JP2008104242A - On-vehicle antenna and diversity receiver - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily perform operation accompanying installation of antenna to vehicles, and to eliminate degradation in receiving quality by a well-suited grounding connection. <P>SOLUTION: A film antenna 2, 3 pasted up on the front glass 4 of a vehicle has a plurality of antenna elements 11, 12, 21, 22 formed on film substrates 10, 20. Amplifiers 16, 26 are arranged on pillars 6, 7 and grounding is given to a high-frequency component by high-frequency grounding members 17, 27 in a portion close to feeding points 15, 25 to the antenna elements 11, 12, 21, 22. The high-frequency grounding members 17, 27 can be mounted only by pasting up on a coated film and the like covering the exterior parts of a vehicle body, and no peeling operation and the like are required to coated films. Accordingly, easy operation can be expected accompanying the antenna installation to the vehicle. The grounding to a DC component is implemented through a DC earth 35 close to a selector 8 or a receiver 9 apart from the feeding points 15, 25. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a vehicle-mounted antenna mounted on a vehicle body exterior part of a vehicle, and a diversity receiver using such a vehicle-mounted antenna.

  Conventionally, various in-vehicle antennas have been used so that broadcast radio waves and communication radio waves can be received even when a vehicle such as an automobile is moving. A film antenna is known as an antenna attached to a window glass or the like of a vehicle (see, for example, Patent Document 1). In this film antenna, a plurality of pairs of antenna elements are formed on a film substrate, and an amplifier having a connector is connected to one end of the film substrate. It is described that the film substrate and the amplifier are attached to the rear glass or the like of the vehicle, and an earth wire is formed by an element on the film substrate, so that it is not necessary to connect the earth to the ground on the amplifier side. It is also disclosed that a plurality of sets of film antennas and amplifiers are provided and switched for diversity reception. Note that the antenna can be switched electrically (see, for example, Patent Document 2).

  A configuration in which an antenna pattern is directly formed on a window glass of an automobile and a booster amplifier is provided on the glass surface is also known (see, for example, Patent Document 3). In addition, a vehicle-mounted plane that receives a weak signal transmitted from a GPS satellite by sequentially forming a conductor layer for a radiating element, a dielectric layer, and a ground conductor layer from the bottom on at least a part of the window glass plate of the vehicle. An antenna configuration is also known (see, for example, Patent Document 4). Furthermore, a configuration is known in which a hole is formed in a ceiling plate of a vehicle body and an antenna and an amplifier that receive weak radio waves from a GPS satellite are mounted (see, for example, Patent Document 5).

Japanese Patent No. 3294737 Japanese translation of PCT publication No. 2002-510925 Japanese Patent No. 3175777 Japanese Patent Laid-Open No. 5-63423 JP-A-5-63419

  A film antenna that is attached to a window glass and used as a radio wave receiving antenna to be mounted on a vehicle is suitable. However, as described in the column of the problem to be solved by the invention of Patent Document 1, it is necessary to connect the ground to the vehicle body, but it is difficult for a general user. Patent Document 1 describes that a ground wire can be formed on a film substrate and can be connected to an amplifier with a connector, so that problems associated with ground connection can be solved. However, there is no description about the reason why the connection to the ground is possible only by connecting to the ground wire formed together with the element on the film substrate to be pasted on the glass surface via the connector.

  When the amplifier is installed in the vicinity of the antenna, the ground connection of the amplifier needs to be DC grounded including a direct current component with respect to the vehicle body. Although the car body itself is a conductor such as metal, it is usually painted with a paint which is an electrical insulator. In order to perform DC grounding on such a vehicle body, it is necessary to make a hole in the vehicle body and connect the grounding with a bolt or the like as processing for the vehicle body.

  In consideration of workability, it is also possible not to install the amplifier near the antenna. However, in this case, the feeding coaxial cable from the antenna to the amplifier becomes long, and the S / N ratio as the signal-to-noise ratio of the high-frequency reception signal occurs due to the cable loss, and the reception quality deteriorates. In addition, when the length of the coaxial cable is increased, especially when the impedance of the coaxial cable does not match the impedance at the feeding point of the antenna, noise generated from the vehicle is induced in the feeding coaxial cable, Noise is induced in the coaxial cable for power supply, resulting in deterioration of reception quality.

  An object of the present invention relates to a vehicle-mounted antenna and a diversity receiver that can easily perform work associated with installation of an antenna in a vehicle and perform appropriate ground connection to prevent a reduction in reception quality.

The present invention includes an antenna element attached to a dielectric portion of an exterior portion of a vehicle body,
A high-frequency grounding member that is provided in the vicinity of the feeding point of the antenna element, is mounted on a conductor portion of the vehicle body, is capacitively coupled, and performs electrical grounding related to a high-frequency component;
The vehicle-mounted antenna includes an amplifier that is provided in the vicinity of the feeding point and amplifies a high-frequency reception signal input from the feeding point.

  According to the present invention, the vehicle-mounted antenna includes an antenna element, a high-frequency grounding member, and an amplifier. Since the antenna element is attached to the dielectric part of the exterior part of the car body, it is attached to an electrically insulating part such as a window glass to avoid the electrical influence of a metal car body and so on. Can be received. The high frequency grounding member is provided in the vicinity of the feeding point of the antenna element, and is mounted on the conductor portion of the vehicle body and capacitively coupled to electrically ground the high frequency component. On the other hand, it is possible to enhance the reception performance of the antenna by electrically grounding the high frequency component. Since electrical grounding is performed by capacitive coupling, there is no need to make direct electrical contact, and even if the conductor part of the vehicle body is sufficiently painted with paint, there is no need for a process of peeling the coating, and it is easy It is possible to easily perform work associated with installation of an antenna on a vehicle that can be grounded, and perform appropriate ground connection to prevent a reduction in reception quality. The amplifier is provided near the feeding point and amplifies the high-frequency reception signal input from the feeding point, so even a weak high-frequency reception signal received by the antenna element is not easily affected by noise generated in the vehicle. It is possible to amplify the signal and prevent the reception quality from being lowered.

  In the present invention, the amplifier is directly connected to the feeding point and the high-frequency grounding member.

  According to the present invention, it is possible to improve the reception quality by installing the amplifier close to the feeding point to the antenna element and the high-frequency grounding member, making it difficult for noise and the like to enter the input side of the amplifier.

  In the present invention, the amplifier is connected to the feeding point and the high-frequency grounding member via a coaxial cable.

  According to the present invention, the feeding point to the antenna element and the high-frequency grounding member are connected to the input side of the amplifier via the coaxial cable, so that the installation position of the amplifier can be easily selected.

In the present invention, the amplifier outputs the amplified high frequency received signal via a coaxial cable,
The grounding of the direct current component of the amplifier is performed on the vehicle body in the vicinity where the coaxial cable is connected to a vehicle-mounted device that processes a high-frequency received signal.

  According to the present invention, the electrical grounding to the vehicle body related to the DC component of the amplifier is performed in the vicinity where the vehicle-mounted device that processes the high-frequency received signal amplified by the amplifier is mounted on the vehicle. Such an in-vehicle device is installed in a vehicle interior or the like, and can be easily electrically grounded to the vehicle body.

In the present invention, the surface of the conductor portion of the vehicle body is covered with an electrically insulating coating,
The high-frequency grounding member is a metal thin plate member affixed on the electrically insulating film.

  According to the present invention, an electrical insulating property is usually obtained by applying a high-frequency grounding member to an exterior portion of a vehicle body in which a conductor such as a steel material is covered with an electrical insulating coating such as a coating. Capacitive coupling is generated between the conductor and the conductor through the film, and electrical grounding can be performed for the high frequency component. The electrically insulating coating does not need to be peeled off, does not require a lot of work, and does not impair the corrosion resistance and aesthetic appearance, and can be grounded.

In the present invention, a plurality of antenna elements are connected to the amplifier.
The high-frequency grounding member is configured to perform common grounding of high-frequency components for the plurality of antenna elements.

  According to the present invention, the grounding for the high-frequency component based on the capacitive coupling to the conductor portion of the vehicle body by the high-frequency grounding member can be performed in common for the plurality of antenna elements, so the number of places where the high-frequency grounding member is mounted The work required for mounting can be easily performed.

  In the present invention, the amplifier includes a switch for selecting an antenna element for amplifying a high frequency received signal from the plurality of antenna elements.

  According to the present invention, a plurality of antenna elements can be connected to an amplifier, and an antenna element that amplifies a high-frequency reception signal can be selected by a switch, so that reception of different frequency bands by changing the shape of the antenna element, Diversity reception and the like can be easily performed by changing the arrangement of the antenna elements, and even if there is one signal line for deriving the output of the amplifier, received signals from a plurality of antenna elements can be selected and transferred.

Furthermore, the present invention is a plurality of antenna elements that are attached to a dielectric portion of the exterior portion of the vehicle body and are provided close to a feeding point;
A high-frequency grounding member provided in the vicinity of a feeding point of the plurality of antenna elements, mounted on a conductor portion of a vehicle body, capacitively coupled, and electrically grounding a high-frequency component in common;
An amplifier that is provided in the vicinity of the feeding point and amplifies a high-frequency reception signal input from the feeding point;
A switch provided in the amplifier for selecting an antenna element for amplifying a high-frequency received signal;
Diversity comprising: selective reception means for processing a high-frequency received signal amplified by the amplifier and remotely controlling the switch to select an antenna element having good reception quality regarding the high-frequency received signal It is a receiving device.

  According to the present invention, the diversity receiver includes a plurality of antenna elements, a high-frequency grounding member, an amplifier, a switch, and selective reception means. The plurality of antenna elements are mounted on a dielectric part of the exterior portion of the vehicle body, for example, on a window glass, and are provided close to a feeding point for connection to a feeding line such as a coaxial cable. The high-frequency grounding member is provided in the vicinity of the feeding points of the plurality of antenna elements, and is attached to the conductor portion of the vehicle body for capacitive coupling. Even without exposing the conductor portion of the vehicle body, electrical grounding relating to the high-frequency component can be easily performed. Since the amplifier is provided in the vicinity of the power supply point and a high-frequency reception signal input from the power supply point is amplified, mixing of noise and the like is reduced, and reception quality can be improved. Since the switch is provided in the amplifier and selects an antenna element that amplifies the high-frequency reception signal, the high-frequency signal can be amplified with one amplifier for the plurality of antenna elements. The selective receiving means processes the high-frequency received signal amplified by the amplifier, and remotely controls the switch to select an antenna element with good reception quality related to the high-frequency received signal. Even if the environment changes, it is possible to continue reception by selecting an antenna element with good reception quality.

Further, in the present invention, the combination of the plurality of antenna elements and the amplifier is provided in different places of the exterior part of the vehicle body,
The selection receiving unit performs selection of the plurality of amplifiers and selection of an antenna element connected to the amplifiers.

  According to the present invention, a combination of a plurality of antenna elements and an amplifier is arranged at a different location on the exterior part of the vehicle body, a location of the antenna is selected by selecting the amplifier, and a plurality of locations provided at the selected location An antenna element can be selected to obtain good reception quality.

  As described above, according to the present invention, the antenna element is mounted on the dielectric portion of the exterior portion of the vehicle body, and the high frequency component for the conductor portion of the vehicle body from the vicinity of the feeding point of the antenna element via the high frequency grounding member. Electrical grounding can be performed. Since electrical grounding is performed by capacitive coupling, it is not necessary to make direct contact, and even if the conductor part of the vehicle body is sufficiently painted with paint, it can be electrically grounded, so the antenna is installed on the vehicle Therefore, it is possible to easily perform the work associated with the above and to make a proper ground connection to prevent the reception quality from being deteriorated. The amplifier is provided in the vicinity of the feeding point, and even a weak high-frequency reception signal received by the antenna element can be amplified at a position where it is difficult to be affected by noise generated in the vehicle, thereby preventing a reduction in reception quality.

  In addition, according to the present invention, the amplifier can be installed close to the feeding point to the antenna element and the high-frequency grounding member, and noise can be prevented from being mixed, thereby improving the reception quality.

  Further, according to the present invention, since the feeding point to the antenna element and the high-frequency grounding member are connected to the input side of the amplifier via a coaxial cable, the distance between the amplifier and the feeding point can be increased to some extent. The position can be easily selected.

  Further, according to the present invention, the electrical grounding to the vehicle body related to the DC component of the amplifier is performed in the vicinity of the mounting position of the in-vehicle device that processes the high-frequency received signal amplified by the amplifier. In-vehicle devices are often installed inside the vehicle body, and can easily be electrically grounded to the vehicle body.

  Further, according to the present invention, the high frequency grounding member is attached to the exterior portion of the vehicle body in which the conductor is covered with an electrically insulating film such as a coating film, thereby electrically Therefore, it is not necessary to peel off the electrically insulating coating, so that the work is not time-consuming, and the grounding can be performed without damaging the corrosion resistance and the appearance.

  Further, according to the present invention, since a plurality of antenna elements can be commonly grounded with respect to the high-frequency component to the conductor portion of the vehicle body, the number of places where the high-frequency grounding member is attached is reduced, and the work required for mounting is facilitated. Can be done.

  In addition, according to the present invention, reception of different frequency bands by changing the shape of the antenna element, diversity reception by changing the arrangement of the antenna elements, and the like can be easily performed, and even one signal line for deriving the output of the amplifier can be obtained. It is possible to select and transfer received signals from a plurality of antenna elements.

  Further, according to the present invention, the switch provided in the high-frequency grounding member amplifier near the feeding point of the plurality of antenna elements is mounted on the dielectric portion of the exterior portion of the vehicle body. Since the antenna element for amplifying the signal is selected, a high-frequency signal can be amplified with a single amplifier for a plurality of antenna elements. The switch is controlled remotely by the selective receiving means, and selects an antenna element having a good reception quality with respect to the high-frequency reception signal. Therefore, even if the reception environment changes as the vehicle moves, the reception can be performed with a good reception quality. You can continue.

  Further, according to the present invention, since a plurality of combinations of a plurality of antenna elements and amplifiers are used and arranged at different locations on the exterior of the vehicle body, the amplifier is selected, the antenna location is selected, and the selected amplifier is further selected. A plurality of antenna elements connected to can be selected so that good reception quality can be obtained.

  FIG. 1 shows a schematic electrical configuration of a vehicle-mounted antenna 1 according to an embodiment of the present invention. In this embodiment, the two film antennas 2 and 3 are affixed on the inner surface of the windshield 4 of the vehicle of the automobile. The film antennas 2 and 3 are attached to the upper portion of the windshield 4 between the rearview mirror 5 and the pillar portions 6 and 7 on both sides. The antenna element that is actually used for reception is selected by the selector 8. Selection by the selector 8 is switched by control by the receiver 9.

  In one film antenna 2, a plurality of, for example, two antenna elements 11, 12 are formed on the surface of a synthetic resin film substrate 10. It is also possible to form three or more antenna elements. Each antenna element 11, 12 is drawn from the windshield 4 to the pillar portion 6 side through the feeder lines 13, 14, and is connected to the input terminal of the amplifier 16 at a feeding point 15 provided in the pillar portion 6. The input side of the amplifier 16 is also grounded for a high frequency component via the high frequency grounding member 17. The high-frequency grounding member 17 has a metal foil 18, and the other end of a connection line 19 connected at one end to the metal foil 18 is connected to the input side of the amplifier 16 at the feeding point 15 described above. The metal foil 18 is electrically connected to the pillar portion 6 by capacitive coupling.

  Even in the other film antenna 3, a plurality of two antenna elements 21 and 22 are formed on the surface of the synthetic resin film substrate 20. Each antenna element 21, 22 is drawn from the windshield 4 to the pillar portion 7 side via the feeder lines 23, 24, and is connected to the input terminal of the amplifier 26 at a feeding point 25 provided on the pillar portion 7. The input side of the amplifier 26 is also grounded with respect to the high frequency component via the high frequency grounding member 27. The high-frequency grounding member 27 has a metal foil 28, and the other end of the connection line 29 connected at one end to the metal foil 28 is connected to the input side of the amplifier 26 at the feeding point 25 described above. The metal foil 28 is electrically connected to the pillar portion 7 by capacitive coupling.

  The feeding points 15 and 25 of the two film antennas 2 and 3 are provided on the upper portions of the pillar portions 6 and 7, respectively. Amplifiers 16 and 26 are installed at the feeding points 15 and 25, respectively. The amplifiers 16 and 26 and the high-frequency grounding members 17 and 27 are installed on the back side of the interior material covering the surfaces of the pillar portions 6 and 7 so that they cannot be seen from the passenger compartment. The amplifiers 16 and 26 have two amplifier circuits connected to the feeder lines 13 and 14 and 23 and 24 from the antenna elements 11 and 12 and 21 and 22, respectively, and commonly connected to the high-frequency connection members 17 and 27, respectively. included. The output from each amplifier circuit is input to the selector 8 via coaxial cables 31, 32, 33 and 34. In the selector 8, the outer conductors of the coaxial cables 31, 32, 33, 34 are directly connected to the vehicle body as a DC ground 35. In the selector 8, one of the coaxial cables 31, 32, 33, 34 is selected and connected to the coaxial cable 36. The coaxial cable 36 is connected to the receiver 9 together with control lines 37 and 38 that control selection by the selector 8. The selector 8 and the receiver 9 are installed on the floor or trunk room of the passenger compartment, and the DC ground 35 can be easily connected using bolts for fixing various devices. The selector 8 may be built in the receiver 9.

  FIG. 2 shows an electrical circuit configuration corresponding to the embodiment of FIG. For convenience of explanation, the configuration on the one amplifier 16 side is mainly shown, but the other amplifier 26 side is also equivalent. In the amplifier 16, an amplifier circuit 41 whose input side is connected to the antenna element 11 via the feeder line 13 is provided. The amplifier circuit 41 has capacitors 43 and 44 on the input side and the output side, and is separated for direct current and low frequency signals. However, feedback for DC and low frequency signals may be performed via the coil 45. These internal configurations are merely examples for the purpose of convenience of explanation, and the present invention is not limited thereto.

  An amplifier circuit 46 is also provided on the antenna element 12 side. The configuration of the amplifier circuit 46 is basically the same as that of the amplifier circuit 41, and the amplifier 47, the capacitors 48 and 49, and the coil 50 correspond to the amplifier 42, the capacitors 43 and 44, and the coil 45, respectively. The outputs of the amplifier circuits 41 and 46 are respectively connected to one ends of the core wires 31i and 32i of the coaxial cables 31 and 32, and the other ends of the core wires 31i and 32i are respectively connected to the selector 30. The outer conductors 31 o and 32 o of the coaxial cables 31 and 32 are commonly connected to the ground wiring 16 g of the amplifier 16. The ground wiring 16 g is connected to the metal foil 18 of the high frequency grounding member 17 through the connection line 19. The metal foil 18 is capacitively coupled with the conductive vehicle body 51 by interposing a layer of an electrically insulating coating film 52 therebetween. The selector 8 is provided with a switch 55 for switching one of the core wires 31i, 32i, 33i, 34i of the coaxial cables 31, 32, 33, 34 to be connected to the core wire 36i of the coaxial cable 36. The outer conductors 31o, 32o, 33o, 34o, 36o of the respective coaxial cables 31, 32, 33, 34, 36 are commonly connected to the DC ground 35.

  FIG. 3 shows a cross-sectional configuration of the high-frequency connection member 17. The high-frequency connection member 27 shown in FIG. 1 has an equivalent configuration. A coating 52 is formed on the body 51 of the conductor such as the pillar portion 6 for the purpose of anticorrosion and aesthetic improvement. The coating film 52 is electrically insulating and functions as a dielectric interposed between the metal foil 18 and the vehicle body 51. That is, the metal foil 18 and the vehicle body 51 serve as capacitor electrodes that sandwich the coating film 52, and have a low impedance for high-frequency signals, thereby enabling high-frequency grounding.

  The metal foil 18 is stuck on the coating film 52 by the adhesive 56. A terminal 57 is formed on the metal foil 18, and electrical connection to the connection line 19 is performed. In the terminal 57, the terminal conductor portion 58 is fitted into the cutout hole of the double-sided tape 59, and the whole is further protected with a resin 60.

  That is, the surface of the conductor portion of the vehicle body 51 is covered with an electrically insulating film such as the coating film 52, and the high-frequency ground members 17 and 27 are pasted on the coating film 52. Usually, the high-frequency grounding members 17 and 27 are attached to the exterior portion of the vehicle body 51 in which a conductor such as steel is covered with an electrically insulating film such as a coating film 52, thereby providing an electrically insulating film. Capacitive coupling can be generated between the conductive material and the high-frequency component through electrical grounding. The electrically insulating coating does not need to be peeled off, does not require a lot of work, and does not impair the corrosion resistance and aesthetic appearance, and can be grounded. In this embodiment, grounding in the vicinity of the antenna can be secured by attaching a metal foil to the body painted surface, so that installation workability is greatly improved. Further, since an amplifier is installed in the vicinity of the antenna, the S / N ratio deterioration due to cable loss is small, and since the coaxial cable and the amplifier are impedance matched, there is little noise induction on the cable, and the reception quality is hardly deteriorated.

  As described above, the vehicle-mounted antenna 1 according to the present embodiment includes the antenna elements 11 and 12; 21 and 22 attached to the windshield 4 that is a dielectric portion of the exterior portion of the vehicle body, High-frequency elements provided near the feeding points 15 and 25 of the antenna elements 11 and 12 and 21 and 22 and mounted on the pillar parts 6 and 7 which are conductor parts of the vehicle body and capacitively coupled to electrically ground the high-frequency component. It includes ground members 17 and 27 and amplifiers 16 and 26 that are provided in the vicinity of the feeding points 15 and 25 and amplify the high-frequency reception signal input from the feeding points 15 and 25.

  Since the antenna elements 11, 12; 21, 22 are attached to the dielectric part of the exterior part of the vehicle body, they are attached to an electrically insulating part such as a windshield, rear glass, side glass, roof glass, etc. It is possible to receive radio waves of high frequency signals while avoiding electrical influences such as. The high-frequency grounding members 17 and 27 are provided in the vicinity of the feeding points 15 and 25 of the antenna elements 11 and 12 and 21 and 22, and are attached to the conductor portions of the vehicle body to be capacitively coupled to electrically ground the high-frequency component. Therefore, it is possible to enhance the reception performance of the antenna by electrically grounding the conductor portion of the vehicle body in the vicinity of the antenna elements 11, 12; Since electrical grounding is performed by capacitive coupling, there is no need to make direct electrical contact, and even if the conductor part of the vehicle body is sufficiently painted with paint, there is no need for a process of peeling the coating, and it is easy It is possible to easily perform work associated with installation of an antenna on a vehicle that can be grounded, and perform appropriate ground connection to prevent a reduction in reception quality. The amplifiers 16 and 26 are provided in the vicinity of the feeding points 15 and 25 and amplify the high-frequency reception signals input from the feeding points 15 and 25. Therefore, the amplifiers 16 and 26 are weak high-frequency reception signals received by the antenna elements 11 and 12; Even if it exists, it can amplify in the position which is hard to receive the influence of the noise which generate | occur | produces in a vehicle, and can prevent receiving quality fall.

  The amplifiers 16 and 26 are directly connected to the feeding points 15 and 25 and the high-frequency grounding members 17 and 27. As a result, the amplifiers 16 and 26 are installed close to the feeding points 15 and 25 to the antenna elements 11 and 12 and 21 and 22 and the high-frequency grounding members 17 and 27, so that noise and the like are not easily mixed into the input side of the amplifier. The reception quality can be improved.

  FIG. 4 shows a schematic electrical configuration of an in-vehicle antenna 61 according to another embodiment of the present invention. In the present embodiment, parts corresponding to those in the embodiment of FIG. Although only one amplifier 16 side is shown and the other is omitted, it is a matter of course that it has the same configuration.

  In the present embodiment, the amplifier 16 is connected to the feeder lines 13 and 14 and the high-frequency grounding member 17 at the feeding point 15 via coaxial cables 62 and 63, respectively. The core wires of the coaxial cables 62 and 63 are connected to the feeder lines 13 and 14, respectively, and the outer conductors of the coaxial cables 62 and 63 are commonly connected to the high-frequency grounding member 17.

  FIG. 5 shows an electric circuit configuration of the present embodiment. Core wires 62i and 63i of the coaxial cables 62 and 63 are connected to the input sides of the amplifier circuits 41 and 46, respectively. The outer conductors 62 o and 63 o of the coaxial cables 62 and 63 are commonly connected to the installation wiring 16 g of the amplifier 16. In the present embodiment, the feeding point 15 to the antenna elements 11 and 12 and the high frequency grounding member 17 are connected to the input side of the amplifier 17 via the coaxial cables 62 and 63, so that the installation position of the amplifier 16 can be easily selected. be able to.

  In the embodiment of FIGS. 1 and 4, the amplifiers 16 and 26 output the amplified high-frequency reception signals via the coaxial cables 31, 32, 33, and 34, and the coaxial cables 31, 32, 33, and 34 receive the high-frequency signals. In the vicinity of being connected to the selector 30 or the receiver 40 as an in-vehicle device that performs signal processing, the DC ground 35 electrically grounds the DC components of the amplifiers 16 and 26 to the vehicle body. This is because the outer conductors 31o, 32o, 33o, 34o of the coaxial cables 31, 32, 33, 34 are commonly connected to the DC ground 35. The electrical grounding to the vehicle body regarding the DC component of the amplifiers 16 and 26 is performed in the vicinity where in-vehicle devices such as the selector 8 and the receiver 9 that process the high-frequency reception signals amplified by the amplifiers 16 and 26 are mounted on the vehicle. Such an in-vehicle device is installed in a vehicle interior or the like, and can easily be electrically grounded to the vehicle body.

  A plurality of antenna elements 11, 12; 21, 22 are connected to the amplifiers 16, 26, respectively, and the high frequency grounding members 17, 27 are common to the plurality of antenna elements 11, 12; Grounding is performed. Since the high frequency components based on the capacitive coupling to the conductor portion of the vehicle body 51 by the high frequency grounding members 17 and 27 can be commonly performed on the plurality of antenna elements 11, 12; , 27 can be reduced, and the work required for mounting can be easily performed.

  In the embodiment of FIGS. 1 and 4, the film antennas 2 and 3 are provided with a plurality of antenna elements 11 and 12; 21 and 22. Of course you can get it. Of course, only one film antenna 2 or 3 may be used. On the other hand, when a plurality of film antennas 2 and 3 are used or a plurality of antenna elements 11, 12, 21, 22 are provided in each film antenna 2, 3, diversity-type reception can be performed by selectively switching. .

  FIG. 6 shows a schematic electrical configuration of a vehicle-mounted antenna 71 that can suitably perform diversity-type reception as still another embodiment of the present invention. In the present embodiment, portions corresponding to the embodiment of FIG. 1 or FIG. 4 are given the same reference numerals, and redundant description is omitted. Also in this embodiment, the configuration on one antenna element 11 and 12 side is shown, and the other antenna element 21 and 22 side is omitted, but it is a matter of course that it has a substantially equivalent configuration. In this embodiment, the switch 75 is built in the input side of the amplifier 76, the feed lines 13 and 14 from the antenna elements 11 and 12 are switched and amplified by the amplifier circuit 77, and the amplified output is derived to the coaxial cable 78. it can. The coaxial cable 78 is connected to the selector 80 together with a control line 79 that controls switching of the switch 75. The selector 80 includes a switch 81 and switches between the coaxial cable 78 and the coaxial cable 82 from another amplifier, and inputs the signal to the receiver 9 in FIGS. 1 and 4 to constitute a diversity receiver.

  That is, in the present embodiment, a plurality of antenna elements 11 and 12 that are attached to the windshield 4 or the like, which is a dielectric portion of the exterior portion of the vehicle body 51, are provided close to the feeding point 15, and the plurality of antennas. A high-frequency grounding member 17 that is provided near the feeding point 15 of the elements 11 and 12, is mounted on the conductor portion of the vehicle body 51 and is capacitively coupled, and performs common electrical grounding regarding high-frequency components, and is provided near the feeding point 15. The amplifier 76 that amplifies the high-frequency reception signal input from the feeding point 15, the switch 75 that is provided in the amplifier 16 and selects the antenna elements 11 and 12 that amplify the high-frequency reception signal, and the high-frequency amplified by the amplifier 76. Processing the received signal and remotely controlling the switch 75 to provide an antenna element with good reception quality for the high frequency received signal. The diversity receiving device and a selector 80 and a receiver 9 as a selective reception means for selecting the door 11.

  Such a diversity receiving apparatus has the same characteristics as the above-described in-vehicle antennas 1 and 61, and the switch 75 is provided in the amplifier 76, and selects the antenna elements 11 and 12 that amplify the high-frequency reception signal. The high frequency signal can be amplified by one amplifier 76 for the plurality of antenna elements 11 and 12. In the selector 80 and the receiver 9 as selective receiving means, the high frequency received signal amplified by the amplifier 76 is processed, and the switch 75 is remotely controlled to receive the antenna element 11 having a good reception quality regarding the high frequency received signal. Since 12 is selected, even if the reception environment changes as the vehicle moves, it is possible to select the antenna elements 11 and 12 with good reception quality and continue reception.

  In this embodiment, a combination similar to the combination of the plurality of antenna elements 11 and 12 and the amplifier 76 is provided at a different location on the exterior of the vehicle body 51, and the coaxial cables 78 and 82 are switched by the switch 81 of the selector 80. Thus, it is possible to select a plurality of amplifiers and an antenna element connected to the amplifier. By doing so, a combination of a plurality of antenna elements and amplifiers are arranged at different locations on the exterior of the vehicle body 51, the amplifier is selected to select the location of the antenna, and the plurality of antennas provided at the selected locations Antenna elements can be selected to obtain good reception quality.

  Further, as shown in FIG. 6, when the amplifier 76 is provided with a switch 75 for selecting the antenna elements 11 and 12 for amplifying the high-frequency received signal from among the plurality of antenna elements 11 and 12, the above-mentioned Not only can it be used as a diversity receiver, but it can easily receive different frequency bands by changing the shape of the antenna elements 11 and 12, and even if there is only one signal line from which the output of the amplifier 76 is derived. The received signals from the antenna elements 11 and 12 can be selected and transferred.

1 is a block diagram showing a schematic electrical configuration of a vehicle-mounted antenna 1 that is an embodiment of the present invention. FIG. 2 is an electric circuit diagram of a portion related to an amplifier 16 in FIG. 1. It is sectional drawing which shows the structure about the mounting part of the high frequency installation member 17 of FIG. It is a block diagram which shows schematic electrical structure of the vehicle-mounted antenna 61 which is other embodiment of this invention. FIG. 5 is an electric circuit diagram of a portion related to the amplifier 16 of FIG. 4. It is a partial electrical circuit diagram of the vehicle-mounted antenna 71 which is further another form of implementation of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,61,71 In-vehicle antenna 2,3 Film antenna 4 Windshield 6,7 Pillar part 8,80 Selector 9 Receiver 10,20 Film board 11,12; 21,22 Antenna element 15,25 Feed point 16,26 , 76 Amplifier 17,27 High frequency grounding member 18,28 Metal foil 19,29 Connection line 31,32,33,34,36,63,64,78,82 Coaxial cable 35 DC ground 37,79 Control line 41,46, 77 Amplifier 55, 75, 81 Switch 56 Adhesive

Claims (9)

An antenna element mounted on a dielectric portion of the exterior of the vehicle body;
A high-frequency grounding member that is provided in the vicinity of the feeding point of the antenna element, is mounted on a conductor portion of the vehicle body, is capacitively coupled, and performs electrical grounding related to a high-frequency component;
An in-vehicle antenna comprising an amplifier provided in the vicinity of the feeding point and amplifying a high-frequency reception signal input from the feeding point.   The in-vehicle antenna according to claim 1, wherein the amplifier is directly connected to the feeding point and the high-frequency grounding member.   The in-vehicle antenna according to claim 1, wherein the amplifier is connected to the feeding point and the high-frequency grounding member via a coaxial cable. The amplifier outputs the amplified high frequency received signal via a coaxial cable,
The electrical grounding related to the DC component of the amplifier is performed on the vehicle body in the vicinity of the coaxial cable being connected to a vehicle-mounted device that processes a high-frequency received signal. The vehicle-mounted antenna described. The conductor portion of the vehicle body is covered with an electrically insulating coating on the surface,
The on-vehicle antenna according to any one of claims 1 to 4, wherein the high-frequency grounding member is a metal thin plate member affixed on the electrically insulating film. A plurality of antenna elements are connected to the amplifier,
The in-vehicle antenna according to any one of claims 1 to 5, wherein a common ground of a high-frequency component is performed on the high-frequency grounding member with respect to the plurality of antenna elements.   The vehicle-mounted antenna according to claim 6, wherein the amplifier includes a switch for selecting an antenna element for amplifying a high-frequency received signal from the plurality of antenna elements. A plurality of antenna elements that are attached to the dielectric portion of the exterior portion of the vehicle body and provided close to the feeding point;
A high-frequency grounding member provided in the vicinity of a feeding point of the plurality of antenna elements, mounted on a conductor portion of a vehicle body, capacitively coupled, and electrically grounding a high-frequency component in common;
An amplifier that is provided in the vicinity of the feeding point and amplifies a high-frequency reception signal input from the feeding point;
A switch provided in the amplifier for selecting an antenna element for amplifying a high-frequency received signal;
Diversity comprising: selective reception means for processing a high-frequency received signal amplified by the amplifier and remotely controlling the switch to select an antenna element having good reception quality regarding the high-frequency received signal Receiver device. The combination of the plurality of antenna elements and the amplifier is provided at different locations on the exterior portion of the vehicle body,
9. The diversity receiving apparatus according to claim 8, wherein the selection receiving unit performs selection of the plurality of amplifiers and selection of an antenna element connected to the amplifiers.

Images