CN104852129A - Antenna device - Google Patents

Abstract

The present invention relates to an antenna device capable of obtaining required insulation even if it is small and integrates a plurality of antennas. The roughly central parts of the first element (11) and the second element (12) are bent into a reverse "く" shape, so that the distance between the first element (11) and the second element (12) becomes larger at the roughly central part. In addition, the opposing angle θ1 between the pattern of the first feeding matching portion (11b) and the pattern of the second feeding matching portion (12b) is set to about 90°. With this configuration, an insulation characteristic of -10 db or higher can be obtained in the design frequency band.

Description

Antenna device

technical field

The present invention relates to a miniaturized antenna device including a plurality of antenna elements arranged close to each other.

Background technique

In recent years, with the popularization of LTE (Long Term Evolution, long-term evolution) communication modules, the development of antennas that can support MIMO (Multiple Input Multiple Output) has become a top priority. LTE is one of the mobile phone communication standards. It is a standard that further speeds up the communication standard (3G) of the third-generation mobile phone that is currently becoming the mainstream. is set to 50Mbps or more. Therefore, MIMO, which is a wireless communication technology that combines a plurality of antennas to widen the frequency band for data transmission and reception, is incorporated into the LTE communication module. In MIMO, multiple antennas transmit different data at the same time, and combine them at the time of reception to virtually realize a wide frequency band and realize high-speed communication. In theory, it is possible to obtain the same effect as increasing the bandwidth by 2 times with 2 antennas and increasing the bandwidth by 3 times with 3 antennas. The improvement in throughput achieved by the MIMO technology is achieved by mounting a plurality of antennas.

In an antenna device compatible with MIMO, it is difficult to downsize because it includes a plurality of elements. If it is downsized, the elements are arranged close to each other, and the insulation between the elements may be deteriorated. As conventional MIMO-compatible antenna devices, Patent Document 1 to Patent Document 3 describe small-sized MIMO antenna devices capable of ensuring insulation between two antenna elements.

prior art literature

patent documents

Patent Document 1: Japanese Patent Laid-Open No. 2012-182536

Patent Document 2: Japanese Unexamined Patent Publication No. 2007-97167

Patent Document 3: Japanese Patent Laid-Open No. 2011-77608

Contents of the invention

FIG. 29 shows the configuration of an example of a conventional antenna device compatible with MIMO. In the antenna device 100 shown in FIG. 29 , a first element 111 is formed on the front surface of a substrate 110 , and a second element 112 is formed on the back surface of the substrate 110 . The first element 111 and the second element 112 have the same shape and are substantially overlapped with each other via the substrate 110 . The structure of the front surface of the substrate 110 and the structure of the back surface of the substrate 110 have a symmetrical shape. The lower end of the first element 111 is connected to the first power supply matching portion 111b, and the upper end is connected to the first shortening coil 111a. In the middle of the first element 111, an inverted triangular widened portion is formed. In addition, the lower end of the second element 112 is connected to the second power supply matching part 112b, and the second shortening coil 112a is connected to the upper end. Also in the middle of the second element 112, a widened portion having an inverted triangle shape is formed.

The illustrated length L20 is the physical length from the front end to the lower end of the first element 111 including the first shortening coil 111a or the second element 112 including the second shortening coil 112a, when the design frequency band of the antenna device 100 is set to 814MHz From ~894MHz, if the wavelength of 830MHz is expressed as λ, the length L20 is set to about 0.324λ (about 117mm). At this time, the electrical length between the first element 111 including the first shortening coil 111a and the second element 112 including the second shortening coil 112a is approximately λ/2. In this way, the first element 111 and the second element 112 serve as a dipole antenna that feeds power (voltage feeds) at the ends of an electrical length of approximately λ/2. In the dipole antenna fed from the tip, since the impedance of the feed point becomes high, the first element 111 is supplied with power from a feed line not shown, and the second feed matching portion 112b The second element 112 is supplied with power from a power supply line not shown in the figure to obtain matching.

Fig. 30 (a) shows the frequency characteristics of the insulation between the first element 111 and the second element 112 of the conventional antenna device 100 with the length L20 set to the above-mentioned length, and Fig. 30 (b) shows the frequency characteristics of the first element 111. Regarding the frequency characteristics of the voltage standing wave ratio (VSWR), FIG. 30( c ) shows the frequency characteristics of the VSWR of the second element 112 . Referring to these figures, in the design frequency band of 814MHz to 894MHz, insulation can be obtained at about -6db or more. In addition, in the design frequency band of 814 MHz to 894 MHz, the first element 111 obtains a VSWR of approximately 2.2 or less, and the second element 112 obtains a VSWR of approximately 2.5 or less. The poor insulation properties are considered to be due to the fact that the first element 111 and the second element 112 are arranged close to each other only by the thickness of the substrate 110 , and are arranged opposite to each other so as to overlap with the substrate 110 interposed therebetween.

As the insulation between the two elements, insulation of -10db or more is required. In order to ensure the insulation of -10db or more, FIG. An example structure. In the antenna device 200 shown in FIG. 31 , a first element 211 is formed on the left side of one surface of a substrate 210 having a widened lateral width, and a second element 212 is formed on the right side. The first element 211 and the second element 212 have the same shape and are formed line-symmetrically on both sides of the substrate 210 . The lower end of the first element 211 is connected to the first power supply matching portion 211b, and the upper end is connected to the first shortening coil 211a. In the middle of the first element 211, an inverted triangular widened portion is formed. In addition, the lower end of the second element 212 is connected to the second power supply matching part 212b, and the second shortening coil 212a is connected to the upper end. Also in the middle of the second element 212, an inverted triangular widened portion is formed.

The length L21 shown in the figure is the physical length from the front end to the lower end of the first element 211 including the first shortening coil 211a or the second element 212 including the second shortening coil 212a. At 894MHz, if the wavelength of 830MHz is expressed as λ, the length L21 is set to be about 0.324λ (about 117mm). At this time, the electrical length between the first element 211 including the first shortening coil 211a and the second element 212 including the second shortening coil 212a is approximately λ/2. In addition, the length L22 is the distance between the first element 211 and the second element 212, and is set to about 0.112λ (about 40 mm). In this way, the first element 211 and the second element 212 serve as dipole antennas that are fed (voltage fed) to the ends of the electrical length of approximately λ/2. In the dipole antenna fed from the tip, the impedance of the feeding point becomes high, so the first element 211 is fed from a feeding line not shown in the figure by matching with the first feeding matching part 211b, and the second feeding matching part 212b The second element 212 is supplied with power from a power supply line not shown in the figure to obtain matching.

Fig. 32(a) shows the frequency characteristics of the insulation between the first element 211 and the second element 212 of the conventional antenna device 200 in which the length L21 is set to the above-mentioned length, and Fig. 32(b) shows the frequency characteristics of the first element 32( c ) shows the frequency characteristics of the VSWR of the second element 212 . Referring to these figures, in the design frequency band of 814MHz to 894MHz, insulation can be obtained at about -10db or more. In addition, in the design frequency band of 814 MHz to 894 MHz, the first element 211 obtains a VSWR of approximately 1.8 or less, and the second element 212 obtains a VSWR of approximately 2.0 or less. In this way, if the distance L22 between the antennas is increased, the insulation improves, so it can be seen that the distance between the antennas is very important. In addition, improvement of VSWR characteristics is considered to depend on improvement of insulation characteristics.

If the conventional antenna device 100 shown in FIG. 29 is compared with the conventional antenna device 200 shown in FIG. 31, there is a problem that although the width of the substrate can be reduced, the required insulation cannot be obtained. , If the size of the substrate that can obtain the required insulation is provided with a space between the two elements, it will not be possible to reduce the size. In an antenna device compatible with MIMO, it is required to reduce the space of the installation position, to reduce the size of the antenna in terms of design, and to improve the insulation between the antennas.

Therefore, an object of the present invention is to provide an antenna device that can obtain required insulation even if it is small and integrates a plurality of antennas.

The most important feature of the antenna device according to the present invention is that it includes: a substrate having a narrow, elongated rectangular shape; a pattern of the first element formed on the surface of the substrate; and a pattern formed on the back surface of the substrate. The pattern of the second element having substantially the same shape as the first element; the pattern of the first power supply matching part formed on the lower part of the substrate and connected to the lower end of the first element; and the pattern formed on the substrate The pattern of the second power supply matching part at the lower part and connected to the lower end of the second element bends the approximate central part of the first element and the second element so that the first element and the second The intervals between the elements become larger approximately at the center.

In the antenna device of the present invention, the substantially central portion of the first element and the second element is bent so that the distance between the first element and the second element becomes larger at the substantially central portion, so even if it is small and integrates a plurality of antennas, It is also possible to obtain sufficient insulation characteristics and VSWR characteristics required for operation in the designed frequency band.

Description of drawings

FIG. 1 is a diagram showing the configuration of an antenna device according to a first embodiment of the present invention.

FIG. 2 is a diagram showing another structure of the antenna device according to the first embodiment of the present invention.

FIG. 3 is a graph showing insulation characteristics and VSWR characteristics of the antenna device according to the first embodiment of the present invention.

FIG. 4 is a diagram showing the configuration of an antenna device according to a second embodiment of the present invention.

FIG. 5 is a graph showing insulation characteristics and VSWR characteristics of the antenna device according to the second embodiment of the present invention.

FIG. 6 is a diagram showing the configuration of an antenna device according to a third embodiment of the present invention.

FIG. 7 is a graph showing insulation characteristics and VSWR characteristics of an antenna device according to a third embodiment of the present invention.

FIG. 8 is a diagram showing a configuration of a first substrate in an antenna device according to a fourth embodiment of the present invention.

9 is a diagram showing another configuration of the first substrate in the antenna device according to the fourth embodiment of the present invention.

FIG. 10 is a diagram showing the configuration of a second substrate and a third substrate in an antenna device according to a fourth embodiment of the present invention.

11 is a diagram showing a configuration in which a second substrate and a third substrate are assembled in an antenna device according to a fourth embodiment of the present invention.

12 is a diagram showing the structure of an antenna device according to a fourth embodiment of the present invention by mounting a second substrate and a third substrate on a first substrate to obtain an antenna device according to a fourth embodiment of the present invention.

FIG. 13 is a graph showing insulation characteristics and VSWR characteristics of the antenna device according to the fourth embodiment of the present invention.

14 is a graph showing another insulation characteristic and VSWR characteristic of the antenna device according to the fourth embodiment of the present invention.

Fig. 15 is a graph showing yet another insulation characteristic and VSWR characteristic of the antenna device according to the fourth embodiment of the present invention.

Fig. 16 is a diagram showing the configuration of an antenna device according to a fifth embodiment of the present invention.

Fig. 17 is a graph showing insulation characteristics and VSWR characteristics of the antenna device according to the fifth embodiment of the present invention.

FIG. 18 is a diagram showing the configuration of an antenna device according to a first reference example of the present invention.

19 is a graph showing insulation characteristics and VSWR characteristics of the antenna device of the first reference example according to the present invention.

FIG. 20 is a diagram showing the configuration of an antenna device according to a second reference example of the present invention.

21 is a graph showing insulation characteristics and VSWR characteristics of an antenna device according to a second reference example of the present invention.

FIG. 22 is a diagram showing the configuration of an antenna device according to a third reference example of the present invention.

23 is a graph showing insulation characteristics and VSWR characteristics of an antenna device according to a third reference example according to the present invention.

FIG. 24 is a diagram showing the configuration of an antenna device according to a fourth reference example of the present invention.

FIG. 25 is a graph showing insulation characteristics and VSWR characteristics of an antenna device according to a fourth reference example according to the present invention.

Fig. 26 is a diagram showing the configuration of an antenna device according to a sixth embodiment of the present invention.

Fig. 27 is an exploded view showing the configuration of an antenna device according to a sixth embodiment of the present invention.

Fig. 28 is another exploded view showing the configuration of the antenna device according to the sixth embodiment of the present invention.

FIG. 29 is a diagram showing the configuration of a conventional antenna device.

FIG. 30 is a graph showing insulation characteristics and VSWR characteristics of a conventional antenna device.

FIG. 31 is a diagram showing the configuration of another conventional antenna device.

FIG. 32 is a graph showing insulation characteristics and VSWR characteristics of another conventional antenna device.

Symbol Description

1, 2, 3, 4, 5, 6, 6', 7, 8, 9 antenna device, 10 substrate, 10a round hole, 10b square hole, 10c notch, 10d first groove, 10e second groove, 11 the first element, 11a the first shortened coil, 11b the first power supply matching part, 12 the second element, 12a the second shortened coil, 12b the second power supply matching part, 21a the first power supply matching part, 22a the second power supply matching part, 31 first element, 31a first shortened coil, 31b first power supply matching part, 32 second element, 32a second shortened coil, 32b second power supply matching part, 40 first substrate, 40a first long hole, 40b second Long hole, 40c hypotenuse, 40d first groove, 40e second groove, 41 first element, 41a first shortening coil, 41b first power supply matching part, 42 second element, 42a second shortening coil, 42b first 2 Power supply matching part, 44 2nd substrate, 44a insert piece, 44b convex part, 44c concave part, 44d convex part, 44e convex part, 44f hypotenuse, 44g mating part, 45 3rd component, 45a 3rd component, 45b 3rd component Element, 45c 3rd element, 46 4th element, 46a 4th element, 46b 4th element, 47 3rd substrate, 47a insertion hole, 47b recess, 47c protrusion, 47d recess, 47e recess, 47f bevel, 47g fit sheet, 47h pressing piece, 48a the third shortening coil, 48b the fourth shortening coil, 49a the third power supply matching part, 49b the fourth power supply matching part, 50 substrate, 50c notch part, 51 the first element, 51a the first shortening coil, 51b first power supply matching part, 52 second element, 52a second shortening coil, 52b second power supply matching part, 60 substrate, 61, 61' first element, 61a first shortening coil, 61b first power supply matching part, 62 , 62' the second element, 62a the second shortened coil, 62b the second power supply matching part, 70 substrate, 71 the first element, 71a the first shortened coil, 71b the first power supply matching part, 72 the second element, 72a the second shortened Coil, 72b second power supply matching part, 80 substrate, 81 first element, 81a first shortened coil, 81b first power supply matching part, 82 second element, 82a second shortened coil, 82b second power supply matching part, 90 frame Body, 91 cover, 91a bottom, 91b both sides, 91c convex rib, 91d convex rib, 91e pressing rib, 91f joint piece, 92 base, 92a round boss, 92b square boss, 92c bottom plate, 92c bottom, 92d joint part, 93a coaxial cable, 93b coaxial cable, 100 antenna device, 110 substrate, 111 first element, 111a first shortening coil, 111b first power supply matching part, 112 second element, 112a second shortening coil, 112b the second power supply matching part, 200 antenna device, 210 substrate, 211 the first element, 211a the first shortening coil, 211b the first power supply matching part, 212 the second element, 2 12a the second shortening coil, 212b the second power supply matching part

Detailed ways

1 and 2 show the configuration of an antenna device according to a first embodiment of the present invention. FIG. 1 is a diagram showing the configuration of the front surface of the antenna device 1 of the first embodiment, and FIG. 2 is a diagram showing the configuration of the rear surface of the antenna device 1 of the first embodiment.

The antenna device 1 of the first embodiment is provided as a MIMO-compatible antenna device and includes two elements. In the antenna device 1 of the first embodiment, as shown in FIGS. 1 and 2 , the substrate 10 having a substrate structure having good high-frequency characteristics such as a glass epoxy substrate and a polytetrafluoroethylene substrate is set so as to have a narrow width. elongated rectangular shape. The pattern of the first element 11 is formed on the surface of the substrate 10 , and the pattern of the second element 12 is formed on the back surface of the substrate 10 . The first element 11 is formed in an inverse triangular shape such that the substantially central part is bent in a reverse "く" shape and gradually widened from the lower end toward the upper end, and is formed in an elongated shape at the upper end. The second element 12 has the same shape as the first element 11 and is formed to face each other with the substrate 10 interposed therebetween. The structure of the front surface of the substrate 10 is symmetrical to the structure of the back surface. In this case, the first element 11 and the second element 12 are formed to intersect with the substrate 10 at the upper part, but the patterns of the two elements do not overlap except for the intersecting portion. The lower end of the first element 11 is connected to the first power supply matching portion 11b, and the upper end is connected to the first shortening coil 11a. In addition, the lower end of the second element 12 is connected to the second power supply matching part 12b, and the second shortening coil 12a is connected to the upper end. The patterns of the first power supply matching portion 11b and the second power supply matching portion 12b are rotated clockwise by about 45° with respect to the substrate 10, and the patterns of the second power supply matching portion 12b are relatively rotated by an angle relative to the pattern of the first power supply matching portion 11b. θ1 is formed. In addition, the matching circuits of the first power supply matching unit 11b and the second power supply matching unit 12b are, for example, π-type LC circuits, and coils and capacitors are welded to the patterns, but the illustrations are omitted, and only the patterns of the matching circuits are shown.

The length L1 shown in FIG. 2 is the physical length from the front end to the lower end of the first element 11 including the first shortening coil 11a or the second element 12 including the second shortening coil 12a, when the design frequency band of the antenna device 1 is set as In the case of 814MHz to 894MHz, if the wavelength of 830MHz is expressed as λ, the length L1 is set to about 0.333λ (about 119mm). At this time, the electrical length between the first element 11 including the first shortening coil 11a and the second element 12 including the second shortening coil 12a is approximately λ/2. In addition, the length L2 is the physical length from the lower end of the first element 11 or the second element 12 to the position where it is bent into an inverted "く" shape, and is set to about 0.162λ (about 58mm). Further, the distance D1 is the distance between the positions where the first element 11 and the second element 12 are bent into an inverted "く" shape, and the distance D1 is set to about 0.022λ (about 8 mm). Furthermore, an angle θ1 of the pattern of the second power supply matching portion 12b with respect to the pattern of the first power supply matching portion 11b is set to approximately 90°.

Here, the first element 11 and the second element 12 serve as a dipole antenna that feeds power (voltage feeds) at the ends of an electrical length of approximately λ/2. In the dipole antenna fed from the tip, the impedance of the feeding point becomes high, so the first element 11 is fed from a feeding line not shown in the figure by matching with the first feeding matching part 11b, and the second feeding matching part 12b The second element 12 is supplied with power from a power supply line not shown in the figure to obtain matching.

Figure 3 (a) shows the frequency characteristics of the insulation between the first element 11 and the second element 12 of the antenna device 1 of the first embodiment in which the lengths L1, L2 and the interval D1 are set to the above-mentioned dimensions, and Fig. 3( b) shows the frequency characteristics of the voltage standing wave ratio (VSWR) of the first element 11 , and FIG. 3( c ) shows the frequency characteristics of the VSWR of the second element 12 . Referring to these figures, in the design frequency band of 814 MHz to 894 MHz, good insulation characteristics of about -12 db or higher can be obtained for the insulation. In addition, in the design frequency band of 814MHz to 894MHz, the VSWR characteristic of the first element 11 is within approximately 3.0 and is set to resonate at approximately 845MHz, and the VSWR characteristic of the second element 12 is within approximately 3.0 and is set to be within approximately 3.0. 850MHz resonant VSWR characteristic. In this way, in the antenna device 1 of the first embodiment, the first element 11 and the second element 12 are respectively formed on the front and back surfaces of the narrow substrate 10, and by bending the shapes of the first element 11 and the second element 12 in opposite directions,く" shape, so that they do not substantially overlap each other, and the angle between the first power supply matching part 11b and the second power supply matching part 12b is set to about 90°, so it can be considered that sufficient frequency for operation can be obtained in the above-mentioned designed frequency band. The insulation characteristics and VSWR characteristics.

In addition, a circular hole 10a is formed approximately in the center of the substrate 10, a square hole 10b is formed on both sides of the upper part, and a first groove part 10d is formed on the upper part of the two sides than the center, and a second groove part 10d is formed on the upper side. In the groove portion 10e, notch portions 10c inclined to each other are formed on both sides of the lower end, respectively. These circular holes 10a, square holes 10b, first groove portion 10d, and second groove portion 10e are used for mounting purposes and positioning purposes when housing the antenna device 1 in a housing described later.

Next, FIG. 3 shows the configuration of an antenna device according to a second embodiment of the present invention. FIG. 3 is a diagram showing the structure of the surface of the antenna device 2 of the second embodiment.

The antenna device 2 of the second embodiment is provided as a MIMO-compatible antenna device and includes two elements. As shown in FIG. 3 , the antenna device 2 of the second embodiment differs from the antenna device 1 of the first embodiment in the configuration of the feeding matching section, but other configurations are the same as those of the antenna device 1 of the first embodiment. Here, the description of the feeding matching section of the antenna device 2 according to the second embodiment will be mainly described, and the description of common configurations will be largely omitted. The pattern of the first element 11 is formed on the front surface of the substrate 10 , and the pattern of the second element 12 is formed on the back surface of the substrate 10 . The first element 11 and the second element 12 are formed such that the approximate central portion is bent in an inverted “く” shape and intersect at the upper portion via the substrate 10 , and the two elements do not overlap except for the intersecting portion. The lower end of the first element 11 is connected to the first power supply matching portion 21a, and the upper end is connected to the first shortening coil 11a. In addition, the lower end of the second element 12 is connected to the second power supply matching part 22a, and the second shortening coil 12a is connected to the upper end. The pattern of the first power supply matching portion 21a and the pattern of the second power supply matching portion 22a are formed from the center portion toward one side so that only the approximate center portion overlaps with the substrate 10 interposed therebetween. In addition, the matching circuits of the first power supply matching unit 21a and the second power supply matching unit 22a are, for example, π-type LC circuits, but illustrations of coils and capacitors are omitted, and only patterns of the matching circuits are shown.

The length as the physical length from the front end to the lower end of the first element 11 including the first shortening coil 11a or the second element 12 including the second shortening coil 12a is set to about 0.333λ (about 119mm). The electrical length between the first element 11 of the shortened coil 11a and the second element 12 including the second shortened coil 12a is approximately λ/2. In addition, the physical length from the lower end of the first element 11 or the second element 12 to the position where it is bent in an inverted "く" shape is set to about 0.162λ (about 58 mm). Further, the distance between the positions where the first element 11 and the second element 12 are bent in an inverted "く" shape is set to about 0.022λ (about 8 mm).

Here, the first element 11 and the second element 12 serve as a dipole antenna that feeds power (voltage feeds) at the ends of an electrical length of approximately λ/2. In the dipole antenna fed from the tip, the impedance of the feeding point becomes high, so the first element 11 is fed from a feeding line not shown in the figure by matching with the first feeding matching part 21a, and the second feeding matching part 22a The second element 12 is supplied with power from a power supply line not shown in the figure to obtain matching.

Fig. 5 (a) shows the frequency characteristics of the insulation between the first element 11 and the second element 12 of the antenna device 2 of the second embodiment set to the above-mentioned dimensions, and Fig. 5 (b) shows the first element The frequency characteristic of the voltage standing wave ratio (VSWR) of 11, FIG. 5(c) shows the frequency characteristic of the VSWR of the second element 12. Referring to these figures, in the design frequency band of 814 MHz to 894 MHz, good insulation characteristics of about -10 db or higher can be obtained for the insulation. In addition, in the design frequency band of 814MHz to 894MHz, the VSWR characteristic of the first element 11 is within approximately 3.9 and is set to resonate at approximately 850MHz, and the VSWR characteristic of the second element 12 is within approximately 3.8 and is set to be within approximately 3.8. 850MHz resonant VSWR characteristic. Thus, in the antenna device 2 of the second embodiment, the first element 11 and the second element 12 are respectively formed on the front and back surfaces of the narrow substrate 10, The "く" shapes are reversed so that they do not substantially overlap with each other, so it is considered that sufficient insulation characteristics and VSWR characteristics required for operation can be obtained in the above-mentioned design frequency band.

Next, FIG. 6 shows the configuration of an antenna device according to a third embodiment of the present invention. FIG. 6 is a diagram showing the structure of the surface of the antenna device 3 of the third embodiment.

The antenna device 3 of the third embodiment is provided as a MIMO-compatible antenna device and includes two elements. As shown in FIG. 6, the antenna device 3 of the third embodiment differs from the antenna device 1 of the first embodiment in the configuration of two elements, but the other configurations are the same as those of the antenna device 1 of the first embodiment. Here, the description will be mainly given of the two elements of the antenna device 3 of the third embodiment, and the description of the common configuration will be largely omitted. The surface of the substrate 10 is formed with a pattern of linear first elements 31 having an inverted triangular widened part in the middle, and the back surface of the substrate 10 is formed with a linear first element 31 formed with an inverted triangular widened part in the middle. 2 elements of 32 patterns. The first element 31 and the second element 32 are formed overlappingly so as to face each other with the substrate 10 interposed therebetween. The lower end of the first element 31 is connected to the first power supply matching portion 31b, and the first shortening coil 31a is connected to the upper end. In addition, the lower end of the second element 32 is connected to the second power supply matching part 32b, and the second shortening coil 32a is connected to the upper end. The pattern of the first power supply matching portion 31b and the pattern of the second power supply matching portion 32b are rotated clockwise by about 45° with respect to the substrate 10, and the pattern of the second power supply matching portion 32b is opposite to the pattern of the first power supply matching portion 31b. formed with a rotation of θ2. In addition, the matching circuits of the first power supply matching unit 31b and the second power supply matching unit 32b are, for example, π-type LC circuits, but illustrations of coils and capacitors are omitted, and only patterns of the matching circuits are shown.

The length L3 shown in FIG. 6 is the physical length from the front end to the lower end of the first element 31 including the first shortening coil 31a or the second element 32 including the second shortening coil 32a, when the design frequency band of the antenna device 3 is set as At 814MHz to 894MHz, the length L3 is set to about 0.324λ (about 117mm). At this time, the electrical length between the first element 31 including the first shortening coil 31a and the second element 32 including the second shortening coil 32a is approximately λ/2. In addition, the angle θ2 of the second power supply matching portion 32b with respect to the first power supply matching portion 31b is set to approximately 90°.

Here, the first element 31 and the second element 32 serve as a dipole antenna that feeds power (voltage feeds) at the ends of an electrical length of approximately λ/2. In the dipole antenna fed from the tip, the impedance of the feeding point becomes high, so the first element 31 is fed from a feeding line not shown in the figure by matching with the first feeding matching part 31b, and the second feeding matching part 32b The second element 32 is supplied with power from an unillustrated power supply line to obtain matching.

Fig. 7 (a) shows the frequency characteristics of the insulation between the first element 31 and the second element 32 of the antenna device 3 of the third embodiment in which the length L3 is set to the above-mentioned size, and Fig. 7 (b) shows the first element 31 and the second element 32. The frequency characteristic of the voltage standing wave ratio (VSWR) of the first element 31, FIG. 7(c) shows the frequency characteristic of the VSWR of the second element 32. Referring to these figures, in the design frequency band of 814MHz to 894MHz, the insulation can obtain an insulation characteristic of about -9db or more. In addition, in the design frequency band of 814MHz to 894MHz, the VSWR characteristic of the first element 31 is within about 2.2 and is set to resonate at about 810MHz, and the VSWR characteristic of the second element 32 is within about 2.0 and is set to be within about 2.0. 820MHz resonant VSWR characteristic. In this way, in the antenna device 3 of the third embodiment, the first element 31 and the second element 32 are formed to overlap each other on the front and back surfaces of the narrow substrate 10, and the first power supply matching part 31b and the second power supply matching part 31b Since the angle of the matching portion 32b is set to approximately 90°, it is considered that sufficient insulation characteristics and VSWR characteristics required for operation can be obtained in the above-mentioned designed frequency band.

Next, FIGS. 8 to 12 show the configuration of an antenna device according to a fourth embodiment of the present invention. 8 is a diagram showing the structure of the surface of the first substrate 40 in the antenna device 4 of the fourth embodiment, and FIG. 9 is a diagram showing the structure of the back surface of the first substrate 40 in the antenna device 4 of the fourth embodiment. Figure 10 (a), (b) is a diagram showing the structure of the surface of the second substrate 44 and the third substrate 47 in the antenna device 4 of the fourth embodiment, and Fig. 11 shows the structure of the surface of the fourth embodiment 12 is a diagram showing a structure in which the second substrate 44 and the third substrate 47 are assembled in the antenna device 4. FIG. The structure diagram of the antenna device 4 of the example.

The antenna device 4 of the fourth embodiment is provided as a MIMO-compatible antenna device and includes four elements formed on a first substrate 40 , a second substrate 44 , and a third substrate 47 . The structure of the first substrate 40 in the antenna device 4 of the fourth embodiment is the same as that of the substrate 10 of the antenna device 1 of the first embodiment, as shown in FIGS. 8 and 9 . That is, the pattern of the first element 41 is formed on the surface of the first substrate 40 made of a base material such as a glass epoxy substrate, a polytetrafluoroethylene substrate, etc., and a second element 41 is formed on the back surface of the first substrate 40. The pattern of the element 42. The first element 41 is formed in an anti-triangular shape such that its substantially central portion is bent in an inverted “く” shape, gradually widening from the lower end toward the upper end, and is formed in an elongated shape at the upper end. The second element 42 has the same shape as the first element 41 and is formed to face each other with the first substrate 40 interposed therebetween. The structure of the front surface of the first substrate 40 is symmetrical to the structure of the back surface. In this case, the first element 41 and the second element 42 are formed to intersect with each other with the first substrate 40 interposed therebetween, and the two elements do not overlap except for the intersecting portion. The lower end of the first element 41 is connected to the first power supply matching part 41b, and the first shortening coil 41a is connected to the upper end. In addition, the lower end of the second element 42 is connected to the second power supply matching part 42b, and the second shortening coil 42a is connected to the upper end. The pattern of the first power supply matching portion 41b and the pattern of the second power supply matching portion 42b are rotated clockwise by about 45° with respect to the first substrate 40, and the pattern of the second power supply matching portion 42b is opposite to that of the first power supply matching portion 41b. The pattern is formed with rotation angle θ3. In addition, the matching circuits of the first power supply matching unit 41b and the second power supply matching unit 42b are, for example, π-type LC circuits, but illustrations of coils and capacitors are omitted, and only patterns of the matching circuits are shown.

The length L4 shown in FIG. 9 is the physical length from the front end to the lower end of the first element 41 including the first shortening coil 41a or the second element 42 including the second shortening coil 42a, when the design frequency band of the antenna device 4 is set as In the case of 814MHz to 894MHz, if the wavelength of 830MHz is expressed as λ, the length L4 is set to about 0.333λ (about 119mm). At this time, the electrical length between the first element 41 including the first shortening coil 41 a and the second element 42 including the second shortening coil 42 a is approximately λ/2. In addition, the length L5 is the physical length from the lower end of the first element 41 or the second element 42 to the position where it is bent in an inverted "く" shape, and is set to about 0.162λ (about 58 mm). Further, the distance D4 is the distance between the positions where the first element 41 and the second element 42 are bent into an inverted "く" shape, and the distance D4 is set to about 0.034λ (about 12mm). Furthermore, the angle θ3 of the pattern of the second power supply matching portion 42b with respect to the pattern of the first power supply matching portion 41b is set to approximately 90°.

Here, the first element 41 and the second element 42 serve as a dipole antenna that feeds power (voltage feeds) at the ends of an electrical length of approximately λ/2. In a dipole antenna fed from an end portion, since the impedance of the feeding point becomes high, the first element 41 is fed from an unillustrated feeding line to obtain matching by the first feeding matching part 41b, and the second feeding matching part 42b The second element 42 is supplied with power from an unillustrated power supply line to obtain matching.

In addition, on the approximate central axis of the first substrate 40, a narrow first elongated hole 40a and a second elongated hole 40b are formed, and a first groove portion 40d is formed in the approximate center of the upper side, and mutually formed on both sides of the lower portion. The inclined hypotenuse 40c has a second groove portion 40e formed on the lower side thereof. These first elongated holes 40 a , second elongated holes 40 b , first groove portion 40 d , and second groove portion 40 e are used when mounting a second substrate 44 and a third substrate 47 described later on the first substrate 40 .

Next, the structure of the second substrate 44 in the antenna device 4 of the fourth embodiment is as shown in FIG. Structure. That is, the second substrate 44 made of a base material having good high-frequency characteristics such as a glass epoxy substrate and a polytetrafluoroethylene substrate is formed in an elongated approximately rectangular shape, and the upper end width is small on the right side of the second substrate 44. The insertion piece 44a is formed so as to protrude in the lateral direction, a rectangular-shaped convex portion 44b is formed above the central portion, a rectangular-shaped concave portion 44c is formed below it, and a rectangular-shaped convex portion 44d is formed below it, Below it, a rectangular-shaped convex portion 44e is formed. The lower left side of the second substrate 44 is formed as a beveled side 44f, and a fitting portion 44g is formed at the lower end. On the surface of the second substrate 44, the third element 45a corresponding to the upper part of the third element 45 divided into three parts is formed obliquely upward from the convex part 44b, and the third element 45c corresponding to the lower part is formed obliquely upward from the convex part 44e. formed obliquely downward. On the back surface of the second substrate 44 is formed an inverted "く"-shaped fourth element 46b corresponding to the central portion and the lower portion of the fourth element 46 divided into two. In addition, the third shortening coil 48a is formed on the upper part of the second substrate 44, one of the patterns of the third power supply matching part 49a divided into two parts is formed on the lower part of the surface, and the second power supply matching part 49a divided into two parts is formed on the lower part of the back surface. One of the patterns of the fourth feeding matching portion 49b.

In addition, the structure of the third substrate 47 in the antenna device 4 of the fourth embodiment is, as shown in FIG. . That is, the third substrate 47 made of a base material having good high-frequency characteristics such as a glass epoxy substrate and a polytetrafluoroethylene substrate is formed in an elongated substantially rectangular shape, and the upper end width is small on the left side of the third substrate 47. The pressing piece 47h is formed to be convex in the lateral direction, and below it, a narrow insertion hole 47a is formed in the lateral direction, and a rectangular concave portion 47b is formed above the center portion, and a rectangular convex portion is formed below it. Below the portion 47c, a rectangular recess 47d is formed, and below it, a rectangular recess 47e is formed. The lower right side of the third substrate 47 is formed as a beveled side 47f, and a fitting piece 47g is formed at the lower end. On the surface of the third substrate 47, an inverted "く"-shaped third element 45b corresponding to the central portion of the third element 45 divided into three is formed on the convex portion 47c and the concave portion 47d. On the rear surface of the third substrate 47, a fourth element 46a corresponding to the upper portion of the divided fourth element 46 is formed obliquely. In addition, the fourth shortening coil 48b is formed on the upper part of the third substrate 47, the other of the patterns of the third power supply matching part 49a divided into two parts is formed on the lower part of the surface, and the second part of the pattern divided into two parts is formed on the lower part of the back surface. Another pattern of the two-part fourth power supply matching part 49a.

FIG. 11 shows a structure in which the second substrate 44 and the third substrate 47 shown in FIGS. 10( a ) and ( b ) are assembled. After the left side of the 3rd substrate 47 is docked to the right side of the 2nd substrate 44, it can be assembled. When assembling, the convex portion 44b, concave portion 44c, and convex portion 44e of the 2nd substrate 44 are fitted to the 3rd substrate 44 respectively. The concave portion 47b, convex portion 47c, and concave portion 47e of the substrate 47, and the insertion piece 44a of the second substrate 44 are pressed by the pressing piece 47h of the third substrate 47 to be inserted into the insertion hole 47a, and the mating piece 47g of the third substrate 47 is fitted. to the mating portion 44g of the second substrate 44 . When the second substrate 44 and the third substrate 47 are assembled, it becomes substantially the same structure as the first substrate 40 shown in FIGS. The third elements 45a, 45b, and 45c are continuously formed, and form the third element 45 whose substantially central portion is bent in an inverted "く" shape. The connection points of the third elements 45a, 45b, and 45c can be electrically connected by soldering, and the third element 45 is formed in an inverted triangle shape in such a manner that the width gradually becomes wider from the lower end toward the upper end, and is formed in an elongated shape at the upper end. . In addition, fourth elements 46a, 46b formed on the second substrate 44 and third substrate 47 divided into two on the rear surface are continuously formed, and the fourth element 46 is formed with an approximately central portion bent in an inverted "く" shape. The connection points of the fourth elements 46a and 46b can be electrically connected by soldering, and the fourth element 46 is formed in an inverted triangle shape such that the width gradually becomes wider from the lower end toward the upper end, and is formed in an elongated shape at the upper end.

In this way, the fourth element 46 is set to have the same shape as the third element 45, and is formed opposite to each other with the assembled second substrate 44 and third substrate 47 interposed therebetween, and the surfaces of the assembled second substrate 44 and third substrate 47 are The structure of the structure and the structure of the back are symmetrical shapes. In this case, the third element 45 and the fourth element 46 are formed to intersect with the assembled second substrate 44 and third substrate 47 on top of each other, and the two elements do not overlap except for the intersecting portion. . The lower end of the third element 45 is connected to the third power supply matching portion 49a, and the third shortening coil 48a is connected to the upper end. In addition, the lower end of the fourth element 46 is connected to the fourth power supply matching portion 49b, and the fourth shortening coil 48b is connected to the upper end. The pattern of the 3rd power supply matching part 49a and the pattern of the 4th power supply matching part 49b are rotated about 45 degrees to the right with respect to the 2nd board|substrate 44 and the 3rd board|substrate 47, and the pattern of the 4th power feeding matching part 49b is opposite to the pattern of the 3rd board|substrate 47. 3. The pattern of the feeding matching portion 49a is formed by rotating the angle θ4. In addition, although the matching circuits of the third power supply matching unit 49a and the fourth power supply matching unit 49b are, for example, π-type LC circuits, illustrations of coils and capacitors are omitted, and only patterns of the matching circuits are shown.

The length L6 shown in FIG. 11 is the physical length from the front end to the lower end of the third element 45 including the third shortening coil 48a or the second element 46 including the fourth shortening coil 48b, when the design frequency band of the antenna device 4 is set as In the case of 814MHz to 894MHz, if the wavelength of 830MHz is expressed as λ, the length L6 is set to about 0.333λ (about 119mm). At this time, the electrical length of the third element 45 including the third shortening coil 48 a and the fourth element 46 including the fourth shortening coil 48 b is approximately λ/2. In addition, the length L7 is the physical length from the lower end of the third element 45 or the fourth element 46 to the position where it is bent into an inverted "く" shape, and is set to about 0.162λ (about 57mm). Further, the distance D5 is the distance between the positions where the third element 45 and the fourth element 46 are bent in an inverted "く" shape, and the distance D5 is set to about 0.034λ (about 12 mm). Furthermore, an angle θ4 of the pattern of the fourth power supply matching portion 49b with respect to the pattern of the third power supply matching portion 49a is set to approximately 90°.

Here, the third element 45 and the fourth element 46 serve as dipole antennas with an electrical length of approximately λ/2 for end-feeding (voltage feeding). In the dipole antenna fed from the end, the impedance of the feeding point becomes high, so the matching is obtained by the third feeding matching part 49a, and the third element 45 is fed from a feeding line not shown, and b is fed through the fourth feeding matching part 49 is matched to supply power to the fourth element 46 from a power supply line not shown.

The antenna device 4 of the fourth embodiment is assembled by attaching the second substrate 44 and the third substrate 47 to the first substrate 40 . FIG. 12 shows how the antenna device 4 of the fourth embodiment is assembled by attaching the second substrate 44 and the third substrate 47 to the first substrate 40 . As shown in the figure, on both sides of the first substrate 40 arranged in the vertical direction, the second substrate 44 and the third substrate 47 arranged in the horizontal direction are arranged. Then, the convex portion 47c of the third substrate 47 and the convex portion 44b of the second substrate 44 are inserted into the first elongated hole 40a of the first substrate 40, and the convex portion 44e of the second substrate 44 is inserted into the first elongated hole 40a of the first substrate 40. The second elongated hole 40 b sandwiches the first substrate 40 between the second substrate 44 and the third substrate 47 . At this time, the convex portion 44b, concave portion 44c, and convex portion 44e of the second substrate 44 are respectively fitted into the concave portion 47b, convex portion 47c, and concave portion 47e of the third substrate 47, and the insertion piece 44a of the second substrate 44 passes through the first substrate 40. The first groove portion 40d is inserted into the insertion hole 47a of the third substrate 47 by being pressed by the pressing piece 47h passed from the opposite side in the first groove portion 40d, and the engaging piece 47g of the third substrate 47 is inserted through the first substrate. The second groove portion 40e of 40 is fitted to the fitting portion 44g of the second substrate 44 . Thus, the second substrate 44 and the third substrate 47 are integrally fastened substantially perpendicularly to the first substrate 40 , and the antenna device 4 of the fourth embodiment is assembled.

In addition, the first element 41 and the second element 42 are formed around the first elongated hole 40 a and the second elongated hole 40 b so as to avoid the element pattern so as not to be short-circuited with the third element 45 and the fourth element 46 .

13(a) shows the frequency characteristics of the insulation between the first element 41 and the second element 42 of the antenna device 4 of the fourth embodiment in which the lengths L4 to L7 and the intervals D4 and D5 are set to the above-mentioned dimensions. FIG. 13( b ) shows the frequency characteristic of VSWR of the first element 41 , and FIG. 13( c ) shows the frequency characteristic of VSWR of the second element 42 . Referring to these figures, in the design frequency band of 814 MHz to 894 MHz, good insulation characteristics of about -10 db or higher can be obtained for the insulation. In addition, in the design frequency band of 814 MHz to 894 MHz, the VSWR characteristic of the first element 41 is within about 3.0 and is set to resonate at about 850 MHz, and the VSWR characteristic of the second element 42 is within about 2.8 and is set to be within about 2.8. VSWR characteristics of 855MHz resonance.

In addition, FIG. 14(a) shows the frequency characteristics of the insulation between the first element 41 and the third element 45, FIG. 14(b) shows the frequency characteristics of the VSWR of the first element 41, and FIG. 14(c) shows Frequency characteristics of the VSWR of the third element 45 . Referring to these figures, in the design frequency band of 814MHz to 894MHz, good insulation characteristics of about -14db or more can be obtained for the insulation. In addition, in the design frequency band of 814MHz to 894MHz, the VSWR characteristic of the first element 41 is within about 2.8 and is set to resonate at about 855MHz, and the VSWR characteristic of the third element 45 is within about 4.1 and is set to be within about 4.1. VSWR characteristics of 845MHz resonance.

Further, Fig. 15(a) shows the frequency characteristic of the insulation between the first element 41 and the fourth element 46, Fig. 15(b) shows the frequency characteristic of the VSWR of the first element 41, and Fig. 15(c) shows The frequency characteristics of the VSWR of the fourth element 46 are shown. Referring to these figures, in the design frequency band of 814 MHz to 894 MHz, good insulation characteristics of about -17 db or higher can be obtained for the insulation. In addition, in the design frequency band of 814 MHz to 894 MHz, the VSWR characteristic of the first element 41 is within approximately 3.0 and is set to resonate at around 850 MHz, and the VSWR characteristic of the fourth element 46 is within approximately 4.5 and is set to be within VSWR characteristics around 845MHz resonance.

In this way, in the antenna device 4 of the fourth embodiment, the first substrate 40 having a narrow width, and the surfaces and back surfaces of the second substrate 44 and the third substrate 47 substantially perpendicular to the first substrate 40 are respectively formed with the first substrate 40 . The first element 41, the second element 42, the third element 45, and the fourth element 46 do not substantially overlap each other by bending the shapes of the first element 41 to the fourth element 46 into an inverted "く" shape, and the The angle between the pattern of the first power supply matching part 41b and the pattern of the second power feeding matching part 42b and the angle between the pattern of the third power feeding matching part 49a and the pattern of the fourth power feeding matching part 49b are set to about 90°, so it can be considered that In the design frequency band described above, sufficient insulation characteristics and VSWR characteristics required for operation can be obtained.

Next, FIG. 16 shows the configuration of an antenna device according to a fifth embodiment of the present invention. FIG. 16 is a diagram showing the structure of the surface of the antenna device 5 of the fifth embodiment.

The antenna device 5 of the fifth embodiment is provided as a MIMO-compatible antenna device and includes two elements. As shown in FIG. 16, the antenna device 5 of the fifth embodiment has two elements, but unlike the two elements of the antenna device 1 of the first embodiment, the two elements are set in a structure that does not intersect, and other structures are set It has the same structure as that of the antenna device 1 of the first embodiment. Here, the description of the two elements of the antenna device 5 of the fifth embodiment will be mainly performed, and the description of the common configuration will be largely omitted. In the antenna device 5 of the fifth embodiment, the pattern of the first element 51 is formed on the front surface of the substrate 50 , and the pattern of the second element 52 is formed on the back surface of the substrate 50 . The first element 51 and the second element 52 are formed in the same shape, and are formed so that the substantially central portion is bent in an inverted "く" shape without overlapping each other. The lower end of the first element 51 is connected to the first power supply matching part 51b, and the first shortening coil 51a is connected to the upper end. In addition, the lower end of the second element 52 is connected to the second power supply matching portion 52b, and the second shortening coil 52a is connected to the upper end. The pattern of the first power supply matching portion 51b and the pattern of the second power supply matching portion 52b are rotated clockwise by about 45° with respect to the substrate 50, and the pattern of the second power supply matching portion 52b is opposite to the pattern of the first power supply matching portion 51b. Rotation angle θ5 formed. In addition, in the first power supply matching unit 51b and the second power supply matching unit 52b, for example, a π-type LC circuit is used, but illustrations of coils and capacitors are omitted, and only patterns of matching circuits are shown. Moreover, the notch part 50c inclined mutually is formed in the lower end of the board|substrate 50, respectively.

The length L8 is the physical length from the front end to the lower end of the first element 51 including the first shortening coil 51a or the second element 52 including the second shortening coil 52a, and the length L8 is set to about 0.333λ (about 119mm). The electrical length between the first element 51 including the first shortening coil 51a and the second element 52 including the second shortening coil 52a is approximately λ/2. In addition, the length L9 is the physical length from the lower end of the first element 51 or the second element 52 to the position where it is bent in an inverted "く" shape, and is set to about 0.162λ (about 58 mm). Further, the distance between the positions where the first element 51 and the second element 52 are bent in an inverted "く" shape is set to about 0.022λ (about 8 mm). Furthermore, the angle θ5 of the pattern of the second power supply matching portion 52b with respect to the pattern of the first power supply matching portion 51b is set to approximately 90°.

Here, the first element 51 and the second element 52 serve as a dipole antenna that feeds power (voltage feeds) at the ends of an electrical length of approximately λ/2. In the dipole antenna fed from the tip, the impedance of the feeding point becomes high, so the first element 51 is fed from a feeding line not shown by the first feeding matching part 51b to obtain matching, and the second feeding matching part 52b The second element 52 is supplied with power from a power supply line not shown in the figure to obtain matching.

Fig. 17(a) shows the frequency characteristics of the insulation between the first element 51 and the second element 52 of the antenna device 5 of the fifth embodiment set to the above dimensions, and Fig. 17(b) shows the first element The frequency characteristic of VSWR of 51, FIG. 17(c) shows the frequency characteristic of VSWR of the second element 52. Referring to these figures, in the designed frequency band of 814MHz to 894MHz, good insulation characteristics of about -10db or more can be obtained for the insulation. In addition, in the design frequency band of 814MHz to 894MHz, the VSWR characteristic of the first element 51 is within approximately 2.3 and is set to resonate at approximately 830MHz, and the VSWR characteristic of the second element 52 is within approximately 2.2 and is set to be within approximately 2.2. VSWR characteristics of 830MHz resonance. In this way, in the antenna device 5 of the fifth embodiment, the first element 51 and the second element 52 are respectively formed on the front surface and the back surface of the narrow substrate 50 so that they do not cross each other and do not overlap each other. The element 52 is formed to be bent in an inverted "く" shape at approximately the central part, and the angle between the pattern of the first power supply matching part 51b and the pattern of the second power supply matching part 52b is set to about 90°. Therefore, in the above-mentioned design frequency band Sufficient insulation characteristics and VSWR characteristics required for operation can be obtained.

Next, in order to better understand the antenna device according to the present invention, the antenna devices according to the first reference example to the fourth reference example of the present invention will be described. FIG. 18 shows the configuration of the antenna device 6 of the first reference example.

The antenna device 6 of the first reference example shown in FIG. 18 has two elements of the same shape, but unlike the two elements of the antenna device 1 of the first embodiment, the bending of the two elements is in an inverted "く" shape. The location is different. However, other configurations are common to those of the antenna device 1 of the first embodiment. Here, the description of the two elements of the antenna device 6 of the first reference example will be mainly given, and the description of the common configuration will be omitted. In the antenna device 6 of the first reference example, the pattern of the first element 61 is formed on the front surface of the substrate 60 , and the pattern of the second element 62 is formed on the back surface of the substrate 60 . The first element 61 and the second element 62 are set to have the same shape and are bent into an inverted "く" shape, and the bent position is set to the lower part, and the first element 61 and the second element 62 intersect the substrate 60 at the upper part, But except for the intersecting parts, the two elements are formed without overlapping. The lower end of the first element 61 is connected to the first power supply matching portion 61b, and the upper end is connected to the first shortening coil 61a. In addition, the lower end of the second element 62 is connected to the second power supply matching portion 62b, and the second shortening coil 62a is connected to the upper end. The pattern of the first power supply matching portion 61b and the pattern of the second power supply matching portion 62b are rotated clockwise by about 45° with respect to the substrate 60, and the pattern of the second power supply matching portion 62b is opposite to the pattern of the first power supply matching portion 61b. Formed by rotation angle θ6. In addition, in the 1st power supply matching part 61b and the 2nd power supply matching part 62b, only the pattern of a matching circuit is shown.

The length L10 is the physical length from the front end to the lower end of the first element 61 including the first shortening coil 61a or the second element 62 including the second shortening coil 62a, and the length L10 is set to about 0.333λ (about 119mm). The electrical length of the first element 61 including the first shortening coil 61a and the second element 62 including the second shortening coil 62a is approximately λ/2. In addition, the length L11 is the physical length from the lower end of the first element 61 or the second element 62 to the position where it is bent in an inverted "く" shape, and is set to about 0.094λ (about 33.5mm). Further, the distance between the positions where the first element 61 and the second element 62 are bent in an inverted "く" shape is set to about 0.022λ (about 8 mm). Furthermore, the angle θ6 of the pattern of the second power supply matching portion 62b with respect to the pattern of the first power supply matching portion 61b is set to approximately 90°.

Fig. 19(a) shows the frequency characteristic of the insulation between the first element 61 and the second element 62 of the antenna device 6 of the first reference example set to the above dimensions, and Fig. 19(b) shows the first element The frequency characteristic of VSWR of 61, FIG. 19(c) shows the frequency characteristic of VSWR of the second element 62. Referring to these figures, in the design frequency band of 814MHz to 894MHz, insulation can be obtained at about -7db or more. In addition, in the design frequency band of 814 MHz to 894 MHz, the VSWR characteristic of the first element 61 is within about 3.6 and is set to resonate at about 900 MHz, and the VSWR characteristic of the second element 62 is within about 2.8 and is set to be within about 2.8. 880MHz resonant VSWR characteristic. In this way, in the antenna device 6 of the first reference example, the first element 61 and the second element 62 of the same shape bent in an inverted "く" shape are formed on the front and back surfaces of the narrow substrate 60, respectively. 2. The lower part of the element 62 is bent in an inverted "く" shape, so it can be seen that sufficient insulation characteristics required for operation can be obtained in the above-mentioned designed frequency band.

In addition, Fig. 20 shows the configuration of an antenna device 6' of the second reference example.

The antenna device 6' of the second reference example shown in FIG. 20 has two elements of the same shape, but unlike the two elements of the antenna device 6 of the first reference example, only one of the two elements is bent in an opposite direction. The difference is that the position of the "く" character is set to the upper part. That is, in the antenna device 6' of the second reference example, the pattern of the first element 61' is formed on the surface of the substrate 60, and the pattern of the second element 62' is formed on the back surface of the substrate 60. About the 1st element 61' and the 2nd element 62', the approximate central part is bent in reverse "く" shape, and the bent position is set as the upper part, and the 1st element 61' and the 2nd element 62' are interposed between the board|substrate in the upper part. 60 crosses. The rest of the configuration is the same as that of the antenna device 6 of the first reference example, so description thereof will be omitted.

The length L12 is the physical length from the front end to the lower end of the first element 61' including the first shortening coil 61a or the second element 62' including the second shortening coil 62a, and the length L12 is set to about 0.333λ (about 119mm), At this time, the electrical length of the first element 61' including the first shortening coil 61a and the second element 62' including the second shortening coil 62a is approximately λ/2. In addition, the length L13 is the physical length from the lower end of the first element 61' or the second element 62' to the position where it is bent in an inverted "く" shape, and is set to about 0.262λ (about 93.5mm). Further, the distance between the positions where the first element 61' and the second element 62' are bent into an inverted "く" shape is set to about 0.022λ (about 8 mm).

Figure 21 (a) shows the frequency characteristics of the insulation between the first element 61' and the second element 62' of the antenna device 6' of the second reference example of the above-mentioned size, and Figure 21 (b) shows The frequency characteristic of VSWR of the first element 61 ′, and the frequency characteristic of VSWR of the second element 62 ′ are shown in FIG. 21( c ). Referring to these figures, in the design frequency band of 814MHz to 894MHz, insulation can be obtained at about -8db or more. In addition, in the design frequency band of 814MHz to 894MHz, the VSWR characteristic of the first element 61' is set to resonate at about 755MHz within about 3.0, and the VSWR characteristic of the second element 62' is set to be within about 2.7 and set to VSWR characteristics resonant at about 850MHz to 900MHz. In this way, in the antenna device 6' of the second reference example, the first element 61' and the second element 62' of the same shape bent in an inverted "く" shape are formed on the front and back surfaces of the narrow substrate 60, respectively. The element 61 ′ and the second element 62 ′ are bent in an inverted “く” shape at the upper part, so it can be seen that sufficient insulation characteristics required for operation can be obtained in the above-mentioned designed frequency band.

In this way, it can be seen that when the first element and the second element of the same shape that are bent into an inverted "く" shape are respectively formed on the front surface and the back surface of a narrow and elongated rectangular substrate, if the substantially central part is bent into If the "く" shape is reversed, good insulation properties can be obtained.

Furthermore, FIG. 22 shows the configuration of the antenna device 7 of the third reference example.

The antenna device 7 of the third reference example shown in FIG. 22 has two elements of the same shape, but unlike the substrate of the antenna device 1 of the first embodiment, a substrate with a widened lateral width is used, and the surface of the substrate and the substrate are connected to each other. Elements bent into a reverse "く" shape are respectively formed on the back side. Other configurations are the same as those of the antenna device 1 of the first embodiment. Here, explanations about common structures are omitted. In the antenna device 7 of the third reference example, the pattern of the first element 71 is formed on the surface of the substrate 70 having a wide lateral width, and the pattern of the second element 72 is formed on the back surface of the substrate 70 . The first element 71 and the second element 72 are set to have the same shape and the approximate central portion thereof is bent into an inverted "く" shape. The first element 71 and the second element 72 intersect the substrate 70 at the upper part, except for the intersecting part. Apart from parts, the two elements are formed without overlapping. The lower end of the first element 71 is connected to the first power supply matching part 71b, and the first shortening coil 71a is connected to the upper end. In addition, the lower end of the second element 72 is connected to the second power supply matching portion 72b, and the second shortening coil 72a is connected to the upper end. The pattern of the first power supply matching portion 71b and the pattern of the second power supply matching portion 72b are rotated clockwise by about 45° with respect to the substrate 70, and the pattern of the second power supply matching portion 72b is opposite to the pattern of the first power supply matching portion 71b. Formed by rotation angle θ7. In addition, in the 1st power supply matching part 71b and the 2nd power supply matching part 72b, only the pattern of a matching circuit is shown.

The length L14 is the physical length from the front end to the lower end of the first element 71 including the first shortening coil 71a or the second element 72 including the second shortening coil 72a, and the length L14 is set to about 0.333λ (about 119mm). The electrical length of the first element 71 including the first shortening coil 71a and the second element 72 including the second shortening coil 72a is approximately λ/2. In addition, the length L15 is the physical length from the lower end of the first element 71 or the second element 72 to the position where it is bent in an inverted "く" shape, and is set to about 0.162λ (about 58 mm). Further, the length L16 is the distance between the positions where the first element 71 and the second element 72 are bent into an inverted "く" shape, and is set to about 0.112λ (about 40 mm). Furthermore, the angle θ7 of the second power supply matching portion 72b with respect to the first power supply matching portion 71b is set to approximately 90°.

Fig. 23(a) shows the frequency characteristic of the insulation between the first element 71 and the second element 72 of the antenna device 7 of the third reference example set to the above-mentioned dimensions, and Fig. 23(b) shows the first element The frequency characteristic of VSWR of 71, FIG. 23(c) shows the frequency characteristic of VSWR of the second element 72. Referring to these figures, in the design frequency band of 814 MHz to 894 MHz, good insulation characteristics of about -12 db or higher can be obtained for the insulation. In addition, in the design frequency band of 814MHz to 894MHz, the VSWR characteristic of the first element 71 is within approximately 2.0 and is set to resonate at approximately 825MHz, and the VSWR characteristic of the second element 72 is within approximately 2.1 and is set to be within approximately 2.1. VSWR characteristics of 830MHz resonance. Thus, in the antenna device 7 of the third reference example, in the first element 71 and the second element 72 of the same shape whose front and back surfaces of the wide substrate 70 are bent into an inverted "く" shape, the widened In this way, there are positional intervals bent into an inverted "く" shape, so sufficient insulation characteristics required for operation can be obtained in the above-mentioned designed frequency band. However, the area of the substrate 70 becomes large, making miniaturization difficult.

Furthermore, FIG. 24 shows the configuration of the antenna device 8 of the fourth reference example.

The antenna device 8 of the fourth reference example shown in FIG. 24 is equipped with two elements of the same shape, and adopts a substrate whose lateral width is further widened from that of the antenna device 7 of the third reference example. Elements bent into a reverse "く" shape are respectively formed on the back side. Other configurations are the same as those of the antenna device 7 of the third reference example. Here, explanations about common structures are omitted. In the antenna device 8 of the fourth reference example, the pattern of the first element 81 is formed on the surface of the substrate 80 having a wider width, and the pattern of the second element 82 is formed on the back surface of the substrate 80 . The first element 81 and the second element 82 are set to have the same shape and their roughly central portion is bent into an inverted "く" shape. The first element 81 and the second element 82 intersect the substrate 80 at the upper part, except for the intersecting part. Apart from parts, the two elements are formed without overlapping. The lower end of the first element 81 is connected to the first power supply matching portion 81b, and the upper end is connected to the first shortening coil 81a. In addition, the lower end of the second element 82 is connected to the second power supply matching portion 82b, and the second shortening coil 82a is connected to the upper end. The pattern of the first power supply matching portion 81b and the pattern of the second power supply matching portion 82b are rotated clockwise by about 45° with respect to the substrate 80, and the pattern of the second power supply matching portion 82b is opposite to the pattern of the first power supply matching portion 81b. Formed by rotation angle θ8. In addition, in the 1st power supply matching part 81b and the 2nd power supply matching part 82b, only the pattern of a matching circuit is shown.

The length L17 is the physical length from the front end to the lower end of the first element 81 including the first shortening coil 81a or the second element 82 including the second shortening coil 82a, and the length L17 is set to about 0.333λ (about 119mm). The electrical length of the first element 81 including the first shortening coil 81a and the second element 82 including the second shortening coil 82a is approximately λ/2. In addition, the length L18 is the physical length from the lower end of the first element 81 or the second element 82 to the position where it is bent in an inverted "く" shape, and is set to about 0.162λ (about 58mm). Further, the length L19 is set to about 0.196λ (about 70 mm) as the distance between the position where the first element 81 and the second element 82 are bent in an inverted "く" shape. Furthermore, the angle θ8 of the second power supply matching portion 82b with respect to the first power supply matching portion 81b is set to approximately 90°.

Fig. 25(a) shows the frequency characteristics of the insulation between the first element 81 and the second element 82 of the antenna device 8 of the fourth reference example having the above-mentioned dimensions, and Fig. 25(b) shows the first element The frequency characteristic of VSWR of 81, FIG. 25(c) shows the frequency characteristic of VSWR of the second element 82. Referring to these figures, in the design frequency band of 814 MHz to 894 MHz, good insulation characteristics of about -13 db or higher can be obtained for the insulation. In addition, in the design frequency band of 814MHz to 894MHz, the VSWR characteristic of the first element 71 is within about 2.4 and is set to resonate at about 825MHz, and the VSWR characteristic of the second element 82 is within about 2.6 and is set to be within about 2.6. 820MHz resonant VSWR characteristic. In this way, in the antenna device 8 of the fourth reference example, in the first element 81 and the second element 82 of the same shape, the front and back of the substrate 80 having a wider width are bent in an inverted "く" shape, further expansion can be achieved. In the wide form, the positional intervals bent in an inverted "く" shape are formed, so that sufficient insulation characteristics required for operation can be obtained in the above-mentioned design frequency band. However, the area of the substrate 80 is further increased, and miniaturization becomes more difficult.

Thus, it can be seen that as the width of the substrate on which the first element and the second element curved in reverse "く" shapes are respectively formed on the front and the back is increased, the insulation characteristics become better, but the area of the substrate increases and the miniaturization becomes difficult. Compared with the conventional antenna device, the antenna device of the present invention, which can obtain good insulation characteristics even if the width of the substrate is narrowed and downsized, has a special function and effect.

Next, FIG. 26 to FIG. 28 show the configuration of an antenna device according to a sixth embodiment of the present invention. Fig. 26 is a perspective view showing the structure of the antenna device 9 of the sixth embodiment, Fig. 27 is an exploded perspective view viewed from the front side of the structure of the antenna device 9 of the sixth embodiment, and Fig. 28 is an exploded perspective view of the antenna device 9 from the sixth embodiment The exploded perspective view of the structure of 9 viewed from the back side.

As shown in these figures, the antenna device 9 of the sixth embodiment is installed inside a frame body 90 composed of a cover 91 having a U-shaped cross section and a base 92 fitted to close the open surface of the cover 91. Any one of the antenna devices 1 to 3 and 5 of the first to third embodiments and the fifth embodiment described above is accommodated. In FIG. 27 and FIG. 28, as an example, the structure in which the antenna device 1 of the first embodiment is accommodated in the housing 90 is shown, and the pattern of the first element 11 and the first feeding matching part 11b is formed on the surface. 1. In the substrate 10 with the pattern of the second element 12 and the second power supply matching part 12b formed on the back surface, the coaxial cable 93a connected to the first power supply matching part 11b is led out and connected to the second power supply matching part 12b A coaxial cable 93b is led out. The coaxial cable 93 a and the coaxial cable 93 b are led out substantially perpendicular to each other at the lead-out portion, and are led out so as to be partially fitted into the notch portion 10 c of the substrate 10 .

A spirally grooved circular boss 92a is protrudingly formed in the approximate center of the inner surface side of the base 92, and plate-shaped square bosses 92b are formed opposite to each other in the longitudinal direction on both sides of the upper part, and formed at the lower end. There is a bottom 92c. By fitting the round bosses 92a of the base 92 into the round holes 10a of the base 10, and fitting the pair of opposite bosses 92b of the base 92 into the pair of opposite holes 10b formed in the base 10, the base 10 is positioned and fastened to the base. 92. Moreover, 92 d of joint parts which consist of the step part lowered by one step on the outer surface side of the base 92 are formed in each of 3 on both side edges.

Plate-shaped convex ribs 91c are formed in the lateral direction on the inner surfaces of the two side parts 91b slightly higher than the central part of the "U"-shaped cover 91 in cross-section, and thin ribs 91c are formed on the inner surfaces of the upper part. Plate-shaped convex rib 91d. In addition, three low-height pressing ribs 91e formed in a U-shape are formed on the inner surface at predetermined intervals, and a bottom portion 91a is formed at the lower end. Furthermore, three connecting pieces 91f each having a wedge-shaped cross section are formed on both side portions 91b so as to protrude inward from the opening surface of the cover 91 . A total of six coupling pieces 91f are formed corresponding to the formation positions of a total of six coupling parts 92d formed on the chassis 92 .

When assembling to the antenna device 9 of the sixth embodiment shown in FIG. 26 , the substrate 10 is fastened to the base 92 as described above. Next, when the substrate 10 is inserted into the inside from the open surface of the cover 91, three U-shaped pressing ribs 91e are crimped to both side edges of the substrate 10, and a pair of convex ribs 91c are embedded in the substrate. The pair of first grooves 10d of 10 and further, the convex ribs 91d are fitted into the second grooves 10e of the substrate 10 , and the substrate 10 is positioned and held in the cover 91 . Then, when the base 92 is pressed into the cover 91 so as to close the open surface of the cover 91 , the six connecting pieces 91 f of the cover 91 are respectively connected to the six connecting parts 92 d of the base 92 . At this time, a notch is formed in the bottom portion 91a of the cover 91, and the bottom plate 92c of the chassis 92 is fitted into the notch. In the bottom 91a and the notch, two semicircular recesses are formed side by side to face each other, and the coaxial cable 93a and the coaxial cable 93b are led out from circular holes formed by the semicircular recesses. Thus, it is possible to assemble the antenna device 9 of the sixth embodiment in which the open surface of the cover 91 is closed by the base 92 .

In addition, the cover 91 and the base 92 are made of synthetic resin, and the housing 90 is transparent to radio waves. In addition, when housing the antenna devices 2 , 3 , and 5 of the second, third, and fifth embodiments in the housing 90 , it is only necessary to form circular holes and square holes at predetermined positions on the substrate. When the pattern of the element formed on the substrate is cut when forming the circular hole or the square hole on the substrate, a pattern is formed around the cut circular hole or square hole to prevent cutting.

Industrial availability

The dimensions described above in the antenna devices according to the embodiments of the present invention are dimensions as examples, and are not limited thereto. In addition, the dimensions shown in units of [mm] are the dimensions when the design frequency band is set to 814 MHz to 894 MHz, and if the design frequency band is different, it is legally changed according to the frequency band.

In the antenna device of the embodiment of the present invention described above, in the antenna device of the embodiment in which the first element and the second element are bent in the reverse "く" shape, instead of being bent in the reverse "く" shape, , may be bent into a "く" shape, and may be bent so that the distance between the first element and the second element becomes larger in the approximate center. In addition, in the antenna device of the embodiment in which the pattern of the first feeding matching part and the pattern of the second feeding matching part are rotated with respect to the substrate, the angle of the pattern of the second feeding matching part with respect to the pattern of the first feeding matching part It is set at about 90°, but it is not limited thereto, and if it is set at about 90°±about 30°, the same insulation characteristics and VSWR characteristics can be obtained.

In addition, in the antenna device of the fourth embodiment described above, the first substrate, the second substrate, and the third substrate are used, but it is also possible to prepare a first element and a second element formed on the front surface and the back surface, respectively. A substrate, and a second substrate on which the third element and the fourth element are respectively formed on the front and rear surfaces are formed by combining the first substrate and the second substrate so that the cross section becomes cross-shaped. In addition, the pattern of the second power supply matching part or the fourth power feeding matching part may be formed without rotating the pattern of the first power feeding matching part or the third power feeding matching part.

Claims (7)

1. An antenna device, characterized in that, possesses: Substrates in the shape of an elongated rectangle with narrowed width; a pattern of the first element formed on the surface of the substrate; a pattern of a second element having substantially the same shape as the first element formed on the back surface of the substrate; the pattern of the first power supply matching part formed on the lower part of the substrate and connected to the lower end of the first element; and the pattern of the second power supply matching part formed on the lower part of the substrate and connected to the lower end of the second element, The substantially central portions of the first element and the second element are bent so that the distance between the first element and the second element increases substantially at the central portion. 2. An antenna device, characterized in that, possesses: Substrates in the shape of an elongated rectangle with narrowed width; a pattern of the first element formed on the surface of the substrate; a pattern of a second element having substantially the same shape as the first element formed on the back surface of the substrate; the pattern of the first power supply matching part formed on the lower part of the substrate and connected to the lower end of the first element; and the pattern of the second power supply matching part formed on the lower part of the substrate and connected to the lower end of the second element, The pattern of the first power supply matching part and the pattern of the second power supply matching part are rotated by a predetermined angle with respect to the substrate, and the pattern of the second power supply matching part is relative to the pattern of the first power supply matching part. The angle is set to about 90° ± about 30°. 3. An antenna device, characterized in that, possesses: Substrates in the shape of an elongated rectangle with narrowed width; a pattern of the first element formed on the surface of the substrate; a pattern of a second element having substantially the same shape as the first element formed on the back surface of the substrate; the pattern of the first power supply matching part formed on the lower part of the substrate and connected to the lower end of the first element; and the pattern of the second power supply matching part formed on the lower part of the substrate and connected to the lower end of the second element, bending substantially central portions of the first element and the second element so that a distance between the first element and the second element becomes larger approximately at the central portion, and The pattern of the first power supply matching part and the pattern of the second power supply matching part are rotated by a predetermined angle with respect to the substrate, and the pattern of the second power supply matching part is relative to the pattern of the first power supply matching part. The angle is set to about 90° ± about 30°. 4. An antenna device, characterized in that, One of the antenna devices according to claims 1 to 3 is housed in a cover having a U-shaped cross section, and a flat base is fitted to the open surface of the cover to be closed. 5. An antenna device comprising an elongated rectangular-shaped first substrate with a narrowed width, and a second substrate arranged perpendicularly to the first substrate in a cross-section, the The antenna device is characterized in that On the surface of the first substrate, the pattern of the first element and the pattern of the first power supply matching part connected to the lower end of the first element are formed, On the back surface of the first substrate, the pattern of the second element and the pattern of the second power supply matching part connected to the lower end of the second element are formed, On the surface of the second substrate, the pattern of the third element and the pattern of the third power supply matching part connected to the lower end of the third element are formed, On the back surface of the second substrate, the pattern of the fourth element and the pattern of the fourth power supply matching part connected to the lower end of the fourth element are formed, The first member to the fourth member are provided in substantially the same shape, and the substantially central portions of the first member and the second member are bent so that the first member and the second member The distance between the third element and the fourth element is bent substantially at the center, and the distance between the third element and the fourth element becomes large at the center. 6. The antenna device according to claim 5, characterized in that, The pattern of the first power supply matching part and the pattern of the second power supply matching part are rotated by a predetermined angle with respect to the first substrate, and the pattern of the second power supply matching part is relative to the first power supply matching part. The angle of the pattern is set to about 90°±about 30°, and the pattern of the third power supply matching part and the pattern of the fourth power supply matching part are formed by rotating a predetermined angle with respect to the second substrate, the An angle of the pattern of the fourth power supply matching portion with respect to the pattern of the third power supply matching portion is set to be about 90°±about 30°. 7. The antenna device according to claim 5 or 6, characterized in that, The second substrate A and the second substrate b obtained by roughly cutting the second substrate in half are arranged laterally on both sides of the first substrate arranged in the vertical direction, so that the second substrate A and the second The substrate b is assembled so as to sandwich the first substrate, so that the first substrate and the second substrate are arranged in a cross-shaped cross section.