JP2009164678A - Glass antenna for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a glass antenna in which no-ground terrestrial digital TV antennas and AM-FM antennas are juxtaposed on an upper margin of a defogger of a rear window glass of a vehicle. <P>SOLUTION: The glass antenna includes hot side elements 10 having hot side and grounding side feeding points attached from the top on corners of longitudinal sides of the top margin and consisting of two first horizontal wires extending in a horizontal direction from the hot side feeding point toward the center line of the glass plate; and grounding side elements each comprising a first grounding element extending from the distal end of a first vertical wire extending in a horizontal direction from the grounding side feeding point 7 to near the hot side feeding point and provided with a second vertical wire above the distal end of the second horizontal wire close to the first horizontal wire of the hot side element, a second grounding element bent upward from the distal end of a third horizontal wire extending in a horizontal direction from the feeding point of grounding side and consisting of a third vertical wire provided closely to the second vertical wire and capacitively coupled thereto, and a third grounding element consisting of a vertical wire extending downward from the feeding point of the grounding side. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  In the present invention, an ungrounded terrestrial digital TV broadcast wave receiving antenna and an AM / FM radio antenna coexist in the upper margin of the defogger of a rear window glass for an automobile. The present invention relates to an antenna capable of obtaining high-sensitivity and stable reception performance in the same margin without reducing reception gain.

  Conventionally, an anti-fogging defogger is provided at the center of the rear window glass of an automobile to secure the rear view of the driver in rainy weather, and AM / FM radio broadcast waves are provided in the upper margin or lower margin. Many reception antennas and antennas for receiving television broadcast waves have been installed side by side.

  In recent years, television broadcast waves in Japan are shifting from terrestrial analog broadcasts of 90 to 220 MHz VHF band and 470 to 770 MHz UHF band to 470 to 710 MHz terrestrial digital broadcasts. It is becoming necessary to support digital terrestrial broadcasting for broadcasting radio wave transmission / reception equipment.

  For example, Japanese Patent Application Laid-Open No. 2006-197184 discloses a vehicle provided on a rear window glass plate equipped with an electrically heated defogger for a rear window of a vehicle. A glass antenna for a vehicle, wherein a plurality of defoggers are provided along a horizontal direction from a lower side to an upper side of the rear window glass plate, and a bus bar provided in a vertical direction on both right and left end sides of the rear window glass plate. A heater wire connecting between the bus bars, and having a high-frequency antenna conductor on at least one of the left and right ends of the rear window glass plate and above the defogger, The uppermost heater wire and the high-frequency antenna conductor are separated by 50 mm or more in the vertical direction of the rear window glass plate, and the uppermost heater wire is arranged in the horizontal direction of the rear window glass plate. A vehicle glass antenna characterized by having a branch heater wire that extends in the horizontal direction after branching upward from the rear window glass plate along at least one way from the end portion toward the center portion. (Patent Document 1).

  Further, as an example in which an antenna for a television broadcast wave and an antenna for an AM / FM radio broadcast wave are provided in the upper or lower margin of the defogger of the rear window glass of an automobile, for example, JP 2006-165933 A discloses a positive electrode. In a glass antenna for a vehicle that receives two antennas of non-grounded type with conductive wires extending from the feeding points of the negative electrode and the negative electrode on the same glass surface and receives diversity of the two antennas, 1 is provided on the glass plate surface. Two negative feed points and two positive feed points at positions near both sides thereof, the outer conductor antenna is extended from the negative feed point, and a central conductor antenna is disposed from each of the two positive feed points, A glass antenna for a vehicle, characterized in that the internal conductors of two coaxial cables are respectively connected to two positive feed points, and the two external conductors are connected to a negative feed point. It is mounting (Patent Document 2).

Further, for example, Japanese Patent Application Laid-Open No. 2007-53505 discloses an antenna made of conductive wire disposed on a window glass surface of a moving body such as an automobile or a surface of an insulating member of a body, and includes a first feeding point and a second feeding point. A loop element having a length of one to two wavelengths of a transmission / reception radio wave in which a feeding point is provided in the vicinity and a conductive wire is disposed from the first feeding point to the second feeding point, and any one of the feeding points On the other hand, a hot-side element having a length of ¼ wavelength to ¾ wavelength of a transmission / reception radio wave extended from one side, and 1/16 to ¼ extended by branching from the middle of the loop element to the outer side of the loop element. A vehicle antenna is described that is a loop antenna including a ground-side element having a wavelength length (Patent Document 3).
JP 2006-197184 A JP 2006-165933 A JP 2007-53505 A

  A high-frequency antenna such as a digital television provided on the left and right ends of the upper margin of the defogger shown in Patent Document 1, and an AM antenna and an FM antenna that are not grounded are provided at the center of the upper margin. However, digital TV antennas provided on the left and right ends of the upper margin are susceptible to radiated noise from the defogger if they are ungrounded. For this reason, the left and right corners on the upper side of the defogger are cut. The antenna performance may be degraded unless the vertical distance from the defogger is 50 mm or more apart.

  In addition, as already described, the non-grounded antenna as shown in Patent Document 2 has a plurality of coaxial cable terminals for connecting both the external conductor and the internal conductor of the coaxial cable to separate antennas. The total number of antennas increases and becomes complicated, and when multiple antennas are arranged in a limited space, the antennas are placed in close proximity to each other and adversely affect each other. There is a problem that the effect cannot be obtained, and when the antennas must be arranged at positions distant from each other, the core wire of the coaxial cable and the ground wire must be installed to each feeding point of the glass antenna. There was a problem.

  On the other hand, the ungrounded antenna pattern shown in Patent Document 3 is a glass antenna for UHF broadcast waves, which is a frequency for transmitting and receiving digital terrestrial broadcast waves, and the ground pattern has a loop shape. If the AM / FM radio broadcast wave receiving antenna is provided in the margin of the defogger because the area requires an area of about 100 mm × 100 mm, the reception performance of the terrestrial digital broadcast wave transmitting / receiving antenna is not degraded. There was a problem that it was difficult to form them side by side.

  In order to send and receive digital terrestrial broadcasting radio waves, it is necessary to use a highly sensitive ungrounded antenna compared to the case of transmitting and receiving terrestrial analog broadcast radio waves. Since the occupied area is larger than the antenna, there is a problem that it is difficult to coexist with the AM / FM radio broadcast wave receiving antenna provided in the margin part of the defogger of the rear window glass of the automobile, and the area is reduced. There was a need.

  The present invention has such a problem, that is, an AM / FM radio antenna pattern and an ungrounded terrestrial digital broadcast wave antenna are arranged in parallel in the upper margin of the defogger of a rear window glass for an automobile. In this case, the object is to make it difficult to receive radiation noise from the defogger and to obtain a stable reception gain without deteriorating the antenna performance.

  That is, the present invention relates to an antenna for a digital terrestrial television set provided in an upper margin of a defogger of a rear window glass of an automobile, and a hot-side feeding point and a ground-side feeding point from the upper side to the corner side of the vertical side portion of the upper margin. A hot-side element comprising two first horizontal filaments extending horizontally from the hot-side feeding point toward the center line side of the glass plate, and extending from the ground-side feeding point to the vicinity of the hot-side feeding point A first grounding element extending in a horizontal direction from the tip of the first vertical wire and having a second vertical wire above the tip of the second horizontal wire adjacent to the first horizontal wire of the hot side element; A third vertical line provided so as to be capacitively coupled with the second vertical line by bending upward from the tip of the third horizontal line extending in the horizontal direction from the feeding point on the side. 2 ground element, and a glass antenna for vehicles characterized by comprising a third earth element consisting of vertical strip which extends downward from the feeding point of the ground side.

  Alternatively, in the present invention, instead of the second vertical line, a branch line that branches from a middle portion of the second horizontal line of the first ground element near the ground-side feeding point is provided along the second horizontal line. In addition, in place of the third vertical line, a folded line that branches off from a middle part near the tip of the third horizontal line of the second ground element and folds back to the ground side feed point side is disposed. In the above-described glass antenna for a vehicle, the branch wire and the folded wire are brought close to each other and capacitively coupled.

  Alternatively, the present invention is the above-described glass antenna for vehicles, wherein a plurality of the third ground elements are arranged.

  Alternatively, the present invention is provided for a non-grounding type terrestrial digital television in each of two regions having vertical and horizontal sides of 50 to 100 mm on both the left and right corners on the upper end side of the upper margin of the defogger of the rear window glass of the automobile. The antenna for AM / FM radio comprising horizontal and vertical stripes that can be spaced apart from the terrestrial digital television antenna is provided in the remaining area of the upper margin excluding the two areas. The above-mentioned glass antenna for vehicles, wherein the antenna for digital terrestrial television and the antenna for AM / FM radio are separated and coexisted in the upper margin of the defogger.

  Alternatively, in the present invention, the AM / FM radio antenna is provided with a feeding point in the vicinity of the upper part of the bus bar on one side of the defogger, and from the tip of the crank element extended in a horizontal, vertical and horizontal crank shape from the feeding point. The vertical line extending in the vertical direction is connected to the vicinity of the middle point of the upper horizontal line part of the first U-shaped element, and below the middle point of the horizontal line on the lower side of the first U-shaped element. The extended vertical line is connected to the upper end of the second U-shaped element, and the middle point of the horizontal line on the upper side of the second U-shaped element is connected between the two terrestrial digital television antennas. In the above-described glass antenna for a vehicle, which is connected to the lower end of a vertical line extending downward from the middle point of the horizontal line along the upper side of the upper margin.

  Alternatively, in the present invention, the third horizontal line of the antenna for digital terrestrial television and the horizontal line on the upper side of the crank element of the antenna for AM / FM radio are at least 30 mm or more within the range of the upper margin. The above-described vehicle glass antenna is characterized in that it is spaced apart.

  Alternatively, in the present invention, either the central conductor or the outer conductor of the coaxial cable is connected to the hot-side feeding point of the antenna for the terrestrial digital television, and the other side of the coaxial cable is connected to the ground-side feeding point. The glass antenna for a vehicle according to any one of the above-described features.

  According to the present invention, it is possible to reduce the area of an ungrounded terrestrial digital broadcast wave antenna provided in the upper margin of the defogger of the rear window glass of the automobile. Terrestrial digital broadcast wave antennas and AM / FM radio antenna patterns can be juxtaposed in a narrow upper margin with a limited number of antennas, and variations in reception gain of each antenna are improved. Even if an antenna pattern for AM and an antenna pattern for AM / FM radio are arranged side by side, it becomes difficult to receive radiation noise from the defogger, and a stable reception gain with high sensitivity can be obtained without deteriorating the antenna performance. It was.

  As shown in FIG. 1, the present invention provides a terrestrial digital broadcast wave antenna 5 on a rear window glass 1 of an automobile, and the terrestrial digital broadcast is provided in a narrow area on the indoor surface of the upper margin of the defogger 3. The wave antenna 5 and the AM / FM radio antenna 30 can be juxtaposed.

  As shown in FIG. 1, the terrestrial digital TV antenna 5 is a non-grounded antenna in which two elements, a hot-side hot element 10 and a ground-side earth element 20, are combined. One antenna is arranged in each of two regions of about 50 to 100 mm on each side of the left and right corners on the upper end side of the upper margin of the defogger 3.

  The hot-side element 10 is extended from the hot-side feeding point 6 provided on the upper side of the left and right corners of the upper margin part toward the center line that is the center of the left and right sides of the glass plate 1 in the horizontal direction. It consists of one horizontal filament 11,11. The two first horizontal filaments 11 and 11 have substantially the same length and are provided close to each other.

  On the other hand, the earth-side element 20 on the earth side extends from the earth-side feeding point 7 provided below the hot-side feeding point 6 to the hot-side feeding point 6 side and then approaches along the first horizontal line on the hot side. The first earthing element 21 provided in this manner, the second earthing element 22 extending in the horizontal direction from the earthing-side feeding point 7, and the third earthing element 23 extending in the fourth direction on the lower side extend in three directions. It consists of three lines.

  As shown in FIG. 4, the first ground element 21 that extends upward from the ground-side feeding point 7 has a first vertical line 21 a that extends from the ground-side feeding point 7 to the vicinity of the hot-side feeding point 6. A second horizontal line 21b extending from the tip of the first vertical line 21a so as to be close to the first horizontal line 11 of the hot-side element 10, and extending upward from the tip of the second horizontal line 21b. It consists of the 2nd vertical filament 21c. In this case, the second vertical filament 21c and the first horizontal filament 11 of the hot-side element 10 are disposed at a position where they do not intersect.

  Further, as shown in FIG. 5, the first ground element 21 is replaced with the second vertical wire 21c (see FIG. 4), and the ground-side power feeding of the second horizontal wire 21b of the first ground element 21 is performed. A branch line 21d consisting of a vertical line branching from the middle part near point 7 and a horizontal line extending from the vertical line in the horizontal direction substantially coincides with the tip of the second horizontal line along the second horizontal line. You may make it arrange | position by length.

  On the other hand, as shown in FIG. 4, a third vertical filament 22b extending in the horizontal direction from the ground-side feeding point 7 toward the center of the glass plate 1 and extending upward from the tip of the third horizontal filament 22a. The third vertical wire 22b and the second vertical wire 21c of the first ground element 21 are brought close to each other and capacitively coupled.

  Further, as shown in FIG. 5, the second ground element 22 branches from a middle portion of the second ground element 22 near the tip of the third horizontal line 22 a instead of the third vertical line. Further, a folded wire 22c that is folded back to the ground-side feeding point 7 side can be provided. In this case, the branch line 21d and the folded line 22c may be brought close to each other and capacitively coupled.

  The third ground element 23 is a fourth vertical line extending downward from the ground-side feeding point 7. However, if a plurality of the third ground elements 23 are arranged, the receiving sensitivity is further improved. preferable.

  As shown in FIG. 1, an ungrounded terrestrial digital TV antenna 5 composed of the hot side element 10 and the ground side element 20 is arranged at the upper end side of the upper margin of the defogger 2 of the rear window glass 1 of the automobile. Diversity reception was performed by providing each of the two regions of 50 to 100 mm on each side of the left and right corners.

  In addition, either the central conductor or the outer conductor of the coaxial cable is connected to the hot-side feeding point of the antenna for the digital terrestrial television, and the other side of the coaxial cable is connected to the ground-side feeding point. I made it.

  As shown in FIGS. 1 and 2, the pattern of the terrestrial digital TV antenna 5 can be made smaller than the conventional terrestrial digital TV antenna pattern as shown in FIG. The antenna pattern 30 for AM / FM radio that can be separated from the terrestrial digital TV antenna 5 can be disposed in the remaining area of the upper margin excluding the two areas for the TV antenna 5, The digital TV antenna 5 and the AM / FM radio broadcast wave antenna 30 can coexist in the upper margin of the defogger 2.

  The AM / FM radio broadcast wave antenna 30 is provided with a feeding point 31 in the vicinity of the upper portion of the bus bar 4 'on one side of the defogger 3, and a crank element having a horizontal line and a vertical line extending from the feeding point 31 into a crank shape. A vertical line 34 extending vertically from the tip of 32 is connected to the vicinity of the middle point of the upper horizontal line portion of the first U-shaped element 33, and the lower horizontal line of the first U-shaped element 33 is connected. A vertical line 34 ′ extending downward from the middle point of the line was connected to the upper end of the second U-shaped element 35.

  Furthermore, a vertical line extending from the vicinity of the middle point of the horizontal line on the upper side of the second U-shaped element 35 toward the upper side of the rear window glass 1, and both left and right directions from the tip along the upper side of the rear window glass It consists of the T-shaped element 36 extended in this.

  Furthermore, the FM broadcast wave sub-antenna 40 provided in the lower margin of the defogger 3 is diversity-received with the AM / FM radio antenna 30 to improve the directivity by the diversity effect at the time of FM broadcast wave reception. Is provided.

  The third horizontal line 22a of the terrestrial digital TV antenna 5 and the horizontal line on the upper side of the crank element 32 of the AM / FM radio antenna 30 are separated by at least 30 mm within the range of the upper margin. Is good.

  Each horizontal line and vertical line of the digital terrestrial TV antenna 5 and the AM / FM radio antenna 30 of the present invention is preferably provided at least 5 to 15 mm away from the inside of the flange of each window. This is because when the antenna of the present invention is close to the body, the received radio wave is prevented from leaking by the body and the reception gain is reduced.

  Furthermore, when the length of the first horizontal filament 11 of the hot side element 10 is set to 1 / 4αλ to 3 / 4αλ (α: wavelength shortening rate of glass, λ: wavelength of received radio wave), the reception state is improved. In addition, the frequency characteristic is flat, which is preferable.

  The operation of the present invention will be described below.

  The reason why the hot-side element 10 and the ground-side element 20 of the terrestrial digital TV antenna 5 of the present invention are separated from the inside of the opening of the window frame flange 60 by 5 to 15 mm is not affected by the metal body of the automobile. However, it is desirable to separate the terrestrial digital TV antenna 5 from the hot-side feed point 6 and the ground-side feed point 7 from the window frame flange 60. If it is moved too far to the inside of the plane, interference will easily occur due to the effects of the AM / FM radio antenna 30 and the defogger 3, and the coaxial cable that feeds the hot-side feed point 6 and the ground-side feed point 7 This is because a new problem such as the conspicuous wiring occurs.

  In addition, by providing the first horizontal filament 11 of the hot-side element 10 of the terrestrial digital TV antenna 5, the frequency characteristic curve becomes flat, and the reception sensitivity of the antenna can be greatly improved.

  The third horizontal line 22a of the terrestrial digital TV antenna 5 and the horizontal line on the upper side of the crank element 32 of the AM / FM radio antenna 30 are separated by at least 30 mm within the range of the upper margin. The reason is that, when approaching less than 30 mm, the terrestrial digital TV antenna 5 and the AM / FM radio antenna 30 interfere with each other, and the UHF band radio wave received by the terrestrial digital TV antenna 5 may leak. Because there is.

  If the vertical spacing is too wide, the terrestrial digital TV antenna 5 and the AM / FM radio antenna 30 cannot be arranged in the upper margin.

  The reason why the ground side element 20 is provided with various horizontal and vertical stripes is to improve the reception sensitivity of the terrestrial digital TV antenna 5. On the other hand, the reason why no vertical filament is provided from the hot-side feeding point 6 of the hot-side element 10 that is the hot side is to avoid interference with the second horizontal filament at the uppermost position of the AM / FM radio antenna 30. It is.

  In the case of FIG. 1 in which the second vertical line 21c of the first earth element 21 of the earth side element 20 and the third vertical line 22b of the second earth element 22 are provided, the second horizontal line 21b, 3 The terrestrial digital TV antenna 5 has a vertically bent pattern compared to the case where the horizontal wires 22a are bent vertically upward from the tip of the horizontal wires 22a but are not extended vertically by bending both wires. This has the advantage that the receiving sensitivity is superior and the area occupied by the antenna is reduced.

  On the other hand, the AM / FM radio antenna 30 is juxtaposed with the space between the terrestrial digital TV antenna 5 and the terrestrial digital TV antenna 5 disposed at both upper corners of the upper margin of the defogger being 30 mm apart. In order to achieve this, the lengths of the vertical stripes of the first U-shaped element 33 and the second U-shaped element 35 of the AM / FM radio antenna 30 and the vertical stripes 34 and 34 'connecting them are described. The length was adjusted, and the two antennas were juxtaposed at intervals that do not interfere with each other. Of course, this is usually applied to the rear window glass of the general passenger car class.

  Examples of the present invention will be described below.

[Example 1]
The terrestrial digital TV antennas 5 and 5 comprising two elements, a hot-side element 10 and a ground-side element 20, at the left and right corners of the upper margin of the defogger 3 of the rear window glass 1 of the automobile as shown in FIG. Is disposed.

  As shown in FIG. 4, the hot side element 10 is horizontally oriented from the hot side feeding point 6 provided on the left and right corners of the upper margin part toward the center line side that is the center of the left and right sides of the glass plate 1. The two first horizontal filaments 11, 11 extending in the same manner, and the two first horizontal filaments 11, 11 are substantially the same length and are provided close to each other.

  The ground side element 20 includes a first ground element 21, a second ground element 22 connected to a ground side feed point 7 provided below the hot side feed point 6, and a third ground element 23 extending downward. It consists of three filaments.

  The first ground element 21 includes a first vertical line 21a extending from the ground side feed point 7 to the vicinity of the hot side feed point 6, and a first vertical line 21a extending from the tip of the first vertical line 21a. It consists of the 2nd horizontal filament 21b extended so that it might adjoin to the 1 horizontal filament 11, and the 2nd vertical filament 21c extended upwards from the front-end | tip.

  The second ground element 22 is adjacent to the second horizontal line 21c of the first ground element 21 from the third horizontal line 22a extending in the horizontal direction from the ground-side feeding point 7 and the tip of the horizontal line 22a. And the third vertical filament 22b extending upward.

Further, the AM / FM main antenna 30 includes a first U-shaped element 33 having a vertical line 34 extending in a vertical direction from a tip of a crank element 32 having a horizontal line and a vertical line extending in a crank shape from a feeding point 31. A vertical line 34 ′ connected to the vicinity of the midpoint of the upper horizontal line portion of the first horizontal line section and extending downward from the midpoint of the lower horizontal line of the first U-shaped element 33 is a second U-shaped element. It connected with the front-end | tip part of 35 upper side.
Furthermore, a vertical line extending from the vicinity of the middle point of the horizontal line on the upper side of the second U-shaped element 35 toward the upper side of the rear window glass 1, and both left and right directions from the tip along the upper side of the rear window glass It consists of the T-shaped element 36 extended in this.

The dimensions of the window glass plate 1 are: upper side = 1150 mm, lower side = 1250 mm, side side = 750 mm
The length of each filament at the left corner of the terrestrial digital TV antenna 5 is as follows.

The length of the two first horizontal filaments 11, 11 of the hot side element 10 = 50 mm,
The distance between the two first horizontal filaments 11, 11 = 5 mm,
Length of first vertical filament 21a of first ground element 21 of ground side element 20 = 35 mm
Length of second horizontal filament 21b = 60 mm
Length of second vertical filament 21c = 30 mm
The length of the third horizontal filament 22a of the second ground element 22 = 70 mm
The length of the third vertical filament 22b = 70 mm
The length of the three fourth vertical filaments of the third earth element 23 = 55 mm each
The distance between the first horizontal line 11 on the lower side and the second horizontal line 21b of the first ground element 21 = 5 mm,
The distance between the second vertical line 21c of the first ground element 21 and the third vertical line 22b of the second ground element 22 = 5 mm
The hot-side feeding point 6 and the first horizontal filament 21 are positioned 60 mm away from the top side of the glass, and the ground-side feeding point 7 and the third grounding element 23 are located 90 mm away from the vertical opening side of the flange. .

  On the other hand, as shown in FIG. 1, the AM / FM radio broadcast wave antenna 30 is provided with a feeding point 31 in the vicinity of the upper portion of the bus bar 4 on one side of the defogger 3.

The length of the horizontal filament 32a of the crank element 32 = 60 mm,
The length of the vertical filament 32b = 70 mm,
Length of horizontal filament 32c = 250mm
The length of the horizontal filament 33a of the first U-shaped element 33 = 450 mm,
The length of the vertical filament 33b = 20 mm,
Length of horizontal filament 35a of second U-shaped element 35 = 1000 mm
The length of the vertical filament 35b = 20 mm,
The length of the horizontal filament 36a of the T-shaped element 36 = 900 mm,
Length of vertical filament 36b = 140mm
The antenna is printed at a predetermined position on the indoor side of the window glass plate with a conductive paste at a width of 0.7 mm, dried, and baked in a heating bending furnace.

  Further, the central conductor of the coaxial cable extended from a tuner (not shown) is connected to the hot-side feeding point 6, and the outer conductor is connected to the ground-side feeding point 7. Similarly, the AM / FM main antenna is extended from the tuner (not shown). The central conductor of the coaxial cable was connected to the feeding point 31.

  The terrestrial digital television broadcast wave antennas 5 of the first embodiment are arranged one by one on the left and right as antennas in the terrestrial digital television broadcast wave band having a frequency of 470 to 710 MHz, and receive diversity. In addition, according to the present invention, the terrestrial digital TV broadcast wave antenna and the AM / FM broadcast wave main antenna arranged in parallel in the upper margin of the defogger of the rear window glass of the automobile can reduce the area of the conventional antenna. Receiving sensitivity comparable to that of an antenna was obtained, and it was sufficiently practical.

The main maximum width of the area occupied by the terrestrial digital TV antenna 5 of the first embodiment is 82 mm, and the height direction except for the third ground element 23 that hardly affects the occupied area along the side portion. The main maximum height is 70 mm. When compared with the maximum width 145 mm and the maximum height 145 mm of the terrestrial digital TV antenna pattern 5 ′ of Comparative Example 1, the occupied area can be reduced by about 70%.
[Example 2]
The second embodiment shown in FIGS. 2 and 5 does not have the second vertical wire 21c (see FIG. 4) in comparison with the ground side element 20 of the first embodiment shown in FIGS. A branch line 21d that branches from a middle portion of the second horizontal line 21b of the first ground element 21 near the ground-side feeding point 7 is disposed along the second horizontal line.

  Further, instead of the third vertical line 22b shown in FIG. 4, as shown in FIG. 5, the second ground element 22 branches off from a middle part near the tip of the third horizontal line 22a and is on the ground side feeding point 7 side. Folded wire strips 22c that are folded back are arranged so that the branched wire strips 21d and the folded wire strips 22c are brought close to each other and capacitively coupled. Others are the same as in the first embodiment.

The length of each line of the terrestrial digital TV antenna 5 in FIG.
The length of the second horizontal filament 21b of the first ground element 21 of the ground side element 20 = 80 mm
Length of branch line 21d = 55mm
Length of the third horizontal filament 22a of the second ground element 22 = 85 mm
Length of folded wire 22c = 55mm
The length of the vertical line from the branch point of the second horizontal line 21b to the branch line 21d = 20 mm
The distance between the third horizontal filament 22a and the folded filament 22c = 10 mm
The other filaments are the same as in Example 1.

  The main maximum width of the area occupied by the terrestrial digital TV antenna 5 of the second embodiment is 97 mm, and the height direction is the main except for the third earth element 23 that hardly affects the occupied area along the side portion. The maximum height is 55 mm. As in Example 1, Example 2 was able to reduce the occupied area of the terrestrial digital TV antenna 5 by about 70% compared to Comparative Example 1.

  Each antenna is printed with a conductive paste at a predetermined position on the indoor side of the window glass plate with a width of 0.7 mm, dried, and baked in a heating bending furnace.

  Further, the central conductor 2a of the coaxial cable 2 extending from a tuner (not shown) is connected to the hot-side feeding point 6, and the outer conductor 2b is connected to the grounding-side feeding point 7, and similarly the AM / FM main antenna is not shown. The central conductor of the coaxial cable extending from the tuner was connected to the feeding point 31.

  The terrestrial digital television broadcast wave antennas 5 and 5 of the second embodiment are arranged one by one on the left and right as antennas in the terrestrial digital television broadcast wave band having a frequency of 470 to 710 MHz, and receive diversity.

  The terrestrial digital television broadcast wave antennas 5 and 5 and the AM / FM broadcast wave main antenna 30 arranged in parallel in the upper margin of the defogger 3 of the rear window glass 1 of the automobile according to the present invention are described in Comparative Example 1 of FIG. Compared to the conventional terrestrial digital television broadcast wave antennas 5 'and 5', the area can be reduced, and compared with the conventional terrestrial digital television broadcast wave antennas 5 'and 5'. Receiving sensitivity was obtained, and it was sufficiently practical.

[Comparative Example 1]
A pair of conventional terrestrial digital television broadcast wave antennas 5 'and 5' shown in FIG. 3 are provided at the left and right corners of the upper margin of the defogger 3 of the rear window glass 1 of the automobile and receive diversity.

  The terrestrial digital television broadcast wave antennas 5 'and 5' are non-grounded antennas each having an element extending from two feeding points, and a loop-shaped ground side element is provided so as to surround the hot side element. ing.

  The ground-side element has a rectangular loop shape, and the main maximum width and maximum height are 145 mm each, except for the line protruding in the horizontal direction from the loop line.

  In the comparative example shown in FIG. 3, a space for providing an AM / FM antenna cannot be secured in the area of the upper margin of the defogger, and only a pair of terrestrial digital television broadcast wave antennas 5 ′ and 5 ′ are provided. Pattern.

  As mentioned above, although demonstrated by the preferable Example, this invention is not limited to these, A various application is possible.

The whole figure of the rear window glass of Example 1 of the present invention. The whole figure of the rear window glass of Example 2 of the present invention. The whole figure of the rear window glass which provided the antenna for conventional terrestrial digital. 1 is an enlarged view of a terrestrial digital antenna according to Embodiment 1 of the present invention. FIG. The enlarged view of the antenna for terrestrial digital of Example 2 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Window glass 3 Defogger 3a Horizontal heating wire 3b Vertical wire 4, 4 'Bus bar 5 Terrestrial digital TV antenna 6 Hot side feed point 7 Ground side feed point 10 Hot side element 11 1st horizontal wire 20 2nd element 21 First ground element 21a First vertical line 21b Second horizontal line 21c Second vertical line 21d Branch line 22 Second ground element 22a Third horizontal line 22b Third vertical line 22c Folded line 23 Third ground element 23a Fourth vertical line 30 FM broadcast wave main antenna 31 Feed point 32 Crank element 33 First U-shaped element 35 Second U-shaped element 36 T-shaped element 40 FM broadcast wave sub-antenna

Claims (7)

In the terrestrial digital television antenna provided in the upper margin of the defogger of the rear window glass of the automobile, a hot-side feeding point and a ground-side feeding point are provided on the corner side of the vertical side portion of the upper margin from the upper side. A hot-side element composed of two first horizontal filaments extending horizontally from the feeding point toward the center line side of the glass plate;
Extending horizontally from the tip of the first vertical filament extending from the ground-side feeding point to the vicinity of the hot-side feeding point, and second above the tip of the second horizontal filament adjacent to the first horizontal filament of the hot-side element. A first ground element provided with a vertical line, and bent upward from the tip of a third horizontal line extending in the horizontal direction from the power supply point on the ground side so as to be close to the second vertical line and capacitively coupled. A ground side element composed of a second ground element composed of a third vertical line, and a third ground element composed of a vertical line extending downward from the ground side feeding point;
The glass antenna for vehicles characterized by comprising. Instead of the second vertical line, a branch line that branches from a middle portion of the second horizontal line of the first ground element near the ground-side feeding point is disposed along the second horizontal line, and In place of the three vertical wires, a folding wire is provided that branches from a middle portion near the tip of the third horizontal wire of the second ground element and folds back to the ground feeding point side. The glass antenna for a vehicle according to claim 1, wherein the wire is close and capacitively coupled. The glass antenna for a vehicle according to claim 1 or 2, wherein a plurality of the third ground elements are arranged. The antenna for terrestrial digital television of the non-grounding type is provided in each of two regions of 50-100 mm in each side of the left and right corners on the upper end side of the upper margin of the upper margin of the rear window glass of the automobile, The remaining area of the upper margin excluding the two areas is provided with an antenna for AM / FM radio composed of horizontal and vertical stripes that can be spaced apart from the antenna for terrestrial digital television. The glass antenna for a vehicle according to any one of claims 1 to 3, wherein the antenna and the antenna for the AM / FM radio are arranged separately in the upper margin of the defogger. The AM / FM radio antenna is provided with a feeding point in the vicinity of the upper part of the bus bar on one side of the defogger, and a vertical line extending in the vertical direction from the tip of the crank element extending in a horizontal, vertical and horizontal crank shape from the feeding point. A vertical line extending below the midpoint of the horizontal line on the lower side of the first U-shaped element is connected to the vicinity of the midpoint of the upper horizontal line section of the first U-shaped element. Connected to the top end of the upper U-shaped element of the second U-shaped element, and in the vicinity of the middle point of the upper horizontal line of the second U-shaped element along the upper side of the upper margin between the two terrestrial digital television antennas. 5. The glass antenna for a vehicle according to claim 4, wherein the glass antenna is connected to a lower end of a vertical line extending downward from a middle point of the horizontal line. The third horizontal stripe of the antenna for digital terrestrial television and the horizontal stripe on the upper side of the crank element of the antenna for AM / FM radio are separated from each other by at least 30 mm within the range of the upper margin. The glass antenna for vehicles according to claim 4 or 5 characterized by things. A center conductor of the coaxial cable or an outer conductor is connected to the hot-side feeding point of the antenna for the terrestrial digital television, and the other side of the coaxial cable is connected to the ground-side feeding point. The glass antenna for vehicles according to any one of claims 1 to 6.

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