JPH0922449A - Transmission-reception system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transmission-reception system which can reduce the power consumption of an external receiver. SOLUTION: When a start switch 4a is turned on by an operator, a microcomputer 6 of a holder 1 reads a start signal code out of an IC card 2a and transmits a start signal (1) via a transmitting device 7 and an antenna coil 8. A microcomputer 11 of the card 2a receives the signal (1) via an antenna coil 14 and a receiving device 12 and sends an ID code to a communication device 16 as an answer signal (2). The device 16 receives the signal (2) via an antenna coil 21 and a receiving device 19 and collates the signal (2) with an ID code that is previously set. When the signal (2) is coincident with the ID code, the device 16 sends a control signal to a processor 20. Thus the processor 20 cancels a door lock state.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission / reception system using an IC card for transmitting / receiving data by airborne signals.

[0002]

Such a transmission / reception system is also used, for example, in an electronic key system for a vehicle. Thus, the conventional electronic key system for vehicles is
An IC coil as an electronic key is provided with an antenna coil,
A card reader as an external receiver on the vehicle side is provided with an antenna coil that is electromagnetically coupled to the antenna coil of the IC card, and an inquiry signal is transmitted from the antenna coil of the card reader as an electromagnetic induction signal which is an airborne propagation signal. Is received by the antenna coil of the card reader, the card reader transmits an ID code signal unique to the vehicle as a response signal from the antenna coil. The card reader reads the ID code transmitted from the IC card, The ID code stored in advance on the vehicle side is compared with each other, and if they match, the door lock or unlock or engine start is performed.

However, such a transmission / reception system has the following problems. First, since it is not known when the IC card is sent and received, the card reader must always send the inquiry signal. In particular, when an electromagnetic induction signal is used as the air propagation signal, it is difficult to increase the receiving sensitivity of the antenna coil provided in the IC card, and therefore the card reader must transmit the inquiry signal with high power. Further, in order to expand the receivable area of the activation signal in order to improve the convenience, the card reader needs to transmit the interrogation signal with larger power.

The present invention solves the above problems, and an object thereof is to provide a transmitting / receiving system capable of reducing the power consumption of an external receiver.

[0005]

In order to achieve the above object, a transmitting / receiving system according to claim 1 comprises a starting switch and a transmitting means for transmitting the starting signal as an airborne signal in response to the operation of the starting switch. A holder and a transmitter / receiver attached to the holder and having a transmitter / receiver means, and when the transmitter / receiver means receives a start signal from the transmitter means of the holder, the transmitter / receiver means transmits a response signal as an airborne signal
It is characterized by including a C card and an external receiver that executes a predetermined process when a response signal from the IC card is received.

In this case, the holder is configured to selectively transmit a start signal corresponding to a plurality of different types of IC cards, and each IC card receives a start signal assigned to itself. It may be configured to transmit a response signal (Claim 2).

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a vehicle electronic key system will be described below with reference to the drawings. FIG. 2 shows the appearance of the holder 1 and the three IC cards 2a, 2b, and 2c attached to the holder 1. In FIG. 2, the body case 3 of the holder 1 is
It has storage parts 3a, 3b and 3c which are formed in a rectangular container shape and one end surface of which is opened in a slit shape so as to store the three IC cards 2a, 2b and 2c therein. On the upper surface of the main body case 3, the IC cards 2a, 2b and 2
Starting switches 4a, 4b and 4 corresponding to each of c
c is provided. The IC cards 2a, 2b and 2
The letters c are configured as, for example, a vehicle electronic key, a commuter pass card, and an entry certificate card, respectively.

In FIG. 1 showing the electrical structure, a holder 1
Has a battery 5 therein, and the battery 5 is configured to supply power to a microcomputer (hereinafter referred to as a microcomputer) 6 and a transmitter 7. The start-up switches 4a to 4c are, for example, push switches that operate momentarily, and their output terminals are connected to different trigger signal input terminals of the microcomputer 6, respectively. When the start switches 4a, 4b and 4c are turned on by being pressed by the operator, the high level start trigger signals A1, A2 and A3 are output only during the on operation. ing.

The microcomputer 6 has a ROM (not shown) for storing a control program and an EEPROM for storing the ID codes of the IC cards 2a to 2c therein. The data output terminal of the microcomputer 6 is connected to the data input terminal of the transmitter 7. Then, the transmitter 7
Has its output terminal connected to the antenna coil 8 and outputs the data B supplied from the microcomputer 6 to the antenna coil 8 as a modulated signal. The transmitter 7 and the antenna coil 8 form a transmitter 9.

Regarding the structure of the IC card, the IC card 2a as an electronic key will be described below. The IC card 2a has a battery 10 inside, and the battery 10
Is a microcomputer 11, a receiver 12, and a transmitter 13.
Is configured to be supplied with power.

The microcomputer 11 has a ROM (not shown) for storing a control program, a RAM for data processing,
Further, it has an EEPROM for storing various data including the ID code of the vehicle. The data output terminal of the microcomputer 11 is connected to the data input terminal of the transmitter 13. The signal output terminal of the transmission device 13 is connected to the antenna coil 14, and the data C supplied from the microcomputer 11 is output to the antenna coil 14 as a modulated signal.

As shown in FIG. 2, the antenna coil 14 is embedded in the IC card 2a in a loop shape. Further, the antenna coil 14 is connected to the signal input terminal of the receiving device 12, and receives the received signal.
The data output terminal of the receiving device 12 is connected to the data input terminal of the microcomputer 11, and the data D is supplied to the microcomputer 11. The receiving device 12, the transmitting device 13, and the antenna coil 14 constitute a transmitting / receiving means 15.
The IC cards 2b and 2c have the same electrical configuration except that the contents stored in the EEPROM inside the microcomputer are different depending on their applications.

On the other hand, the communication device 16 which is an external receiver,
For example, it is provided in an automobile 22 (see FIG. 3) as a vehicle. The power source of the communication device 16 is the battery 17 of the automobile 22, that is, the battery 17 is the microcomputer 1
8, the receiving device 19 and the processing device 20 are supplied with power. Like the microcomputer 11, the microcomputer 18 has an RO (not shown) for storing a control program therein.
It has M, a RAM for data processing, an EEPROM for storing various data including the ID code of the automobile 22, and the like.

The antenna coil 21 is the antenna coil 1.
4 and has a resonance frequency equal to 4, and is arranged in a loop shape at the peripheral portion of the door mirror 22a of the automobile 22, as shown in FIG. The antenna coil 21 is connected to the signal input terminal of the receiving device 19 and provides the received signal to the receiving device 19, and the receiving device 19 has its data output terminal connected to the data input terminal of the microcomputer 18. The data E is provided to the microcomputer 18. Further, the control terminal of the microcomputer 18 is connected to the control terminal of the receiving device 19, and the control signal E ′
Is supplied to the receiving device 19, and the output terminal is connected to the input terminal of the processing device 20, which is, for example, a door lock mechanism, and the control signal F is supplied to the processing device 20. The holder 1 and the IC card 2
a to 2c and the communication device 16 are the transmission / reception system 23.
Is composed.

Next, the operation of this embodiment will be described with reference to FIG. In the normal standby state before receiving the response signal, the microcomputer 18 of the communication device 16 uses the battery 17
4 (g), the receiving device 19 is set to the receiving state for a short time by intermittently setting the control signal E'to the high level in order to suppress the consumption. Further, in the normal standby state, the microcomputer 6 of the IC card 2a similarly stands by in a so-called sleep mode in which the frequency of the system clock is lowered in order to suppress the consumption of the battery 5. The same applies to the IC cards 2b and 2c.

The operator activates the start switch 4a.
When is pressed and the trigger signal A1 becomes high level for a moment (see FIG. 4A), the sleep mode of the microcomputer 6 is released, and the microcomputer 6 enters the normal operation state. Then, the microcomputer 6 reads the code of the activation signal corresponding to the IC card 2a from the internal EEPROM, converts the code into serial data, and gives it as the code data B to the transmitter 7 (see FIG. 4 (b)). ). The transmitter 7 modulates the code data B, gives it to the antenna coil 8, and transmits it from the antenna coil 8 as an activation signal of an electromagnetic induction signal which is an air propagation signal (see FIG. 4C).

When the activation signal is transmitted from the antenna coil 8, it is immediately received by the antenna coil 14 of the IC card 2a housed in the holder 1. Then, the received activation signal is given to the receiving device 12, and the receiving device 12 demodulates this and gives it to the microcomputer 11 as code data D similar to the code data B. Thus,
The microcomputer 11 is activated when the code data D is received, the sleep mode is released (see FIG. 4D), and the internal EEPROM stores in advance whether or not the code data D is transmitted to itself. Collation is performed by comparing the generated start signal code.

Although this processing is similarly performed for the IC cards 2b and 2c, since the activation signal codes do not match in this case, the processing returns to the sleep mode again. And I
For the C card 2a, the two match, so the internal E
The ID code of the automobile 22 is read from the EPROM, converted into serial data, and given to the transmission device 13 as ID data C. The ID data C is output to the antenna coil 14 and transmitted as a response signal of the electromagnetic induction signal by the transmitter 13 as described above.

Then, the holder 1 is brought close to the door mirror 22a of the automobile 22, and the antenna coil 2 of the communication device 16 in which the response signal is electromagnetically coupled to the antenna coil 14 is provided.
When the reception signal is received by No. 1 and the reception device 19 enters the reception state, the response signal is received and demodulated by the reception device 19, and the reception device 19 gives the data E to the microcomputer 18 (see FIG. 4 (f)).

The microcomputer 18 has I, which is the content of the data E.
When the D code is received, the ID code previously stored in the internal EEPROM is read out and collated with the received ID code. Then, the microcomputer 18 sets the control signal F to the high level and gives it to the processing device 20 if the two match. When the processing signal is supplied with the control signal F, the processing device 20 performs control processing such as unlocking the door (see FIG. 4 (h)). If the ID codes of the two do not match, the microcomputer 18 does not give the control signal F to the processing device 20, so that the processing device 20 does not perform the control processing.

The case where the IC card 2a, which is the electronic key of the three IC cards 2a to 2c, is activated and applied to the electronic key system of the vehicle has been described above. Similarly, the activation switch 4b is turned on. The IC card 2b, which is a commuter pass card, may be operated to be applied to the commuter pass system, or the start switch 4c may be turned on to activate the IC card 2c, which is an entrance certificate card, to be applied to the beginner check system. it can.

As described above, according to this embodiment, the holder 1
When the activation switch 4a is turned on by the operator, the microcomputer 6 is read out of the activation signal code for the IC card 2a as the electronic key and the activation signal is transmitted via the transmitter 7 and the antenna coil 8. Then
The microcomputer 11 of the IC card 2a is connected to the antenna coil 14
Also, it is configured to be activated when the activation signal is received via the receiving device 12 and to transmit the response signal to the communication device 16 side via the transmitting device 13 and the antenna coil 14.
Therefore, unlike the prior art, the communication device 16 does not need to always send the activation signal to the IC card 2a, and can reduce the power consumption of the battery 17 that is the power source. Further, the general-purpose non-contact type IC card can be used as it is in the transmission / reception system of the present invention without modification.

Further, according to this embodiment, the holder 1 has three
When the IC card 2a to 2c is configured to be housed therein and the activation signal is transmitted by the holder 1, each IC card 2a to 2c is an activation signal to which the activation signal is assigned. Since it is configured to transmit the response signal when it is determined that the activation signal is assigned to itself, one holder 1 can support a plurality of different systems.

The present invention is not limited to the embodiments described above and shown in the drawings, but the following modifications are possible. The number of IC cards stored in the holder 1 may be more or less than three, or may be only one. It may be configured that only one activation switch is used and which of the IC cards 2a to 2c is activated is selected depending on the number of times the switch is turned on within a predetermined time.

Three ICs are provided in the microcomputer 18 of the communication device 16.
Store all ID codes of cards 2a to 2c,
The control signal may be given to the processing device 20 regardless of which IC card is activated. The communication device 16 may have a transmitting means and may also be configured to transmit data to the IC card 2a. The antenna coil 14 is
It is also possible to dispose the antenna part including the bar antenna and the core behind the door handle part of the door panel of the automobile, and wind the bar part around the core of the antenna part.

The vehicle is not limited to an automobile, but can be applied to vehicles in general. Further, the invention is not limited to the electronic key system of the vehicle, the commuter pass, the introductory check system, etc., but can be generally applied to a system using an IC card for transmitting and receiving data by an airborne signal. The external receiver is
The effect of reducing the power consumption is effective not only for the communication device 16 provided in an automobile but also for a device installed indoors or the like and supplied with power from a commercial AC power supply. The airborne signal is not limited to the electromagnetic induction signal, and may be a radio wave, light, or electrostatic induction signal by appropriately changing the configuration.

[0027]

According to the transmission / reception system of the first aspect, when the activation switch of the holder is turned on while the IC card is attached to the holder, the activation signal is transmitted from the holder to the IC card by the air propagation signal. When the IC card receives the activation signal, the IC card transmits a response signal to the external receiver by an air propagation signal, and the external receiver executes a predetermined process when the response signal is received. Therefore, the external receiver only needs to perform the receiving operation in the standby state, and power consumption can be reduced.

According to the transmitting / receiving system of claim 2,
The holder selectively transmits a start signal corresponding to a plurality of different types of IC cards, and each IC card transmits a response signal when receiving a start signal assigned to itself, so that one holder Can support multiple different systems.

[Brief description of drawings]

FIG. 1 is a block diagram showing an electrical configuration of an embodiment of the present invention.

FIG. 2 is a perspective view of a holder and an IC card.

FIG. 3 is a diagram showing an antenna coil arranged in a door mirror of an automobile.

FIG. 4 is a timing chart.

[Explanation of symbols]

1 is a holder, 2a to 2c are IC cards, 4a to 4c
Is a start switch, 9 is a transmitting means, 15 is a transmitting / receiving means, 1
Reference numeral 6 denotes a communication device (external receiver), and 23 denotes a transmission / reception system.

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[Procedure amendment]

[Submission date] April 26, 1996

[Procedure amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0002

[Correction method] Change

[Correction contents]

[0002]

Such a transmission / reception system is also used, for example, in an electronic key system for a vehicle. Thus, the conventional electronic key system for vehicles is
An IC coil as an electronic key is provided with an antenna coil,
A card reader as an external receiver on the vehicle side is provided with an antenna coil that is electromagnetically coupled to the antenna coil of the IC card, and an inquiry signal is transmitted from the antenna coil of the card reader as an electromagnetic induction signal which is an airborne propagation signal. When the receiving antenna coil of the IC card, the I
The C card transmits an ID code signal unique to the vehicle as a response signal from the antenna coil, and the card reader reads the ID code transmitted from the IC card and uses the ID code stored in advance on the vehicle side. When they are compared with each other and compared with each other, the door is locked or unlocked, or the engine is started.

Claims (2)

[Claims] 1. A holder provided with a starting switch and a transmitting means for transmitting a starting signal as an airborne signal in response to an operation of the starting switch, and a holder mounted on the holder and having a transmitting / receiving means. An IC card that transmits a response signal as an airborne signal from the transmission / reception means when receiving a start signal from the transmission means of the holder, and an external receiver that executes a predetermined process when the response signal from the IC card is received. A transmission / reception system comprising: 2. The holder is configured to selectively transmit a start signal corresponding to a plurality of different types of IC cards, and each IC card responds when receiving a start signal assigned to itself. The transmitting / receiving system according to claim 1, wherein the transmitting / receiving system is configured to transmit a signal.