the antenna layer (101), and the long side of the inverted L-shaped hollow section is greater than the short side of the inverted L-shaped hollow section. By changing the length of the long side of the inverted L-shaped hollow section (104), the coupling strength between the antenna hollow section (104) and the entire antenna layer (101) and the impedance bandwidth of the antenna are enhanced, thereby increasing the antenna bandwidth. The imaginary part of the antenna impedance is adjusted by changing the length of the short side of the inverted L-shaped hollow section (104), and the frequency point of the antenna is adjusted by adjusting the impedance adjustment array distribution of the first slot (105), the second slot (106), and the third slot (107).

3. The broadband anti-metal RFID tag antenna according to claim 1, characterized in that: The antenna conductive layer (1) is made of aluminum, copper or graphene, which are metallic conductive materials. The antenna conductive layer 1 is located on a substrate material, which is an insulating material such as PET film, PI film or paper.

4. The broadband anti-metal RFID tag antenna according to claim 1, characterized in that: The surface layer (3) is made of a flexible printable material such as PET film or copperplate paper, used to protect the chip (2) and the antenna.

5. A broadband anti-metal RFID tag antenna according to claim 1, characterized in that: The insulating material layer (6) is made of foamed cotton, synthetic paper or plastic, which provides support for the tag antenna and increases its flexibility, while separating the antenna layer (101) and the back metal layer (103).

6. The broadband anti-metal RFID tag antenna according to claim 1, characterized in that: The double-sided adhesive layer material is acrylic substrate-free double-sided adhesive.

7. A broadband anti-metal RFID tag antenna according to claim 1, characterized in that: The fourth double-sided adhesive layer (8) is made of foam adhesive, double-sided adhesive with a substrate, or silicone, which are adhesive materials.

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