JP2013239929A - Antenna device and spacer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an antenna device which can be miniaturized without affecting antenna characteristics.SOLUTION: An antenna device 10 includes a planar antenna 100. In the planar antenna 100, an opening 130 is formed through which a coaxial cable 150 extending from an antenna pattern formed on a front surface of the planar antenna 100 is pulled out to the rear surface side of the planar antenna 100.

Description

  The present invention relates to an antenna device and a spacer.

  In recent years, with the expansion of wireless communication applications, antennas that operate in various frequency bands have been demanded as in-vehicle antennas mounted on automobiles. For example, as a vehicle-mounted antenna, terrestrial digital broadcasting such as FM / AM broadcasting, DAB (Digital Audio Broadcast), 3G (3rd Generation: third generation mobile phone), LTE (Long Term Evolution), GPS (Global Positioning System: There is a need for antennas that operate in frequency bands such as the Global Positioning System, VICS (registered trademark) (Vehicle Information and Communication System), and ETC (Electronic Toll Collection). .

  Some of the in-vehicle antennas typified by these can be installed in the car, or can be attached to the windshield or rear glass. Many can be attached. However, when the size of the antenna device attached to the outside of the body becomes large, there arises a problem that the design is damaged or the running performance is affected. Therefore, in order to avoid such a problem, an antenna device in consideration of downsizing has been conventionally devised.

  For example, the following Patent Document 1 discloses an antenna device that is used as an antenna for ETC having a resonance frequency of 5.8 GHz, and each of which is an antenna element in which a radiating conductor and a grounding conductor each made of a metal plate are arranged in parallel. An antenna device having the following is disclosed. In this antenna apparatus, the radiation conductor and the ground conductor are overlapped with each other in order to reduce the size of the antenna apparatus.

JP 2006-310950 A (released on November 9, 2006)

  However, the antenna device of Patent Document 1 has a problem that it is difficult to reduce the size including the power feeding cable. This is because, in the antenna device of Patent Document 1, the feeding cable is drawn out to the side of the antenna element (in a direction parallel to the surface of the antenna element). In particular, in the antenna device of Patent Document 1, when viewed from above, the feeding cable extends so as to gradually move away from the main body of the antenna device.

  For this reason, the antenna device of Patent Document 1 requires an installation space for the coaxial cable outside the antenna device body, and thus does not contribute to substantial downsizing. In the antenna device of Patent Document 1, it is conceivable to change the design so that the coaxial cable is placed inside the main body by bending the coaxial cable or the like, but naturally the size of the antenna device main body is increased.

  Further, in the antenna device of Patent Document 1, since the coaxial cable is connected to the surface of the antenna element and to the edge portion, the thickness corresponding to the diameter of the coaxial cable is required at least to the edge portion of the antenna element, and the thickness is reduced. It is also difficult to do. Further, in the antenna device of Patent Document 1, an opening for drawing the coaxial cable out of the main body is formed in the radome, which also affects the design.

  As a further problem, in the antenna device of Patent Document 1, the feeding point cannot be provided at a place other than the end of the antenna element. In the antenna device of Patent Document 1, since the coaxial cable is pulled out to the side of the antenna element, when the feeding point is provided at a place other than the end of the antenna element, the coaxial cable extends along the surface of the antenna element. This is because the stretched portion becomes longer, and parasitic resistance, parasitic capacitance, or parasitic inductance is generated between the coaxial cable and the antenna element, which influences the antenna characteristics. Due to such restrictions on the position of the feeding point, the antenna device of Patent Document 1 has a low degree of design freedom and cannot flexibly meet various specifications requirements.

  As described above, the conventional antenna device cannot be reduced in size and thickness without affecting the antenna characteristics. The present invention has been made in view of the above problems, and it is an object of the present invention to provide an antenna device that can be miniaturized without affecting antenna characteristics.

  In order to solve the above problems, an antenna device according to the present invention includes a planar antenna, and a coaxial cable extending from an antenna pattern formed on the surface of the planar antenna is connected to the planar antenna on the back side of the planar antenna. An opening for pulling it out is formed.

  According to this antenna device, since it is not necessary to pull out the coaxial cable to the side of the planar antenna, that is, there is no need for a space for the coaxial cable to go to the side of the planar antenna, the size of the antenna device can be reduced. Can do. Further, since it is not necessary to form an opening for drawing the coaxial cable from the side of the planar antenna to the outside, the design is not affected.

  Further, according to this antenna device, the feeding point can be provided at a place other than the edge of the planar antenna. Even in this case, the coaxial cable can be connected to the planar antenna by providing the opening near the feeding point. The portion extending along the surface of the antenna can be almost eliminated, so that the antenna characteristics are not affected.

  That is, according to this antenna device, since there is no restriction on the position of the feeding point, the degree of freedom in design is high, and it is possible to flexibly respond to various requirements in the specification. In particular, since the feeding point can be provided in the vicinity of the central portion of the planar antenna, the size of the antenna device main body can be reduced, and the shape of the edge that cannot be realized by the conventional antenna device (for example, the thickness is the central portion). It is also possible to make the shape gradually thinner toward the edge.

  The antenna apparatus includes a plurality of stacked planar antennas, and a coaxial cable extending from an antenna pattern formed on the surface of the planar antenna is drawn out to the back side of the planar antenna for each of the planar antennas. It is preferable that an opening is formed.

  According to this configuration, it is possible to achieve the same effect as the antenna device while being able to operate in a plurality of frequency bands.

  In the antenna device, a first planar antenna for pulling out a coaxial cable extending from an antenna pattern formed on the surface of the planar antenna to the back surface side of the planar antenna is at least one planar antenna of the plurality of planar antennas. It is preferable that a second opening for drawing out a coaxial cable connected to another planar antenna disposed on the front surface side of the planar antenna to the rear surface side of the planar antenna is formed. .

  According to this configuration, the coaxial cable corresponding to the upper planar antenna can be drawn out to the back side of the lower planar antenna without bypassing the side of the lower planar antenna. This eliminates the need for providing a space for bypassing the upper planar antenna on the side of the lower planar antenna, thereby reducing the size of the antenna device body.

  In the antenna device, it is preferable that the second opening formed in the one planar antenna is formed at a position overlapping the opening formed in the other planar antenna.

  According to this configuration, the coaxial cable corresponding to the upper planar antenna can be drawn out substantially linearly to the back surface side of the lower planar antenna. Thereby, the influence on the antenna characteristic by a coaxial cable can be suppressed more.

  In the antenna device, at least one planar antenna of the plurality of planar antennas includes a coaxial cable extending from an antenna pattern formed on the surface of the planar antenna, and another disposed on the surface side of the planar antenna. It is preferable that an opening for pulling out the coaxial cable connected to the planar antenna to the back side of the planar antenna is formed.

  According to this configuration, in the lower planar antenna, the coaxial cable corresponding to the planar antenna and the coaxial cable corresponding to the upper planar antenna can be passed through one opening. The number of openings can be reduced, and the space of the planar antenna can be used effectively. Moreover, these coaxial cables can be pulled out in an orderly manner.

  In the antenna device, it is preferable that the opening formed in the one planar antenna has a larger size than the opening formed in the other planar antenna.

  According to this configuration, the opening of the upper planar antenna can be made smaller than the opening of the lower planar antenna. That is, the size of the opening of each layer can be minimized, and the space on each planar antenna can be used effectively.

  Even in this case, since the number of coaxial cables drawn from the openings of the upper planar antenna is smaller than the number of coaxial cables drawn from the openings of the lower planar antenna, stress is applied to the coaxial cables in each layer. The coaxial cable can be pulled out without giving.

  The antenna device further includes a spacer that is fitted into the opening and defines a distance from another planar antenna facing the planar antenna, wherein the spacer extends from the upper surface to the lower surface of the spacer. It is preferable that a through hole and a second through hole that penetrates the side surface of the spacer and communicates with the first through hole are formed.

  According to this configuration, the coaxial cable can be easily and reliably guided from the side of the spacer to the bottom. In particular, since the passage of the coaxial cable is limited within the cylindrical portion of the spacer, the coaxial cable can be reliably pulled out below the antenna device without protruding to the side of the opening. Thus, for example, even if the coaxial cable is bent, the coaxial cable does not contact the planar antenna and affect the antenna characteristics, or the planar antenna is not deformed by applying pressure.

  In addition, according to this configuration, the spacer functions as a spacer portion that defines the interval between the opposing planar antennas. Therefore, when the interval is desired to be an arbitrary interval, the height is set according to the interval. It is sufficient to use spacers that are used, and this can be easily realized.

  In the antenna device, the spacer can be connected to another spacer configured in the same manner as the spacer, and the spacer can be inserted into the first through hole formed in the other spacer. And inserting the insertion portion into the first through-hole formed in the other spacer so that the planar antenna in which the spacer is fitted is interposed between the other spacer. It is preferable to be able to be connected to the other spacer in the sandwiched state.

  According to this configuration, it is possible to construct a support column with a plurality of spacers connected to each other, and to reliably support a plurality of planar antennas stacked on each other with a predetermined interval by the support column. it can. Moreover, since the 1st through-hole penetrated to an up-down direction is formed in each spacer, the channel | path of a several coaxial cable can be ensured in the said support | pillar.

  In the antenna device, a side surface of the insertion portion of the spacer is formed in the other spacer when the insertion portion is inserted into the first through hole formed in the other spacer. It is preferable that a third through hole penetrating the side surface and communicating with the first through hole is formed at a position overlapping with the second through hole.

  According to this configuration, it is possible to easily and reliably connect the plurality of spacers, and even when the plurality of spacers are connected to each other in this manner, the spacer From the side, the corresponding coaxial cable can be guided to the inside (first through hole) of the spacer.

  In the antenna device, a side surface of the insertion portion of the spacer is formed in the other spacer when the insertion portion is inserted into the first through hole formed in the other spacer. It is preferable that the 2nd fitting part fitted to the said 1st fitting part is formed in the position facing the 1st fitting part which is present.

  According to this configuration, the plurality of spacers can be reliably fixed in a state of being connected to each other. Thereby, a some planar antenna can be more reliably supported by a some spacer.

  The spacer according to the present invention is a spacer that is fitted into an opening formed in the planar antenna and defines a distance between the planar antenna and another planar antenna, and the spacer is an upper surface of the spacer. A first through-hole extending from the bottom surface to the lower surface and a second through-hole penetrating the side surface of the spacer and communicating with the first through-hole are formed.

  According to this spacer, the coaxial cable can be guided easily and reliably from the side of the spacer downward. In particular, since the passage of the coaxial cable is restricted within the cylindrical portion of the spacer, the coaxial cable can be reliably pulled out below the antenna device without protruding to the side of the opening. Thus, for example, even if the coaxial cable is bent, the coaxial cable does not contact the planar antenna and affect the antenna characteristics, or the planar antenna is not deformed by applying pressure.

  In addition, according to this spacer, it functions as a spacer portion that defines the interval between the opposing planar antennas. Therefore, when the interval is desired to be an arbitrary interval, the spacer has a height dimension corresponding to the interval. Can be used, and this can be easily realized.

  ADVANTAGE OF THE INVENTION According to this invention, the antenna apparatus which can be reduced in size without affecting an antenna characteristic can be provided.

1 shows a configuration of an antenna device 10 according to a first embodiment. (A) is a top view showing composition of antenna device 10 concerning a 1st embodiment. FIG. 2B is a side view illustrating the configuration of the planar antenna 10 according to the first embodiment. The structure of the antenna device 10 which concerns on 2nd Embodiment is shown. (A) is a top view which shows the structure of the antenna apparatus 10 which concerns on 2nd Embodiment. (B) is a side view which shows the structure of the planar antenna 10 which concerns on 2nd Embodiment. The structure of the antenna device 10 which concerns on 3rd Embodiment is shown. (A) is a top view which shows the structure of the antenna apparatus 10 which concerns on 3rd Embodiment. (B) is a side view which shows the structure of the planar antenna 10 which concerns on 3rd Embodiment. The structure of the antenna device 10 which concerns on 4th Embodiment is shown. (A) is a top view which shows the structure of the antenna apparatus 10 which concerns on 4th Embodiment. (B) is a side view which shows the structure of the planar antenna 10 which concerns on 4th Embodiment. The structure of the spacer 200 which concerns on 4th Embodiment is shown. (A) is a top view which shows the structure of the spacer 200 which concerns on 4th Embodiment. (B) is a front view which shows the structure of the spacer 200 which concerns on 4th Embodiment. (C) is a side view which shows the structure of the spacer 200 which concerns on 4th Embodiment. The connection state of the two spacers 200 is shown. (A) shows the state in which the two spacers 200 are not connected to each other. (B) shows a state in which two spacers 200 are connected to each other.

  Embodiments of the present invention will be described below with reference to the drawings.

[First Embodiment]
First, a first embodiment of the present invention will be described with reference to FIG. FIG. 1 shows a configuration of an antenna device 10 according to the first embodiment. FIG. 1A is a plan view showing the configuration of the antenna device 10 according to the first embodiment. FIG.1 (b) is a side view which shows the structure of the planar antenna 10 which concerns on 1st Embodiment.

(Configuration of antenna device 10)
As shown in FIG. 1, the antenna device 10 of this embodiment includes one planar antenna 100 and one coaxial cable 150. In the present embodiment, only the planar antenna 100 and the coaxial cable 150 among the components of the antenna device 10 are shown and described for easy understanding, but actually, the antenna device 10 of the present embodiment. In addition to this, the circuit board, a main body cover (for example, radome), a pedestal, and the like may be included in other components conforming to the use thereof.

(Configuration of planar antenna 100)
As shown in FIG. 1, the planar antenna 100 is an inverted F-type antenna configured by laminating a conductor layer 120 on the surface of a substrate 110. In the present embodiment, an inverted F-type antenna is used as an example of a planar antenna, but other antennas (monopole antenna, loop antenna, etc.) may be used.

(Substrate 110)
A thin plate-like insulator is used for the substrate 110 and is a portion that is the basis of the planar antenna 100. In the present embodiment, a dielectric film such as a polyimide film is used as the insulator, but other insulators may be used. In the present embodiment, the substrate 110 has a rectangular shape, but may have other shapes.

(Conductor layer 120)
The conductor layer (antenna pattern) 120 uses a thin plate-like conductor, and includes a ground plane 122, a short-circuit portion 124, and a radiating element 126. In the present embodiment, a conductor foil (for example, a copper foil) is used as the conductor, but other conductors may be used.

  Each of the ground plane 122, the short circuit portion 124, and the radiating element 126 has an appropriate shape and arrangement for allowing the planar antenna 100 to operate well in its intended frequency band within a limited space. .

  For example, the ground plane 122 has a rectangular shape having a relatively large area. The radiating element 126 extends in a band shape, and its overall length is approximately ¼ wavelength of the center frequency of the frequency band in order to have a resonance point in the frequency band. In particular, the radiating element 126 of the present embodiment has a so-called meander shape in which the pattern is folded back multiple times in order to accommodate the installation space of the radiating element 126 in the substrate 110. In addition, the short circuit portion 124 is configured to short-circuit the ground plane 122 and the radiating element 126 in order to optimize the input impedance of the planar antenna 100 in order to achieve impedance matching.

(Feeding point 128)
An outer conductor of the coaxial cable 150 is connected to the ground plate 122 (for example, soldered). A point where the outer conductor of the coaxial cable 150 is connected to the ground plane 122 is referred to as a “feed point 128A”.

  The radiating element 126 is connected (for example, soldered) to the inner conductor of the coaxial cable 150. A point where the inner conductor of the coaxial cable 150 is connected in the radiating element 126 is referred to as a “feeding point 128B”. The feeding point 128A and the feeding point 128B are collectively referred to as “feeding point 128”.

(Opening 130)
A point to be noted in the planar antenna 100 of the present embodiment is that the coaxial cable 150 (first coaxial cable) extending from the feeding point 128 is pulled out to the back side of the planar antenna 100 in the vicinity of the feeding point 128. An opening 130 (first opening) is formed.

  Thereby, in the antenna device 10 of the present embodiment, as shown in FIG. 1, the coaxial cable 150 connected to the feeding point 128 is bent in an L shape downward in the vicinity of the feeding point 128, thereby The cable 150 can be pulled out to the back side (lower side) of the planar antenna 100 through the opening 130.

  That is, the antenna device 10 according to the present embodiment does not require the coaxial cable 150 to be pulled out to the side of the planar antenna 100, so that there is no need for a space for placing the coaxial cable 150 on the side of the planar antenna 100. Can be miniaturized. Moreover, since it is not necessary to form an opening for drawing the coaxial cable 150 from the side of the planar antenna 100 to the outside, the design is not affected.

  Further, in the antenna device 10 of the present embodiment, the feeding point 128 can be provided at a place other than the edge of the planar antenna 100 (for example, in the vicinity of the central portion). Since a portion extending along the surface of the antenna 100 hardly occurs, the influence of the coaxial cable 150 on the antenna characteristics can be suppressed.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 2 shows a configuration of the antenna device 10 according to the second embodiment. FIG. 2A is a plan view showing the configuration of the antenna device 10 according to the second embodiment. FIG. 2B is a side view showing the configuration of the planar antenna 10 according to the second embodiment.

  The antenna device 10 according to this embodiment is a so-called integrated antenna device including a plurality of planar antennas 100. Specifically, as shown in FIG. 4, the antenna device 10 of this embodiment includes three planar antennas 100 (planar antenna 100-1, planar antenna 100-2, planar antenna 100-3) in order from the top. The main surfaces of the planar antennas 100 are stacked on each other so that they are parallel to each other. Each planar antenna 100 has the same configuration as that of the planar antenna 100 shown in FIG. 1, but the target frequency bands are different from each other.

  Such an antenna device 10 can be used for a vehicle-mounted antenna device suitable for mounting on the roof of an automobile. In particular, as shown in FIG. 2, the antenna device 10 according to the present embodiment is reduced in size because each coaxial cable 150 is pulled out below the antenna device 10 without protruding from the outer peripheral edge of the substrate 110. Suitable for use in roof antennas that require design.

  For example, the first layer planar antenna 100-1 is used for 3G (3rd Generation) / LTE (Long Term Evolution), and the second layer planar antenna 100-2 is used for DAB (Digital Audio Broadcast). The third layer antenna 3 is used for GPS (Global Positioning System).

  Of course, the use of each planar antenna 100 is not limited to these. For example, each planar antenna 100 may be used for ITS (700 MHz), Wi-Fi (2.4 GHz, 5 GHz), and Bluetooth (registered trademark) (2.4 GHz). Naturally, the antenna device 10 is also suitable for use other than the vehicle-mounted antenna device (for example, a mobile phone, a smartphone, a tablet terminal, etc.).

  The points to be noted in the antenna device 10 of the present embodiment are as follows (1) to (4).

  (1) In each planar antenna 100, a feeding point 128 is provided at a place other than its edge.

  (2) In each planar antenna 100, an opening 130 is formed in the vicinity of the feeding point 128. In each planar antenna 100, the corresponding coaxial cable 150 is drawn out to the back side of the planar antenna 100 through the opening 130. That is, in any planar antenna 100, a portion where the coaxial cable 150 extends along the surface hardly occurs.

  For example, the opening antenna 130-1 is formed in the first-layer planar antenna 100-1, and the corresponding coaxial cable 150-1 is connected to the planar antenna 100-1 via the opening 130-1. It is pulled out to the back side.

  Moreover, the opening 130-2 is formed in the planar antenna 100-2 of the second layer, and the corresponding coaxial cable 150-2 is connected to the planar antenna 100-2 via the opening 130-2. It is pulled out to the back side.

  In addition, the opening 130-3 is formed in the third-layer planar antenna 100-3, and the corresponding coaxial cable 150-3 is connected to the planar antenna 100-3 via the opening 130-3. It is pulled out to the back side.

  (3) The lower opening 130 has a larger diameter than the upper opening 130. As a result, the coaxial cable 150 corresponding to the upper planar antenna 100 can be passed through the lower opening 130 together with the coaxial cable 150 corresponding to the lower planar antenna 100.

  For example, in the example shown in FIG. 2, the opening 130-2 in the second layer has a larger diameter than the opening 130-1 in the first layer, and the opening 130-3 in the third layer The diameter is larger than that of the two-layer opening 130-2.

  As a result, the coaxial cable 150-1 corresponding to the first-layer planar antenna 100-1 is connected to the first-layer opening 130-1, the second-layer opening 130-2, and the third-layer opening. It is possible to penetrate 130-3.

  Further, the coaxial cable 150-2 corresponding to the second-layer planar antenna 100-2 can be passed through the second-layer opening 130-2 and the third-layer opening 130-3. ing.

  (4) In each planar antenna 100, the position of the feeding point 128 (position on the plane) is substantially the same position as the position of the feeding point 128 (position on the plane) in the other planar antenna 100. Accordingly, in each planar antenna 100, the position of the opening 130 (position on the plane) is substantially the same position as the position (position on the plane) of the opening 130 in the other planar antenna 100.

  For example, as shown in FIG. 2A, when the antenna device 10 is viewed from above, the opening 130-1, the opening 130-2, and the opening 130-3 overlap each other.

  As a result, as shown in FIG. 2 (b), the coaxial cable 150-1 corresponding to the first-layer planar antenna 100-1 is connected to the first-layer opening 130-1 and the second-layer opening 130-. 2 and the other coaxial cable 150 so as to pass through the opening 130-3 of the third layer and the third layer.

  2B, the coaxial cable 150-2 corresponding to the planar antenna 100-2 of the second layer is connected to the opening 130-2 of the second layer and the opening 130 of the third layer. -3 and the other coaxial cable 150 so as to pass through -3.

  Thus, in the antenna device 10 of the present embodiment, the plurality of openings 130 corresponding to the plurality of planar antennas 100 overlap each other. Thereby, it is possible to draw out the plurality of coaxial cables 150 in a straight line downward in a bundled state. That is, since each coaxial cable 150 has almost no portion extending along the surface of the planar antenna 100, the influence of the coaxial cable 150 on the antenna characteristics can be suppressed.

[Third Embodiment]
Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 3 shows a configuration of the antenna device 10 according to the third embodiment. FIG. 3A is a plan view showing the configuration of the antenna device 10 according to the third embodiment. FIG. 3B is a side view showing the configuration of the planar antenna 10 according to the third embodiment.

  In the second embodiment, the configuration example of the antenna device 10 in the case where the positions of the plurality of openings 130 are set to the same position (position on the plane) has been described, but in the third embodiment, the plurality of openings 130 are arranged. A configuration example of the antenna device 10 when the positions are different from each other (position on the plane) will be described.

  The points to be noted in the antenna device 10 of the present embodiment are as follows (5) to (7).

  (5) In each planar antenna 100, the feeding point 128 is provided at a place other than the edge.

  (6) The positions (positions on the plane) of the plurality of feeding points 128 corresponding to the plurality of planar antennas 100 are different from each other. Accordingly, the positions (positions on the plane) of the plurality of first openings 130 corresponding to the plurality of planar antennas 100 are different from each other. That is, in the antenna device 10 of this embodiment, when the antenna device 10 is viewed from above, the plurality of first openings 130 do not overlap each other.

  For example, as shown in FIG. 3A, when the antenna device 10 is viewed from above, the first opening 130-1 in the first layer, the first opening 130-2B in the second layer, and The first openings 130-3C in the third layer do not overlap each other. For this reason, each coaxial cable 150 cannot be drawn out linearly downward only by these first openings.

  (7) Therefore, in the lower planar antenna 100, in addition to the first opening 130, the second opening for drawing out the coaxial cable 150 corresponding to the upper planar antenna 100 to the lower side of the planar antenna. 130 is formed at substantially the same position (position on the plane) as the upper opening 130.

  For example, in the example shown in FIG. 3, the second-layer planar antenna 100-2 has a second opening 130 for pulling down the coaxial cable 150-1 corresponding to the first-layer planar antenna 100-1. The opening 130-2A is formed at substantially the same position (position on the plane) as the opening 130-1 of the first layer.

  Further, the third layer planar antenna 100-3 has an opening 130-3A as a second opening 130 for pulling out the coaxial cable 150-1 corresponding to the first layer planar antenna 100-1. Is formed at substantially the same position (position on the plane) as the opening 130-1 of the first layer.

  Further, the third-layer planar antenna 100-3 has an opening 130-3B as a second opening 130 for drawing the coaxial cable 150-2 corresponding to the second-layer planar antenna 100-2 downward. Is formed at substantially the same position (position on the plane) as the opening 130-2B of the second layer.

  Accordingly, as shown in FIG. 3B, the coaxial cable 150-1 corresponding to the first-layer planar antenna 100-1 is connected to the first-layer opening 130-1 and the second-layer opening 130-. 2A and the third layer opening 130-3A can be drawn downward in a substantially straight line.

  Further, as shown in FIG. 3B, the coaxial cable 150-2 corresponding to the planar antenna 100-2 of the second layer is connected to the opening 130-2B of the second layer and the opening 130 of the third layer. -3B can be drawn downward substantially linearly so as to pass through.

  As described above, in the antenna device 10 of the present embodiment, the plurality of first openings 130 corresponding to the plurality of planar antennas 100 are formed at different positions from each other, but correspond to each first opening 130. The second opening 130 is formed in the lower planar antenna 100. Thereby, each coaxial cable 150 can be drawn out linearly downward. That is, since each coaxial cable 150 has almost no portion extending along the surface of the planar antenna 100, the influence of the coaxial cable 150 on the antenna characteristics can be suppressed.

[Fourth Embodiment]
Next, a fourth embodiment of the present invention will be described with reference to FIGS. FIG. 4 shows a configuration of the antenna device 10 according to the fourth embodiment. FIG. 4A is a plan view showing the configuration of the antenna device 10 according to the fourth embodiment. FIG. 4B is a side view showing the configuration of the planar antenna 10 according to the fourth embodiment.

  The antenna device 10 according to the fourth embodiment is different from the antenna device 10 according to the second embodiment (FIG. 2) in that it includes a plurality of spacers 200 corresponding to the plurality of planar antennas 100. Each spacer 200 defines an interval between the opposing planar antennas, and the coaxial cable 150 can be guided from the front surface of the planar antenna 100 to the back surface side. Therefore, each spacer 200 has a first through hole penetrating in the vertical direction from the upper surface to the lower surface, and a second through hole penetrating in the lateral direction from the side surface to the first through hole. Is formed.

  As shown in FIG. 4, each spacer 200 is fitted into the opening 130 of the corresponding planar antenna 100 from above, and from the side of the spacer 200, the second through hole and the first through hole. The corresponding coaxial cable 150 is passed through. Accordingly, each spacer 200 can easily and reliably guide the coaxial cable 150 from the front surface of the planar antenna 100 to the back surface side.

  Another spacer 200 can be inserted into the first through hole. Thereby, the plurality of spacers 200 can be connected to each other in the vertical direction. Further, in a state where the plurality of spacers 200 are connected to each other, the plurality of first through holes are connected to each other to form one through hole. Thereby, even if the plurality of spacers 200 are connected to each other, the coaxial cable 150 can be passed therethrough.

  Each spacer 200 is configured such that only the upper cylindrical portion 210 (see FIG. 5) is exposed to the surface side of the planar antenna 100 in a state where the spacer 200 is fitted in the opening 130. As shown in FIG. 4, the upper cylindrical portion 210 functions as a spacer portion that defines the interval between the planar antennas 100 when the plurality of planar antennas 100 are stacked on each other. Thereby, in the antenna apparatus 10 of this embodiment, the space | interval of the planar antennas 100 which oppose is predetermined.

(Configuration of spacer 200)
Here, with reference to FIG. 5 and FIG. 6, the structure of the spacer 200 which concerns on 4th Embodiment is demonstrated concretely.

  FIG. 5 shows a configuration of a spacer 200 according to the fourth embodiment. FIG. 5A is a plan view showing the configuration of the spacer 200 according to the fourth embodiment. FIG. 5B is a front view showing the configuration of the spacer 200 according to the fourth embodiment. FIG. 5C is a side view showing the configuration of the spacer 200 according to the fourth embodiment.

  FIG. 6 shows the connection state of the two spacers 200. FIG. 6A shows a state where the two spacers 200 are not connected to each other. FIG. 6B shows a state where the two spacers 200 are connected to each other.

(Spacer shape)
As shown in FIG. 5, the spacer 200 of this embodiment has a cylindrical shape. That is, in the spacer 200 of this embodiment, the cylinder part functions as the first through hole. Resin is used for the spacer 200, but an insulator other than this may be used, or a conductor such as metal may be used. In the latter case, the spacer 200 can function as the ground of the planar antenna 100 by grounding the spacer 200.

  The spacer 200 has an upper cylinder part 210 and a lower cylinder part 220. The lower cylinder part 220 is a part whose outer diameter is smaller than that of the upper cylinder part 210. The outer diameter of the lower cylindrical portion 220 is smaller than the diameter of the opening 130. Thereby, the lower cylinder part 220 can be inserted into the opening 130.

  On the other hand, the outer diameter of the upper cylinder part 210 is larger than the diameter of the opening part 130. Thereby, the upper cylinder part 210 does not enter the opening part 130 but is exposed to the surface side of the planar antenna 100, and can serve as a spacer as described above. For this reason, the height dimension of the upper cylinder part 210 is substantially equal to the prescribed value of the interval between the planar antennas 100.

(Spacer connection)
The outer diameter of the lower cylindrical portion 220 is smaller than the inner diameter of the cylindrical portion of the spacer 200 (that is, the diameter of the first through hole). Thereby, as shown in FIG. 6, the lower cylindrical portion 220 can be inserted into the cylindrical portion of another spacer 200. That is, the lower cylinder part 220 functions as an insertion part.

  When the spacer 200 is fitted in the opening 130, the lower cylindrical portion 210 is exposed on the back surface side of the planar antenna 100. For this reason, the spacer 200 can be connected to the other lower spacer 200 in a state where the spacer 200 is fitted in the opening 130. Thus, the spacer 200 can sandwich the planar antenna 100 together with the other spacers 200, and can reliably support the planar antenna 100.

  The plurality of spacers 200 included in the antenna device 10 all have the same configuration, and as a result, as shown in FIG. 4, the plurality of spacers 200 can be connected to each other. Each spacer 200 is fitted in the opening 130 of the corresponding planar antenna 100, so that the corresponding planar antenna 100 can be supported.

  Thereby, in the antenna device 10 of the present embodiment, as shown in FIG. 4, a plurality of planar antennas 100 are stacked on each other, and the spacing between the planar antennas 100 is a predetermined spacing. In this state, the plurality of planar antennas 100 can be supported by the plurality of spacers 200 as columns.

(Side opening)
In each spacer 200, a side opening 212 is formed on the outer peripheral surface of the upper cylindrical portion 210 (that is, the side surface of the upper cylindrical portion 210). The side opening 212 is for passing the coaxial cable 150 from the side of the spacer 200 into the cylindrical portion of the spacer 200. That is, in the spacer 200 of the present embodiment, the side opening 212 functions as the second through hole. Therefore, in each spacer 200, the side opening 212 is formed at a position facing the feeding point 128 when the spacer 200 is fitted into the opening 130.

  As a result, as shown in FIG. 4, the spacer 200 can pass the cable 150 extending from the feeding point 128 through the cylindrical portion of the spacer 200 while being fitted in the through hole 130.

  A side opening 222 (third through hole) is formed on the surface of the lower cylindrical portion 220 (that is, the side surface of the lower cylindrical portion 220). The spacer 200 is configured such that the side opening 222 of the spacer 200 overlaps the side opening 212 of the other spacer 200 when connected to the other spacer 200.

  As a result, as shown in FIG. 4, each spacer 200 has a cable 150 extending from a feeding point 128 positioned on the side of the spacer 200 with the other spacer 200 connected to the upper side. It is possible to pass through the tube part.

(Fixing mechanism)
As shown in FIG. 5, the lower cylindrical portion 220 of the spacer 200 is formed with a claw 224 that protrudes from the surface thereof. The claw 224 mainly functions as a rotation stopper and a stopper for the planar antenna 100.

  For example, as shown in FIG. 6, when the lower cylindrical portion 220 of one spacer 200 is inserted into the upper cylindrical portion 210 of another spacer 200, a claw 224 (first 2 fitting portion) is fitted into a claw receiver 214 (first fitting portion) formed at a position facing the upper cylindrical portion 210. As a result, the two spacers 200 are securely fixed in a state of being connected to each other, and do not easily come off or rotate.

  Thus, according to the antenna device 10 of the present embodiment, the path of each coaxial cable 150 is limited within the cylindrical portion of the spacer 200, so that each coaxial cable 150 does not protrude to the side of the opening 130, The antenna device 10 can be reliably pulled out below. Thereby, for example, even if the coaxial cable 150 is bent, the coaxial cable 150 is in contact with the planar antenna 100 and affects the antenna characteristics, or the planar antenna 100 is deformed by applying pressure. There is nothing.

  Further, according to the antenna device 10 of the present embodiment, the upper cylindrical portion 210 of the spacer 200 functions as a spacer portion that defines the interval between the opposing planar antennas 100. For this reason, when it is desired to set the interval to an arbitrary interval, the spacer 200 having the upper cylindrical portion 210 having a height dimension corresponding to the interval may be used, and this can be easily realized. It has become.

  Further, according to the antenna device 10 of the present embodiment, the opening 130 can be reinforced by providing the spacer 200. Thereby, the edge part of the opening part 130 does not deform | transform, when the coaxial cable 150 is pressed.

  Further, according to the antenna device 10 of the present embodiment, since the plurality of spacers 200 are connected, the plurality of spacers 200 function as pillars that support the plurality of planar antennas 100 inside the antenna device 10. The rigidity of the entire antenna device 10 can be increased.

  Furthermore, according to the antenna device 10 of the present embodiment, the plurality of spacers 200 can be securely fixed in a state of being connected to each other. As shown, they can be reliably supported in a state where they are stacked on each other.

[Supplementary explanation of the embodiment]
(About spacer shape)
In the antenna device 10 according to the fourth embodiment, the spacer 200 has a cylindrical shape. However, any shape other than the above (for example, a rectangular tube shape or the like) can be used as long as it can realize the same function as the above function. ).

  Further, in the antenna device 10 of the fourth embodiment, the fixing mechanism (claw 224 and claw receiver 214) provided in the spacer 200 has both functions of preventing rotation and retaining, but does not prevent rotation. It may have one of the functions of retaining and retaining. Further, the fixing mechanism may be realized by a configuration other than the configuration described in the fourth embodiment. For example, in the spacer 200, the same function as the above-described fixing mechanism can be realized by making the outer diameter of the lower cylindrical portion 220 and the inner diameter of the cylindrical portion substantially the same size.

  In addition, each spacer 200 demonstrated in 4th Embodiment can also be fitted in the opening part 130 from the back surface side of the planar antenna 100 by reversing up and down.

(How to fix spacer and flat antenna)
In the antenna device 10 according to the fourth embodiment, a configuration in which the planar antenna 100 is supported by the pair of spacers 200 sandwiching the planar antenna 100 is employed. However, the configuration is not limited to this, and a configuration in which the spacer 200 is fixed to the planar antenna 100 by a fixing tool such as a screw may be employed. Thereby, the spacer 200 is more reliably fixed to the planar antenna 100, that is, the planar antenna 100 can be reliably supported.

(About spacer reinforcement)
In the antenna device 10 according to the fourth embodiment, the cylindrical portion of each spacer 200 may be filled with a filler such as resin. Thereby, while being able to reinforce a spacer, the tolerance of a junction part to the tension of coaxial cable 150 can be improved.

(About the number of planar antennas)
In the antenna device 10 of each embodiment, the number of planar antennas 100 can be changed as appropriate. For example, in the antenna device 10 of the second to fourth embodiments, a configuration in which three planar antennas 100 are stacked on each other is adopted, but a configuration in which two planar antennas 100 are stacked on each other is employed. It is also possible to adopt a configuration in which four or more planar antennas 100 are stacked on each other.

(About the shape of the planar antenna)
In the antenna device 10 of each embodiment, the shape and size of the planar antenna 100 can be changed as appropriate. For example, the antenna device 10 of the second to fourth embodiments employs a configuration in which a plurality of planar antennas 100 having the same shape and size are stacked, but a plurality of planes having different shapes and sizes. It is also possible to adopt a configuration in which the antenna 100 is stacked.

  In the antenna device 10 of each embodiment, the shape and size of each part (the ground plane 122, the short circuit part 124, and the radiating element 126) of the planar antenna 100 can be changed as appropriate.

(About planar antenna placement)
In the antenna device 10 that employs a configuration in which a plurality of planar antennas 100 are stacked, a planar antenna that receives an electromagnetic wave with a stronger standard electric field strength is disposed below the planar antenna that receives an electromagnetic wave with a weaker standard electric field strength. It is preferable.

  For example, in the antenna device 10 shown in FIGS. 2 to 4, more coaxial cables 150 run near the lower planar antenna 100. For example, there is 1 in the first layer, 2 in the second layer, and 3 in the third layer. The greater the number of coaxial cables 150, the higher the possibility of being affected by noise. That is, the lower level planar antenna 100 is more likely to be affected by noise.

  Therefore, a planar antenna that receives an electromagnetic wave having a high standard electric field strength is arranged in a lower layer. Thereby, the influence of noise can be minimized in the antenna device 10 as a whole.

  For example, a planar antenna 100 that receives DAB waves and a planar antenna 100 that receives GPS waves will be described as examples.

  First, the standard electric field strength of the GPS wave is weaker than the standard electric field strength of the DAB wave, and is about −130 to −140 dBm. For this reason, the planar antenna 100 that receives GPS waves is likely to be affected by noise from the plurality of coaxial cables 150 that run in the vicinity.

  On the other hand, the standard electric field strength of DAB waves is stronger than the standard electric field strength of GPS waves, and is about -60 dBm. For this reason, the planar antenna 100 that receives DAB waves is unlikely to be affected by noise from the plurality of coaxial cables 150 that run in the vicinity.

  For this reason, the planar antenna 100 that receives a DAB wave with a high standard electric field strength is disposed below the flat antenna 100 that receives a GPS wave with a low standard electric field strength, so that reception failure occurs as a whole in the antenna device 10. The possibility can be minimized.

(About the position of the opening)
In the antenna device 10 of each embodiment, the position where the opening 130 is formed can be changed as appropriate. For example, in the antenna device 10 of the first to fourth embodiments, the opening 130 is formed at a position where the ground plate 122 is provided in the planar antenna 100, but the opening 130 is formed at a position other than this. May be.

(About the shape of the opening)
In the antenna device 10 of each embodiment, the shape and size of the opening 130 can be changed as appropriate. For example, in the antenna device 10 according to the first to fourth embodiments, a circular shape is adopted as the shape of the opening 130, but other shapes (rectangular shape, polygonal shape, elliptical shape, long hole shape, etc.) are used. It is also possible to adopt. In short, the shape and size of the opening 130 may be any shape and size as long as it can penetrate at least the required number of coaxial cables 150.

(About the configuration of the antenna device)
The antenna device 10 according to the fourth embodiment has a main body such as one or more planar antennas or a circuit board by further connecting one or more other spacers 200 to the upper side of the first layer spacer 200-1. It is possible to laminate other members such as a cover.

  Alternatively, if a protrusion having the same shape as that of the lower cylindrical portion 220 is provided, it is possible to directly connect another member to the upper side of the first layer spacer 200-1. .

  Further, the antenna device 10 shown in FIG. 4 further includes one or more planar antennas, a case, a pedestal, or the like by further connecting one or more other spacers 200 to the lower side of the third layer spacer 200-3. It is possible to laminate other members such as a circuit board.

  Alternatively, if an opening similar to that of the cylindrical portion of the spacer 200 is provided, another member can be directly connected to the lower side of the spacer 200-3 of the third layer.

[Additional Notes]
The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope shown in the claims. That is, embodiments obtained by combining technical means appropriately modified within the scope of the claims are also included in the technical scope of the present invention.

  The present invention can be suitably used as an antenna device mounted on a mobile body or a mobile terminal, or as a spacer mounted on such an antenna device. Examples of the moving body include an automobile, a railway vehicle, and a ship. Examples of mobile terminals include mobile phone terminals, smartphones, tablet terminals, and PDAs (Personal Digital Assistance).

DESCRIPTION OF SYMBOLS 10 Antenna apparatus 100 Planar antenna 110 Board | substrate 120 Conductor layer 122 Ground plane 124 Short circuit part 126 Radiation element 128 Feed point 130 Opening part (1st opening part, 2nd opening part)
150 Coaxial cable 200 Spacer 210 Upper cylindrical portion 212 Side opening (second through hole)
214 Claw receptacle (first fitting part)
220 Lower cylinder portion 222 Side opening (third through hole)
224 claw (second fitting part)

Claims (11)

With a planar antenna,
The planar antenna is provided with an opening for drawing out a coaxial cable extending from an antenna pattern formed on the surface of the planar antenna to the back side of the planar antenna. A plurality of stacked planar antennas,
Each of the plurality of planar antennas is formed with an opening for drawing out a coaxial cable extending from an antenna pattern formed on the surface of the planar antenna to the back side of the planar antenna. Item 2. The antenna device according to Item 1. In addition to the first opening for drawing out the coaxial cable extending from the antenna pattern formed on the surface of the planar antenna to the back side of the planar antenna, the planar antenna of at least one of the plurality of planar antennas The second opening for drawing out a coaxial cable connected to another planar antenna disposed on the front surface side of the planar antenna to the back surface side of the planar antenna is formed. The antenna device according to 1. The antenna device according to claim 3, wherein the second opening formed in the one planar antenna is formed at a position overlapping the opening formed in the other planar antenna. . At least one of the plurality of planar antennas is connected to another planar antenna disposed on the surface side of the planar antenna, together with a coaxial cable extending from an antenna pattern formed on the surface of the planar antenna. The antenna device according to claim 2, wherein an opening for drawing out the coaxial cable formed to the back surface side of the planar antenna is formed. The antenna device according to claim 5, wherein the opening formed in the one planar antenna has a size larger than the opening formed in the other planar antenna. A spacer that is fitted into the opening and defines a distance between the planar antenna and the other planar antenna;
The spacer is
A first through hole extending from the upper surface to the lower surface of the spacer;
The antenna device according to any one of claims 2 to 6, wherein a second through hole penetrating a side surface of the spacer and communicating with the first through hole is formed. The spacer is connectable with other spacers configured similarly to the spacer,
The spacer has an insertion part that can be inserted into the first through-hole formed in the other spacer, and the insertion part is formed in the other spacer. The antenna device according to claim 7, wherein the antenna device can be connected to the other spacer in a state where the planar antenna in which the spacer is fitted is sandwiched between the spacer and the other spacer. On the side surface of the insertion part of the spacer, the second part formed in the other spacer when the insertion part is inserted into the first through hole formed in the other spacer. The antenna device according to claim 8, wherein a third through hole that penetrates the side surface and communicates with the first through hole is formed at a position overlapping with the through hole. A first fitting formed in the other spacer when the insertion portion is inserted into the first through hole formed in the other spacer is formed on a side surface of the insertion portion of the spacer. 10. The antenna device according to claim 8, wherein a second fitting portion that fits with the first fitting portion is formed at a position facing the joint portion. A spacer that is fitted into an opening formed in a planar antenna and defines a distance between the planar antenna and another planar antenna,
The spacer is
A first through hole extending from the upper surface to the lower surface of the spacer;
The spacer is characterized in that a second through-hole is formed which penetrates the side surface of the spacer and communicates with the first through-hole.

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