Antenna Structure and Wireless Communication Device

Abstract

The present invention provides an antenna structure, which includes a substrate, an antenna unit, and a metal ground portion. The substrate includes a first surface and a second surface; the antenna unit is disposed on the first surface and includes a radiation portion, a feeding portion, and a feeding line, wherein the feeding line includes a first transmission line and a second transmission line that are perpendicular to each other and connected to each other, and the first transmission line is connected to the radiation portion via the feeding portion; and the metal ground portion is disposed on the second surface, wherein the metal ground portion has an edge, and the edge is perpendicular to the projection of the radiation portion on the metal ground portion; and a resonance slot is disposed on the metal ground portion, and its position corresponds to the projection of the first transmission line on the metal ground portion and between the edges. The present invention also provides a wireless communication device.

Description

Technical Field

[0001] The present invention relates to an antenna structure and a wireless communication device. Background Art

[0002] Generally speaking, in order to meet the high requirements of the fifth-generation new radio (5G NR) standard in the sub-7 GHz frequency band, it is necessary to further design the antenna to handle a high operating bandwidth and a high isolation between antennas, so as to obtain a high data rate and a high throughput of a multi-input multi-output (MIMO) system.

[0003] In systems before the 5G NR standard, the operating frequency band of the antenna is usually relatively small. Through general antenna design, such bandwidth requirements can be met. However, such antenna designs often cannot meet the high operating bandwidth and the high isolation between antennas. Therefore, how to design an antenna that meets the high operating bandwidth and the high isolation between antennas based on the 5G NR standard is an urgent problem for those skilled in the art to solve. Summary of the Invention

[0004] The present invention provides an antenna structure, including a substrate, an antenna unit, and a metal ground portion. The substrate includes a first surface and a second surface; the antenna unit is disposed on the first surface and includes a radiation portion, a feeding portion, and a feeding line, wherein the feeding line includes a first transmission line and a second transmission line that are perpendicular to each other and connected to each other, and the first transmission line is connected to the radiation portion via the feeding portion; and the metal ground portion is disposed on the second surface, wherein the metal ground portion has an edge, and the edge is perpendicular to the projection of the radiation portion on the metal ground portion; and a resonance slot is disposed on the metal ground portion, and its position corresponds to the projection of the first transmission line on the metal ground portion and the edge.

[0005] The present invention provides a wireless communication device, comprising a substrate, at least two antenna units and at least one metal ground portion. The substrate includes a first surface and a second surface; at least two antenna units are disposed on the first surface, and adjacent ones of the at least two antenna units are perpendicular to each other, wherein the at least two antenna units include at least two radiation portions, at least two feeding portions and at least two feeding lines, and each of the at least two feeding lines includes a first transmission line and a second transmission line that are perpendicular to each other and connected to each other, wherein the first transmission lines of the at least two feeding lines are respectively connected to the at least two radiation portions via the at least two feeding portions; and at least one metal ground portion is disposed on the second surface, wherein at least one isolation slot is formed in the at least one metal ground portion, and the positions thereof respectively correspond to between the projections of adjacent ones of the at least two antenna units on the at least one metal ground portion. The at least one metal ground portion has at least two edges, wherein adjacent ones of the at least two edges are perpendicular to each other, and the at least two edges are respectively perpendicular to the projections of the at least two radiation portions on the metal ground portion, and at least two resonance slots are formed in the at least one metal ground portion, and the positions thereof correspond to between the projections of the second transmission lines of the at least two feeding lines on the metal ground portion and the corresponding ones of the at least two edges.

[0006] Based on the above, the wireless communication device provided by the present invention can greatly increase the operating bandwidth of the antenna through the resonance slots of the metal ground plate. In addition, the isolation between the antennas can be further increased through the design of the isolation slots and the positions of the perpendicular antenna units. Description of the Drawings

[0007] Figure 1 The bottom perspective view of the wireless communication device is shown according to an embodiment of the present invention.

[0008] Figure 2 The top view of the wireless communication device is shown according to an embodiment of the present invention.

[0009] Figure 3 The top view of one antenna unit in the wireless communication device is shown according to an embodiment of the present invention.

[0010] Figure 4 The bottom view of the wireless communication device is shown according to an embodiment of the present invention.

[0011] Figure 5 The bottom perspective view of the wireless communication device is shown according to another embodiment of the present invention.

[0012] Figure 6 The schematic diagram of the isolation and frequency of two antenna units is shown according to an embodiment of the present invention.

[0013] Figure 7 The schematic diagram of the operating frequency bands of two antenna units is shown according to an embodiment of the present invention.

[0014] Description of the Reference Numerals:

[0015] 100: Wireless communication device

[0016] 110: Substrate

[0017] 111: First surface

[0018] 112: Second surface

[0019] 120(1) - 120(8): Antenna unit

[0020] 121: Radiation part

[0021] 1211: First radiation part

[0022] 1212: Second radiation part

[0023] 1213: Third radiation part

[0024] 122: Feeding part

[0025] 123: Grounding part

[0026] 124: Feeding line

[0027] 1241: First transmission line

[0028] 1242: Second transmission line

[0029] 1243: Feeding point

[0030] 130, 130(1) - 130(4): Metal grounding part

[0031] 131: Isolation slot

[0032] E1 - E2: Edge

[0033] 132(1) - 132(2): Resonance slot

[0034] L1 - L3: Length

[0035] W1 - W2: Width

[0036] D1 - D2: Distance Detailed implementation manners

[0037] Figure 1 The bottom perspective view of the wireless communication device 100 is shown according to an embodiment of the present invention. Figure 2 The top view of the wireless communication device 100 is shown according to an embodiment of the present invention. Figure 3 The top view of one antenna unit in the wireless communication device is shown according to an embodiment of the present invention. Figure 4 The bottom view of the wireless communication device 100 is shown according to an embodiment of the present invention. Also refer toFigures 1 to 4 The wireless communication device 100 may include a substrate 110, a pair of antenna units 120(1) to 120(2), and a metal ground portion 130.

[0038] It should be noted that although the number of antenna units 120(1) to 120(2) in this embodiment is 2 and the number of metal ground portions 130 is 1, however, the number of antenna units 120(1) to 120(2) may also be any positive even number greater than 2, and the number of metal ground portions 130 may also be any positive integer greater than 1. In addition, the number of antenna units 120(1) to 120(2) is twice the number of metal ground portions 130.

[0039] For example, Figure 5 A bottom perspective view of the wireless communication device 100 is shown according to another embodiment of the present invention. Refer to Figure 5 This embodiment shows an example of a substrate 110, eight antenna units 120(1) to 120(8), and four metal ground portions 130(1) to 130(4).

[0040] Furthermore, referring back to Figures 1 to 4 The substrate 110 may include a corresponding first surface 111 and a second surface 112, where Figure 2 the first surface 111 is shown in Figure 4 and the second surface 112 is shown in Figure 3 The antenna units 120(1) to 120(2) may be disposed on the first surface 111, and the metal ground portion 130 may be disposed on the second surface 112. In addition,

[0041] In some embodiments, the substrate 110 may be a printed circuit board (PCB) made of an insulating material, where the material of the substrate 110 may be a commonly used material for manufacturing PCBs such as polytetrafluoroethylene (PTFE) or epoxy resin (FR4). Thus, the antenna units 120(1) to 120(2) can be directly disposed on the substrate 110 by printing.

[0042] The antenna units 120(1) to 120(2) may be perpendicular to each other, and the antenna unit 120(1) may include a radiation portion 121, a feeding portion 122, a grounding portion 123, and a feeding line 124, where the feeding line 124 may include a first transmission line 1241 and a second transmission line 1242 that are perpendicular to each other and connected to each other, and the first transmission line 121 may be connected to the radiation portion 121 via the feeding portion 122.

[0043] In addition, the feeding line 124 may further include a feeding point 1243, and the antenna unit 120(1) may receive a feeding signal from a signal source through the feeding point 1243.

[0044] It should be noted that the antenna unit 120(2) may also have the same above-mentioned structure as the antenna unit 120(1). Therefore, it will not be elaborated here.

[0045] Through the above-mentioned arrangement of the antenna units 120(1) to 120(2), the polarization direction of the antenna unit 120(1) can be the y direction, and the polarization direction of the antenna unit 120(2) can be the x direction. In this way, the isolation of the antenna units 120(1) to 120(2) can be greatly improved (for example, the isolation is reduced to about -10 dB).

[0046] In some embodiments, the antenna units 120(1) to 120(2) can all be planar inverted-F antennas (PIFA). In addition, the antenna units 120(1) to 120(2) can also be other types of antennas with the above-mentioned feeding line structure (for example, monopole antennas), and the antenna units 120(1) to 120(2) can also be different types of antennas with the above-mentioned feeding line structure (for example, the antenna unit 120(1) is a PIFA antenna, and the antenna unit 120(2) is a monopole antenna). There are no other restrictions on the types of the antenna units 120(1) to 120(2).

[0047] In some embodiments, if the antenna units 120(1) to 120(2) are all PIFA antennas, the radiation part 121 of the antenna unit 120(1) may include a first radiation part 1211, a second radiation part 1212, and a third radiation part 1213, where the third radiation part 1213 can be L-shaped.

[0048] In addition, the first end of the first radiation part 1211 is connected between the second radiation part 1212 and the third radiation part 1213, and the second end of the first radiation part 1211 is connected to the feeding part 122. In addition, the third radiation part 1213 can be connected to the grounding part 123, and the grounding part 123 can be connected to the metal grounding part 130 via a via.

[0049] In some embodiments, the metal grounding part 130 can be inverted L-shaped, and the metal grounding part 130 can be made of a metal material such as copper foil.

[0050] Furthermore, the isolation slots 131 of the metal ground portion 130 can be provided on the metal ground portion 130, and their positions can respectively correspond to the projections of the antenna elements 120(1) to 120(2) on the metal ground portion 130, where the number of the isolation slots 131 can be equal to the number of the metal ground portions 130.

[0051] In some embodiments, the isolation slots 131 are rectangular, and the distance D1 between the isolation slots 131 and the projections of the antenna elements 120(1) to 120(2) on the metal ground portion 130 can be greater than 1 mm. In addition, the width W1 of the isolation slots 131 can be 3.6 mm, and the length L1 of the isolation slots 131 can be one-fourth of the wavelength of the center frequency of the operating frequency band of the antenna elements 120(1) to 120(2).

[0052] Specifically, the wavelength of the center frequency of the operating frequency band of the antenna elements 120(1) to 120(2) can be affected by the material of the substrate 110 (i.e., different materials can correspond to different wavelengths (wavelength in free space)).

[0053] In other words, the wavelength of the center frequency of the operating frequency band of the antenna elements 120(1) to 120(2) is mainly related to the effective dielectric constant (Dkeff) of the material of the substrate 110 (i.e., the value obtained by adding 1 to the dielectric constant (Dk) and dividing by 2 approximately). For example, the dielectric constant of Teflon is 3.0 to 4.5, and the dielectric constant of FR4 is 3.5.

[0054] Furthermore, an equivalent value can be obtained by taking the square root of the above effective dielectric constant first, and the wavelength of the center frequency of the operating frequency band of the antenna elements 120(1) to 120(2) is inversely proportional to these effective values.

[0055] By the above-described setting method of the isolation slots 131, resonance can be generated between the antenna elements 120(1) to 120(2) and the isolation slots 131 to block the signals generated by the antenna elements 120(1) to 120(2), thereby greatly increasing the isolation degree of the antenna elements 120(1) to 120(2) (for example, the isolation degree is further reduced to below -20 dB).

[0056] Figure 6 According to an embodiment of the present invention, a schematic diagram of the isolation degree and frequency of two antenna elements is shown. Referring simultaneously to Figure 1 and Figure 6, through the above-described setting method of the isolation slots 131, the isolation degree of the antenna units 120(1) to 120(2) can be significantly reduced to below -20 dB. In other words, the isolation degree of the antenna units 120(1) to 120(2) can meet the isolation degree requirement of the Fifth Generation New Radio (5G NR) standard (i.e., less than -20 dB).

[0057] Furthermore, referring back simultaneously to Figures 1 to 4 , the metal grounding portion 130 has edges E1 to E2, where the edges E1 to E2 can be perpendicular to each other, and the edges E1 to E2 can be respectively perpendicular to the projections of the radiation portions of the antenna units 120(1) to 120(2) on the metal grounding portion 130.

[0058] In other words, the edge E1 can be perpendicular to the projection of a part of the radiation portion 121 close to the feeding portion 122 on the metal grounding portion 130. Similarly, the edge E2 can also have a similar setting method.

[0059] In some embodiments, the lengths of the edges E1 to E2 can be half of the wavelength of the center frequency of the operating frequency band of the antenna units 120(1) to 120(2).

[0060] Furthermore, the resonance slots 132(1) to 132(2) can be provided on the metal grounding portion 130, and their positions can be between the projections of the second transmission lines of the feeding lines in the antenna units 120(1) to 120(2) on the metal grounding portion 130 and the corresponding ones among the edges E1 to E2.

[0061] In other words, the position of the resonance slot 132(1) can be between the projection of the second transmission line 1242 of the feeding line 124 on the metal grounding portion 130 and the edge E2. Similarly, the position of the resonance slot 132(2) can also have a similar setting method.

[0062] In some embodiments, the shapes of the resonance slots 132(1) to 132(2) can be L-shaped, and the lengths of the resonance slots 132(1) to 132(2) (i.e., the total length of the length L2 and the length L3) can be one-fourth of the wavelength of the center frequency of the operating frequency band of the antenna units 120(1) to 120(2).

[0063] In some embodiments, the width W2 of the resonance slots 132(1) to 132(2) can be 1 mm, and the distance D2 between the resonance slots 132(1) to 132(2) and the projections of the antenna units 120(1) to 120(2) on the metal grounding portion 130 can be greater than 1 mm.

[0064] In other words, the distance D2 between the resonance slot 132(1) and the projection of the feeding part 122 of the antenna unit 120(1) on the metal ground part 130 can be greater than 1 mm. Similarly, the resonance slot 132(2) can also have a similar arrangement.

[0065] In some embodiments, the radiation parts of the antenna units 120(1) to 120(2) (for example, the radiation part 121 of the antenna unit 120(1)) can resonate by themselves to generate a first resonance frequency band, and the resonance slots 132(1) to 132(2) can resonate with the radiation parts of the antenna units 120(1) to 120(2) respectively to generate a second resonance frequency band adjacent to the first resonance frequency band, where the operating frequency band of the antenna units 120(1) to 120(2) can include the first resonance frequency band and the second resonance frequency band.

[0066] Through the above arrangement of the resonance slots 132(1) to 132(2), the operating frequency band of the antenna units 120(1) to 120(2) can be greatly increased.

[0067] Figure 7 Schematic diagram showing the operating frequency bands (reflection coefficient and frequency) of two antenna units according to an embodiment of the present invention. Referring simultaneously to Figure 1 and Figure 7 , generally, the frequency bands n77 / n78 of the fifth-generation new radio (5G NR) standard are from 3.3 GHz to 4.2 GHz (bandwidth is 900 MHz). Through the above arrangement of the resonance slots 132(1) to 132(2), the operating frequency band of the antenna units 120(1) to 120(2) is 3.19 to 4.46 GHz (frequency band less than -10 dB). In other words, the operating frequency band of the antenna units 120(1) to 120(2) can simultaneously meet the frequency bands n77 / n78 of the 5G NR standard.

[0068] In this way, referring back simultaneously to Figures 1 to 4 , the antenna unit 120(1), the resonance slot 132(1), a part of the substrate 130, and a part of the metal ground part 130 (this part of the substrate 130 and this part of the metal ground part 130 correspond to the antenna unit 120(1) and the resonance slot 131(1)) can form a resonance structure. Similarly, the antenna unit 120(2), the resonance slot 132(2), another part of the substrate 130, and another part of the metal ground part 130 (this other part of the substrate 130 and this other part of the metal ground part 130 correspond to the antenna unit 120(2) and the resonance slot 132(2)) can also form another resonance structure.

[0069] Based on the above, through the above-mentioned wireless communication device 100, the above-mentioned antenna structure can further meet the high operating bandwidth of the 5G NR standard and the high isolation of the antenna unit in the sub-7GHz frequency band.

[0070] In summary, the wireless communication device provided by the present invention can greatly increase the isolation of the antenna unit by using the isolation slots between adjacent antenna units and the vertical arrangement of the antenna units. In addition, the wireless communication device provided by the present invention can also greatly increase the operating bandwidth of the antenna unit by using the resonance slots of the feeding lines of adjacent antenna units. In this way, the high operating bandwidth of the 5G NR standard and the high isolation of the antenna unit can be met in the sub-7GHz frequency band.

[0071] Although the present invention has been disclosed above by way of examples, it is not intended to limit the present invention. Any person skilled in the art within the scope of the present invention's concept can make some changes and modifications. Therefore, the protection scope of the present invention shall be subject to what is defined by the claims.

Claims

1. A wireless communication device, comprising: a substrate including a first surface and a second surface; an antenna structure including a first antenna unit and a second antenna unit, the first antenna unit and the second antenna unit being disposed on the first surface and perpendicular to each other, wherein the first antenna unit and the second antenna unit respectively include a first radiation portion, a second radiation portion, a third radiation portion, a feeding portion, and a feeding line, and the feeding line includes a first transmission line and a second transmission line that are perpendicular to each other and connected to each other, wherein the first transmission line of the feeding line is connected to the first radiation portion via the feeding portion; and a metal ground portion disposed on the second surface, wherein an isolation slot is provided on the metal ground portion at a position corresponding to the projection of the first antenna unit and the second antenna unit on the metal ground portion, the metal ground portion having a first edge and a second edge, wherein the first edge and the second edge are perpendicular to each other, and the first edge is perpendicular to the projection of a part of the first radiation portion and the third radiation portion of the first antenna unit toward the metal ground portion, and parallel to the projection of the second radiation portion and the other part of the third radiation portion of the first antenna unit toward the metal ground portion, the second edge is perpendicular to the projection of a part of the first radiation portion and the third radiation portion of the second antenna unit toward the metal ground portion, and parallel to the projection of the second radiation portion and the other part of the third radiation portion of the second antenna unit toward the metal ground portion; and a first resonance slot and a second resonance slot provided on the metal ground portion, wherein the first resonance slot is provided between the first edge and the projection of the second transmission line of the feeding line of the first antenna unit toward the metal ground portion, and wherein the second resonance slot is provided between the second edge and the projection of the second transmission line of the feeding line of the second antenna unit toward the metal ground portion, wherein the first resonance slot and the second resonance slot are L-shaped, wherein the isolation slot is rectangular, and the length of the isolation slot and the lengths of the first resonance slot and the second resonance slot are one-quarter of the wavelength of the center frequency of an operating frequency band of the first antenna unit and the second antenna unit.

2. The wireless communication device according to claim 1, wherein the lengths of the first edge and the second edge are one-half of the wavelength of the center frequency of the operating frequency band of the first antenna unit and the second antenna unit.

3. The wireless communication device according to claim 1, wherein the width of the isolation slot is 3.6 mm, and the widths of the first resonance slot and the second resonance slot are 1 mm, and the distance between the isolation slot and the projection of the first antenna unit and the second antenna unit on the metal ground portion is greater than 1 mm.

4. The wireless communication device according to claim 1, wherein the first radiating portion, the second radiating portion, and the third radiating portion resonate by themselves to generate a first resonance band, and the first resonance slot and the second resonance slot resonate with the first radiating portion, the second radiating portion, and the third radiating portion respectively to generate a second resonance band adjacent to the first resonance band.

5. The wireless communication device according to claim 1, wherein the first radiating portion, the second radiating portion, and the third radiating portion are inverted F-shaped, and the feeding line is L-shaped, wherein the isolation slot blocks signal transmission between the first antenna unit and the second antenna unit to increase an isolation degree between the first antenna unit and the second antenna unit.

6. The wireless communication device according to claim 1, wherein the wireless communication device includes a plurality of the antenna structures.

Images