JP3084548U - Adhesive film antenna - Google Patents

Abstract

(57) [Summary] In a pasting-type film antenna, the film antenna is downsized while maintaining high reception sensitivity, and the pasting operation is facilitated. A sticking type film antenna (10),
A first antenna element 4 formed at a corner of the base film 2 and connected to the first feeding point 6 in a loop shape, formed on the base film 2 and formed in a pole shape,
After temporarily extending from the second feeding point 9 provided adjacent to the first feeding point 6 to the side opposite to the first antenna element 4, it bends in a U-shape, and its end is the first A second antenna element arranged close to the antenna element, a first opening provided in the base film portion surrounded by the loop-shaped first antenna element, and a loop-shaped first antenna; It has a second opening 14 provided in the base film portion surrounded by the first antenna element 4 and the second antenna element 8 outside the element 4.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention relates to a sticking type film antenna used by sticking to a window glass of a vehicle or the like.

[0002]

[Prior art]

 2. Description of the Related Art Among pasting-type film antennas that are used by being pasted on a front window glass of a vehicle, various antennas are known which ensure the visibility of a vehicle driver and ensure reception performance. For example, in a loop antenna described in JP-A-9-130124 or JP-A-2000-77922, one antenna element is provided on one film to perform vehicle verification and periodic point verification. By adopting an antenna shape that matches the shape of the seal attached to the front window, we have proposed an antenna with high reception sensitivity while ensuring the driver's view.

[0003]

[Problems to be solved by the invention]

 However, in recent years, in addition to radio (FM and AM broadcasting), TV (UHF band and VHF band) broadcasting radio waves, VICS (Vehicle Information Communication System: Vehicle Information Communication System), and the like have been provided to vehicles. Antennas are being installed, and these radio waves are used in different frequency bands. In particular, TV broadcast radio waves use a considerably wide frequency band, so one antenna covers all frequency bands. I can't.

[0004] For this reason, in order to cover all frequency bands, a plurality of antennas suitable for radio waves in each frequency band must be provided on a windshield. According to the configuration in which one antenna element is provided on one film, the cost is increased by installing a plurality of antennas, the assembling work is increased, the visibility of the driver is deteriorated, and the appearance is not preferable. was there.

[0005] The present invention has been made in view of such a point, and it is an object of the present invention to make it possible for each antenna element to maintain a high receiving sensitivity without deteriorating performance due to mutual interference and to improve film sensitivity. The present invention proposes a pasting-type film antenna that can reduce the size of the antenna, thereby reducing the cost per antenna element, simplifying the assembling work, securing the driver's view, and improving the appearance. It is.

[0006]

[Means for Solving the Problems]

 In order to solve the above-mentioned problem, a sticking type film antenna according to the first configuration of the present invention is a sticking type film antenna for sticking an antenna element to a non-conductive material and receiving a radio wave of a desired wavelength, A first antenna element formed at a corner, formed in a loop shape and connected to the first feeding point, formed on the base film, formed in a pole shape, and provided adjacent to the first feeding point; After temporarily extending from the second feeding point to the side opposite to the first antenna element, the antenna is bent in a U-shape, and the end of the second antenna element is disposed in close proximity to the first antenna element. A first opening provided to penetrate the base film in the base film portion surrounded by the first antenna element having a loop shape, and an outer portion of the first antenna element having the loop shape. To the base film portion surrounded by the first antenna element and the second antenna element, having a second opening, which is provided so as to penetrate the base film.

According to the above configuration, each antenna element is reduced in size while maintaining high reception sensitivity without deteriorating performance due to mutual interference, thereby reducing the cost per antenna element. At the same time, each finger of one hand can be inserted into each of the first opening and the second opening, and the film antenna can be held with one hand. Pasting work can be done without touching.

[0008] In the pasting type film antenna according to the second configuration of the present invention, the first opening and the second opening are arranged side by side, and the second antenna element is disposed near the end thereof. The base film portion disposed along the first antenna element and surrounded by the first antenna element and the second antenna element outside the loop-shaped first antenna element, and extending downward from the first opening. And a third opening provided to penetrate the base film.

According to the above configuration, the portion where the antenna element of the base film is not disposed is set as the opening, so that the cost due to weight reduction and material reduction is reduced, and the first opening is reduced. Each finger of one hand can be inserted into the third opening in addition to each opening of the second opening, and the film antenna can be more easily held with one hand. This enables the sticking operation without touching the adhesive coated surface.

[0010] In the pasting-type film antenna according to the third configuration of the present invention, the peripheral portion of the first opening and the peripheral portion of the third opening are respectively located at a portion closest to the second opening. Straight portions are arranged in the base film so as to be linear, and the peripheral portion of the second opening is the first opening at a portion closest to the first opening. It has a straight portion parallel to each of the above-mentioned straight portions in the peripheral portion of one opening and the peripheral portion of the third opening.

[0011] According to the above configuration, it is easy to insert each finger of one hand into each of the first opening and the second opening, and the pasting-type film antenna can be appropriately moved vertically. When the above-mentioned film antenna is held with one hand, the above-mentioned pasted film antenna does not bend in the vertical direction, and the pasted film antenna is held with one hand without touching the adhesive-coated surface. Since all pasting operations can be performed, the assembling operation can be facilitated.

[0012] In the pasting-type film antenna according to the fourth configuration of the present invention, the first antenna element and the second antenna element are provided in a base film portion sandwiched between the second opening and the third opening. Are not formed.

According to the above configuration, by providing the base film portion on which neither the first antenna element nor the second antenna element is formed, in a region sandwiched between the second opening and the third opening. The pasting-type film antenna will have appropriate strength in the vertical direction, and when holding the film antenna with one hand, the pasting-type film antenna will not bend in the vertical direction and touch the adhesive coated surface. This makes it possible to hold the sticking film antenna with one hand, making it easier to assemble it.

A fifth aspect of the present invention provides a pasting type film antenna, comprising: a distance Ld between a peripheral edge of the first opening and a peripheral edge of the second opening; and a peripheral edge of the first opening. The distance Le at the closest portion between the portion and the peripheral portion of the third opening is configured to satisfy Le <Ld.

According to the above configuration, the pasting-type film antenna has an appropriate strength in the vertical direction, and each finger of one hand is inserted into the first opening and the second opening. When the film antenna is held with one hand, the sticking type film antenna does not bend in the vertical direction, and the sticking operation can be performed by holding the film antenna with one hand without touching the adhesive coated surface.

According to a sixth aspect of the present invention, there is provided a pasting type film antenna comprising: a distance Lf between a periphery of the third opening and a periphery of the second opening; The distance Ld at the closest part between the peripheral part and the peripheral part of the second opening and the distance Le at the closest part between the peripheral part of the first opening and the peripheral part of the third opening are Le <Lf. , And Le <Ld.

According to the above configuration, the pasting-type film antenna has an appropriate strength in the up-down direction, and each finger of one hand is inserted into the third opening and the second opening. When the film antenna is held with one hand, the sticking type film antenna does not bend in the vertical direction, and the sticking operation can be performed by holding the film antenna with one hand without touching the adhesive coated surface.

The adhesive film antenna according to the seventh aspect of the present invention is configured such that the Ld satisfies 5 mm ≦ Ld ≦ 120 mm.

According to the above configuration, the pasting-type film antenna has an appropriate strength in the vertical direction, and it is possible to prevent the film antenna from bending in the vertical direction when holding the film antenna with one hand.

The adhesive film antenna according to the eighth configuration of the present invention is configured such that Lf satisfies 5 mm ≦ Lf ≦ 120 mm.

According to the above configuration, the pasting-type film antenna has an appropriate strength in the vertical direction, and it is possible to prevent the film antenna from bending in the vertical direction when the film antenna is held with one hand.

[0022]

[Effect of the invention]

 According to the present invention, each antenna element is reduced in size while maintaining high reception sensitivity without deteriorating performance due to mutual interference, thereby reducing the cost per antenna element. This facilitates the assembly work, secures the driver's view, and improves the appearance.

[0023]

[Embodiment of the invention]

 Hereinafter, the configuration of the sticking type film antenna of the present invention, the sticking method, and the receiving performance when applied to the front window glass of a vehicle will be described with reference to the drawings. First, the configuration of the adhesive film antenna will be described.

<Structure of Adhesive Film Antenna> As shown in FIG. 1, the adhesive film antenna 10 of the present invention is provided on a base film 2 made of a rectangular non-conductive material and on the base film 2. A first antenna element 4 having a rectangular loop shape, a first feed point 6 for connecting the first antenna element 4 to a feed line, a second antenna element 8 having a pole shape, and a second antenna element 8 And a second power supply point 9 for connecting the power supply line.

Further, the film in the region surrounded by the rectangular loop of the first antenna element 4 has a first opening 12, and the film in the region surrounded by the first antenna element 4 and the second antenna element 8 has The second openings 14 are provided so as to be juxtaposed in the lateral direction of the first openings 12. Further, a third opening 16 is provided in the film below the first opening 12 and surrounded by the first antenna element 4 and the second antenna element 8.

The first antenna element 4 uses a rectangular loop-shaped antenna so as to be suitable for receiving a wide first frequency band at a relatively high frequency such as 4CH to 12CH of TV and UHF of TV. On the other hand, as the second antenna element 8, a pole-shaped antenna is used so as to be suitable for receiving a narrow second frequency band at a relatively low frequency such as FM radio, VICS, and TV 1CH to 3CH.

In the rectangular loop shape of the first antenna element 4, the vertical length L1y is determined by L1y ≦ α · λ / 4, where λ is the wavelength of the receiving frequency and α is the wavelength shortening rate of glass. In the embodiment shown in FIG. 1, L1y = 65 mm, the lateral length L1x is determined by L1x ≦ 60 cm−L1y, and in the embodiment shown in FIG. 1, L1x = 150 mm. On the other hand, the total pole length L2 of the second antenna element 8 (here, L2 = L21 + L22 + L23) is determined by L2 ≦ α · λ / 4, and in the embodiment shown in FIG. 1, L2 = 485 mm.

On the other hand, the maximum distance L22 in the vertical direction of the antenna pattern provided on the base film 2 secures a driver's view at a conventional level when the above-mentioned adhesive film antenna is attached to the front window glass of a vehicle. Is determined by

That is, conventionally, when the antenna element of the pasting-type film antenna is attached to the front windshield 100 of the vehicle, as shown by the hatched portion in FIG. It is necessary to fit within 100 mm from the upper end of the front window glass 100. For this reason, the maximum vertical separation distance L22 of the antenna pattern needs to be 100 mm or less, and in the embodiment shown in FIG. 1, L22 = 100 mm.

Further, as shown by the hatched portion in FIG. 2, the maximum width Lmax of the base film 2 is attached to the vehicle windshield 100, the vehicle verification seal 19, the periodic point verification seal 18, In addition, considering the space for two sticking-type film antennas 10 according to the present invention arranged in the horizontal direction, and considering the space for resealing these seals, it is necessary to set the width to 335 mm or less. In the embodiment, Lmax = 335 mm.

When the film antenna 10 is attached to the front window glass 100 of the vehicle, the first antenna element 4 and the second antenna element 8 lower the sunvisor (not shown), thereby Similarly, the first power supply point 6 and the second power supply point 8 are arranged so as to be shielded when the sun visor is lowered, as viewed from the vehicle interior. In this way, the driver's view of the conventional level can be secured.

Next, the layout of each antenna element on the base film 2 will be described. As shown in FIG. 1, a first antenna element 4 is formed at the upper right corner of the base film 2 to form a loop shape. Thus, it is connected to a first feeding point 6 provided at the center of the upper side of the base film 2.

Further, the second antenna element 8 is formed in a pole shape, and approaches the first feeding point 6 from the second feeding point 9 located at the center of the upper side of the base film 2. After temporarily extending to the side opposite to the antenna element 4 (L21 part in FIG. 1), after extending along the left vertical side of the base film 2 (L22 part in FIG. 1) to form a U-shape. The base film 2 extends along the lower side of the base film 2 (portion L23 in FIG. 1), and the terminal end thereof is arranged so as to be close to the first antenna element 4.

The arrangement and layout are such that the distance between the first antenna element 4 and the second antenna element 8 is always larger than the distance between the second feed point 9 and the first antenna element 4. .

On the other hand, in the base film 2, as shown in FIG. 1, a first opening 12 penetrating the base film 2 is provided in a portion surrounded by the loop-shaped first antenna element 4, and the loop Outside the first antenna element 4 having the shape, a second opening penetrating the base film 2 is provided in a portion on the left side of the first opening 12 and surrounded by the first antenna element 4 and the second antenna element 8. The base film 2 is further provided outside the loop-shaped first antenna element 4 at a portion below the first opening 12 and surrounded by the first antenna element 4 and the second antenna element 8. A third opening 16 is provided to penetrate.

Each of the first opening 12, the second opening 14, and the third opening 16 has a rectangular shape, and has a left peripheral portion V 12 of the first opening 12 and a left edge of the third opening 16. Each of the peripheral portions V16 is configured to have a linear portion, and each of the linear portions is configured to be linear in the base film 2. Also, the right peripheral portion V14 of the second opening 14 has a straight line portion that is parallel to a straight line portion of the left peripheral portion V12 of the first opening portion 12 and the left peripheral portion V16 of the third opening portion 16. Be composed.

In the base film portion of the hatched region 17 in FIG. 1 sandwiched between the second opening 14 and the third opening 16, either the first antenna element 4 or the second antenna element 8 is provided. Are not formed.

Further, the distance Ld at the closest portion between the peripheral edge of the first opening 12 and the peripheral edge of the second opening 14 is determined by the distance between the peripheral edge of the first opening 12 and the peripheral edge of the third opening 16. The distance Ld is set to be larger than the distance Le at the closest part of the above, and the Ld is set so as to satisfy 5 mm ≦ Ld ≦ 120 mm.

Similarly, the distance Lf at the closest point between the peripheral edge of the third opening 16 and the peripheral edge of the second opening 14 is determined by the distance between the peripheral edge of the first opening 12 and the peripheral edge of the third opening 16. The distance Lf is set to be larger than the distance Le at the closest part of the part, and the Lf is set to satisfy 5 mm ≦ Lf ≦ 120 mm.

The distance Ld at the closest point between the peripheral edge of the first opening 12 and the peripheral edge of the second opening 14, and the distance Ld between the peripheral edge of the third opening 16 and the peripheral edge of the second opening 14. The upper limit of 120 mm of the distance Lf at the closest approach portion allows each finger of one hand to be inserted into the first opening and the second opening, or the third opening and the second opening. On the other hand, the lower limit of 5 mm for Ld and Lf is such that when each finger of one hand is inserted into each opening of the film antenna and held with one hand, the film antenna moves up and down. It is set to have an appropriate strength so that it does not bend in any direction. By setting the Ld or the Lf to a predetermined value within the above range, the film antenna can be stuck with one hand without touching the adhesive-coated surface, and the sticking operation is simplified. it can. In the embodiment shown in FIG. 1, Ld = 30 mm, Lf = 30 mm, and Le = 5 mm.

Next, a method of attaching the attachment type film antenna will be described. <Attaching Method> As shown in FIG. 3, the adhesive film 51 of the present invention has an adhesive layer 51 formed on the base film 2 when it is commercially available. The base film 2 and the antenna elements 4 and 8 are fixed. Further, a protective film 52 is formed on the antenna elements 4 and 8 to prevent the antenna elements 4 and 8 from being oxidized and protected from damage. Further, an adhesive layer 56 is formed on the protective film 52, and a protective film 58 is provided on the adhesive layer 56. When the worker pulls the protection film 58, the protection film 58 and the pressure-sensitive adhesive layer 56 are separated, and the pressure-sensitive adhesive layer 56 is exposed. The operator attaches the antenna with the exposed adhesive layer 56 to a desired glass-like position. In this case, it is preferable to adhere to the inside of the window in consideration of weather resistance.

According to experimental data, the inventors have found that when installing a plurality of receiving antennas having different reception frequencies in a vehicle, the antennas receiving relatively low frequencies are located on the vehicle center side. We found that the reception performance at all reception frequencies improved.

Thus, when the sticking type film antenna 10 according to the present invention is stuck on a vehicle, as shown in FIG. 1, the first antenna for receiving a relatively high frequency is located at a position far from the center of the vehicle, that is, outside the vehicle. The antenna element 4 is arranged, and the second antenna element 8 for relatively low frequency reception is attached to a position close to the center of the vehicle so as to be arranged.

[0044]

【Example】

 Next, an embodiment of the pasting type film antenna according to the present invention will be described in comparison with a conventional antenna in terms of reception performance. <Receiving Performance> FIGS. 7 to 10 show the receiving characteristics when two sticking film antennas 10 according to the present invention shown in FIG. 1 are stuck to the windshield of a vehicle as shown in FIG. The antenna 22 and the antenna 24 are arranged on one film, and the antenna 26 and the antenna 28 are arranged on another film. Of these, the antenna 28 is an antenna dedicated to receiving VICS radio waves. It is.

Each of the reception characteristics shown in FIGS. 7 to 9 is obtained by performing a diversity process on the reception signals of the antennas 22, 24, and 26. FIGS. 7, 8, and 9 show the reception characteristics of 88 MHz to 108 MHz, respectively. (FM radio wave or TV broadcast wave low VHF band of 1CH to 3CH), 170MHz to 225MHz (TV broadcast wave of 4CH to 12CH high VHF band), 470MHz to 770MHz (UHF band) reception It is a measurement result of the gain G. (Note that the reception gain G is a gain difference when the reception gain of a standard dipole antenna is 0 dB, and the same applies to the following description.) The reception characteristics shown in FIG. This is a measurement result of the reception gain G in a band of 76 MHz to 90 MHz (VICS band).

For comparison of reception performance, FIG. 11 shows the reception characteristics when the pasting-type film antennas 32, 34, and 36 according to the first conventional example are attached to the windshield of a vehicle as shown in FIG. 13 to FIG. Each of the antennas 32, 34, and 36 is a loop-shaped antenna, each of which is disposed on one film, and the dimensions of each part are as shown in FIG.

The reception characteristics shown in FIGS. 11 to 13 are obtained by performing diversity processing on the reception signals of the antennas 32, 34, and 36. FIGS. 11, 12, and 13 respectively show the reception characteristics. 7, similarly to FIGS. 8 and 9, 88 MHz to 108 MHz (low VHF band of 1 to 3 CH of FM radio wave or TV broadcast wave), 170 MHz to 225 MHz (high VHF band of 4 to 12 CH of TV broadcast wave) And 470 MHz to 770 MHz (UHF band).

Further, as shown in FIG. 6, for comparison of the reception performance, the reception characteristics when the pasting-type film antennas 42, 44, 46 according to the second conventional example are stuck on the windshield of the vehicle are shown. This is shown in FIGS. Each of the antennas 42, 44, and 46 is a loop antenna. The antenna 42 and the antenna 44 are disposed on one film, and the antenna 46 is disposed on another film. The dimensions are as shown in FIG.

Each of the reception characteristics shown in FIGS. 14 to 16 is obtained by performing a diversity process on the reception signals of the antennas 42, 44, and 46. FIGS. 14, 15, and 16 show the reception characteristics, respectively. 7, similarly to FIGS. 8 and 9, 88 MHz to 108 MHz (low VHF band of 1 to 3 CH of FM radio wave or TV broadcast wave), 170 MHz to 225 MHz (high VHF band of 4 to 12 CH of TV broadcast wave) 7 shows the measurement results of the reception gain G2 in the band of 470 MHz to 770 MHz (UHF band).

Table 1 below compares the reception characteristics in the low VHF band of each of the pasted film antennas shown in FIGS. 7, 11, and 14. For comparison of the reception performance, the gain difference G-G1 between the reception gain G of the adhesive film antenna according to the present invention shown in FIG. 7 and the reception gain G1 of the adhesive film antenna according to the first conventional example shown in FIG. (DB) in the middle, the gain difference G between the reception gain G of the adhesive film antenna according to the present invention shown in FIG. 7 and the reception gain G2 of the adhesive film antenna according to the second conventional example shown in FIG. -G2 (dB) is shown below.

[0051]

[Table 1] In the low VHF band, as shown in Table 1, the reception gain G of the adhesive film antenna according to the present invention is 0.0 dB lower than the reception gain G1 of the adhesive film antenna of the first conventional example at 88 MHz to 102 MHz. It can be seen that the gain is improved up to 3.8 dB, and the gain is reduced at 103 MHz to 108 MHz, but the decrease is very small, 0.3 dB to 2.0 dB, which is a problem in actual use. There is no. In addition, the reception gain G of the pasted film antenna according to the present invention is improved by 0.2 dB to 1.7 dB at all frequencies over the reception gain G2 of the pasted film antenna according to the second conventional example. It can be seen that it can be obtained. Furthermore, the average value of the reception gain G within the evaluation frequency range of the low VHF band is improved by 0.8476 dB from the average value of the reception gain G1, and is 0.9857 dB higher than the average value of the reception gain G2. It can be seen that it is improved.

Similarly, Table 2 below shows a comparison of the reception characteristics in the high VHF band of each of the pasted film antennas shown in FIGS. 8, 12, and 15 above. For comparison of the reception performance, the gain difference G- between the reception gain G of the adhesive film antenna of the present invention shown in FIG. 8 and the reception gain G1 of the adhesive film antenna of the first conventional example shown in FIG. With G1 (dB) in the middle, the gain difference between the reception gain G by the adhesive film antenna according to the present invention shown in FIG. 8 and the reception gain G2 by the adhesive film antenna according to the second conventional example shown in FIG. G-G2 (dB) is shown at the bottom.

[0053]

[Table 2] In the high VHF band, according to Table 2 above, the reception gain G of the adhesive film antenna according to the present invention is lower than the reception gain G1 of the adhesive film antenna of the first conventional example in 217.5 MHz to 225 MHz. It can be seen that the gain is improved from 0.3 dB to 1.4 dB, and the gain is reduced from 170 MHz to 214 MHz. However, the amount of reduction is very small, from 0.6 dB to 2.0 dB, which poses a problem in actual use. There is no. Also, the reception gain G of the pasting-type film antenna according to the present invention is 177.5 MHz, 190 MHz to 192.5 MHz, 205 MHz to 212.5 MHz higher than the receiving gain G2 of the pasting-type film antenna according to the second conventional example. It can be seen that the gain is improved from 0.0 dB to 2.3 dB at all frequencies except for the above. Also, it can be seen that the gain decreases at the above-mentioned 177.5 MHz, 190 MHz to 192.5 MHz, and 205 MHz to 212.5 MHz, but the amount of decrease is very small, 0.1 dB to 0.7 dB. No problem. Further, it can be seen that the average value of the reception gain G within the evaluation frequency range of the high VHF band is improved by 0.5348 dB from the average value of the reception gain G2, and is higher than the average value of the reception gain G1. , 0.8565 dB, but the amount of decrease is negligible and does not pose a problem in actual use.

Further, similarly to the above, Table 3 below compares the reception characteristics in the UHF band of each of the pasted film antennas shown in FIG. 9, FIG. 13 and FIG. For comparison of the reception performance, the gain difference G- between the reception gain G of the adhesive film antenna of the present invention shown in FIG. 9 and the reception gain G1 of the adhesive film antenna of the first conventional example shown in FIG. With G1 (dB) in the middle, the gain difference between the reception gain G by the adhesive film antenna according to the present invention shown in FIG. 9 and the reception gain G2 by the adhesive film antenna according to the second conventional example shown in FIG. G-G2 (dB) is shown at the bottom.

[0055]

[Table 3] In the UHF band, according to Table 3 above, the reception gain G of the adhesive film antenna according to the present invention is 530 MHz to 557 MHz, 690 MHz to 710 MHz, more than the reception gain G1 of the adhesive film antenna according to the first conventional example. At 770 MHz, the gain is increased by 0.1 dB to 2.7 dB, and the gain is decreased at 470 MHz to 510 MHz, 570 MHz to 670 MHz, and 750 MHz. 0.3 dB to 2.2 dB, which is negligible and does not pose a problem in actual use. In addition, the reception gain G of the pasted film antenna according to the present invention is improved by 0.4 dB to 5.4 dB at all frequencies compared to the reception gain G2 of the pasted film antenna according to the second conventional example. It can be seen that it can be obtained. Also, it can be seen that the average value of the reception gain G within the evaluation frequency range of the UHF band is improved by 2.6563 dB from the average value of the reception gain G2, and the average value of 0. Although it can be seen that the gain is reduced by 8688 dB, the amount of decrease is very small and does not cause any problem in actual use.

As described above, the first antenna element 4 which is a rectangular loop-shaped antenna suitable for receiving a wide first frequency band at a relatively high frequency and a narrow second frequency band at a relatively low frequency are received. The above-mentioned second antenna element 8 which is a pole-shaped antenna suitable for mounting is provided on one base film 2, and the length and layout of each antenna element are set as described above. The elements can reduce the size of the adhesive film antenna 10 without deteriorating performance due to mutual interference, facilitate the assembly work, and reduce the cost per antenna element.

The maximum width Lmax of the base film 2 is set to a rectangular outer shape of 335 mm or less, and the first antenna element 4 and the second antenna element 8 provided on the base film 2 are arranged in the vertical direction. The maximum separation distance L22 is set to 100 mm or less, or the first antenna element 4 and the second antenna element 8 are arranged so as to be shielded from the passenger compartment by lowering the sun visor. In addition, the first power supply point 6 and the second power supply point 9 are also disposed so as to be shielded when the sun visor is lowered, as viewed from the vehicle interior, so that the driver's view can be secured. It is possible to improve the appearance when looking outside the vehicle.

By providing the first opening 12, the second opening 14, and the third opening 16 in the base film 2, it is possible to reduce costs by reducing weight and materials.

The left peripheral edge V12 of the first opening 12 and the left peripheral edge V16 of the third opening 16 have straight portions, and the right side of the second opening 14 is parallel to these straight portions. Since the peripheral portion V14 also has a straight portion, it is possible to easily insert each finger of one hand into each opening, and the above-mentioned adhesive film antenna has a suitable strength in the vertical direction. When the film antenna is held with one hand, the pasted film antenna does not bend in the vertical direction, and the sticking film antenna is held with one hand without touching the adhesive-coated surface. Therefore, the assembling work can be facilitated.

Further, by providing the hatched area 17 in FIG. 1 sandwiched between the second opening 14 and the third opening 16, in which neither the first antenna element 4 nor the second antenna element 8 is formed, The adhesive film antenna has an appropriate strength in the vertical direction, and when the film antenna is held with one hand, the adhesive film antenna does not bend in the vertical direction. Since the sticking work can be performed by holding the sticking type film antenna with one hand without touching, the assembling work can be further facilitated.

The distance Ld between the peripheral edge of the first opening 12 and the peripheral edge of the second opening 14, and the distance Ld between the peripheral edge of the first opening 12 and the peripheral edge of the third opening 16. The distance Le at the approaching portion is set so as to satisfy Le <Ld and 5 mm ≦ Ld ≦ 120 mm. Similarly, the closest distance between the peripheral edge of the third opening 16 and the peripheral edge of the second opening 14 is set. The distance Lf at the portion and the distance Le at the nearest portion between the peripheral edge of the first opening 12 and the peripheral edge of the third opening 16 are set to satisfy Le <Lf and 5 mm ≦ Lf ≦ 120 mm. As a result, the film antenna has an appropriate strength in the vertical direction, and furthermore, does not bend in the vertical direction. Piece without touching the adhesive coated surface Sticking work by hand can be performed, and assembling work can be further facilitated.

Further, the receiving performance of the adhesive film antenna according to the present invention is 103 MHz to 108 MHz, 170 MHz to 214 MHz, 470 MHz to 510 MHz, and 570 MHz, compared with the receiving performance of the adhesive film antenna according to the first conventional example. At all frequencies except z to 670 MHz and 750 MHz, the gain is improved from 0.0 dB to 3.8 dB, and it can be seen that the gain is improved. Also, at each of the above frequencies, except for the local 470 MHz, the gain reduction amount of the reception performance is 0.3 dB to 2. It is very small, 2 dB, and does not pose a problem in actual use.

Further, the average value of the reception gain G within the evaluation frequency range in the low VHF band is equal to 0. The gain has been improved by 8476 dB, and the average value of the reception gain G within the evaluation frequency range in the high VHF band and UHF band is 0.8565 dB and 0.8688 dB. The amount is negligible and does not pose a problem in actual use. The receiving performance of the pasted film antenna according to the present invention is equivalent to the receiving performance of the pasted film antenna according to the first conventional example. I understand.

Thus, the adhesive film antenna 10 according to the present invention is smaller than the adhesive film antenna according to the first conventional example in which one antenna element is arranged on one base film, and one antenna element is provided. In addition to lowering the cost per unit, facilitating the assembling work, and improving the appearance, it is possible to obtain the same level of receiving performance as a whole.

Further, the receiving performance of the pasted film antenna according to the present invention is 177.5 MHz, 190 MHz to 192.5 MHz, 205 MHz to 212 compared with the receiving performance of the pasted film antenna according to the second conventional example. It can be seen that the gain is improved from 0.0 dB to 5.4 dB at all frequencies except for 0.5 MHz, which is improved. Also, at each of the above frequencies, the gain reduction amount of the reception performance is 0.1 dB to 0.1 dB. 7 dB, which is negligible in practical use.

The average value of the reception gain G within the evaluation frequency range in the low VHF band, the high VHF band, and the UHF band is 0.9857 dB, 0.5348 dB, and 2.6563 dB. Is also improved as a whole, and it can be seen that the receiving performance of the pasted film antenna according to the present invention is superior to the receiving performance of the pasted film antenna according to the second conventional example.

As described above, with the adhesive film antenna 10 according to the present invention, a plurality of antennas 42 and 44 are arranged on one base film in the same manner as the adhesive film antenna according to the present invention. It is possible to improve the receiving performance as compared with the pasting type film antenna according to the second conventional example which has the same cost per book, assembling workability, and appearance.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a sticking type film antenna according to the present invention.

FIG. 2 is a diagram illustrating a state in which the adhesive film antenna according to the present invention is mounted on a vehicle windshield.

FIG. 3 is a cross-sectional view illustrating the structure of the adhesive film antenna according to the present invention.

FIG. 4 is a diagram showing the configuration of the vehicle windshield when measuring the reception performance of the pasted film antenna according to the present invention.

FIG. 5 is a diagram showing the shape of each antenna and the configuration of a vehicle windshield when measuring the receiving performance of the pasted film antenna according to the first conventional example.

FIG. 6 is a diagram showing the shape of each antenna and the configuration of a vehicle windshield when measuring the reception performance of a pasted film antenna according to a second conventional example.

FIG. 7 shows the reception characteristics (88 MHz to 108 MHz) of FIG.
FIG.

FIG. 8 shows the reception characteristics (170 MHz to 225 MH) of FIG.
FIG.

FIG. 9 shows the reception characteristics (470 MHz to 770 MH) of FIG.
FIG.

FIG. 10 shows the reception characteristics (76 MHz to 90 MHz) of FIG.
FIG.

FIG. 11 shows the reception characteristics (88 MHz to 108 MH) of FIG.
FIG.

FIG. 12 shows the reception characteristics (170 MHz to 225 M) of FIG.
(Hz band).

FIG. 13 shows the reception characteristics (470 MHz to 770 M) of FIG.
(Hz band).

FIG. 14 shows the reception characteristics (88 MHz to 108 MH) of FIG.
FIG.

FIG. 15 shows the reception characteristics (170 MHz to 225 M) of FIG.
(Hz band).

FIG. 16 shows the reception characteristics (470 MHz to 770 M) of FIG.
(Hz band).

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 2 ... Base film 4 ... 1st antenna element 6 ... 1st feeding point 8 ... 2nd antenna element 9 ... 2nd feeding point 10 ... Adhesive type film antenna of this invention 12 ... 1st opening 14 ... 2nd opening 16 … The third opening

Claims (8)

[Utility model registration claims] An adhesive film antenna for attaching an antenna element to a non-conductive material and receiving a radio wave of a desired wavelength, wherein the adhesive film antenna is formed at a corner of a base film, forms a loop shape, and is formed at a first feeding point. A first antenna element to be connected, formed on the base film, forming a pole shape,
After temporarily extending from a second feeding point provided adjacent to the first feeding point to a side opposite to the first antenna element,
The base film is bent in a U-shape, the end of which is a second antenna element disposed close to the first antenna element, and the base film is surrounded by the base film portion surrounded by the loop-shaped first antenna element. The base film penetrates a first opening provided to penetrate, and the base film portion surrounded by the first antenna element and the second antenna element outside the loop-shaped first antenna element. And a second opening provided as described above. 2. The sticking type film antenna according to claim 1, wherein the first opening and the second opening are arranged side by side in a horizontal direction, and the second antenna element is arranged near a terminal end thereof. The first antenna element is arranged along the first antenna element, and the first antenna element is arranged outside the loop-shaped first antenna element.
Affixing, characterized by having a third opening surrounded by the antenna element and the second antenna element and provided in the base film portion below the first opening so as to penetrate the base film. Type film antenna. 3. The adhesive film antenna according to claim 2, wherein a peripheral edge of the first opening and a peripheral edge of the third opening are:
Each of the portions closest to the second opening has a straight portion, and the straight portions are arranged so as to be linear in the base film, and the peripheral portion of the second opening is A portion closest to the first opening, having a linear portion parallel to each of the linear portions of the peripheral portion of the first opening portion and the peripheral portion of the third opening portion; antenna. 4. The adhesive film antenna according to claim 2, wherein the first antenna element is provided in a base film portion sandwiched between the second opening and the third opening. And a structure in which none of the second antenna element is formed. 5. The adhesive film antenna according to claim 2, wherein a distance Ld between a peripheral portion of the first opening and a peripheral portion of the second opening is the closest. Distance Le at the closest portion between the peripheral portion of the first opening and the peripheral portion of the third opening.
Is configured to satisfy Le <Ld. 6. The adhesive film antenna according to claim 3, wherein a distance Lf between a peripheral edge of the third opening and a peripheral edge of the second opening is closest to the first opening. Ld at the closest point between the peripheral edge of the second opening and the peripheral edge of the second opening
And the distance Le at the closest portion between the peripheral portion of the first opening and the peripheral portion of the third opening is Le <Lf and Le.
<Attachment type film antenna characterized by being comprised so that <Ld. 7. A sticking type film antenna according to claim 5, wherein said Ld is set to satisfy 5 mm ≦ Ld ≦ 120 mm. 8. The sticking type film antenna according to claim 6, wherein said Lf is such that 5 mm ≦ Lf ≦ 120 mm.