antenna

Abstract

To enable compact configuration and support for multiple frequency bands.SOLUTION: An antenna 3 includes; an antenna unit 30 having first, second, and third antenna elements 31, 32, and 33 on an antenna surface 3A; ground units 40; and slit units 50 formed between the antenna unit and the ground unit. In the antenna 3, a back-surface ground portion 60 is formed on a second conductive layer 22 of an antenna back surface 3B. Further, in the antenna 3, a length of each side of the antenna unit 30, the ground unit 40, and the ground unit 60 is made to be different from a length that resonates with each frequency of a 800 MHz band. Therefore, the antenna 3 resonates with no supplied electric signal in these frequency bands, and can function well as a traveling-wave antenna. Thus, the antenna 3 can obtain good characteristics in a plurality of frequency bands while being configured in a relatively small thin plate shape.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to an antenna, and is suitable for application to a small antenna compatible with multiple frequency bands, for example. [Background technology]

[0002] Conventionally, information and communication devices that communicate information wirelessly by incorporating wireless communication functions into various electronic devices such as smartphones and tablet terminals have become widespread. Such information and communication devices must be equipped with an antenna for wireless communication.

[0003] These information and communication devices are also equipped with wireless communication functions that comply with wireless LAN (Local Area Network) standards such as IEEE (Institute of Electrical and Electronics Engineers) 802.11a / b / g / n / ac / ax / be, or mobile communication standards known as 5G (5th Generation, or 5th Generation Mobile Communication System). These standards use multiple frequency bands based on factors such as radio wave characteristics and communication capacity according to the frequency, as well as interference with frequencies used for other purposes. For this reason, information and communication devices require multiple antennas to support each frequency.

[0004] On the other hand, in many cases, miniaturization is required for information and communication devices from the viewpoint of improving portability, adaptability to various installation locations, etc. Therefore, an antenna that is configured to be compact while supporting multiple frequency bands has been proposed, for example, by combining a portion that functions as a standing wave antenna and a portion that functions as a traveling wave antenna (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] U.S. Patent No. 9,257,747 Summary of the Invention [Problem to be solved by the invention]

[0006] However, there are cases where the above-mentioned information and communication devices are required to be further miniaturized while being compatible with multiple frequency bands.

[0007] The present invention has been made in consideration of the above points, and aims to propose an antenna that can be constructed compactly and is compatible with a plurality of frequency bands. [Means for solving the problem]

[0008] In order to solve this problem, the antenna of the present invention has an antenna section formed on the surface of a substrate and having three antenna elements, a ground section formed around the antenna section on the surface of the substrate and facing a part of the antenna section, and a slit section formed between the antenna section and the ground section on the surface of the substrate, so that the antenna section and the ground section do not resonate at a plurality of predetermined frequencies.

[0009] In the present invention, the lengths of the sides of each part constituting the antenna section and the lengths of the sides of each part constituting the ground section are made different from the lengths that resonate at a plurality of predetermined frequencies, thereby enabling the present invention to function as a traveling wave antenna at each of the plurality of predetermined frequencies. [Effects of the Invention]

[0010] According to the present invention, it is possible to realize an antenna that can be configured compactly and is compatible with multiple frequency bands. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a schematic diagram illustrating an overall configuration of a wireless communication device. [Figure 2] FIG. 1 is a six-view diagram showing the configuration of the antenna. [Figure 3] FIG. 2 is a schematic cross-sectional view showing the configuration of an antenna. [Figure 4] FIG. 2 is a schematic diagram showing the configuration of the antenna surface. [Figure 5] FIG. 2 is a schematic diagram illustrating the configuration of the rear surface of the antenna. [Figure 6] 10A and 10B are schematic diagrams showing simulation results of current density distribution. [Figure 7] FIG. 10 is a schematic diagram showing the measurement results of VSWR. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, modes for carrying out the invention (hereinafter referred to as embodiments) will be described with reference to the drawings.

[0013] [1. Configuration of wireless communication device] 1, a wireless communication device 1 according to this embodiment has a configuration in which a main board 2 and an antenna 3 are connected by a connection cable 4. This wireless communication device 1 is, for example, a communication device called a Wi-Fi (registered trademark) router, and has a wireless communication function conforming to the 5G standard, and also conforms to wireless LAN standards such as IEEE802.11a / b / g / n / ac / ax / be, and is capable of transmitting and receiving various information to and from various electronic devices that are wirelessly connected.

[0014] The main board 2 is a circuit board and is provided with an information processing circuit 11 that performs various types of information processing, a high-frequency circuit 12 that performs processing related to high-frequency signals, etc. The high-frequency circuit 12 is connected to the information processing circuit 11 and the connection cable 4, and performs modulation processing, demodulation processing, etc. Incidentally, a coaxial connector 13 that complies with standards such as SMA (Sub Miniature Type A) is provided at the connection point of the high-frequency circuit 12 with the connection cable 4.

[0015] For example, when information is supplied from the information processing circuit 11, the high-frequency circuit 12 modulates the information to generate a high-frequency signal, which is then supplied to the connection cable 4. Furthermore, when a high-frequency signal is supplied from the connection cable 4, the high-frequency circuit 12 demodulates the high-frequency signal to extract information, which is then supplied to the information processing circuit 11.

[0016] The connection cable 4 is, for example, a coaxial cable, one end of which is connected to the high-frequency circuit 12 on the main board 2, and the other end of which is connected to the antenna 3. Coaxial connectors corresponding to the respective connection destinations are provided on both ends of the connection cable 4.

[0017] [2. Antenna configuration] Next, we will explain the configuration of the antenna 3. The antenna 3 has the same function as a general antenna, and when power of a predetermined frequency is supplied from the main board 2 via the connection cable 4, it emits this into the air as high-frequency radio waves. The antenna 3 also receives the radio waves of the predetermined frequency being emitted into the air, converts them into an electrical signal, and supplies it to the main board 2 via the connection cable 4.

[0018] The antenna 3 is configured as a rectangular plate overall, as shown in six-sided views in Fig. 2. In Fig. 2, (A) is a plan view (top view), (B) is a rear view, (C) is a front view, (D) is a bottom view (lower view), (E) is a left side view, and (F) is a right side view.

[0019] The antenna 3 is configured as a glass epoxy board (i.e., a printed circuit board) that complies with, for example, the FR-4 standard of the NEMA (National Electrical Manufacturers Association) / ANSI (American National Standards Institute). That is, the antenna 3 has a structure in which multiple layers with different electrical characteristics are stacked in the thickness direction.

[0020] A rectangular cutout 3C is formed slightly to the right of the center in the left-right direction at the front end of the antenna 3. This cutout 3C is formed to fit the internal shape of the housing (not shown) of the wireless communication device 1 (FIG. 1).

[0021] As shown in the schematic cross-sectional view of Figure 3, this antenna 3 is composed of a central base material layer 20, a first conductive layer 21 on the upper surface (hereinafter referred to as the antenna surface 3A or the substrate surface), and a second conductive layer 22 on the opposite lower surface (hereinafter referred to as the antenna back surface 3B or the substrate back surface). The base material layer 20 is made of so-called glass epoxy resin, and is formed into a plate shape by impregnating glass fibers with the epoxy resin and thermally curing it. The base material layer 20 has electrical properties that are non-conductive or insulating.

[0022] The first conductive layer 21 and the second conductive layer 22 are provided on the upper and lower sides, respectively, of the base layer 20, and are formed as relatively thin layers made of a conductive material such as metal (e.g., copper). A connector 25 for connecting to the connection cable 4 (FIG. 1) is provided on the upper side of the antenna 3, i.e., at a predetermined location on the first conductive layer 21. Furthermore, vias 28 that penetrate the base layer 20 are appropriately provided in the antenna 3, and electrically connect a part of the first conductive layer 21 and a part of the second conductive layer 22 (this will be described in detail later).

[0023] As shown in Figures 4 and 5, the first conductive layer 21 and the second conductive layer 22 are partially removed from the antenna front surface 3A and the antenna back surface 3B, respectively, to form a predetermined circuit pattern. Incidentally, Figure 4 shows the antenna front surface 3A as viewed from above. Figure 5 shows the antenna back surface 3B as viewed from below, with the left and right mirrored, corresponding to a see-through view of the antenna back surface 3B from above. Furthermore, in Figure 4, the portions where the first conductive layer 21 is present are shaded, and the portions where the first conductive layer 21 is not present and the base layer 20 is exposed are white (plain). Similarly, in Figure 5, the portions where the second conductive layer 22 is present are shaded.

[0024] The antenna 3 has a long side length LX3 along the left-right direction of, for example, 80 to 120 mm, and a short side length LY3 along the front-to-rear direction of, for example, 30 to 50 mm, and is configured to be installed inside the housing of the wireless communication device 1. Hereinafter, the left-to-right direction, which is the longitudinal direction of the antenna 3, will also be referred to as the X direction, and the front-to-rear direction, which is the short side direction of the antenna 3, will also be referred to as the Y direction.

[0025] The antenna surface 3A (FIG. 4) is broadly divided into an antenna portion 30, a ground portion 40, and a slit portion 50. Of these, the antenna portion 30 and the ground portion 40 are portions formed by the first conductive layer 21. On the other hand, the slit portion 50 is a portion where the non-conductive base layer 20 is exposed by locally removing the first conductive layer 21, and has insulating properties.

[0026] The antenna unit 30 is, overall, slightly smaller than the external shape of the antenna 3 and is configured in a rectangular shape with the X direction (left-right direction) as the longitudinal direction and the Y direction (front-rear direction) as the transverse direction. The antenna unit 30 is disposed near the center of the antenna surface 3A in the X direction and in contact with the rear end in the Y direction. That is, the antenna unit 30 is disposed so that its rear long side overlaps the rear end of the antenna 3, its front long side is slightly spaced from the front end of the antenna 3, and each of its left and right short sides is slightly spaced from the respective left and right ends of the antenna 3.

[0027] The antenna section 30 has a first antenna element 31, a second antenna element 32, a third antenna element 33, an antenna base 34, a power feed connection section 35, and a power feed connection terminal 36. The slit section 50 has a front slit 51, a center slit 52, a rear slit 53, a left front slit 54, a left center slit 55, a left rear slit 56, and a right slit 57.

[0028] The first antenna element 31 is formed in a rectangular shape with a length LX31 in the X direction longer than a length LY31 in the Y direction, and its right end is connected to the antenna base 34. The second antenna element 32 is located behind the first antenna element 31, with the middle slit 52 sandwiched between them, is formed in a rectangular shape with a length LX32 in the X direction longer than a length LY32 in the Y direction, and its right end is connected to the antenna base 34. The third antenna element 33 is located behind the second antenna element 32, with the rear slit 53 sandwiched between them, is formed in a rectangular shape with a length LX33 in the X direction longer than a length LY33 in the Y direction, and its right end is connected to the antenna base 34.

[0029] In addition, in the antenna unit 30, with respect to the length along the X direction, the length LX31 is greater (longer) than the lengths LX32 and LX33, and the lengths LX32 and LX33 are equal to each other. In addition, in the antenna unit 30, with respect to the length along the Y direction, the lengths LY31, LY32, and LY33 are equal to each other.

[0030] In other words, in the antenna section 30, the first antenna element 31, the second antenna element 32, and the third antenna element 33 are formed in the shape of parallel rectangles. In addition, in the antenna section 30, the first antenna element 31, the second antenna element 32, and the third antenna element 33 have the same length (width) in the Y direction, and the distance between the first antenna element 31 and the second antenna element 32 and the distance between the second antenna element 32 and the third antenna element 33 are also the same.

[0031] The antenna base 34 is located to the right of the first antenna element 31, the middle slit 52, the second antenna element 32, the rear slit 53, and the third antenna element 33, and is formed in a rectangular shape with a length LX34 in the X direction that is shorter than a length LY34 in the Y direction. A power supply connection part 35 is provided at the front end of the right side of the antenna base 34, extending rightward.

[0032] A power supply connection terminal 36 is provided at the right end of the power supply connection part 35. The power supply connection terminal 36, which serves as a power supply point, is electrically connected to the inner conductor portion of the connector 25 (FIG. 3), i.e., the portion that is connected to the inner conductor (so-called core wire) of the connection cable 4 (FIG. 1).

[0033] The ground portion 40 is generally rectangular in shape, with its outer shape roughly matching that of the antenna surface 3A, but the upper edge of the ground portion 40 has a large rectangular recessed shape extending downward in the vicinity of the center, approximately 2 / 3 of the area, and the above-mentioned antenna portion 30 is disposed inside the recessed shape.

[0034] In other words, the ground section 40 occupies the remaining part of the antenna surface 3A excluding the antenna section 30 and its vicinity. From another perspective, the ground section 40 is provided on the antenna surface 3A over a wide range from the left side of the antenna section 30 through the front side to the right side, surrounding the periphery of the antenna section 30 with the slit section 50 being a certain distance from the antenna section 30. In other words, the ground section 40 faces the front, left, and right sides of the antenna section 30 with the slit section 50 between them, but does not face the rear side of the antenna section 30.

[0035] The ground section 40 includes a front ground 41, a left front ground 42, a left rear ground 43, a right ground 44, and the like.

[0036] The front ground 41 is located in front of the first antenna element 31, with a front slit 51 sandwiched between it and the first antenna element 31, and is formed into a rectangular shape that is slightly longer in the left-right direction than the first antenna element 31 as a whole. That is, the front ground 41 faces the first antenna element 31. The left end of the front ground 41 is connected to the right front end of the left front ground 42, and the right end of the front ground 41 is connected to the left front end of the right ground 44. Furthermore, the length LY51 of the front slit 51 in the Y direction is shorter than the length LX31 of the first antenna element 31 along the Y direction and the length LY51 of the front ground 41 along the Y direction.

[0037] The left front ground 42 is formed in a rectangular shape with its overall length in the front-to-rear direction longer than its length in the left-to-right direction, and is located to the left of the front ground 41, the front slit 51, the first antenna element 31, and the center slit 52. In addition, a left front slit 54 is formed between the left front ground 42 and the first antenna element 31.

[0038] The rear end of the left front ground 42 is connected to the front left end of the left rear ground 43. The left rear ground 43 is formed in a rectangular shape with a length in the left-right direction longer than the length in the front-rear direction as a whole, and is located to the left of the second antenna element 32, rear slit 53, and third antenna element 33, with a left rear slit 56 interposed between it and the first antenna element 31 in approximately the right half of the front end of the left rear ground 43.

[0039] The right ground 44 has a length LY3 in the front-to-rear direction (i.e., Y direction) that is equal to the overall length of the antenna 3, and a length LX44 in the left-to-right direction that is shorter than this length LY3. A notch is formed in the lower part of the left side of the right ground 44 so as to avoid and surround the power supply connection part 35 and the power supply connection terminal 36, and a ground connection terminal 45 is provided on the left side of this notch. The ground connection terminal 45 is electrically connected to the outer conductor part of the connector 25 (FIG. 3), i.e., the part that is connected to the outer conductor (so-called shield) of the connection cable 4.

[0040] On the antenna back surface 3B (FIG. 5), a part of the second conductive layer 22 (FIG. 3) is removed to form a back surface ground section 60. The back surface ground section 60 is provided in an area that corresponds to the projection onto the antenna back surface 3B of the ground section 40 on the antenna front surface 3A, excluding the center to the right side of the left rear ground 43, and is electrically connected to the ground section 40 by vias 28 indicated by black dots in the figure.

[0041] The antenna 3 is designed to be compatible with radio waves in five frequency bands: 800 MHz band (815-894 MHz), 900 MHz band (880-960 MHz), 1.5 GHz band (1447-1510 MHz), 1.7 GHz band (1749-1980 MHz), and 2 GHz band (1920-2170 MHz). In addition, the antenna 3 is designed to be fully compatible with radio waves in the 2.6 GHz band.

[0042] On the antenna front surface 3A (FIG. 3(A)), the lengths of each side of the antenna section 30 and the ground section 40 along the X direction (LX3, LX31, LX43, etc.) and along the Y direction (LY3, LY31, LY34, etc.) are different from the lengths that resonate with the corresponding radio waves (i.e., lengths based on the wavelength λ, such as λ / 2 and λ / 4). Similarly, on the antenna back surface 3B, the lengths of each side of the back surface ground section 60 along the X and Y directions are different from the lengths that resonate with the corresponding radio waves (i.e., lengths based on the wavelength λ, such as λ / 2 and λ / 4). Therefore, the antenna 3 does not resonate in the corresponding frequency bands and does not operate as a standing wave antenna.

[0043] [3. Antenna characteristics] Next, we will explain the characteristics of antenna 3. Figures 6(A), (B), (C), (D), (E), and (F) show simulation results of current density distribution when electrical signals in the 800 MHz band, 900 MHz band, 1.5 GHz band, 1.7 GHz band, 2 GHz band, and 2.6 GHz band are supplied to antenna 3, respectively.

[0044] In Figure 6, multiple dots are arranged in a grid pattern overlaid on a line representing the general shape of the antenna surface 3A. The size of each dot represents the level of current density. That is, a dot with a relatively large diameter represents a relatively high current density at that location. A dot with a relatively small diameter represents a relatively low current density at that location.

[0045] For example, in Fig. 6(A), the current density is high near the point where the first antenna element 31 and the antenna base 34 are connected, but the current density gradually decreases with increasing distance from this point. In other words, in Fig. 6(A), there is no side where the current density is uniformly high among the sides constituting the antenna section 30 and the ground section 40, and some sides have a mixture of high and low current density parts. This indicates that the antenna 3 does not resonate with electrical signals in the frequency band (810 MHz band).

[0046] 6(B) to 6(F), although there are locally high current density portions, there are no sides where the current density is uniformly high on the sides constituting the antenna portion 30 and the ground portion 40. This indicates that, as in the case of the 810 MHz band, the antenna 3 does not resonate with the electrical signal in each frequency band.

[0047] Next, the VSWR (Voltage Standing Wave Ratio) of the antenna 3 was measured using a predetermined measuring device, and the results are shown in Figures 7(A) and (B). Figure 7(A) is a waveform diagram showing the measurement results, with the horizontal axis representing frequency and the vertical axis representing VSWR. Also, in Figure 7(A), triangles and dashed lines along the vertical direction are added to several representative frequencies expected to be used with the antenna 3. Figure 7(B) is a tabular summary of the VSWR values ​​at these representative frequencies. In Figures 7(A) and (B), the smaller the VSWR value, the better the performance of the antenna.

[0048] As shown in Figures 7(A) and (B), the VSWR value is 4.26 at a frequency of 814 MHz, but drops to about 3 at a higher frequency of around 840 MHz. Also shown in Figures 7(A) and (B), the VSWR value is 1.57 at a frequency of 960 MHz, 1.60 at a frequency of 1427 MHz, and 1.42 at a frequency of 1510 MHz.

[0049] Furthermore, as shown in Figures 7(A) and (B), the VSWR value is 1.77 at a frequency of 1920 [MHz], 1.73 at a frequency of 2170 [MHz], and 3.40 at a frequency of 2690 [MHz].

[0050] As described above, the VSWR value of Antenna 3 is generally 2 or less in the 900 MHz, 1.5 GHz, 1.7 GHz, and 2 GHz bands, and it was found that the performance as an antenna is good in these frequency bands. Furthermore, the VSWR value of Antenna 3 is also generally around 3 in part of the 800 MHz band and the 2.6 GHz band, and it was found that the antenna can function satisfactorily in these frequency bands.

[0051] [4. Effects, etc.] In the above configuration, the antenna 3 of the wireless communication device 1 according to this embodiment has a portion of the first conductive layer 21 on the antenna front surface 3A removed to form the antenna section 30 having the first antenna element 31, the second antenna element 32, and the third antenna element 33, and the ground section 40, with slits 50 appropriately formed between them (FIG. 4). Also, the antenna 3 has a portion of the second conductive layer 22 on the antenna back surface 3B removed to form the back surface ground section 60 (FIG. 5).

[0052] Furthermore, in the antenna 3, the lengths of the sides along the X and Y directions of the antenna part 30, the ground part 40, and the back surface ground part 60 (FIGS. 4 and 5) are made different from the lengths that resonate at predetermined frequencies, so that the antenna 3 does not function as a standing wave antenna for these frequencies.

[0053] As a result, the antenna 3 does not resonate with the supplied electrical signals in each frequency band, such as the 800 MHz band, and can function well as a traveling wave antenna. This is also reflected in the fact that in the simulation of the current density distribution for the antenna 3 (FIG. 6), although there are areas where the current density is locally high in each frequency band, such as the 800 MHz band, there are no sides where the current density is uniformly high among the sides that make up the antenna section 30 and the ground section 40.

[0054] Furthermore, the VSWR measurement results (Figure 7) for Antenna 3 showed values ​​of approximately 2 or less in frequency bands such as the 900 MHz band, and values ​​of approximately 3 in some frequency bands such as the 800 MHz band. This indicates that Antenna 3 has good performance as an antenna, or functions satisfactorily as an antenna, in these frequency bands.

[0055] Incidentally, an antenna that combines a resonant antenna and a traveling-wave antenna is known, as described in the above-mentioned Patent Document 1. This antenna is also called a Vivaldi monopole antenna, and has a rod-shaped monopole antenna portion that functions as a standing-wave antenna, and a tapered slot portion with a gradually expanding slot width that functions as a traveling-wave antenna.

[0056] On the other hand, the antenna 3 according to this embodiment does not have a tapered slot structure in which the slot width gradually increases, and as shown in FIG. 7, each part including the antenna part 30 and the ground part 40 functions as a traveling wave antenna.

[0057] From this, it can be considered that the antenna 3 functions as a standing wave antenna and a traveling wave antenna in multiple frequency bands, based on an operating principle that is completely different from that of the well-known Vivaldi monopole antenna.

[0058] According to the above configuration, the antenna 3 of the wireless communication device 1 according to this embodiment includes an antenna section 30 having a first antenna element 31, a second antenna element 32, and a third antenna element 33 on the antenna front surface 3A, a ground section 40, and a slit section 50 formed between them. The antenna 3 also includes a back-side ground section 60 formed on the second conductive layer 22 on the antenna back surface 3B. Furthermore, the lengths of the sides of the antenna section 30, the ground section 40, and the back-side ground section 60 are different from the lengths that resonate with frequencies such as the 800 MHz band. Therefore, the antenna 3 can function well as a traveling-wave antenna without resonating with supplied electrical signals in these frequency bands. Thus, the antenna 3 can achieve good characteristics in multiple frequency bands despite its relatively small, thin-plate configuration.

[0059] 5. Other Embodiments In the above-described embodiment, the length LX31 of the first antenna element 31 is greater (longer) than the length LX32 of the second antenna element 32 and the length LX33 of the third antenna element 33 in the X direction of the antenna surface 3A (FIG. 4), and the lengths LX32 and LX33 are equal. However, the present invention is not limited to this. For example, the length LX31 may be equal to the lengths LX32 and LX33 in the X direction, or the lengths LX32 and LX33 may be different from each other. Furthermore, among the lengths LX31, LX32, and LX33, either the length LX32 or LX33 may be the greatest (longest). The key point is that the antenna functions as a traveling-wave antenna in the intended frequency band (e.g., the 800 MHz band) and exhibits favorable characteristics as shown in FIGS. 7 and 8.

[0060] In the above-described embodiment, the length LY31 of the first antenna element 31, the length LY32 of the second antenna element 32, and the length LY33 of the third antenna element 33 are all equal in the Y direction of the antenna surface 3A (FIG. 4). Also, the length LY51 of the front slit 51, the length LY52 of the middle slit 52, and the length LY53 of the rear slit 53 are all equal and are shorter than the lengths LY31, LY32, and LY33. However, the present invention is not limited to this. For example, the lengths LY31, LY32, and LY33 may be different from one another in the Y direction, or the lengths LY51, LY52, and LY53 may be different from one another. Furthermore, for example, at least a portion of the lengths LY51, LY52, and LY53 may be equal to or longer than the lengths LY31, LY32, and LY33.

[0061] Furthermore, in the above-described embodiment, the first antenna element 31, the second antenna element 32, and the third antenna element 33 of the antenna unit 30 (FIG. 4) are arranged parallel to each other, i.e., with their long sides parallel to each other. However, the present invention is not limited to this, and for example, at least one of the first antenna element 31, the second antenna element 32, and the third antenna element 33 may be arranged so as not to be parallel to each other.

[0062] Furthermore, in the above-described embodiment, the first antenna element 31, the second antenna element 32, and the third antenna element 33 of the antenna unit 30 are all rectangular, the front slit 51, the middle slit 52, the rear slit 53, etc. are configured to extend substantially along the Y direction, and the right slit 57, etc. are configured to extend substantially along the X direction ( FIG. 4 ). However, the present invention is not limited to this. For example, the right slit 57 may be inclined at a predetermined angle with respect to the Y direction to form the antenna base 34 into a trapezoidal shape. Alternatively, the antenna unit 30 may have various quadrilateral shapes, or various other shapes such as a hexagonal or octagonal shape. Alternatively, the entire shape of the antenna unit 30 may be various polygonal shapes such as a hexagonal or octagonal shape. Furthermore, in these cases, at least some of the sides may be curved rather than straight. In any case, it is sufficient that some of the sides surrounding the antenna unit 30 face the ground portion 40 across the front slit 51, etc., and the remaining sides do not face the ground portion 40.

[0063] Furthermore, in the above-described embodiment, the antenna section 30 (FIG. 4) has been described as having the power feed connection section 35 and the power feed connection terminal 36 provided at a position among the first antenna element 31, the second antenna element 32, and the third antenna element 33 that is closest to the first antenna element 31. However, the present invention is not limited to this, and the power feed connection section 35 and the power feed connection terminal 36 may be provided at a position closest to the second antenna element 32 or the third antenna element 33, for example.

[0064] In the above-described embodiment, a notch is provided in the lower portion of the left side of the right gland 44 of the ground section 40 to surround the power supply connection part 35 and the power supply connection terminal 36 (FIG. 4). However, the present invention is not limited to this, and for example, the power supply connection part 35 and the power supply connection terminal 36 may be provided adjacent to the left side of the left side of the right gland 44 without providing a notch.

[0065] Furthermore, in the above-described embodiment, a case has been described in which a back-surface ground section 60 having a shape similar to that of the ground section 40 projected onto the antenna back surface 3B is provided, and the back-surface ground section 60 and the ground section 40 are electrically connected by vias 28 (FIGS. 3 to 5). However, the present invention is not limited to this, and for example, the back-surface ground section 60 may have various shapes different from those of the ground section 40, or the back-surface ground section 60 and the ground section 40 may be electrically separated, or the back-surface ground section 60 may even be omitted.

[0066] Furthermore, in the above-described embodiment, the antenna functions as a traveling wave antenna in six frequency bands, namely, the 800 MHz band, the 900 MHz band, the 1.5 GHz band, the 1.7 GHz band, the 2 GHz band, and the 2.6 GHz band (FIG. 6). However, the present invention is not limited to this, and the antenna may function as a traveling wave antenna in various other frequency bands.

[0067] Furthermore, in the above-described embodiment, the antenna 3 is configured using a glass epoxy substrate conforming to the FR-4 standard of the NEMA / ANSI. However, the present invention is not limited to this, and the antenna 3 may be configured using various other substrates.

[0068] Furthermore, the present invention is not limited to the above-described embodiments and other embodiments, and the scope of application of the present invention extends to embodiments in which the above-described embodiments and other embodiments are combined in part or in whole, or in which only a part of the above-described embodiments is extracted.

[0069] Furthermore, in the above-described embodiment, the antenna 3 is configured as an antenna by the antenna portion 30 as an antenna portion, the ground portion 40 as a ground portion, and the slit portion 50 as a slit portion. However, the present invention is not limited to this, and the antenna may be configured by an antenna portion, a ground portion, and a slit portion having various other configurations. [Industrial Applicability]

[0070] The present invention can be used in antennas for wireless communication devices that support communication standards such as 5G. [Explanation of symbols]

[0071] 1...wireless communication device, 3...antenna, 3A...antenna surface, 3B...antenna back surface, 3C...notch, 4...connection cable, 20...base layer, 21...first conductive layer, 22...second conductive layer, 25...connector, 28...via, 30...antenna portion, 31...first antenna element, 32...second antenna element, 33...third antenna element, 34...antenna base, 35...power supply connection portion, 36...power supply connection terminal, 40...ground portion, 41...front ground, 42...left front ground, 43...left rear ground, 44...right ground, 45...ground connection terminal, 50...slit portion, 51...front slit, 52...center slit, 53...rear slit, 54...left front slit, 55...left center slit, 56...left rear slit, 57...right slit, 60...back ground portion.

Claims

1. an antenna portion formed on a surface of the substrate and having three antenna elements; a ground portion formed around the antenna portion on the surface of the substrate and facing a part of the antenna portion; a slit portion formed on the surface of the substrate between the antenna portion and the ground portion; Equipped with The antenna portion and the ground portion do not resonate at a plurality of predetermined frequencies. An antenna characterized by:

2. The three antenna elements are composed of a first antenna element, a second antenna element, and a third antenna element each formed in a rectangular shape on the surface of the substrate.

2. The antenna according to claim 1 .

3. The long side of the first antenna element is longer than the long sides of the second antenna element and the third antenna element.

3. The antenna according to claim 2.

4. The slit portion is formed between the long side of the first antenna element and the ground portion.

4. The antenna according to claim 3.

5. The long sides of the second antenna element and the third antenna element have the same length.

3. The antenna according to claim 2.

6. In the antenna unit, a distance from a power supply point that supplies power to the first antenna element is shorter than a distance from the power supply point to the second antenna element and a distance from the power supply point to the third antenna element.

3. The antenna according to claim 2.

7. The three antenna elements are arranged so that their long sides are parallel to each other.

3. The antenna according to claim 2.

8. The three antenna elements have the same short side length.

8. The antenna according to claim 7.

9. In the antenna unit, the distance between the antenna elements is shorter than the length of the short side of the antenna elements.

9. The antenna according to claim 8.

10. The slit portion has a distance between the antenna portion and the ground portion that is shorter than the length of the short side of the antenna element.

9. The antenna according to claim 8.

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