Vehicle-mounted antenna device

Abstract

An antenna element (200) comprises: a first element (210) including a first power feed unit, and a first element section (210a) and a second element section (210b) disposed on either side of the first power feed unit; and a second element (220) including a second power feed unit, and a third element section (220a) and a fourth element section (220b) disposed on either side of the second power feed unit. At least a part of the first element (210) and at least a part of the second element (220) face each other, and one of the first element section (210a) and the second element section (210b) is disposed at an angle to the other of the first element section (210a) and the second element section (210b).

Description

[Technical field]

[0001] The present invention relates to an in-vehicle antenna device. [Background technology]

[0002] In recent years, antenna devices used in GNSS (Global Navigation Satellite Systems) such as GPS (Global Positioning System) have been developed. In particular, in recent years, for applications such as ADAS (Advanced Driver-Assistance Systems) that require highly accurate position information to be acquired in a short time, there has been a demand for GNSS antennas that support a wide range of bands within a multiband including the L1 band (1559 MHz to 1610 MHz), L band (1525 MHz to 1559 MHz), L5 band (1164 MHz to 1214 MHz), L2 band (1212 MHz to 1254 MHz), and L6 band (1273 MHz to 1284 MHz).

[0003] Patent Documents 1 and 2 describe a stacked patch antenna. This antenna includes a first patch antenna and a second patch antenna. The first patch antenna is stacked on the second patch antenna. The center frequency of the first patch antenna is adjusted to a frequency (e.g., 2.320 GHz to 2.345 GHz) used by SDARS (Satellite Digital Audio Radio Service). The center frequency of the second patch antenna is adjusted to a frequency (e.g., 1.575 GHz) used by GPS.

[0004] Patent Document 3 describes a GPS patch antenna. This antenna includes a dielectric plate, a first antenna arranged on the dielectric plate and compatible with the L1 band, and a second antenna arranged on the dielectric plate and compatible with the L2 band. The size of the dielectric plate is a square plate with a length of 40 mm, a width of 40 mm, and a height of 4 mm. The relative dielectric constant of the dielectric plate is 6.8. The first antenna and the second antenna are formed in a loop shape. The first antenna is located inside the loop of the second antenna. Patent Document 3 describes that this antenna can obtain a high gain of 0 dBic or more and a low axial ratio of 5 dB or less in the L1 band and the L2 band.

[0005] Patent Document 4 describes a multi-band GNSS patch antenna. This antenna includes a dielectric plate, a first conductive plate arranged on one side of the dielectric plate, and a second conductive plate arranged on the opposite side of the dielectric plate. A notch is formed on the outer periphery of the second conductive plate. Patent Document 4 describes that the antenna can be adapted to 1.15 GHz, 1.56 GHz, 1.17645 GHz, and 1.57542 GHz by adjusting various conditions such as the shape of the notch of the second conductive plate. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] U.S. Patent No. 7,277,056 [Patent Document 2] U.S. Patent No. 7,528,780 [Patent Document 3] JP 2018-182362 A [Patent Document 4] JP 2019-041240 A Summary of the Invention [Problem to be solved by the invention]

[0007] As described above, various applications such as ADAS require a GNSS antenna that supports a wide range of bands in a multiband including the L1 band, L band, L5 band, L2 band, and L6 band. In addition, it is desirable that such a GNSS antenna is miniaturized due to various demands such as storage space. However, when a wide band is supported by the patch antennas described in Patent Documents 1 to 4, the size of the patch antenna may need to be increased, and miniaturization of the patch antenna may be difficult. In addition, according to the patch antenna described in Patent Document 3, for example, the antenna is optimized with the L1 band and the L2 band as the resonant frequency. Therefore, a high gain and a low axial ratio are obtained in the L1 band and the L2 band. In contrast, in bands other than the L1 band and the L2 band, a high gain, for example, 0 dBic or more, and a low axial ratio, for example, 5 dB or less, are not obtained. Furthermore, in this patch antenna, the antenna is optimized with the L1 band and the L2 band as the resonant frequency, and the antenna is miniaturized, and the range of bands that the antenna can support is narrowed.

[0008] One example of the object of the present invention is to miniaturize a GNSS antenna that supports a wide range of bands in a multi-band including the L1 band, the L band, the L5 band, the L2 band, and the L6 band. Other objects of the present invention will become apparent from the description of this specification. [Means for solving the problem]

[0009] One aspect of the present invention is The antenna element is operable in at least two of the frequency bands including the L1 band, the L band, the L5 band, the L2 band, and the L6 band, and receives circularly polarized waves; The antenna element comprises: a first element having a first power supply portion, and a first element section and a second element section disposed on either side of the first power supply portion; a second element having a second power supply portion, and a third element section and a fourth element section disposed on either side of the second power supply portion; having At least a portion of the first element and at least a portion of the second element face each other, The vehicle-mounted antenna device is such that one of the first element section and the second element section is disposed at an angle to the other of the first element section and the second element section. Effect of the Invention

[0010] According to the above-described aspects of the present invention, it is possible to miniaturize a GNSS antenna that supports a wide range of bands within a multi-band including the L1 band, the L band, the L5 band, the L2 band, and the L6 band. [Brief description of the drawings]

[0011] [Figure 1] 1 is a perspective view of an in-vehicle antenna device according to an embodiment; [Diagram 2] FIG. 2 is a diagram showing a state where the cover and the ground plate are removed from FIG. [Diagram 3] 3 is a diagram for explaining details of the inclination of each of the first element section and the second element section with respect to a direction parallel to the mounting surface of the base in the example shown in FIG. 2. FIG. [Figure 4] FIG. 4 is a diagram showing a first modified example of FIG. 3. [Diagram 5] FIG. 4 is a diagram showing a second modified example of FIG. 3. [Figure 6] FIG. 4 is a diagram showing a third modified example of FIG. 3. [Figure 7] FIG. 4 is a diagram for explaining details of a region between opposing portions of a first element and a second element. [Figure 8] 3 is a block diagram showing a first example of the details of the circuit unit shown in FIG. 2. [Figure 9] 3 is a block diagram showing a second example of the details of the circuit unit shown in FIG. 2. [Figure 10] 3 is a block diagram showing a third example of the details of the circuit unit shown in FIG. 2. [Figure 11]3 is a block diagram showing a fourth example of the details of the circuit unit shown in FIG. 2. [Figure 12] 4 is a block diagram showing a fifth example of the details of the circuit unit shown in FIG. 2. [Figure 13] 3 is a block diagram showing a sixth example of the details of the circuit unit shown in FIG. 2. [Figure 14] 2. FIG. 13 is a block diagram showing a seventh example of the details of the circuit section 300 shown in FIG. [Figure 15] 1 is a top view of a first stacked patch antenna in accordance with a first comparative example. FIG. [Figure 16] 16 is a side view of the first stacked patch antenna shown in FIG. [Figure 17] FIG. 11 is a perspective view of a second stacked patch antenna according to a second comparative example. [Figure 18] 5 is a graph showing frequency characteristics of gain and axial ratio in the range of 1100 MHz to 1700 MHz of the antenna element according to the embodiment (FIG. 2). [Figure 19] 17 is a graph showing frequency characteristics of gain and axial ratio in the range of 1100 MHz to 1700 MHz of the first stacked patch antenna (FIGS. 15 and 16) according to Comparative Example 1. [Figure 20] 18 is a graph showing frequency characteristics of gain and axial ratio in the range of 1100 MHz to 1700 MHz of the second stacked patch antenna (FIG. 17) according to comparative example 2. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, similar components are given similar reference numerals and the description will be omitted as appropriate.

[0013] In this specification, ordinal numbers such as "first," "second," "third," etc., unless otherwise specified, are used merely to distinguish between similarly named configurations and do not imply any particular characteristics (e.g., order or importance) of the configurations.

[0014] Fig. 1 is a perspective view of an in-vehicle antenna device 10 according to an embodiment of the present invention. Fig. 2 is a view in which a cover 500 and a ground plate 600 are removed from Fig. 1.

[0015] In FIG. 1 and FIG. 2, the first direction X is the front-rear direction of the vehicle-mounted antenna device 10. The positive direction of the first direction X (the direction indicated by the arrow indicating the first direction X) is the front direction of the vehicle-mounted antenna device 10. The negative direction of the first direction X (the opposite direction to the direction indicated by the arrow indicating the first direction X) is the rear direction of the vehicle-mounted antenna device 10. The second direction Y is the left-right direction of the vehicle-mounted antenna device 10. The second direction Y intersects with the first direction X, specifically, is perpendicular to it. The positive direction of the second direction Y (the direction indicated by the arrow indicating the second direction Y) is the left direction of the vehicle-mounted antenna device 10 when viewed from the rear of the vehicle-mounted antenna device 10 (the negative direction of the first direction X). The negative direction of the second direction Y (the opposite direction to the direction indicated by the arrow indicating the second direction Y) is the right direction of the vehicle-mounted antenna device 10 when viewed from the rear of the vehicle-mounted antenna device 10 (the negative direction of the first direction X). The third direction Z is the up-down direction of the vehicle-mounted antenna device 10. The third direction Z intersects with both the first direction X and the second direction Y, and specifically, is perpendicular to them. The positive direction of the third direction Z (the direction indicated by the arrow indicating the third direction Z) is the upward direction of the vehicle-mounted antenna device 10. The negative direction of the third direction Z (the opposite direction to the direction indicated by the arrow indicating the third direction Z) is the downward direction of the vehicle-mounted antenna device 10. The same applies to the subsequent figures.

[0016] The outline of the vehicle-mounted antenna device 10 will be described with reference to FIG. 1 and FIG.

[0017] 2, the vehicle-mounted antenna device 10 includes a base 100, an antenna element 200, a circuit section 300, a first feeder line 410, and a second feeder line 420. As shown in FIG.

[0018] In the example shown in FIG. 1, the vehicle-mounted antenna device 10 is disposed on a ground plate 600. In this embodiment, the ground plate 600 is the roof of the vehicle. That is, the vehicle-mounted antenna device 10 is attached to the upper surface side of the roof (ground plate 600) of the vehicle. When the vehicle-mounted antenna device 10 is attached to the roof of the vehicle, the positive direction of the first direction X is the forward direction of the vehicle, and the negative direction of the first direction X is the backward direction of the vehicle. As will be described in detail later, when the vehicle-mounted antenna device 10 (antenna element 200) is disposed on the ground plate 600, the antenna element 200 can operate better as a GNSS antenna than when the vehicle-mounted antenna device 10 (antenna element 200) is not disposed on the ground plate 600. However, the ground plate 600 to which the vehicle-mounted antenna device 10 is attached is not limited to the roof of the vehicle.

[0019] The base 100 has a first base member 110 and a second base member 120. The first base member 110 and the second base member 120 have a thickness in the up-down direction (third direction Z) of the vehicle-mounted antenna device 10. The first base member 110 is formed of an insulating material, for example, a resin. The second base member 120 is located on the first base member 110. The second base member 120 is formed of a conductive material, for example, a metal. The length of each of the first base member 110, the second base member 120, and the base 100 in the front-rear direction (first direction X) of the vehicle-mounted antenna device 10 is longer than the length of each of the first base member 110, the second base member 120, and the base 100 in the left-right direction (second direction Y) of the vehicle-mounted antenna device 10.

[0020] The base 100 may be composed of only the second base member 120, or may be composed of the second base member 120 and a metal plate. Furthermore, the base 100 may be composed of the first base member 110 and a metal plate, or may be composed of the first base member 110, the second base member 120, and a metal plate.

[0021] The antenna element 200 is mounted on the mounting surface 122 of the base 100 (second base member 120) via a first feed line 410 and a second feed line 420. The first feed line 410 and the second feed line 420 will be described in detail later. The antenna element 200 can operate in frequency bands including the L1 band (1559 MHz to 1610 MHz), the L band (1525 MHz to 1559 MHz), the L5 band (1164 MHz to 1214 MHz), the L2 band (1212 MHz to 1254 MHz), and the L6 band (1273 MHz to 1284 MHz), and receives circularly polarized waves. For example, the gain and axial ratio of the antenna element 200 in each of the L1 band, the L band, the L5 band, the L2 band, and the L6 band are 2.0 dBic or more and 4.0 dB or less, respectively. The antenna element 200 does not have to be capable of operating in all of the L1 band, the L band, the L5 band, the L2 band, and the L6 band, but may be capable of operating in at least two or more of these bands.

[0022] The antenna element 200 has two elements, a first element 210 and a second element 220 .

[0023] The first element 210 has two element sections, a first element section 210a and a second element section 210b. The second element 220 has two element sections, a third element section 220a and a fourth element section 220b.

[0024] The first element section 210a includes two arms, a first arm 212a and a second arm 212b. The second element section 210b includes two arms, a third arm 212c and a fourth arm 212d. The third element section 220a includes two arms, a fifth arm 222a and a sixth arm 222b. The fourth element section 220b includes two arms, a seventh arm 222c and an eighth arm 222d.

[0025] As will be described in detail below, the first arm 212a, the second arm 212b, the third arm 212c, and the fourth arm 212d each include a first portion 214a, a second portion 214b, a third portion 214c, and a fourth portion 214d. As will be described in detail below, the fifth arm 222a, the sixth arm 222b, the seventh arm 222c, and the eighth arm 222d each include a fifth portion 224a, a sixth portion 224b, a seventh portion 224c, and an eighth portion 224d.

[0026] Each of the first element section 210a and the second element section 210b of the first element 210 and the third element section 220a and the fourth element section 220b of the second element 220 is formed of a conductive plate, specifically, a metal plate. The first element section 210a and the second element section 210b of the first element 210 have a portion that operates as a self-similar antenna or an antenna equivalent thereto. The third element section 220a and the fourth element section 220b of the second element 220 have a portion that operates as a self-similar antenna or an antenna equivalent thereto. A "self-similar antenna" is an antenna whose shape remains similar even if the scale (size ratio) is changed, such as a biconical antenna or a bowtie antenna. The portion that operates as a self-similar antenna or an antenna equivalent thereto will be described in detail later.

[0027] The circuit section 300 is mounted on the mounting surface 122 of the base 100. The circuit section 300 has, for example, an integrated circuit (IC). The circuit section 300 is electrically connected to the first element 210 and the second element 220 via a first power supply line 410 and a second power supply line 420, respectively.

[0028] The lower end (end on the negative side in the third direction Z) of the first feed line 410 and the lower end (end on the negative side in the third direction Z) of the second feed line 420 are physically and electrically connected to the circuit unit 300, for example, via solder. The upper end (end on the positive side in the third direction Z) of the first feed line 410 and the upper end (end on the positive side in the third direction Z) of the second feed line 420 are physically and electrically connected to the first element 210 and the second element 220, for example, via solder. Each of the first feed line 410 and the second feed line 420 is, for example, a coaxial line. The first feed line 410 extends parallel to the height direction of the vehicle-mounted antenna device 10 between the lower end of the first feed line 410 and the upper end of the first feed line 410. The second feeder line 420 extends parallel to the height direction of the in-vehicle antenna device 10 between the lower end of the second feeder line 420 and the upper end of the second feeder line 420 .

[0029] In this embodiment, the first feed line 410 and the second feed line 420 serve as supports for supporting the first element 210 and the second element 220 on the mounting surface 122 of the base 100. However, the method for supporting the first element 210 and the second element 220 on the mounting surface 122 of the base 100 is not limited to this example.

[0030] The length of each of the first feeder 410 and the second feeder 420 in the height direction of the vehicle-mounted antenna device 10 is approximately λ / 4 (λ: wavelength at the operating frequency of the antenna element 200). Approximately λ / 4 does not only mean strict λ / 4, but also means a length slightly deviated from λ / 4 (for example, a length within a range of λ / 4 to ±λ / 10). The operating frequency of the antenna element 200 is, for example, a central frequency in the L1 band, the L band, the L5 band, the L2 band, and the L6 band. However, the operating frequency of the antenna element 200 does not have to be a central frequency in these bands, and may be a frequency deviated from the central frequency. The length of each of the first feeder 410 and the second feeder 420 in the height direction of the vehicle-mounted antenna device 10 is approximately λ / 4. Furthermore, when the vehicle-mounted antenna device 10 is disposed on the ground plate 600, the antenna element 200 can operate better as a GNSS antenna compared to when the vehicle-mounted antenna device 10 is not disposed on the ground plate 600. However, the vehicle-mounted antenna device 10 does not have to be disposed on the ground plate 600.

[0031] The cover 500 is attached to the upper surface side of the first base member 110 of the base 100, and covers the second base member 120 of the base 100, the antenna element 200, the circuit section 300, the first power supply line 410, and the second power supply line 420. The cover 500 and the base 100 may be attached by a fixing means such as a bolt, or may be attached by a fixing means such as welding or adhesion. As will be described in detail later, in this embodiment, the length of the antenna element 200 in the left-right direction of the vehicle-mounted antenna device 10 is shorter than when the first element section 210a and the second element section 210b of the antenna element 200 are arranged parallel to the mounting surface 122 of the base 100. Therefore, the length of the cover 500 in the left-right direction of the vehicle-mounted antenna device 10 can be shortened compared to when the first element section 210a and the second element section 210b are arranged parallel to the mounting surface 122 of the base 100.

[0032] Next, the shape of the first element 210 will be described in detail with reference to FIG.

[0033] The first element section 210a and the second element section 210b face each other in a predetermined direction, specifically, in the left-right direction of the vehicle-mounted antenna device 10. Specifically, the first element section 210a is located on the left side of the second element section 210b, and the second element section 210b is located on the right side of the first element section 210a. However, the facing direction of the first element section 210a and the second element section 210b is not limited to the left-right direction of the vehicle-mounted antenna device 10, and may be, for example, the front-rear direction of the vehicle-mounted antenna device 10. In addition, in the height direction of the vehicle-mounted antenna device 10, the first element 210 is located above the second element 220. However, in the height direction of the vehicle-mounted antenna device 10, the first element 210 may be located below the second element 220.

[0034] The first element 210 has a first power supply portion that is a portion connected to the upper end of the first power supply line 410. Each of the first element section 210a and the second element section 210b has a first base end portion where the first element section 210a and the second element section 210b are closest to each other and includes the first power supply portion. A first center portion that is approximately the midpoint between the first base end portion of the first element section 210a and the first base end portion of the second element section 210b is the first power supply portion of the first element 210. The "approximate midpoint" does not only mean the exact midpoint between the first base end portion of the first element section 210a and the first base end portion of the second element section 210b, but also means a point that is shifted by a small distance from the exact midpoint (for example, 5% or less of the distance between the first base end portion of the first element section 210a and the first base end portion of the second element section 210b).

[0035] The first arm 212a and the second arm 212b of the first element section 210a are aligned in the front-rear direction of the vehicle-mounted antenna device 10. Specifically, the first arm 212a is located in front of the second arm 212b, and the second arm 212b is located behind the first arm 212a. The first arm 212a and the second arm 212b extend in a direction away from each other from the first base end of the first element section 210a. The third arm 212c and the fourth arm 212d of the second element section 210b are aligned in the front-rear direction of the vehicle-mounted antenna device 10. Specifically, the third arm 212c is located in front of the fourth arm 212d, and the fourth arm 212d is located behind the third arm 212c. The third arm 212c and the fourth arm 212d extend in a direction away from each other from the first base end of the second element section 210b. Furthermore, the first arm 212a and the third arm 212c are aligned in the left-right direction of the vehicle-mounted antenna device 10. Furthermore, the second arm 212b and the fourth arm 212d are aligned in the left-right direction of the vehicle-mounted antenna device 10. The first element 210 is formed by joining the first element section 210a and the second element section 210b symmetrically with respect to the first power supply part of the first element 210. Alternatively, the first element section 210a and the second element section 210b may be formed integrally.

[0036] The respective tips (ends opposite to the first base end) of the first arm 212a and the second arm 212b of the first element section 210a are spaced apart from each other and open. That is, the respective tips of the first arm 212a and the second arm 212b of the first element section 210a have open ends. Each open end of the first element section 210a is formed mainly to ensure a certain area of ​​the first element 210 or more in order to ensure low frequencies, particularly to enable use at lower frequencies. In this embodiment, each open end of the first element section 210a has an L-shape. However, the shape of each open end of the first element section 210a is not limited to an L-shape, and may be, for example, a trapezoid, a rhombus, an ellipse, a circle, a triangle, or the like. The tips of the third arm 212c and the fourth arm 212d of the second element section 210b can also have shapes similar to those described above for the tips of the first arm 212a and the second arm 212b of the first element section 210a.

[0037] The width of each of the first arm 212a, the second arm 212b, the third arm 212c, and the fourth arm 212d increases from the first base end toward the tip of each of the first arm 212a, the second arm 212b, the third arm 212c, and the fourth arm 212d. Therefore, the width of each of the first arm 212a, the second arm 212b, the third arm 212c, and the fourth arm 212d in a region far from the first base end is wider than the width of each of the first arm 212a, the second arm 212b, the third arm 212c, and the fourth arm 212d in a region close to the first base end. Furthermore, the distance between the first arm 212a and the third arm 212c increases continuously or in stages from the first base end of the first element section 210a or the first base end of the second element section 210b toward the tip of the first arm 212a or the tip of the third arm 212c. Therefore, the distance between the first arm 212a and the third arm 212c in the region far from the first base end of the first element section 210a or the first base end of the second element section 210b increases continuously or in stages from the first base end of the first element section 210a or the first base end of the second element section 210b toward the tip of the first arm 212a or the tip of the third arm 212c. Second element section 210bThe distance between the first arm 212a and the third arm 212c in the region close to the first base end of the first element section 210a or the first base end of the second element section 210b is wider than the distance between the second arm 212b and the fourth arm 212d in the region close to the first base end of the first element section 210a or the first base end of the second element section 210b. Similarly, the distance between the second arm 212b and the fourth arm 212d is wider continuously or stepwise from the first base end of the first element section 210a or the first base end of the second element section 210b to the tip of the second arm 212b or the tip of the fourth arm 212d. Therefore, the distance between the second arm 212b and the fourth arm 212d in the region far from the first base end of the first element section 210a or the first base end of the second element section 210b is wider than the distance between the second arm 212b and the fourth arm 212d in the region close to the first base end of the first element section 210a or the first base end of the second element section 210b. In this manner, the first arm 212a, the second arm 212b, the third arm 212c, and the fourth arm 212d of the first element 210 operate as a self-similar antenna or an antenna equivalent thereto.

[0038] In this embodiment, the first element section 210a is formed in a substantially C-shape. The substantially C-shape is, for example, a shape formed by removing a portion of a substantially circular shape such as a circle or an ellipse. The first element section 210a has an opening formed between the first arm 212a and the second arm 212b by this substantially C-shape. The first element section 210a may be formed in a substantially U-shape, a substantially V-shape, or a substantially n-shape. The substantially U-shape is, for example, a shape formed by removing a portion of a substantially rectangular shape and rounding the opposite side of the portion of the substantially rectangular shape. The substantially V-shape is, for example, a shape formed by removing a portion of a substantially triangular shape or a substantially rectangular shape such as a trapezoid whose upper side is relatively short compared to its lower side. The substantially n-shape is, for example, a shape formed by removing a portion of a substantially rectangular shape such as a rectangle, a square, or a trapezoid whose upper side is relatively long compared to its lower side. The same applies to the shape of the second element section 210b. The first element section 210a and the second element section 210b are arranged such that an opening of the first element section 210a and an opening of the second element section 210b face in opposite directions to each other.

[0039] As will be described later with reference to FIG. 3, the first element section 210a and the second element section 210b are inclined at approximately equal angles from a direction parallel to the mounting surface 122 of the base 100 (the second direction Y) toward the side where the mounting surface 122 of the base 100 is located (the negative direction side of the third direction Z). In this way, one of the first element section 210a and the second element section 210b is disposed at an angle relative to the other of the first element section 210a and the second element section 210b. The approximately equal angles do not only mean that the angle of inclination of the first element section 210a with respect to the direction parallel to the mounting surface 122 and the angle of inclination of the second element section 210b with respect to the direction parallel to the mounting surface 122 are strictly equal, but also mean that they differ by only a small angle (for example, ±5 degrees or less).

[0040] In this embodiment, when one of the first element section 210a and the second element section 210b is not inclined relative to the other of the first element section 210a and the second element section 210b, for example, the length of the first element 210 in the opposing direction of the first element section 210a and the second element section 210b can be shortened compared to when the first element section 210a and the second element section 210b are arranged parallel to the mounting surface 122 of the base 100. This allows the in-vehicle antenna device 10 to be miniaturized. In addition, in this embodiment, the length of the first element 210 in the height direction of the in-vehicle antenna device 10 can be shortened compared to when the first element section 210a and the second element section 210b are inclined toward the opposite side (positive side of the third direction Z) to the side where the mounting surface 122 is located. Furthermore, in this embodiment, the radiation directivity of the antenna element 200 in the zenith direction (the positive direction of the third direction Z) can be strengthened compared to a case in which the angle of inclination of the first element section 210a with respect to the direction parallel to the mounting surface 122 and the angle of inclination of the second element section 210b with respect to the direction parallel to the mounting surface 122 are different.

[0041] In this embodiment, the first element section 210a is disposed on a plane inclined toward the positive direction of the second direction Y with respect to the third direction Z. However, the first element section 210a does not have to be disposed on this plane. For example, the first element section 210a may be curved or bent at least in part when viewed from the positive or negative direction of the first direction X. The same applies to the second element section 210b.

[0042] Next, the shape of the second element 220 will be described in detail with reference to FIG. 2. In this embodiment, the size connecting the outer edges of the second element 220 (hereinafter referred to as the "outer edge size") is approximately equal to the outer edge size of the first element 210. That is, the first element 210 and the second element 220 have approximately the same shape. "The outer edge size is approximately equal" does not only mean that the outer edge size of the second element 220 is strictly equal to the outer edge size of the first element 210, but also means that the outer edge size is, for example, 95% to 105% of the outer edge size of the first element 210. However, the outer edge size of the second element 220 may be different from the outer edge size of the first element 210.

[0043] The fifth portion 224a, the sixth portion 224b, the seventh portion 224c, and the eighth portion 224d are arranged in a state rotated approximately 90 degrees with respect to the third portion 214c, the fourth portion 214d, the first portion 214a, and the second portion 214b, respectively. "Approximately 90 degrees" means that the rotation angle of the first element 210 with respect to the second element 220 is not only strictly 90 degrees, but also that the rotation angle is slightly different from 90 degrees (for example, ±2.5 degrees or less).

[0044] The third element section 220a and the fourth element section 220b are aligned in the front-rear direction of the in-vehicle antenna device 10. Specifically, the third element section 220a is located in front of the fourth element section 220b, and the fourth element section 220b is located behind the third element section 220a.

[0045] The second element 220 has a second power feed portion that is a portion connected to the upper end of the second power feed line 420. Each of the third element section 220a and the fourth element section 220b has a second base end portion where the third element section 220a and the fourth element section 220b are closest to each other and includes a second power feed portion. A second center portion that is approximately the midpoint between the second base end portion of the third element section 220a and the second base end portion of the fourth element section 220b is the second power feed portion of the second element 220. The "approximate midpoint" means not only the exact midpoint between the second base end portion of the third element section 220a and the second base end portion of the fourth element section 220b, but also a point that is shifted by a small distance from the exact midpoint (for example, 5% or less of the distance between the second base end portion of the third element section 220a and the second base end portion of the fourth element section 220b).

[0046] The fifth arm 222a and the sixth arm 222b of the third element section 220a are aligned in the left-right direction of the in-vehicle antenna device 10. Specifically, the fifth arm 222a is located to the left of the sixth arm 222b, and the sixth arm 222b is located to the right of the fifth arm 222a. The fifth arm 222a and the sixth arm 222b extend in a direction away from each other from the second base end of the third element section 220a. The seventh arm 222c and the eighth arm 222d of the fourth element section 220b are aligned in the left-right direction of the in-vehicle antenna device 10. Specifically, the seventh arm 222c is located to the left of the eighth arm 222d, and the eighth arm 222d is located to the right of the seventh arm 222c. The seventh arm 222c and the eighth arm 222d extend in a direction away from each other from the second base end of the fourth element section 220b. Furthermore, the fifth arm 222a and the seventh arm 222c are aligned in the front-rear direction of the vehicle-mounted antenna device 10. Furthermore, the sixth arm 222b and the eighth arm 222d are aligned in the front-rear direction of the vehicle-mounted antenna device 10. The second element 220 is formed by joining the third element section 220a and the fourth element section 220b symmetrically with respect to the second power supply part of the second element 220. Alternatively, the third element section 220a and the fourth element section 220b may be formed integrally.

[0047] The distal ends (opposite ends of the second base end) of the fifth arm 222a and the sixth arm 222b of the third element section 220a are spaced apart from each other and open. That is, the distal ends of the fifth arm 222a and the sixth arm 222b of the third element section 220a have open ends. Each open end of the third element section 220a is formed mainly to ensure a certain area of ​​the second element 220 or more in order to ensure a low frequency range, particularly to enable use at a lower frequency range. In this embodiment, each open end of the third element section 220a has an L-shape. However, the shape of each open end of the third element section 220a is not limited to an L-shape, and may be, for example, a trapezoid, a rhombus, an ellipse, a circle, a triangle, or the like. The tips of the seventh arm 222c and eighth arm 222d of the fourth element section 220b can have shapes similar to those described above for the tips of the fifth arm 222a and sixth arm 222b of the third element section 220a.

[0048] The width of each of the fifth arm 222a, the sixth arm 222b, the seventh arm 222c, and the eighth arm 222d increases from the second base end toward the tip of each of the fifth arm 222a, the sixth arm 222b, the seventh arm 222c, and the eighth arm 222d. Therefore, the width of each of the fifth arm 222a, the sixth arm 222b, the seventh arm 222c, and the eighth arm 222d in a region far from the second base end is wider than the width of each of the fifth arm 222a, the sixth arm 222b, the seventh arm 222c, and the eighth arm 222d in a region close to the second base end. The distance between the fifth arm 222a and the seventh arm 222c increases continuously or stepwise from the second base end of the third element section 220a or the second base end of the fourth element section 220b toward the tip of the fifth arm 222a or the tip of the seventh arm 222c. Therefore, the distance between the fifth arm 222a and the seventh arm 222c in a region far from the second base end of the third element section 220a or the second base end of the fourth element section 220b is wider than the distance between the fifth arm 222a and the seventh arm 222c in a region close to the second base end of the third element section 220a or the second base end of the fourth element section 220b. Similarly, the interval between the sixth arm 222b and the eighth arm 222d is increased continuously or stepwise from the second base end of the second element section 210b or the second base end of the fourth element section 220b to the tip of the sixth arm 222b or the tip of the eighth arm 222d. Therefore, the interval between the sixth arm 222b and the eighth arm 222d in the region far from the second base end of the third element section 220a or the second base end of the fourth element section 220b is wider than the interval between the sixth arm 222b and the eighth arm 222d in the region close to the second base end of the third element section 220a or the first base end of the fourth element section 220b. In this way, the fifth arm 222a, the sixth arm 222b, the seventh arm 222c, and the eighth arm 222d of the second element 220 operate as a self-similar antenna or an antenna equivalent thereto.

[0049] When each of the first element 210 and the second element 220 includes a portion that operates as a self-similar antenna or an antenna equivalent thereto, the antenna element 200 operates, for example, as a tapered slot antenna in a relatively high frequency band, and operates, for example, as a loop antenna in a relatively low frequency band. In addition, in a specific frequency band in an intermediate frequency band between the relatively high frequency band and the relatively low frequency band, the antenna element 200 operates as a dipole antenna. In addition, in a band between the relatively high frequency band, the relatively low frequency band, and the intermediate frequency band, the antenna element 200 operates in a state in which the operating principles of those antennas are combined, that is, as a composite antenna. Therefore, it is possible to stably operate over a wide frequency band despite being a single antenna element.

[0050] In this embodiment, each of the third element section 220a and the fourth element section 220b is formed in, for example, a generally C-shape, a generally U-shape, a generally V-shape, or a generally n-shape, as described above for the first element section 210a.

[0051] The rate of change (rate of increase) of the width of each arm of the second element 220 from the second base end to the tip of each arm may be different from the rate of change (rate of increase) of the width of each arm of the first element 210 from the first base end to the tip of each arm. For example, the rate of change (rate of increase) of the width of each arm of the second element 220 may be smaller than the rate of change (rate of increase) of the width of each arm of the first element 210.

[0052] The first arm 212a and the fifth arm 222a include opposing portions, i.e., a first portion 214a and a fifth portion 224a, respectively. The first portion 214a of the first element section 210a and the fifth portion 224a of the third element section 220a face each other. Specifically, the first portion 214a of the first element section 210a and the fifth portion 224a of the third element section 220a face each other substantially in parallel.

[0053] The second arm 212b and the seventh arm 222c include opposing portions, i.e., the second portion 214b and the seventh portion 224c, respectively. The second portion 214b of the first element section 210a and the seventh portion 224c of the fourth element section 220b face each other. Specifically, the second portion 214b of the first element section 210a and the seventh portion 224c of the fourth element section 220b face each other substantially in parallel.

[0054] The third arm portion 212c and the sixth arm portion 222b are opposed to each other, that is, Third part 214c and a sixth portion 224b. The third portion 214c of the first element section 210a and the sixth portion 224b of the third element section 220a face each other. Specifically, the third portion 214c of the first element section 210a and the sixth portion 224b of the third element section 220a face each other substantially in parallel.

[0055] The fourth arm 212d and the eighth arm 222d include opposing portions, i.e., the fourth portion 214d and the eighth portion 224d, respectively. The fourth portion 214d of the first element section 210a and the eighth portion 224d of the fourth element section 220b face each other. Specifically, the fourth portion 214d of the first element section 210a and the eighth portion 224d of the fourth element section 220b face each other substantially in parallel.

[0056] Each part of the first element 210 and each part of the second element 220 facing each other approximately parallel means not only that each part of the first element 210 and each part of the second element 220 facing each other strictly parallel, but also that one of each part of the first element 210 and each part of the second element 220 is inclined at a slight angle (e.g., ±2.5 degrees or less) from a direction parallel to the other of each part of the first element 210 and each part of the second element 220.

[0057] As described above, at least a part of the first element 210 and at least a part of the second element 220 face each other. More specifically, split rings (a shape in which a part of a ring is cut out and made to face each other) are formed between the facing parts of the first element 210 and the second element 220, that is, between the first part 214a of the first element 210 and the fifth part 224a of the second element 220, between the second part 214b of the first element 210 and the seventh part 224c of the second element 220, between the third part 214c of the first element 210 and the sixth part 224b of the second element 220, and between the fourth part 214d of the first element 210 and the eighth part 224d of the second element 220. This allows the band that the antenna element 200 can support to be expanded to the relatively lower frequency band side.

[0058] As described above, the first element section 210a is arranged in a state rotated by approximately 90 degrees with respect to the second element section 210b. In this case, the direction of polarization of the first element 210 and the direction of polarization of the second element 220 are orthogonal to each other. Specifically, since the first element 210 and the second element 220 have approximately the same shape, there is almost no difference in amplitude and phase between the linearly polarized wave of the first element 210 and the linearly polarized wave of the second element 220, which are orthogonal to each other, and the antenna element 200 receives a circularly polarized wave.

[0059] Next, the inclination of each of the first element section 210a and the second element section 210b with respect to the direction parallel to the mounting surface 122 of the base 100 will be described with reference to Figs. 3 to 6. As will be described later with reference to Figs. 3 to 6, at least one of the first element section 210a and the second element section 210b can be inclined from the direction parallel to the mounting surface 122 of the base 100 toward the side where the mounting surface 122 is located (the negative direction side of the third direction Z) or the opposite side to the side where the mounting surface 122 is located (the positive direction side of the third direction Z). This allows one of the first element section 210a and the second element section 210b to be arranged at an angle with respect to the other of the first element section 210a and the second element section 210b.

[0060] FIG. 3 is a diagram for explaining details of the inclination of each of the first element section 210a and the second element section 210b with respect to a direction parallel to the mounting surface 122 of the base 100 in the example shown in FIG.

[0061] FIG. 3 shows a part of the base 100, the first element 210 and the second element 220 of the antenna element 200, and the first and second feeder lines 410 and 420 when viewed from the front of the vehicle-mounted antenna device 10 (FIG. 1 or 2). In FIG. 3, the dashed lines passing through the upper ends of the first and second feeder lines 410 and 420 indicate a direction parallel to the mounting surface 122 of the base 100. θ1 in FIG. 3 indicates the angle of inclination of the first element section 210a with respect to the direction parallel to the mounting surface 122 of the base 100. θ2 in FIG. 3 indicates the angle of inclination of the second element section 210b with respect to the direction parallel to the mounting surface 122 of the base 100. In FIG. 3, the second element 220 is not shown. As described above, the facing portions of the first element 210 and the second element 220 are arranged substantially parallel to each other. The matters explained here with respect to FIG. 3 also apply to FIGS. 4 to 6 described below.

[0062] As described above, in the example shown in FIG. 3 (FIG. 2), the inclination angle θ1 of the first element section 210a with respect to the direction parallel to the mounting surface 122 of the base 100 and the inclination angle θ2 of the second element section 210b with respect to the direction parallel to the mounting surface 122 of the base 100 are substantially equal. Each of the angles θ1 and θ2 is, for example, greater than 0 degrees and equal to or less than 70 degrees. In FIGS. 4 to 6 described below, the angles θ1 and θ2 are, for example, greater than 0 degrees and equal to or less than 70 degrees unless otherwise specified. When the angles θ1 and θ2 are each within the above range, a decrease in the characteristics (e.g., gain or axial ratio) of the antenna element 200 when the first element section 210a and the second element section 210b are arranged parallel to each other is fully tolerated. Possible In this way, it is possible to shorten the length of the first element 210 in the opposing direction of the first element section 210a and the second element section 210b while keeping the length within a reasonable range.

[0063] FIG. 4 is a diagram showing a first modified example of FIG.

[0064] The first element section 210a and the second element section 210b are inclined at different angles from a direction parallel to the mounting surface 122 of the base 100 toward the side where the mounting surface 122 of the base 100 is located. In the example shown in Fig. 4, the inclination angle θ1 of the first element section 210a with respect to the direction parallel to the mounting surface 122 of the base 100 is larger than the inclination angle θ2 of the second element section 210b with respect to the direction parallel to the mounting surface 122 of the base 100.

[0065] The inclination angle θ1 of the first element section 210 a with respect to the direction parallel to the mounting surface 122 of the base 100 may be smaller than the inclination angle θ2 of the second element section 210 b with respect to the direction parallel to the mounting surface 122 of the base 100 .

[0066] In this modification as well, when one of the first element section 210a and the second element section 210b is not arranged at an incline with respect to the other of the first element section 210a and the second element section 210b, the length of the first element 210 in the opposing direction of the first element section 210a and the second element section 210b can be shortened, for example, compared to a case in which the first element section 210a and the second element section 210b are arranged parallel to the mounting surface 122 of the base 100. Also in this modification as well, the length of the first element 210 in the height direction of the in-vehicle antenna device 10 (FIG. 1 or FIG. 2) can be shortened, compared to a case in which the first element section 210a and the second element section 210b are inclined toward the side opposite to the side where the mounting surface 122 is located. Furthermore, in this modified example, by adjusting the angle of inclination of each of the first element section 210a and the second element section 210b with respect to a direction parallel to the mounting surface 122 of the base 100, the radiation directivity of the antenna element 200 can be tilted from the zenith direction toward a desired direction.

[0067] FIG. 5 is a diagram showing a second modified example of FIG.

[0068] The first element section 210a and the second element section 210b are inclined from a direction parallel to the mounting surface 122 toward the opposite side to the side on which the mounting surface 122 is located. In the example shown in Fig. 5, the angle θ1 of inclination of the first element section 210a with respect to the direction parallel to the mounting surface 122 of the base 100 and the angle θ2 of inclination of the second element section 210b with respect to the direction parallel to the mounting surface 122 of the base 100 are approximately equal. However, the angle θ1 of inclination of the first element section 210a with respect to the direction parallel to the mounting surface 122 of the base 100 and the angle θ2 of inclination of the second element section 210b with respect to the direction parallel to the mounting surface 122 of the base 100 may be different from each other.

[0069] Even in this modified example, the length of the antenna element 200 in the left-right direction of the vehicle-mounted antenna device 10 (Figure 1 or Figure 2) can be shortened compared to the case where both the first element section 210a and the second element section 210b are arranged parallel to the mounting surface 122 of the base 100.

[0070] FIG. 6 is a diagram showing a third modified example of FIG.

[0071] The first element section 210a is disposed parallel to the mounting surface 122 of the base 100, while the second element section 210b is inclined from a direction parallel to the mounting surface 122 of the base 100 toward the side on which the mounting surface 122 of the base 100 is located. The first element section 210a may be inclined from a direction parallel to the mounting surface 122 of the base 100 toward the side opposite to the side on which the mounting surface 122 of the base 100 is located.

[0072] Even in this modified example, the length of the antenna element 200 in the left-right direction of the vehicle-mounted antenna device 10 (Figure 1 or Figure 2) can be shortened compared to the case where both the first element section 210a and the second element section 210b are arranged parallel to the mounting surface 122 of the base 100.

[0073] Fig. 7 is a diagram for explaining details of the region between opposing portions of the first element 210 and the second element 220. Fig. 7 shows a cross-sectional view of the first portion 214a of the first element 210 and the fifth portion 224a of the second element 220 in a direction perpendicular to the front-rear direction of the vehicle-mounted antenna device 10.

[0074] The in-vehicle antenna device 10 includes an insulator 230. The insulator 230 is disposed between the first portion 214a of the first element 210 and the fifth portion 224a of the second element 220. The insulator 230 is, for example, a resin. The insulator 230 can suppress contact between the first portion 214a of the first element 210 and the fifth portion 224a of the second element 220. The insulator 230 also serves as a spacer that adjusts the width of the region (gap) between the first portion 214a of the first element 210 and the fifth portion 224a of the second element 220.

[0075] The insulator 230 is connected to the first portion 214a of the first element 210. Second Element 220 The insulator 230 may be disposed not only between the fifth portion 224a of the first element 210 and the fifth portion 224b of the second element 220, but also between other opposing portions of the first element 210 and the second element 220, that is, between the second portion 214b of the first element 210 and the seventh portion 224c of the second element 220, between the third portion 214c of the first element 210 and the sixth portion 224b of the second element 220, and between the fourth portion 214d of the first element 210 and the eighth portion 224d of the second element 220. The insulator 230 does not have to be disposed in all of these four regions, and may be disposed in at least one of these four regions.

[0076] FIG. 8 is a block diagram showing a first example of details of the circuit section 300 shown in FIG.

[0077] The circuit section 300 includes a first stage amplifier 312, a first bandpass filter (first BPF) 322, a second bandpass filter (second BPF) 324, two second stage amplifiers 314 (a first second stage amplifier 314a and a second second stage amplifier 314b) and two attenuators 330 (a first attenuator 330a and a second attenuator 330b).

[0078] The first power feed line 410 and the second power feed line 420 are electrically connected to the circuit unit 300 via the hybrid circuit 430. The hybrid circuit 430 provides a phase difference of 90 degrees between a signal sent to the first power feed line 410 connected to the first element 210 and a signal sent to the second power feed line 420 connected to the second element 220. The hybrid circuit 430 also combines a signal from the first power feed line 410 and a signal from the second power feed line 420. The hybrid circuit 430 is provided, for example, on the lower surface (surface on the negative side of the third direction Z) of the circuit unit 300. In this example, the lower ends (ends on the negative side of the third direction Z) of the first power feed line 410 and the second power feed line 420 are connected to the hybrid circuit 430. In this embodiment, the hybrid circuit 430 exists in the circuit unit 300. However, the hybrid circuit 430 may exist in a region different from the inside of the circuit unit 300. The hybrid circuit 430 also has, for example, a low-pass filter section that imparts a phase difference of -45 degrees to the signal and has a predetermined characteristic impedance (for example, 50Ω), and a high-pass filter section that imparts a phase difference of +45 degrees to the signal and has a predetermined characteristic impedance (for example, 50Ω). These low-pass filter section and high-pass filter section impart a phase difference of 90 degrees between the signal to the first feed line 410 and the signal to the second feed line 420. The hybrid circuit 430 enables the antenna element 200 to receive circularly polarized waves.

[0079] The circuit section 300 functions as an LNA (Low Noise Amplifier). Specifically, first, the signals sent from the first feed line 410 and the second feed line 420 and combined by the hybrid circuit 430 are amplified by the first stage amplifier 312. The signals amplified by the first stage amplifier 312 are sent to the first BPF 322 and the second BPF 324. The first BPF 322 passes signals of, for example, the L1 band and the L band. The second BPF 324 passes signals of, for example, the L5 band, the L2 band, and the L6 band. The signal extracted by the first BPF 322 is amplified by the first second stage amplifier 314a, and then sent to the first cable 510a via the first attenuator 330a. Meanwhile, the signal that passes through the second BPF 324 is amplified by a second second stage amplifier 314b and then sent to a second cable 510b via a second attenuator 330b.

[0080] Fig. 9 is a block diagram showing a second example of the details of the circuit unit 300 shown in Fig. 2. The example shown in Fig. 9 is similar to the example shown in Fig. 8, except for the following points. That is, in the example shown in Fig. 9, signals sent from the first feed line 410 and the second feed line 420 and combined by the hybrid circuit 430 are sent to the first BPF 322 and the second BPF 324 connected in parallel. The signals passed through the first BPF 322 and the second BPF 324 are amplified by the first stage amplifier 312, further amplified by the second stage amplifier 314, and sent to the cable 510 via the attenuator 330.

[0081] 10 is a block diagram showing a third example of the details of the circuit unit 300 shown in FIG. 2. The example shown in FIG. 10 is similar to the example shown in FIG. 9, except that the first BPF 322 and the second BPF 324 connected in parallel are arranged between the first stage amplifier 312 and the second stage amplifier 314. That is, in the example shown in FIG. 10, the signals sent from the first feed line 410 and the second feed line 420 and combined by the hybrid circuit 430 are amplified by the first stage amplifier 312 and sent to the first BPF 322 and the second BPF 324. The signals passed through the first BPF 322 and the second BPF 324 are amplified by the second stage amplifier 314 and sent to the cable 510 via the attenuator 330.

[0082] 11 is a block diagram showing a fourth example of the details of the circuit unit 300 shown in FIG. 2. The example shown in FIG. 11 is similar to the example shown in FIG. 9, except that the first stage amplifier 312 and the second stage amplifier 314 are arranged between the hybrid circuit 430 and the first BPF 322 and the second BPF 324 connected in parallel. That is, in the example shown in FIG. 11, the signals sent from the first feed line 410 and the second feed line 420 and combined by the hybrid circuit 430 are amplified by the first stage amplifier 312, further amplified by the second stage amplifier 314, and sent to the first BPF 322 and the second BPF 324. The signal passed through the first BPF 322 and the signal passed through the second BPF 324 are sent to the cable 510 via the attenuator 330.

[0083] Fig. 12 is a block diagram showing a fifth example of the details of the circuit unit 300 shown in Fig. 2. The example shown in Fig. 12 is similar to the example shown in Fig. 9, except that the two-stage amplifier (the first-stage amplifier 312 and the second-stage amplifier 314 in Fig. 9) is replaced by only a single-stage amplifier (the amplifier 310), and the attenuator 330 (Fig. 9) is not provided. That is, in the example shown in Fig. 12, signals sent from the first feed line 410 and the second feed line 420 and combined by the hybrid circuit 430 are sent to the first BPF 322 and the second BPF 324. The signal that has passed through the first BPF 322 and the signal that has passed through the second BPF 324 are amplified by the amplifier 310 and sent to the cable 510.

[0084] Fig. 13 is a block diagram showing a sixth example of the details of the circuit unit 300 shown in Fig. 2. The example shown in Fig. 13 is similar to the example shown in Fig. 12, except that the amplifier 310 is disposed between the hybrid circuit 430 and the first BPF 322 and the second BPF 324 connected in parallel. That is, in the example shown in Fig. 13, the signals sent from the first feed line 410 and the second feed line 420 and combined by the hybrid circuit 430 are amplified by the amplifier 310 and sent to the first BPF 322 and the second BPF 324. The signal that has passed through the first BPF 322 and the signal that has passed through the second BPF 324 are sent to the cable 510 as is.

[0085] 14 is a block diagram showing a seventh example of the details of the circuit unit 300 shown in FIG. 2. The example shown in FIG. 14 is similar to the example shown in FIG. 10, except that the BPF 320 is arranged instead of the first BPF 322 and the second BPF 324 (FIG. 10). That is, in the example shown in FIG. 14, the signals sent from the first feed line 410 and the second feed line 420 and combined by the hybrid circuit 430 are amplified by the first stage amplifier 312 and sent to the BPF 320. The BPF 320 passes, for example, signals of the L1 band and the L band, and signals of the L5 band, the L2 band, and the L6 band. The signal extracted by the BPF 320 is amplified by the second stage amplifier 314 and sent to the cable 510 via the attenuator 330.

[0086] In the examples shown in Fig. 8 to Fig. 13, an electrical path passing through a BPF (first BPF 322) for extracting signals in the L1 band and L band and an electrical path passing through a BPF (second BPF 324) for passing signals in the L5 band, L2 band, and L6 band are branched off from each other. In the examples shown in Fig. 9 to Fig. 13, the first BPF 322 and the second BPF 324 are connected in parallel. In the examples shown in Fig. 8 to Fig. 13, the gain and axial ratio in the L1 band, L band, L5 band, L2 band, and L6 band can be better than in the case of passing signals in the L1 band and L band and signals in the L5 band, L2 band, and L6 band by a single BPF (BPF 320) as shown in Fig. 14.

[0087] 8 to 14, the circuit section 300 has an amplifier and a bandpass filter after the hybrid circuit 430 with respect to the antenna element 200. Therefore, the circuit section 300 can function as an LNA.

[0088] Fig. 15 is a top view of the first layered patch antenna 910 according to comparative example 1. Fig. 16 is a side view of the first layered patch antenna 910 shown in Fig. 15.

[0089] The first stacked patch antenna 910 includes a first patch antenna 912 and a second patch antenna 914. The second patch antenna 914 is stacked on the first patch antenna 912. When viewed from above the first stacked patch antenna 910, each of the first patch antenna 912 and the second patch antenna 914 has a substantially circular shape. The size of the first stacked patch antenna 910 is 41 mm for length L1, 41 mm for width W1, and 13 mm for height H1.

[0090] FIG. 17 is a perspective view of a second stacked patch antenna 920 according to the second comparative example.

[0091] The second stacked patch antenna 920 includes a third patch antenna 922 and a fourth patch antenna 924. The fourth patch antenna 924 is stacked on the third patch antenna 922. When viewed from above the second stacked patch antenna 920, the third patch antenna 922 and the fourth patch antenna 924 have a substantially square shape. The size of the first stacked patch antenna 910 is 80 mm for the length L2, 80 mm for the width W2, and 7.45 mm for the height H2.

[0092] Fig. 18 is a graph showing frequency characteristics of gain and axial ratio at 1100 MHz to 1700 MHz of the antenna element 200 (Fig. 2) according to the embodiment. Fig. 19 is a graph showing frequency characteristics of gain and axial ratio at 1100 MHz to 1700 MHz of the first stacked patch antenna 910 (Figs. 15 and 16) according to comparative embodiment 1. Fig. 20 is a graph showing frequency characteristics of gain and axial ratio at 1100 MHz to 1700 MHz of the second stacked patch antenna 920 (Fig. 17) according to comparative embodiment 2.

[0093] 18 to 20, the horizontal axis of the graphs indicates frequency. The vertical axis on the left side of the graphs indicates gain (dBic), and the solid line in the graphs indicates the frequency characteristic of gain. The vertical axis on the right side of the graphs indicates axial ratio (dB), and the dashed line in the graphs indicates the frequency characteristic of axial ratio. In the graphs, the areas between the thick vertical line at a frequency of approximately 1165 MHz and the thick vertical line at a frequency of approximately 1285 MHz are the L5 band, the L2 band, and the L6 band. In the graphs, the areas between the thick vertical line at a frequency of approximately 1525 MHz and the thick vertical line at a frequency of approximately 1610 MHz are the L1 band and the L band.

[0094] The size of the antenna element 200 according to the embodiment is 70 mm in length (first direction X in FIG. 2), 35 mm in width (second direction Y in FIG. 2), and 42 mm in height (third direction Z in FIG. 2). In other words, the space required to install the antenna element 200 as viewed from the height direction (third direction Z) of the antenna element 200 is 2450 mm.2 It can be estimated that the area of ​​the first stacked patch antenna 910 according to the first comparative example 1 is 1681 mm 2 The area of ​​the second stacked patch antenna 920 according to the second comparative example 2 can be estimated as a rectangle (41 mm × 41 mm). In addition, the space required for installing the second stacked patch antenna 920 according to the second comparative example 2, as viewed from the height direction, is 6400 mm 2 It can be estimated to be a rectangle with an area of ​​80mm x 80mm.

[0095] From a comparison between the frequency characteristics of the first stacked patch antenna 910 according to the comparative embodiment 1 (FIG. 19) and the frequency characteristics of the second stacked patch antenna 920 according to the comparative embodiment 2 (FIG. 20), in order to obtain sufficient performance (gain of 2.0 dBic or more, axial ratio of 4.0 dB or less) in both gain and axial ratio in the L1 band, L band, L5 band, L2 band, and L6 band in the stacked patch antenna, the stacked patch antenna needs to be at least 6,400 mm from the height direction. 2 On the other hand, from the frequency characteristics of the embodiment (FIG. 15), the antenna element 200 according to the embodiment requires a rectangular space of 2450 mm when viewed from the height direction of the antenna element 200. 2 With a rectangular space having an area of ​​100 mm, sufficient performance (gain of 2.0 dBic or more, axial ratio of 4.0 dB or less) is obtained in both gain and axial ratio in the L1 band, L band, L5 band, L2 band, and L6 band. From this, it can be said that with the antenna element 200 according to the embodiment, sufficient performance (gain of 2.0 dBic or more, axial ratio of 4.0 dB or less) is obtained in both gain and axial ratio in the L1 band, L band, L5 band, L2 band, and L6 band in a space smaller than that of the stacked patch antenna.

[0096] Although the embodiment and modified examples of the present invention have been described above with reference to the drawings, these are merely examples of the present invention, and various configurations other than those described above can also be adopted.

[0097] In this embodiment, the first element 210 and the second element 220 of the antenna element 200 are physically supported on the mounting surface 122 of the base 100 by a first feed line 410 and a second feed line 420. However, the first element 210 and the second element 220 of the antenna element 200 may be physically supported on the mounting surface 122 of the base 100 by an insulating block such as a resin block.

[0098] In this embodiment, the first element 210 and the second element 220 of the antenna element 200 are formed of sheet metal. However, the first element 210 and the second element 220 of the antenna element 200 may be formed of a conductive pattern patterned on an insulating block such as a resin block.

[0099] In this embodiment, the vehicle-mounted antenna device 10 includes a base 100, an antenna element 200, a circuit section 300, a first power feed line 410, and a second power feed line 420. However, the vehicle-mounted antenna device 10 may include one or more other antenna elements. For example, the vehicle-mounted antenna device 10 may include an LTE (London g The antenna element may further include an antenna element for Universal Term Evolution (UTU-U), an antenna element for Vehicle-to-Everything (V2X), and the like.

[0100] In this embodiment, the first feed line 410 and the second feed line 420 are coaxial lines, but may be microstrip lines provided on a substrate.

[0101] According to the present specification, the following aspects are provided. (Aspect 1) Aspect 1 is The antenna element is operable in at least two of the frequency bands including the L1 band, the L band, the L5 band, the L2 band, and the L6 band, and receives circularly polarized waves; The antenna element comprises: a first element having a first power supply portion, and a first element section and a second element section disposed on either side of the first power supply portion; a second element having a second power supply portion, and a third element section and a fourth element section disposed on either side of the second power supply portion; having At least a portion of the first element and at least a portion of the second element face each other, The vehicle-mounted antenna device is such that one of the first element section and the second element section is disposed at an angle to the other of the first element section and the second element section. According to the first aspect, the length of the first element in the opposing direction of the first element section and the second element section can be shortened compared to a case where one of the first element section and the second element section is not arranged at an angle to the other of the first element section and the second element section. Also, according to the first aspect, a part of the first element and a part of the second element face each other. Therefore, the band that the antenna element can support can be expanded. Therefore, it is possible to miniaturize an in-vehicle antenna device that supports a wide range of bands in a multi-band including the L1 band, the L band, the L5 band, the L2 band, and the L6 band. (Aspect 2) Aspect 2 is the first element section having a first portion and a second portion; the second element section has a third portion and a fourth portion; the third element section having a fifth portion and a sixth portion; the fourth element section having a seventh portion and an eighth portion; the first portion of the first element section and the fifth portion of the third element section face each other, the second portion of the first element section and the seventh portion of the fourth element section face each other, the third portion of the second element section and the sixth portion of the third element section face each other, In the in-vehicle antenna device according to aspect 1, the fourth portion of the second element section and the eighth portion of the fourth element section face each other. According to the second aspect, each part of the first element section faces each part of the second element section, so that the band that the antenna element can support can be expanded toward the relatively lower frequency band. (Aspect 3) Aspect 3 is The first element and the second element have substantially the same shape, This is an in-vehicle antenna device as described in aspect 2, wherein each of the fifth portion, the sixth portion, the seventh portion, and the eighth portion is arranged rotated approximately 90 degrees relative to each of the third portion, the fourth portion, the first portion, and the second portion. According to the third aspect, the direction of polarization of the first element and the direction of polarization of the second element are orthogonal to each other. Specifically, since the first element and the second element have substantially the same shape, there is almost no difference in amplitude and phase between the linearly polarized wave of the first element and the linearly polarized wave of the second element, which are orthogonal to each other, and the antenna element receives a circularly polarized wave. (Aspect 4) Aspect 4 is This is an in-vehicle antenna device described in any one of aspects 1 to 3, wherein the first element section and the second element section of the first element, and the third element section and the fourth element section of the second element each have a portion that operates as a self-similar antenna or an antenna equivalent thereto. According to the fourth aspect, the antenna element operates, for example, as a tapered slot antenna in a relatively high frequency band, and operates, for example, as a loop antenna in a relatively low frequency band. In addition, in a specific frequency band in an intermediate frequency band between the relatively high frequency band and the relatively low frequency band, the antenna element operates as a dipole antenna. In addition, in a band between the relatively high frequency band, the relatively low frequency band, and the intermediate frequency band, the antenna element operates in a state in which the operating principles of those antennas are combined, that is, as a composite antenna. Therefore, although it is a single antenna element, it can operate stably over a wide frequency band. (Aspect 5) Aspect 5 is each of the first element section, the second element section, the third element section, and the fourth element section has an opening; the first element section and the second element section are arranged such that the opening of the first element section and the opening of the second element section face opposite each other; This is a vehicle-mounted antenna device described in any one of aspects 1 to 4, wherein the third element section and the fourth element section are arranged so that the opening of the third element section and the opening of the fourth element section face in opposite directions to each other. According to aspect 5, when each of the first element section, the second element section, the third element section and the fourth element section has a portion that operates as a self-similar antenna or an antenna equivalent thereto, the antenna element can operate stably over a wide frequency band. (Aspect 6) Aspect 6 is This is an in-vehicle antenna device described in any one of aspects 1 to 5, wherein each of the first element section, the second element section, the third element section, and the fourth element section is formed in any one of an approximately C-shape, an approximately U-shape, an approximately V-shape, and an approximately n-shape. According to aspect 6, since the shapes of the first element section, the second element section, the third element section and the fourth element section correspond to shapes that operate as a self-similar antenna or an antenna equivalent thereto, the antenna element can operate stably over a wide frequency band. (Aspect 7) Aspect 7 is The in-vehicle antenna device according to any one of aspects 1 to 6, further comprising an insulator at least at one location between the first element and the second element. According to the seventh aspect, the insulator can prevent the opposing portions of the first element and the second element from contacting each other. The insulator also serves as a spacer that adjusts the width of the region (gap) between the opposing portions of the first element and the second element. (Aspect 8) Aspect 8 is a mounting surface on which the antenna element is mounted, This is a vehicle-mounted antenna device described in any one of aspects 1 to 7, wherein at least one of the first element section and the second element section is inclined from a direction parallel to the mounting surface toward the side on which the mounting surface is located or toward the opposite side to the side on which the mounting surface is located. According to aspect 8, one of the first element section and the second element section can be arranged at an angle to the other of the first element section and the second element section. (Aspect 9) Aspect 9 is This is the vehicle-mounted antenna device described in aspect 8, wherein the first element section and the second element section are inclined at approximately equal angles from a direction parallel to the mounting surface toward the side on which the mounting surface is located or toward the opposite side to the side on which the mounting surface is located. According to aspect 9, the radiation directivity of the antenna element toward the zenith can be strengthened compared to a case in which the angle of inclination of the first element section with respect to the direction parallel to the mounting surface and the angle of inclination of the second element section with respect to the direction parallel to the mounting surface are different. (Aspect 10) Aspect 10 is a method for producing a semiconductor device comprising the steps of: This is the vehicle-mounted antenna device described in aspect 8, wherein the first element section and the second element section are inclined at different angles from a direction parallel to the mounting surface toward the side on which the mounting surface is located or toward the opposite side to the side on which the mounting surface is located. According to aspect 10, by adjusting the angle of inclination of each of the first element section and the second element section with respect to a direction parallel to the mounting surface, the radiation directivity of the antenna element can be tilted from the zenith direction toward a desired direction. (Aspect 11) Aspect 11 is a In the in-vehicle antenna device according to aspect 9 or 10, the first element section and the second element section are inclined at an angle greater than 0 degrees and equal to or less than 70 degrees with respect to a direction parallel to the mounting surface. According to aspect 11, it is possible to sufficiently tolerate a deterioration in the characteristics (e.g., gain or axial ratio) of the antenna element when the first element section and the second element section are arranged in parallel with each other. Possible In this way, it is possible to shorten the length of the first element in the opposing direction of the first element section and the second element section while keeping the length within a reasonable range. (Aspect 12) Aspect 12 is a method for producing a In the in-vehicle antenna device according to any one of aspects 1 to 11, the antenna element is disposed on a ground plate. According to aspect 12, the antenna element can operate better as a GNSS antenna, compared to a case in which the antenna element is not disposed on the ground plate. (Aspect 13) Aspect 13 is The in-vehicle antenna device according to any one of aspects 1 to 12, further comprising a hybrid circuit that imparts a phase difference of 90 degrees between a signal sent to the first element and a signal sent to the second element. According to the thirteenth aspect, the hybrid circuit enables the antenna element to receive circularly polarized waves. (Aspect 14) Aspect 14 is a method for producing a a circuit unit connected to the antenna element at a downstream side of the hybrid circuit; In the in-vehicle antenna device according to aspect 13, the circuit section has an amplifier and a bandpass filter. According to the fourteenth aspect, the circuit portion can function as an LNA.

[0102] This application claims priority based on Japanese Patent Application No. 2020-011871, filed on January 28, 2020, the disclosure of which is incorporated herein in its entirety. [Explanation of symbols]

[0103] 10 Vehicle-mounted antenna device 100 base 110 First base member 120 Second base member 122 Mounting surface 200 Antenna Element 210 1st Element 210a First Element Section 210b Second element section 212a 1st arm 212b 2nd arm 212c 3rd arm 212d 4th arm 214a Part 1 214b Part 2 214c Part 3 214d Part 4 220 2nd Element 220a Third Element Section 220b 4th Element Section 222a 5th arm 222b 6th arm 222c 7th arm 222d 8th arm 224a Part 5 224b Part 6 224c Part 7 224d Part 8 230 Insulator 300 Circuit section 310 Amplifier 312 First stage amplifier 314 Second stage amplifier 314a First second stage amplifier 314b second stage amplifier 320 BPF 322 First BPF 324 2nd BPF 330 Attenuator 330a First attenuator 330b Second attenuator 410 1st feeder line 420 2nd feeder line 430 Hybrid Circuit 500 Cover 510 Cable 510a First Cable 510b Second Cable 600 Ground plate 910 First stacked patch antenna 912 1st patch antenna 914 Second patch antenna 920 Second stacked patch antenna 922 3rd patch antenna 924 4th patch antenna X 1st direction Y Second direction Z 3rd direction

Claims

1. an antenna element capable of operating in at least two or more frequency bands including an L1 band, an L band, an L5 band, an L2 band, and an L6 band, and receiving a circularly polarized wave; a base having a mounting surface on which the antenna element is mounted; Equipped with The antenna element comprises: a first element having a first power supply portion, and a first element section and a second element section disposed on either side of the first power supply portion; a second element having a second power supply portion, and a third element section and a fourth element section disposed on either side of the second power supply portion; having At least a portion of the first element and at least a portion of the second element face each other to form a split ring; At least one of the first element section and the second element section is disposed at an angle greater than 0 degrees with respect to a direction parallel to the mounting surface.

2. the first element section having a first portion and a second portion; the second element section having a third portion and a fourth portion; the third element section having a fifth portion and a sixth portion; the fourth element section having a seventh portion and an eighth portion; the first portion of the first element section and the fifth portion of the third element section face each other; the second portion of the first element section and the seventh portion of the fourth element section face each other, the third portion of the second element section and the sixth portion of the third element section face each other, The vehicle-mounted antenna device according to claim 1 , wherein the fourth portion of the second element section and the eighth portion of the fourth element section face each other.

3. The first element and the second element have substantially the same shape, 3. The vehicle-mounted antenna device according to claim 2, wherein each of the fifth portion, the sixth portion, the seventh portion, and the eighth portion is arranged rotated approximately 90 degrees relative to each of the third portion, the fourth portion, the first portion, and the second portion.

4. The vehicle-mounted antenna device according to any one of claims 1 to 3, wherein each of the first element section and the second element section of the first element, and the third element section and the fourth element section of the second element, has a portion that operates as a self-similar antenna or an antenna equivalent thereto.

5. each of the first element section, the second element section, the third element section, and the fourth element section has an opening; the first element section and the second element section are arranged such that the opening of the first element section and the opening of the second element section face opposite each other; The vehicle-mounted antenna device according to any one of claims 1 to 4, wherein the third element section and the fourth element section are arranged such that the opening of the third element section and the opening of the fourth element section face in opposite directions to each other.

6. The vehicle-mounted antenna device according to any one of claims 1 to 5, wherein each of the first element section, the second element section, the third element section, and the fourth element section is formed in any one of an approximately C-shape, an approximately U-shape, an approximately V-shape, and an approximately n-shape.

7. The vehicle-mounted antenna device according to any one of claims 1 to 6, further comprising an insulator at least at one location between the first element and the second element.

8. An antenna device for use in an automobile as described in any one of claims 1 to 7, wherein at least one of the first element section and the second element section is inclined from a direction parallel to the mounting surface toward the side on which the mounting surface is located or toward the opposite side to the side on which the mounting surface is located.

9. 9. The vehicle-mounted antenna device according to claim 8, wherein the first element section and the second element section are inclined at approximately equal angles from a direction parallel to the mounting surface toward the side on which the mounting surface is located or toward the opposite side to the side on which the mounting surface is located.

10. 9. The vehicle-mounted antenna device according to claim 8, wherein the first element section and the second element section are inclined at different angles from a direction parallel to the mounting surface toward the side on which the mounting surface is located or toward the opposite side to the side on which the mounting surface is located.

11. 11. The in-vehicle antenna device according to claim 9, wherein the first element section and the second element section are inclined at an angle greater than 0 degrees and equal to or less than 70 degrees with respect to a direction parallel to the mounting surface.

12. The vehicle-mounted antenna device according to any one of claims 1 to 11, wherein the antenna element is disposed on a ground plate.

13. The vehicle-mounted antenna device according to any one of claims 1 to 12, further comprising a hybrid circuit that imparts a phase difference of 90 degrees between a signal sent to the first element and a signal sent to the second element.

14. a circuit unit connected to the antenna element at a downstream side of the hybrid circuit; The vehicle-mounted antenna device according to claim 13, wherein the circuit portion includes an amplifier and a bandpass filter.

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