antenna module

Abstract

An antenna module is provided. A matching circuit has first to fourth ports. A first high-frequency circuit transmits and receives a high-frequency signal to and from the first port via a first transmission line. The second port is connected to a second transmission line. The third port and the fourth port are connected to a first radiating element via a third transmission line and a fourth transmission line, respectively. The matching circuit distributes and outputs a high-frequency signal input to the first port to the third port and the fourth port, and combines and outputs a high-frequency signal reflected by the first radiating element and input to the third port and the fourth port to the second port. The second transmission line is longer than any one of the first transmission line, the third transmission line, and the fourth transmission line. According to these configurations, even in a quasi-millimeter wave band, a millimeter wave band, or the like, unnecessary re-input of a high-frequency signal to a radiating element can be suppressed.

Description

TECHNICAL FIELD

[0001] The present application relates to an antenna module. BACKGROUND

[0002] A circularly polarized wave patch antenna that radiates a circularly polarized wave by combining a rectangular patch antenna and a hybrid circuit is known (see Patent Document 1). The hybrid circuit is a circuit that combines four transmission paths having an electrical length of 1 / 4 wavelength in a bridge shape. The hybrid circuit divides and outputs a signal input to an input port from two output ports with a phase difference of 90°. The hybrid circuit has an isolation port that is independent of the input and output of the signal. The isolation port is terminated with a resistive element.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2004-221965

[0004] A high-frequency signal that is reflected by the patch antenna and returned to the hybrid circuit is synthesized by the hybrid circuit and output to the isolation port. If the high-frequency signal output to the isolation port is reflected and input again to the isolation port, the high-frequency signal input again is input again to the patch antenna from the two output ports. The phase relationship of the high-frequency signal input again to the patch antenna from the two output ports is different from the phase relationship of the high-frequency signal input from the input port and supplied to the patch antenna from the two output ports. Therefore, the circularity (axial ratio) of the circularly polarized wave radiated from the patch antenna decreases. In general, a non-reflective termination resistance is connected to the isolation port so that the signal output to the isolation port is not reflected and input again to the isolation port.

[0005] If the frequency band of the radio wave radiated from the patch antenna is a quasi-millimeter wave band or a millimeter wave band of 20 GHz or more, it is difficult to achieve a non-reflective termination with a chip resistive element or the like. SUMMARY

[0006] An object of the present application is to provide an antenna module that can suppress the input again of an unnecessary high-frequency signal to a radiating element even in a quasi-millimeter wave band, a millimeter wave band, or the like.

[0007] According to one aspect of the present application, there is provided an antenna module having:

[0008] a circuit that combines a first port, a second port, a third port, and a fourth port;

[0009] a first transmission line, a second transmission line, a third transmission line, and a fourth transmission line that are connected to the first port, the second port, the third port, and the fourth port, respectively,

[0010] a first high-frequency circuit connected to the first port via the first transmission line, and performing at least one of transmission and reception of a high-frequency signal to and from the first port via the first transmission line; and

[0011] at least one first radiating element connected to the third port and the fourth port via the third transmission line and the fourth transmission line, respectively,

[0012] the distribution-combining circuit distributes and outputs a high-frequency signal input to the first port to the third port and the fourth port, combines a high-frequency signal reflected by the first radiating element and input to the third port and the fourth port, and outputs the combined high-frequency signal to the second port,

[0013] the second transmission line is longer than any one of the first transmission line, the third transmission line, and the fourth transmission line.

[0014] According to another aspect of the present application, there is provided an antenna module having:

[0015] a distribution-combining circuit having a first port, a second port, a third port, and a fourth port;

[0016] first, second, third, and fourth transmission lines connected to the first, second, third, and fourth ports, respectively;

[0017] a first high-frequency circuit connected to the first port via the first transmission line, and performing at least one of transmission and reception of a high-frequency signal to and from the first port via the first transmission line; and

[0018] two external connection terminals connected to the third port and the fourth port, respectively,

[0019] the distribution-combining circuit distributes and outputs a high-frequency signal input to the first port to the third port and the fourth port, combines a high-frequency signal reflected by a radiating element and input to the third port and the fourth port, and outputs the combined high-frequency signal to the second port, the radiating element being connected to the external connection terminals,

[0020] the second transmission line is longer than any one of the first transmission line, the third transmission line, and the fourth transmission line.

[0021] If the second transmission line is lengthened, the amount of attenuation of the high frequency signal that reciprocates in the second transmission line increases. Therefore, the signal level of the unnecessary high frequency signal that is reflected by the radiating element and output to the second port becomes small when the unnecessary high frequency signal reciprocates in the second transmission line and is input to the radiating element again. As a result, the input of the unnecessary high frequency signal to the radiating element again can be suppressed. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 is a plan view of the antenna module of the first embodiment.

[0023] Figure 2 is a cross-sectional view taken on the dotted line 2-2 of Figure 1

[0024] Figure 3 is a plan view of the antenna module of the second embodiment.

[0025] Figure 4 is a cross-sectional view of the first transmission line and the second transmission line of the antenna module of the third embodiment.

[0026] Figure 5 is a plan view of the antenna module of the fourth embodiment.

[0027] Figure 6 is a plan view of the antenna module of the fifth embodiment.

[0028] Figure 7 is a view showing the positional relationship in the thickness direction of the transmission line, the radiating element, and the like that constitute the antenna module of the sixth embodiment.

[0029] Figure 8 is a view showing the positional relationship in the thickness direction of the transmission line, the radiating element, and the like that constitute the antenna module of the seventh embodiment.

[0030] Figure 9 is a view showing the positional relationship in the thickness direction of the transmission line, the radiating element, and the like that constitute the antenna module of the eighth embodiment.

[0031] Figure 10 is a view showing the positional relationship in the thickness direction of the transmission line, the radiating element, and the like that constitute the antenna module of the ninth embodiment.

[0032] Figure 11A and Figure 11B is a view showing the positional relationship in the thickness direction of the transmission line, the radiating element, and the like that constitute the antenna module of the tenth embodiment, and the external first radiating element. DETAILED DESCRIPTION

[0033] [First Embodiment]

[0034] Referring to​Figure 1 and Figure 2 The antenna module of the first embodiment will be described.

[0035] Figure 1 This is a top view of the antenna module 10 of the first embodiment. The antenna module 10 of the first embodiment includes: a distribution and combining circuit 20 disposed on a substrate 40, a first transmission line 21, a second transmission line 22, a third transmission line 23, a fourth transmission line 24, and a first radiating element 31 and a high-frequency circuit element 50 mounted on the substrate 40.

[0036] The distribution and combining circuit 20 is a 90° hybrid circuit with a first port P1, a second port P2, a third port P3, and a fourth port P4, comprising four transmission lines constituting a bridging circuit. A high-frequency circuit element 50 is connected to the first port P1 of the distribution and combining circuit 20 via the first transmission line 21. The high-frequency circuit element 50 includes a first high-frequency circuit that performs at least one of transmitting a high-frequency signal to the first port P1 and receiving a high-frequency signal from the first port P1.

[0037] The second port P2 of the distribution and synthesis circuit 20 is connected to the second transmission line 22. The third port P3 is connected to the power supply point 32A of the first radiating element 31 via the third transmission line 23, and the fourth port P4 is connected to another power supply point 32B of the first radiating element 31 via the fourth transmission line 24. The characteristic impedances of the first transmission line 21, the second transmission line 22, the third transmission line 23, and the fourth transmission line 24 are the same, for example, 50Ω.

[0038] The characteristic impedance of the transmission line connecting the first port P1 and the second port P2, and the transmission line connecting the third port P3 and the fourth port P4 in the four transmission lines of the distribution and synthesis circuit 20 are the same as the characteristic impedance of the first transmission line 21, etc. The characteristic impedance of the transmission line connecting the first port P1 and the third port P3, and the transmission line connecting the second port P2 and the fourth port P4, is half the characteristic impedance of the first transmission line 21, etc. 1 / 2 In addition, the electrical length of the four transmission lines of the distribution and synthesis circuit 20 at the resonant frequency of the first radiating element 31 is 1 / 4 of the wavelength.

[0039] The first radiating element 31 is formed of a conductor plate or conductor film, and is connected to a grounding conductor disposed on the substrate 40. Figure 2 Together with the ground conductor 42, it operates as a patch antenna. Two imaginary straight lines connecting each of the two power supply points 32A and 32B to the center of the first radiating element intersect at right angles. The first radiating element 31 resonates at a frequency, for example, above 20 GHz in the quasi-millimeter wave band or millimeter wave band.

[0040] The following describes the transmitting operation of this antenna module.

[0041] The distribution and synthesis circuit 20 distributes the high-frequency signal input to the first port P1 to the third port P3 and the fourth port P4, outputting them with a 90° phase difference. More specifically, the phase of the high-frequency signal output to the fourth port P4 is delayed by 90° relative to the high-frequency signal output to the third port P3. The third transmission line 23 and the fourth transmission line 24 have equal electrical lengths. Therefore, high-frequency signals with a 90° phase difference are supplied to the two power supply points 32A and 32B of the first radiating element. As a result, circularly polarized electromagnetic waves are radiated from the first radiating element 31.

[0042] Next, the receiving operation of this antenna module will be explained.

[0043] The circularly polarized wave received by the first radiating element 31 is converted into a high-frequency signal. The distribution and combining circuit 20 combines the high-frequency signals input to the third port P3 and the fourth port P4 via the third transmission line 23 and the fourth transmission line 24, and outputs them from the first port P1. More specifically, if the high-frequency signal input to the fourth port P4 is delayed by 90° relative to the high-frequency signal input to the third port P3, both are combined and output from the first port P1. If the first radiating element 31 receives a circularly polarized wave with a rotation direction corresponding to this phase relationship, the received signal is output from the first port P1 and input to the high-frequency circuit element 50 via the first transmission line 21.

[0044] Additionally, a portion of the high-frequency signal input to the first radiating element 31 is reflected by the first radiating element 31 and input to the third port P3 and the fourth port P4. The phase of this high-frequency signal in the third port P3 is 90° ahead of the phase in the fourth port P4. The high-frequency signal with this phase relationship is synthesized by the distribution and synthesis circuit 20 and output to the second port P2.

[0045] The second transmission line 22 is longer than any of the first transmission line 21, the third transmission line 23, and the fourth transmission line 24. For example, when viewed from above, the second transmission line 22 has a tortuous shape. No lumped constant circuit elements such as chip resistors are connected to the second transmission line 22. Furthermore, when viewed from the second port P2, the terminal of the second transmission line 22 is open. Alternatively, the terminal of the second transmission line 22 can be short-circuited to a ground conductor.

[0046] Figure 2 yes Figure 1The cross-sectional view is shown on the dashed line 2-2. A fourth transmission line 24 and a ground conductor 42 are disposed on the surface of a substrate 40 made of dielectric material. Furthermore, a ground conductor 41 is disposed in the inner layer of the substrate 40. The surface ground conductor 42 is connected to the inner layer ground conductor 41 via a plurality of conductive conductors 43.

[0047] Although Figure 2 Not shown in the cross-sectional view, but disposed on the surface of the substrate 40. Figure 1 The first transmission line 21, the second transmission line 22, the third transmission line 23, and the distribution and synthesis circuit 20 are shown. The first transmission line 21, the second transmission line 22, the third transmission line 23, and the fourth transmission line 24, together with the inner layer ground conductor 41, constitute a microstrip circuit. High-frequency circuit elements 50 are mounted on the substrate 40. Figure 1 High-frequency circuit elements 50 include, for example, high-frequency integrated circuit elements (RFICs), system-in-package (SiP) modules containing high-frequency integrated circuit elements, etc.

[0048] The fourth transmission line 24 and the grounding conductor 42 are covered by a protective film 45. The first radiating element 31 is fixed to the protective film 45 via a dielectric block 35. Viewed from above, the first radiating element 31 is contained within the grounding conductor 42. A power supply component 33 extending from the first radiating element 31 is connected to the front end of the fourth transmission line 24 via solder 34 or the like. The first radiating element 31 and the power supply component 33 are formed, for example, by stamping a sheet of metal. Alternatively, the power supply component 33 and the fourth transmission line 24 can be coupled via capacitive or inductive coupling. The first radiating element 31 and the grounding conductor 42 operate as a patch antenna.

[0049] Alternatively, the conductor pattern disposed on the surface of the substrate 40 can be used as the first radiating element 31, and the first radiating element 31 and the built-in grounding conductor 41 can form a patch antenna.

[0050] Next, the superior effects of the first embodiment will be explained.

[0051] In the first embodiment, the high-frequency signal reflected by the first radiating element 31 and transmitted in the third transmission line 23 and the fourth transmission line 24 is combined by the distribution and combining circuit 20 and output from the second port P2. The high-frequency signal output from the second port P2 is transmitted in the second transmission line 22 and reflected back to the second port P2 by the terminal of the second transmission line 22.

[0052] The high-frequency signal returning to the second port P2 is distributed to the third port P3 and the fourth port P4, and then input again to the power supply points 32A and 32B of the first radiating element. The phase relationship of the two high-frequency signals input again to power supply points 32A and 32B is opposite to the phase relationship of the two high-frequency signals supplied from the high-frequency circuit element 50 to power supply points 32A and 32B, respectively. For example, in the high-frequency signal supplied from the high-frequency circuit element 50, the phase of power supply point 32B is delayed by 90° compared to the phase of power supply point 32A, while in the high-frequency signal input again to the first radiating element, the phase of power supply point 32B is advanced by 90° compared to the phase of power supply point 32A. Therefore, the high-frequency signal input again to the first radiating element 31 reduces the roundness (axial ratio) of the circularly polarized wave radiated from the first radiating element.

[0053] In the first embodiment, since the second transmission line 22 is longer than any one of the first transmission line 21, the third transmission line 23, and the fourth transmission line 24, the high-frequency signal output from the second port P2 is significantly attenuated before it returns to the second port P2 after circling back and forth in the second transmission line 22. Therefore, the reduction in the roundness of the circularly polarized wave caused by the high-frequency signal being re-inputted to the first radiating element can be suppressed.

[0054] Furthermore, even if the second port P2 is terminated by a chip resistor or similar element having an impedance equal to the characteristic impedance of the transmission line, a sufficiently reflection-free termination cannot be achieved for high-frequency signals in the quasi-millimeter wave band and millimeter wave band above 20 GHz. In the first embodiment, the second port P2 is terminated not by a chip resistor or similar element, but by the second transmission line 22. Therefore, for high-frequency signals in the quasi-millimeter wave band and millimeter wave band, a reflection-free termination that sufficiently attenuates the high-frequency signal waves oscillating back and forth in the second transmission line 22 can also be achieved.

[0055] In order to maintain sufficient roundness of the circularly polarized wave radiated from the first radiating element 31, the length of the second transmission line 22 can be set such that the attenuation of the high-frequency signal during reciprocating motion in the second transmission line 22 is greater than 10dB.

[0056] Next, a variation of the first embodiment will be described.

[0057] In the first embodiment, a 90° mixing circuit is used as the distribution and synthesis circuit 20, but other distribution and synthesis circuits with the following functions can also be used: the high-frequency signal input to the first port P1 is distributed to the third port P3 and the fourth port P4, the high-frequency signal input again from the third port P3 and the fourth port P4 is synthesized and output from the second port P2.

[0058] In the first embodiment, the length of the second transmission line 22 is extended by making it into a tortuous shape, but it can also be formed into other shapes. For example, according to the substrate 40 ( Figure 2 The shape of the free area can be used to configure the second transmission line 22.

[0059] In the first embodiment, the second transmission line 22 is not connected to lumped constant circuit elements such as chip resistors, so that its terminals are open or short-circuited. However, surface-mounted passive components such as resistors, inductors, and capacitors can be connected to the second transmission line 22 as terminals. Since surface-mounted passive components do not function as fully reflection-free terminals even in the quasi-millimeter wave band and millimeter wave band, the high-frequency signals transmitted in the second transmission line 22 are sufficiently attenuated, thus maintaining the effect of suppressing the re-input of high-frequency signals to the first radiating element 31.

[0060] In the first embodiment, microstrip lines are used as the first transmission line 21, the second transmission line 22, the third transmission line 23, and the fourth transmission line 24, but other transmission line structures, such as strip lines, can also be used.

[0061] [Second Embodiment]

[0062] Next, refer to Figure 3 The antenna module of the second embodiment will be described below. Hereinafter, the antenna module 10 of the first embodiment (…) will be compared with… Figure 1 , Figure 2 The common structure is omitted.

[0063] Figure 3 This is a top view of the antenna module 10 according to the second embodiment. In the first embodiment, a first radiating element 31 is disposed on the surface of the substrate 40. In the second embodiment, in addition to the first radiating element 31, a plurality of second radiating elements 36 are disposed. The plurality of second radiating elements 36 are respectively connected to a high-frequency circuit element 50 via a plurality of fifth transmission lines 25 disposed on the substrate 40. The high-frequency circuit element 50 includes a second high-frequency circuit, which performs at least one of transmitting and receiving high-frequency signals for each second radiating element 36. The second transmission line 22 is longer than any one of the plurality of fifth transmission lines 25. And, similarly to the first embodiment, the second transmission line 22 is longer than any one of the first transmission line 21, the third transmission line 23, and the fourth transmission line 24.

[0064] Next, the superior effects of the second embodiment will be explained.

[0065] In the second embodiment, since the second transmission line 22 is longer than the other transmission lines provided on the substrate 40, the high-frequency signal reciprocating in the second transmission line 22 can be significantly attenuated. Therefore, since the signal level of the high-frequency signal input again to the first radiating element 31 is reduced, the reduction in the roundness of the circularly polarized wave radiated from the first radiating element 31 can be suppressed. Furthermore, in the second embodiment, since the fifth transmission line 25 is relatively shorter than the second transmission line 22, the attenuation of the high-frequency signal transmitted and received between the second radiating element 36 and the high-frequency circuit element 50 can be suppressed.

[0066] Next, a variation of the second embodiment will be described.

[0067] In the second embodiment, a first high-frequency circuit for transmitting and receiving high-frequency signals to the first radiating element 31 and a second high-frequency circuit for transmitting and receiving high-frequency signals to the second radiating element 36 are implemented using a single high-frequency circuit element 50. As a variation, different high-frequency circuit elements can also be used to implement the first and second high-frequency circuits.

[0068] [Third Embodiment]

[0069] Next, refer to Figure 4 The antenna module of the third embodiment will be described below. Hereinafter, the antenna module 10 of the first embodiment (…) will be compared with… Figure 1 , Figure 2 The common structure is omitted.

[0070] Figure 4 This is a cross-sectional view of the first transmission line 21 and the second transmission line 22 of the antenna module 10 according to the third embodiment. The first transmission line 21 and the second transmission line 22 are disposed on the surface of the substrate 40, and a grounding conductor 41 is disposed in the inner layer. The first transmission line 21 and the second transmission line 22 are covered by a protective film 45.

[0071] The surface roughness of the second transmission line 22 is greater than that of the first transmission line 21. Furthermore, the third transmission line 23 and the fourth transmission line 24 ( Figure 1 The surface roughness of the second transmission line 22 is approximately the same as that of the first transmission line 21. Parameters defining surface roughness can include, for example, arithmetic mean roughness Ra, root mean square height Rq, etc. (e.g., JIS B0601-2001, ISO4287-1997). For example, by masking the area other than where the second transmission line 22 is located, and performing plasma treatment, wet etching, sandblasting, etc., the surface of the second transmission line 22 can be made rougher than the surfaces of other transmission lines.

[0072] Next, the superior effects of the third embodiment will be explained.

[0073] Because the surface of the second transmission line 22 is rougher than the surfaces of the first transmission line 21, the third transmission line 23, and the fourth transmission line 24, the transmission loss per unit length of the second transmission line 22 is greater than that of the other transmission lines. Therefore, compared to the first embodiment, even if the second transmission line 22 is shortened, the high-frequency signal reciprocating in the second transmission line 22 can be sufficiently attenuated. Since the second transmission line 22 can be shortened, the area occupied by the second transmission line 22 on the surface of the substrate 40 can be reduced.

[0074] [Fourth Embodiment]

[0075] Next, refer to Figure 5 The antenna module of the fourth embodiment will be described below. Hereinafter, the antenna module 10 of the first embodiment (…) will be compared with… Figure 1 , Figure 2 The common structure is omitted.

[0076] Figure 5 This is a top view of the antenna module 10 according to the fourth embodiment. In the first embodiment, the substrate 40 ( Figure 1 It is formed of a uniform dielectric material. In contrast, in the fourth embodiment, the dielectric loss tangent (tanδ) of region 40A in the substrate 40 that overlaps with the second transmission line 22 when viewed from above is greater than the dielectric loss tangent of other regions 40B. Figure 5 In the diagram, a relatively darker, downward-sloping shaded line is marked in region 40A where the dielectric loss tangent is relatively large, while a relatively lighter, upward-sloping shaded line is marked in other regions 40B. Here, "dielectric loss tangent" refers to the dielectric loss tangent at the resonant frequency of the first radiating element 31. Furthermore, the determination of the dielectric loss tangent of a dielectric material can be achieved using methods such as the resonator method, the coaxial probe method, and the reflection transmission method (S-parameter method) (JIS R 1660-1:2004, etc.). When determining the dielectric loss tangent using the reflection transmission method (S-parameter method), any one of the coaxial / waveguide method or the free-space method can be applied.

[0077] For example, by using a substrate containing glass fiber as substrate 40, different glass fiber contents can result in different dielectric loss tangents for the two regions 40A and 40B. Alternatively, the dielectric materials of the two regions 40A and 40B can be different. When the dielectric constant of the substrate 40 near the second transmission line 22 differs from that near other transmission lines, it is preferable to make the characteristic impedance of the second transmission line 22 equal to that of the other transmission lines by making the width of the second transmission line 22 different from the width of the other transmission lines.

[0078] Next, the superior effects of the fourth embodiment will be explained.

[0079] Because the dielectric loss tangent of the dielectric material disposed near the second transmission line 22 is greater than that of the dielectric material in other regions, the transmission loss per unit length of the second transmission line 22 is greater than that per unit length of the first transmission line 21, the third transmission line 23, and the fourth transmission line 24. Therefore, even if the second transmission line 22 is shortened compared to the first embodiment, the high-frequency signal reciprocating in the second transmission line 22 can be sufficiently attenuated. Since the second transmission line 22 can be shortened, the area occupied by the second transmission line 22 on the surface of the substrate 40 can be reduced.

[0080] Next, a variation of the fourth embodiment will be described.

[0081] In the fourth embodiment, region 40A, which has a relatively large dielectric loss tangent when viewed from above, includes approximately the entire second transmission line 22, but it is not necessary for the entire second transmission line 22 to be contained within region 40A. For example, a portion of the second transmission line 22 may protrude from region 40A when viewed from above. That is, it is sufficient that the dielectric loss tangent of at least a portion of the region overlapping with the second transmission line 22 when viewed from above is greater than the dielectric loss tangent of other regions. In this case, the attenuation of the high-frequency signal reciprocating in the second transmission line 22 also increases.

[0082] [Fifth Embodiment]

[0083] Next, refer to Figure 6 The antenna module of the fifth embodiment will be described below. Hereinafter, the antenna module 10 of the first embodiment (…) will be compared with… Figure 1 , Figure 2 The common structure is omitted.

[0084] Figure 6 This is a top view of the antenna module 10 in the fifth embodiment. In the first embodiment ( Figure 1 In the first embodiment, the third transmission line 23 and the fourth transmission line 24 are respectively connected to different power supply points 32A and 32B of a first radiating element 31. In contrast, in the fifth embodiment, the third transmission line 23 is connected to power supply point 37A of the radiating element 31A, and the fourth transmission line 24 is connected to power supply point 37B of another radiating element 31B.

[0085] Radiation elements 31A and 31B radiate linearly polarized waves with mutually orthogonal polarization wavefronts. The high-frequency signals supplied to power supply point 37A of one radiation element 31A and power supply point 37B of the other radiation element 31B are 90° out of phase. Therefore, the linearly polarized waves radiated from the two radiation elements 31A and 31B are combined into a circularly polarized wave.

[0086] Next, the superior effects of the fifth embodiment will be explained.

[0087] In the fifth embodiment, since the second transmission line 22 is longer than the other transmission lines, it can also achieve the same excellent effect as the first embodiment, which is able to suppress the reduction of the roundness of the circularly polarized wave.

[0088] [Sixth Embodiment]

[0089] Next, refer to Figure 7 The antenna module of the sixth embodiment will be described below. Hereinafter, the antenna module 10 of the first embodiment (…) will be compared with… Figure 1 , Figure 2 The common structure is omitted.

[0090] Figure 7 This is a diagram showing the positional relationship of the transmission lines, radiating elements, etc., constituting the antenna module 10 of the sixth embodiment in the thickness direction. Figure 7 The diagram is based on the electrical connections of the conductor portion and does not represent the structure of a specific cross-section of the antenna module 10.

[0091] In the first embodiment, the first radiating element 31 is fixed to the substrate 40 via a dielectric block 35. In contrast, in the sixth embodiment, the first radiating element 31 is composed of a conductive film disposed on one surface of the substrate 40 (hereinafter referred to as the upper surface). Furthermore, in the first embodiment, the first transmission line 21, the second transmission line 22, the third transmission line 23, the fourth transmission line 24, and the distribution and synthesis circuit 20 are disposed on the surface of the substrate 40. In contrast, in the sixth embodiment, these transmission lines and the distribution and synthesis circuit 20 are disposed in the inner layer of the substrate 40. Figure 7 The diagram shows the first transmission line 21, the second transmission line 22, the third transmission line 23, and the distribution and synthesis circuit 20.

[0092] The substrate 40 includes two conductor layers and three ground conductor layers 46. The third transmission line 23 and the distribution and synthesis circuit 20 are disposed on the upper conductor layer, and the first transmission line 21 and the second transmission line 22 are disposed on the lower conductor layer. Each conductor layer is held by the ground conductors 46 in the thickness direction.

[0093] The first radiating element 31 is connected to the third transmission line 23 via a conductive conductor 47A that passes through the uppermost grounding conductor 46. The third transmission line 23 is connected to the third port P3 of the distribution and combining circuit 20. The first transmission line 21 is connected to the first port P1 of the distribution and combining circuit 20 via a conductive conductor 47B that passes through the grounding conductor 46. The second transmission line 22 is connected to the second port P2 of the distribution and combining circuit 20 via a conductive conductor 47C that passes through the grounding conductor 46.

[0094] Multiple grounding conductors 48 are configured to surround the second transmission line 22 when viewed from above. The multiple grounding conductors 48 are connected to two grounding conductors 46 respectively disposed above and below the second transmission line 22.

[0095] Next, the superior effects of the sixth embodiment will be explained.

[0096] In the sixth embodiment, since the first radiating element 31 does not pass through the dielectric block 35 ( Figure 2 The second transmission line 22, being formed on the upper surface of the substrate 40, reduces the number of components. Furthermore, the relatively long second transmission line 22 is prone to becoming a noise source. In the sixth embodiment, the second transmission line 22 is shielded by grounding conductors 46 above and below it, and by a plurality of grounding conductors 48 surrounding it when viewed from above. Therefore, the impact of noise generated from the second transmission line 22 can be reduced. For example, it can suppress disturbances in the radiation pattern of the first radiating element 31, overlap of noise with the power supply, and oscillations caused by mutual interference.

[0097] Furthermore, in the sixth embodiment, a third transmission line 23 connected to the first radiating element 31 is disposed in the inner layer, and a grounding conductor 46 is disposed between the first radiating element 31 and the transmission line in the inner layer. Therefore, electromagnetic interference between the first radiating element 31 and the transmission line in the inner layer can be suppressed.

[0098] Next, a variation of the sixth embodiment will be described.

[0099] In the sixth embodiment, grounding conductors 46 are arranged above and below the second transmission line 22, and are surrounded by multiple grounding conductors 48 when viewed from above. That is, the second transmission line 22 is surrounded three-dimensionally from all directions, but it is not necessary for it to be surrounded from all directions. It is also possible to configure the grounding conductors 46 or grounding conductors 48 between the element that is to be avoided from interfering with noise sources and the second transmission line 22 to reduce the coupling between the two. Examples of elements that are to be avoided from interfering with noise sources include integrated circuit components, power lines, high-frequency transmission lines, radiating elements, and power supply lines for radiating elements.

[0100] [Seventh Embodiment]

[0101] Next, refer to Figure 8 The antenna module of the seventh embodiment will be described below. Hereinafter, the antenna module 10 of the sixth embodiment (…) will be compared with… Figure 7 The common structure is omitted.

[0102] Figure 8 This is a diagram showing the positional relationship of the transmission lines, radiating elements, etc., constituting the antenna module 10 of the seventh embodiment in the thickness direction. Figure 8 The diagram is based on the electrical connections of the conductor portion and does not represent the structure of a specific cross-section of the antenna module 10.

[0103] In the sixth embodiment ( Figure 7 In the first embodiment, the entire area of ​​the second transmission line 22 is disposed on the lower conductor layer, and one end of the second transmission line 22 is connected to the second port P2 of the distribution and synthesis circuit 20 via a conductive conductor 47C. In contrast, in the seventh embodiment, the second transmission line 22 is distributed across both the upper and lower conductor layers. The portion of the second transmission line 22 disposed on the upper conductor layer and the portion disposed on the lower conductor layer are interconnected via a conductive conductor 47D. The end of the portion of the second transmission line 22 disposed on the upper conductor layer is connected to the second port P2 of the distribution and synthesis circuit 20.

[0104] Next, the superior effects of the seventh embodiment will be explained.

[0105] In the seventh embodiment, portions of the second transmission line 22 disposed on different conductor layers can be arranged to overlap each other when viewed from above. Therefore, the area occupied by the second transmission line 22 can be reduced. Furthermore, the portion of the second transmission line 22 disposed on the lower conductor layer is similar to the second transmission line 22 in the sixth embodiment (…). Figure 7 Similarly, being surrounded by grounding conductor 46 and grounding conduction conductor 48, the impact of noise generated from the portion of the conductor layer disposed on the lower side of the second transmission line 22 can be reduced.

[0106] Next, a variation of the seventh embodiment will be described.

[0107] In the seventh embodiment, the second transmission line 22 is distributed across two conductor layers, but it can also be distributed across three or more conductor layers.

[0108] [Eighth Embodiment]

[0109] Next, refer to Figure 9 The antenna module of the eighth embodiment will be described below. Hereinafter, the antenna module 10 of the seventh embodiment (…) will be compared with… Figure 8 The common structure is omitted.

[0110] Figure 9 This is a diagram showing the positional relationship of the transmission lines, radiating elements, etc., constituting the antenna module 10 of the eighth embodiment in the thickness direction. Figure 9 The diagram is based on the electrical connections of the conductor portion and does not represent the structure of a specific cross-section of the antenna module 10.

[0111] In the seventh embodiment ( Figure 8 In the first embodiment, a grounding conductor 46 is disposed between the distribution and synthesis circuit 20, the second transmission line 22, the third transmission line 23, etc., disposed on the upper conductor layer and the first radiating element 31 on the upper surface. A grounding conductor 46 is also disposed below the first transmission line 21, the second transmission line 22, etc., disposed on the lower conductor layer. In contrast, in the eighth embodiment, these grounding conductors are not disposed. A grounding conductor 46 is disposed between the distribution and synthesis circuit 20, the second transmission line 22, the third transmission line 23, etc., disposed on the upper conductor layer and the first transmission line 21, the second transmission line 22, etc., disposed on the lower conductor layer.

[0112] exist Figure 8 In the diagram, radiating elements other than the first radiating element 31 and transmission lines are not shown on the upper surface of the substrate 40, nor are high-frequency circuit elements 50 mounted on the lower surface of the substrate 40. Figure 1 In contrast, in Figure 9 The diagram illustrates a conductor pattern 51, such as a radiating element or transmission line, disposed on the upper surface of the substrate 40, and a high-frequency circuit element 50 mounted on the lower surface of the substrate 40.

[0113] The thickness-direction intervals from the second transmission line 22 disposed on the upper conductor layer to the ground conductor 46 and to the conductor pattern 51 disposed on the upper surface of the substrate 40 are respectively denoted as Ga and Gb. The thickness-direction intervals from the second transmission line 22 disposed on the lower conductor layer to the ground conductor 46 and to the lower surface of the substrate 40 are respectively denoted as Gc and Gd. In the eighth embodiment, the relationships Ga < Gb and Gc < Gd hold.

[0114] Next, the superior effects of the eighth embodiment will be explained.

[0115] In the eighth embodiment, since the relationships Ga < Gb and Gc < Gd hold, power is concentrated in the space between the lower surface of the second transmission line 22 disposed on the upper conductor layer and the upper surface of the ground conductor 46, and in the space between the upper surface of the second transmission line 22 disposed on the lower conductor layer and the lower surface of the ground conductor 46. Therefore, interference between the second transmission line 22 and the conductor pattern 51, which can be a noise source, and between the second transmission line 22 and the high-frequency circuit element 50 are suppressed. As a result, the conductor pattern 51 and the high-frequency circuit element 50 are less susceptible to noise from the second transmission line 22.

[0116] [Ninth Embodiment]

[0117] Next, refer to Figure 10 The antenna module of the ninth embodiment will be described below. Hereinafter, the antenna module 10 of the first embodiment (…) will be compared with… Figure 1 , Figure 2 The common structure is omitted.

[0118] Figure 10 This is a diagram showing the positional relationship of the transmission lines, radiating elements, etc., constituting the antenna module 10 of the ninth embodiment in the thickness direction. Figure 10 The diagram is based on the electrical connections of the conductor portion and does not represent the structure of a specific cross-section of the antenna module 10.

[0119] In the first embodiment ( Figure 2 In the first embodiment, transmission lines 21, 22, 23, 24, and a distribution and synthesis circuit 20 are disposed on the upper surface of the substrate 40. In contrast, in the ninth embodiment, these transmission lines and the distribution and synthesis circuit 20 are disposed in the inner layer of the substrate 40. The structure of the transmission lines and the distribution and synthesis circuit 20 in the inner layer of the substrate 40 is, for example, similar to that in the sixth embodiment. Figure 7 These structures are the same for the antenna modules of ).

[0120] External connection terminals 38 and grounding conductors 46 are disposed on the upper surface of substrate 40. External connection terminals 38 are connected to the third transmission line 23 of the inner layer via a conductive conductor 47E. A dielectric block 35 holding the first radiating element 31 is disposed on the grounding conductor 46 on the upper surface of substrate 40. The power supply point 32A of the first radiating element 31 is connected to the external connection terminals 38. Although in Figure 10 Not shown in the diagram, but another power supply point 32B of the first radiating element 31 ( Figure 1 It is also connected to the fourth transmission line 24 via other external connection terminals and conductive conductors.

[0121] Next, the superior effects of the ninth embodiment will be explained.

[0122] In the ninth embodiment, a grounding conductor 46 is disposed between the first radiating element 31 and the transmission lines of the inner layer of the substrate 40. Therefore, the coupling between the first radiating element 31 and the transmission lines of the inner layer of the substrate 40 is reduced, and the reduction in the radiation characteristics of the first radiating element 31 is suppressed.

[0123] [Tenth Embodiment]

[0124] Next, refer to Figure 11A as well as Figure 11B The antenna module of the tenth embodiment will be described below. Hereinafter, the antenna module 10 of the ninth embodiment (…) will be compared with… Figure 10 The common structure is omitted.

[0125] Figure 11A as well as Figure 11B This is a diagram showing the positional relationship of the transmission lines, radiating elements, etc., constituting the antenna module 10 of the tenth embodiment in the thickness direction, as well as the external first radiating element 31. Figure 11A as well as Figure 11B The diagram is based on the electrical connections of the conductor portion and does not represent the structure of a specific cross-section of the antenna module 10.

[0126] In the ninth embodiment ( Figure 10 In the first embodiment, the antenna module 10 includes a first radiating element 31. In contrast, the antenna module 10 of the tenth embodiment does not have a first radiating element 31, but has an external connection terminal 38 for connecting to the externally disposed first radiating element 31.

[0127] exist Figure 11A In the example shown, a first radiating element 31 is disposed on the inner surface of the housing 60 housing the antenna module 10. Figure 11B In the example shown, a first radiating element 31 is embedded in the housing 60. The first radiating element 31 and the external connection terminal 38 of the antenna module 10 are connected via a conductor post 61. The conductor post 61 can be, for example, a spring pin.

[0128] Next, the superior effects of the tenth embodiment will be explained.

[0129] In the tenth embodiment, the first radiating element 31 can be configured at a desired location outside the antenna module 10. Therefore, it is possible to obtain an excellent effect of increasing the degree of freedom in configuring the position of the first radiating element 31.

[0130] The above embodiments are illustrative, and of course, different substitutions or combinations of the structures shown in the embodiments are possible. The same effects resulting from the same structures in multiple embodiments are not mentioned sequentially in each embodiment. Furthermore, the present invention is not limited to the above embodiments. For example, various changes, improvements, and combinations will be apparent to those skilled in the art.

[0131] Explanation of reference numerals in the attached figures

[0132] 10…Antenna module; 20…Distribution and combining circuit; 21…First transmission line; 22…Second transmission line; 23…Third transmission line; 24…Fourth transmission line; 25…Fifth transmission line; 31…First radiating element; 31A, 31B…Radiating elements; 32A, 32B…Power supply points; 33…Power supply components; 34…Solder; 35…Dielectric block; 36…Second radiating element; 37A, 37B…Power supply points; 38…Terminals for external connection; 40…Substrate; 40A…Dielectric Areas with large loss tangent; 40B…areas with small dielectric loss tangent; 41, 42…grounding conductors; 43…conducting conductors; 45…protective film; 46…grounding conductors; 47A, 47B, 47C, 47D, 47E…conducting conductors; 48…grounding and conducting conductors; 50…high-frequency circuit components; 51…conductor patterns for radiating components, transmission lines, etc.; 60…shell; 61…conductor post; P1…first port; P2…second port; P3…third port; P4…fourth port.

Claims

1. An antenna module, comprising: a distribution circuit having a first port, a second port, a third port, and a fourth port; a first transmission line, a second transmission line, a third transmission line, and a fourth transmission line connected to the first port, the second port, the third port, and the fourth port, respectively; a first high-frequency circuit connected to the first port via the first transmission line, and performing at least one of transmission and reception of a high-frequency signal to and from the first port via the first transmission line; and at least one first radiating element connected to the third port and the fourth port via the third transmission line and the fourth transmission line, respectively, wherein the distribution circuit distributes and outputs a high-frequency signal input to the first port to the third port and the fourth port, combines a high-frequency signal reflected by the first radiating element and input to the third port and the fourth port, and outputs the combined high-frequency signal to the second port, the second transmission line is longer than any one of the first transmission line, the third transmission line, and the fourth transmission line, and a surface roughness of the second transmission line is greater than a surface roughness of the first transmission line, the third transmission line, and the fourth transmission line.

2. The antenna module according to claim 1, wherein the distribution circuit, the first transmission line, the second transmission line, the third transmission line, and the fourth transmission line are provided on a common substrate, further comprising: at least one second radiating element provided on the substrate; a second high-frequency circuit performing at least one of transmission and reception of a high-frequency signal to and from each of the second radiating elements; and a fifth transmission line provided on the substrate and connected between the second high-frequency circuit and each of the second radiating elements, wherein the second transmission line is longer than the fifth transmission line.

3. The antenna module according to claim 1 or 2, wherein a dielectric loss tangent of at least a portion of a dielectric material provided in a region overlapping the second transmission line in plan view is greater than a dielectric loss tangent of a dielectric material provided in a region overlapping any one of the first transmission line, the third transmission line, and the fourth transmission line.

4. The antenna module according to any one of claims 1 to 3, wherein the first high-frequency circuit supplies a high-frequency signal of 20 GHz or more to the first radiating element.

5. The antenna module according to any one of claims 1 to 4, wherein a chip resistor element is not connected to the first transmission line.

6. An antenna module, comprising: a distribution circuit having a first port, a second port, a third port, and a fourth port; a first transmission line, a second transmission line, a third transmission line, and a fourth transmission line connected to the first port, the second port, the third port, and the fourth port, respectively; a first high-frequency circuit connected to the first port via the first transmission line, and performing at least one of transmission and reception of a high-frequency signal to and from the first port via the first transmission line; and at least one first radiating element connected to the third port and the fourth port via the third transmission line and the fourth transmission line, respectively, wherein the distribution circuit distributes and outputs a high-frequency signal input to the first port to the third port and the fourth port, combines a high-frequency signal reflected by the first radiating element and input to the third port and the fourth port, and outputs the combined high-frequency signal to the second port, the second transmission line is longer than any one of the first transmission line, the third transmission line, and the fourth transmission line, and a surface roughness of the second transmission line is greater than a surface roughness of the first transmission line, the third transmission line, and the fourth transmission line. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ two external connection terminals connected to the third port and the fourth port, respectively, The above-mentioned distribution circuit distributes and outputs the high frequency signal inputted to the above-mentioned first port to the above-mentioned third port and the above-mentioned fourth port, and synthesizes and outputs the high frequency signal reflected by the radiating element and inputted to the above-mentioned third port and the above-mentioned fourth port to the above-mentioned second port, wherein, the radiating element is connected to the external connection terminals, the second transmission line is longer than any of the first, third, and fourth transmission lines, the second transmission line has a surface roughness greater than that of the first, third, and fourth transmission lines.

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