A low profile wideband antenna for 5G-WiFi frequency band

Abstract

The application discloses a low-profile wideband antenna for a 5G-WiFi frequency band. The low-profile wideband antenna comprises a dielectric substrate and a metal radiation layer arranged on the upper surface of the dielectric substrate. The metal radiation layer comprises a rectangular patch and two identical U-shaped patches, and the two identical U-shaped metal patches are arranged close to the radiation edge and the non-radiation edge of the rectangular patch at the same time, so as to surround the rectangular patch. Two longitudinal metal slots are loaded on the rectangular patch, and a horizontal line rectangular slot is arranged to enhance the bandwidth of the antenna. The low-profile wideband antenna can ensure that the antenna has a low antenna profile and has sufficient bandwidth to cover WLAN 5.2GHz (5.15-5.36GHz), WLAN 5.8GHz (5.725-5.825GHz) and WiMAX 5.5 (5.25-5.825GHz).

Description

Technical Field

[0001] The present invention belongs to the technical field of microstrip antennas, and in particular relates to a low-profile broadband antenna for the 5G-WiFi frequency band. Background Art

[0002] 5G Wi-Fi (i.e., the 802.11ac and 802.11ax standards) operates in the 5 GHz band, providing higher data rates and improved network performance. The 5 GHz band offers a wider available bandwidth, supporting multiple non-overlapping channels, thereby reducing interference and increasing network capacity. With the increasing popularity of applications such as smart homes, the Internet of Things (IoT), high-definition video streaming, and virtual reality (VR), the demand for antennas designed for the 5G Wi-Fi band is increasing.

[0003] Broadband antennas can provide good performance across a wide frequency range, which is particularly important for 5G Wi-Fi. The 5G Wi-Fi frequency band has a wide available bandwidth, from 5.150 GHz to 5.850 GHz, covering multiple sub-bands such as WLAN 5.2 GHz (5.15-5.36 GHz), WLAN 5.8 GHz (5.725-5.825 GHz), and WiMAX 5.5 (5.25-5.825 GHz). Broadband antennas can cover all frequency bands within this range, providing greater flexibility and compatibility. Traditional microstrip antennas are favored by antenna researchers due to their small size, low profile, low price, and ease of integration. However, this low profile and small size also come with a narrow bandwidth, which is an inherent drawback. Designing a broadband antenna that meets design requirements while maintaining the advantages of microstrip antennas' low profile has become a research challenge. Summary of the Invention

[0004] The purpose of the present invention is to overcome the shortcomings of the existing technology and propose a low-profile broadband antenna for the 5G-WiFi frequency band. While ensuring a low antenna profile, the antenna has sufficient bandwidth to cover the WLAN 5.2GHz (5.15-5.36GHz), WLAN 5.8GHz (5.725-5.825GHz) and WiMAX 5.5 (5.25-5.825GHz) frequency bands.

[0005] The present invention is achieved through the following technical solutions:

[0006] A low-profile broadband antenna for the 5G-WiFi frequency band comprises a dielectric substrate and a metal radiating layer disposed on the upper surface of the dielectric substrate. The metal radiating layer comprises a rectangular patch and two identical U-shaped patches, wherein the rectangular patch is positioned at the center of the dielectric substrate, and the two U-shaped patches are symmetrically disposed on either side of the rectangular patch, adjacent to both the radiating and non-radiating edges of the rectangular patch, thereby surrounding the rectangular patch. The rectangular patch is loaded with two longitudinal rectangular slots and one transverse rectangular slot to enhance the antenna bandwidth. The transverse rectangular slot is positioned at the center of the rectangular patch, and the two longitudinal rectangular slots are centrally symmetrically distributed about the center point of the rectangular patch, with their outer ends extending to the side edges of the rectangular patch.

[0007] Furthermore, the dielectric substrate is FR4, whose relative dielectric constant, loss tangent, length and width are all 35 mm, and thickness is 1.585 mm.

[0008] Furthermore, the metal radiation patch on the upper surface of the dielectric substrate, namely the central rectangular patch with two longitudinal rectangular gaps and one transverse rectangular gap and two identical U-shaped patches, are all copper-clad, with a thickness of 0.035 mm.

[0009] The rectangular patch has a length of L = 16.5 mm and a width of W = 11.8 mm. Two identical longitudinal rectangular slits are inserted into the patch, each 5.46 mm long and 0.12 mm wide, located 2.70 mm from the antenna's center axis. A transverse rectangular slit is inserted into the patch, 2.73 mm long and 0.25 mm wide, with the midpoint of its diagonal coinciding with the center of the antenna.

[0010] Furthermore, the U-shaped patch consists of a long rectangle and two identical short rectangles, wherein the long rectangle is 33 mm long and 7 mm wide; the short rectangle is 6.6 mm long and 6.3 mm wide; and the distance between the short rectangle and the outer edge of the long rectangle is 0.5 mm.

[0011] Furthermore, a coaxial feeding method is adopted, the radius of the coaxial inner core is 0.3 mm, and the radius of the outer core is 1.29 mm; the feeding position is 5 mm directly below the symmetry center of the antenna.

[0012] The beneficial effects of the present invention are as follows: the present invention designs a low-profile broadband antenna for the 5G-WiFi frequency band based on the microstrip antenna theory. The central rectangular patch provides a low-frequency resonance point, and the two C-shaped patches provide a high-frequency resonance point. By adjusting the coupling gap between the C-shaped patch and the rectangular patch, two longitudinal rectangular gaps and one transverse rectangular gap are loaded on the central rectangular patch to adjust the spacing between the two resonance points and expand the bandwidth. This allows the antenna to have sufficient bandwidth to cover the WLAN5.2GHz (5.15-5.36GHz), WLAN5.8GHz (5.725-5.825GHz) and WiMAX5.5 (5.25-5.825GHz) frequency bands while ensuring a lower antenna profile. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 Schematic diagram of the three-dimensional structure of an embodiment of the present invention.

[0014] Figure 2 2 is a top view of an embodiment of the present invention.

[0015] Figure 3 This is step 1 of the embodiment of the present invention.

[0016] Figure 4 FIG. 1 is a diagram of the reflection coefficient S11 in step 1 of an embodiment of the present invention.

[0017] Figure 5 This is step 2 of the embodiment of the present invention.

[0018] Figure 6 This is a reflection coefficient S11 diagram of step 2 of an embodiment of the present invention.

[0019] Figure 7 Graph showing the reflection coefficient S11 according to an embodiment of the present invention.

[0020] Figure 8 : is the radiation pattern of an embodiment of the present invention at 5.12 GHz.

[0021] Figure 9 : is the radiation pattern of an embodiment of the present invention at 5.70 GHz. DETAILED DESCRIPTION

[0022] The technical solution of the present invention is described in detail below in conjunction with the drawings in the technical specification, but the protection scope of the present invention is not limited to the following.

[0023] like Figure 1-2 As shown, an embodiment of the present invention provides a low-profile broadband antenna for the 5G-WiFi frequency band, comprising: a dielectric substrate (1) and a metal radiation layer (2) arranged on the dielectric substrate.

[0024] The metal radiation layer comprises a rectangular patch (3) and two identical U-shaped patches (4).

[0025] The rectangular patch (3) is located at the center of the dielectric substrate (1), and is loaded with two longitudinal rectangular slots (5) and one transverse rectangular slot. The two rectangular slots are located at the lower left and upper right of the center of the antenna, respectively, and are symmetrically distributed about the center of the antenna. The transverse rectangular slot is located at the center of the antenna, and the midpoint of its diagonal coincides with the center of the antenna.

[0026] The U-shaped patch (4) is composed of a long rectangle (8) and two identical short rectangles (7). The two identical U-shaped patches (4) are respectively located directly above and directly below the rectangular patch and are axially symmetrically distributed about the center of the antenna.

[0027] The low-profile broadband antenna for the 5G-WiFi frequency band adopts a coaxial feeding method. The coaxial feeding point is located 5 mm below the center of the antenna. The coaxial is directly welded on the rectangular patch (3). The inductance of the coaxial is used to offset the capacitive characteristics generated by the two rectangular gaps on the rectangular patch.

[0028] The design concept of the embodiment of the present invention is as follows: a rectangular patch (3) at the center of the antenna provides a low-frequency resonance point, and two U-shaped patches (4) provide a high-frequency resonance point. At the same time, the coupling gaps between the rectangular patch (3) and the U-shaped patch (4) are adjusted, and two longitudinal rectangular slots (5) and one transverse rectangular slot (6) are added to the rectangular patch (3), so that the antenna bandwidth meets the design requirements and covers the 5G Wi-Fi frequency band. The technical effects of the present invention are described in detail below with reference to the accompanying drawings.

[0029] ]like Figure 3 As shown in FIG. 1 , the embodiment of the present invention provides a low-frequency resonance point by the central rectangular patch (3). The present invention targets the 5G-WiFi frequency band, and the low-frequency resonance point is expected to be set between 5.0 GHz and 5.2 GHz. According to the microstrip antenna theory, the length of the central rectangular patch is L = 16.5 mm and the width is W = 11.8 mm. The reflection coefficient S11 of step 1 is shown in FIG. Figure 4 shown.

[0030] like Figure 5As shown, step 2 of the embodiment of the present invention: two identical U-shaped patches (4) and a central rectangular patch (3) are coupled to generate a high-frequency resonance point. After design and debugging, the coupling patch part is finally designed to be U-shaped, consisting of a long rectangle and two identical short rectangles. The long rectangle is 33mm long and 7mm wide; the short rectangle (7) is 6.6mm long and 6.3mm wide. The distance between the short rectangle (7) and the outer edge of the long rectangle is 0.5mm. The coupling width of the U-shaped patch (4) and the central rectangular patch (3) in the vertical direction is 1.3mm, and the coupling width in the left and right direction is 1.1mm. The reflection coefficient S11 of step 2 is shown in FIG. Figure 6 shown.

[0031] like Figure 2 As shown, step three of the embodiment of the present invention is to load two longitudinal rectangular slots (5) and one transverse rectangular slot (6) on the central rectangular patch (3), adjust the distance between the two resonance points, and enhance the bandwidth so that the antenna bandwidth can meet the design requirements and cover the 5G-WiFi frequency band. At this point, the design of the embodiment of the present invention is completed. The final reflection coefficient S11 of the embodiment of the present invention is shown in FIG. Figure 8 As shown, it can be seen that the reflection coefficients of the low-frequency resonance point at 5.12 GHz and the high-frequency resonance point at 5.70 GHz are both lower than -20, indicating good matching.

[0032] like Figure 8-9 As shown in the figure, the radiation patterns of the low-profile broadband antenna for the 5G-WiFi frequency band provided by the embodiment of the present invention operating at 5.12 GHz and 5.70 GHz respectively, it can be seen that the antenna pattern is stable, the difference between the main polarization and the cross polarization is greater than 20 dB, and the performance is good.

[0033] The descriptions of "upper," "lower," "left," and "right" in the embodiments of the present invention are intended solely to describe the present invention and simplify the description. They are not to be construed as indicating or implying that a device or component must have, be constructed, or operate in a specific orientation. Therefore, they are not to be construed as limiting the present invention. Furthermore, the terms "longitudinal" and "transverse" are intended solely to describe perspective and are not to be construed as indicating or implying relative importance.

[0034] The foregoing description is a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the form disclosed herein and should not be construed as excluding other embodiments. Instead, the present invention can be used in other combinations, modifications, and environments and can be modified within the scope of the concept described herein through the above teachings or techniques or knowledge in the relevant field. Modifications and variations made by those skilled in the art that do not depart from the spirit and scope of the present invention are intended to be protected by the appended claims.

Claims

1. A low-profile broadband antenna for the 5G-WiFi frequency band, characterized by: The antenna comprises a dielectric substrate (1) and a metal radiation patch (2) arranged on the upper surface of the dielectric substrate (1); the metal radiation layer (2) comprises a rectangular patch (3) and two identical U-shaped patches (4), wherein the rectangular patch (3) is placed at the center of the dielectric substrate (1), and the two U-shaped patches (4) are symmetrically arranged on both sides of the rectangular patch (3) and are adjacent to the radiation side and the non-radiation side of the rectangular patch (3) at the same time, surrounding the rectangular patch (3); two longitudinal rectangular slots (5) and one transverse rectangular slot (6) are loaded on the rectangular patch (3) for enhancing the antenna bandwidth, wherein the transverse rectangular slot (6) is placed at the center of the rectangular patch (3), and the two longitudinal rectangular slots (5) are centrally symmetrically distributed about the center point of the rectangular patch (3), and the outer ends extend to the side edges of the rectangular patch (3) respectively.

2. The low-profile broadband antenna for the 5G-WiFi frequency band according to claim 1, characterized in that: The dielectric substrate (1) is FR4, which has a relative dielectric constant, loss tangent, a length and a width of 35 mm, and a thickness of 1.585 mm.

3. The low-profile broadband antenna for the 5G-WiFi frequency band according to claim 1, characterized in that: The metal radiation patch (2) located on the upper surface of the dielectric substrate (1), i.e., the central rectangular patch (3) loaded with two longitudinal rectangular gaps (5) and one transverse rectangular gap (6) and two identical U-shaped patches are all copper-clad, and the thickness is 0.035 mm.

4. The low-profile broadband antenna for the 5G-WiFi frequency band according to claim 1, characterized in that: The rectangular patch (3) has a length of L = 16.5 mm and a width of W = 11.8 mm.

5. The low-profile broadband antenna for the 5G-WiFi frequency band according to claim 1, characterized in that: Two identical longitudinal rectangular slits (5) are loaded on the rectangular patch (3), with a length of 5.46 mm, a width of 0.12 mm, and a distance of 2.70 mm from the center axis of the antenna.

6. The low-profile broadband antenna for the 5G-WiFi frequency band according to claim 1, characterized in that: A transverse rectangular gap (6) is loaded on the rectangular patch (3), with a length of 2.73 mm and a width of 0.25 mm, and the midpoint of the diagonal thereof coincides with the center of the antenna.

7. The low-profile broadband antenna for the 5G-WiFi frequency band according to claim 1, characterized in that: The U-shaped patch (4) consists of a long rectangle (8) and two identical short rectangles (7), wherein the long rectangle is 33 mm long and 7 mm wide; the short rectangle (7) is 6.6 mm long and 6.3 mm wide; and the distance between the short rectangle (7) and the outer edge of the long rectangle is 0.5 mm.

8. The low-profile broadband antenna for the 5G-WiFi frequency band according to claim 1, characterized in that: Coaxial feeding is adopted, the coaxial inner core radius is 0.3mm, and the outer core radius is 1.29mm; the feeding position is 5mm directly below the symmetry center of the antenna.

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