Antenna Module

Abstract

An antenna module according to an embodiment of the present invention includes a substrate including a ground portion and a dielectric portion, a first antenna formed to have a length corresponding to a first frequency band and disposed on one side of a first edge of the substrate, a second antenna formed to have a length corresponding to the second frequency band and disposed on one side of a second edge of the substrate, and a stub disposed on one side of the first edge or one side of the second edge between the first antenna and the second antenna, the stub being spaced a first distance from the first antenna and a second distance from the second antenna, the first distance and the second distance being set based on a first wavelength band and a second wavelength band corresponding to the first frequency band and the second frequency band.

Description

[Technical field]

[0001] The embodiment relates to an antenna module. [Background technology]

[0002] Generally, research is being conducted to improve the performance of antenna devices in communication terminals. This is because the antenna devices in communication terminals are essentially responsible for transmitting and receiving signals. Accordingly, MIMO (Multiple-Input Multiple-Output) antenna devices have recently been proposed as antenna devices to be installed in communication terminals. At this time, the MIMO antenna device is equipped with a number of antenna elements. Such MIMO antenna devices can connect to various communication networks by transmitting and receiving signals in a certain frequency band through the antenna elements.

[0003] However, when the MIMO antenna device is operated, electromagnetic mutual coupling occurs between the antenna elements, which may cause a degradation in the performance of the communication terminal.

[0004] In order to reduce mutual interference between antennas, methods such as adjusting the distance between antenna elements, inserting a decoupling circuit, and using a suspended line design are used.

[0005] However, in the case of adjusting the separation distance, there is a problem that it is difficult to miniaturize the antenna design, and in the case of inserting a decoupling circuit or a suspended line design, only narrowband frequencies are possible, making it difficult to apply to multi-band and broadband (e.g. UWB).

[0006] For this reason, a method for suppressing electromagnetic mutual coupling between antenna elements in a MIMO antenna device is required. Summary of the Invention [Problem to be solved by the invention]

[0007] The embodiment is intended to provide an antenna module capable of improving isolation between a plurality of antennas included in the antenna module.

[0008] The problems to be solved by the examples are not limited to those described above, and may also include the objectives and effects that can be grasped from the means for solving the problems and embodiments described below. [Means for solving the problem]

[0009] An antenna module according to an embodiment of the present invention includes a substrate including a ground portion and a dielectric portion, a first antenna formed to have a length corresponding to a first frequency band and disposed on one side of a first edge of the substrate, a second antenna formed to have a length corresponding to a second frequency band and disposed on one side of a second edge of the substrate, and a stub disposed on one side of the first edge or one side of the second edge between the first antenna and the second antenna, the stub being spaced a first distance from the first antenna and a second distance from the second antenna, the first distance and the second distance being set based on a first wavelength band and a second wavelength band corresponding to the first frequency band and the second frequency band.

[0010] The first antenna and the second antenna may be disposed on an upper end of the dielectric portion.

[0011] The stub may be disposed on an upper end of the dielectric portion and connected to the ground portion.

[0012] The first frequency band and the second frequency band may be the same frequency band.

[0013] The first distance may be a distance from a first point, which is a center of an area where the first antenna and an edge of the ground portion intersect, to a second point, which is a center of an area where the stub and the ground portion intersect.

[0014] The second distance may be a distance from a third point, which is a center of an area where the second antenna and an edge of the ground portion intersect, to a second point, which is a center of an area where the stub and the ground portion intersect.

[0015] The first distance may be between 1 / 8 and 1 times the first wavelength band.

[0016] The first distance may be between 1 / 8 and 7 / 8 times the first wavelength band.

[0017] The first distance may be between 1 / 4 and 3 / 4 times the first wavelength band.

[0018] The first distance may be one-half the first wavelength band.

[0019] An antenna module according to an embodiment of the present invention includes a substrate including a ground portion and a dielectric portion, a first antenna formed to have a length corresponding to a first frequency band and disposed on one side of a first edge of the substrate, a second antenna formed to have a length corresponding to a second frequency band and disposed on one side of a second edge of the substrate, and a stub disposed on one side of the first edge or one side of the second edge between the first antenna and the second antenna, the stub being spaced a first distance from the first antenna and a second distance from the second antenna, the first distance being set based on an electric field of the first antenna.

[0020] The stub may be disposed at a null point of an electric field of the first antenna. Effect of the Invention

[0021] According to the embodiment, it is possible to improve the isolation between multiple antennas mounted on one substrate.

[0022] In addition, the performance of multiple antennas mounted on one substrate can be improved.

[0023] In addition, the antenna module can be made smaller.

[0024] The various yet beneficial advantages and effects of the present invention are not limited to the above, but will be more easily understood in the course of describing specific embodiments of the present invention. [Brief description of the drawings]

[0025] [Figure 1] 1 is a schematic diagram of an antenna module according to an embodiment of the present invention; [Diagram 2] 2 is a diagram illustrating a cross section taken along line aa in FIG. 1. [Diagram 3] 2 is a diagram illustrating a cross section taken along line bb in FIG. 1; [Figure 4] 4 is a diagram for explaining a first distance and a second distance according to an embodiment of the present invention. [Figure 5a] 1 is a diagram for explaining an S parameter simulation result according to an embodiment of the present invention. [Figure 5b] 1 is a diagram for explaining an S parameter simulation result according to an embodiment of the present invention. [Figure 6] 1 is a diagram illustrating antenna performance according to an embodiment of the present invention; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0027] However, the technical concept of the present invention is not limited to the described embodiments, but may be embodied in various different forms, and one or more of the components of the embodiments may be selectively combined or substituted within the scope of the technical concept of the present invention.

[0028] Furthermore, terms (including technical and scientific terms) used in the embodiments of the present invention may be interpreted in a manner that is commonly understood by a person having ordinary skill in the art to which the present invention belongs, unless otherwise clearly defined and described, and commonly used terms, such as terms defined in a dictionary, may be interpreted in light of the contextual meaning of the relevant art.

[0029] Furthermore, the terms used in the embodiments of the present invention are intended to describe the embodiments and are not intended to limit the present invention.

[0030] In this specification, the singular can include the plural unless otherwise specified in the context, and when it is stated that "A and (and) at least one (or more) of B and C" it can include one or more of all possible combinations of A, B, and C.

[0031] Additionally, terms such as first, second, A, B, (a), (b), etc. may be used to describe components of embodiments of the present invention.

[0032] Such terms are merely used to distinguish a component from other components, and are not intended to limit the nature, order, or sequence of the components.

[0033] Furthermore, when a component is described as being "coupled," "coupled," or "connected" to another component, it includes not only cases where the component is directly coupled, coupled, or connected to the other component, but also cases where the component is "coupled," "coupled," or "connected" by yet another component between the component and the other component.

[0034] In addition, when described as being formed or disposed "above or below" each component, "above" or "below" includes not only the case where two components are in direct contact with each other, but also the case where one or more other components are formed or disposed between the two components. In addition, when described as "above or below," it can include not only the upper direction but also the lower direction based on one component.

[0035] Fig. 1 is a schematic diagram of an antenna module according to an embodiment of the present invention, Fig. 2 is a diagram illustrating a cross section taken along line aa in Fig. 1, and Fig. 3 is a diagram illustrating a cross section taken along line bb in Fig. 1.

[0036] Referring to FIG. 1, an antenna module according to an embodiment of the present invention may include a substrate 100 , a first antenna 200 , a second antenna 300 and a stub 400 .

[0037] The substrate 100 may include a ground portion 110 and a dielectric portion 120 .

[0038] The ground part 110 may be made of a conductor. The ground part 110 may be formed of at least one ground layer. For example, the ground part 110 may be formed of one to four ground layers, but is not limited thereto. The ground part 110 may be formed of four or more ground layers. When the ground part 110 is formed of a plurality of ground layers, the ground part 110 may be embodied in a structure in which a plurality of ground layers are stacked. When a plurality of ground layers are stacked, the ground part 110 may include at least one via hole penetrating the plurality of ground layers. Circuit elements for transmitting and receiving signals from the antenna may be disposed on an upper surface of the ground part 110.

[0039] The dielectric part 120 may be made of a dielectric material. For example, the dielectric part 120 may be made of an FR4 epoxy dielectric. The dielectric part 120 may be formed of at least one dielectric layer. For example, the dielectric part 120 may be formed of one to four dielectric layers, but is not limited thereto. The dielectric part 120 may be formed of four or more dielectric layers. When the dielectric part 120 is formed of a plurality of dielectric layers, the dielectric part 120 may be embodied as a structure in which a plurality of dielectric layers are stacked.

[0040] The ground portion 110 and the dielectric portion 120 may be disposed on each other's side. For example, as shown in FIG. 1 to FIG. 3, the inner surface of the dielectric portion 120 in the shape of "┐" and The outer surfaces of the grounding portions 110 having the shape of TIFF0007673253000001.tif11121 may be arranged in contact with each other.

[0041] The first antenna 200 may operate in a first frequency band. That is, the first antenna 200 may transmit and receive signals in the first frequency band. According to one embodiment, the first frequency band may be a frequency band for UWB (ultra wideband) communication. For example, the first frequency band may be a frequency band of 3.1 to 10.6 GHz. According to another embodiment, the first frequency band may be a frequency band for Bluetooth communication and / or a frequency band for Wi-Fi communication. For example, the first frequency band may be a frequency band of 2.4 GHz.

[0042] The first antenna 200 may be formed to have a length corresponding to a first frequency band. The length of the first antenna 200 may be calculated based on Equation 1 below.

[0043] [Mathematical formula 1] λ 1 =c / f 1 where f 1 denotes the frequencies included in the first frequency band, c denotes the speed of light, and λ 1 means a wavelength included in a wavelength range corresponding to the first frequency band.

[0044] The length of the first antenna 200 may be set to correspond to the wavelength. According to one embodiment, the length of the first antenna 200 may be 0.25 times the wavelength (i.e., the length of the first antenna 200 is λ 1 As another example, the length of the first antenna 200 may be equal to the wavelength (i.e., the length of the first antenna 200 is λ 1 As another example, the length of the first antenna 200 may be 0.5 times the wavelength (i.e., the length of the first antenna 200 is λ 1 / 2).

[0045] The first antenna 200 may be disposed on an edge of the substrate 100. The first antenna 200 may be disposed on one side of the first edge of the substrate 100. The first antenna 200 may be disposed on an upper end of a dielectric layer disposed on one side of the first edge of the substrate 100.

[0046] The second antenna 300 may operate in a second frequency band. That is, the second antenna 300 may transmit and receive signals in the second frequency band. According to one embodiment, the second frequency band may be a frequency band for UWB communication. For example, the second frequency band may be a frequency band of 3.1 to 10.6 GHz. According to another embodiment, the second frequency band may be a frequency band for Bluetooth communication and / or a frequency band for Wi-Fi communication. For example, the second frequency band may be a frequency band of 2.4 GHz.

[0047] The second antenna 300 may be formed to have a length corresponding to the second frequency band. The length of the second antenna 300 may be calculated based on Equation 2 below.

[0048] [Mathematical formula 2] λ 2 =c / f 2 where f 2 denotes the frequencies included in the second frequency band, c denotes the speed of light, and λ 2 means a wavelength included in the wavelength region corresponding to the second frequency band.

[0049] The length of the second antenna 300 may be set to correspond to the wavelength. According to one embodiment, the length of the second antenna 300 may be 0.25 times the wavelength (i.e., the length of the second antenna 300 is λ 2 As another example, the length of the second antenna 300 may be equal to the wavelength (i.e., the length of the second antenna 300 is λ 2 As another example, the length of the second antenna 300 may be 0.5 times the wavelength (i.e., the length of the second antenna 300 is λ 2 / 2).

[0050] The second antenna 300 may be disposed on an edge of the substrate 100. The second antenna 300 may be disposed on one side of the second edge of the substrate 100. The second antenna 300 may be disposed on an upper end of the dielectric portion 120 disposed on one side of the second edge of the substrate 100.

[0051] The first frequency band in which the first antenna 200 operates and the second frequency band in which the second antenna 300 operates may be the same frequency band. According to an embodiment, the first antenna 200 and the second antenna 300 may be antennas performing UWB communication. Thus, the first frequency band and the second frequency band may be frequency bands for UWB communication. According to another embodiment, the first antenna 200 and the second antenna 300 may be antennas performing Bluetooth communication. Thus, the first frequency band and the second frequency band may be frequency bands for Bluetooth communication. According to another embodiment, the first antenna 200 and the second antenna 300 may be antennas performing Wi-Fi communication. Thus, the first frequency band and the second frequency band may be frequency bands for Wi-Fi communication. According to another embodiment, the first antenna 200 may be an antenna performing Bluetooth communication, and the second antenna 300 may be an antenna performing Wi-Fi communication. The first frequency band and the second frequency band may be a frequency band in the 2.4 GHz band. According to another embodiment, the first antenna 200 may be an antenna for performing Wi-Fi communication, and the second antenna 300 may be an antenna for performing Bluetooth communication. The first and second frequency bands may be 2.4 GHz frequency bands.

[0052] The stub 400 may operate to eliminate interference due to mutual coupling between the first antenna 200 and the second antenna 300 .

[0053] The shape and length of the stub 400 may be designed based on the first and second frequency bands of the first and second antennas 200 and 300, the dielectric constant of the dielectric portion 120, and the like.

[0054] The stub 400 may be disposed between the first antenna 200 and the second antenna 300. The stub 400 may be disposed on one side of the first edge or on one side of the second edge. The stub 400 may be disposed on one side of the first edge between the first antenna 200 and the second antenna 300. The stub 400 may be disposed on one side of the second edge between the first antenna 200 and the second antenna 300.

[0055] The stub 400 may be disposed at an upper end of the dielectric portion 120. That is, the stub 400 may be disposed at an upper end of the dielectric portion 120 such as the first antenna 200 and the second antenna 300. The stub 400 may be disposed at an upper end of the dielectric portion 120 disposed on one side of a first edge between the first antenna 200 and the second antenna 300. The stub 400 may be disposed at an upper end of the dielectric portion 120 disposed on one side of a second edge between the first antenna 200 and the second antenna 300.

[0056] The stub 400 may be spaced a first distance from the first antenna 200. The first distance may be set based on a first wavelength band corresponding to a first frequency band. The first distance may be set based on a radiation pattern of the first antenna 200. The stub 400 may be located at a null point of the radiation pattern of the first antenna 200.

[0057] The stub 400 may be spaced a second distance from the second antenna 300. The second distance may be set based on a second wavelength band corresponding to a second frequency band. The second distance may be set based on a radiation pattern of the second antenna 300. The stub 400 may be located at a null point of the radiation pattern of the second antenna 300.

[0058] As described above, since the first and second frequency bands may be the same frequency band, the first and second distances may be set based on the same wavelength band. Also, since the first and second antennas 200 and 300 may operate in the same frequency band, the first and second distances may be set based on the same radiation pattern.

[0059] The first distance and the second distance will be described in detail below with reference to the drawings.

[0060] FIG. 4 is a diagram for explaining a first distance and a second distance according to an embodiment of the present invention.

[0061] The first distance d1 may be a distance between a first point p1 of the first antenna 200 and a second point p2 of the stub 400. The first point p1 may refer to the center of an area where an edge of the ground portion 110 and the first antenna 200 intersect. The second point p2 may refer to the center of an area where an edge of the ground portion 110 and the stub 400 intersect. The first distance d1 may refer to a distance connecting the first point p1 and the second point p2 along the edge of the ground portion 110.

[0062] The second distance d2 may be a distance between a third point p3 of the second antenna 300 and a second point p2 of the stub 400. The third point p3 may refer to a center of an area where an edge of the ground portion 110 and the second antenna 300 intersect. The second point p2 may refer to a center of an area where an edge of the ground portion 110 and the stub 400 intersect. The second distance d2 may refer to a distance connecting the third point p3 and the second point p2 along the edge of the ground portion 110.

[0063] According to the first embodiment of the present invention, the first distance d1 may be 1 / 8 to 1 times the first wavelength band. The first distance d1 may be 1 / 8 to 1 times the wavelength included in the first wavelength band. Also, the second distance d2 may be 1 / 8 to 1 times the second wavelength band. The second distance d2 may be 1 / 8 to 1 times the wavelength included in the second wavelength band. Since the first frequency band and the second frequency band may be the same frequency band, the first distance d1 and the second distance d2 may be set to 1 / 8 to 1 times the same wavelength band. Since the first frequency band and the second frequency band may be the same frequency band, the first distance d1 and the second distance d2 may be set to 1 / 8 to 1 times the same wavelength band.

[0064] According to the first embodiment of the present invention, the first distance d1 may be 1 / 8 to 7 / 8 times the first wavelength band. The first distance d1 may be 1 / 8 to 7 / 8 times the wavelength included in the first wavelength band. Also, the second distance d2 may be 1 / 8 to 7 / 8 times the second wavelength band. The second distance d2 may be 1 / 8 to 7 / 8 times the wavelength included in the second wavelength band. Since the first frequency band and the second frequency band may be the same frequency band, the first distance d1 and the second distance d2 may be set to 1 / 8 to 7 / 8 times the same wavelength band. Since the first frequency band and the second frequency band may be the same frequency band, the first distance d1 and the second distance d2 may be set to 1 / 8 to 7 / 8 times the same wavelength. As an example, the first distance d1 may be set to 1 / 8 times the wavelength, and the second distance d2 may be set to 7 / 8 times the wavelength.

[0065] According to the first embodiment of the present invention, the first distance d1 may be 1 / 4 to 3 / 4 times the first wavelength band. The first distance d1 may be 1 / 4 to 3 / 4 times the wavelength included in the first wavelength band. Also, the second distance d2 may be 1 / 4 to 3 / 4 times the second wavelength band. The second distance d2 may be 1 / 4 to 3 / 4 times the wavelength included in the second wavelength band. Since the first frequency band and the second frequency band may be the same frequency band, the first distance d1 and the second distance d2 may be set to 1 / 4 to 3 / 4 times the same wavelength band. Since the first frequency band and the second frequency band may be the same frequency band, the first distance d1 and the second distance d2 may be set to 1 / 4 to 3 / 4 times the same wavelength. As an example, the first distance d1 may be set to 1 / 4 times the wavelength, and the second distance d2 may be set to 3 / 4 times the wavelength.

[0066] According to the first embodiment of the present invention, the first distance d1 may be 1 / 2 times the first wavelength band. The first distance d1 may be 1 / 2 times the wavelength included in the first wavelength band. Also, the second distance d2 may be 1 / 2 times the second wavelength band. The second distance d2 may be 1 / 2 times the wavelength included in the second wavelength band. Since the first frequency band and the second frequency band may be the same frequency band, the first distance d1 and the second distance d2 may be set to 1 / 2 times the same wavelength band. Since the first frequency band and the second frequency band may be the same frequency band, the first distance d1 and the second distance d2 may be set to 1 / 2 times the same wavelength. As an example, the first distance d1 may be set to 1 / 2 times the wavelength, and the second distance d2 may be set to 1 / 2 times the wavelength. In this case, the first distance d1 and the second distance d2 may be the same.

[0067] As in the embodiment of the present invention, when the stub 400 is disposed in the antenna module, it is possible to significantly reduce the influence of the current caused by the direct coupling between the first antenna 200 and the second antenna 300. That is, the current generated in each antenna is concentrated in the stub 400, so that the interference between the antennas can be reduced.

[0068] In particular, when the first distance d1 and the second distance d2 are set as above, the stub 400 can be disposed in an area where the electric field of each antenna is weak or in a null area where the electric field is hardly affected, so that the current concentration in the stub 400 can be significantly increased and the degree of isolation between the two antennas can be significantly improved, which can lead to miniaturization of the antenna module.

[0069] 5a and 5b are diagrams for explaining S-parameter simulation results according to an embodiment of the present invention, and FIG 6 is a diagram for explaining antenna performance according to an embodiment of the present invention.

[0070] 5a, 5b and 6, the frequency band of UWB communication is assumed to be 6.24 to 8.24 GHz, and the simulation was performed based on an impedance bandwidth of VSWR 2: 1. Fig. 5a shows the simulation result of a conventional antenna module, and Fig. 5b shows the simulation result of an antenna module according to an embodiment of the present invention.

[0071] 5a, when two antennas in a conventional antenna module operate in the UWB band, the isolation characteristics between the first and second antennas are poor. Due to the poor isolation characteristics, not only are the antennas unable to provide normal performance in the 6.24~8.24GHz frequency band, but it can also be seen that electromagnetic interference between the antennas is severe.

[0072] On the other hand, referring to Fig. 5b, it can be seen that the antenna module according to the embodiment of the present invention has excellent isolation characteristics between the first and second antennas when the two antennas operate in the UWB band. The stubs arranged at a predetermined distance (first distance and second distance) between the first and second antennas act as a low pass filter (LPF), improving the isolation (S21) by about 20dB compared to the conventional antenna module (approximately -10dB for the conventional antenna module and approximately -30dB for the antenna module of the present invention).

[0073] 6, it can be seen that the performance of the first and second antennas is improved when the stub according to the embodiment of the present invention is present. When the stub is present, that is, the performance of the first and second antennas of the antenna module according to the embodiment of the present invention is improved by an average of 4 to 13% compared to the performance of the first and second antennas of the conventional antenna module. In addition, the peak value of the conventional antenna module is about 3 dBi, whereas the peak value of the antenna module according to the embodiment of the present invention is about 4 dBi, which is an improvement of about 1 dB in performance.

[0074] The above description is centered on the embodiment, but it is merely illustrative and does not limit the present invention. Those skilled in the art will understand that various modifications and applications not exemplified above are possible within the scope of the essential characteristics of the present embodiment. For example, each component specifically illustrated in the embodiment can be modified and implemented. Differences related to such modifications and applications should be interpreted as being included in the scope of the present invention defined in the appended claims.

Claims

1. a substrate including a ground portion and a dielectric portion; a first antenna having a length corresponding to a first frequency band and disposed on one side of a first edge of the substrate; a second antenna having a length corresponding to a second frequency band and disposed on one side of a second edge of the substrate; a stub disposed on one side of the first edge or one side of the second edge between the first antenna and the second antenna, the stub is spaced apart from the first antenna by a first distance and spaced apart from the second antenna by a second distance; the first distance and the second distance are set based on a first wavelength band and a second wavelength band corresponding to the first frequency band and the second frequency band, the ground portion and the dielectric portion are disposed on either side of each other; An antenna module, wherein the stub is positioned at an upper end of the dielectric portion so as to abut against an outer surface of the dielectric portion and an outer surface of the ground portion.

2. The antenna module of claim 1 , wherein the first antenna and the second antenna are disposed on an upper end of the dielectric portion.

3. The antenna module according to claim 1 , wherein the stub is coupled to the ground portion.

4. The antenna module according to claim 1 , wherein the first frequency band and the second frequency band are the same frequency band.

5. 2. The antenna module of claim 1, wherein the first distance is a distance from a first point that is a center of an area where the first antenna and an edge of the ground portion intersect to a second point that is a center of an area where the stub and the ground portion intersect.

6. 2. The antenna module of claim 1, wherein the second distance is a distance from a third point, which is a center of an area where the second antenna and an edge of the ground portion intersect, to a second point, which is a center of an area where the stub and the ground portion intersect.

7. The antenna module according to claim 1 , wherein the first distance is 1 / 8 to 1 times the first wavelength band.

8. The antenna module according to claim 1 , wherein the first distance is 1 / 8 to 7 / 8 times the first wavelength band.

9. The antenna module according to claim 1 , wherein the first distance is between ¼ and ¾ times the first wavelength band.

10. The antenna module of claim 1 , wherein the first distance is ½ times the first wavelength band.

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