JP2010062964A - Compound antenna system - Google Patents

Abstract

Provided is a composite antenna device capable of obtaining a stable gain characteristic with respect to an ETC antenna regardless of the distance between a built-in ETC antenna and a windshield.
A composite antenna device has a common ground plate with a notch formed therein, and convex portions are formed at both left and right ends of a first end side. On the common ground plate 110, the ETC antenna unit 120. A GPS antenna 131 and a VICS antenna 132 are arranged. By forming the notch 115 on the common ground plate 110, it is possible to obtain a stable gain characteristic for the ETC antenna 121 regardless of the distance between the ETC antenna 121 and the windshield 141.
[Selection] Figure 1

Description

  The present invention relates to an in-vehicle composite antenna device having two or more antennas on one ground plane.

  Recently, automobiles are equipped with multiple in-vehicle antennas such as GPS (Global Positioning System) antennas, mobile phone antennas, ETC (Automatic Toll Collection System) antennas, and VICS (Road Traffic Information Communication System) antennas. It has come to be. These antennas are usually installed and used on instrument panels (hereinafter referred to as instrument panels) in the passenger compartment, but as the number of antennas mounted on the vehicle increases in this way, the installation location of each antenna is increased. It is becoming difficult to secure. Moreover, when each is attached separately, it is unpreferable also on an external appearance.

Therefore, development of a composite antenna device in which a plurality of antennas are integrated to save space is underway. Patent Document 1 discloses a composite antenna device 900 in which an ETC antenna 901, a GPS antenna 902, and a VICS antenna 903 are integrated by sharing one ground plane 904. Here, the GPS ground plane 904 having the lowest frequency band is shared, and an ETC antenna 901 that is sub-assembled is arranged thereon.
JP 2004-56773 A

  However, the composite antenna device described in Patent Document 1 has a problem that the gain of the ETC antenna changes depending on the installation position. That is, when the composite antenna device described in Patent Document 1 is installed in or on the instrument panel, there is a problem that the gain of the ETC antenna changes depending on the distance between the ETC antenna and the windshield of the vehicle. In addition, the tendency of the gain change is not always constant, and there is a problem that, for example, as the ETC antenna is brought closer to the windshield, the gain is increased or decreased, and a stable gain characteristic cannot be obtained.

  Accordingly, the present invention has been made to solve the above problems, and provides a composite antenna device capable of obtaining a stable gain characteristic for an ETC antenna regardless of the distance between the built-in ETC antenna and the windshield. For the purpose.

  A first aspect of the composite antenna device of the present invention is a composite antenna device in which an ETC antenna and one or more other antennas are disposed on the same common ground plane and are installed in the vicinity of the indoor side of a vehicle windshield. The ETC antenna is disposed at a predetermined position on the common ground plane so as to be inclined in the traveling direction, and the common ground plane is cut to a predetermined depth at an end side on which the ETC antenna is inclined. A notch is formed.

  Another aspect of the composite antenna device of the present invention is characterized in that the cutout portion is cut out so as to be symmetrical with respect to the center line of the common ground plane passing through the center of the ETC antenna.

  Another aspect of the composite antenna device of the present invention is characterized in that the distance between the nearest edges between the ETC antenna and the notch is at least 1 / (2π) or more of the wavelength of the ETC antenna. To do.

  In another aspect of the composite antenna device of the present invention, the predetermined depth is such that the distance between the center of the ETC antenna and the edge of the notch closest to the ETC antenna is 1/2 of the wavelength of the ETC antenna. The size is shorter.

  In another aspect of the composite antenna device of the present invention, the notch is formed in a substantially rectangular shape so that the length of the end side closest to the ETC antenna is a predetermined length. .

  Another aspect of the composite antenna device of the present invention is characterized in that the notch is formed in a substantially trapezoidal shape so that the length of the end side closest to the ETC antenna is a predetermined length. .

  Another aspect of the composite antenna device of the present invention is characterized in that the predetermined length is equal to or longer than the wavelength of the ETC antenna.

  Another aspect of the composite antenna device of the present invention is a composite antenna device in which an ETC antenna and one or more other antennas are arranged on the same common ground plane and are installed in the vicinity of the vehicle windshield indoor side, The ETC antenna is disposed at a predetermined position on the common ground plane so as to be inclined in the traveling direction, and the common ground plane is substantially the same as the ETC antenna from a side edge on which the ETC antenna is inclined to a predetermined depth. A bent portion that is bent in parallel is formed.

  Another aspect of the composite antenna device of the present invention is characterized in that the distance between the closest edges between the ETC antenna and the bent portion is at least 1 / (2π) or more of the wavelength of the ETC antenna. .

  In another aspect of the composite antenna device of the present invention, the predetermined depth is such that the distance between the center of the ETC antenna and the edge of the bent portion closest to the ETC antenna is less than ½ of the wavelength of the ETC antenna. It is the size which becomes short.

  Another aspect of the composite antenna device of the present invention is characterized in that a GPS antenna is provided as the another antenna, and a ground plane of the GPS antenna is used as the shared ground plane.

  In another aspect of the composite antenna device of the present invention, the ETC antenna is a patch antenna.

  According to the present invention, by forming the common ground plane of the composite antenna device incorporating the ETC antenna into a predetermined shape, a stable gain characteristic can be obtained for the ETC antenna regardless of the distance between the ETC antenna and the windshield. A composite antenna device can be provided.

  A composite antenna device according to a preferred embodiment of the present invention will be described in detail with reference to the drawings. In addition, about each structure part which has the same function, the same code | symbol is attached | subjected and shown for simplification of illustration and description. The composite antenna device of the present invention has two or more antennas including an ETC antenna, and each antenna is arranged on a common ground plane. Hereinafter, as an example of the common ground plane, a ground plane of a GPS antenna whose use band is lower than ETC (long wavelength) is used.

(First embodiment)
A composite antenna device according to a first embodiment of the present invention is shown in FIGS. FIG. 1 is a perspective view of a composite antenna device 100 according to the present embodiment, and FIG. 2 is a plan view of the composite antenna device 100. The composite antenna device 100 has a structure in which one ground plane 110 is shared and an ETC antenna 121, a GPS antenna 131, and a VICS antenna 132 are arranged thereon. The ETC antenna 121 can be formed by a patch antenna. These antennas are covered and protected by a single radome 101. The antenna 132 is not limited to the VICS antenna, and may be an in-vehicle communication antenna, for example.

  The ETC antenna 121 is sub-assembled together with the ETC antenna circuit board 122 to constitute the ETC antenna unit 120. The GPS antenna 131 and the VICS antenna 132 are placed on the circuit board 133 to form a subassembly, which is disposed on the common ground plane 110.

  The ETC antenna unit 120 is installed at a predetermined angle with respect to the ground plane 110 so that good communication is possible when the roadside device of the ETC is in a predetermined angle range in front of the vehicle. Further, the ETC antenna 121 is disposed at a position that is symmetrical with respect to the center line of the common ground plane 110 passing through the center thereof. The composite antenna device 100 is installed in front of the passenger compartment, that is, in the vicinity of the windshield in the instrument panel so that it can communicate with the ETC roadside device in front of the vehicle. An installation example of the composite antenna device 100 is shown in FIG. FIG. 3 shows an example in which the composite antenna device 100 is installed in a vehicle 140. Here, the composite antenna device 100 is installed in the vicinity of the windshield 141 in the instrument panel 142, so that the ETC antenna 121 can perform good communication with the ETC roadside device 140.

  The main dimensions of the composite antenna device 100 are shown in the plan view of FIG. Here, since the ground plane of the GPS antenna 131 is the shared ground plane 110, the length of one side of the shared ground plane 110 is 90 mm. The ETC antenna unit 120 is disposed on the vehicle front side from the center of the common ground plate 110 and is located at the center of the common ground plate 110 in the left-right direction. The distance between the center of the ETC antenna 121 and the front side edge (hereinafter referred to as the first side edge) 111 of the common ground plate 110 is 26 mm as an example here.

  In the composite antenna device 100 of the present embodiment, a notch 115 is formed by cutting off a part of the common ground plate 110. The notch 115 is formed at the center in the left-right direction along the first end side 111, and the protrusions 116 are left at the left and right ends of the first end side 111. The bottom side of the notch 115 is indicated by reference numeral 115a. Hereinafter, the notch depth of the notch 115 (same as the protruding length of the protrusion 116) is D, and the width of the protrusion 116 is W. Thereby, the length (first length) of the first end 111 of the notch 115 becomes (90 mm−2 W). When the wavelength of the ETC antenna 121 is λ, the first length is preferably not less than the wavelength λ.

  Further, the installation position of the composite antenna device 100 shown in FIG. 3 in the vehicle 140 will be described in detail with reference to FIG. 4 shows the positional relationship between the ETC antenna unit 120 and the common ground plate 110 and the windshield 141, and shows an enlarged cross-sectional view taken along the line AA 'passing through the center of the ETC antenna unit 120 shown in FIG. Here, the distance between the center O of the ETC antenna 121 and the windshield 141 is L. Further, the reception angle received by the ETC antenna 121 from an ETC roadside device (not shown) is an angle inclined by α with respect to the perpendicular. Furthermore, it is assumed that the common ground plate 110 is disposed horizontally, and the windshield 141 is inclined by an angle β with respect to the horizontal direction (and the common ground plate 110).

  The distance between the center O of the ETC antenna 121 and the common ground plane 110 is H, and a point that is perpendicular to the common ground plane 110 from the center O of the ETC antenna 121 and the bottom 115a of the notch 115 provided in the common ground plane 110. The distance is E. Since the distance H is sufficiently smaller than the distance E, the distance between the center O of the ETC antenna 121 and the bottom 115a of the notch 115 is substantially equal to the distance E. Therefore, hereinafter, the distance E between the center O of the ETC antenna 121 and the bottom 115a of the notch 115 will be described as a distance E.

  Similarly, let G be the distance between the point 121a on the notch 115 side of the ETC antenna 121 that is perpendicular to the common ground plane 110 and the bottom 115a of the notch 115. Since the distance H is sufficiently smaller than the distance G, the distance between the end side 121a of the ETC antenna 121 and the bottom side 115a of the notch 115 is substantially equal to the distance G. Therefore, hereinafter, the distance G between the end side 121a of the ETC antenna 121 and the bottom side 115a of the notch 115 will be described as a distance G.

  The composite antenna device 100 according to the present embodiment has a notch 115 formed in the ground plane 110 so that the ETC antenna 121 has a stable gain characteristic regardless of the distance between the built-in ETC antenna 121 and the windshield 141. Is provided. By providing the notch 115 at a suitable position on the ground plane 110, the gain characteristics of the ETC antenna 121 can be improved. By appropriately selecting the dimensions of the notch 115 and the like, the ETC antenna 121 and the windshield 141 are provided. It is possible to obtain a stable gain characteristic irrespective of the distance between the two.

  As a preferred installation position of the notch 115, it is preferable that the distance G between the nearest edges between the notch 115 and the ETC antenna 121 is λ / (2π) or more. When the distance G is equal to or less than λ / (2π), the bottom 115a of the notch 115 is present in the near field when viewed from the ETC antenna 121, and the characteristics of the ETC antenna 121 are affected by the bottom 115a. Will change. By making the distance G larger than λ / (2π), the base 115a can be positioned in the far field of the ETC antenna 121 so that the influence is not strongly received. In addition, the distance E between the center O of the ETC antenna 121 and the bottom 115a of the notch 115 is preferably shorter than λ / 2.

  In the present embodiment, the notch 115 is formed at the center of the first end 111 and the protrusions 116 are left at both ends. FIG. 5 shows an example of the front gain of the ETC antenna 121 when the notch 115 is formed and the distance L between the ETC antenna 121 and the windshield 141 is changed. FIG. 5 shows a comparison of changes in the front gain when the horizontal axis is the distance L in the case where the dimensions of the notch 115 are different. In the figure, for comparison, the change in front gain of the ETC antenna when notched portions are not provided is indicated by reference numeral 10. In the figure, the front gain when the distance L is negative indicates a value when the windshield 141 is not interposed.

  Reference numerals 11, 12, and 13 shown in FIG. 5 indicate changes in the front gain of the ETC antenna 121 when the depth D of the notch 115 is 8 mm and the width W of the protrusion 116 is 19 mm, 10 mm, and 8 mm, respectively. Is shown. The dimensions of each notch 115 are shown in the plan views of FIGS. 6 to 8 (respective composite antenna devices 100a, 100b, and 100c). When the width W of the convex part 116 is set as described above, the widths (first lengths) of the notch parts 115 are 52 mm, 70 mm, and 74 mm, respectively, which are longer than the wavelength of the ETC antenna 121. Further, when the width W of the projection 116 is 19 mm, the width of the notch 115 is substantially equal to the width of the radome 101.

  Here, the depth D of the notch 115 is set to 8 mm. At this time, the distance E between the center O of the ETC antenna 120 and the bottom 115a of the notch 115 is 18 mm, which is smaller than λ / 2. . The distance G between the end side 121a of the ETC antenna 121 and the bottom side 115a of the notch 115 is about 14 mm, which is larger than λ / (2π). On the other hand, when the notch is not provided, the distance between the center O of the ETC antenna 121 and the first end 111 of the common ground plate 110 is about 26 mm, which is slightly larger than λ / 2.

  In FIG. 5, in the conventional case (notation 10) where the notch 115 is not provided, the front gain of the ETC antenna varies greatly depending on the distance L. Especially when the distance L is 6 mm or more, a relatively long distance is used as a period. It has greatly increased or decreased. On the other hand, in the composite antenna device 100 of this embodiment, since the notch 115 is provided, the change with respect to the distance L is small, especially when the distance L is 6 mm or more. This increase or decrease in gain has almost no effect on the use of ETC, and can be considered to be almost constant. When the distance L is smaller than 6 mm, it is strongly influenced by the windshield 141, and it is considered that the resonance frequency is shifted and the gain is lowered.

  In FIG. 5, when the notch 115 is not provided, the front gain (symbol 10) of the ETC antenna 121 greatly increases or decreases with a relatively long distance as a period, whereas when the notch 115 is provided. Can shorten the period of change of the front gain (reference numerals 11, 12, and 13), and can see the effect that the change of the front gain is reduced accordingly.

  In the present embodiment, a notch 115 is formed at the center of the first end 111 of the common ground plate 110, and the protrusions 116 are left at both ends. When such a notch 115 is provided, the front gain of the ETC antenna 121 is the depth D of the notch 115 or the distance E between the center O of the ETC antenna 121 and the bottom 115 a of the notch 115. It is also considered that it is influenced by the size of the distance G between the end side 121a of the ETC antenna 121 and the bottom side 115a of the notch 115. Further, it is considered that the front gain of the ETC antenna 121 is also affected by providing the convex portion 116.

  From the result shown in FIG. 5, the distance G between the end side 121a of the ETC antenna 121 and the bottom side 115a of the notch 115 is larger than λ / (2π) by setting the depth D of the notch 115 to 8 mm. When the distance E between the center O of the ETC antenna 121 and the base 115a of the notch 115 is 18 mm which is smaller than λ / 2, it can be seen that the change of the front gain with respect to the distance L can be reduced.

  In the present embodiment, the protrusions 116 are left on both sides of the notch 115, but by leaving such a protrusion 116, a change from the characteristics of the ETC antenna 121 before the notch 115 is provided can be minimized. I try to reduce it. From the results indicated by reference numerals 11, 12, and 13, it can be seen that the change in the front gain is smaller when the width W of the convex portion 116 is smaller, and that the change in the front gain is slightly larger when the width W is increased. By reducing the width W of the convex portion 116, the distance between the convex portion 116 and the ETC antenna 121 is increased, and the convex portion 116 can be sufficiently separated from the near field of the ETC antenna 121.

  As described above, in the composite antenna device 100 of the present embodiment, the notch 115 is formed at a suitable position of the common ground plate 110, and the convex portions 116 are left at both ends thereof, so that the ETC antenna 121 and the front Regardless of the distance from the glass 141, stable gain characteristics can be obtained for the ETC antenna 121.

(Second Embodiment)
A composite antenna device according to a second embodiment of the present invention is shown in FIG. In the composite antenna device 200 of the present embodiment, a trapezoidal notch 215 having a bottom 215a as an upper base is formed. Thereby, the convex part 216 formed in the both ends of the 1st end side 211 is also formed in the trapezoid shape which makes the 1st end side 211 side the upper base. The length (first length) of the base 215a is preferably equal to or longer than the wavelength of the ETC antenna 121.

  An example of the front gain of the ETC antenna 121 when the notch 215 is formed and the distance L between the ETC antenna 121 and the windshield 141 is changed is displayed together with FIG. 5 shown in the first embodiment. In FIG. 5, the code | symbol 21 has shown the change of the front gain of the ETC antenna 121 of this embodiment. In the present embodiment, the change in the front gain of the ETC antenna 121 can be further reduced. By making the notch 215 and the convex part 216 into a trapezoidal shape, it is considered that the influence between the notch 215 of the common ground plate 210 and the ETC antenna 121 on the front gain can be further reduced.

(Third embodiment)
A composite antenna device according to a third embodiment of the present invention is shown in FIGS. In the composite antenna device 300 (300a, 300b) of the present embodiment, the first end 311 side is notched to the left and right ends without providing a convex portion. The depths D of the notches 315 are 8 mm and 4 mm, respectively. FIG. 12 shows a comparative example (referred to as a composite antenna device 300x) in which the depth D of the notch 315 is 16 mm (the notch is formed up to the tip of the radome 101). FIG. 13 shows an example of a change in front gain when the horizontal axis is the distance L as a comparison with the above case where the dimensions of the notch 315 are different.

  From FIG. 13, in the composite antenna device 300 of the present embodiment in which the depth D of the notch 315 is 8 mm (reference numeral 21) or 4 mm (reference numeral 22), compared to the case where the notch part indicated by reference numeral 10 is not provided. The change in front gain has been reduced. However, the change in front gain is slightly larger than in the composite antenna devices 100 and 200 of the first embodiment and the second embodiment provided with the convex portions shown in FIG.

  In the case of the comparative example in which the depth D of the notch 315 is further increased to 16 mm (reference numeral 23), the change in the front gain is as large as in the case of reference numeral 10 without the notch part. The direction of change is almost reversed. When the depth D of the notch 315 is 4 mm, 8 mm, and 16 mm, the distance E between the edge 315a of the notch 315 and the center O of the ETC antenna 121 is 22 mm, 18 mm, and 10 mm, respectively. The distances G between the end side 315a of 315 and the end side 121a of the ETC antenna 121 are 18 mm, 14 mm, and 6 mm, respectively. Accordingly, when the depth D of the notch 315 is 4 mm or 8 mm, the distance E is shorter than λ / 2 and the distance G is longer than λ / (2π). On the other hand, when the depth D is 16 mm, the distance G is shorter than λ / (2π).

  From the above results, the distance E between the end side 315a of the notch 315 and the center O of the ETC antenna 121 is made shorter than λ / 2, and the end side 315a of the notch 315 and the end side 121a of the ETC antenna 121 are set. By making the distance G to be longer than λ / (2π), the change in the front gain can be reduced. In the present embodiment, the first end 311 side is notched to both ends with respect to the common ground plate 310. Instead, the ETC antenna 321 is moved forward (first) by the same distance as the depth D of the notch 315. It may be moved to the one end side 311 side). Thereby, the same effect as this embodiment can be acquired.

(Fourth embodiment)
A composite antenna device according to a fourth embodiment of the present invention is shown in FIG. In the composite antenna device 400 of the present embodiment, instead of the notch portions provided in the first to third embodiments, a portion corresponding to the notch portion of the common ground plate 410 is parallel to the ETC antenna 121. It is bent. In FIG. 14, a bent portion 415 having a depth D ′ is provided at the center of the first end side 411, and a convex portion 416 having a width W that is not bent is formed at both ends of the first end side 411.

  By forming the bent portion 415 so as to be parallel to the ETC antenna 121, the received wave from the ETC roadside device is incident on the bent portion 415 about the substantially vertical direction while the vehicle 140 is traveling. As a result, the received wave that has reached the bent portion 415 is reflected in a substantially vertical direction with respect to the bent portion 415 and the windshield 141, and is hardly reflected by the windshield 141 and is transmitted to the outside. . As a result, there is almost no influence from the radio wave reaching the bent portion 415, and the bent portion 415 has substantially the same effect as when the notched portion is formed.

  In FIG. 14, when the depth D ′ of the bent portion 415 is the same size as the depth D of the notch portion 115 of the first embodiment, and the width W of the convex portion 416 is also the same size as that of the first embodiment. That is, the composite antenna device 400 of this embodiment can obtain the same antenna characteristics as the composite antenna device 100 of the first embodiment. Further, not only in the first embodiment, but by making the size of the bent portion 415 the same as that of the cutout portion in the second embodiment or the third embodiment, the same antenna characteristics can be obtained. Is possible.

  Furthermore, when the notched portion is formed and the convex portion is provided, the convex portion is easily deformed (easy to bend), whereas when the bent portion 415 is formed, the bent portion 415 and the convex portion 416 are formed. Are connected to each other, so that an effect that the convex portion 416 is hardly deformed can be obtained. In the present embodiment, the inclination of the bent portion 415 is set to be parallel to the ETC antenna 121. However, even when the bent portion 415 is bent to be parallel to the windshield 141, substantially the same effect is obtained. Is obtained.

  The description in the present embodiment shows an example of the composite antenna device according to the present invention, and the present invention is not limited to this. The detailed configuration and detailed operation of the composite antenna device according to the present embodiment can be changed as appropriate without departing from the spirit of the present invention.

1 is a perspective view of a composite antenna device according to a first embodiment of the present invention. It is a top view of the compound antenna device concerning a 1st embodiment. It is a schematic diagram which shows an example which installed the composite antenna apparatus in the vehicle interior. It is sectional drawing which shows the positional relationship of a common ground board and an ETC antenna part, and a windshield. It is a figure which shows an example of the change of the front gain with respect to the distance of an ETC antenna and a windshield. It is a figure which shows an example of the dimension of a notch part. It is a figure which shows another example of the dimension of a notch part. It is a figure which shows another example of the dimension of a notch part. It is a top view of the compound antenna apparatus concerning a 2nd embodiment. It is a top view of the compound antenna apparatus concerning a 3rd embodiment. It is a top view of another Example of the composite antenna apparatus which concerns on 3rd Embodiment. It is a top view of the composite antenna apparatus of a comparative example. It is a figure which shows another example of the change of the front gain with respect to the distance of an ETC antenna and a windshield. It is a top view of the compound antenna apparatus concerning a 4th embodiment. It is a top view of the conventional composite antenna apparatus.

Explanation of symbols

100, 200, 300, 400 Compound antenna device 101 Radome 110, 210, 310, 410 Common ground plate 111, 211, 311, 411 First edge 115, 215, 315, 415 Notch 116, 216, 416 Protrusion 120 ETC antenna section 121 ETC antenna 122 ETC antenna circuit board 131 GPS antenna 132 VICS antenna 133 Circuit board
140 Vehicle 141 Windshield 142 Instrument Panel 415 Bent

Claims (12)

A composite antenna device in which an ETC antenna and one or more other antennas are arranged on the same common ground plane and are installed in the vicinity of a vehicle windshield indoor side,
The ETC antenna is disposed at a predetermined position on the common ground plane so as to be inclined in the traveling direction,
The composite antenna device, wherein the common ground plate is formed with a notch portion that is notched to a predetermined depth at an end side on which the ETC antenna is inclined. 2. The composite antenna device according to claim 1, wherein the cutout portion is cut out so as to be symmetric with respect to a center line of the common ground plane passing through a center of the ETC antenna. 3. The composite antenna apparatus according to claim 1, wherein a distance between the nearest edges between the ETC antenna and the notch is at least 1 / (2π) or more of a wavelength of the ETC antenna. 4. . The predetermined depth is such that the distance between the center of the ETC antenna and the edge of the notch closest to the ETC antenna is shorter than ½ of the wavelength of the ETC antenna. The composite antenna device according to claim 1. The cutout portion is formed in a substantially rectangular shape so that a length of an end closest to the ETC antenna is a predetermined length. Composite antenna device. The cutout portion is formed in a substantially trapezoidal shape so that the length of the end closest to the ETC antenna is a predetermined length. Composite antenna device. The composite antenna device according to claim 5 or 6, wherein the predetermined length is equal to or longer than a wavelength of an ETC antenna. A composite antenna device in which an ETC antenna and one or more other antennas are arranged on the same common ground plane and are installed in the vicinity of a vehicle windshield indoor side,
The ETC antenna is disposed at a predetermined position on the common ground plane so as to be inclined in the traveling direction,
The composite antenna device, wherein the common ground plate is formed with a bent portion bent substantially in parallel with the ETC antenna from a side edge on which the ETC antenna is inclined to a predetermined depth. The composite antenna apparatus according to claim 8, wherein a distance between the nearest edges between the ETC antenna and the bent portion is at least 1 / (2π) or more of a wavelength of the ETC antenna. The predetermined depth is such that the distance between the center of the ETC antenna and the edge of the bent portion closest to the ETC antenna is shorter than ½ of the wavelength of the ETC antenna. Item 10. The composite antenna device according to Item 8 or 9. A GPS antenna is provided as the another antenna,
The composite antenna device according to any one of claims 1 to 10, wherein a ground plane of the GPS antenna is used as the shared ground plane. The composite antenna apparatus according to any one of claims 1 to 11, wherein the ETC antenna is a patch antenna.

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