JP6379504B2 - Glass antenna - Google Patents

Description

  The present invention relates to a glass antenna disposed on the surface of a glass plate, and more particularly to an antenna that obtains flat characteristics over a wide band.

  Broadcasting is performed in a wide band in the UHF band. For example, a terrestrial digital TV broadcast uses a 300 MHz band of 470 to 770 MHz. This requires a band of about ± 25% (150 MHz) of the center frequency (620 MHz).

  On the other hand, it is difficult to design a glass antenna that obtains high sensitivity over the entire wide band of the UHF band.

  As an antenna for solving this problem, Patent Document 1 discloses a UHF band reception antenna with improved reception gain and directivity. The antenna disclosed in Patent Document 1 is an antenna in which a horizontal line and a vertical line whose length are adjusted to a desired frequency band are extended from a common feeding point, and both horizontal and vertical polarizations are provided. Therefore, the directivity can be improved. Furthermore, by providing a plurality of horizontal lines and vertical lines, the resonance frequency is widened, and reception sensitivity can be increased over a wide band.

JP 7-212119 A

  However, in the antenna described in Patent Document 1, when connecting a plurality of horizontal filaments and vertical filaments, if adjacent horizontal filaments or adjacent vertical filaments are close to each other, the extent is as long as the filaments are thickened. Only the effect of widening the reception band was obtained.

  An object of this invention is to provide the glass antenna which can obtain a high sensitivity in the whole region in the wide band of a UHF band.

  That is, this invention is a glass antenna arrange | positioned at the window glass for vehicles, Comprising: The electric power feeding part, The 1st element extended in a predetermined direction from the said electric power feeding part, The said 1st element and a 1st predetermined angle A second element extending from the power supply unit, and a first auxiliary element connected to the first element or the second element at a second predetermined angle and disposed away from the other element. This is a glass antenna.

  Further, the present invention is the glass antenna, wherein the first auxiliary element is disposed substantially parallel to the other element at a distance of 30 mm or more.

  Further, the present invention is the glass antenna, wherein the first auxiliary element is disposed substantially parallel to the other element at a distance of 100 mm or more.

  Further, in the present invention, the first element is an element that extends in a substantially horizontal direction, and the first auxiliary element is connected to the first element and extends in a vertical direction. It is an antenna.

  In addition, the present invention is a glass antenna further comprising at least one second auxiliary element connected to the middle or tip of the first auxiliary element.

  The present invention further includes two second auxiliary elements, one of the second auxiliary elements is connected in the middle of the first auxiliary element, and the other second auxiliary elements are: The glass antenna is connected to a tip of the first auxiliary element.

  Further, the present invention is the glass antenna further comprising at least one third auxiliary element connected to the other element or the power feeding unit.

  Furthermore, in the present invention, the first auxiliary element is connected to the first element, the third auxiliary element is connected to the second element or the power feeding unit, and the first auxiliary element is connected to the first auxiliary element. It is a glass antenna characterized by extending so that it may approach an element.

  In the present invention, the glass antenna is an antenna for receiving a frequency band in which the wavelength of the center frequency is λ, and the wavelength reduction rate of the window glass is α, and the glass antenna extends in the horizontal direction. The length of one element is approximately 2αλ / 3, and the length of the second element extending in the vertical direction is approximately αλ / 3.

  Further, the present invention is the glass antenna characterized in that at least one of the tip end portion of the first element and the tip end portion of the second element is bent.

  Further, the present invention is the glass antenna characterized in that a defogger in which a plurality of heating filaments are provided between the pair of bus bars and the pair of bus bars is disposed on the window glass.

  In the invention, it is preferable that the second antenna is constituted by the heating wire of the defogger, and the feeding portion of the second antenna is provided in a bus bar far from the feeding portion to which the first element is connected. It is a glass antenna.

  The present invention further includes a fourth auxiliary element extending from the defogger bus bar, wherein the fourth auxiliary element is adjacent to the first element, the second element, or the first auxiliary element, and is capacitively coupled. It is a glass antenna characterized by doing.

  According to the exemplary embodiment of the present invention, a broadband and flat characteristic can be obtained.

The front view of the antenna pattern of 1st Example of this invention. The front view of the antenna pattern of 2nd Example of this invention. The front view of the antenna pattern of 3rd Example of this invention. The front view of the antenna pattern of 4th Example of this invention. The front view of the antenna pattern of 5th Example of this invention. The front view of the antenna pattern of 6th Example of this invention. The frequency characteristic figure of the antenna of 4th Example of this invention. The frequency characteristic figure of the antenna of 5th Example of this invention. The frequency characteristic figure of the antenna of 6th Example of this invention. The frequency characteristic figure of the antenna of 6th Example of this invention.

  1 to 6 are views of a glass antenna according to an embodiment of the present invention as viewed from the inside of a vehicle.

  As shown in FIG. 1, a glass antenna according to an embodiment of the present invention is provided on a rear glass of an automobile, and includes a power feeding unit 6, a first element 1 extending from the power feeding unit 6, and a first element 1 from the power feeding unit 6. It has the 2nd element 2 extended | stretched in a different direction, and the 1st auxiliary | assistant element 3 extended | stretched from the 1st element 1. FIG. The first auxiliary element 3 is preferably arranged such that its tip is separated from the second element 2 and extends in the same direction as the second element 2. Note that the separation between the first auxiliary element 3 and the second element 2 means that the two elements are arranged at a distance that allows them to function as independent elements. Specifically, it is desirable that the two elements be arranged at a distance of 30 mm or more and hardly capacitively coupled.

  The first element 1 and the second element 2 desirably extend so as to be substantially orthogonal. More specifically, the first element 1 extends in a substantially horizontal direction from the power feeding unit 6 in order to receive horizontally polarized radio waves, and the second element 2 is for receiving vertically polarized radio waves. Further, it is preferable to extend in a substantially vertical direction from the power feeding unit 6.

  The power feeding unit 6 is connected to a reception amplifier 86 by a connection line (for example, AV electric wire) 85, and the reception amplifier 86 is connected to a receiver by a high frequency cable (for example, a coaxial cable). The receiving amplifier 86 is connected to the ground (vehicle body).

  In addition, as shown in FIG. 2, the first auxiliary element 3 may be disposed such that the tip of the first auxiliary element 3 is separated from the second element 2 and extends in a direction opposite to the extending direction of the second element 2.

  Further, as shown in FIG. 3, the first auxiliary element 3 is arranged with the tip thereof being spaced apart from the first element 1, connected to the second element 2, and extending in the same direction as the extending direction of the first element 1. May be.

  Moreover, you may have the 2nd auxiliary element 4 extended | stretched from the 1st auxiliary element 3, as shown in FIG.4, FIG.5, FIG.6. The second auxiliary element 4 is preferably disposed such that its tip is spaced apart from the first element 1 and extends in the same direction as the extending direction of the first element 1. The second auxiliary element 4 may be connected in the middle of the first auxiliary element 3 or may be connected to the tip portion.

  Furthermore, you may have the 3rd auxiliary | assistant element 5 extended | stretched along the 1st element 1, as shown in FIG.4, FIG.5, FIG.6. The third auxiliary element 5 may extend from the power supply unit 6 or from the second element 2.

  Further, as shown in FIGS. 5 and 6, a bent portion 3 </ b> B may be formed by bending the tip portion of the first auxiliary element 3. The bent portion 3B can also be grasped as the second auxiliary element 4 extending in the right direction.

  Moreover, as shown in FIG. 6, you may form the bending part 2B which bent the front-end | tip part of the 2nd element 2. As shown in FIG. In addition, although illustration is abbreviate | omitted, you may form the bending part which bent the front-end | tip part of the 1st element 1 (for example, upward).

  Furthermore, as shown in FIG. 6, a plurality of second auxiliary elements 4 may be provided. The plurality of second auxiliary elements 4 extend along each other. In this case, one second auxiliary element 4 may be connected in the middle of the first auxiliary element 3, and the other second auxiliary element 4 may be connected to the tip of the first auxiliary element 3.

  Further, as shown in FIG. 6, the antenna of the present embodiment may be disposed on a rear glass 81 provided with a defogger 90.

  Furthermore, as shown in FIG. 6, a fourth auxiliary element 89 extending from the bus bar 93 of the defogger 90 and capacitively coupling in the vicinity of the first element 1 may be provided. Further, a fourth auxiliary element 89 is disposed in the vicinity of any of the first element 1, the second element 2, the first auxiliary element 3, the second auxiliary element 4, and the third auxiliary element 5, and is capacitively coupled. Also good.

  In the antenna according to the embodiment of the present invention, the pattern is printed at a predetermined position on the indoor side of the window glass plate with a conductive ceramic paste at a width of about 0.7 mm, dried, and then baked in a heating furnace. Formed. Alternatively, an antenna may be formed using a conductive pattern formed on a resin film that transmits light, and attached to a glass plate.

  As described above, the embodiment in which the antenna is provided on the rear glass 81 of the automobile has been described with respect to the embodiment of the present invention. However, the antenna according to the embodiment of the present invention may be provided in another location (for example, a windshield and a side glass).

  The length of each element of the antenna according to the embodiment of the present invention is adjusted to a length suitable for receiving a UHF band terrestrial digital TV broadcast wave (470 to 770 MHz), as will be described later in each example. . Note that an antenna suitable for receiving the VHF band as well as the UHF band can be used.

  Next, the effect | action of the glass antenna of embodiment of this invention is demonstrated.

  The antenna of the present embodiment includes a first element 1 extending in a predetermined direction (for example, a horizontal direction) from the power supply unit 6, and a power supply unit at a first predetermined angle with the first element 1 (for example, at a right angle). A second element 2 extending from 6 (for example in the vertical direction) and a first auxiliary connected to the first element 1 at a second predetermined angle (for example a right angle) and spaced apart from the second element 2 Since the element 3 is provided, a broadband and flat characteristic can be obtained.

  In particular, the length of the first element 1 extending in the horizontal direction is approximately 2αλ / 3, and the length of the second element 2 extending in the vertical direction is approximately αλ / 3 (wavelength of center frequency = λ, glass The wavelength shortening rate of α = α), the sensitivity over the entire band of the reception frequency can be adjusted by the first element 1, and the sensitivity of the low frequency side with respect to the vertical polarization can be adjusted by the second element 2. Characteristics can be obtained.

  Further, by providing the first auxiliary element 3 at a position away from the first element 1 and the second element 2, a plurality of parallel elements are provided, thereby improving the antenna sensitivity as a whole in the reception band. Can do.

  In addition, since the first auxiliary element 3 and the second element 2 are arranged approximately in parallel with a distance of 30 mm or more, the capacitive coupling between both elements is weakened, and the first auxiliary element 3 and the second element 2 are mutually connected. Can function as an independent element. For this reason, if both elements are arranged about 30 mm apart, the sensitivity on the high frequency side can be adjusted by adjusting the length and arrangement of the first auxiliary element 3.

  Moreover, since the 1st auxiliary | assistant element 3 and the 2nd element 2 are 100 mm or more apart and are arrange | positioned substantially parallel, the area | region which attaches the 3rd auxiliary | assistant element 5 can be ensured.

  The first element 1 is an element that extends in a substantially horizontal direction. Since the first auxiliary element 3 is connected to the first element 1 and extends in the vertical direction, the first element 1 has high sensitivity to a vertically polarized signal. Can be obtained.

  Further, since at least one second auxiliary element 4 connected to the middle or tip of the first auxiliary element 3 is provided, the frequency at which high sensitivity can be obtained in the reception band can be adjusted.

  Further, the sensitivity of the reception band is further improved by connecting one second auxiliary element 4 in the middle of the first auxiliary element 3 and connecting the other second auxiliary element 4 to the tip of the first auxiliary element 3. can do.

  In addition, since at least one third auxiliary element connected to the second element 2 or the power feeding unit 6 is provided, the sensitivity on the high frequency side of the reception band can be improved.

  Further, since the third auxiliary element 5 extends so as to approach the first auxiliary element, the sensitivity of the reception band can be further improved.

  Further, since the bent portion is provided by bending at least one of the tip portion of the first element 1 and the tip portion of the second element 2, the antenna can be arranged in a narrow region without shortening the element length. .

  Even if the antenna and the defogger 90 according to the present embodiment are arranged on the window glass, high sensitivity can be obtained in the UHF reception band.

  Further, the third antenna 60 is constituted by the heating filament 91 of the defogger 90. That is, a diversity antenna is configured by providing the defogger 90 with an antenna power supply unit 95 and using the defogger 90 as an antenna. By receiving diversity signals in the UHF band, sensitivity can be improved and directivity can be improved.

  Moreover, since the 3rd electric power feeding part 95 of the 3rd antenna 60 is provided in the bus bar 93 far from the electric power feeding part 6 to which the 1st element 1 is connected, a diversity effect can be improved.

  In addition, since the fourth auxiliary element 89 extending from the bus bar 93 of the defogger 90 and close to and capacitively couples to the first element 1 is provided, the sensitivity on the high frequency side of the reception band can be adjusted. Also, the sensitivity of the third antenna 60 can be improved.

  Hereinafter, various embodiments of the present invention will be described.

<Example 1>
FIG. 1 is a front view of a glass antenna provided on a rear glass of an automobile, showing an antenna pattern of a first embodiment of the present invention.

  The glass antenna of the first embodiment includes a power supply unit 6, a first element 1 extending from the power supply unit 6 in a substantially horizontal direction (leftward), and a second element extending from the power supply unit 6 in a substantially vertical direction (upward). 2 and a first auxiliary element 3 extending upward from the first element 1. The first auxiliary element 3 is disposed separately from the second element 2 and extends in the same direction (for example, substantially parallel) as the extending direction of the second element 2.

  The length of each element of the glass antenna of the first embodiment is adjusted to a length suitable for receiving the UHF band digital terrestrial television broadcasting band. The length of the first element 1 is 220 mm, the second The length of the element 2 is 75 mm, and the length of the first auxiliary element 3 is 50 mm. That is, when the wavelength shortening rate α of the rear glass 81 is 0.7 and the center frequency (wavelength = λ) of the terrestrial digital television broadcast band is 620 MHz, the length of the first element 1 is approximately 2αλ / 3.

  In the first embodiment, the sensitivity over the entire band of the reception frequency can be adjusted by the first element 1, and the sensitivity on the low frequency side can be adjusted by the second element 2, and a flat characteristic can be obtained in the entire band. .

  In addition, by providing the first auxiliary element 3 at a position away from the first element 1 and the second element 2, a plurality of parallel elements are provided separately. As a result, the antenna sensitivity can be improved overall in the reception band. That is, impedance matching over the entire band of the reception frequency is difficult only with the two elements 1 and 2 extending from the power supply unit, so that the impedance in a wide frequency band becomes close to a desired value by the first auxiliary element 3. Antenna sensitivity can be improved.

  In addition, since the second element 2 contributes to the adjustment of the antenna sensitivity on the low frequency side of the reception frequency and the first auxiliary element 3 contributes to the adjustment of the antenna sensitivity on the high frequency side, the antenna sensitivity in the entire band of the reception frequency. Can be improved.

<Example 2>
FIG. 2 is a front view of a glass antenna provided on a rear glass of an automobile, showing an antenna pattern according to a second embodiment of the present invention.

  In the glass antenna of the second embodiment, the extending direction of the first auxiliary element 3 is different from that of the first embodiment.

  The glass antenna of the second embodiment includes a power feeding unit 6, a first element 1, a second element 2, and a first auxiliary element 3. The first auxiliary element 3 of the second embodiment is disposed separately from the second element 2 and extends in a direction opposite to the extending direction of the second element 2 (for example, substantially parallel).

  Since the configurations of the second embodiment other than those described above are the same as those of the first embodiment, the same reference numerals are given and description thereof is omitted.

  In the second embodiment, as in the first embodiment, flat characteristics can be obtained in the entire band. Note that the installation area of the antenna of the first embodiment can be reduced.

<Example 3>
FIG. 3 is a front view of a glass antenna provided on a rear glass of an automobile, showing an antenna pattern according to a third embodiment of the present invention.

  In the glass antenna of the third embodiment, the arrangement of the first auxiliary elements 3 is different from that of the first embodiment.

  The glass antenna of the third embodiment includes a power feeding unit 6, a first element 1, a second element 2, and a first auxiliary element 3. The first auxiliary element 3 of the third embodiment is arranged separately from the first element 1 and extends from the second element 2 in the same direction (for example, substantially parallel) as the extending direction of the first element 1.

  Since the configuration of the third embodiment other than that described above is the same as that of the first embodiment, the same reference numerals are given and description thereof is omitted.

  In the third embodiment, a flat characteristic can be obtained in the entire band as in the first embodiment described above. Note that the antenna of the first embodiment can obtain higher sensitivity.

<Example 4>
FIG. 4 is a front view of a glass antenna provided on a rear glass of an automobile, showing an antenna pattern according to a fourth embodiment of the present invention.

  The glass antenna of the fourth embodiment is different from the first embodiment in that it has a second auxiliary element 4 and a third auxiliary element 5.

  The glass antenna of the fourth embodiment includes a power feeding unit 6, a first element 1, a second element 2, a first auxiliary element 3, a second auxiliary element 4, and a third auxiliary element 5. The first auxiliary element 3 of the fourth embodiment is spaced apart from the second element 2 and extends in the same direction (for example, substantially parallel) as the extending direction of the second element 2.

  The second auxiliary element 4 is connected to the first auxiliary element 3, is spaced apart from the first element 1, and extends in the same direction (for example, substantially parallel) as the extending direction of the first element 1. The second auxiliary element 4 has a length of 100 mm and is connected to a position 5 mm from the tip of the first auxiliary element 3. The second auxiliary element 4 may be connected in the middle of the first auxiliary element 3 or may be connected to the tip portion.

  The third auxiliary element 5 is connected to the power feeding unit 6 and extends along the first element 1 (for example, substantially parallel). The third auxiliary element 5 may be extended from the second element 2 without extending from the power feeding unit 6. The third auxiliary element 5 has a length of 95 mm and is arranged in parallel with the first element 1 at an interval of 8 mm. The third auxiliary element 5 should be long as long as the tip does not contact the first auxiliary element 3. For this reason, if the 1st auxiliary element 3 and the 2nd element 2 are arrange | positioned 100 mm or more apart, the 3rd auxiliary element 5 can be lengthened.

  Since the configuration of the fourth embodiment other than that described above is the same as that of the first embodiment, the same reference numerals are given and description thereof is omitted.

  In the fourth embodiment, both the second auxiliary element 4 and the third auxiliary element 5 are provided, but a glass antenna having one of the second auxiliary element 4 or the third auxiliary element 5 is also included in the scope of the present invention. It is.

  In the fourth embodiment, the frequency at which high sensitivity is obtained in the reception band can be adjusted by the second auxiliary element 4 connected to the middle or the tip of the first auxiliary element 3. In particular, by connecting the second auxiliary element 4 in the middle of the first auxiliary element 3, it is possible to easily adjust the sensitivity in a specific band while improving the sensitivity in the entire band. Further, the sensitivity of the reception band can be further improved by the third auxiliary element 5.

<Example 5>
FIG. 5 is a front view of a glass antenna provided on a rear glass of an automobile, showing an antenna pattern according to a fifth embodiment of the present invention.

  The glass antenna of the fifth embodiment differs from the fourth embodiment in that a bent portion 3B is formed at the tip of the first auxiliary element 3.

  The glass antenna of the fifth embodiment includes a power feeding unit 6, a first element 1, a second element 2, a first auxiliary element 3, a second auxiliary element 4, and a third auxiliary element 5. The first auxiliary element 3 of the fifth embodiment is disposed separately from the second element 2, and has a main body 3A extending in the same direction (for example, substantially parallel) as the extending direction of the second element 2, and a main body 3A. A bent portion 3B that is bent at a substantially right angle from the tip of the first portion and extends rightward toward the second element 2. The bent portion 3B is disposed separately from the first element 1 and extends in a direction opposite to the extending direction of the first element 1 (for example, substantially parallel). The main body 3A has a length of 50 mm, and the bent portion 3B has a length of 45 mm. Further, the bent portion 3B may be connected to the distal end portion of the first auxiliary element 3 or may be connected in the middle.

  In the first auxiliary element 3, the location where the second auxiliary element 4 is connected to the first auxiliary element 3 and the location where the bent portion 3B is connected to the main body portion 3A are preferably different positions. That is, the second auxiliary element 4 and the bent portion 3B may be connected to the main body portion 3A of the first auxiliary element 3 so as to be stepped.

  Moreover, as above-mentioned, when grasping the bending part 3B as the 2nd auxiliary | assistant element 4 extended | stretched rightward, it is good to connect 2nd auxiliary | assistant elements 4 so that it may mutually differ.

  Since the configuration of the fifth embodiment other than that described above is the same as that of the fourth embodiment, the same reference numerals are given and description thereof is omitted.

  In the fifth embodiment, since the bent portion 3B is provided by bending the distal end portion of the first auxiliary element 3, the antenna can be arranged in a narrow region.

<Example 6>
FIG. 6 is a front view of a glass antenna provided on a rear glass 81 of an automobile, showing an antenna pattern according to a sixth embodiment of the present invention.

  In the glass antenna of the sixth embodiment, an antenna having a configuration similar to that of the glass antenna of the fifth embodiment is mounted as the fourth antenna 70. Furthermore, the first antenna 10, the second antenna 50, the third antenna 60, and the It is composed of five antennas 100. The fourth antenna 70 of the sixth embodiment is different from the glass antenna of the fifth embodiment in that a plurality of second auxiliary elements 4 are provided and a bent portion 2B is formed at the tip of the second element 2.

  The fourth antenna 70 of the sixth embodiment includes a power feeding unit 6, a first element 1, a second element 2, a first auxiliary element 3, a second auxiliary element 4, and a third auxiliary element 5. . The second element 2 of the sixth embodiment includes a main body portion 2A extending in a substantially vertical direction (upward) from the power supply portion 6, and a bent portion 2B bending rightward from the tip of the main body portion 2A and extending rightward. Have The bent portion 2B is disposed apart from the first element 1 and extends in the same direction (for example, substantially parallel) as the extending direction of the first element 1. The main body 2A has a length of 75 mm, and the bent portion 2B has a length of 30 mm. When the wavelength shortening rate α of the rear glass 81 is 0.7 and the center frequency (wavelength = λ) of the digital terrestrial television broadcasting band is 620 MHz, the total length of the second element 2 is approximately αλ / 3. Further, the bent portion 2B may be connected to the tip portion of the second element 2 or may be connected in the middle. When the bent part 2B is connected in the middle of the second element 2, the length of the second element may be considered as the length from the power feeding part 6 to the tip of the bent part 2B.

  The two second auxiliary elements 4 of the sixth embodiment are arranged in parallel with being spaced apart from the first element 1, connected to the first auxiliary element 3, and in the same direction as the extending direction of the first element 1 (for example, Stretched substantially parallel). Each second auxiliary element 4 has a length of 100 mm, and the upper second auxiliary element 4 is connected to a position 5 mm from the tip of the main body 3A of the first auxiliary element 3, and the two second auxiliary elements 4 are 5 mm in length. Are arranged in parallel at intervals of. Two second auxiliary elements 4 may be connected in the middle of the first auxiliary element 3, or one may be connected to the tip.

  Since the configuration of the fourth antenna 70 of the sixth embodiment other than that described above is the same as that of the glass antenna of the fifth embodiment, the same reference numerals are given and description thereof is omitted.

  The fourth antenna 70 of the sixth embodiment may use the glass antenna of any of the above-described embodiments in addition to the illustrated configuration.

  In the fourth antenna 70 of the sixth embodiment, since a plurality of second auxiliary elements 4 are provided, higher sensitivity can be obtained in the reception band. In addition, since the bent portion 2B is formed at the tip of the second element 2, the antenna can be arranged in a narrow region without shortening the element length.

  Next, configurations other than the fourth antenna 70 in the glass antenna of the sixth embodiment will be described.

  The first antenna 10 includes a first power feeding unit 15, a horizontal first element 11, a horizontal second element, a vertical element 31, and auxiliary elements 12 and 13.

  The horizontal first element 11 is connected to the first power feeding unit 15 and extends in a substantially horizontal direction (left direction in the figure). The horizontal second element is connected to the first power feeding unit 15 and extends substantially in parallel with the horizontal first element 11 in the same direction as the horizontal first element 11 (right direction in the drawing). The horizontal second element is folded downward from the main body portion 21 extending from the first power feeding portion 15 and at the end of the main body portion 21, is substantially parallel along the main body portion 21, and approaches the first power feeding portion 15. And a folded portion 22 extending in the direction.

  The vertical element 31 extends from the first power feeding unit 15 in a direction different from the extending direction of the horizontal first element 11 and the extending direction of the horizontal second element. The auxiliary element 12 extends downward from the intersection between the vertical portion and the horizontal portion of the first element, and is then disposed substantially in parallel along the horizontal first element 11. Further, the auxiliary element 12 is arranged close to the defogger 90 (for example, 5 mm apart in parallel) so as to be capacitively coupled to the uppermost heating filament 91 of the defogger 90. The auxiliary element 13 extends rightward from the vertical portion of the first element, and is arranged substantially in parallel along the horizontal first element 11.

  The length of each element of the first antenna 10 is adjusted so as to suitably receive the FM radio broadcast band and the DAB band 3.

  The second antenna 50 includes a plurality of horizontal filaments 52, a plurality of vertical filaments 53 connecting the horizontal filaments 52, a second feeding unit 54 provided at an end of the horizontal filaments 52, and folded portions 56 and 57. Have. One of the horizontal filaments 52 is disposed between the auxiliary element 13 of the first antenna 10 and the folded portion 22. The folded portions 56 and 57 extend upward from the uppermost horizontal filament 52, are folded laterally, and extend close to the horizontal filament 52 (for example, 5 mm apart in parallel). The folded portions 56 and 57 are arranged close to the body flange 82 of the vehicle body (for example, 5 mm apart and in parallel), and the second antenna 50 and the body flange 82 (that is, ground) are capacitively coupled. As for the 2nd antenna 50, each filament is arrange | positioned in an area suitable in order to receive AM radio broadcast band (526.5-1606.5kHz).

  The third antenna 60 is constituted by the filaments of the defogger 90, and the defogger 90 functions as a third antenna.

  The defogger 90 functioning as the third antenna 60 includes a pair of bus bars 93 provided on the left and right sides of the rear glass 81, a plurality of heating wires 91 (horizontal wires) connecting the two bus bars 93, and a plurality of heating wires. It has a vertical line 92 connecting the lines 91. The number of vertical filaments 92 may be one or more.

  The bus bar 93 is provided with a defogger coil 94 and a third power feeding unit 95. That is, one bus bar 93 is connected to the power supply via the defogger coil 94, and the other bus bar 93 is connected to the ground via the defogger coil 94. The defogger coil 94 suppresses noise in the reception frequency band that flows into the third antenna 60 from the power source and the ground.

  The defogger coil 94 and the third power supply unit 95 are arranged at the center of the bus bar 93 with the defogger coil 94 on the upper side and the third power supply unit 95 on the lower side, but the positions where the defogger coil 94 and the third power supply unit 95 are arranged. Can be anywhere on the bus bar 93. Furthermore, the order (upper and lower positional relationship) in which the defogger coil 94 and the third power feeding unit 95 are arranged is not limited to that illustrated.

  The first antenna 10 and the third antenna 60 may constitute a diversity antenna, and at least one of the FM radio broadcast wave and the DAB band 3 broadcast wave may be diversity-received. In this case, when the third antenna 60 (defogger 90) receives the FM radio broadcast wave and the DAB band 3 broadcast wave, the power supply unit 95 is provided in the bus bar 93 far from the first antenna 10 (for example, on the right side). Good.

  Further, the first antenna 10 and the fourth antenna 70 may constitute a diversity antenna and receive TV broadcast waves with diversity.

  The third antenna 60 includes parallel auxiliary filaments 96, 97, 98 extending from the bus bar 93 and a fourth auxiliary element 89.

  The end portions of the parallel auxiliary filaments 96, 97, and 98 are located away from each other. Further, a part of the parallel auxiliary line 96 and a part of the parallel auxiliary line 97 are arranged in close proximity to each other so as to be along each other. Furthermore, a part of the parallel auxiliary line 97 and a part of the parallel auxiliary line 98 are arranged in close proximity to each other so as to be along each other. In this manner, since the two parallel auxiliary filaments 96, 97, and 98 are arranged so as to overlap, each parallel auxiliary filament is capacitively coupled at the end. In addition, it may be arrange | positioned so that not only a part of parallel auxiliary filament but almost all may mutually follow.

  The fourth auxiliary element 89 extends upward from the bus bar 93 on the right side (close to the fourth antenna 70), and bends and extends in the left direction. Note that the fourth auxiliary element 89 may extend from the outermost horizontal filament 91.

  The fifth antenna 100 includes a fifth power feeding unit 101, a plurality of vertical wires, and one horizontal wire.

  Each of the power feeding units 15, 54, 95, 101 is connected to a reception amplifier by a connection line (for example, an AV electric wire), and the reception amplifier is connected to a receiver by a high frequency cable (for example, a coaxial cable). The receiving amplifier is connected to the ground (vehicle body).

  In the sixth embodiment, since diversity reception is performed by the first antenna 10 and the fourth antenna 70, it becomes easier to receive incoming waves, and reception performance can be improved.

<Characteristics of antenna>
Next, the characteristics of the antenna of this embodiment will be described.

  The following (FIGS. 7 to 10) is an explanation of antenna sensitivity when the arrangement or length of elements described below is changed, and the configuration of other elements is not changed. The antenna sensitivity is a value obtained by measuring the antenna sensitivity in all directions (360 degrees) in the horizontal plane and calculating the average.

  FIG. 7 shows the gain (sensitivity) of the fourth antenna 70 with respect to a vertically polarized signal in the terrestrial digital TV broadcast band according to the presence or absence of the first auxiliary element 3 in the antenna of the sixth embodiment. The fourth antenna 70 used for the measurement differs from the configuration shown in FIG. 6 in that the first auxiliary element 3 does not have the bent portion 3B (only the main body portion 3A) and has the second auxiliary element 4. No. The lengths of the other elements are the same as described above. In FIG. 7, the characteristic when the first auxiliary element 3 is provided is indicated by a solid line, and the characteristic when the first auxiliary element 3 is not provided is indicated by a broken line. The first auxiliary element 3 is a straight line with a length of 95 mm, and the length and arrangement of the other elements are as shown in FIG. According to FIG. 7, in the case where the first auxiliary element 3 is provided, the drop in gain on the low frequency side is small, and the average gain in the band is high.

  FIG. 8 shows a vertical polarization signal in the digital terrestrial TV broadcast band when the length of the main body 3A is changed when the bent portion 3B is provided in the first auxiliary element 3 in the antenna of the sixth embodiment. The gain (sensitivity) of the fourth antenna 70 is shown. In addition, the 4th antenna 70 used for the measurement does not have the 2nd auxiliary element 4 unlike the structure shown in FIG. The lengths of the other elements are the same as described above (for example, the length of the bent portion 3B is 45 mm). In FIG. 8, the characteristic when the length of the main body 3A is 50 mm is indicated by a solid line, the characteristic when it is 60 mm is indicated by a dotted line, the characteristic when 70 mm is indicated by a broken line, and the characteristic when it is 40 mm Is shown by a one-dot chain line. According to FIG. 8, when the length of the main body 3A is 50 to 60 mm, the drop in gain on the low frequency side is small and the average gain in the band is the highest.

  Further, by comparing the solid line in FIG. 7 and the solid line in FIG. 8, it is possible to know a change in characteristics in the digital terrestrial TV broadcast band depending on the presence or absence of the bent portion 3B of the first auxiliary element 3. According to this, when the bent portion 3B is provided (FIG. 8), the average sensitivity in the reception band is hardly changed, but the sensitivity on the low frequency side is improved and the sensitivity is flattened over the entire reception frequency.

  FIG. 9 shows the gain (sensitivity) of the fourth antenna 70 with respect to a vertically polarized signal in the terrestrial digital TV broadcast band when the position where the second auxiliary element 4 is connected to the main body 3A in the antenna of the sixth embodiment is changed. ). That is, FIG. 9 shows that the second auxiliary element 4 is connected to the main body portion 3A of the first auxiliary element 3 having the bent portion 3B or connected to the bending point (the connection point between the main body portion 3A and the bent portion 3B). It shows the difference in characteristics depending on whether or not. In FIG. 9, the characteristics when the upper second auxiliary element 4 is connected to a position 5 mm from the tip of the main body 3A (a position different from the connection position of the bent portion 3B) are indicated by solid lines, and the upper second auxiliary element is shown. The characteristic when 4 is connected to the tip of the main body 3A (the same position as the connection position of the bent portion 3B) is indicated by a dotted line. In any case, two second auxiliary elements 4 were provided, and the distance between them was 5 mm. According to FIG. 9, when the upper second auxiliary element 4 is connected to a position 5 mm from the tip of the main body 3 </ b> A, the drop in gain on the middle band side is small and the average gain in the band is high.

  FIG. 10 shows the gain (sensitivity) of the fourth antenna 70 with respect to a vertically polarized signal in the terrestrial digital TV broadcast band with and without the fourth auxiliary element 89 in the antenna of the sixth embodiment. In FIG. 10, the characteristic when the fourth auxiliary element 89 is provided is indicated by a solid line, and the characteristic when the fourth auxiliary element 89 is not provided is indicated by a broken line. According to FIG. 10, when the fourth auxiliary element 89 is provided, the drop in gain on the high frequency side is small, and the average gain in the band is high.

  Although the antenna sensitivity with respect to the vertically polarized signal has been described with reference to FIGS. 7 to 10, similarly, good antenna sensitivity with respect to the horizontally polarized wave was obtained.

  Although the present invention has been described in detail with reference to the accompanying drawings, the present invention is not limited to such specific configurations, and various modifications and equivalents within the spirit of the appended claims Includes configuration.

DESCRIPTION OF SYMBOLS 1 1st element 2 2nd element 3 1st auxiliary element 4 2nd auxiliary element 5 3rd auxiliary element 6 Feed part 10 1st antenna 50 2nd antenna 60 3rd antenna 70 4th antenna 81 Rear glass 82 Body flange 85 Connection line 86 Receiving amplifier 89 Fourth auxiliary element 90 Defogger 91 Heating line (horizontal line)
92 Vertical wire 93 Bus bar 94 Defogger coil 95 3rd feeding part 96, 97, 98 Auxiliary wire 99 Horizontal auxiliary wire 100 5th antenna

Claims (15)

A glass antenna disposed on a vehicle window glass,
A power feeding unit;
A first element extending in a predetermined direction from the power supply unit;
A second element extending from the power supply at a first predetermined angle with the first element;
A first auxiliary element connected to the first element or the second element at a second predetermined angle and disposed away from the other element;
A glass antenna comprising: at least one second auxiliary element connected to the middle or tip of the first auxiliary element. A glass antenna disposed on a vehicle window glass,
A power feeding unit;
A first element extending in a predetermined direction from the power supply unit;
A second element extending from the power supply at a first predetermined angle with the first element;
A first auxiliary element connected to the first element at a second predetermined angle and disposed away from the second element;
A glass antenna comprising: at least one third auxiliary element that is connected to the second element or the power feeding unit and extends to approach the first auxiliary element. A glass antenna disposed on a vehicle window glass,
A power feeding unit;
A first element extending in a predetermined direction from the power supply unit;
A second element extending from the power supply at a first predetermined angle with the first element;
A first auxiliary element connected to the first element or the second element at a second predetermined angle and disposed away from the other element,
A glass antenna, wherein at least one of a tip portion of the first element and a tip portion of the second element is bent. 4. The glass antenna according to claim 1, wherein the first auxiliary element is disposed substantially parallel to the other element at a distance of 30 mm or more. 5. The glass antenna according to claim 1 or 3 , wherein the first auxiliary element is disposed substantially parallel to the other element at a distance of 100 mm or more. The first element is an element extending in a substantially horizontal direction,
The glass antenna according to claim 1, wherein the first auxiliary element is connected to the first element and extends in a vertical direction.   The glass antenna according to claim 2, further comprising at least one second auxiliary element connected to the middle or the tip of the first auxiliary element. Two second auxiliary elements are provided,
One of the second auxiliary elements is connected in the middle of the first auxiliary element,
The glass antenna according to claim 1 or 7, wherein the other second auxiliary element is connected to a tip end of the first auxiliary element.   The glass antenna according to claim 1, further comprising at least one third auxiliary element connected to the other element or the power feeding unit. The first auxiliary element is connected to the first element;
The glass antenna according to claim 9, wherein the third auxiliary element is connected to the second element or the power feeding unit and extends to approach the first auxiliary element. The glass antenna is
An antenna for receiving a frequency band in which the wavelength of the center frequency is λ,
When the wavelength reduction rate of the window glass is α, the length of the first element extending in the horizontal direction is approximately 2αλ / 3, and the length of the second element extending in the vertical direction is approximately αλ / 3. The glass antenna according to any one of claims 1 to 10, wherein:   3. The glass antenna according to claim 1, wherein at least one of a front end portion of the first element and a front end portion of the second element is bent.   The glass according to any one of claims 1 to 12, wherein a defogger provided with a plurality of heating wires between a pair of bus bars and the pair of bus bars is disposed on the window glass. antenna. A second antenna is constituted by the heating wire of the defogger,
The glass antenna according to claim 13, wherein the power feeding unit of the second antenna is provided on a bus bar far from the power feeding unit to which the first element is connected. A fourth auxiliary element extending from the defogger bus bar;
The glass antenna according to claim 13 or 14, wherein the fourth auxiliary element is close to the first element, the second element, or the first auxiliary element and is capacitively coupled.

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