Radio frequency identification antenna structure
By designing a radio frequency identification antenna structure including inductance coil and dipole antenna, the problem that RFID tags are not readable in dense stacking environments is solved, and efficient reading performance and communication capabilities are achieved in complex environments.
Patent Information
- Application Number
- CN202422084207.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-26
- Publication Date
- 2025-06-06
- Estimated Expiration
- 2034-08-26
AI Technical Summary
Existing RFID tags are not readable in dense stacking environments, resulting in increased read difficulty.
A radio frequency identification antenna structure is designed, including an inductor coil and a symmetrical dipole antenna, forming a rectangular metal sheet with an integrated structure, with a T-shaped groove and chip contacts in the middle, and dipole antennas are on both sides of the T-shaped groove, and T-shaped holes are opened on the dipole antenna to improve communication capabilities.
This RF antenna structure is used in complex environments and is especially suitable for intensive reading scenarios of multiple RFID tags, which significantly improves the reading performance and communication capabilities of RFID tags.
Smart Images
Figure CN222953362U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of radio frequency RFID tags, and in particular relates to a radio frequency identification antenna structure. Background Art
[0002] RFID technology is a widely used automatic identification method. Applying RFID technology in different industries can realize real-time dynamic tracking and query of the supply chain, and provide enterprises with real and effective management data, thereby improving work efficiency, reducing human resource costs, and reducing capital costs.
[0003] In practical applications, RFID tags are often used in scenarios where intensive reading is required. Figure 7 When the RF antenna structure is shown, the smaller the spacing between RFID tags, the more difficult it is to read. Therefore, it is necessary to design suitable RFID tags for densely stacked scenarios. Utility Model Content
[0004] The technical problem to be solved by the utility model is to overcome the deficiencies of the prior art and provide a radio frequency identification antenna structure for solving the technical problem that the existing RFID tags are not easily read in a densely stacked environment.
[0005] The utility model solves the above technical problems with the following technical solutions: a radio frequency identification antenna structure, comprising an inductor coil and a pair of symmetrical dipole antennas, wherein the inductor coil and the dipole antenna are a rectangular metal sheet with an integrated structure;
[0006] A vertical T-shaped slot is provided in the middle of the metal sheet, a symmetrical chip contact is provided in the middle of the vertical section of the T-shaped slot, and the range from the horizontal section of the T-shaped slot to the chip contact is the inductor coil;
[0007] Both sides of the T-slot are dipole antennas.
[0008] The utility model adopts a large-area metal area design, without a complex reciprocating bending radiation arm design, and adopts a large-area metal covering design. The radar scattering cross-section is large, the backscattering energy is strong, and the reader receives strong energy reflected by the RFID tag. It is suitable for being attached to objects with different dielectric constants and can be used in complex environments. It is especially suitable for dense reading scenarios with multiple RFID tags (more than 20 RFID tags) spaced apart (the RFID tag spacing can be less than 3cm).
[0009] Furthermore: each of the dipole antennas is provided with a horizontal T-shaped hole.
[0010] The beneficial effect of adopting this step is that the communication capability of the radio frequency antenna can be improved.
[0011] Furthermore: the horizontal section of the T-shaped hole is divided into two sections, one section is a single slit hole, and the other section is a short T hole.
[0012] The beneficial effect of adopting this step is that the communication capability of the radio frequency antenna can be further improved.
[0013] Furthermore: the width of the T-shaped hole is 1 / 4 to 3 / 4 of the total width of the RFID antenna structure; the length of the T-shaped hole is 1 / 16 to 2 / 5 of the total length of the RFID antenna structure.
[0014] The beneficial effect of adopting this step is that the shape and size of the T-shaped hole can affect the operating frequency width range of the radio frequency antenna.
[0015] Furthermore, the distance between the short T hole and the single slit hole is 1 mm to 12 mm.
[0016] The beneficial effect of adopting this step is that the distance between the two can also affect the width range of the operating frequency.
[0017] Furthermore: the opening of the T-slot is a spliced shape of an inverted triangle and a rectangle, wherein the inverted triangle is close to the chip contact.
[0018] The beneficial effect of adopting this step is that this splicing shape can adjust the antenna impedance and make the antenna reach the best matching state.
[0019] The beneficial effects of the utility model are:
[0020] 1. The utility model is a UHF radio frequency antenna design structure, which is composed of an inductor coil and a dipole antenna part. It adopts an integrated coupling method of the inductor coil and the dipole antenna, and is suitable for being attached to objects with different dielectric constants and can be used in complex environments;
[0021] 2. The antenna design structure is suitable for dense group reading scenarios with multiple RFID tags (more than 20 tags) at close distances (less than 3cm spacing). BRIEF DESCRIPTION OF THE DRAWINGS
[0022] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0023] Figure 1 This is a structural schematic diagram of Embodiment 3 of a radio frequency identification antenna structure provided by the utility model;
[0024] Figure 2 A structural schematic diagram and HFSS simulation diagram of a first embodiment of a radio frequency identification antenna structure provided by the utility model;
[0025] Figure 3 A structural schematic diagram and HFSS simulation diagram of a second embodiment of a radio frequency identification antenna structure provided by the utility model;
[0026] Figure 4 A structural schematic diagram and HFSS simulation diagram of Embodiment 3 of a radio frequency identification antenna structure provided by the utility model;
[0027] Figure 5 It is a simulation performance diagram of the first embodiment, the second embodiment and the third embodiment of the radio frequency identification antenna structure provided by the utility model;
[0028] Figure 6 A frequency sweeping performance diagram of a third embodiment of a radio frequency identification antenna structure provided by the utility model and a radio frequency identification antenna in the prior art;
[0029] Figure 7 It is a structural schematic diagram of a radio frequency identification antenna structure in the prior art.
[0030] Reference numerals:
[0031] 1- inductor coil; 2- dipole antenna; 3- chip contact;
[0032] 21- short T hole; 22- single slit hole. DETAILED DESCRIPTION
[0033] The following embodiments of the technical solution of the utility model are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the utility model, and are therefore only used as examples, and cannot be used to limit the protection scope of the utility model.
[0034] It should be noted that, unless otherwise specified, the technical terms or scientific terms used in the present invention should have the common meanings understood by technicians in the field to which the present invention belongs.
[0035] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.
[0036] In addition, the terms "first", "second", etc. are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. In the description of the present utility model, the meaning of "plurality" is more than two, unless otherwise clearly and specifically limited.
[0037] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.
[0038] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.
[0039] Example
[0040] like Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown, the first embodiment of a radio frequency identification antenna structure provided by the utility model comprises an inductor 1 and a pair of symmetrical dipole antennas 2, wherein the inductor 1 and the dipole antenna 2 are rectangular metal sheets of an integral structure;
[0041] A vertical T-shaped slot is provided in the middle of the metal sheet, a symmetrical chip contact 3 is provided in the middle of the vertical section of the T-shaped slot, and the range from the horizontal section of the T-shaped slot to the chip contact 3 is the inductor 1 ( Figure 1 The white box in the middle only indicates the range of the inductor 1, and is not the structure of the present invention. The inductor 1 is designed to be similar to a rectangle, and the impedance matching is adjusted by adjusting the size and shape of the inductor similar to a rectangle. ;
[0042] Both sides of the T-slot are the dipole antennas 2, and the inductor coil 1 and the dipole antenna 2 are integrally coupled. The inductor coil 1 and the dipole antenna 2 overlap in a large area, and this design form is less affected by the dielectric constant of the external back sticker.
[0043] The utility model adopts a large-area metal area design, without a complex reciprocating bending radiation arm design, and adopts a large-area metal covering design. The radar scattering cross-section is large, the backscattering energy is strong, and the reader receives strong energy reflected by the RFID tag. It is suitable for being attached to objects with different dielectric constants and can be used in complex environments. It is especially suitable for dense reading scenarios with multiple RFID tags (more than 20 RFID tags) spaced apart (the RFID tag spacing can be less than 3cm).
[0044] Based on the above technical solution, a second embodiment is provided, wherein each of the dipole antennas 2 is provided with a horizontal T-shaped hole, which can enhance the communication capability of the radio frequency antenna.
[0045] Based on the above technical solution, a third embodiment is provided, in which the horizontal section of the T-shaped hole is divided into two sections, one section is a single slot hole 22, and the other section is a short T-hole 21. The communication capability of the radio frequency antenna can be further improved.
[0046] like Figure 2 , Figure 3 , Figure 4 and Figure 5 As shown, the HFSS simulation result of the first embodiment shows that the gain at the frequency point of 920 MHz is 1.42 dBm; the HFSS simulation result of the second embodiment shows that the gain at the frequency point of 920 MHz is 1.68 dBm; the HFSS simulation result of the third embodiment shows that the gain at the frequency point of 920 MHz is 1.76 dBm; Figure 5 It is a frequency-gain diagram. According to the gain variation trend, the top oblique line in the diagram is embodiment 3, the middle oblique line is embodiment 2, and the bottom oblique line is embodiment 1. It can be judged that the communication effect of embodiment 3 is better.
[0047] The width of the T-shaped hole is 1 / 4 to 3 / 4 of the total width of the RFID antenna structure; and the length of the T-shaped hole is 1 / 16 to 2 / 5 of the total length of the RFID antenna structure.
[0048] The shape and size of the T-hole can affect the operating frequency width range of the RF antenna.
[0049] Wherein, the distance between the short T hole 21 and the single slit hole 22 is 1 mm to 12 mm.
[0050] The distance between the two can also affect the width of the operating frequency range.
[0051] On the basis of the above technical solution, the opening of the T-slot is a combined shape of an inverted triangle and a rectangle, wherein the inverted triangle is close to the chip contact 3 .
[0052] This splicing shape can adjust the antenna impedance so that the antenna reaches the best matching state.
[0053] Finally, if Figure 6 As shown, a scanning comparison of the group reading effect (the scanning curve shows the reading performance of the middle RFID tag) of the wound dipole linear antenna of the prior art and the antenna of the utility model in a dense group reading scenario of more than 20 RFID tags (the two RFID tags have basically the same external dimensions and the same test scenario): the scanning results (the light-colored broken line is the present application, and the dark-colored broken line is the prior art) show that when the two are of similar size, at 980MHz, the reading distance of the RF antenna of the prior art is 2.9m, and the reading distance of the RF antenna of the utility model can reach 5.8m. The use of the utility model can significantly improve the RFID tag performance in a dense reading scenario of multiple RFID tags (more than 20 RFID tags), especially the reading performance in the 960-1100MHz frequency band.
[0054] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not make the essence of the corresponding technical solution deviate from the scope of the technical solution of the embodiments of the utility model.
Claims
1. A radio frequency identification antenna structure, characterized in that: It includes an inductor and a pair of symmetrical dipole antennas, wherein the inductor and the dipole antenna are rectangular metal sheets with an integrated structure; A vertical T-shaped slot is provided in the middle of the metal sheet, a symmetrical chip contact is provided in the middle of the vertical section of the T-shaped slot, and the range from the horizontal section of the T-shaped slot to the chip contact is the inductor coil; Both sides of the T-slot are dipole antennas.
2. The RFID antenna structure according to claim 1, characterized in that: Each of the dipole antennas is provided with a horizontal T-shaped hole.
3. The RFID antenna structure according to claim 2, characterized in that: The horizontal section of the T-shaped hole is divided into two sections, one section is a single slit hole, and the other section is a short T hole.
4. The RFID antenna structure according to claim 2 or 3, characterized in that: The width of the T-shaped hole is 1 / 4 to 3 / 4 of the total width of the RFID antenna structure; the length of the T-shaped hole is 1 / 16 to 2 / 5 of the total length of the RFID antenna structure.
5. The RFID antenna structure according to claim 3, characterized in that: The distance between the short T hole and the single slit hole is 1 mm to 12 mm.
6. The RFID antenna structure according to claim 1, characterized in that: The opening of the T-shaped slot is in the shape of a combination of an inverted triangle and a rectangle, wherein the inverted triangle is close to the chip contact.