Small-size low-cost wave velocity scanning antenna applied to UHF (Ultra High Frequency) band

Abstract

The invention discloses a small-size low-cost wave velocity scanning antenna applied to a UHF (Ultra High Frequency) band. The small-size low-cost wave velocity scanning antenna comprises a guide radiation unit, a nylon support column and an antenna main body, the guide radiation unit comprises a first substrate and four square metal radiation patches located at the top of the first substrate, and parasitic branches are adopted among the square metal radiation patches to improve the isolation degree and reduce the size of the antenna. The antenna body comprises a second substrate, a rectangular feeder line located on the lower side of the second substrate and four slot antenna units located on the upper side of the second substrate, the four slot antenna units adopt H-shaped slots, the antenna works in the UHF band by adjusting the size of the H-shaped slots, and the first substrate and the second substrate are both made of FR4 base material printed copper layers. The antenna is low in overall cost, miniaturization can be considered, beam scanning can be achieved, and beam radiation in different directions can be achieved through feeding of different antenna units.

Description

Technical Field

[0001] The invention belongs to the technical field of UHF communication technology, and in particular relates to a small-size, low-cost wave-speed scanning antenna applied to the UHF frequency band. Background Art

[0002] As an indispensable part of the UHF wireless system, the reader antenna is mainly responsible for sending and receiving electromagnetic wave signals in the wireless communication system.

[0003] As UHF technology is applied in more and more fields, the requirements in different scenarios are also different. When scanning tags in a larger range, a single antenna has a narrow beam and multi-sided antennas are expensive. A reader antenna that can achieve beam scanning can solve the above two problems. Therefore, it is meaningful to develop a low-cost, small-size reader antenna that can achieve beam scanning. Summary of the invention

[0004] The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art and provide a low overall cost and miniaturization, which can realize beam scanning, and different antenna unit feeding can realize beam radiation in different directions; the antenna adopts defect ground technology and parasitic branch technology respectively, which can ensure that the antenna units can achieve good decoupling in a relatively compact size, ensure the independence between the antenna units, and improve the isolation of the small size and low cost wave speed scanning antenna used in the UHF band.

[0005] The technical solution of the present invention to solve the above technical problems is as follows:

[0006] A small-size, low-cost wave-speed scanning antenna for use in the UHF frequency band comprises a directional radiation unit, a nylon support column and an antenna body; the directional radiation unit comprises a No. 1 substrate and four square metal radiation patches located on the top of the No. 1 substrate, parasitic branches are used between the square metal radiation patches to improve isolation and reduce the size of the antenna, the antenna body comprises a No. 2 substrate, a rectangular feed line located on the lower side of the No. 2 substrate and four slot antenna units located on the upper side of the No. 2 substrate, the four slot antenna units adopt "H"-shaped slots, and the antenna can work in the UHF frequency band by adjusting the size of the "H"-shaped slots, and the No. 1 substrate and the No. 2 substrate are both made of FR4 substrate printed copper layers.

[0007] Preferably, the slot antenna units are arranged orthogonally, and any two units are perpendicular to each other, which not only ensures the isolation between the units but also realizes four different radiation directions of the antenna.

[0008] Preferably, the rectangular feed line is located directly below the "H"-shaped gap and has a size of 2.8*45 mm to achieve better matching and radiation.

[0009] Preferably, the dimension of the "|" in the "H"-shaped slot is 1.3 * 43 mm, and the dimension of the "-" is 0.7 * 28 mm to achieve operation in the UHF band.

[0010] Preferably, decoupling between the four slot antenna elements is achieved through the cross-shaped defected ground technology, improving the isolation between the elements and realizing miniaturization of the antenna.

[0011] Preferably, when the width of the cross-shaped groove is 3.1 mm, the isolation between the slot antenna elements is optimal, and the radiation effect is also the best.

[0012] Preferably, the overall size of the wave velocity scanning antenna is 150 * 150 * 48.2 mm.

[0013] Preferably, the size of the square metal radiation patch is 68.5 mm, maintaining a high gain while keeping a small size; the distance between the square metal radiation patch and the slot antenna element is 45 mm, ensuring a low profile and high gain of the overall antenna.

[0014] Preferably, the square metal radiation patches adopt a cross shape with a "T"-shaped parasitic stub at the top to improve the isolation, and the width is 1 mm.

[0015] Preferably, the first substrate and the second substrate, as PCB boards, both adopt FR4 substrates with a size of 150 * 150 * 1.6 mm.

[0016] The antenna radiation unit of the present invention is made of a printed copper layer on an FR4 substrate, realizing low cost of the antenna and taking into account miniaturization; the overall antenna adopts a 2×2 array method to achieve beam scanning of the antenna, and different antenna elements can be fed to achieve beam radiation in different directions; the antenna adopts the defected ground technology and the parasitic stub technology respectively, which can ensure good decoupling of the antenna elements within a relatively compact size, ensure the independence between the antenna elements, and improve the isolation. Description of the Drawings

[0017] Figure 1 is a schematic three-dimensional structure diagram of the present invention;

[0018] Figure 2 is a schematic diagram of the director radiation unit in the present invention;

[0019] Figure 3 is a schematic diagram of the slot antenna element in the present invention

[0020] Figure 4 is a curve diagram of the return loss of the present invention;

[0021] Figure 5 is a curve diagram of the isolation between the units in the present invention;

[0022] Figure 6 are the 3D radiation patterns of the feeding beams of different antenna elements;

[0023] Wherein: 1. director radiation element, 2. parasitic stub, 3. nylon support column, 4. "H"-shaped slot, 5. "cross"-shaped defected ground, 6. rectangular feeder, 7. first substrate, 8. second substrate. Specific implementation manner

[0024] To make the objectives, technical effects and technical solutions of the embodiments of the present invention clearer, the following describes the technical solutions in the embodiments of the present invention clearly and completely with reference to the accompanying drawings in the embodiments of the present invention; obviously, the described embodiments are part of the embodiments of the present invention. Other embodiments obtained by those of ordinary skill in the art based on the disclosed embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0025] Embodiment 1

[0026] As Figure 1-6 shown, a small-size and low-cost beam scanning antenna applied to the UHF band includes a director radiation element 1, a nylon support column 3 and an antenna body; the director radiation element 1 includes a first substrate 7 and four square metal radiation patches located on the top of the first substrate 7. Parasitic stubs 2 are used between the square metal radiation patches to improve the isolation degree and reduce the antenna size. The antenna body includes a second substrate 8, a rectangular feeder 6 located on the lower side of the second substrate 8, and four slot antenna elements located on the upper side of the second substrate 8. The four slot antenna elements adopt "H"-shaped slots 4, and by adjusting the size of the "H"-shaped slots, the operation of the antenna in the UHF band is realized. Both the first substrate 7 and the second substrate 8 are made of FR4 substrate printed with a copper layer.

[0027] The slot antenna elements are arranged orthogonally, and are perpendicular to each other between two elements, which not only ensures the isolation degree between the elements, but also realizes four different radiation directions of the antenna.

[0028] The rectangular feeder 6 is located directly below the "H"-shaped slot 4, and its size is 2.8 * 45 mm to achieve better matching and radiation.

[0029] The "|" size of the "H"-shaped slot 4 is 1.3 * 43 mm, and the "-" size is 0.7 * 28 mm to realize the operation in the UHF band.

[0030] The decoupling between the four slot antenna elements is realized through the "cross"-shaped defected ground 5 technology to improve the isolation degree between the elements and realize the miniaturization of the antenna.

[0031] When the width of the "cross" groove is 3.1 mm, the isolation between the slot antenna units is optimal and the radiation effect is the best.

[0032] The overall size of the wave scanning antenna is 150*150*48.2mm.

[0033] The size of the square metal radiation patch is 68.5mm, which maintains a high gain while maintaining a smaller size; the distance between the square metal radiation patch and the slot antenna unit is 45mm, ensuring a lower profile and higher gain for the antenna as a whole.

[0034] The square metal radiation patches are arranged in a "cross" shape with a "T"-shaped parasitic branch at the top to improve isolation, with a width of 1mm.

[0035] Example 2

[0036] The first substrate 7 and the second substrate 8 are used as PCB boards, and both adopt FR4 substrates with a size of 150*150*1.6mm.

[0037] The antenna of the present invention has low overall cost and adopts FR4 substrate; it is small in size and includes four radiation units. By feeding different radiation units, beam radiation in different directions can be achieved.

[0038] As a part of the present invention, the illustrative embodiments of the present invention and their description are used to explain the present invention, but do not constitute improper limitations of the present invention.

Claims

1. A small-size, low-cost wave-speed scanning antenna for use in the UHF band, characterized by: The wave velocity scanning antenna includes a director radiation unit, a nylon support column, and an antenna body. The director radiation unit includes a first substrate and four square metal radiation patches located on the top of the first substrate. Parasitic stubs are used between the square metal radiation patches to improve isolation and reduce the antenna size. The antenna body includes a second substrate, a rectangular feeder located on the lower side of the second substrate, and four slot antenna units located on the upper side of the second substrate. The four slot antenna units use "H"-shaped slots. By adjusting the size of the "H"-shaped slots, the antenna operates in the UHF band. Both the first substrate and the second substrate are made of FR4 substrate printed with a copper layer.

2. A small-size, low-cost wave-speed scanning antenna for use in the UHF frequency band as claimed in claim 1, characterized in that: The slot antenna units are arranged orthogonally, perpendicular to each other in pairs, which not only ensures the isolation between the units but also realizes four different radiation directions of the antenna.

3. A small-size, low-cost wave-speed scanning antenna for use in the UHF band as claimed in claim 1, characterized in that: The rectangular feeder is located directly below the "H"-shaped slot, with a size of 2.8 * 45 mm to achieve better matching and radiation.

4. A small-size, low-cost wave-speed scanning antenna for use in the UHF band as claimed in claim 1, characterized in that: The "|" size of the "H"-shaped slot is 1.3 * 43 mm, and the "-" size is 0.7 * 28 mm to achieve operation in the UHF band.

5. A small-size, low-cost wave-speed scanning antenna for use in the UHF band as claimed in claim 1, characterized in that: Decoupling between the four slot antenna units is achieved through the "cross" defected ground technology to improve the isolation between the units and realize miniaturization of the antenna.

6. A small-size, low-cost wave-speed scanning antenna for use in the UHF band as claimed in claim 5, characterized in that: When the width of the "cross" groove is 3.1 mm, the isolation between the slot antenna units is optimal, and the radiation effect is the best.

7. A small-size, low-cost, wave-speed scanning antenna for use in the UHF band as claimed in claim 1, characterized in that: The overall size of the wave velocity scanning antenna is 150 * 150 * 48.2 mm.

8. The small-size, low-cost wave-speed scanning antenna for use in the UHF band as claimed in claim 1, characterized in that: The size of the square metal radiation patch is 68.5 mm, which maintains a high gain while keeping the size small. The distance between the square metal radiation patch and the slot antenna unit is 45 mm, ensuring a low profile and high gain of the overall antenna.

9. A small-size, low-cost wave-speed scanning antenna for use in the UHF band as claimed in claim 1, characterized in that: "Cross" and "T"-shaped parasitic stubs are used between the square metal radiation patches to improve isolation, with a width of 1 mm.

10. The small-size, low-cost wave-speed scanning antenna for use in the UHF band as claimed in claim 1, characterized in that: Both the first substrate and the second substrate, as PCB boards, use FR4 substrates with a size of 150 * 150 * 1.6 mm.

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