Dipole antennas, polarized common antennas, and array antennas

Abstract

[Problem] To provide a dipole antenna, a polarization common antenna, and an array antenna suitable for configuring multilayer substrates or other three-dimensional circuits in the 28 GHz range or higher and equivalent high frequency ranges. [Solution] A dipole antenna, a polarized common antenna, and an array antenna each have an antenna section formed on a dielectric layer, and a pseudo-coaxial line formed on the dielectric layer and connected to the antenna section, and the pseudo-coaxial line has an external conductor and a signal line.

Description

Technology Field

[0001] The present invention relates to a dipole antenna, a polarized common antenna, and an array antenna that are desirable for a mobile communication base station antenna, and in particular, to a dipole antenna, a polarized common dipole antenna, and an array antenna that were difficult to realize in the past for frequencies of 28 GHz or higher allocated in 5G. Background Technology

[0002] In mobile wireless communication, the application of MIMO (Multi Input Multi Output) has become essential due to capacity expansion. Polarization MIMO using orthogonal polarization is used to realize MIMO.

[0003] To address this, mobile phone base station antennas use polarized common antennas.

[0004] The combined polarization antenna makes it possible to radiate two orthogonal polarizations from a single antenna, contributing to the miniaturization of base station antennas.

[0005] In the conventionally allocated SUB6 band, that is, the frequency band of 6 GHz or lower, polarization common antennas such as the dipole antenna described in Patent Document 2 or the patch antenna described in Patent Document 1 are known.

[0006] On the other hand, in the 28GHz band or higher millimeter wave bands allocated for 5G, dipole antennas are difficult to use, so patch antennas are being considered. Prior art literature

[0007] Japanese Patent Publication No. 2003-46326, Japanese Patent Publication No. 2014-39192, Japanese Patent No. 6341293, Japanese Patent No. 5638827 The problem to be solved

[0008] A dipole antenna needs to include a balun circuit for operation.

[0009] Conventional balun circuits are implemented, for example, using a dielectric substrate, and are configured on the premise that the substrate stands on its own.

[0010] In other words, in the SUB6 unit, the baluns for each polarized antenna can be configured as separate substrates, allowing for a self-standing structure.

[0011] However, in the 28GHz band, the wavelength is very short and the antenna structure becomes small and fine, so it is impossible to stand independently on the board alone, making it difficult to secure an independent structure like SUB6.

[0012] In addition, a dipole antenna as described in Patent Document 2 is difficult to realize on a multilayer substrate. In three-dimensional circuits such as multilayer substrates, the vertical direction (the direction in which the balun circuit is formed) is configured with a conductor by a through hole, but in the through hole, it is not possible to configure it in a flat plate (strip line structure) as in the conventional configuration example.

[0013] Typically, patch antennas can be realized due to the ease of design, as they are formed into three-dimensional structures using multilayer substrates. If it is a patch antenna as described in Patent Document 1, polarization can be shared using a three-dimensional circuit such as a multilayer substrate, but compared to a dipole antenna, the cross-polarization characteristics and isolation characteristics are poor.

[0014] Even in dipole antennas used in conjunction with patch antennas in a cooperative manner as described in Patent Documents 3 and 4, the cross-polarization characteristics and isolation characteristics are poor compared to dipole antennas. Furthermore, while the antenna described in Patent Document 3 takes into account unnecessary radiation from high-frequency elements, neither Patent Document 3 nor Patent Document 4 takes into account the influence of signal lines, so there is no concept similar to a pseudo-coaxial line.

[0015] Therefore, assuming a configuration on a multilayer substrate, it is necessary to examine the structure of a new polarization common dipole antenna including a balun circuit.

[0016] Accordingly, the present invention aims to realize a dipole antenna, a polarization common antenna, and an array antenna suitable for configuring a multilayer substrate or other three-dimensional circuit (LTCC, etc.) in the 28 GHz range or higher and a high frequency range equivalent thereto.

[0017] In addition, the present invention aims to realize a dipole antenna, a polarized common antenna, and an array antenna in a multilayer substrate or a three-dimensional circuit configuration equivalent thereto.

[0018] In addition, the present invention aims to provide a dipole antenna, a common polarization antenna, and an array antenna that are more desirable in terms of MIMO performance or beamforming performance by obtaining broadband and good isolation and cross-polarization characteristics compared to a patch antenna at frequencies of 28 GHz or higher allocated in 5G. means of solving the problem

[0019] The dipole antenna according to claim 1 of the present invention is,

[0020] having an antenna portion formed on a dielectric layer,

[0021] A pseudo-coaxial line formed in the dielectric layer and connected to the antenna portion is provided,

[0022] The above-mentioned pseudo-coaxial line is a dipole antenna characterized by having an outer conductor and a signal line.

[0023] The dipole antenna according to claim 2 of the present invention is,

[0024] It is a dipole antenna as described in claim 1, characterized in that the above-mentioned external conductor and the above-mentioned signal line are formed by a through hole.

[0025] The dipole antenna according to claim 3 of the present invention is,

[0026] The above signal line is a dipole antenna as described in either claim 1 or 2, characterized in that it is surrounded by three or more of the above external conductors.

[0027] The dipole antenna according to claim 4 of the present invention is,

[0028] The above signal line is,

[0029] It is positioned passing through the gap between the two antenna elements of the above antenna part and excites the above antenna part,

[0030] A dipole antenna as described in any one of claims 1 to 3, characterized in that one antenna element is positioned oppositely by a predetermined distance from the other antenna element and is connected to the other antenna element, and the other antenna element is grounded by the pseudo-coaxial line.

[0031] The dipole antenna according to claim 5 of the present invention is,

[0032] The above signal line is,

[0033] It is positioned passing through the gap between the two antenna elements of the above antenna part and excites the above antenna part,

[0034] The dipole antenna described in any one of claims 1 to 3 is characterized by having two antenna elements having the antenna portion that are spaced apart by a predetermined distance and facing each other, and having an open end on the side opposite to the side where the high-frequency current or the high-frequency current is supplied.

[0035] The dipole antenna according to claim 6 of the present invention is,

[0036] The above dielectric layer has a first dielectric layer and a second dielectric layer,

[0037] The above antenna portion is formed on the second dielectric layer, and

[0038] The dipole antenna described in any one of claims 1 to 5 is characterized in that at least a portion of the signal lines is formed on the first dielectric layer and forms a gap line.

[0039] The dipole antenna according to claim 7 of the present invention is,

[0040] The dipole antenna described in any one of claims 1 to 6 is characterized by having a transmission layer having a transmission line on the side opposite to the side where the antenna portion is formed among the dielectric layers.

[0041] The polarization common antenna according to claim 8 of the present invention is,

[0042] It is a polarization common antenna characterized by having two dipole antennas as described in any one of claims 1 to 7, wherein the two dipole antennas are orthogonal to each other.

[0043] The polarization common antenna according to claim 9 of the present invention is,

[0044] The two dipole antennas described above are polarization common antennas described in claim 8, characterized in that they are formed on different dielectric layers.

[0045] The array antenna according to claim 10 of the present invention is,

[0046] It is an array antenna characterized by having a distribution circuit or a synthesis circuit, having a plurality of dipole antennas described in any one of claims 1 to 7, or having a plurality of polarization common antennas described in claim 8 or 9. Effects of the invention

[0047] By the above configuration, the present invention obtains broadband electrical characteristics originating from a dipole antenna.

[0048] In addition, compared to conventional patch antennas, good cross-polarization identification characteristics and isolation characteristics are obtained, making it more desirable for polarization MIMO or beamforming. Brief explanation of the drawing

[0049] FIG. 1 shows an example of the configuration of a dipole antenna in one embodiment of the present invention. FIG. 2 shows an example of the configuration of a pseudo-coaxial line in one embodiment of the present invention. FIG. 3 shows an example of the configuration of a dipole antenna in one embodiment of the present invention. FIG. 4 shows an example of the configuration of a pseudo-coaxial line in one embodiment of the present invention. FIG. 5 shows an example of the configuration of a pseudo-coaxial line in one embodiment of the present invention. FIG. 6 shows an example of the configuration of a dipole antenna in one embodiment of the present invention. FIG. 7 shows an example of the configuration of a dipole antenna in one embodiment of the present invention. FIG. 8 shows an example of the configuration of a dipole antenna in one embodiment of the present invention. FIG. 9 shows an example of the configuration of a dipole antenna in one embodiment of the present invention. FIG. 10 shows an example of the configuration of a dipole antenna in one embodiment of the present invention. FIG. 11 shows an example of the configuration of a dipole antenna in one embodiment of the present invention. FIG. 12 shows an example of the configuration of a dipole antenna in one embodiment of the present invention. FIG. 13 shows an example of the configuration of a dipole antenna in one embodiment of the present invention. FIG. 14 shows an example of the configuration of a dipole antenna in one embodiment of the present invention. FIG. 15 shows an example of the configuration of a polarization common antenna in one embodiment of the present invention. FIG. 16 shows an example of the configuration of a polarization common antenna in one embodiment of the present invention. FIG. 17 shows an example of the configuration of a polarization common antenna in one embodiment of the present invention. FIG. 18 shows an example of the configuration of an array antenna in one embodiment of the present invention. FIG. 19 shows an example of the configuration of an array antenna in one embodiment of the present invention. Specific details for implementing the invention

[0050] FIG. 1 shows an example of the configuration of a related dipole antenna (100) in one embodiment of the present invention.

[0051] The dipole antenna (100) has an antenna portion (110) formed on a dielectric layer (300).

[0052] A pseudo-coaxial line (200) is formed in a dielectric layer (300) and connected to an antenna section (110). Additionally, the pseudo-coaxial line is connected to the antenna section, and "pseudo-coaxial line connected to the antenna section" means that an external conductor (210) is connected, and as described below, the signal line (220) is not necessarily limited to being electrically connected to the antenna section (110). Additionally, the pseudo-coaxial line is connected to the antenna section, and "pseudo-coaxial line connected to the antenna section" means that a pseudo-coaxial line having an external conductor and a signal line is connected to the same antenna element.

[0053] In this embodiment, the short balloon configuration described below is used.

[0054] FIG. 2 shows an example of the configuration of a pseudo-coaxial line in one embodiment of the present invention.

[0055] The pseudo-coaxial line (200) has an outer conductor (210) and a signal line (220).

[0056] In this embodiment, the outer conductor (210) and the signal line (220) are formed by through holes.

[0057] With this configuration, the formation of the external conductor (210) and the signal line (220) is facilitated.

[0058] In one embodiment, the frequency of the radio waves transmitted or received by the dipole antenna (100) is 28 GHz or higher. It may be carried out at 24.7 to 30.2 GHz, or at 24.7 GHz or higher.

[0059] With this configuration, it can also support 5G standards.

[0060] FIG. 3 shows an example of the configuration of a dipole antenna (100) in one embodiment of the present invention. FIG. 4 also shows an example of the configuration of a pseudo-coaxial line (200) in one embodiment of the present invention.

[0061] In this embodiment, three or more pseudo-coaxial lines (200) are connected to the antenna section (110).

[0062] And, the signal line (220) is arranged surrounded by three or more external conductors (210). "Arranged surrounded by external conductors (210)" means that, in a cross-section, more than half of the portion of the signal line (220) extending in the vertical direction is arranged within the plane connecting three or more external conductors (210) in the surrounding area. Accordingly, in addition to the configuration shown in FIG. 4, the configuration example of the pseudo-coaxial line (200) shown in FIG. 5 may also be used.

[0063] With this configuration, both the influence from the signal line (220) and the influence on the signal line (220) can be suppressed by the external conductor (210), and the influence from the outside, the influence to the outside, the cross-polarization identification, and the isolation characteristics are improved. That is, by adopting the structure of a pseudo-coaxial line (200), the characteristics of the antenna, etc., can be improved.

[0064] As shown in FIGS. 3 and 4, the dipole antenna (100) has a symmetry axis in a vertical direction at the center, and the outer conductor (210) and signal line (220) can also be arranged symmetrically with respect to the symmetry axis. In this case, the aforementioned characteristics are further improved. The same applies to the configuration shown in FIG. 5.

[0065] FIG. 6 shows an example of the configuration of a dipole antenna (100) in one embodiment of the present invention. In this embodiment, four outer conductors (210) surround one signal line (220).

[0066] The outer conductor (210) surrounding the signal line (220) may be five or more.

[0067] There may be multiple signal lines (220) connected to a single dipole element. With this configuration, precision in controlling the dipole antenna (100) can be improved.

[0068] Additionally, one external conductor (210) may be configured to belong to a plurality of similar coaxial lines (200). With this configuration, the influence between signal lines (220) can be efficiently suppressed by a small number of external conductors (210).

[0069] FIG. 7 schematically shows an example of the circuit configuration of a dipole antenna (100) in one embodiment of the present invention.

[0070] High-frequency voltage or high-frequency current is supplied to the signal line (220).

[0071] The signal line (220) is positioned to pass through the gap (G) between the two antenna elements (111) of the antenna section (110) and to excite the antenna section (110).

[0072] The signal line (220) is positioned opposite to one of the two antenna elements (111) of the antenna section (110) at a predetermined distance from the lower side of the antenna element (111), passes through the gap, and is connected to the other antenna element (111). Additionally, the other antenna element (111) is grounded by a pseudo-coaxial line, forming a short balun configuration. The connection of the signal line (220) to the antenna section (110) is preferably at the end of the antenna element (111).

[0073] Here, "grounded" includes not only direct grounding but also being connected to grounding terminals or wires, or being connected to terminals or similar devices for connecting to grounding terminals or wires.

[0074] In this embodiment, a return loss of -10dB or less is obtained at 24.7 to 30.2GHz.

[0075] FIG. 8 schematically shows an example of the circuit configuration of a dipole antenna (100) in one embodiment of the present invention.

[0076] High-frequency voltage or high-frequency current is supplied to the signal line (220).

[0077] The signal line (220) is positioned to pass through the gap (G) between the two antenna elements (111) of the antenna section (110) and to excite the antenna section (110).

[0078] The signal line (220) is positioned opposite to the two antenna elements (111) of the antenna section (110) at a predetermined distance from the lower side of the antenna elements (111), and the end of the side opposite to the side to which the high-frequency current is supplied is an open balun configuration that is not electrically connected to another circuit.

[0079] FIGS. 9 and FIGS. 10 schematically show an example of the configuration of a dipole antenna (100).

[0080] Figure 9 shows a short balloon configuration, and Figure 10 shows an open balloon configuration.

[0081] The dielectric layer (300) has a first dielectric layer (301) and a second dielectric layer (302).

[0082] An antenna portion (110) is formed on the second dielectric layer (302).

[0083] Additionally, at least a portion of the signal line (220) is formed on the first dielectric layer (301) to form a gap line (221). The gap line (221) supplies the necessary potential to the antenna part (110) by positioning the signal line (220) at a predetermined distance from the antenna part (110).

[0084] FIGS. 11 and 12 schematically show an example of the configuration of a dipole antenna (100).

[0085] Figure 11 shows a short balloon configuration, and Figure 12 shows an open balloon configuration.

[0086] In this embodiment, among the dielectric layers (300), there is a transmission layer (310) having a transmission line (230) on the side opposite to where the antenna part (110) is installed. In the transmission layer (310), a circuit required for the antenna can be configured.

[0087] As shown in FIG. 13, a short balun configuration having a second dielectric layer may be used, or as shown in FIG. 14, an open balun configuration having a second dielectric layer may be used.

[0088] FIG. 15 schematically illustrates an example of the configuration of a polarization common antenna (101) in one embodiment of the present invention.

[0089] The polarization common antenna (101) is equipped with two dipole antennas (100) as described so far, and the two dipole antennas (100) are orthogonal to each other.

[0090] In this configuration, where three or more pseudo-coaxial lines (200) are installed, the cross-polarization identification and the isolation characteristics between the two antenna sections (110) are particularly improved, and an isolation characteristic of about 25 dB is obtained along with a return loss of -10 dB at 24.7 to 30.2 GHz.

[0091] FIGS. 16 and 17 schematically illustrate an example of the configuration of a polarization common antenna (101) in one embodiment of the present invention.

[0092] Figure 16 shows a short balloon configuration, and Figure 17 shows an open balloon configuration.

[0093] A second dielectric layer (302) is formed on the first dielectric layer (301), and a third dielectric layer (303) is formed on the second dielectric layer (302).

[0094] Two dipole antennas (100) are formed on different dielectric layers (300). That is, one dipole antenna (100) is formed on the second dielectric layer (302), and another dipole antenna (100) orthogonal to this dipole antenna (100) is formed on the third dielectric layer (303).

[0095] If space permits, a plurality of dipole antennas (100) may be formed on the second dielectric layer (302) or the third dielectric layer (303).

[0096] With this configuration, two or more dipole antennas (100) can be easily designed and formed depending on the installation area or characteristics.

[0097] FIG. 18 shows an example of the configuration of an array antenna (102) in one embodiment of the present invention.

[0098] As shown in FIG. 19, the array antenna (102) has a distribution circuit (321) or a synthesis circuit (322). Additionally, it has a plurality of the polarization common antennas (101) described above.

[0099] In this embodiment, the distribution and synthesis unit (320) has a distribution circuit (321) and a synthesis circuit (322), and the distribution circuit (321) and the synthesis circuit (322) are connected to a plurality of polarized common antennas (101).

[0100] The array antenna (102) may be configured to have multiple dipole antennas (100) as described so far.

[0101] With the above configuration, broadband electrical characteristics originating from the dipole antenna are obtained, and compared to conventional patch antennas, good cross-polarization identification characteristics and isolation characteristics are obtained, making it very advantageous for polarization MIMO or beamforming.

[0102] In particular, since multilayer substrates can be used, routing of the power supply circuit can also be easily realized.

[0103] In addition, compared to patch antennas, cross-polarization is reduced, which not only enhances the MIMO effect but also allows for flexible changes in element directivity, such as widening or narrowing the beam width or lowering the side lobes, thereby providing a high degree of design freedom.

[0104] The present invention is not limited to the above embodiments and, needless to say, includes various embodiments within the scope that does not deviate from the spirit of the invention. Explanation of the symbols

[0105] 100; Dipole antenna 101; Polarized common antenna 102; Array antenna 110; Antenna section 111; antenna element 200; pseudo-coaxial line 210; outer conductor 220; signal line 221; Gap track 230; transmission line 300; dielectric layer 301; 1st dielectric layer 302; Second dielectric layer 303; Third dielectric layer 310; Transmission layer 320; Distribution composite part 321; Distribution circuit 322; Synthetic circuit G; gap

Claims

Claim 1 A dipole antenna having an antenna portion formed on a dielectric layer, a pseudo-coaxial line formed on the dielectric layer and connected to the antenna portion, wherein the pseudo-coaxial line has an external conductor and a signal line, wherein the signal line is arranged to pass through a gap between two antenna elements having the antenna portion and excites the antenna portion, wherein the signal line is positioned opposite to one of the antenna elements by a predetermined distance and is connected only to the other antenna element, and wherein the other antenna element is grounded by the pseudo-coaxial line. Claim 2 A dipole antenna according to claim 1, characterized in that the outer conductor and the signal line are formed by a through hole. Claim 3 A dipole antenna according to claim 1 or 2, characterized in that the signal line is arranged surrounded by three or more of the outer conductors. Claim 4 A dipole antenna according to claim 1 or 2, characterized in that the signal line is spaced apart by a predetermined distance from the two antenna elements having the antenna part, and the end opposite to the side where a high-frequency current of 28 GHz or higher is supplied is open. Claim 5 A dipole antenna according to claim 1 or 2, wherein the dielectric layer has a first dielectric layer and a second dielectric layer, the antenna portion is formed on the second dielectric layer, and at least a portion of the signal lines is formed on the first dielectric layer and forms a gap line. Claim 6 A dipole antenna according to claim 1 or 2, characterized in that it has a transmission layer having a transmission line on the side opposite to the side where the antenna portion is formed among the dielectric layers. Claim 7 A polarization common antenna characterized by having two dipole antennas as described in claim 1, wherein the two dipole antennas are orthogonal to each other. Claim 8 A polarization common antenna according to claim 7, characterized in that the two dipole antennas are formed on different dielectric layers. Claim 9 An array antenna characterized by having a distribution circuit or a synthesis circuit, having a plurality of dipole antennas as described in claim 1 or 2, or having a plurality of polarization common antennas as described in claim 7 or 8. Claim 10 delete

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