JP2001332919A - Gps sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a GPS sensor, with which reception sensitivity will not deteriorate even if a power feeding part and a preamplifier part are approaching on a reception circuit board. SOLUTION: On a reception circuit board 2, mounted with a power feeding part 20 to feed power to a GPS antenna and a preamplifier part 21 for GPS antenna output, a ground 5 is provided for isolating the power feed part 20 and the preamplifier part 21.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a GPS sensor, and more particularly to a small GPS sensor having a GPS antenna and a receiving circuit integrated.

[0002]

2. Description of the Related Art There is a small GPS sensor 1 in which a GPS antenna and a receiving circuit are integrated. FIG. 2 shows an example. A receiving circuit board 2 covered with a shield cover 3 is arranged in a case 10 having an elongated rectangular shape, and a GPS antenna 4 is arranged on a shield cover 13. In the figure, reference numeral 40 denotes a receiving circuit board 2 projecting from the GPS antenna 4.
The power supply pin 11 is a connector for connection to the outside.

In such a GPS sensor 1, a power supply unit 2 to which the power supply pin 40 is connected is provided on the receiving circuit board 2.
0, the preamplifier 21 and the R shown in FIG.
The F section 22 and the arithmetic processing section 23 are arranged and mounted.

[0004]

Here, if the receiving circuit board 2 is elongated, as shown in FIG.
The power supply unit 20 and the preamplifier unit 21 are arranged close to each other. However, when the leakage of the signal amplified by the preamplifier unit 21 is input to the power supply unit 20 again, oscillation may occur. However, even when the signal does not occur, the harmonics of the vibrating oscillator of the RF unit 22 and the arithmetic processing unit 23 and the high-frequency components used for demodulation are input to the power supply unit 20 as leaks, thereby deteriorating the receiving sensitivity. This tendency is caused by the power supply pin 40
Is large on the exposed side.

The present invention has been made in view of such a point, and an object of the present invention is that even if the power supply unit and the preamplifier unit are close to each other on the receiving circuit board, this is a cause of deterioration of the receiving sensitivity. An object of the present invention is to provide a GPS sensor that does not cause the above problem.

[0006]

SUMMARY OF THE INVENTION Accordingly, the present invention provides a GP
It is characterized in that a ground for isolating the power supply unit and the preamplifier unit is provided on the receiving circuit board on which the power supply unit for the S antenna and the GPS antenna output preamplifier unit are mounted.

The ground is preferably formed by a copper foil pattern on the receiving circuit board, but is not limited to this.

In the case where the power supply section of the receiving circuit board and the GPS antenna are connected by a power supply pin on one side of the receiving circuit board, it is preferable to arrange the output section of the preamplifier section on the other side of the receiving circuit board.

A line pattern of the output section of the preamplifier section may be provided on an inner layer of the receiving circuit board, and a copper foil ground plane may be provided above and below the line pattern.

[0010] Further, when the power supply section of the receiving circuit board and the GPS antenna are connected by a power supply pin on one side of the receiving circuit board, and the output section of the preamplifier section is also located on one side of the receiving circuit board, The output section of the section and the ground may be covered with a common metal member.

The power supply pin for connecting the power supply section of the receiving circuit board and the GPS antenna may be covered with a metal member having a common ground. In this case, the metal member covering the power supply pin may include a shield covering the reception circuit board. A cover may be used.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to an example of an embodiment. The basic configuration of a GPS sensor 1 is the same as that described above with reference to FIGS. A receiving circuit board 2 covered with a shield cover 3 is arranged in a case 10 having a shape, and a GPS antenna 4 is arranged on a shield cover 13. Then, in addition to the power supply unit 20 to which the power supply pin 40 is connected, a preamplifier unit 21, an RF unit 22, and an arithmetic processing unit 24 are arranged and mounted on the receiving circuit board 2.

Here, in the present invention, as shown in FIG. 1, a copper foil pattern of the receiving circuit board 2 is provided between the power supply section 20 to which the GPS antenna 4 is connected via the power supply pin 40 and the preamplifier section 21. Ground 5 composed of
And the two are separated by a ground 5. For this reason, re-input of a signal to the power supply unit 20 can be prevented. The ground 5 for isolation may be formed of a metal plate common to the ground instead of the copper foil pattern of the receiving circuit board 5.

At least the output section 25 of the preamplifier section 21
As shown in FIG. 4, it is also effective to arrange on the back surface of the receiving circuit board 2 opposite to the surface where the power supply pins 40 connected to the power supply unit 20 are located. In this case, a part of the ground 5 is also arranged on the back side. In the figure, reference numeral 27 denotes a through hole for front and back electrical connection.

FIG. 5 shows another example. Here, the line pattern of the output section 25 of the preamplifier section 21 is arranged in the inner layer of the receiving circuit board 2, and the grounds 5 and 5 made of a copper foil pattern are arranged on the upper and lower outer layers of the line pattern. Sandwich the line pattern. Of course, the copper foil grounds 5 and 5 may be formed as an inner layer pattern of the receiving circuit board 2.

FIGS. 6 and 7 show still another example. Here, the isolation is performed by covering the preamplifier section 21 (at least the output section 25) with the ground 5 made of a metal plate on one side of the receiving circuit board 2 where the power supply pins 40 are exposed.

Conversely, as shown in FIGS. 9 and 10, the power supply pin 40 side may be covered with a ground 5 made of a cylindrical metal plate. In this case, the ground 5 is preferably integrated with the shield cover 3. Can be used. The ground 5 formed of a cylindrical metal tube independent of the shield cover 3 may be shared by soldering.

[0018]

As described above, in the present invention, the GPS
Since the receiving circuit board on which the feeding section for the antenna and the preamplifier section for outputting the GPS antenna are mounted is provided with a ground for isolating the feeding section and the preamplifier section, a signal leaking from the preamplifier section is supplied to the feeding section. Is rarely re-input, and therefore does not cause oscillation or decrease in reception sensitivity. In addition, there is no restriction on the arrangement of the preamplifier unit and the power supply unit close to each other. In addition, the degree of freedom in board design is increased, which is advantageous for miniaturization of the GPS sensor.

[Brief description of the drawings]

FIG. 1 is a plan view of a receiving circuit board according to an example of an embodiment of the present invention.

FIG. 2 shows an overall configuration of the GPS sensor according to the first embodiment;
(a) is a transverse sectional view, and (b) is a longitudinal sectional view.

FIG. 3 is a block circuit diagram of the same.

FIG. 4 is a plan view of a receiving circuit board in another example.

FIG. 5 is a plan view of a receiving circuit board in still another example.

FIG. 6 is a plan view of a receiving circuit board in another example.

FIG. 7 is a transverse sectional view of the same.

FIG. 8 is a plan view of a receiving circuit board in still another example.

FIG. 9 is a cross-sectional view of the same.

FIG. 10 is a plan view of a conventional receiving circuit board.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 GPS sensor 2 Receiving circuit board 5 Ground 20 Power supply part 21 Preamplifier part

Claims (7)

[Claims] 1. A GPS, wherein a ground for isolating the power supply unit and the preamplifier unit is provided on a receiving circuit board on which a power supply unit for the GPS antenna and a preamplifier unit for outputting the GPS antenna are mounted. Sensor. 2. The GP according to claim 1, wherein the ground is formed by a copper foil pattern on the receiving circuit board.
S sensor. 3. The power supply section of the receiving circuit board and the GPS antenna are connected on one side of the receiving circuit board, and the output section of the preamplifier section is provided on the other side of the receiving circuit board. The GPS according to claim 1 or 2,
Sensor. 4. The GPS according to claim 1, wherein a line pattern of an output section of the preamplifier section is provided on an inner layer of the receiving circuit board, and a copper foil ground plane is provided above and below the line pattern. Sensor. 5. A power supply section of a receiving circuit board and a GPS antenna are connected by a power supply pin on one side of the receiving circuit board, and an output section of a preamplifier located on one side of the receiving circuit board shares a ground with a ground. The GPS sensor according to claim 1, wherein the GPS sensor is covered with a metal member. 6. The GPS sensor according to claim 1, wherein a power supply pin connecting the power supply section of the receiving circuit board and the GPS antenna is covered with a metal member having a common ground. 7. A metal cover for covering a power supply pin is a shield cover for covering a receiving circuit board.
The GPS sensor as described.