Antenna device

Abstract

The antenna device of the present invention is capable of receiving radio waves in at least three different frequency bands with high sensitivity using a simple configuration. The antenna device includes a power supply unit, an antenna having a first antenna unit electrically connected to the power supply unit and a second antenna unit electrically connected to the power supply unit, and an amplifier electrically connected to the power supply unit. The first antenna unit includes a first element including a portion extending in a first direction and a first loop element connected to an end of the first element. The second antenna unit includes a second element including a portion extending in the first direction and a second loop element connected to an end of the second element. The first loop element includes a portion extending in the first direction and a portion extending in a second direction different from the first direction. The second loop element includes a portion extending in the first direction and a portion extending in a third direction opposite to the second direction. The first loop element and the second loop element are located at separate positions.

Description

Technical Field

[0001] The present disclosure relates to an antenna device. Background Art

[0002] In recent years, antenna devices installed in vehicles such as automobiles that incorporate composite antenna elements capable of receiving signals in multiple frequency bands, such as AM broadcast waves, FM broadcast waves, terrestrial digital television broadcast waves, and DAB (Digital Audio Broadcasting), have come into practical use. For example, an antenna device is known that includes multiple antenna elements on the inner side of a spoiler whose outer panel is made of synthetic resin, and that receives multiple radio waves (such as FM broadcast waves, AM broadcast waves, and television broadcast waves) in different frequency bands (see, for example, Patent Document 1).

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 2004-128696 Summary of the Invention

[0006] Technical problem to be solved by the invention

[0007] However, the reception performance of conventional antenna devices for receiving radio waves in the aforementioned multiple frequency bands is not always sufficient.

[0008] The present disclosure provides an antenna device capable of receiving radio waves in at least three different frequency bands with high sensitivity using a simple configuration.

[0009] Technical solutions used to solve technical problems

[0010] The present disclosure provides an antenna device, which is a vehicle component mounted on a vehicle body and includes a component for receiving radio waves in a first frequency band, a second frequency band, and a third frequency band. The antenna device includes: a power supply unit, an antenna having a first antenna unit electrically connected to the power supply unit and a second antenna unit electrically connected to the power supply unit, and an amplifier electrically connected to the power supply unit. The first antenna unit includes a first element including a portion extending in a first direction, and a first loop element having a ring-shaped outer edge connected to an end of the first element on the opposite side from the power supply unit. The second antenna unit includes a second element including a portion extending in the first direction, and a second loop element having a ring-shaped outer edge connected to an end of the second element on the opposite side from the power supply unit. The first loop element includes a portion extending in the first direction and a portion extending in a second direction different from the first direction. The second loop element includes a portion extending in the first direction and a portion extending in a third direction opposite to the second direction. The first loop element and the second loop element are located at positions separated from each other.

[0011] Effects of the Invention

[0012] According to the present disclosure, it is possible to receive radio waves in at least three different frequency bands with high sensitivity using a simple configuration. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is an exploded perspective view illustrating a vehicle component on which the antenna device according to one embodiment can be installed and a vehicle body on which the vehicle component can be mounted.

[0014] Figure 2 This is a cross-sectional view illustrating a vehicle component on which the antenna device according to one embodiment can be installed and a vehicle body on which the vehicle component can be mounted.

[0015] Figure 3 This is a plan view illustrating a vehicle component on which the antenna device according to one embodiment can be installed and a vehicle body on which the vehicle component can be mounted.

[0016] Figure 4 It is a plan view showing a first configuration example of an antenna according to one embodiment.

[0017] Figure 5 It is a plan view showing a second configuration example of the antenna according to one embodiment.

[0018] Figure 6 It is a plan view showing third to seventh configuration examples of the antenna according to one embodiment.

[0019] Figure 7 The antenna capacitance C is shown in the example when the maximum widths H1 and H2 are both 10 mm and 110 mm, and the distances D1 and D2 are fixed at 135 mm.a Graph showing the relationship between antenna widths W1 and W2.

[0020] Figure 8 The antenna capacitance C is shown in the example when the distances D1 and D2 are both 35 mm and 135 mm and the maximum widths H1 and H2 are fixed at 10 mm. a Graph showing the relationship between antenna widths W1 and W2.

[0021] Figure 9 The antenna capacitance C is shown when the distances D1 and D2 are fixed at 135 mm. a Graph showing the relationship between the maximum widths H1 and H2.

[0022] Figure 10 The received voltage V of the antenna 30 is shown as an example when the maximum widths H1 and H2 are both 10 mm and 110 mm and the distances D1 and D2 are fixed at 135 mm. a Graph showing the relationship between antenna widths W1 and W2.

[0023] Figure 11 The received voltage V of the antenna 30 is shown as an example when the distances D1 and D2 are both 35 mm and 135 mm and the maximum widths H1 and H2 are fixed at 10 mm. a Graph showing the relationship between antenna widths W1 and W2.

[0024] Figure 12 The received voltage V of the antenna 30 is shown as an example when the distances D1 and D2 are fixed at 135 mm. a Graph showing the relationship between the maximum widths H1 and H2.

[0025] Figure 13 This is a plan view showing an antenna portion that contributes to receiving VHF band radio waves in the antenna according to one embodiment.

[0026] Figure 14 Display changes include Figure 13 The vertical width H of the antenna part FM and width W FM An example of the measurement results of the average antenna gain in the FM broadcast wave band after .

[0027] Figure 15 Display changes include Figure 13 The vertical width H of the antenna part FM and width W FM An example of the measurement results of the average antenna gain in the DAB band III band.

[0028] Figure 16 Yes Display Figure 14 A graph of the measurement results.

[0029] Figure 17 Yes Display Figure 15 A graph of the measurement results.

[0030] Figure 18 Display changes include Figure 13 An example of the measurement results of the average antenna gain in the FM broadcast wave band after adjusting the aspect ratio of the antenna part.

[0031] Figure 19 This is a plan view showing an antenna portion that facilitates reception of radio waves in the DAB Band III band, among the antennas according to one embodiment.

[0032] Figure 20 Display changes include Figure 19 The vertical width H of the antenna part DAB and width W DAB An example of the measurement results of the average antenna gain in the FM broadcast wave band after .

[0033] Figure 21 Display changes include Figure 19 The vertical width H of the antenna part DAB and width W DAB An example of the measurement results of the average antenna gain in the DAB band III band.

[0034] Figure 22 Yes Display Figure 20 A graph of the measurement results.

[0035] Figure 23 Yes Display Figure 21 A graph of the measurement results.

[0036] Figure 24 Display changes include Figure 19 An example of the measurement results of the average antenna gain in the DAB Band III band after adjusting the aspect ratio of the antenna part.

[0037] Figure 25 Display changes Figure 4 An example of the measurement results of the average antenna gain in the FM broadcast wave band and the DAB Band III band after the loop width of the antenna is increased.

[0038] Figure 26 Is the display changed Figure 4 An example of the measurement results of the average antenna gain in the FM broadcast band and the DAB Band III band after adjusting the distance between the antenna loop elements.

[0039] Figure 27 1 shows an example of measurement results of average antenna gains in the FM broadcast wave band and the DAB Band III band when the distances D1 and D2 from the virtual plane 12 c are changed.

[0040] Figure 28 Yes Display Figure 4 An example of the measurement results of the average antenna gain of the antenna in the UHF band. DETAILED DESCRIPTION

[0041] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. For ease of understanding, the proportions of the various parts in the drawings may be different from the actual proportions. There may be deviations in parallel, right angles, orthogonal, horizontal, vertical, up and down, left and right directions to a degree that does not impair the effects of the present invention. In addition, the shape of the corners is not limited to right angles, and may also be an arc with a circular arc. The X-axis direction, the Y-axis direction, and the Z-axis direction respectively represent the direction parallel to the X-axis, the direction parallel to the Y-axis, and the direction parallel to the Z-axis. The X-axis direction, the Y-axis direction, and the Z-axis direction are orthogonal to each other. The XY plane, the YZ plane, and the ZX plane respectively represent an imaginary plane parallel to the X-axis direction and the Y-axis direction, an imaginary plane parallel to the Y-axis direction and the Z-axis direction, and an imaginary plane parallel to the Z-axis direction and the X-axis direction.

[0042] Figure 1 It is an exploded perspective view illustrating a vehicle component on which the antenna device according to one embodiment can be installed and a vehicle body on which the vehicle component can be mounted. Figure 1 The antenna device 101 shown is an example of an antenna device provided on a vehicle component that can be mounted on a vehicle body. Figure 1 The present invention illustrates an example of an antenna device 101 mounted on a spoiler 18 attached to a liftgate 10, which is a part of a vehicle body. The liftgate 10 is an openable and closable door mounted on the rear portion of the vehicle body and has a window glass 11 mounted thereon. The spoiler 18 is an example of a vehicle component and is a resin member fixed to the upper portion of the liftgate 10. The spoiler 18 has an inner cover 14 and an outer cover 13. The antenna device 101 includes a waterproof connector 16, an antenna 30, and an amplifier 60.

[0043] The waterproof connector 16 is an example of a power supply unit for supplying power to the antenna 30 and is electrically connected to the antenna 30. The waterproof connector 16 is connected to the input terminal of the amplifier 60 via a cable 61 (wiring). The waterproof connector 16 is attached to, for example, an antenna outlet 12b formed in the metal portion 12 of the vehicle body. The antenna outlet 12b is an opening formed on the vehicle exterior surface of the metal portion 12.

[0044] The antenna 30 is a conductor that receives radio waves in at least three different frequency bands. In this example, a portion of the antenna 30 is located inside the spoiler 18, sandwiched between the inner cover 14 and the outer cover 13. The antenna 30 may be built into the spoiler 18 or provided on the outer surface of the spoiler 18. The antenna 30 is a linear conductive member and may be formed, for example, from a wire, conductive paint, a metal rod, a metal plate, or the like.

[0045] The amplifier 60 has an input terminal electrically connected to the waterproof connector 16 and amplifies the signal received by the antenna 30. The signal amplified by the amplifier 60 is supplied to a receiving device (not shown) mounted on the vehicle body. In this example, the amplifier 60 is mounted on the upper portion of the lift door 10.

[0046] Figure 2 This is a cross-sectional view illustrating a vehicle component on which an antenna device according to one embodiment can be installed, and a vehicle body on which the vehicle component can be mounted. A high-mounted stop light 17 can be mounted on a spoiler 18. When the high-mounted stop light 17 is mounted on the spoiler 18, positioning the antenna 30 above the high-mounted stop light 17 can minimize degradation in the antenna 30's sensitivity to receiving radio waves. Furthermore, to minimize degradation in the antenna 30's sensitivity to receiving radio waves, it is preferable to position the antenna 30 so that it does not cross over wiring connected to the high-mounted stop light 17. Figure 2 The outer cover 13 is omitted in the figure.

[0047] The antenna 30 may be formed or mounted on the inner cover 14 or the outer cover 13 (not shown), which are dielectric, or on a dielectric substrate (not shown) fixed to the inner cover 14 or the outer cover 13. Forming the antenna 30 on a dielectric substrate facilitates mounting the antenna 30 on the spoiler 18. Examples of dielectric substrates include printed circuit boards and flexible substrates.

[0048] The element of the antenna 30 is connected to the waterproof connector 16 installed in the antenna outlet 12b of the metal part 12 of the vehicle body through the hole 20 formed in the inner cover 14. In addition, the ZX plane passing through the antenna outlet 12b and perpendicular to the Y-axis direction is defined as the imaginary plane 12c. Figure 4 The antenna 30 is shown as being described in detail.

[0049] Figure 3 This is a top view illustrating a vehicle component on which an antenna device according to one embodiment can be installed, and a vehicle body on which the component can be mounted. Specifically, the view is from a viewpoint above the vehicle. In this example, when viewed from the normal direction (in this example, the Z-axis direction) to a horizontal plane (in this example, the XY plane) with spoiler 18 installed on the vehicle body, antenna 30 intersects edge 12a of metal portion 12 of the vehicle body. Metal portion 12 is, for example, the upper portion of liftgate 10. Figure 2 、3 In the example shown, the metal portion 12 is a flange to which the window glass 11 can be mounted, and the end edge 12a is the edge of the flange.

[0050] By intersecting the antenna 30 and the edge 12a in this manner when viewed in the Z-axis direction, a portion of the antenna 30 does not overlap with the metal portion 12 in the Z-axis direction. This allows a portion of the antenna 30 (a portion of width S2) to be formed that does not overlap with the metal portion 12 in the Z-axis direction, thereby suppressing a decrease in the receiving sensitivity of the antenna 30. Width S2 is the distance in the Y-axis direction from the edge 12a to the end of the spoiler 18. Width S1 is the width of the spoiler 18 in the vehicle width direction. Furthermore, the antenna 30 does not need to intersect with the edge 12a when viewed in the Z-axis direction. Configurations in which the antenna 30 does not intersect with the edge 12a include: a configuration in which the entire antenna 30 overlaps with the metal portion 12 in the Z-axis direction; and a configuration in which the entire antenna 30 does not overlap with the metal portion 12 in the Z-axis direction.

[0051] Figure 4 It is a plan view showing a first configuration example of an antenna according to one embodiment. Figure 4 The antenna 30 shown is formed to be able to receive radio waves in the first frequency band, the second frequency band, and the third frequency band, and resonates at a frequency in each frequency band at least equal to or higher than the VHF band.

[0052] For example, the first frequency band is the MF (Medium Frequency) band of 300kHz to 3MHz, and the second and third frequency bands are the VHF (Very High Frequency) band of 30MHz to 300MHz. In this case, the first frequency band can be set to the AM broadcast wave band included in the MF band, the second frequency band can be set to the FM broadcast wave band included in the VHF band, and the third frequency band can be set to the DAB Band III band included in the VHF band.

[0053] Antenna 30 can further be configured to receive radio waves in a fourth frequency band. In this case, antenna 30 resonates at a frequency within the fourth frequency band. For example, the fourth frequency band is the UHF (Ultra High Frequency) band of 300 MHz to 3 GHz. In this case, the frequency band of terrestrial digital television broadcast waves of 470 MHz to 720 MHz, which is included in the UHF band, can also be set.

[0054] The antenna 30 includes a first antenna portion 40 and a second antenna portion 50. The first antenna portion 40 is an antenna element electrically connected to the waterproof connector 16, and the second antenna portion 50 is an antenna element electrically connected to the waterproof connector 16. The first antenna portion 40 includes a first element 41 and a first loop element 42, and the second antenna portion 50 includes a second element 51 and a second loop element 52. In addition, "electrical connection" is not limited to the following. Figure 4 The illustrated configuration in which the first antenna portion 40 and the second antenna portion 50 are directly connected to the waterproof connector 16 also includes a configuration in which they are connected at a high frequency.

[0055] The first element 41 is a conductor portion including a portion extending in the first direction. In this example, the first element 41 has an end portion 41a connected to the waterproof connector 16 and an end portion 41b on the opposite side of the waterproof connector 16, and has at least one point ( Figure 4 In the case of two bending parts).

[0056] The first loop element 42 is a conductor portion with a ring-shaped outer edge connected to the end 41b of the first element 41 on the side opposite the waterproof connector 16. The first loop element 42 includes portions 43 and 45 extending in a first direction and portions 44 and 46 extending in a second direction different from the first direction. In this example, portions 43 and 45 face each other in the X-axis direction, while portions 44 and 46 face each other in the Y-axis direction.

[0057] The second element 51 is a conductor portion including a portion extending in the first direction. In this example, the second element 51 has an end portion 51a connected to the waterproof connector 16 and an end portion 51b on the opposite side of the waterproof connector 16, and has at least one point ( Figure 4 In the case of two places, the bending part. In addition, the "bending part" is not limited to the bending part Figure 4 The portions of the first element 41 and the second element 51 bent at right angles shown in the figure may be portions including a curve and having an extremely small curvature radius, as long as the extending direction thereof changes.

[0058] The second loop element 52 is a conductor portion with a ring-shaped outer edge connected to the end 51b of the second element 51 on the side opposite the waterproof connector 16. The second loop element 52 includes portions 53 and 55 extending in a first direction and portions 54 and 56 extending in a third direction opposite to the second direction. In this example, portions 53 and 55 face each other in the X-axis direction, while portions 54 and 56 face each other in the Y-axis direction.

[0059] The first loop element 42 and the second loop element 52 are spaced apart from each other. In this example, they are spaced apart in the X-axis direction so that a gap is formed between the first loop element 42 and the second loop element 52. By arranging the first loop element 42 and the second loop element 52 apart from each other, the antenna 30 can receive radio waves in at least three different frequency bands with high sensitivity using a simple configuration.

[0060] exist Figure 4 In the illustrated example, the first direction is the direction away from the metal portion 12 of the vehicle body when viewed from the Z-axis direction. When viewed from the normal to a horizontal plane, with the vehicle component on which the antenna device 101 can be mounted attached to the vehicle body, the first element 41 and the second element 51 intersect the edge 12a of the metal portion 12. This intersection prevents a portion of the antenna 30 from overlapping the metal portion 12 in the Z-axis direction, thereby minimizing a decrease in the antenna 30's reception sensitivity.

[0061] The first element 41 and the second element 51 are connected to different connection points (specifically, terminals) in the waterproof connector 16. The first element 41 is connected to the waterproof connector 16 at end 41a, and the second element 51 is connected to the waterproof connector 16 at end 51a. Because the first element 41 and the second element 51 are connected to the common waterproof connector 16 at different connection points, the first element 41 and the second element 51 can be independently connected to the common waterproof connector 16. In particular, when the first element 41 and the second element 51 are composed of wires such as AV cables, the operation of connecting the first element 41 and the second element 51 to the waterproof connector 16 is facilitated.

[0062] In this example, the first direction is substantially orthogonal to the second and third directions, thereby easily improving the reception sensitivity of antenna 30. "Substantially orthogonal" may include perpendicularity. In this example, the first direction is parallel to the positive Y-axis direction, the second direction is parallel to the negative X-axis direction, and the third direction is parallel to the positive X-axis direction.

[0063] In this example, the outer edge of the first loop element 42 is formed into a roughly rectangular shape, which easily improves the reception sensitivity of the antenna 30. A roughly rectangular shape includes, for example, a shape in which at least one of the four sides and four corners of the rectangle has a curved portion. Furthermore, even if the outer edge of the first loop element 42 is an annular shape other than a roughly rectangular shape, a decrease in reception sensitivity can be suppressed. In this example, the outer edge of the second loop element 52 is formed into a roughly rectangular shape, which easily improves the reception sensitivity of the antenna 30. Even if the outer edge of the second loop element 52 is an annular shape other than a roughly rectangular shape, a decrease in reception sensitivity can be suppressed.

[0064] In this example, the first element 41 and the first loop element 42 have portions extending in the first direction on a straight line parallel to the first direction, so the reception sensitivity of the antenna 30 is easily improved. Figure 4 In the example shown, the first element 41 has a portion extending on an extension line of the portion 43 of the first loop element 42. Similarly, the second element 51 and the second loop element 52 have portions extending in the first direction on a straight line parallel to the first direction, thereby easily improving the reception sensitivity of the antenna 30. Figure 4 In the illustrated example, the second element 51 has a portion extending on an extension line of the portion 53 of the second loop element 52 .

[0065] When the first antenna portion 40 and the second antenna portion 50 are conductors formed on a dielectric substrate (not shown), such as a printed circuit board, mounting the antenna 30 on a vehicle component such as the aforementioned spoiler 18 becomes easier. Furthermore, when the first loop element 42 and the second loop element 52 of the antenna 30 are formed into a substantially rectangular shape, it is preferable that the long sides of each rectangle extend in the X-axis direction (the vehicle width direction). This allows the antenna 30 to be efficiently positioned within the space within the spoiler 18 when mounted on the spoiler 18.

[0066] Figure 5 1 and 2. This is a plan view showing a second configuration example of an antenna according to an embodiment. By citing the above description, descriptions of the same configurations as the first configuration example will be omitted. Figure 5 In the antenna 30A shown, the shape of the portion where the first element 41 and the second element 51 are connected to the waterproof connector 16 is similar to that of the antenna 30 ( Figure 4 )different.

[0067] In antenna 30A, first element 41 and second element 51 are connected to a common connection point 21 (specifically, a terminal) of waterproof connector 16 via a shared connection element 63. First element 41 and second element 51 share connection element 63 extending from common connection point 21, and each of the first and second elements 41 and 51 branches off from connection element 63 and extends independently. Since first element 41 and second element 51 share a portion, antenna 30A can receive radio waves in at least three different frequency bands with high sensitivity using a simple configuration.

[0068] Figure 6 The above description is cited, and the description of the same configuration as the first and second configuration examples is omitted. Figure 6 The antennas 31 to 35 shown in FIG. 31 have the same shape as the antenna 30 ( Figure 4 ) is different, but it can receive radio waves in at least 3 different frequency bands with high sensitivity using a simple structure.

[0069] In antenna 31, the inner sides of the outer edges of the first loop element 42 and the second loop element 52 are filled with a solid conductor. In antenna 32, the first loop element 42 and the second loop element 52 each have four closed loops, each formed by three elements extending in the X-axis direction. In antenna 33, the first loop element 42 and the second loop element 52 each have two closed loops, each formed by one element extending in the X-axis direction. In antenna 34, the first loop element 42 and the second loop element 52 each have one closed loop. In antenna 35, the first loop element 42 and the second loop element 52 each have one open loop, with capacitive coupling occurring at locations extending parallel to each other near the ends of the open loop, forming a pseudo-closed loop.

[0070] Then, Figure 4 The antenna 30 shown is used as an example to describe the antenna capacitance and reception voltage of the antenna 30. A virtual plane passing through the antenna outlet 12b (waterproof connector 16) formed on the surface of the metal portion 12 and perpendicular to the first direction is defined as a virtual plane 12c.

[0071] Let D1 [mm] be the distance from the imaginary plane 12c to the end of the first antenna unit 40 on the first direction side.

[0072] The distance from the imaginary plane 12c to the end of the second antenna portion 50 on the first direction side is represented by D2 [mm].

[0073] The maximum width of the first loop element 42 in the first direction is denoted as H1 [mm].

[0074] The maximum width of the first loop element 42 in the second direction is denoted as L1 [mm].

[0075] The maximum width of the second loop element 52 in the first direction is denoted as H2 [mm].

[0076] The maximum width of the second circuit element 52 in the third direction is represented by L2 [mm].

[0077] The distance between the first loop element 42 and the second loop element 52 is denoted as A. L [mm],

[0078] L1+A L / 2 is recorded as W1[mm],

[0079] L2+A L / 2 is recorded as W2[mm],

[0080] The antenna capacitance of antenna 30 is denoted as C a [pF],

[0081] The antenna capacitance of the first antenna unit 40 is denoted as C a1 [pF],

[0082] The antenna capacitance of the second antenna unit 50 is denoted as C a2 [pF],

[0083] The received voltage of the first antenna unit 40 is denoted as V a1 [dBμV emf ]、

[0084] The received voltage of the second antenna unit 50 is denoted as V a2 [dBμV emf ]、

[0085] The receiving voltage of antenna 30 is recorded as V a [dBμV emf ]、

[0086] k1=1.02×10 -4 k2=7.97×10 -5 k3=2.61×10 -2 、

[0087] k4=1.77×10 -2 k5=9.83×10 -4 k6=2.87×10 -1 、

[0088] l1=3.29×10 -2 , l2=6.99×10 -2 , l3=2.76×10 1 hour,

[0089] The following relationship holds:

[0090] [Mathematical formula 1]

[0091] C a1 =(k1·H1-k2·D1+k3)·W1+k4·H1+k5·D1+k6

[0092] C a2 =(k1·H2-k2·D2+k3)·W2+k4·H2+k5·D2+k6

[0093] C a =C a1 +C a2

[0094] V a1 =-l1·H1+l2·D1+l3

[0095] V a2=-l1·H2+l2·D2+l3

[0096]

[0097] Each of the mathematical expressions in the above mathematical expression 1 has been dimensionally processed.

[0098] Here, when the voltage at the input terminal of the amplifier 60 is recorded as V i [dBμV emf ], the load capacitance from the power supply unit 16 to the amplifier 60 is represented by C i [pF],

[0099] The following relationship holds:

[0100] [Mathematical formula 2]

[0101]

[0102] The above mathematical formula 2 is dimensionless.

[0103] At this time, if the voltage V i [dBμV emf ]The following conditions are met:

[0104] [Mathematical formula 3]

[0105] 15[dBμV emf ]≤V i ≤35[dBμV emf ]

[0106] Therefore, there is no problem in receiving AM broadcast waves with high sensitivity by the antenna 30. The frequency band of AM broadcast waves is within the range of 530 kHz to 1720 kHz.

[0107] More preferably, if the voltage V i [dBμV emf ]The following conditions are met:

[0108] [Formula 4]

[0109] 20[dBμV emf ]≤V i ≤30[dBμV emf ]

[0110] Then, the antenna 30 has no problem in receiving AM broadcast waves with high sensitivity.

[0111] The waterproof connector 16 and the amplifier 60 may be directly connected, or may be connected via a cable 61. When the antenna device 101 includes the cable 61 connecting the waterproof connector 16 and the amplifier 60, the load capacitance C i [pF] can be the input impedance C of amplifier 60 AMP [pF] and the impedance C of the cable 61 cb sum.

[0112] In addition, the above-mentioned antenna capacitance C a1 and C a2 The calculation formula and its coefficients k1~k6 are from Figures 7-9 The graph is derived, the above receiving voltage V a1 and V a2 The calculation formula and its coefficients l1~l3 are from Figures 10-12 Export the chart.

[0113] Figure 7 The antenna capacitance C of the antenna 30 is shown as an example when the maximum widths H1 and H2 are both 10 mm and 110 mm and the distances D1 and D2 are fixed at 135 mm. a In either case, as the antenna widths W1 and W2 increase, the antenna capacitance C a Also increases. Figure 8 The antenna capacitance C of the antenna 30 is shown as an example when the distances D1 and D2 are both 35 mm and 135 mm and the maximum widths H1 and H2 are fixed at 10 mm. a In either case, as the antenna widths W1 and W2 increase, the antenna capacitance C a Also increases. Figure 9 The antenna capacitance C of the antenna 30 is shown as an example when the distances D1 and D2 are fixed at 135 mm. a The relationship between the maximum width H1 and H2 is shown in the graph. Figure 9 The regression equation derived from each point on the graph is equivalent to the antenna capacitance C mentioned above. a1 and C a2 The calculation formula of .

[0114] Figure 10 The received voltage V of the antenna 30 is shown when the maximum widths H1 and H2 are both 10 mm and 110 mm and the distances D1 and D2 are fixed at 135 mm. a The graph of the relationship between the antenna width W1, W2. In either case, the received voltage V a Almost nothing depends on the antenna widths W1, W2. Figure 11The received voltage V of the antenna 30 is shown as an example when the distances D1 and D2 are both 35 mm and 135 mm and the maximum widths H1 and H2 are fixed at 10 mm. a The graph of the relationship between the antenna width W1, W2. In either case, the received voltage V a Almost nothing depends on the antenna widths W1, W2. Figure 12 The received voltage V of the antenna 30 is shown as an example when the distances D1 and D2 are fixed at 135 mm. a The relationship between the maximum width H1 and H2 is shown in the graph. Figure 12 The regression equation derived from each point on the graph is equivalent to the above-mentioned received voltage V a1 and V a2 In addition, Figures 10-12 The receiving voltage V of the antenna 30 a [dBμV emf ] are all average values ​​in the frequency band of AM broadcast waves.

[0115] Figure 4 In the antenna disclosed in the present invention, when L1+L2+A L When set to W, if

[0116] 50[mm]≦W≦1500[mm],

[0117] 10[mm]≦H1≦300[mm],

[0118] 10[mm]≦H2≦300[mm],

[0119] 15[mm]≦D1≦300[mm],

[0120] 15[mm]≦D2≦300[mm],

[0121] FM broadcast waves have a frequency band of 88 MHz to 108 MHz, and DAB Band III has a frequency band of 170 MHz to 240 MHz.

[0122] If 95 [mm] ≤ D1 ≤ 300 [mm] and 95 [mm] ≤ D2 ≤ 300 [mm], the antenna gain of FM broadcast waves increases, and thus FM broadcast waves can be received with higher sensitivity.

[0123] If 115 [mm] ≤ D1 ≤ 300 [mm] and 115 [mm] ≤ D2 ≤ 300 [mm], the antenna gain for FM broadcast waves and the antenna gain for DAB Band III are improved, so FM broadcast waves and DAB Band III radio waves can be received with higher sensitivity.

[0124] In Figure 4 the antennas of the present disclosure such as, in terms of receiving VHF band radio waves with high sensitivity, D1 and D2 are preferably the same, but they may also be different.

[0125] In Figure 4 the antennas of the present disclosure such as, in terms of receiving VHF band radio waves with high sensitivity, H1 and H2 are preferably the same, but they may also be different.

[0126] In Figure 4 the antennas of the present disclosure such as, in terms of receiving FM broadcast waves with high sensitivity, the maximum width L1 is preferably 3.18 times or more and 50 times or less the maximum width H1, more preferably 4.44 times or more and 45 times or less the maximum width H1.

[0127] In Figure 4 the antennas of the present disclosure such as, in terms of receiving radio waves in Band III of DAB with high sensitivity, the maximum width L2 is preferably 0.91 times or more and 25 times or less the maximum width H2, more preferably 1.79 times or more and 20 times or less the maximum width H2.

[0128] In Figure 4 the antennas of the present disclosure such as, in terms of receiving FM broadcast waves with high sensitivity, it is preferable that 250 [mm] ≤ L1 ≤ 550 [mm], more preferably 250 [mm] ≤ L1 ≤ 500 [mm]. In Figure 4 the antennas of the present disclosure such as, in terms of receiving radio waves in Band III of DAB with high sensitivity, it is preferable that 100 [mm] ≤ L2 ≤ 250 [mm], more preferably 125 [mm] ≤ L2 ≤ 225 [mm].

[0129] In Figure 4 the antennas of the present disclosure such as, in terms of receiving FM broadcast waves and radio waves in Band III of DAB with high sensitivity, it is preferable that 0 [mm] < A L ≤ 240 [mm], more preferably 2 [mm] ≤ A L ≤ 240 [mm].

[0130] In Figure 4 the antennas of the present disclosure such as, when the interval between the first element 41 and the second element 51 is set as A, in terms of receiving FM broadcast waves and radio waves in Band III of DAB with high sensitivity, it is preferable that 0 [mm] < A ≤ 240 [mm], more preferably 2 [mm] ≤ A ≤ 240 [mm].

[0131] Figure 13 is a top view showing the antenna portion 30B in the antenna 30 that contributes to receiving VHF band radio waves. Figure 13 The numerical values in represent the length of the element [mm]. Figure 14The figure shows the change in the vertical width H of the antenna 30 including the antenna portion 30B. FM and width W FM An example of the measurement results of the average antenna gain of the vertically polarized wave in the FM broadcast wave band after . Figure 15 The figure shows the change in the vertical width H of the antenna 30 including the antenna portion 30B. FM and width W FM An example of the measurement results of the average antenna gain of vertically polarized waves in the DAB Band III band. Figure 16 Yes Display Figure 14 A graph of the measurement results. Figure 17 Yes Display Figure 15 The graph of the measurement results is shown in FIG. FM =0 is equivalent to Figure 13 A loop pattern is not provided in the antenna portion 30B.

[0132] according to Figures 14 to 17 , after adjusting the vertical width H of the antenna portion 30B FM and width W FM In this case, the average antenna gain of the FM broadcast wave band varies greatly, but the average antenna gain of the DAB Band III band varies little.

[0133] The range above the threshold "-11dB" that allows for high sensitivity reception of FM broadcast waves is:

[0134] 110[mm]≧H FM ≧10[mm],

[0135] 550[mm]≧W FM ≧250[mm].

[0136] The range above the threshold "-10dB" that allows for high sensitivity reception of FM broadcast waves is:

[0137] 90[mm]≧H FM ≧10[mm],

[0138] 500[mm]≧W FM ≧250[mm].

[0139] Figure 18 This figure shows an example of the measurement results of the average antenna gain in the FM broadcast band after varying the aspect ratio of antenna 30, including antenna portion 30B. The aspect ratios shown in the cells with a scalloped pattern indicate that the antenna gain is above the threshold of -11 dB. The aspect ratios shown in the cells with a slashed pattern indicate that the antenna gain is above the threshold of -10 dB.

[0140] Figure 191 is a plan view showing an antenna portion 30C of the antenna 30 that facilitates reception of radio waves in the DAB Band III band. Figure 19 The value in represents the length of the component [mm]. Figure 20 The figure shows the change in the vertical width H of the antenna including the antenna portion 30C. DAB and width W DAB An example of the measurement results of the average antenna gain of the vertically polarized wave in the FM broadcast wave band after . Figure 21 The figure shows the change in the vertical width H of the antenna including the antenna portion 30C. DAB and width W DAB An example of the measurement results of the average antenna gain of vertically polarized waves in the DAB Band III band. Figure 22 Yes Display Figure 20 A graph of the measurement results. Figure 23 Yes Display Figure 21 The graph of the measurement results is shown in FIG. DAB =0 is equivalent to Figure 19 A loop pattern is not provided in the antenna portion 30C.

[0141] according to Figures 20 to 23 , after adjusting the vertical width H of the antenna portion 30C DAB and width W DAB In this case, the average antenna gain of the DAB Band III band varies greatly, but the average antenna gain of the FM broadcast wave band varies little.

[0142] The range above the threshold of -14dB, which allows for high sensitivity reception of DAB Band III radio waves, is as follows:

[0143] 110[mm]≧H DAB ≧10[mm],

[0144] 250[mm]≧W DAB ≧100[mm].

[0145] The range above the threshold of -13dB, which allows for high sensitivity reception of DAB Band III radio waves, is:

[0146] 70[mm]≧H DAB ≧10[mm],

[0147] 225[mm]≧W DAB ≧125[mm].

[0148] Figure 24This figure shows an example of the average antenna gain measurement results in the DAB Band III frequency band after varying the aspect ratio of antenna 30, including antenna portion 30C. The aspect ratios shown in the cells with a scalloped edge indicate that the antenna gain is above the threshold of -14 dB. The aspect ratios shown in the cells with a slashed edge indicate that the antenna gain is above the threshold of -13 dB.

[0149] Figure 25 Is the display changed Figure 4 An example of the measurement results of the average antenna gain in the FM broadcast wave band and the DAB band III band after the loop width of the antenna 30 is increased. The dimensions of each component during the measurement are shown in FIG. Figure 13 and Figure 19 When the vertical widths of the antenna parts 30B and 30C are uniformly changed, the smaller the vertical width, the higher the sensitivity.

[0150] The ranges where the threshold value "-11dB" for receiving FM broadcast waves with high sensitivity and the threshold value "-14dB" for receiving DAB Band III radio waves with high sensitivity are as follows:

[0151] 90[mm]≧H FM ≧0[mm],

[0152] 20[mm]≧H DAB ≧0[mm].

[0153] The ranges where the threshold value "-10dB" for receiving FM broadcast waves with high sensitivity and the threshold value "-13dB" for receiving DAB Band III radio waves with high sensitivity are as follows:

[0154] 60[mm]≧H FM ≧0[mm],

[0155] 10[mm]≧H DAB ≧0[mm].

[0156] Figure 26 Is the display changed Figure 4 An example of the measurement results of the average antenna gain in the FM broadcast wave band and the DAB band III band after the distance between the loop elements of the antenna 30 was changed. The dimensions of each element during the measurement are shown in FIG. Figure 13 and Figure 19 .

[0157] The range above the threshold "-11dB" that allows for high sensitivity reception of FM broadcast waves is:

[0158] 360[mm]≧A L ≧2[mm].

[0159] The range above the threshold of -14dB, which allows for high sensitivity reception of DAB Band III radio waves, is as follows:

[0160] 240[mm]≧A L ≧2[mm].

[0161] Figure 27 Is for Figure 4 The antenna 30 is shown as an example of the measurement results of the average antenna gain in the FM broadcast wave band and the DAB band III band after changing the distance D1 and D2 from the virtual plane 12c. The dimensions of each component during the measurement are shown in FIG. Figure 13 and Figure 19 .

[0162] In the FM broadcast band and Band III, the average antenna gain increases with distance from imaginary plane 12c. To achieve a gain of -10 dB or greater in the FM broadcast band, a distance of at least 90 mm is required. In Band III, even a distance of at least 80 mm produces minimal change in average antenna gain. When the maximum width of spoiler 18 is set to 300 mm, the optimal range is as follows.

[0163] The range above the threshold "-10dB" that allows for high sensitivity reception of FM broadcast waves is:

[0164] 300[mm]≧D1,D2≧115[mm].

[0165] The range above the threshold "-11dB" that allows for high sensitivity reception of FM broadcast waves is:

[0166] 300[mm]≧D1,D2≧95[mm].

[0167] The range above the threshold of -14dB, which allows for high sensitivity reception of Band III radio waves, is as follows:

[0168] 300[mm]≧D1,D2≧115[mm].

[0169] Figure 28 Yes Display Figure 4 An example of the measurement results of the average antenna gain of the antenna 30 in the UHF band. The dimensions of each element during the measurement are shown in FIG. Figure 13 and Figure 19 We confirmed that the antenna can also be used for UHF reception. That is, in addition to AM, FM, and DAB broadcasts, it can also adequately receive terrestrial digital TV broadcasts. The frequency band for terrestrial digital TV broadcasts is 470MHz to 720MHz, and all measurement results for the UHF band represent average antenna gain for horizontally polarized waves.

[0170] While the embodiments have been described above, the technology disclosed herein is not limited to the above-described embodiments. Various modifications and improvements are possible, such as combining or replacing part or all of the other embodiments.

[0171] For example, the antenna device of the present disclosure is not limited to being installed on a resin vehicle component, and may be installed on a vehicle component formed of a material other than resin, as long as it can transmit and receive radio waves with the required sensitivity.

[0172] Explanation of symbols

[0173] 10 Lift Door

[0174] 11 Window Glass

[0175] 12 Metal parts

[0176] 12a End edge

[0177] 12b Antenna removal port

[0178] 12c Imaginary Plane

[0179] 13 outer cover

[0180] 14 Inner cover

[0181] 16 waterproof connector

[0182] 17 High-mounted brake light

[0183] 18 Spoiler

[0184] 20 holes

[0185] 21 connection points

[0186] 30-35 antenna

[0187] 40 First antenna unit

[0188] 41 First Component

[0189] 42 First circuit element

[0190] Sections 43-46

[0191] 50 Second antenna unit

[0192] 51 Second Component

[0193] 52 Second circuit element

[0194] Sections 53-56

[0195] 60 amplifiers

[0196] 61 Cable

[0197] 63 Connecting elements

[0198] 101 Antenna device.

Claims

1. An antenna device, comprising: a vehicle component mounted on a vehicle body, comprising: Power Supply Department, an antenna having a first antenna portion electrically connected to the power supply portion and a second antenna portion electrically connected to the power supply portion, and an amplifier electrically connected to the power supply unit, The first antenna portion includes a first element including a portion extending in a first direction, and a first loop element connected to an end portion of the first element on the opposite side from the power supply portion and having a ring-shaped outer edge. The second antenna portion includes a second element including a portion extending in the first direction, and a second loop element connected to an end portion of the second element on the opposite side from the power supply portion and having a ring-shaped outer edge. The first loop element includes a portion extending in the first direction and a portion extending in a second direction different from the first direction, The second loop element includes a portion extending in the first direction and a portion extending in a third direction opposite to the second direction, The first loop element and the second loop element are located at positions separated from each other, The first direction is a direction away from the metal part of the vehicle body, When the vehicle component is mounted on the vehicle body and viewed from the normal direction of a horizontal plane, the first element and the second element intersect with the end edge of the metal portion. When a virtual plane passing through the antenna outlet formed on the surface of the metal portion and perpendicular to the first direction is defined, Let D1 [mm] be the distance from the imaginary plane to the end of the first antenna portion on the first direction side. The distance from the imaginary plane to the end of the second antenna unit on the first direction side is represented by D2 [mm]. The maximum width of the first loop element in the first direction is recorded as H1 [mm], The maximum width of the first loop element in the second direction is recorded as L1 [mm], The maximum width of the second loop element in the first direction is recorded as H2 [mm], The maximum width of the second loop element in the third direction is recorded as L2 [mm], The distance between the first loop element and the second loop element is denoted as A. L [mm], L1+L2+A L When expressed as W[mm], 50[mm]≦W≦1500[mm], 10[mm]≦H1≦300[mm], 10[mm]≦H2≦300[mm], 15[mm]≦D1≦300[mm], 15[mm]≦D2≦300[mm].

2. The antenna device according to claim 1, wherein When L1+A L / 2 is recorded as W1[mm], L2+A L / 2 is recorded as W2[mm], The antenna capacitance of the first antenna part is denoted as C a1 [pF], The antenna capacitance of the second antenna part is denoted as C a2 [pF], The antenna capacitance of the antenna is recorded as C a [pF], The receiving voltage of the first antenna unit is denoted as V a1 [dBμV emf ]、 The received voltage of the second antenna unit is denoted as V a2 [dBμV emf ]、 The receiving voltage of the antenna is recorded as V a [dBμV emf ]、 k1=1.02×10 -4 、k2=7.97×10 -5 、k3=2.61×10 -2 、 k4=1.77×10 -2 、k5=9.83×10 -4 、k6=2.87×10 -1 、 l1=3.29×10 -2 , l2=6.99×10 -2 , l3=2.76×10 1 hour, [Mathematical formula 1] ， When the voltage at the input of the amplifier is recorded as V i [dBμV emf ]、 The load capacitance from the power supply to the amplifier is represented by C i [pF], [Mathematical formula 2] ， The above mathematical formulas have been dimensionless. The voltage V i [dBμV emf ]satisfy: [Mathematical formula 3] 。 3. The antenna device according to claim 2, wherein The voltage V i [dBμV emf ]satisfy: [Formula 4] 。 4. The antenna device according to claim 2 or 3, wherein: A cable connecting the power supply unit and the amplifier is provided, Load capacitance C i [pF] is the input impedance of the amplifier C AMP [pF] and the cable impedance C cb The sum of [pF].

5. The antenna device according to claim 1 or 2, wherein: The D1 and the D2 are the same.

6. The antenna device according to claim 1 or 2, wherein: The H1 and the H2 are the same.

7. The antenna device according to claim 1 or 2, wherein: A maximum width L1 of the first loop element in the second direction is not less than 3.18 times and not more than 50 times a maximum width H1 of the first loop element in the first direction.

8. The antenna device according to claim 1 or 2, wherein: The maximum width L2 of the second loop element in the third direction is not less than 0.91 times and not more than 25 times the maximum width H2 of the second loop element in the first direction.

9. The antenna device according to claim 1 or 2, wherein: 250[mm]≦L1≦550[mm], 100[mm]≦L2≦250[mm].

10. The antenna device according to claim 1 or 2, wherein: 0[mm]<A L ≦240[mm]。 11. The antenna device according to claim 1 or 2, wherein: The first element and the second element are connected to different connection points in the power supply portion.

12. The antenna device according to claim 1 or 2, wherein: The first element and the second element are connected to a common connection point of the power supply portion via a shared connection element.

13. The antenna device according to claim 1 or 2, wherein: The first direction is substantially orthogonal to the second direction and the third direction.

14. The antenna device according to claim 1 or 2, wherein: The outer edges of the first loop element and the second loop element are substantially rectangular.

15. The antenna device according to claim 1 or 2, wherein: When the interval between the first element and the second element is denoted as A, 0[mm] <A≦240[mm]。 16. The antenna device according to claim 1 or 2, wherein: The first element and the first loop element have portions extending in the first direction on a straight line parallel to the first direction, The second element and the second loop element have portions extending in the first direction on a straight line parallel to the first direction.

17. The antenna device according to claim 1 or 2, characterized in that The first frequency band is a frequency band of AM broadcast waves, The second frequency band is a frequency band of FM broadcast waves, The third frequency band is the frequency band of Band III of DAB.

18. The antenna device according to claim 17, wherein: A radio wave in a fourth frequency band, which is a frequency band of terrestrial digital television broadcast waves, is received.

19. The antenna device according to claim 1 or 2, wherein: The power supply unit, the first antenna unit, and the second antenna unit are conductors formed on a dielectric substrate.

20. The antenna device according to claim 1 or 2, wherein: The vehicle component is made of resin.

21. The antenna device according to claim 1 or 2, wherein: The vehicle component is a spoiler.

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