A rolling type metal resistant ultra-high frequency RFID tag antenna

Abstract

The application relates to the technical field of wireless communication, in particular to a rolling type metal-resistant ultra-high frequency RFID tag antenna, which comprises cylindrical insulation support members arranged coaxially at two sides, a plurality of radiation arms are arranged at intervals along the circumferential direction of the insulation support members and tightly arranged at two ends of the two insulation support members respectively, a grounding arm is arranged between the two adjacent radiation arms, one end of the radiation arm and the grounding arm is connected with a short-circuit wall, a chip is arranged between the two insulation support members, a feeding surface and a grounding surface are connected with the chip through lead sheets at two ends of the chip, the feeding surface is connected with the radiation arm, the grounding surface is connected with the grounding arm, or the feeding surface is connected with the grounding arm, and the grounding surface is connected with the radiation arm. The frequency point offset of the RFID tag antenna when placed randomly is not more than the application frequency band, the RFID tag antenna has good directivity and is suitable for application in an Internet of Things intelligent identification system.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of wireless communication, and in particular to a rolling type anti-metal ultra-high frequency RFID tag antenna. BACKGROUND

[0002] Radio frequency identification (RFID) is mainly composed of three parts: the first part is the transponder: generally, it is a tag, and the tag is designed according to different use scenarios. The second part is the reader: a device used to read and write information to the tag. The third part is the application software system: according to different scenarios, the collected data is further processed and used by people.

[0003] The first application of the RFID system in reality was in the United Kingdom during World War II. The United Kingdom used RFID tags in conjunction with radar to identify the identity of enemy and friendly aircraft, and since then, the RFID system has gradually developed. Until the 1960s, the RFID system began to be applied in commercial activities, but the high price of the RFID tag limited the application scenarios of the RFID technology. With the development of time to the early 21st century, the cost of the RFID tag is getting lower and lower, and now the price of the RFID tag is 0.1 yuan per piece or even lower. With the reduction of production cost, the RFID system began to develop in a diversified direction.

[0004] The RFID tag is usually composed of a tag chip and a tag antenna. The relevant information of the identified object is stored in the tag chip, and the tag antenna is responsible for obtaining enough energy from the electromagnetic wave to make the tag chip enter the normal working state, complete the reception and transmission of the radio frequency signal, so that the RFID tag and even the RFID system can work normally. The tag can receive the electromagnetic wave transmitted by the RFID reader and complete the information exchange with the reader.

[0005] In the use process of the tag antenna, metal objects will inevitably be contacted, and these metal objects will have a great impact on the performance of the ordinary RFID tag antenna, causing the tag to be unable to be normally read, greatly limiting the use range and environment of the radio frequency identification technology. When the RFID tag antenna is attached to the metal surface, part of the signal emitted by the reader will be absorbed by the metal surface, causing the energy to be unable to meet the tag activation; another part of the signal is reflected by the metal surface, and the phase of the reflected signal is opposite to that of the incident wave, resulting in cancellation, causing the tag to lose energy and unable to work normally.

[0006] In practical applications, in order to meet different needs, the label needs to work on a variety of objects including metal. Therefore, many scholars at home and abroad have carried out research on the anti-metal electronic label. In recent years, the scheme of anti-metal label antenna has been put forward a lot, such as folding antenna, slot antenna, label antenna made of new materials. But the above scheme can only guarantee the performance of one side of the label antenna, and cannot make the label antenna have good anti-metal characteristics no matter how it is placed. SUMMARY

[0007] The purpose of the present application is to provide a rolling type anti-metal ultra-high frequency RFID label antenna, the frequency point offset of which is not more than the application frequency band when placed arbitrarily, and the RFID label antenna has good directivity and is suitable for application in the Internet of Things intelligent identification system.

[0008] The technical scheme of the present application is as follows: a rolling type anti-metal ultra-high frequency RFID label antenna, comprising two cylindrical insulating support members arranged coaxially at both sides, a plurality of radiation arms are arranged at intervals along the circumferential direction of the insulating support member, and the two ends of each radiation arm are tightly attached to the two insulating support members, a grounding arm is arranged between adjacent two radiation arms, one end of the radiation arm and the grounding arm is connected with a short-circuit wall, a chip is arranged between the two insulating support members, and the two ends of the chip are connected with a feed surface and a grounding surface through a guide piece, the feed surface is connected with the radiation arm, the grounding surface is connected with the grounding arm, or the feed surface is connected with the grounding arm, and the grounding surface is connected with the radiation arm.

[0009] Further, the total number of the radiation arms and the grounding arms can be 4-10, the number of arms connected with the feed surface is less than the total number of arms, and the number of arms connected with the grounding surface is equal to the total number of arms minus the number of arms connected with the radiation surface.

[0010] Further, the number of the radiation arms and the grounding arms is three respectively, and the radiation arms and the grounding arms are distributed on the circumferential surface of the insulating support member at an interval of 60°.

[0011] Further, the radiation arms and the grounding arms have the same structure, and the distance between the radiation arms and the adjacent grounding arms is equal.

[0012] Further, the insulating support member is a plastic sleeve, the radiation arms and the grounding arms are regular curved metal arms respectively, and the feed surface, the grounding surface, the guide piece and the short-circuit wall are made of metal material.

[0013] Further, the radiation arms, the grounding arms, the feed surface, the grounding surface, the guide piece and the short-circuit wall are made of brass or stainless steel.

[0014] Further, the material of the plastic sleeve is polytetrafluoroethylene.

[0015] Further, the width of the radiation arm and the ground arm is within 2mm-15mm; the length of the insulating support is 5mm-25mm, but the thickness is not fixed.

[0016] Further, the short-circuit wall is arranged at the outer side end of the insulating support on one side, and the distance between the insulating support on one side and the feeding surface is equal to the distance between the insulating support on the other side and the ground surface.

[0017] Further, the length of the radiation arm and the ground arm is the length corresponding to the quarter wavelength of the center frequency of the working frequency band of the antenna or an integer multiple thereof.

[0018] Compared with the prior art, the RFID tag antenna has the following advantages: the RFID tag antenna has a compact size of 12mm*12mm*65mm and a simple structure; the RFID tag antenna is covered by the application frequency band of the super high frequency RFID tag antenna in China, the frequency point offset when placed arbitrarily does not exceed the application frequency band, has good anti-metal characteristics, and ensures consistent use performance in various rolling states. Meanwhile, the antenna has good performance, good directivity, low manufacturing cost, and is suitable for application in the Internet of Things intelligent identification system. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 A perspective view of the embodiment of the present application Figure One ;

[0020] Figure 2 A perspective view of the embodiment of the present application Figure Two ;

[0021] Figure 3 A front view of the embodiment of the present application

[0022] Figure 4 A right view of the embodiment of the present application

[0023] Figure 5 Reflection coefficient simulation results of the surface of the embodiment 1 of the present application

[0024] Figure 6 Reflection coefficient simulation results of the surface of the embodiment 2 of the present application

[0025] Figure 7 Radiation pattern of the surface of the embodiment 1 of the present application in a metal environment

[0026] Figure 8 Radiation pattern of the surface of the embodiment 2 of the present application in a metal environment

[0027] In the diagram, 1-radiating arm; 2-grounding arm; 3-chip; 4-feeding surface; 5-grounding ground; 6-conducting plate; 7-insulating support; 8-short-circuit wall. Detailed Implementation

[0028] To make the above features and advantages of the present invention more readily understood, specific embodiments are described below in conjunction with the accompanying drawings, but the present invention is not limited thereto.

[0029] refer to Figures 1 to 8

[0030] A rolling, anti-metal UHF RFID tag antenna includes cylindrical insulating support members 7 located on both sides and coaxially arranged. Several radiating arms 1, each with its two ends tightly attached to two insulating support members, are spaced apart along the circumference of the insulating support members. A grounding arm 2 is located between adjacent radiating arms, and these grounding arms are also spaced apart along the circumference of the insulating support members, thus supporting the antenna through the two insulating support members. One end of each radiating arm and grounding arm is connected to a short-circuit wall 8. A chip 3 is located between the two insulating support members, with its two ends connected via guide plates 6 to a feed surface 4 and a ground surface 5, respectively. The guide plates are regular rectangles but their lengths are not fixed. The feed surface is connected to the radiating arm, and the ground surface is connected to the grounding arm, or vice versa. This tag antenna is symmetrical along its central axis and has rotational symmetry, ensuring that the symmetrical parts maintain the same performance during rolling.

[0031] In this embodiment, the total number of radiating arms and grounding arms can be 4-10, preferably an even number, to help reduce frequency shift during rotation. The number of arms connected to the feed surface is less than the total number of arms, and the number of arms connected to the ground surface is equal to the total number of arms minus the number of arms connected to the radiating surface.

[0032] Preferably, there are three radiating arms and three grounding arms, and the radiating arms and grounding arms are distributed on the circumferential surface of the insulating support at a 60° interval; the feeding surface and the grounding surface are both Y-shaped and are respectively connected to the corresponding grounding or radiating arm.

[0033] In this embodiment, the width of both the radiating arm and the grounding arm is within 2mm-15mm; both the radiating arm and the grounding arm are regular curved metal arms with good conductivity; the feeding surface, ground plane, conductive plate, and short-circuit wall are made of a metal material with good conductivity. Preferably, the radiating arm, grounding arm, feeding surface, ground plane, conductive plate, and short-circuit wall are made of brass or stainless steel, etc.

[0034] In this embodiment, the radiating arm and the grounding arm have the same structure, and the distance between the radiating arm and the adjacent grounding arm is equal, that is, the distance between the six metal arms is equal.

[0035] In this embodiment, the insulating support is a plastic sleeve made of an insulating material with good insulation properties. The length of the insulating support is 5mm-25mm, but the thickness is not fixed. Preferably, the plastic sleeve is made of polytetrafluoroethylene or similar materials.

[0036] In this embodiment, the short-circuit wall is disposed on the outer end of the insulating support on one side, and the distance between the insulating support on one side and the power supply surface is equal to that between the insulating support on the other side and the grounding surface.

[0037] In this embodiment, the lengths of the radiating arm and the grounding arm are the lengths corresponding to a quarter wavelength of the center frequency of the antenna's operating frequency band, or integer multiples thereof.

[0038] The above description is only a preferred embodiment of the present invention. For those skilled in the art, designing different forms of rolling anti-metal RFID tag antennas based on the teachings of the present invention does not require creative labor. All equivalent changes, modifications, substitutions and variations made in accordance with the scope of the patent application of the present invention without departing from the principles and spirit of the present invention shall be covered by the present invention.

Claims

1. A rolling anti-metal UHF RFID tag antenna, comprising cylindrical insulating support members located on both sides and coaxially arranged, characterized in that, Several radial arms, each with its two ends tightly attached to two insulating supports, are spaced apart along the circumference of the insulating support. A grounding arm is located between two adjacent radial arms. One end of each radial arm and grounding arm is connected to a short-circuit wall. A chip is located between two insulating supports. The two ends of the chip are connected to a feed surface and a ground surface via conductive plates. The feed surface is connected to the radial arm, and the ground surface is connected to the grounding arm, or the feed surface is connected to the grounding arm, and the ground surface is connected to the radial arm. The short-circuit wall is located on the outer end of one insulating support, and the distance between the insulating support on one side and the feed surface is equal to the distance between the insulating support on the other side and the ground surface.

2. The rolling anti-metal UHF RFID tag antenna according to claim 1, characterized in that, The total number of the radiating arms and grounding arms can be 4-10. The number of arms connected to the feed surface is less than the total number of arms, and the number of arms connected to the ground surface is equal to the total number of arms minus the number of arms connected to the radiating surface.

3. A rolling anti-metal UHF RFID tag antenna according to claim 1 or 2, characterized in that, The number of the radiating arms and the grounding arms are three each, and the radiating arms and the grounding arms are distributed on the circumferential surface of the insulating support at a 60° interval; the feeding surface and the grounding surface are both Y-shaped and are respectively connected to the corresponding grounding or radiating arms.

4. The rolling anti-metal UHF RFID tag antenna according to claim 3, characterized in that, The radial arm and the grounding arm have the same structure, and the distance between the radial arm and the adjacent grounding arm is equal.

5. A rolling anti-metal UHF RFID tag antenna according to claim 1, 2, or 4, characterized in that, The insulating support is a plastic sleeve, and the radiating arm and the grounding arm are regular curved metal arms; the feeding surface, the grounding surface, the conductive plate, and the short-circuit wall are made of metal materials.

6. A rolling anti-metal UHF RFID tag antenna according to claim 5, characterized in that, The radiating arm, grounding arm, feed surface, grounding surface, conductive plate, and short-circuit wall are made of brass or stainless steel.

7. A rolling anti-metal UHF RFID tag antenna according to claim 5, characterized in that, The plastic sleeve is made of polytetrafluoroethylene.

8. A rolling anti-metal UHF RFID tag antenna according to claim 5, characterized in that, The width of both the radiating arm and the grounding arm is between 2mm and 15mm; the length of the insulating support is between 5mm and 25mm, but the thickness is not fixed.

9. A rolling anti-metal UHF RFID tag antenna according to claim 1, characterized in that, The lengths of the radiating arm and the grounding arm are the lengths corresponding to a quarter wavelength of the center frequency of the antenna's operating frequency band, or integer multiples thereof.

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