Miniature mining multi-polarization broadband 5G CPE built-in antenna

Abstract

The invention relates to the technical field of wireless communication, in particular to a small mining multi-polarization broadband 5G CPE built-in antenna which comprises a substrate and an antenna layer, and the antenna layer is arranged on the substrate and comprises a first metal area, two second metal areas and two third metal areas. A first part of the first metal area and a second metal area form a first sub-antenna, a second part of the first metal area and a third metal area form a second sub-antenna, and a third part of the first metal area and another second metal area form a third sub-antenna. The fourth part of the first metal area and the other third metal area form a fourth sub-antenna, the first sub-antenna and the third sub-antenna are in rotational symmetry about the center point of the antenna layer, and the second sub-antenna and the fourth sub-antenna are in rotational symmetry about the center point of the antenna layer. The small mining multi-polarization broadband 5G CPE built-in antenna is good in omnidirectional radiation, wide in frequency band coverage, high in universality, simple and compact in structure and low in implementation cost.

Description

Technical Field

[0001] The present invention relates to the field of wireless communication technology, and in particular to a small-scale mining multi-polarization broadband 5G CPE built-in antenna. Background Art

[0002] In recent years, with the widespread application of 5G mobile communication technology, its technical advantages such as large bandwidth, low latency, and wide access have greatly promoted the intelligentization process of coal mines. The mine 5G wireless communication system includes a core network platform, ground 5G base stations, underground base stations, underground HUBs, 5G customer premises equipment (CPE), and various underground wireless mobile terminals. Among them, 5G CPE, as an IoT wireless communication base station, can provide users with wireless data transmission functions by utilizing 3G / 4G / 5G networks. It plays a key role in terminal access to the network and helps promote the high-quality development of remote control in coal mines.

[0003] Currently, 5G CPE antennas are mainly divided into two types: external and internal. Although external antennas have the characteristics of high gain and good omnidirectionality, coal mines are confined spaces, and have high requirements for installation space and location. External antennas are not widely used in coal mine working environments. Compared with external antennas, internal antennas have higher integration and are more suitable for coal mine working environments.

[0004] Currently, most 5G CPE built-in antennas are PCB structures. According to the number of RF channels in the CPE module, multiple PCB antennas are arranged at a certain distance, such as Figure 1 As shown in the figure, the shortcomings of the existing 5G CPE structure are:

[0005] 1) The antennas are arranged in parallel, mostly in a single-polarized radiation mode. However, unlike the relatively open environment on the ground, the underground coal mine is a confined space with a narrow and long tunnel structure and a small cross-section. Cables, water pipes, rails, wire ropes, overhead lines, and tape racks are laid axially in the tunnel. Internal I-beam support and hydraulic supports for the fully mechanized working face are erected horizontally. Electromagnetic waves are severely blocked in the tunnel. The existing single-polarized internal antenna arrangement has poor anti-interference ability in underground coal mines.

[0006] 2) In order to reduce the mutual coupling between antennas, antennas need to be spaced a certain distance apart, which places high demands on the overall space;

[0007] 3) Each antenna is independent, and the number of antennas corresponds to the RF channel. For CPE modules that support 5G MIMO, the number of antennas is positively correlated with the number of RF channels, and the design redundancy of space and mutual coupling is further reduced. Summary of the invention

[0008] The present invention aims to solve at least one of the technical problems existing in the prior art.

[0009] To this end, the present invention provides a small-scale mining multi-polarization broadband 5G CPE built-in antenna with good omnidirectional radiation, wide frequency band coverage, high versatility, simple and compact structure and low implementation cost.

[0010] A small-scale multi-polarization broadband 5G CPE internal antenna for mining according to an embodiment of the present invention includes:

[0011] substrate,

[0012] An antenna layer, wherein the antenna layer is arranged on the substrate, and the antenna layer includes a first metal area, two second metal areas and two third metal areas, wherein a first part of the first metal area and a second metal area constitute a first sub-antenna, a second part of the first metal area and a third metal area constitute a second sub-antenna, a third part of the first metal area and another second metal area constitute a third sub-antenna, a fourth part of the first metal area and another third metal area constitute a fourth sub-antenna, the first sub-antenna and the third sub-antenna are rotationally symmetric about a center point of the antenna layer, and the second sub-antenna and the fourth sub-antenna are rotationally symmetric about a center point of the antenna layer.

[0013] The beneficial effect of the present invention is that the present invention integrates four sub-antennas through structural design, and has the advantages of wide frequency domain coverage, wide-area spatial omnidirectional radiation, high polarization isolation, high antenna unit integration, small and compact overall structure and low cost. It can effectively release the space demand of 5G CPE built-in antenna, has good application prospects, and can be compatible with existing wireless communication systems underground in coal mines.

[0014] According to an embodiment of the present invention, each of the first sub-antenna, the second sub-antenna, the third sub-antenna and the fourth sub-antenna corresponds to a feeding port and is fed by a feed source with a characteristic impedance of 50Ω.

[0015] According to an embodiment of the present invention, the polarization modes of the first sub-antenna and the third sub-antenna are vertical polarization, and the polarization modes of the second sub-antenna and the fourth sub-antenna are horizontal polarization.

[0016] According to one embodiment of the present invention, two L-shaped slots and two T-shaped slots are formed on the first metal region, the two L-shaped slots are located on the upper and lower sides of the first metal region, and the two T-shaped slots are located on the left and right sides of the first metal region.

[0017] According to one embodiment of the present invention, the size of the substrate is 114 mm×70 mm×1.5 mm, and the substrate is a FR-4 dielectric substrate with a relative dielectric constant of 4.3 and a loss tangent of 0.02.

[0018] According to one embodiment of the present invention, the width W3 of the vertical portion of the L-shaped slot is 1 mm, and the length L 17 =29mm, the width W7 of the horizontal part of the L-shaped slot is =2mm, the length L 16 =26.5mm.

[0019] According to one embodiment of the present invention, the width W5 of the vertical portion of the T-shaped slot is 1 mm, and the length L 12 =18mm, the width W6 of the horizontal part of the T-shaped slot is 2.1mm, the length L 11 =29mm.

[0020] According to one embodiment of the present invention, the second metal region includes a first rectangular branch with a length L3 = 32 mm and a width W2 = 10 mm, and the distance between the width of the first rectangular branch and the first metal region is g1 = g2 = 1 mm.

[0021] According to one embodiment of the present invention, one side of the first rectangular branch has an L-shaped branch, and the L-shaped branch includes a length L 13 =10mm, width W4 =3mm and length L 14 =4mm, and a connecting portion with a width W4=3mm, wherein the rectangular portion is located on a side of the connecting portion away from the T-shaped slot groove, and a distance L between the connecting portion and the width of the first rectangular branch close to the T-shaped slot groove 15 =4mm.

[0022] According to one embodiment of the present invention, the third metal region is a second rectangular branch with a length of L7=19mm and a width of W8=8mm. The distance between the length of the second rectangular branch and the first metal region is L6=15.8mm, and the distance between the width of the second rectangular branch and the first metal region is L9-L7=1mm.

[0023] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention are realized and obtained by the structures particularly pointed out in the description, claims and drawings.

[0024] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0026] Figure 1This is a schematic diagram of the existing 5G CPE structure.

[0027] Figure 2 It is a schematic diagram of the structure of the built-in antenna of the small-scale mining multi-polarization broadband 5G CPE of the present invention.

[0028] Figure 3 This is a schematic diagram of the dimensions of the built-in antenna of the small-scale multi-polarization broadband 5G CPE for mining of the present invention.

[0029] Figure 4 It is a schematic diagram of the antenna layer structure of the present invention.

[0030] Figure 5 It is a schematic diagram of the current distribution on the surface of the first sub-antenna at various operating frequencies of the present invention.

[0031] Figure 6 It is a schematic diagram of the current distribution on the surface of the second sub-antenna at various operating frequencies of the present invention.

[0032] Figure 7 This is the S parameter result of the small-scale mining multi-polarization broadband 5G CPE built-in antenna of the present invention.

[0033] Figure 8 It is the 3-D far-field radiation pattern of each frequency point of the first sub-antenna of the present invention.

[0034] Fig. 9 It is the 3-D far-field radiation pattern of each frequency point of the second sub-antenna of the present invention.

[0035] Fig.10 It is a gain-frequency result diagram of the first sub-antenna and the second sub-antenna of the present invention.

[0036] In the figure: 1, substrate; 2, antenna layer; 21, first metal area; 22, second metal area; 23, third metal area; 211, L-shaped slot; 212, T-shaped slot; 221, first rectangular branch; 222, L-shaped branch; 231, second rectangular branch. DETAILED DESCRIPTION

[0037] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, which only illustrate the basic structure of the present invention in a schematic manner, and therefore only show the components related to the present invention.

[0038] 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 positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0039] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" 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 a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0040] An embodiment of the present application provides a small-scale multi-polarization broadband 5G CPE built-in antenna for mining, as shown in 2-4, including: a substrate 1 and an antenna layer 2, the antenna layer 2 is arranged on the substrate 1, the antenna layer 2 includes a first metal area 21, two second metal areas 22 and two third metal areas 23, the first part of the first metal area 21 and a second metal area 22 constitute a first sub-antenna, the second part of the first metal area 21 and a third metal area 23 constitute a second sub-antenna, the third part of the first metal area 21 and another second metal area 22 constitute a third sub-antenna, the fourth part of the first metal area 21 and another third metal area 23 constitute a fourth sub-antenna, the first sub-antenna and the third sub-antenna are rotationally symmetrical about the center point of the antenna layer 2, and the second sub-antenna and the fourth sub-antenna are rotationally symmetrical about the center point of the antenna layer 2.

[0041] In the embodiment, the first sub-antenna, the second sub-antenna, the third sub-antenna and the fourth sub-antenna each correspond to a feeding port (the feeding ports of the first sub-antenna, the second sub-antenna, the third sub-antenna and the fourth sub-antenna correspond to Figure 4 The first and third sub-antennas have vertical polarization modes, and the second and fourth sub-antennas have horizontal polarization modes.

[0042] The first metal region 21 has two L-shaped slots 211 and two T-shaped slots 212 . The two L-shaped slots 211 are located at the upper and lower sides of the first metal region 21 , and the two T-shaped slots 212 are located at the left and right sides of the first metal region 21 .

[0043] The size of the substrate 1 is 114 mm×70 mm×1.5 mm. The substrate 1 is a FR-4 dielectric substrate with a relative dielectric constant of 4.3 and a loss tangent of 0.02.

[0044] The vertical portion of the L-shaped slot 211 has a width W3 of 1 mm and a length L 17 = 29mm, the width W7 of the horizontal part of the L-shaped slot 211 = 2mm, the length L 16 =26.5mm.

[0045] The vertical portion of the T-shaped slot 212 has a width W5 = 1 mm and a length L 12 =18mm, the width W6 of the horizontal part of the T-shaped slot 212 =2.1mm, the length L 11 =29mm.

[0046] The second metal region 22 includes a first rectangular branch 221 with a length L3 =32 mm and a width W2 =10 mm. The distance between the width of the first rectangular branch 221 and the first metal region 21 is g1 =g2 =1 mm.

[0047] One side of the first rectangular branch 221 has an L-shaped branch 222, and the L-shaped branch 222 includes a length L 13 =10mm, width W4 =3mm and length L 14 =4mm, the width W4=3mm of the connecting portion, the rectangular portion is located on the side of the connecting portion away from the T-shaped slot groove 212, and the distance L between the connecting portion and the width of the first rectangular branch 221 close to the T-shaped slot groove 212 15 =4mm.

[0048] The third metal region 23 is a second rectangular branch 231 with a length of L7=19 mm and a width of W8=8 mm. The distance between the length of the second rectangular branch 231 and the first metal region 21 is L6=15.8 mm, and the distance between the width of the second rectangular branch 231 and the first metal region 21 is L9-L7=1 mm.

[0049] Taking the first antenna and the second antenna as an example, above the first rectangular branch 221 near the first sub-antenna, the side width W1 of the upper part of the first part of the first metal region 21 is 9.1mm, below the first rectangular branch 221 near the first sub-antenna, the side width L4 of the lower part of the first part of the first metal region 21 is 11.95mm, the distance from the right T-shaped slot 212 to the third metal region 23 of the second sub-antenna is L5+L6, L5=30.95mm, and the distance from the lower L-shaped slot 211 to the third metal region 23 of the second sub-antenna is L8+1mm, L8=13.5mm. Since the first sub-antenna and the third sub-antenna are rotationally symmetric about the center point of the antenna layer 2, and the second sub-antenna and the fourth sub-antenna are rotationally opposite about the center point of the antenna layer 2, for the sake of simplicity, the third sub-antenna and the fourth sub-antenna are not repeated here. Since the first sub-antenna and the third sub-antenna are rotationally symmetric about the center point of the antenna layer 2, the second sub-antenna and the fourth sub-antenna are rotationally symmetric about the center point of the antenna layer 2, and the feeding port characteristics of each sub-antenna are exactly the same, the working principle is explained by taking the first sub-antenna and the second sub-antenna as examples.

[0050] When energy is fed into the feeding port of the first sub-antenna, the metal area on the first sub-antenna is excited and exhibits multi-mode radiation characteristics. Figure 5 Schematic diagram of the current distribution on the surface of the first sub-antenna at each operating frequency is shown. Figure 5 It can be seen that the fundamental mode induced current generated by the first part of the first metal region 21 is radiated at a frequency of 703 MHz; at a frequency of 2.3 GHz, the radiation of the antenna mainly depends on the fundamental mode induced current of the first rectangular branch 221; at a frequency of 2.7 GHz, the first part of the first metal region 21 and the induced current of the first rectangular branch 221 and the L-shaped branch 222 together constitute the radiation arm of the antenna; at a frequency of 3.5 GHz, the radiation of the first sub-antenna mainly depends on the high-order mode induced current of the first part of the first metal region 21 and the induced current generated by the L-shaped branch 222; at a frequency of 4 GHz, the radiation of the first sub-antenna mainly depends on the second rectangular branch 231. In addition, since the fundamental mode radiation bandwidth of the first part of the first metal area 21 is narrow and cannot completely cover the 5G N28 frequency band (703-803 MHz), in order to compensate for the low-frequency passband bandwidth of the first sub-antenna, the set T-shaped slot 212 can provide another slot coupling induced current path. By changing the length of the T-shaped slot 212, the resonant frequency of the induced current can be tuned, thereby effectively expanding the low-frequency bandwidth.

[0051] Compared with the first sub-antenna, the radiation pattern of the second sub-antenna is relatively simple. When energy is fed from the feeding port of the second sub-antenna, the radiation from the second sub-antenna mainly relies on the second rectangular branch 231 (third metal region 23) and the second part of the first metal region 21 to form a monopole radiation pattern. Figure 6 As shown, at lower frequencies (1.7-2.7 GHz), since the corresponding wavelength is larger, the radiation of the antenna mainly relies on the second part of the first metal region 21; in the high frequency band (>3 GHz), as the wavelength becomes smaller, the radiation of the antenna mainly relies on the second rectangular branch 231 (third metal region 23).

[0052] Since the overall size of the built-in antenna is compact and it integrates four sub-antenna units, in order to improve the isolation between the ports of the antenna and reduce the mutual coupling, the method of introducing floor slots is mainly adopted in this embodiment. Specifically, the introduction of the T-shaped slot 212 not only plays the role of expanding the low-frequency bandwidth as mentioned above, but also plays the role of isolating the mutual coupling of the floor current between the first sub-antenna and the second sub-antenna, and the third sub-antenna and the fourth sub-antenna, thereby improving the isolation between the two pairs of antennas. By introducing the L-shaped slot 211, the mutual coupling of the floor current between the first sub-antenna and the third sub-antenna can be isolated, thereby improving the isolation between the two pairs of antennas.

[0053] Depend on Figure 7 It can be seen that the -6dB bandwidth of the feeding port of the first sub-antenna and the feeding port of the third sub-antenna is 670MHz~900MHz&&1.9GHz~6GHz, and the corresponding polarization mode is vertical polarization (along the y-axis direction); the -6dB bandwidth of the feeding port of the second sub-antenna and the feeding port of the fourth sub-antenna is 1.7GHz~6GHz, and the corresponding polarization mode is horizontal polarization (along the x-axis direction). In the frequency bands of 703~803MHz and 1.9~5.0GHz, the transmission coefficients (S2,1, 3,1, 4,1; S3,2, S4,2; S4,3) between the feeding ports of the first sub-antenna to the fourth sub-antenna are all lower than -10dB.

[0054] Due to the symmetry between the first and third sub-antennas, and between the second and fourth sub-antennas, Figure 8 and Fig. 9 The 3-D far-field radiation patterns of the first sub-antenna and the second sub-antenna at each frequency point are shown. As can be seen from the figure, within their respective impedance bandwidths, the first sub-antenna and the second sub-antenna both maintain good omnidirectional radiation characteristics, which can well meet the needs of wide-area coverage.

[0055] Fig.10A curve chart showing the gain variation of the first sub-antenna and the second sub-antenna with frequency is shown. It can be seen from the figure that the gain of the first sub-antenna is -1dBi to 3.2dBi and 2dBi to 5.3dBi respectively in the frequency bands of 70MHz to 900MHz and 1.9GHz to 4.2GHz; the gain of the second sub-antenna is 1.8dBi to 4.3dBi in the frequency band of 1.7GHz to 4.2GHz.

[0056] The present invention is a small-scale multi-polarization broadband 5G CPE built-in antenna for mining, which integrates four sub-antennas through structural design. It has the advantages of wide frequency domain coverage, wide-area omnidirectional radiation, high polarization isolation, high antenna unit integration, small and compact overall structure and low cost. It can effectively release the space demand of 5G CPE built-in antenna, has good application prospects, and can be compatible with existing wireless communication systems underground in coal mines.

[0057] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0058] Based on the above ideal embodiments of the present invention, the relevant staff can make various changes and modifications without departing from the technical concept of the present invention through the above description. The technical scope of the present invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A small-scale multi-polarized broadband 5G CPE internal antenna for mining, characterized in that: include: base(1), An antenna layer (2), the antenna layer (2) being arranged on the substrate (1), the antenna layer (2) comprising a first metal region (21), two second metal regions (22) and two third metal regions (23), the first part of the first metal region (21) and a second metal region (22) forming a first sub-antenna, the second part of the first metal region (21) and a third metal region (23) forming a second sub-antenna, the third part of the first metal region (21) and another second metal region (22) forming a third sub-antenna, the fourth part of the first metal region (21) and another third metal region (23) forming a fourth sub-antenna, the first sub-antenna and the third sub-antenna being rotationally symmetrical about a center point of the antenna layer (2), and the second sub-antenna and the fourth sub-antenna being rotationally symmetrical about a center point of the antenna layer (2).

2. The small-scale mining multi-polarization broadband 5G CPE internal antenna as claimed in claim 1, characterized in that: The first sub-antenna, the second sub-antenna, the third sub-antenna and the fourth sub-antenna each have a corresponding feeding port and are fed by a feed source with a characteristic impedance of 50Ω.

3. The small-scale mining multi-polarization broadband 5G CPE internal antenna as claimed in claim 1, characterized in that: The polarization modes of the first sub-antenna and the third sub-antenna are vertical polarization, and the polarization modes of the second sub-antenna and the fourth sub-antenna are horizontal polarization.

4. The small-scale mining multi-polarization broadband 5G CPE internal antenna as claimed in claim 3 is characterized in that: The first metal region (21) is provided with two L-shaped slot grooves (211) and two T-shaped slot grooves (212); the two L-shaped slot grooves (211) are located on the upper and lower sides of the first metal region (21), and the two T-shaped slot grooves (212) are located on the left and right sides of the first metal region (21).

5. The small-scale multi-polarized broadband 5G CPE internal antenna for mining as claimed in claim 4 is characterized in that: The size of the substrate (1) is 114 mm×70 mm×1.5 mm. The substrate (1) is a FR-4 dielectric substrate with a relative dielectric constant of 4.3 and a loss tangent of 0.

02.

6. The small-scale mining multi-polarization broadband 5G CPE internal antenna as claimed in claim 4, characterized in that: The vertical portion of the L-shaped slot (211) has a width W3=1 mm and a length L 17 =29mm, the width W7 of the horizontal part of the L-shaped slot (211) =2mm, the length L 16 =26.5mm.

7. The small-scale mining multi-polarization broadband 5G CPE internal antenna as claimed in claim 4, characterized in that: The vertical portion of the T-shaped slot (212) has a width W5=1 mm and a length L 12 =18mm, the width W6 of the horizontal part of the T-shaped slot (212) =2.1mm, the length L 11 =29mm.

8. The small-scale multi-polarized broadband 5G CPE internal antenna for mining as claimed in claim 4, characterized in that: The second metal region (22) comprises a first rectangular branch (221) with a length L3=32 mm and a width W2=10 mm, and the distance between the width of the first rectangular branch (221) and the first metal region (21) is g1=g2=1 mm.

9. The small-scale multi-polarized broadband 5G CPE internal antenna for mining as claimed in claim 8, characterized in that: One side of the first rectangular branch (221) has an L-shaped branch (222), and the L-shaped branch (222) includes a length L 13 =10mm, width W4 =3mm and length L 14 =4mm, and a connecting portion with a width W4=3mm, wherein the rectangular portion is located on a side of the connecting portion away from the T-shaped slot groove (212), and a distance L between the connecting portion and the width of the first rectangular branch (221) close to the T-shaped slot groove (212) is 15 =4mm.

10. The small-scale multi-polarized broadband 5G CPE internal antenna for mining as claimed in claim 4, characterized in that: The third metal region (23) is a second rectangular branch (231) with a length of L7=19 mm and a width of W8=8 mm. The distance between the length of the second rectangular branch (231) and the first metal region (21) is L6=15.8 mm, and the distance between the width of the second rectangular branch (231) and the first metal region (21) is L9-L7=1 mm.

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