Directional dual-band dual-polarization MIMO antenna and smart device

Abstract

The present invention discloses a directional dual-frequency dual-polarization MIMO antenna and intelligent device. The directional dual-frequency dual-polarization MIMO antenna comprises a substrate and a ground plate. The substrate is provided with a square metal patch. The ground plate and the substrate are arranged side by side and connected to each other through a supporting column. The square metal patch is provided with a plurality of irregular U-shaped grooves. The openings of the plurality of irregular U-shaped grooves face the middle of the square metal patch. The irregular U-shaped grooves are clearance areas. The irregular U-shaped grooves comprise a first section, a second section and a third section connected in sequence in a U shape. The length of the first section is greater than the length of the third section. The present invention is used to solve the technical problem that the microstrip patch antenna has a single working frequency band.

Description

Technical Field

[0001] The present invention relates to the field of antenna technology, and in particular to a directional dual-frequency dual-polarization MIMO antenna and an intelligent device. Background Art

[0002] In recent years, with the development of wireless communications, wireless local area networks (WLAN) have been widely used, and antennas working in the WLAN frequency band have also attracted extensive research. And as communication systems become increasingly complex, there are more and more types of antennas in response to changes in application scenarios. Microstrip patch antennas are a special type of antenna. When the radiating unit of a microstrip patch antenna is square, the antenna only works in one frequency band and has a narrow bandwidth. Summary of the invention

[0003] The main purpose of the present invention is to provide a directional dual-frequency dual-polarization MIMO antenna, aiming to solve the technical problem that the existing microstrip patch antenna has a single operating frequency band when the radiation unit is square.

[0004] To achieve the above object, the present invention proposes a directional dual-frequency dual-polarization MIMO antenna, wherein the directional dual-frequency dual-polarization MIMO antenna comprises:

[0005] A substrate provided with a square metal patch;

[0006] A ground plate, arranged side by side with the base plate and connected to each other through a support column;

[0007] The square metal patch is provided with a plurality of irregular U-shaped grooves, the openings of the plurality of irregular U-shaped grooves are toward the middle of the square metal patch, the irregular U-shaped grooves are a clearance area, the irregular U-shaped grooves include a first section, a second section and a third section connected in sequence in a U shape, and the length of the first section is greater than the length of the third section.

[0008] Optionally, the number of the irregular U-shaped grooves is four, and they are arranged on four plate edges of the square metal patch. The four irregular U-shaped grooves are opposite to each other and are symmetrical about the center of the square metal patch.

[0009] Optionally, the four sides of the square metal patch are all 48 mm in length.

[0010] Optionally, the substrate is provided with a first feeding point and a second feeding point, and the first feeding point and the second feeding point are respectively connected to the square metal patch.

[0011] Optionally, the first feeding point and the second feeding point are provided with rectangular gaps, and the rectangular gaps are clearance areas.

[0012] Optionally, the first feeding point and the second feeding point are both 16 to 18 mm away from a center position of the square metal patch.

[0013] Optionally, the irregular U-shaped groove is 4 mm away from the center of the square metal patch, the long side length of the irregular U-shaped groove is 13 mm, the short side length of the irregular U-shaped groove is 5 mm, and the width of the irregular U-shaped groove is 0.4 mm.

[0014] Optionally, the distance between the square metal patch and the ground plate is 4.5-6.5 mm.

[0015] Optionally, the distance between the square metal patch and the ground plate is 6 mm.

[0016] To achieve the above objective, the present invention further proposes a smart device, comprising the directional dual-frequency dual-polarization MIMO antenna as described above.

[0017] The present invention proposes a directional dual-frequency dual-polarization MIMO antenna, which is composed of a substrate and a ground plate, wherein a square metal patch is arranged on the substrate, and the ground plate and the substrate are arranged side by side and connected to each other through a support column. At this time, the square metal patch uses the entire ground plate as a reflector, thereby realizing the characteristic of directional operation of the antenna and increasing the gain of the antenna at the same time. In addition, a plurality of irregular U-shaped grooves are arranged on the square metal patch to excite a new working frequency band. At this time, the new working frequency band excited by the irregular U-shaped groove serves as a parasitic working frequency band of the square metal patch, so that the square metal patch provided with a plurality of irregular U-shaped grooves can simultaneously work in the original frequency band and the working frequency band excited by the irregular U-shaped groove. The openings of the plurality of irregular U-shaped grooves face the middle of the square metal patch, and the irregular U-shaped grooves are in a clearance area. The irregular U-shaped grooves include a first section, a second section, and a third section connected in a U shape in sequence, and the length of the first section is greater than the length of the third section, wherein the length of the first section is greater than the length of the third section.

[0018] The directional dual-frequency dual-polarization MIMO antenna can be made to work in multiple frequency bands, and the long end and the short end are fixedly connected through the connection end to enhance resonance. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0020] Figure 1 It is a structural schematic diagram of a directional dual-frequency dual-polarization MIMO antenna of the present invention;

[0021] Figure 2 A simulation schematic diagram of an embodiment of a directional dual-frequency dual-polarization MIMO antenna of the present invention;

[0022] Figure 3 A simulation schematic diagram of an embodiment of a directional dual-frequency dual-polarization MIMO antenna of the present invention;

[0023] Figure 4 A simulation diagram of an embodiment of a directional dual-frequency dual-polarization MIMO antenna according to the present invention

[0024] Figure 5 It is a schematic diagram of the radiation direction of the directional dual-frequency dual-polarization MIMO antenna of the present invention.

[0025] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0028] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0029] The present invention provides a directional dual-frequency dual-polarization MIMO antenna, which is used to solve the technical problem that the existing patch antenna can only work in one frequency band.

[0030] In one embodiment, if Figure 1 As shown, a directional dual-band dual-polarization MIMO antenna is proposed, which is composed of a substrate 10 and a ground plate 20, wherein a square metal patch 30 is arranged on the substrate 10, and the ground plate 20 and the substrate 10 are arranged side by side and connected to each other through a supporting column. At this time, the square metal patch 30 uses the entire ground plate 20 as a reflector, thereby realizing the directional working characteristics of the antenna and increasing the gain of the antenna at the same time. In addition, a plurality of irregular U-shaped grooves (401, 402, 403, 404) are provided on the square metal patch 30 to change the current on the square metal patch 30, thereby exciting a new working frequency band. At this time, the new working frequency band excited by the irregular U-shaped grooves (401, 402, 403, 404) serves as a parasitic working frequency band of the square metal patch 30, so that the square metal patch 30 provided with a plurality of irregular U-shaped grooves (401, 402, 403, 404) can simultaneously work in the original frequency band and the working frequency band excited by the irregular U-shaped grooves (401, 402, 403, 404). The openings of the plurality of irregular U-shaped grooves (401, 402, 403, 404) are oriented toward the middle of the square metal patch 30, and the irregular U-shaped grooves (401, 402, 403, 404) are clearance areas, that is, the irregular U-shaped grooves are hollowed out, and the irregular U-shaped grooves (401, 402, 403, 404) include a first section, a second section, and a third section connected in sequence in a U shape, and the length of the first section is greater than the length of the third section, wherein the length of the first section is greater than the length of the third section, so that the directional dual-frequency dual-polarization MIMO antenna can operate in multiple frequency bands, and the long end and the short end are fixedly connected by a connecting end to enhance resonance.

[0031] In one embodiment, the number of the irregular U-shaped grooves (401, 402, 403, 404) is four, which are arranged at four plate edges of the square metal patch 30. The four irregular U-shaped grooves (401, 402, 403, 404) are opposite to each other and are symmetrical about the center of the square metal patch 30. And the irregular U-shaped grooves (401, 402, 403, 404) are symmetrically arranged along the center of the square metal patch 30. The irregular U-shaped grooves (401, 402, 403, 404) are symmetrically arranged, so that the MIMO antenna has horizontal polarization and vertical polarization, thereby improving the isolation of the four irregular U-shaped grooves (401, 402, 403, 404), increasing the receiving and transmitting performance of the antenna, so that the antenna can achieve better receiving and transmitting effects in multiple directions, and effectively improving the antenna gain.

[0032] In one embodiment, under the premise that the antenna is designed based on the working frequency bands of 2.5 GHz and 5.8 GHz, the lengths of the four sides of the square metal patch 30 are all 48 mm. This makes the working frequency of the antenna closer to the design frequency. The antenna can work at 2.5 GHz and 5.8 GHz at the same time.

[0033] In one embodiment, if Figure 1 As shown, the substrate 10 is provided with a first feeding point 501 and a second feeding point. The first feeding point 501 and the second feeding point 502 are respectively connected to the square metal patch 30 and are fed by coaxial lines.

[0034] In the above embodiment, in order to better reduce the interference of external and internal electromagnetic waves on the antenna working frequency band, a coaxial line with a characteristic impedance of 50Ω can be selected.

[0035] In one embodiment, the first feeding point 501 and the second feeding point 502 are respectively arranged at the U-shaped metal part surrounded by the U-shaped grooves of two adjacent irregular U-shaped grooves (401, 402, 403, 404) and are placed in the center of the U-shaped grooves to improve the dual-polarization feeding of the antenna, thereby increasing the receiving and transmitting performance of the antenna.

[0036] In one embodiment, in order to increase the isolation between the first feeding point 501 and the second feeding point 502, thereby further improving the transmission efficiency of the antenna, a rectangular gap 60 is provided at the first feeding point 501 and the second feeding point 502, and the rectangular gap 60 is a clearance area.

[0037] In one embodiment, the high frequency of the antenna is greatly affected by the feeding point. As shown in the figure, the resonant frequency increases as the distance between the feeding point and the center position increases. In order to achieve better impedance matching, under the premise that the antenna is designed based on the working frequency bands of 2.5 GHz and 5.8 GHz, the first feeding point 501 and the second feeding point 502 are both 16 to 18 mm away from the center position of the square metal patch 30.

[0038] When the distance between the first feeding point 501 and the second feeding point 502 and the center of the square metal patch 30 is 17.5 mm, the high frequency operating point of the antenna is 5.8 GHz.

[0039] In one embodiment, in order to better enhance the resonance and increase the isolation between the first feeding point 501 and the second feeding point 502, the distance between the irregular U-shaped groove (401, 402, 403, 404) and the center position of the square metal patch 30 is 4 mm, the long side length of the irregular U-shaped groove (401, 402, 403, 404) is 13 mm, the short side length of the irregular U-shaped groove (401, 402, 403, 404) is 5 mm, and the U-shaped groove width of the irregular U-shaped groove (401, 402, 403, 404) is 0.4 mm.

[0040] In one embodiment, in order to increase isolation, the support column is a plastic column.

[0041] In one embodiment, in order to make the antenna have better impedance matching performance, as shown in the figure, the low-frequency band of the antenna will not change with the change of the distance between the square metal patch 30 and the ground plate 20, while the high-frequency band will decrease its resonant frequency as the distance between the square metal patch 30 and the ground plate 20 increases. The distance between the square metal patch 30 and the ground plate 20 is 4.5 to 6.5 mm.

[0042] In one embodiment, the distance between the square metal patch 30 and the ground plate 20 is 6 mm, which can achieve better impedance matching performance in the 5.8 GHz operating frequency band.

[0043] Based on the above embodiment, the directional dual-frequency dual-polarization MIMO antenna is simulated using software, and the measured performance is as follows:

[0044] After setting the irregular U-shaped slots (401, 402, 403, 404), the directional dual-frequency dual-polarization MIMO antenna is simulated, as shown in FIG. Figure 2 As shown, the test obtained simulation data is as follows, the frequency of endpoint m1 in the figure is 2.56GHz, the reflection coefficient is -10dB, the frequency of m3 is 2.40GHz, the reflection coefficient is -10dB, the frequency of m2 is 6.00GHz, the reflection coefficient is -10dB, the frequency of m4 is 5.60GHz, the reflection coefficient is -10dB. Based on the above data and combined with Figure 2 It can be seen that the reflection coefficient of the improved MIMO antenna is around -10dB near 2.5GHz and 5.8GHz, which is better than the existing antenna.

[0045] After the irregular U-shaped grooves (401, 402, 403, 404) and the rectangular gap 60 are provided, Figure 3As shown, the test obtained simulation data is as follows, the frequency of endpoint m5 in the figure is 2.40GHz, the reflection coefficient is -11dB, the frequency of m6 is 2.54GHz, the reflection coefficient is -10dB, the frequency of m7 is 5.67GHz, the reflection coefficient is -10dB, the frequency of m8 is 6.09GHz, and the reflection coefficient is -10dB. The above data and combined Figure 3 It can be seen that the reflection coefficient of the improved MIMO antenna is around -10dB near 2.5GHz and 5.8GHz, which is better than the existing antenna.

[0046] The third test results are as follows: Figure 4 As shown, the test obtained simulation data as follows, the frequency of the endpoint m10 in the figure is 2.14GHz, the transmission coefficient is -20dB, the frequency of m9 is 2.54GHz, the transmission coefficient is -20dB, the frequency of m11 is 5.36GHz, the transmission coefficient is -20dB, the frequency of m12 is 6.00GHz, and the transmission coefficient is -20dB. At this time, the relevant parameters of the irregular U-shaped groove (401, 402, 403, 404) and the parameters of the rectangular slot 60 and the position of the feeding point are set according to the relevant parameters in the above embodiment. The simulation result is obtained. At this time, near 2.5GHz and 5.8GHz, its transmission coefficient is -20dB, which is better than the existing antenna. And some frequency bands between 2.5GHz and 5.8GHz also have good simulation effects, and its transmission coefficient can also be achieved below -20dB.

[0047] like Figure 5 As shown in the figure, it is the radiation pattern (RADIATIONPATTERN) of the directional dual-band dual-polarization MIMO antenna measured. Phi is the angle with the x-axis in the xy plane, Theta is the angle with the z-axis, GainPhi is the gain in the Phi direction, the size is the read value, and the direction is the normal direction of the circular surface. GainTheta is the gain in the Theta direction, the size is the read value, and the direction is the tangent direction of the circle in the xy plane. GainTotal is the total gain, that is, the two directions are vector synthesized. Figure 5 The middle curve 701 represents the total gain after vector synthesis of the gains in the normal direction of the circular surface and the tangent direction of the circle in the xy plane. Figure 5 The gain in the normal direction of the circular surface of the middle curve 702 is Figure 5 The middle curve 703 represents the gain in the tangent direction of the circle in the xy plane. Figure 5 It can be seen that the improved antenna has the best gain in the normal direction of the circular surface.

[0048] In order to solve the above problem, the present invention further proposes a smart device, comprising the above directional dual-frequency dual-polarization MIMO antenna.

[0049] It is worth noting that, because the smart device of the present invention includes all embodiments of the above-mentioned directional dual-band dual-polarization MIMO antenna, the smart device of the present invention has all the beneficial effects of the above-mentioned directional dual-band dual-polarization MIMO antenna, which will not be repeated here.

[0050] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. All equivalent structural changes made using the contents of the present invention's specification and drawings, or directly / indirectly applied in other related technical fields, are included in the patent protection scope of the present invention.

Claims

1. A directional dual-frequency dual-polarization MIMO antenna, characterized in that: The directional dual-frequency dual-polarization MIMO antenna comprises: A substrate provided with a square metal patch; A ground plate, arranged side by side with the base plate and connected to each other through a support column; The square metal patch is provided with a plurality of irregular U-shaped grooves, the openings of the plurality of irregular U-shaped grooves face the middle of the square metal patch, and the irregular U-shaped grooves are a clearance area; the irregular U-shaped groove comprises a first section, a second section and a third section which are connected in sequence in a U shape, and the length of the first section is greater than the length of the third section; the plurality of irregular U-shaped grooves are opposite to each other and are symmetrical about the center of the square metal patch; the substrate is provided with a first feeding point and a second feeding point, and the first feeding point and the second feeding point are respectively connected to the square metal patch; the first feeding point and the second feeding point are respectively arranged in the U-shaped metal part surrounded by the U-shaped grooves of two adjacent irregular U-shaped grooves.

2. The directional dual-frequency dual-polarization MIMO antenna according to claim 1, characterized in that: The number of the irregular U-shaped grooves is four, and they are arranged on four plate edges of the square metal patch.

3. The directional dual-frequency dual-polarization MIMO antenna according to claim 2, characterized in that: The lengths of the four sides of the square metal patch are all 48 mm.

4. The directional dual-frequency dual-polarization MIMO antenna according to claim 1, characterized in that: The first feeding point and the second feeding point are provided with rectangular gaps, and the rectangular gaps are clearance areas.

5. The directional dual-frequency dual-polarization MIMO antenna according to claim 1, characterized in that: The first feeding point and the second feeding point are both 16 to 18 mm away from the center of the square metal patch.

6. The directional dual-frequency dual-polarization MIMO antenna according to claim 1, characterized in that: The irregular U-shaped groove is 4 mm away from the center of the square metal patch, the long side length of the irregular U-shaped groove is 13 mm, the short side length of the irregular U-shaped groove is 5 mm, and the width of the irregular U-shaped groove is 0.4 mm.

7. The directional dual-frequency dual-polarization MIMO antenna according to claim 1, characterized in that: The distance between the square metal patch and the ground plate is 4.5-6.5 mm.

8. The directional dual-frequency dual-polarization MIMO antenna according to claim 1, characterized in that: The distance between the square metal patch and the ground plate is 6 mm.

9. A smart device, characterized in that: It comprises a directional dual-frequency dual-polarization MIMO antenna as described in any one of claims 1-8.

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