CN1205118A - Multiple frequency antenna - Google Patents

Abstract

For the purpose of receiving GPS signals stably and installing it at any position on the vehicle body, a GPS antenna 10 is built in the cover 2, and an adjustment circuit board 9 and the like are built in at the same time. The antenna unit 1 is connected to the adjustment circuit board 9 . Setting and adjusting the circuit board 9 etc. upright can improve the grounding effect of the GPS antenna 10, and at the same time, no adverse effect will be produced even if the GPS satellite is at a low elevation angle. Since the antenna unit 1 is installed obliquely with respect to the vertical line, there is no adverse effect even if the GPS satellite is at a low elevation angle.

Description

Antennas for multiple frequencies

technical field

The present invention relates to an antenna capable of receiving 4-band signals of a portable wireless phone, FM broadcast band, AM broadcast band, and GPS band, especially a roof antenna suitable for installation on the roof of a car body.

Background technique

There are many types of antennas installed on the car body, but if the antenna is installed on the roof at the highest position of the car body, the reception sensitivity can be improved, so people have always preferred the roof antenna installed on the top. In addition, since FM radio and AM radio are generally installed in the car, it is easy to use antennas that can receive both FM broadcast bands and AM broadcast bands. Therefore, top antennas that can receive two broadcast bands at the same time have become popular.

In addition, car navigation systems or portable wireless phones using GPS (Global Positioning System) are becoming more and more popular recently, and the GPS antenna used in the car navigation system and the portable wireless phone antenna used in the portable wireless phone are installed in the car. physically.

Furthermore, in the case of having a keyless door lock system in which a door lock switch is remotely operated wirelessly, an antenna for a keyless door lock is attached to the vehicle body.

However, it is unsightly to install such various antennas independently on the vehicle body, and maintenance and installation operations are complicated. Therefore, it is desirable to use a single antenna to receive portable wireless telephone frequency bands, FM broadcast frequency bands, AM broadcast frequency bands, and GPS frequency bands. , and multi-frequency antennas for keyless entry lock frequency bands.

FIG. 7 shows a configuration example of such a multi-frequency antenna disclosed in JP-A-6-132714 as a prior proposal. In Fig. 7, the freely retractable rod antenna 101 is a 3-band shared antenna that can receive the portable radiotelephone frequency band, the FM broadcast frequency band, and the AM broadcast frequency band, the planar radiator 102 is a GSP antenna for receiving GSP signals, and the loop radiator 103 is an antenna for a keyless door lock that receives a keyless door lock signal.

These various antennas are provided on the main body 100 . A metal plate 104 made of metal is provided on the upper part of the main body 100 , and a planar radiator 102 and a circular radiator 103 are formed on the metal plate 104 by a dielectric layer. Since the metal plate 104 functions as a ground plane, the planar radiator 102 and the loop radiator 103 work as a microstrip antenna. Furthermore, a protective cover 105 is formed on the planar radiator 102 and the annular radiator 103 .

However, in the above-mentioned multi-frequency antenna, when storing the freely retractable rod antenna 101 so that it does not protrude from above, it is necessary to have a storage space for accommodating the rod antenna 101 in the internal space of the mounting part where the multi-frequency antenna is mounted. Therefore, although a multi-frequency antenna can be mounted on a trunk lid or a fender of a vehicle body, it cannot be mounted on a position where there is no storage space such as a roof.

However, it is well known that the elevation angles of radio waves transmitted from GSP satellites are often low. However, when the multi-frequency antenna is mounted on the trunk lid or the fender, radio waves from the satellite may be blocked by the vehicle body due to the position of the GSP satellite.

In addition, if the planar radiator 102 serving as a GPS antenna is surrounded by the annular radiator 103 for keyless entry locks, as described above, the elevation angle of GPS radio waves is often low, so there may be differences depending on the position of the GPS satellites. A problem that significantly affects GPS antenna sensitivity.

Therefore, an object of the present invention is to provide a multi-frequency antenna that can be installed on a high position such as a roof of a vehicle body without a storage space without affecting the operation of the GPS antenna.

disclosure of invention

In order to achieve the above object, the multi-frequency antenna of the present invention has a whip-shaped antenna unit capable of receiving 3 bands of AM broadcast band, FM broadcast band, and portable wireless telephone band; and this antenna unit can be installed, and at least A circuit board with an adjustment device, a frequency division device and an amplification device, and an antenna case for a GPS antenna; the antenna case is composed of a conductive base and a cover embedded in the base, and the above-mentioned circuit board is fixed upright on the base , and at the same time, a GPS antenna receiving part for installing a GPS antenna is integrally formed on the above-mentioned base and orthogonally to the above-mentioned circuit board.

In addition, the above-mentioned multi-frequency antenna may be fixed on the top of the vehicle body, and the above-mentioned GPS antenna storage part is formed by a protrusion surrounding the entire outer circumference of the above-mentioned GPS antenna, and the above-mentioned GPS antenna storage part is shielded and arranged on the back side of the above-mentioned GPS antenna. circuit board.

Also, the antenna unit is tilted approximately 20° to 35° from the upright position.

According to the present invention, since the antenna storage section is not required under the multi-frequency antenna, when it is mounted on a vehicle body, it can be mounted on a high place such as a roof where there is no storage space. Therefore, it is possible to prevent the GPS radio wave received by the GPS antenna from being blocked by an attached body such as a vehicle body, and thus preventing the GPS radio wave from being received.

In addition, since the circuit board is arranged orthogonally to the GPS antenna, the grounding effect of the GPS antenna can be improved. Furthermore, even if the GPS radio waves come at a low elevation angle, since the circuit board is installed upright and the antenna unit is arranged obliquely, the influence on the GPS antenna can be prevented as much as possible.

Furthermore, since the circuit board for signal processing of the GPS antenna is shielded, the GPS antenna can be stably operated.

A brief description of the drawings

FIG. 1 is a diagram showing a part of an exploded perspective view showing the configuration of an embodiment of a multi-frequency antenna according to the present invention.

Fig. 2 is a diagram showing another part of an exploded perspective view showing the configuration of an embodiment of the multi-frequency antenna of the present invention.

3 is a cross-sectional view and a front view showing the structure of an embodiment of the multi-frequency antenna of the present invention.

Fig. 4 is a diagram showing the configuration of a cover and a base of the multi-frequency antenna of the present invention.

FIG. 5 is a diagram showing the structure of the circuit board bracket of the multi-frequency antenna of the present invention.

Fig. 6 is a diagram showing the structure of the grounding bracket of the multi-frequency antenna according to the present invention.

FIG. 7 is a diagram showing the configuration of a conventional multi-frequency antenna.

Best Mode for Carrying Out the Invention

Figures 1 and 2 show exploded oblique views of the composition of the embodiment of the multi-frequency antenna of the present invention.

In these two figures, the antenna unit 1 is composed of a linear member 1-1, a frictional wind noise prevention device 1-2 wound helically on the member 1-1, and some kind of flexible material such as rubber series. The antenna base 1-3 is formed by molding a synthetic resin. In this antenna substrate 1-3, a trap coil can be inserted and connected to the component 1-1. A coil spring for preventing breakage as a part of the antenna unit 1 may also be provided inside the antenna base 1-3.

A fixing screw 1 - 4 for mounting the antenna unit 1 on the cover 2 is protrudingly provided from the lower end of such an antenna unit 1 .

And, set the electrical length from the top of the antenna unit 1 to the fixing screw 1-4 as the antenna base part to about 1/4 wavelength of the FM broadcast frequency band, and set the electrical length from the fixing screw 1-4 to the inside of the antenna base 1-3. The electrical length of the lower end of the notch coil is set to about 1/4 wavelength of the portable radiotelephone frequency band.

On the cover 2 that fixes the antenna unit 1, there is provided a waterproof and sealed component connection fitting 2-7 for tightening the fixing screw 1-4 provided at the lower end of the antenna unit 1. In addition, the structure of this cover 2 is that it is fitted on the base 3 shown in FIG. 2 which is made of metal or is plated with conductive plating on the whole surface.

On base 3, be fixed with the circuit board bracket 12 that is made by processing metal plate, on this circuit board bracket 12, be fixed with the amplifier circuit board 8 that is assembled with amplifying circuit vertically with respect to circuit board bracket 12 and be assembled with Adjustment circuit board 9 for regulator or frequency divider. On the adjustment circuit board 9, the connection piece 7 for electrically connecting the antenna unit 1 is fixed by soldering; the connection screw inserted into the component connection fitting 2-7 arranged on the top of the cover 2 is tightened through the waterproof gasket 5 On the connecting piece 7, the component connection accessories 2-7 can be electrically connected with the connecting piece 7.

A housing portion 3 - 10 for housing the rectangular GPS antenna 10 is formed on the base 3 , and the GPS antenna 10 is accommodated in the housing portion 3 - 10 via a wave-shaped wave spring 11 . And when the cover 2 is fitted and fixed on the base 3, the GPS antenna 10 can be held in the receiving portion 3-10 by pressing the GPS antenna 10 toward the base 3 with the pressing protrusion formed on the inside of the cover 2.

In addition, in the state where the cover 2 is fitted on the base 3, the cover can be fixed to the base by tightening four fixing screws 14 from the bottom surface of the base 3 to the screw holes formed on the inner side of the cover 2. 3 on. Furthermore, a fixing screw 3-9 protruding from the bottom surface of the base 3 is inserted into a mounting hole formed on a mounted body such as a vehicle body, and an O-ring 13 for waterproofing is embedded on the fixing screw 3-9. .

In addition, the lower end of the base 3 is embedded with a cushioning washer 15 made of a flexible material, thus, when the nut 16 is tightened on the fixing screw part 3-9 protruding from the back side of the mounted body, the When the multi-frequency antenna is mounted on the mounted object, it is possible to prevent damage to the mounted object, etc.

In addition, a groove portion is formed on the edge of the lower end portion of the cover 2, and a waterproof gasket 6 is fitted into the groove so that the cover 2 and the base 3 can be waterproofly fitted.

And, the power cord 18, the GPS cable 19, the telephone cable 20, and the radio cable 21 are introduced into the mounted body through the through hole formed on the base 3 and the cylindrical fixing screw portion 3-9. inside.

In this case, the grounding part of the cable 20 for the telephone and the cable 21 for the radio is electrically connected to the grounding bracket 17, and the two cables are bundled together, and are bundled together with the power cord by the binding member 22. In addition, connectors for connection are respectively provided at the tips of the cables and wires.

FIG. 3( a ) shows a cross-sectional view of the multi-frequency antenna of the present invention constructed in this way, and FIG. 3( b ) shows a front view thereof. In addition, FIG. 4( a ) shows the structure inside the cover 2 , and FIG. 4( b ) shows the structure seen from the top of the base 3 . Hereinafter, the multi-frequency antenna of the present invention will be described with reference to these figures.

As shown in these figures, the connecting screw 4 inserted into the component connecting fitting 2 - 7 integrally formed with the cover 2 is screwed on the connecting piece 7 fixed on the adjustment circuit board 9 . Therefore, the signal received by the antenna unit 1 screwed on the component connecting fitting 2-7 can be introduced into the adjustment circuit board 9 through the component connecting fitting 2-7 and the connecting screw 4. Then, in the adjustment circuit board 9 and the amplifier circuit board 8 (not shown), each reception signal after frequency division and amplification is introduced into the vehicle body interior as the mounted object through the telephone cable 20 and the radio cable 21 .

In addition, the telephone cable 20 and the radio cable 21 are drawn out through the fixing screw portion 3-9 formed in a cylindrical shape.

The adjustment circuit board 9 and the amplifier circuit board 8 are fixed upright on the circuit board bracket 12 . At this time, the grounding parts of the two circuit boards 8, 9 are electrically connected to the circuit board bracket 12, and then can be grounded on the mounted body through the base.

In addition, the GPS antenna 10 is housed and held in the space formed by the cover 2 and the base 3 . The GPS antenna 10 is provided in a rectangular shape, and is housed in a rectangular housing portion 3 - 10 formed of a protrusion 3 - 1 erected on the base 3 surrounding the GPS antenna 10 . The upper end surface of the GPS antenna 10 is pressed by pressing protrusions 2-2 formed at four places on the inner surface of the cover 2, whereby the GPS antenna 10 can be held in the storage portion 3-10.

In addition, on the outer periphery of the pressing protrusion 2-2 formed on the cover 2, a protrusion 2-1 having approximately the same shape and capable of accommodating the GPS antenna 10 is formed facing the protrusion 3-1 formed on the base 3. .

In addition, a wave spring 11 is placed on the lower end of the GPS antenna 10, so as to ensure that the GPS antenna 10 is kept in the receiving portion 3-10. A circuit board assembled with a circuit for processing GPS signals is disposed below the GPS antenna 10, and since the circuit board is disposed in the conductive housing portion 3-10, it can be shielded by the housing portion 3-10. Therefore, the GPS antenna 10 can operate stably, and the GPS signal can be introduced into the body to be installed through the GPS cable 19 .

At this time, a groove 3-8 for leading out the GPS cable 19 is formed on the protrusion 3-1, and the GPS cable 19 embedded in the groove 3-8 is pulled out from the protrusion 2-8 formed on the cover 2. 1 further protrude the formed cable pressing projection 2-8 to press and hold.

In addition, a groove 2-6 is formed on the entire peripheral surface of the lower end portion of the cover 2, and a waterproof gasket 6 is embedded in the groove 2-6, and the protruding part 3-6 embedded in the groove 2-6 is formed on the entire peripheral surface. is formed on the base 3. Therefore, when the cover 2 is fitted on the base 3 as shown in the figure, the protrusions 3-6 are crimped on the waterproof gasket 6 to form a waterproof fit.

The base 3 is made of metal or a conductive coating is formed on the entire surface, which is made conductive; a soft gasket 15 is arranged under the base 3, and the base 3 is placed on the installed body; the fixing screw part 3- 9 is inserted into a rectangular mounting hole formed on the mounted body. The base 3 can be fixed to the mounted body by tightening the nut 16 on the fixing screw portion 3-9 protruding to the rear surface of the mounted body. At this time, the base 3 is connected to the mounted body and grounded.

Furthermore, as shown in FIG. 3( b ), the GPS antenna 10 is arranged substantially parallel to the base 3 , and the amplifier circuit board 8 and the adjustment circuit board 9 are arranged upright. Therefore, the actual grounding area increases, improving the grounding effect of the GPS antenna 10 . Moreover, even if the GPS satellite is at a low elevation angle, the influence of the circuit board on the GPS antenna 10 can be prevented as much as possible.

In addition, the antenna unit 1 is installed with an inclination of about 20° to 35° relative to the vertical line, so even if the GPS satellite is at a low elevation angle, the influence of the antenna unit 1 on the GPS antenna 10 can be prevented as much as possible.

Next, the configuration of the circuit board 12 is shown in FIG. 5 . The circuit board bracket 12 is formed into the shape shown in FIG. 5 by processing a metal plate, and a set of circuit board fixing parts 12-1 and 12-2 are respectively formed on two long sides. The circuit board fixing part 12 - 1 is a fixing part for fixing the adjustment circuit board 9 , and the circuit board fixing part 12 - 2 is a fixing part for fixing the amplifier circuit board 8 . The circuit board fixing parts 12 - 1 , 12 - 2 are formed into a fork shape, and the interval of the fork shape is set to be substantially equal to the thickness of the circuit boards 8 , 9 . Then, by fixing the slits 8-2, 9-2 formed on the circuit boards 8, 9 respectively on the circuit board fixing parts 12-1, 12-2 as shown in the figure, the positions of the circuit boards 8, 9 can be determined. Location.

And, after the circuit boards 8, 9 are placed on the circuit board fixing parts 12-1, 12-2, by soldering the grounding parts 8-1, 9-1 of the circuit boards 8, 9 to the circuit board fixing part 12- 1, 12-2, the circuit boards 8, 9 are fixed on the circuit board bracket 12. At this time, the ground portions 8 - 1 , 9 - 1 of the circuit boards 8 , 9 are electrically connected to the circuit board bracket 12 .

In addition, one set of cut and folded pieces 12 - 3 is made as a cut and folded piece for cable pressing of the GPS cable 8 . Furthermore, another set of cut and folded pieces 12-4 is a cut and folded piece for soldering and fixing the grounding bracket 17 described later, and the through hole 12-5 is a through hole through which various cables are passed. .

In addition, the matching holes 12-7 formed in three places are matching holes on the matching protrusion 3-11 on the above-mentioned base 3 as shown in Figure 4 (b), and the circuit board is determined by matching. The position of the bracket 12 on the base 3 and the matching protrusion 3-11 are fixed by riveting.

Next, Figure 6 shows the structure of the grounding bracket 17, Figure 6(a) is a side view of the grounding bracket 17, Figure 6(b) is a front view of the grounding bracket 17, and Figure 6(c) is Top view of grounding bracket 17.

As shown in these figures, a clamping portion 17-3 that surrounds a slightly thicker radio cable 21 and a clamping portion 17-3 that surrounds a slightly thinner telephone cable 20 are formed on the grounding bracket 17. 4. The cables 20, 21 are respectively held in these holding portions 17-3, 17-4, and soldered from the window portion 17-2 formed on the side. Thereby, the ground/bracket 17 can be electrically connected to the ground portions of the cables 20 and 21 .

In addition, a protruding part 17-1 protrudes from the side of the grounding bracket 17, and the protruding part 17-1 is soldered to a set of cut and folded pieces of the circuit board bracket 12 as shown in FIG. Solder part 12-6 between 12-4.

As a result, the ground bracket 17 is fixed to the board bracket 12 and is electrically connected at the same time. Thus, the grounded portions of the cables 20 , 21 can be grounded through the circuit board bracket 12 . In addition, the cables 20, 21 can be drawn out vertically.

Furthermore, in the multi-frequency antenna of the present invention, the antenna unit 1 is a 3-frequency shared antenna, but the present invention is not limited thereto, and may be a 2-frequency shared antenna of the AM band and the FM band. Industrial Utilization Possibility

Since the present invention is constituted as above, an antenna storage portion is not required under the multi-frequency antenna, and when mounted on a vehicle body, it can be mounted on a high place such as a roof where there is no storage space. Therefore, it is possible to prevent GPS radio waves received by the GPS antenna from being shielded by an attached body such as a vehicle body.

Also, since the circuit board is configured to be orthogonal to the GPS antenna, the grounding effect of the GPS antenna can be improved. Furthermore, even though the GPS radio waves are transmitted at a low elevation angle, since the circuit board is installed upright and the antenna unit is arranged at an angle, the influence on the GPS antenna can be prevented as much as possible.

Also, since the circuit board for processing the signal received by the GPS antenna is shielded, the GPS antenna can be stably operated.

Claims (4)

1, a kind of multiple frequency antenna is characterized in that:

Possess whiplike antenna element, it can receive the signal of AM broadcast band and FM broadcast band at least;

And antenna case, it can install described antenna element, and the circuit board that has adjusting device, frequency divider and amplifying device is at least taken in by portion within it simultaneously, and gps antenna.

This antenna case is made up of the base of conductivity and the lid that is inlaid on this base; The foregoing circuit plate erectly is fixed on the above-mentioned base; On above-mentioned base, form the gps antenna containing section that is useful on the installation gps antenna orthogonally simultaneously with the foregoing circuit plate;

2, multiple frequency antenna as claimed in claim 1 is characterized in that: it is fixed on the top of car body.

3, multiple frequency antenna as claimed in claim 1 is characterized in that: be formed on the above-mentioned gps antenna containing section on the base of above-mentioned conductivity, formed by the projection of the periphery that surrounds above-mentioned gps antenna; By the circuit board of above-mentioned gps antenna containing section shield configuration at the above-mentioned gps antenna back side.

4, multiple frequency antenna as claimed in claim 1 is characterized in that: above-mentioned antenna element, and about 20 ° to 35 ° from upright inclined position, and be installed on the above-mentioned antenna case.

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