Dual-frequency dual-ring planar slot antenna applied to WLAN (Wireless Local Area Network)

Abstract

The invention discloses a dual-frequency dual-ring planar slot antenna applied to a WLAN (Wireless Local Area Network). The dual-frequency dual-ring planar slot antenna comprises a dielectric substrate and a planar metal sheet, the planar metal sheet is printed on the surface of the dielectric substrate, a long gap is horizontally formed in the middle of the planar metal sheet, a small annular gap and a large annular gap are formed in the planar metal sheet at intervals from inside to outside with the center of the long gap as the center of a circle, and a feeding point is arranged at the position, close to the center, of the long gap. According to the invention, the dual-band design requirement of the WLAN is realized through slotting modes in different forms, and the frequency coverage is 2400-2500MHz amp; and the antenna has relatively good port impedance, so that the wide impedance bandwidth of the antenna can be realized. The antenna is good in performance, easy to process and easy to install and conform.

Description

Technical Field

[0001] The present invention relates to the technical field of slot antennas, and in particular to a dual-band dual-ring planar slot antenna applied to WLAN. Background Art

[0002] At present, wireless communication technologies such as wireless LAN and point-to-point microwave communication services are developing at a rapid pace, which has led to an increasing demand for antennas that are compatible with them. Such antennas generally require low cost, easy manufacturing, and easy installation and adjustment. The use of small planar antennas is not only easy to install, but also easy to conceal or decorate. At the same time, the use of planar slot antennas can also easily achieve beam adjustability to achieve coverage of specific areas in the room, thereby reducing electromagnetic radiation, improving radiation efficiency, and avoiding electromagnetic damage. The slot planar antenna is a typical planar antenna that just caters to the development trend and requirements of modern wireless communication systems and has received widespread attention and research. The slot antenna is a kind of aperture antenna formed by opening a slot on a metal plate, waveguide, coaxial line or resonant cavity, and electromagnetic waves radiate to the outside through the slot. Its biggest feature is low profile, good flat-mount structure, and easy conformity with the installation object. At the same time, the slot antenna also has the advantages of firm structure, simple and compact, easy processing, economical cost, convenient feeding, simple installation, concealability, and decoratability.

[0003] Slot antennas have found widespread use in many areas of the communications industry. However, unlike monopole and PIFA antennas, they are rarely seen in the design of mobile terminals. One possible reason for this is that the modes that excite a slot antenna are usually not simple, including both fundamental and higher-order modes. In addition, it is often more difficult to develop methods to adjust the frequency ratio of the excited fundamental and higher modes of a slot antenna, which is often required to achieve broadband and multi-band operation of mobile terminals, compared to monopole or PIFA antennas. However, slot antennas have a very limited bandwidth because only odd modes are excited using a high-impedance source input at the center of the slot. Summary of the invention

[0004] The object of the present invention is to provide a dual-band dual-circular planar slot antenna for WLAN, which is applied to terminal equipment of WLAN local area network, can achieve the requirements of dual-band and wide bandwidth, has a low profile, and is easy to install conformally.

[0005] The technical solution adopted by the present invention is: A dual-band dual-circular planar slot antenna for WLAN comprises a dielectric substrate and a planar metal sheet; the planar metal sheet is printed on the surface of the dielectric substrate, a long slot is horizontally opened in the middle of the planar metal sheet, and a small circular slot and a large circular slot are spaced from the inside to the outside on the planar metal sheet with the center of the long slot as the center point, and a feeding point is arranged near the center of the long slot.

[0006] Specifically, a large circular gap is opened on the plane metal sheet with the center of the long gap as the center point, and a feeding point is set near the center of the long gap to achieve a frequency range of 2400-2500MHz in the WLAN frequency band; and a small circular gap is opened on the plane metal sheet with the center of the long gap as the center point, and the radius of the small circular gap is smaller than that of the large circular gap, that is, the small circular gap is located inside the circle formed by the large circular gap to achieve resonance in the 5150-5850MHz frequency band.

[0007] Furthermore, the dielectric substrate is a FR4 dielectric substrate.

[0008] Furthermore, the large annular gap and the small annular gap are connected via a connecting gap.

[0009] Furthermore, there are two connecting gaps, which are located in the half area or the lower half area of ​​the plane metal sheet separated by the long gap, and the two connecting gaps are axially symmetrically arranged with a vertical line passing through the center of the long gap as the symmetry axis.

[0010] Furthermore, two symmetrical and independent integral structure gaps are respectively provided inside the circle formed by the small circular annular gap with the horizontal central axis of the long gap as the symmetry axis. That is, the long gap divides the small circular annular gap into two semicircles, and an independent integral structure gap is provided in the two semicircles; the two independent integral structure gaps are axially symmetrically arranged with the long gap as the symmetry axis.

[0011] Furthermore, the integrated structural gap includes two horizontal gaps and three vertical gaps. The two horizontal gaps are arranged at intervals and are parallel to the horizontal center axis of the long gap. The three vertical gaps are arranged at intervals between the two horizontal gaps. The two ends of the three vertical gaps are respectively connected to the horizontal gaps at the corresponding ends.

[0012] Furthermore, the length of a horizontal slit far from the elongated slit is greater than the length of another horizontal slit close to the elongated slit.

[0013] The present invention is used to widen the bandwidth of 5150-5850 MHz in the WLAN frequency band by opening these gaps, thereby achieving the design requirements within the frequency range of 5150-5850 MHz.

[0014] The present invention adopts the above technical solution and has the following advantages: the WLAN dual-band design requirements are realized through different forms of slots, the frequency covers 2400-2500MHz & 5150-5850MHz, the antenna has good port impedance, and the antenna wide impedance bandwidth can be achieved. The antenna has good performance, is easy to process, and is easy to install conformally. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments; Figure 1 This is a schematic structural diagram of a dual-band dual-ring planar slot antenna applied to WLAN in the present invention; Figure 2 It is an enlarged schematic diagram of a slot structure applied to a WLAN dual-band dual-ring planar slot antenna according to the present invention; Figure 3 It is a schematic diagram of the antenna standing wave ratio (VSWR) of the present invention in the frequency band of 2400-2500MHz; Figure 4 It is a schematic diagram of the antenna standing wave ratio (VSWR) of the present invention in the frequency band of 5150-5850MHz. Implementation

[0016] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application.

[0017] like Figures 1 to 4 As shown in one, the present invention discloses a dual-band dual-circular planar slot antenna for WLAN, comprising a dielectric substrate 1 and a planar metal sheet 2; the planar metal sheet 2 is printed on the surface of the dielectric substrate 1, a long slot 3 is horizontally opened in the middle position of the planar metal sheet 2, and a small circular slot 5 and a large circular slot 4 are spaced from the inside to the outside on the planar metal sheet 2 with the center of the long slot 3 as the center point of the circle, and a feeding point is set near the center position of the long slot 3.

[0018] Specifically, a large circular ring-shaped gap 4 is opened on the planar metal sheet 2 with the center of the long gap 3 as the center point, and a feeding point is set near the center position of the long gap 3 to achieve a frequency range of 2400-2500MHz in the WLAN frequency band; and a small circular ring-shaped gap 5 is opened on the planar metal sheet 2 with the center of the long gap 3 as the center point, and the radius of the small circular ring-shaped gap 5 is smaller than the large circular ring-shaped gap 4, that is, the small circular ring-shaped gap 5 is located inside the circle formed by the large circular ring-shaped gap 4 to achieve resonance in the 5150-5850MHz frequency band.

[0019] Furthermore, the dielectric substrate 1 is a FR4 dielectric substrate 1 .

[0020] Furthermore, the large annular gap 4 and the small annular gap 5 are connected via a connecting gap (6, 7).

[0021] Furthermore, there are two connecting gaps (6, 7), the two connecting gaps (6, 7) are located in the half area or the lower half area of ​​the plane metal sheet 2 separated by the long gap 3, and the two connecting gaps (6, 7) are axially symmetrically arranged with a vertical line passing through the center of the long gap 3 as the symmetry axis.

[0022] Furthermore, two symmetrical and independent integral structure gaps (8, 9) are respectively provided inside the circle formed by the small circular annular gap 5 with the horizontal central axis of the long gap 3 as the symmetry axis. That is, the long gap 3 divides the small circular annular gap 5 into two semicircles, and an independent integral structure gap (8, 9) is provided in the two semicircles; the two independent integral structure gaps (8, 9) are axially symmetrically provided with the long gap 3 as the symmetry axis.

[0023] Furthermore, the integrated structural gap (8, 9) comprises two horizontal gaps and three vertical gaps, the two horizontal gaps are arranged at intervals and are parallel to the horizontal central axis of the elongated gap 3; the three vertical gaps are arranged at intervals between the two horizontal gaps, and the two ends of the three vertical gaps are respectively connected to the horizontal gaps at the corresponding ends.

[0024] Furthermore, the length of a horizontal slit far from the elongated slit 3 is greater than the length of another horizontal slit close to the elongated slit 3 .

[0025] The present invention is used to widen the bandwidth of 5150-5850 MHz in the WLAN frequency band by opening these gaps, thereby achieving the design requirements within the frequency range of 5150-5850 MHz.

[0026] The specific structure of the present invention is described clearly and completely below.

[0027] like Figure 1 As shown, the present invention discloses a dual-band dual-circular planar slot antenna for WLAN, comprising an FR4 dielectric substrate 1, a planar metal sheet 2, a slot on the planar metal sheet 2, a long slot 3, a large circular slot 4, and a small circular slot 5, the two large and small circular slots 4 and 5 are symmetrical with respect to the center point of the long slot 3, the large circular slot 4 and the small circular slot 5 are connected by slots 6 and 7 between the two large and small circular slots 4 and 5, inside the circle formed by the small circular slot 5, two symmetrical integrated structure slots 8 and 9 are opened with the horizontal center of the long slot 3, the feeding point 10 is located on the long slot 3, and the antenna realizes the WLAN dual-band antenna design by opening slots in a variety of ways.

[0028] Specifically, the present invention prints a planar metal sheet 2 on the surface of a FR4 dielectric substrate 1, opens a long slot 3 on the planar metal sheet 2, and opens a large circular slot 4 on the planar metal sheet 2 with the center of the long slot 3 as the center point, and sets a feeder 10 at a position on the long slot 3 to achieve a resonance point in the 2400-2500MHz frequency band and achieve a VSWR < 2.0 in the 2400-2500MHz frequency band. Specifically, the present invention further uses the center of the long gap 3 as the center point, and opens a small circular gap 5 on the plane metal sheet 2 inside the circle formed by the large circular gap 4 to achieve resonance in the 5150-5850MHz frequency band, and connects the large circular gap 4 and the small circular gap 5 by opening two gaps 6 and 7 between the two large and small circular gaps 4 and 5, and inside the circle formed by the small circular gap 5, two symmetrical integral structure gaps 8 and gaps 9 are opened with the horizontal center of the long gap 3 as the center point. Figure 3 As shown in FIG. 4 , the present invention uses these slots to widen the bandwidth of the entire 5150-5880 MHz frequency band and achieve VSWR < 2.0 in the 5150-5850 MHz frequency band. The antenna of the present invention has a size of 95*95*0.8mm, adopts an FR4 dielectric substrate 1, and adopts a double-circular gap and slot coupling method to achieve a design frequency of 2400-2500MHz & 5150-5850MHz, and an antenna VSWR < 2.0. The present invention realizes the technical requirements of dual-band and wide-bandwidth slot antennas, so that it is applied to WLAN local area networks, and the antenna can cover a frequency bandwidth of 2400-2500MHz & 5150-5850MHz.

[0029] The present invention adopts the above technical solution and has the following advantages: the WLAN dual-band design requirements are realized through different forms of slots, the frequency covers 2400-2500MHz & 5150-5850MHz, the antenna has good port impedance, and the antenna wide impedance bandwidth can be achieved. The antenna has good performance, is easy to process, and is easy to install conformally.

[0030] Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. In the absence of conflict, the embodiments in the present application and the features in the embodiments can be combined with each other. The components of the embodiments of the present application generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the detailed description of the embodiments of the present application is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians of the art without making creative work are within the scope of protection of the present application.

Claims

1. A dual-band dual-circular planar slot antenna for WLAN, characterized in that: It includes a dielectric substrate and a plane metal sheet; the plane metal sheet is printed on the surface of the dielectric substrate, a long gap is horizontally opened in the middle of the plane metal sheet, and small circular gaps and large circular gaps are spaced from the inside to the outside on the plane metal sheet with the center of the long gap as the center point, and a feeding point is set near the center of the long gap.

2. The dual-band dual-ring planar slot antenna for WLAN according to claim 1, characterized in that: The dielectric substrate is a FR4 dielectric substrate, and the dimensions of the dielectric substrate are 95*95*0.8 mm in length, width and height.

3. The dual-band dual-ring planar slot antenna for WLAN according to claim 1, characterized in that: The large annular gap and the small annular gap are connected via a connecting gap.

4. The dual-band dual-ring planar slot antenna for WLAN according to claim 3, characterized in that: There are two connecting gaps, which are located in the half area or the lower half area separated by the long gap on the plane metal sheet, and the two connecting gaps are axially symmetrically arranged with the vertical line passing through the center of the long gap as the symmetry axis.

5. The dual-band dual-ring planar slot antenna for WLAN according to claim 1, characterized in that: Two symmetrical and independent integral structural gaps are respectively provided inside the circle formed by the small circular annular gap with the horizontal central axis of the long gap as the symmetry axis.

6. The dual-band dual-ring planar slot antenna for WLAN according to claim 5, characterized in that: The integrated structural gap includes two horizontal gaps and three vertical gaps. The two horizontal gaps are arranged at intervals and are parallel to the horizontal central axis of the long gap. The three vertical gaps are arranged at intervals between the two horizontal gaps. The two ends of the three vertical gaps are respectively connected to the horizontal gaps at the corresponding ends.

7. The dual-band dual-ring planar slot antenna for WLAN according to claim 6, characterized in that: The length of a horizontal slit far from the elongated slit is greater than the length of another horizontal slit close to the elongated slit.

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