KR200409080Y1 - Antenna for Automobile - Google Patents

Abstract

The present invention relates to a vehicle antenna device for smooth radio wave reception of communication services such as digital multimedia, television receivers, radios, and other telematics, mobile communication, etc. in a vehicle that is running or stopped. An external capacitive induction panel mounted on the vehicle and transmitting the radio signal received from the helical antenna to a receiver in the vehicle, and a capacitive induction panel mounted opposite to the external capacitive induction panel inside the glass of the vehicle body and receiving the induced signal. And an internal capacitive induction panel including an equivalent circuit and an amplifier circuit for amplifying a received signal passing through the equivalent circuit.

Car Antenna, Capacitive Induction Panel, Capacitive Coupler

Description

Antenna device for vehicle {Antenna for Automobile}

1 is a mounting state diagram when a vehicle antenna is mounted on a vehicle using a conventional mounting hole.

2 is a mounting state diagram when a vehicle antenna is mounted on a vehicle using a conventional magnet;

3 is a basic structural diagram of a coupling antenna applied to the present invention.

4 is a circuit diagram of an amplifier module applied to the present invention.

5 is a capacitance and equivalent circuit diagram according to the physical form of the capacitive inductor applied to the present invention.

6 is an impedance matching relationship diagram in a Smith diagram.

7 is a circuit diagram of compensating for an impedance shift of an induction panel.

8 is a single circuit board structure diagram of a capacitive induction metal plate and an amplifier circuit.

Figure 9 is a cross-sectional view showing a screw bolt coupling method of the circuit board and the case.

10 is a cross-sectional view of the circuit board and the case for improving the adhesion of the capacitive induction panel.

11 is a compression pad and a circuit layout of a circuit board.

12 is a three-dimensional model diagram of a backside pad adhesive structure to improve capacitive panel adhesion.

Figure 13 is an antenna form in the present invention.

14 is a view showing an example of a panel contact method according to an embodiment of the present invention.

15 is a state in which the antenna device according to the present invention is mounted on the vehicle.

<Explanation of symbols for the main parts of the drawings>

110... Helical antenna

130... External capacitive induction panel

140... Internal capacitive induction panel

170... Body

210... Amplification circuit

310... Equivalent circuit

The present invention relates to an antenna device for a vehicle, and more particularly, to a vehicle antenna device for smooth radio wave reception of a broadcasting service such as a digital multimedia, a television receiver, a radio, and a communication service such as telematics and mobile communication in a traveling or stationary vehicle. It is about.

The need for technological advancement and entertainment through advanced information and visual media is increasing day by day. Therefore, even in the environment of driving or transport in a vehicle, such a desire is increasing, and the application rate of the A / V system of the produced / shipped vehicle is increasing day by day. Key to vehicle applications is high performance and ease of installation.

In general, in order to receive radio from a vehicle, a manual or automatic antenna having a length of about 70 cm around the front or rear fenders has been used to avoid the roof of the vehicle. The situation is developing by combining the antenna for the TV. In this case, however, a multi-receiver antenna method is required to compensate for the poor directivity and reception performance of the TV antenna, and an external antenna is inevitably installed when the receiver is mounted after shipping.

According to the antenna theory, in the case of sedans and RV vehicles, the most ideal antenna method for receiving radio or TV broadcasts or other wireless communication is to install a rod antenna on the roof panel of the vehicle. . However, in the frequency band below the VHF, the antenna length which is proportional to the wavelength is relatively long, which damages the appearance of the vehicle, and the mounting difficulty that requires the feed-thru hole in the vehicle body for antenna fixing and coaxial cable connection. This happens.

The antenna system mainly applied to a vehicle is based on a classic rod antenna. In order to make the most of the ground effect, the main mounting method of the rod-type antenna is generally installed perpendicular to the roof of the vehicle. For fixing the rod-type antenna, a mounting hole or a magnet is used to fix the rod-type antenna. After wiring, it is common to use a gap around it.

Therefore, in the case of a system using an external antenna, a load antenna, a coupling portion with a vehicle body, and a transmission line are necessary parts, and an amplifier may be additionally used for improved performance.

1 is a mounting state diagram when a vehicle antenna is mounted on a vehicle using a conventional mounting hole.

As shown in the drawing, a mounting hole 15 is formed in a part of the vehicle body surface 11 on which the antenna 13 is mounted, and a part of the antenna 13 is inserted into the mounting hole 15, and then the inside The antenna 13 is firmly fixed to the coupling mechanism 12. In this case, there is a deformation and damage of the internal wiring 14 due to the damage of the vehicle body, which requires a lot of research and devising from the design stage of the vehicle.

However, such an antenna mounting method has a disadvantage in that mounting is arbitrarily installed in a vehicle in which mounting holes are not prepared, which may damage watertightness characteristics and stability of the vehicle body.

FIG. 2 is a state diagram of a vehicle antenna mounted using a magnet. As shown in FIG. 2, the antenna 21 may be fixed to the vehicle body surface 24 by using a magnet 22 of about several thousand Gauss. , A problem of scratching of the vehicle body surface 24 due to contact with the magnet surface during mounting and dismounting, and the connection wiring 23 from the antenna 21 to the inside of the vehicle body protrudes out of the car, thereby damaging the aesthetics. There is this. In addition, since the rubber of the door gap is used as the through hole of the connection wiring (cable), there is a disadvantage that the watertightness also becomes a problem.

As a method for overcoming the disadvantages caused by the antenna mounting structure as described above, an antenna that transmits a signal using a coupling effect of an electromagnetic signal by placing a metal surface inside and outside the glass surface of the vehicle is used. It also became.

In this case, since the signal is transmitted through the glass part of the vehicle, there is no need for a separate wiring device for signal connection between the inside and the outside of the vehicle body. However, since it is used only for signal transmission in a simple structure, relative reception performance is deteriorated due to signal attenuation and narrow band characteristics, which is applied only to a part of the personal mobile communication service (PCS) and cellular phone bands. It is true.

Therefore, recently, in the case of antennas applied to a vehicle, due to the limited mounting space of the vehicle body, antennas in the form of metal wires similar to heating wires are often designed in rear glass, side glass, and the like. The trend is to use short pole antennas with shorter physical lengths than suitable lengths.

Since these antennas have a lower gain than a reference antenna, an amplifier module may be used to increase reception sensitivity. However, even when the amplifier is applied, special considerations such as minimizing losses due to impedance matching and preventing signal-to-noise ratio deterioration are necessary, and the system has to be complicated, such as the installation space, the body connection structure, and the wiring design.

In this regard, the present invention is proposed to solve various problems occurring when the conventional antenna is mounted on a vehicle.

It is an object of the present invention to provide a vehicle antenna for smooth radio wave reception of a communication service such as digital multimedia, a television receiver, a radio, and a telematics, a mobile communication, etc. in a traveling or stationary vehicle.

Another object of the present invention is to provide an antenna for a vehicle for smoothly receiving a broadcast communication service of a very high frequency wave (VHF) or an ultra high frequency wave (UHF) band such as terrestrial digital multimedia broadcasting (DMB) in a driving or stationary vehicle.

In the present invention, in order to overcome the difficulties of the mounting method, a mounting method using a vehicle body glass surface is used. This method has the advantage that the signal lines can be eliminated since the electromagnetic signal received by the antenna is transmitted from the outside of the vehicle body to the inside through the metal surface, thereby simplifying the wiring, but the structural shape of the coupling panel on both sides Because the capacitance value is very small, it inevitably leads to a loss on the transmission line. In particular, the loss effect is more severe when the frequency is relatively low. In order to alleviate this drawback, the present invention minimizes transmission signal loss by using capacitive induction panels inside and outside the glass surface.

In addition, an amplifier module is used to improve the strength of the received signal. When the amplifier is used, it is necessary to compensate the transmission loss of the coupler, but not to deteriorate the signal-to-noise ratio of the system to increase the overall reception performance of the antenna system. This improves the complexity of the structure, which not only secures the characteristics of the amplifier itself, but can also cause potential performance degradation.

Particularly, in the present design, a capacitive induction panel and an amplification circuit are designed on one circuit board to perform both capacitive coupling and function as an amplifier for a signal from an external antenna in a module inside the vehicle body. It has the advantage of maintaining a small size. Here, the capacitive induction panel was interpreted as part of the circuit to design the amplifier, thereby reducing the transmission loss and ensuring the performance of the amplifier.

Hereinafter, described in detail with reference to the accompanying drawings a preferred embodiment of the present invention. Prior to describing the present invention, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, a detailed description thereof will be omitted.

A general antenna system is composed of an antenna and a signal line, and the antenna element serves to receive the first radio signal and is designed in various forms, and the signal line transmits the radio signal received by the antenna to the receiver. Done.

In the present invention, a capacitive coupler using the windshield of the vehicle as a dielectric is inserted between the antenna and the signal line as a means for introducing a signal from the outside to the inside of the vehicle, and this type of antenna has been used for mobile phones in the past.

3 is a schematic view of a coupling antenna applied to the present invention, and as shown in the figure, the exterior of the vehicle body surface 170 is an antenna 110, a switching unit 120, and an external capacitive panel 130, which is a coupling panel. ) And an inner side is composed of an internal capacitive panel 140 and a signal line 150 which are couplings. In addition, the mounting portion 160 for mounting is further included, and a case for protecting the device may be further provided.

The antenna device has been basically used as a passive antenna without using a separate amplifier, but the antenna element is long (1/4 wavelength) long and exposed to the outside of the vehicle to damage the exterior of the vehicle and prevent damage during automatic car wash. In order to avoid the inconvenience of manually removing the antenna.

Therefore, in the present invention, a short circuit antenna having a helical structure is used, and an amplification circuit is added to compensate for signal loss due to the short circuit. Unlike conventional amplifier circuits, however, careful consideration must be given to designing the amplifier to meet capacitive induction panel applications.

Therefore, in using the coupling structure and the amplifier circuit together, it is necessary to replace the electrical characteristics of the coupling panel with an equivalent circuit of a part of the amplifier circuit.

4 illustrates an amplification circuit applied to the present invention.

Here, reference numeral 210 denotes an amplifier circuit, reference numeral 211 denotes a matching and filtering unit for impedance matching and signal filtering, and reference numeral 212 denotes an amplifier for amplifying a signal received from an antenna to a predetermined level.

Therefore, when the coupling panel is applied to the glass surface of the vehicle, the equivalent circuit of capacitance may be replaced with the input terminal of the amplifier circuit.

FIG. 5 illustrates a capacitive and equivalent circuit 310 according to the physical form of a capacitive coupler applied to the present invention.

As shown therein, the capacitance value of the external capacitive induction panel 130 installed on the glass surface 170 of the vehicle can be calculated, the glass thickness (D) of the vehicle 3.6 mm, the dielectric constant of the glass 7.5 and the external capacitive It is determined by the width of the induction panel 130. However, since the physical size of the external capacitive induction panel 130 is subject to mounting constraints, the physical size of the external capacitive induction panel 130 should be determined as a reasonable size (W, L) in consideration of mounting property and appearance. Therefore, the size of the external capacitive induction panel 130 may be determined to about 20 ~ 30mm. The capacitance value C of the external capacitive induction panel 130 that satisfies this condition has a value of about 7 to 16 pF by calculation and measurement. In general, however, the capacitance present at the input of the amplifier will result in signal loss at lower frequencies.

The equivalent circuit 310 has an inductor L, a resistor Rs connected in series with the inductor L, a resistor Rp connected in series with the resistor Rs, and the resistor Rp in parallel. It is implemented with a capacitance C that is connected to implement the filtering circuit.

6 is an impedance matching relationship diagram of a general Smith diagram.

Considering this phenomenon in terms of impedance matching, impedance mismatch occurs due to the small capacitance value of the external capacitive panel 130 whose input impedance of a circuit matched to 50 Ω is a coupling panel, which is 195 MHz in the diagram of FIG. 6. Based on (terrestrial DMB 174 ~ 216MHz or the center band of TVs CH 8 & 12), when the capacitance of the coupling panel is 12pF, the capacitance reactance (Xc) is 67.88, and the matched center (matching point) as shown in FIG. (MP) to the right and lower fluctuation range (VA), which indicates an impedance mismatch.

In general, the input part of the amplifying circuit has a circuit part combined with a L (inductor) and a C (capacitor) for realizing a band pass filter and a stop band filter of a specific band. What is needed is a method of designing the input impedance including the panel to match. In order to implement this, there are a method of changing an existing device value to move to the design area DA and a method of moving to the variation area VA to move to a parallel inductor and then to DA to match. The circuit composed of the latter of these two methods is shown in FIG.

7 is a circuit diagram of compensating for an impedance shift of a capacitive induction panel.

An important principle in determining the size of the external capacitive panel 130, which is the coupling panel, is to make the external capacitive panel 130, the coupling panel, as large as possible under the limited conditions, and to increase the capacitance value so that it can be compensated in the amplifier. It should have a capacity value. With this arrangement of external capacitive panels, impedance compensation techniques can be implemented to successfully induce electromagnetic signal and act as an amplifier on one substrate.

8 is a single circuit board structure of a capacitive induction metal plate and an amplifier circuit.

The signal received by the antenna is guided to the metal surface printed on the circuit board 200 of the module inside the vehicle body 170 through the external capacitive panel 130 which is the coupling panel. The signal thus induced is connected to the first stage of the amplifying circuit 145 mounted on the same printed circuit board 200 and amplified and output to the output signal line. That is, the signal induced by the external capacitive induction panel 130 on the upper side is transmitted to the opposite side of the circuit board 200 and is transmitted to the input terminal of the amplifying circuit 145 disposed on the lower side. Since the amplifier circuit 145 necessarily requires the ground of the circuit, the ground is provided around the circuit and the rear surface where the circuit is arranged. At this time, since the ground of the circuit and the coupling panel 140 are located on the same surface, it is essential to avoid interference with each other.

In addition, the adhesion between the vehicle body 170 and the panel is very important in a structure in which the surface of the panel is in contact with the vehicle body 170 which is glass. The capacitance capacitance value of the coupling panel mentioned above assumes that both panels of the minimum design area are in close contact with the glass surface, and the capacity reduction caused by the air gap leads to a performance loss by generating a signal loss. Substantially, in the method of fixing the circuit board PCB to the case 161, since the processing of the substrate hole is not free, as shown in FIG. 9, the coupling method using the screw bolt 181 is inferior in adhesion due to protrusion of the head. It is unavoidable to decrease performance.

The form devised to solve this problem is shown in FIG. A structure using a double-sided adhesive compressed sponge pad 182 on the back of the panel is devised without using a screw bolt fixing method. The compressed sponge pad 182 pushes the circuit board 200 on the upper surface due to the repulsive property, thereby bringing the induction panel closer to the glass. And the intaglio (Hole) 162 formed in a grid shape of the case 161 serves to increase the resilience retention period of the sponge pad 182.

An important problem to be solved here is that the amplification circuit and the adhesive pad are located on the same plane. In order to maintain the adhesion area of the adhesive pad and to satisfy the layout of the device for satisfying the characteristics of the RF amplification circuit, the division of the area that satisfies at the same time is an important problem. The problem can be solved by molding the shape into a 'c' shape.

Therefore, in consideration of the fact that it is impossible to arrange a component having a height, the coupling panel has a shape of an antenna installation structure to maintain the shape of a transmission line and ground for maintaining the characteristics of the RF amplifier and to secure an adhesive surface for assembly stability. 12 is preferably implemented as shown in FIG. 13.

In addition, as shown in FIG. 14, in order to improve the adhesion of the external capacitive panel 130, which is a coupling panel on the side of the antenna 110, an elastic plate spring 131 structure is applied to closely adhere the metal plate to the glass surface body 170. Can be fixed.

Since the mounting position in the vehicle is mounted using the glass surface of the vehicle body 170, the rear glass, the wind shield glass, or the side glass in the case of an RV / SUV vehicle ) Can also be mounted and an example of mounting is shown in FIG. 15.

The present invention is not limited to the above-described specific preferred embodiments, and any person having ordinary skill in the art to which the present invention pertains may make various modifications without departing from the gist of the present invention claimed in the claims. Of course, such changes will fall within the scope of the claims.

According to the present invention as described above, in the method for transmitting the radio signal received from the outside of the vehicle to the receiver in the vehicle to increase the simplicity of the structure of the structure, and insert the amplifier in the coupling panel for stable radio reception performance, Using a single substrate has the effect of simplifying the structure and reducing the size compared to the conventional method.

In addition, it is possible to ensure the ease of vehicle mounting and stable maintenance of performance, and also has the advantage of lowering the manufacturing cost.

Claims (5)

An external capacitive induction panel 130 mounted outside the glass of the vehicle body 170 and transmitting a radio signal received from the helical antenna 110 to a receiving end in the vehicle; It is mounted inside the glass of the vehicle body 170 to face the external capacitive induction panel 130 and passes through the equivalent circuit 310 and the equivalent circuit 310 of the capacitive induction panel receiving the induced signal. Vehicle antenna device, characterized in that consisting of an internal capacitive induction panel (140) comprising an amplifying circuit (210) for amplifying a received signal. The method of claim 1, wherein the internal capacitive induction panel 140, The equivalent circuit 310 and the amplifier circuit for amplifying the received signal 210 is a vehicle antenna device, characterized in that formed integrally on a single circuit board (200). The method of claim 1 or 2, wherein the high-density sponge pad (182) having a double-sided adhesive to increase the adhesion between the internal capacitive induction panel 140 and the glass (dielectric) surface of the vehicle body 170 Vehicle antenna device, characterized in that for coupling the circuit board 200 to the case (161) in which the internal capacitive induction panel is built. The method of claim 3, wherein the fixing portion of the circuit board 200 of the case 161 is processed by the lattice 162 to minimize the compression set or the elastic damage of the sponge pad 182 while maintaining the adhesion strength. Antenna device. 3. The equivalent circuit (310) according to claim 2, wherein the equivalent circuit (310) includes an inductor (L), a resistor (Rs) connected in series with the inductor (L), a resistor (Rp) connected in series with the resistor (Rs), Vehicle antenna device, characterized in that implemented in the capacitance (C) connected in parallel with the resistor (Rp).

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