Flexible anti-metal tag antenna

Abstract

The utility model discloses a flexible anti-metal tag antenna, which comprises an antenna main body, the antenna main body comprises a radiation part, a short circuit part and a grounding part, the antenna main body is folded through the short circuit part, the radiation part is positioned above the grounding part, the size of the radiation part is smaller than that of the grounding part, and the grounding part is positioned above the radiation part. After being folded, the radiation part and the grounding part are separated through foam rubber, and the grounding part is in contact with a metal object. According to the tag antenna structure, the antenna efficiency can be improved, so that the tag antenna structure can adapt to frequency band requirements of different countries and regions, and good performance can be kept in a metal environment.

Description

Technical Field

[0001] The utility model relates to the technical field of electronic tags, in particular to a flexible anti-metal tag antenna. Background Art

[0002] Traditional dipole antennas have the following common problems:

[0003] 1. Impedance matching issues cannot be effectively addressed, limiting antenna efficiency. Impedance matching is limited. Electronic tag chips have varying impedances, but traditional antennas struggle to flexibly adjust to these varying chip impedances. Their fixed impedance matching strategy cannot accommodate diverse chip impedance requirements, making it difficult to achieve optimal antenna efficiency.

[0004] 2. Lack of dynamic adaptability to different frequency bands. RFID frequency bands vary across countries and regions. Existing antennas lack effective adjustment mechanisms to accommodate these differences, making them unable to maintain good performance across different frequency bands, limiting their global application.

[0005] 3. Poor performance in metallic environments, unable to meet practical application requirements. When conventional antennas are placed on metal surfaces, their performance is severely affected by the metal. The metal alters the electromagnetic field distribution around the antenna, causing changes in parameters such as the antenna's resonant frequency and impedance, which in turn significantly degrades antenna performance. Some existing metal-resistant designs are structurally inadequate and cannot achieve effective metal shielding while maintaining antenna performance. Utility Model Content

[0006] The purpose of the utility model is to solve the shortcomings of the prior art and to propose a flexible anti-metal tag antenna.

[0007] In order to achieve the above purpose, the present invention adopts the following technical solutions:

[0008] A flexible anti-metal tag antenna includes an antenna body, which includes a radiating portion, a short-circuit portion, and a grounding portion. The antenna body is folded through the short-circuit portion, and the radiating portion is located above the grounding portion. The radiating portion is smaller than the grounding portion. After folding, the radiating portion and the grounding portion are separated by foam glue, and the grounding portion contacts a metal object.

[0009] Preferably, the radiation portion, the short-circuit portion and the grounding portion are integrally formed.

[0010] Preferably, the radiation portion includes a coupling slot, a coupling line, and a bonding slot. The shape of the coupling slot is adjustable, and the length, shape, and direction of the coupling line are adjustable.

[0011] Preferably, the short-circuit portion includes a coupling slot and a frequency band adjustment line, and the position of the frequency band adjustment line is adjustable.

[0012] Compared with the existing technology, the beneficial effects of the utility model are:

[0013] The structure of the utility model can improve the efficiency of the antenna, so that it can adapt to the frequency band requirements of different countries and regions and maintain good performance in a metal environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a schematic diagram of the unfolded structure of a flexible anti-metal tag antenna proposed in the present invention.

[0015] In the figure: a radiating portion 10 , a short-circuit portion 20 , a grounding portion 30 , a coupling slot 11 , a coupling line 12 , a bonding slot 13 , a coupling slot 21 , and a frequency band adjustment line 22 . DETAILED DESCRIPTION

[0016] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0017] Reference Figure 1 A flexible metal-resistant tag antenna includes a radiating portion 10, a shorting portion 20, and a grounding portion 30. The radiating portion 10 includes a coupling slot 11, a coupling line 12, and a bonding slot 13. The shorting portion 20 includes a coupling slot 21 and a frequency band adjustment line 22. The radiating portion 10, shorting portion 20, and grounding portion 30 are integrally formed. The antenna is folded through the shorting portion 20, with the radiating portion 10 on top and slightly smaller than the grounding portion 30. The radiating portion 10 is folded in half and separated by foam glue, while the grounding portion 30 is at the bottom, contacting the metal object.

[0018] Compared to traditional dipole antennas, this antenna utilizes an embedded, adjustable coupling slot 11 and coupling line 12 to achieve conjugate matching, optimizing antenna efficiency. This represents an impedance matching strategy distinct from traditional methods. Different electronic tag chips have varying impedances, and the shape of the coupling slot 11 is adjusted to increase the degree of freedom in impedance matching. The length, shape, and direction of the coupling line 12 are adjusted to control the current path and length, thereby adjusting the impedance. This allows the antenna to achieve conjugate impedance matching tailored to the impedance conditions of different electronic tag chips, adapting to all commercially available tag chips. The remaining radiating portion 10 and coupling line 12, hollowed out by the coupling slot 11, provide energy storage and radiation. The bonding slot 12 is used to heat-bond the tag chip with conductive adhesive for tag identification and reading.

[0019] The coupling slot 21 in the short-circuit portion 20 can optimize the coupling degree between the radiating portion 10 and the grounding portion 30, achieve good impedance matching, and improve antenna performance. The frequency band adjustment line 22 is an identification line used to identify the folding position of the antenna during the production of the flexible anti-metal tag production equipment. The RFID frequency bands in different countries and regions are different. By adjusting the position of the frequency band adjustment line 22 so that the fold is biased forward or backward, the center frequency of the final flexible anti-metal tag product can be adjusted, so that the tag can be dynamically adjusted in the RFID ultra-high frequency band divided by various countries and regions during production according to the actual frequency band requirements.

[0020] When a conventional antenna is placed on a metal surface, its performance will be affected by the metal and deteriorate dramatically. However, this application connects the radiating portion 10 and the grounding portion 30 via a shorting portion 20, allowing the grounding portion 30 to isolate the radiating portion 10 from the metal, thereby improving the electronic tag's adaptability in metal environments. To better shield the metal environment, the grounding portion 30 is designed to be slightly larger than the radiating portion 10. For example, a tag measuring 105*65mm, using 0.8mm thick foam adhesive, can achieve a theoretical read range of 16m in HFSS electromagnetic simulation software. The performance degradation caused by the -10dB bandwidth in the return loss S11 is stabilized below 10%. In actual anti-metal application scenarios, the read range measured using a handheld device can reach 13m, which is superior to similarly sized products on the market.

[0021] The specific impedance matching process of the antenna provided in this embodiment is as follows:

[0022] The antenna utilizes an embedded, adjustable coupling slot 11 and coupling line 12 to achieve conjugate matching for optimal antenna efficiency. Different electronic tag chips have varying impedances, and adjusting the shape of the coupling slot 11 increases the degree of freedom in impedance matching. Adjusting the length, shape, and direction of the coupling line 12 controls the current path and length, thereby adjusting the impedance. This allows the antenna to achieve conjugate matching based on the impedance conditions of different electronic tag chips, adapting to all commercially available tag chips. The remaining radiating portion 10 hollowed out by the coupling slot 11 and the coupling line 12 provide energy storage and radiation. The bonding slot 13 is used to heat-bond the tag chip with conductive adhesive for tag identification and reading. Adjusting the shape of the coupling slot 11 affects the electromagnetic field distribution, thereby changing the antenna's impedance characteristics. Changing the shape of the coupling slot 11 also alters the electromagnetic field propagation path and pattern within it, affecting the coupling between the antenna and the chip. The length, shape, and direction of the coupling line 12 play a key role in controlling the current path and length. Precisely adjusting these parameters of the coupling line 12 optimizes the current distribution within the antenna, achieving conjugate matching with the chip's impedance. For example, when the length of the coupling line 12 increases, the current path becomes longer, which will cause the impedance to change. By reasonably designing the shape and direction of the coupling line 12, this change can be compensated to achieve the best conjugate matching state between the antenna and the chip.

[0023] The specific frequency band adjustment process of the antenna provided in this embodiment is as follows:

[0024] The coupling slot 21 in the short-circuit portion 20 can optimize the coupling degree between the radiating portion 10 and the grounding portion 30, achieve good impedance matching, and improve antenna performance. The frequency band adjustment line 22 is an identification line used to identify the folding position of the antenna during the production of the flexible anti-metal tag production equipment. The RFID frequency bands in different countries and regions are different. By adjusting the position of the frequency band adjustment line 22 so that the fold is biased forward or backward, the center frequency of the final flexible anti-metal tag product can be adjusted, so that the tag can be dynamically adjusted in the RFID ultra-high frequency band divided by each country and region during production according to the actual frequency band requirements. The frequency band adjustment line 22 plays the role of a reference mark in the antenna structure. When the center frequency of the tag needs to be adjusted to adapt to the RFID frequency bands in different regions during the production process, the position of the antenna fold can be changed by moving the position of the frequency band adjustment line 22. The change in the folding position of the antenna will affect the coupling relationship between the radiating portion 10 and the grounding portion 30, thereby changing the resonant frequency of the antenna. When the folding position is biased forward or backward, the electromagnetic field distribution between the radiating portion 10 and the ground portion 30 will change, causing the equivalent circuit parameters of the antenna to change, thereby achieving adjustment of the center frequency.

[0025] The antenna provided in this embodiment has the following specific design process for metal environment adaptability:

[0026] When a conventional antenna is placed on a metal surface, its performance will be affected by the metal and deteriorate dramatically. This design connects the radiating portion 10 and the grounding portion 30 via a shorting portion 20, allowing the grounding portion 30 to isolate the radiating portion 10 from the metal. To better shield the metal environment, the grounding portion 30 is designed to be slightly larger than the radiating portion 10. When the grounding portion 30 comes into contact with a metal object, it can effectively guide the reflected signal from the metal surface to the ground, reducing the impact of the reflected signal on the antenna performance and forming a wider shielding area. When electromagnetic signals propagate around the antenna, the grounding portion 30 can effectively guide the reflected signal from the metal surface to the ground, reducing the impact of the reflected signal on the antenna performance. The grounding portion 30 is connected to the radiating portion 10 via the shorting portion 20. This connection method ensures that the grounding portion 30 can promptly conduct any metal interference signals that may be received by the radiating portion 10 to the ground, thereby maintaining the condition of the radiating portion 10 and further improving the performance of the antenna in a metal environment.

[0027] The above is only a preferred specific implementation method of the present invention, but the protection scope of the present invention is not limited to this. Any technician familiar with the technical field within the technical scope disclosed by the present invention can make equivalent replacements or changes based on the technical solution and utility model concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A flexible anti-metal tag antenna, comprising an antenna body, characterized in that: The antenna body comprises a radiation part (10), a short-circuit part (20), and a grounding part (30); the antenna body is folded through the short-circuit part (20); the radiation part (10) is located above the grounding part (30); and the size of the radiation part (10) is smaller than that of the grounding part (30); after being folded in half, the radiation part (10) and the grounding part (30) are separated by foam glue, and the grounding part (30) contacts a metal object.

2. The flexible anti-metal tag antenna according to claim 1, characterized in that: The radiation portion (10), the short-circuit portion (20) and the grounding portion (30) are integrally formed.

3. The flexible anti-metal tag antenna according to claim 1, characterized in that: The radiation part (10) comprises a coupling slot (11), a coupling line (12), and a bonding slot (13); the shape of the coupling slot 11 is adjustable, and the length, shape, and direction of the coupling line 12 are adjustable.

4. The flexible anti-metal tag antenna according to claim 1, characterized in that: The short-circuit portion (20) comprises a coupling slot (21) and a frequency band adjustment line (22), and the position of the frequency band adjustment line (22) is adjustable.

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