JP2001297918A - Coil antenna and portable communication apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve a problem in which a coil antenna is hard to be decreased in required space, not easily fabricated, and hard to be lessened in cost. SOLUTION: A first coil is formed of a wiring pattern 15 formed on the surface of an insulating layer 2-2. A second coil is formed of viaholes 11 and a wiring pattern 12 vertical to the first coil. Furthermore, a third coil is formed of viaholes 13 and a wiring pattern 14 vertical to both the first and second coil.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coil antenna and a portable communication device having the same.

[0002]

2. Description of the Related Art FIG. 5 is a diagram showing an example of a vehicle key system, FIG. 6 is a circuit diagram showing a configuration of a portable communication device in the vehicle key system, and FIG. 7 is provided in the portable communication device. FIG. 10 is a diagram illustrating a conventional coil antenna.

In FIG. 5, 41 is carried by the user,
A coil antenna detects a change in the magnetic field of a predetermined low frequency (134 kHz in this case) from the vehicle 42, and outputs a command such as unlocking of a door lock as a radio wave of a predetermined high frequency (315 MHz in this case). It is a portable communication device that transmits.

In the portable communication device 41 shown in FIG.
Is a coil for detecting a magnetic field change in the X axis direction, 52 is a coil for detecting a magnetic field change in the Y axis direction, and 53 is a coil for detecting a magnetic field change in the Y axis direction.
This is a coil for detecting a magnetic field change in the axial direction. 54 is a capacitor that is connected in parallel with the coil 51 and forms a resonance circuit with the coil 51; 55 is a capacitor that is connected in parallel with the coil 52 and forms a resonance circuit with the coil 52; Connected to
This is a capacitor that forms a resonance circuit together with the coil 53.

In a conventional coil antenna, for example, as shown in FIG. 7, a coil for any one of the X, Y, and Z axes is formed as a coil element 110 on a substrate 101, and the remaining two axes are formed. As a coil for the direction of 2
The two coil elements 112 and 114 are connected to the substrate 101.

[0008] 57 demodulates a voltage signal corresponding to a predetermined low-frequency magnetic field change detected by the coils 51 to 53 and the capacitors 54 to 56, and supplies a signal from the vehicle 42 to the microcomputer and the peripheral circuit 58. L
F (Low Frequency) demodulation circuit (communication circuit)
Reference numeral 8 denotes a microcomputer and peripheral circuits that execute a process according to a signal from the vehicle 42 and supply a command to be transmitted to the vehicle 42 to the UHF circuit 59,
Reference numeral 59 denotes a UHF (Ultra High Frequency) circuit which modulates a command from the microcomputer and the peripheral circuit 58 and radiates it as a high-frequency radio wave through an antenna.
Reference numeral 60 denotes a battery that supplies power to each unit.

In FIG. 5, reference numeral 81 denotes a body ECU (Electric Control Unit) which is provided on a vehicle 42, drives a mirror antenna 82, and executes processing such as unlocking of a door lock in response to a command from the portable communication device 41. ). In the body ECU 81, reference numeral 91 denotes the portable communication device 4.
1 is a keyless tuner that senses a predetermined high-frequency radio wave from the antenna 1 and demodulates its electric signal and supplies a command from the portable communication device 41 to the microcomputer 92. Reference numeral 92 denotes a command from the portable communication device 41. Reference numeral 93 denotes an LF modulation circuit that modulates a predetermined low-frequency carrier with a signal from the microcomputer 92 and supplies a modulation signal to a current boost circuit 94; This is a current boost circuit that current-amplifies the signal from the modulation circuit 93 and drives the mirror antenna 82.

[0008] 82 is built in the door mirror of the vehicle 42,
A mirror antenna 83 for generating a magnetic field change of a predetermined low frequency (134 kilohertz in this case) is provided on the vehicle 42, drives a key cylinder antenna 84 for the immobilizer, and performs a predetermined operation by the transponder 71 for the immobilizer of the vehicle key 43. Is an immobilizer that permits the engine to start only when the signal is detected. Reference numeral 84 denotes an immobilizer key cylinder antenna provided on the ignition operation key cylinder.

Reference numeral 43 denotes a transponder 71 for an immobilizer.
Is a mechanical vehicle key with a built-in key.

Next, the operation will be described. Portable communication device 4
A conventional coil antenna provided as the coil elements 112 and 114 and the coil element 110 on one substrate 101 detects a magnetic field change in any direction in a three-dimensional space.

The change in the magnetic field caused by the mirror antenna 82 of the vehicle 42 is detected by the coil antenna of the portable communication device 41, and a corresponding voltage signal is supplied to the LF demodulation circuit 57. The LF demodulation circuit 57 demodulates the voltage signal and supplies the original signal to the microcomputer and the peripheral circuit 58.

Microcomputer and peripheral circuit 58
Performs a predetermined process according to the signal or user operation. The microcomputer and the peripheral circuit 58
Supplies a command to be transmitted to the vehicle 42 to the UHF circuit 59, and the UHF circuit 59 modulates the carrier with a command from the microcomputer and the peripheral circuit 58 and radiates it as a high-frequency radio wave via the antenna.

The electric wave is detected by the body ECU 81 of the vehicle 42, and the vehicle 42 executes a process and an operation according to the received signal.

[0014]

Since the conventional coil antenna is constructed as described above, it is difficult to reduce the space required for the coil antenna, and it is difficult to manufacture the coil antenna, thereby reducing the cost. There was a problem that it was difficult.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems. Since a coil is formed in a wiring layer between any two insulating layers of a multilayer substrate, a necessary space is reduced. It is an object of the present invention to provide a coil antenna and a portable communication device that can be formed easily.

Further, according to the present invention, a first coil is formed along a surface of a substrate, and the first coil is formed through a hole provided in the substrate.
A second coil is formed perpendicular to the first coil, and a third coil is formed perpendicularly to the first coil and also perpendicular to the second coil through the hole. To reduce the required space,
An object is to provide a coil antenna and a portable communication device that can be easily formed.

Further, according to the present invention, the first bobbin is provided on the same bobbin.
Coil, the second coil and the third coil are wound so as to be orthogonal to each other to reduce the number of parts,
It is an object of the present invention to provide a coil antenna and a portable communication device that can reduce a required space and can be easily formed.

[0018]

A coil antenna according to the present invention includes a multilayer substrate and a coil formed on a wiring layer between any two insulating layers of the multilayer substrate.

A portable communication device according to the present invention communicates with a coil antenna having a multi-layer substrate and a coil formed on a wiring layer between any two insulating layers of the multi-layer substrate via the coil antenna. And a communication circuit.

A coil antenna according to the present invention includes a substrate, a first coil formed along a surface of the substrate, a plurality of holes provided in the substrate, and a first coil formed through the hole.
And a third coil formed perpendicularly to the first coil and perpendicular to the second coil through the hole. It is provided.

In the coil antenna according to the present invention, a first coil, a second coil, a third coil, and a hole are formed in any one of the insulating layers of the multilayer substrate.

In the coil antenna according to the present invention, the first coil comprises a wiring pattern, the second coil comprises a plurality of via holes and a wiring pattern, and the third coil comprises a plurality of via holes and a wiring pattern. It is made to consist of.

According to the portable communication device of the present invention, a substrate, a first coil formed along a surface of the substrate, a plurality of holes provided in the substrate, and a first coil formed through the holes. A coil antenna having a second coil formed perpendicular to the first coil, and a third coil formed perpendicular to the first coil and perpendicular to the second coil through the hole. And a communication circuit for communicating via the coil antenna.

A coil antenna according to the present invention comprises a bobbin, a first coil wound on the bobbin, a second coil wound on the bobbin orthogonal to the first coil, and a first coil. And a third coil wound on a bobbin orthogonally to the second coil.

A portable communication device according to the present invention comprises: a bobbin;
A first coil wound on the bobbin, a second coil wound on the bobbin orthogonal to the first coil, and a coil wound on the bobbin orthogonal to the first coil and the second coil And a communication circuit for communicating via the coil antenna.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below. Embodiment 1 FIG. FIG. 1 is a perspective view showing an example of a multilayer substrate on which a coil antenna according to Embodiment 1 of the present invention is formed. FIG. 2 is a sectional view showing the surface of the insulating layer 2-2 on which the coil antenna according to the first embodiment is formed.
FIG. 3 is a cross-sectional view showing the back surface of the insulating layer 2-2 on which the coil antenna according to the first embodiment is formed.

In FIG. 1, reference numeral 1 denotes a four-layer board (substrate, multilayer board) which is built in the portable communication device 41 and on which various circuits are provided, and 2-1 2-2 and 2-3 denote insulating layers. , 3-1, 3-2, 3-3 and 3-4 are wiring layers.

The surface of the insulating layer 2-2 shown in FIG.
On the back surface of the insulating layer 2-2 shown in FIG.
2, a part of the coil 21 for the X-axis direction filled with a conductor and filled with a conductor.
Reference numeral 12 denotes a wiring pattern formed on the front surface and the back surface of the insulating layer 2-2 and constituting a part of the coil 21 for the X-axis direction. That is, via hole 11
The wiring pattern 12 forms a spiral coil 21 (second coil).

Reference numeral 13 denotes a via hole that penetrates through the insulating layer 2-2 and is filled with a conductor, and constitutes a part of the coil 22 for the Y-axis direction. Coil 22 for Y-axis direction formed on front and back surfaces
Is a wiring pattern constituting a part of the wiring pattern. That is, the coil 2 is formed by the via hole 13 and the wiring pattern 14.
A spiral coil (third coil) 22 perpendicular to 1 is formed.

Numeral 15 is formed on the surface of the insulating layer 2-2.
This is a wiring pattern constituting a coil (first coil) for the Z-axis direction perpendicular to the coils 21 and 22. That is, the coil for the Z-axis direction is formed in the wiring layer 3-2 between the two insulating layers 2-1 and 2-2 of the four-layer substrate 1.

The four-layer board 1 is provided with other circuits (excluding the coils 51, 52, and 53) shown in FIG. 6, but the arrangement and wiring patterns of the circuits are not particularly relevant to the present invention. Therefore, the description is omitted.

Next, the operation will be described. Portable communication device 4
A three-dimensional coil antenna formed of wiring patterns 12, 14, 15 and via holes 11, 13 on the four-layer substrate 1 detects a magnetic field change in any direction in a three-dimensional space.

A change in the magnetic field caused by the mirror antenna 82 of the vehicle 42 is detected by the coil antenna of the portable communication device 41, and a voltage signal corresponding thereto is supplied to the LF demodulation circuit 57. The LF demodulation circuit 57 demodulates the voltage signal,
The original signal is supplied to the microcomputer and the peripheral circuit 58.

Microcomputer and peripheral circuit 58
Performs a predetermined process according to the signal or user operation. The microcomputer and the peripheral circuit 58
Supplies a command to be transmitted to the vehicle 42 to the UHF circuit 59, and the UHF circuit 59 modulates the carrier with a command from the microcomputer and the peripheral circuit 58 and radiates it as a high-frequency radio wave via the antenna.

The electric wave is detected by the body ECU 81 of the vehicle 42, and the vehicle 42 executes processing and operation according to the received signal.

In the first embodiment, a four-layer multi-layer substrate is used as the substrate, but a multi-layer substrate having a different number of layers or a single-layer substrate may be used. Also,
The arrangement and the number of turns of each coil shown in FIGS. 2 and 3 are merely examples, and other arrangements and the number of turns may be used.

As described above, according to the first embodiment, the coil formed on the wiring layer 3-2 between the two insulating layers 2-1 and 2-2 of the four-layer substrate 1 is provided. Therefore, the end surfaces (wiring layers 3-1 and 3-4) of the four-layer board 1 can be used for other circuits, and the circuit arrangement can be efficiently performed. Can be easily formed.

According to the first embodiment, the first coil (wiring pattern 15) formed along the surface of insulating layer 2-2 and the first coil via via hole 11 Since the coil 21 formed vertically and vertically and the coil 22 formed perpendicularly to the first coil and the coil 21 via the via hole 13 are used as the coil antenna of the portable communication device 41, the coil antenna necessary for the coil antenna is provided. The space can be reduced, the size of the portable communication device 41 can be reduced, and the coil antenna, and hence the portable communication device 41 can be reduced.
Can be easily created.

The coil antenna is connected to the portable communication device 4.
Since it is used in No. 1, the user can operate the mobile communication device 41 without being conscious of the orientation of the mobile communication device 41, and the effect of improving convenience can be obtained.

Embodiment 2 FIG. 4 is a front view and a side view showing a coil antenna according to a second embodiment of the present invention. In FIG. 4, 31 is a bobbin, 32 is a coil (first coil) wound on the bobbin 31, and 3
Reference numeral 3 denotes a coil (second coil) wound on the bobbin 31 orthogonal to the coil 32, and reference numeral 34 denotes a coil (third coil) wound on the bobbin 31 orthogonal to the coil 32 and the coil 33. It is. That is, the coil 33 is wound vertically outside the coil 32, the diameter of the coil 32 and the diameter of the coil 33 become common, and the coil 34 is wound around the diameter.

The coil antenna is provided in the portable communication device 41 as the coils 51, 52, and 53 shown in FIG. 6, but since the circuit arrangement and the wiring pattern are not particularly related to the present invention, the description thereof will be omitted. Is omitted.

Next, the operation will be described. Portable communication device 4
1, the three-dimensional coil antenna shown in FIG.
A magnetic field change in any direction of the dimensional space is detected. Other operations are the same as those according to the first embodiment, and a description thereof will be omitted.

As described above, according to the second embodiment, the coil 32, the coil 33 and the coil 34 are wound around the same bobbin 31 so as to be orthogonal to each other. The effect that the space required for the coil antenna can be reduced, the portable communication device 41 can be downsized, and the coil antenna, and consequently, the portable communication device 41 can be easily created can be obtained.

The coil antenna is connected to the portable communication device 4.
Since it is used in No. 1, the user can operate the mobile communication device 41 without being conscious of the orientation of the mobile communication device 41, and the effect of improving convenience can be obtained.

In the first and second embodiments,
Although coil antennas are used in portable communication devices, they can be used in other devices.

[0046]

As described above, according to the present invention, since the coil is formed in the wiring layer between any two insulating layers of the multilayer substrate, the end face of the multilayer substrate is used for another circuit. The circuit arrangement can be performed efficiently, and the coil antenna, and thus the portable communication device, can be easily created.

According to the present invention, the first coil is formed along the surface of the substrate, and the first coil is formed through the hole provided in the substrate.
A second coil is formed perpendicular to the first coil, and a third coil is formed perpendicularly to the first coil and also perpendicular to the second coil through the hole. Therefore, the space required for the coil antenna can be reduced, the size of the portable communication device can be reduced, and the coil antenna and, consequently, the portable communication device can be easily manufactured.

According to the present invention, the first coil, the second coil, and the third coil are wound around the same bobbin so as to be orthogonal to each other. The required space can be reduced, and the portable communication device can be downsized.
There is an effect that a coil antenna, and eventually a portable communication device, can be easily created.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of a multilayer substrate on which a coil antenna according to a first embodiment of the present invention is formed.

FIG. 2 is a cross-sectional view showing a surface of the insulating layer on which the coil antenna according to the first embodiment is formed.

FIG. 3 is a cross-sectional view showing the back surface of the insulating layer on which the coil antenna according to the first embodiment is formed.

FIG. 4 is a front view and a side view showing a coil antenna according to a second embodiment of the present invention.

FIG. 5 is a diagram showing an example of a vehicle key system.

FIG. 6 is a circuit diagram showing a configuration of a portable communication device in the vehicle key system.

FIG. 7 is a diagram showing a conventional coil antenna provided in a portable communication device.

[Explanation of symbols]

14-layer board (substrate, multilayer board), 2-1 to 2-3 insulating layer, 3-1 to 3-4 wiring layer, 11, 13 via hole (hole), 12, 14, 15 wiring pattern, 21 coil (Second coil), 22 coils (third coil), 31 bobbins, 32 coils (first coil),
33 coils (second coil), 34 coils (third coil), 57 LF demodulation circuit (communication circuit).

Claims (8)

[Claims] 1. A coil antenna comprising: a multilayer substrate; and a coil formed in a wiring layer between any two insulating layers of the multilayer substrate. 2. A multi-layer substrate and one of the multi-layer substrates
A portable communication device, comprising: a coil antenna having a coil formed in a wiring layer between two insulating layers; and a communication circuit communicating via the coil antenna. 3. A substrate, a first coil formed along the surface of the substrate, a plurality of holes provided in the substrate, and perpendicular to the first coil through the holes. A coil antenna, comprising: a formed second coil; and a third coil formed perpendicular to the first coil and perpendicular to the second coil through the hole. 4. The multi-layer substrate, wherein the first coil, the second coil, the third coil, and the hole are formed in any one of the insulating layers of the multi-layer substrate. Item 3. The coil antenna according to Item 3. 5. The hole is a via hole, the first coil is formed of a wiring pattern, the second coil is formed of a plurality of the via holes and a wiring pattern, and the third coil is formed of a plurality of wiring patterns. 5. The coil antenna according to claim 3, wherein said coil antenna is constituted by said via hole and a wiring pattern. 6. A substrate, a first coil formed along a surface of the substrate, a plurality of holes provided in the substrate, and a plurality of holes provided in the substrate, the holes being perpendicular to the first coil through the holes. A coil antenna having a second coil formed, and a third coil formed perpendicular to the first coil through the hole and perpendicular to the second coil; A portable communication device comprising: a communication circuit that performs communication via the coil antenna. 7. A bobbin, a first coil wound on the bobbin, a second coil wound on the bobbin orthogonally to the first coil, the first coil and the first coil And a third coil wound around the bobbin orthogonally to the second coil. 8. A bobbin and a first bobbin wound on the bobbin.
A second coil wound on the bobbin orthogonal to the first coil, and a third coil wound on the bobbin orthogonal to the first coil and the second coil.
A portable communication device comprising: a coil antenna having the following coils: and a communication circuit that communicates via the coil antenna.