JPH03224799A - Data card - Google Patents

Abstract

PURPOSE:To write writing data in a non-contact state and to easily obtain a data card reduced in the effect on directionality by arranging a writing antenna so as to cross a reading antenna. CONSTITUTION:A writing antenna 21 arranged so as to cross a reading antenna 22 and receiving the writing data signal W3 transmitted from a data writer/ reader 17 in a non-contact state and writing the writing data DATAIN detected from the writing data signal W3 on a data memory 11 is provided to a data card 20 having the reading antenna 22 modulating the amplitude of a response command signal W1 composed of a microwave as a carrier wave on the basis of the data stored in the data memory to return the signal W1. By this constitution, the data card 20 capable of writing the writing data DATAIN on the data memory 11 in a non-contact state and reduced in the effect on directionality due to the the mutual action of the writing antenna 21 and the reading antenna 22 can be realized.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application The present invention relates to information cards, and is particularly suitable for application to information cards that can store written information signals in an information memory in a non-contact manner.

B. Summary of the Invention According to the present invention, by arranging the writing antenna and the reading antenna in an information card so as to cross each other, it is possible to realize an information card with less disturbance in directivity for both writing and reading.

C. Prior art As an information card reading device for reading information on a conventional information card, for example, 2.45 [GHz] is used as shown in Fig. 4.
A response request signal W1 using a microwave as a carrier wave is generated in the response request signal generation circuit 2 of the information reading device 1, and is emitted from the transmitting antenna 3 to the information card 4, and the response information signal is returned from the information card 4. By taking W2 into the response signal processing circuit 6 via the receiving antenna 5 of the information reading device 1, it is possible to detect the information card 4, for example, by a person entering or exiting the gate who carries the information card 4 as a person's exit card, or by cargo attached with the information card 4 as a tag. It is being considered to build an information card reading system that can check the information card.

The information card 4 that can be applied to such an information card reading system includes a dipole antenna 4B attached to a wiring board 4A to form part of a wiring pattern, and an information signal generation circuit 4C having an integrated circuit (IC) configuration. and the power supply battery 4D are connected by the wiring pattern 4E, and the impedance at the feeding point of the dipole antenna 4B is changed according to the information signal generated in the information signal generation circuit 4C, thereby generating a response request signal from the information reading device 1. It has been proposed that by changing the reflectance with respect to the carrier wave emitted as W1, the reflected wave is sent back as the response information signal W2 (Japanese Patent Application No. 63-62
No. 92).

The information signal generation circuit 4C has an electrical circuit configuration as shown in FIG. The address signal S3 of the address counter 13 that performs a counting operation is read out and supplied to the variable impedance circuit 14, which is made of, for example, a field effect transistor.

The variable impedance circuit 14 has a pair of feed point terminals TI
and 12, and thus, when the information data S1 becomes logic "1" or logic "0", the field effect transistor turns on or off, so that the feed point terminal T
The impedance at the feeding point of the dipole antenna 4B connected to T1 and T2 is variably controlled, and thus the reflectance for the response request signal W1 incident on the dipole antenna 4B is variably controlled.

A power supply battery 4D is connected between the ground side feed point terminal TI and the power supply terminal T3 of the information signal generation circuit 4C, and thereby the impedance variable control at the feed point of the dipole antenna 4B is always and continuously performed using the information data S1. It is made to be obtained.

A unique identification code is assigned to each information card 4 in the information memory 11, so that the information reading device 1 can reliably read the information held by the information card 4.

D Problems to be Solved by the Invention By the way, as a conventional method for writing information into the information memory 11 of the information card 4, for example, a write-only terminal is provided on the information card 4, and a connection terminal of an external device is brought into direct contact with the terminal. However, with this input method, the write-only terminal is exposed to the outside, resulting in poor contact due to dirt and oxidation of the terminal, and problems with the reliability of the information card 4. was there.

As a method to solve this problem, as shown in Figure 4,
Writing antenna 15 consisting of a 72-wavelength dipole antenna
is arranged in parallel with the reading antenna 16, for example, at the same frequency as the response request signal (i.e. 2.45 CGlh).
Alternatively, information transmitted from the information writing/reading device 17 as a writing information signal W3 using a carrier wave of a different frequency is received by the writing antenna 15, and the received signal S4 is transmitted by a received signal detection circuit comprising a Schottky diode 18. Write information data D by half-wave rectification
An information card 14 that demodulates the signal into A IN and writes it into the information memory 11 is conceivable.

However, if the write antenna 15 and the read antenna 16 are arranged in parallel in this way, the two antennas may interact with each other, causing disturbance in the directivity and a decrease in the output level of the received signal S4. was there.

The present invention has been made in consideration of the above points, and it is an object of the present invention to propose an information card that allows information to be written into an information memory without contact and has less disturbance in directivity.

E Means for Solving Problem E To solve this problem, in the present invention, the response request signal W1 using a microwave as a carrier wave is amplitude-modulated based on information data stored in the information memory 11 and sent back. An information card 20 having a reading antenna 22 that
is arranged to intersect with the reading antenna 22, and receives the write information signal W3 transmitted from the information writing/reading device 17 in a non-contact manner, and writes the write information data D detected from the write information signal W3. Information memory 11
A write antenna 21 is provided to be stored in the antenna.

By providing the F-action writing antenna 21 and arranging the writing antenna 21 to intersect with the reading antenna 22, the writing information data D A T A r is written in the information memory 11.
It is possible to realize an information card 20 in which N can be written in a non-contact manner, and the directivity is less affected by interaction between the write antenna 21 and the read antenna 22.

G example An embodiment of the present invention will be described in detail below with reference to the drawings.

(G1) First Embodiment In FIG. 1, in which parts corresponding to those in FIG. 4 are denoted by the same reference numerals, 20 indicates an information card as a whole, and a write antenna 21 and a read antenna are each made of a dipole antenna. 22 are arranged so as to be orthogonal to each other.

The write antenna 21 receives the write information signal W3 amplitude-modulated and transmitted from the information write/read device 17, and sends the received signal S4 to the Schottky diode 18. Received signal S
4 is subjected to half-wave rectification, and then converted into write information data DATA, .

The information signal processing circuit 23 includes an information memory 11 (FIG. 4), and stores input write information data DATA
n is stored in the information memory 11, and the information memory 11
Read the information data stored in the information data D A
The signal is sent to the variable impedance circuit 14 as T A out, and the reflectance of the reading antenna 22 is variably controlled.

The power supply battery 24 is a rectangular paper-type lithium battery, and is arranged symmetrically with respect to the long axis direction in another area where the write and read antennas 21 and 22 are not arranged. .

In the above configuration, before using the information card 20,
Memory data is written into the information memory 11 from the information writing/reading device 17. That is, when the information writing/reading device 17 gives the writing information signal W3 to the information card 20, the information card 2
0 receives the write information signal W3 at the write antenna 21 without contact, demodulates the detected received signal S4 after half-wave rectification into write information data DATAIN, and writes it into the information memory 11. .

The memory data thus stored in the information memory 11 is always and continuously read out from the information memory 11, and the variable impedance circuit 14 is variably controlled according to the logical value of the output information data DAT Aouy, and the reading antenna 2
By variably controlling the reflectance of 2, the response request signal W1 emitted from the information writing/reading device 17 is amplitude-modulated and sent back to the information writing/reading device 17 as a response information signal W2.

According to the above configuration, by arranging the write antenna 21 orthogonally to the read antenna 22, it is possible to reduce the influence on each other's directivity, and the write antenna 21
1 and the reading antenna 22 can be prevented from producing directivity in a specific direction, and write information data DATAIN can be written in the information memory 11 without contact.

Further, according to the above-described embodiment, it is possible to effectively avoid deterioration in performance due to a decrease in the signal levels of the received signal S4 and the response information signal W2 due to the interaction between the write antenna 21 and the read antenna 22. The data writing/reading distance can be extended.

Furthermore, according to the above-described embodiment, the metal surface of the paper-type lithium battery is The writing and reading antennas 2 act on the writing antenna 21 and the reading antenna 22.
It is possible to effectively suppress occurrence of undesirable directivity in signals 1 and 22 and reduction in signal levels of received signal S4 and response information signal W2.

(G2) Other Embodiments (1) In the above embodiments, a case was described in which the variable impedance circuit 14 was provided outside the information signal processing circuit 23. It may be built into.

(2) In the above embodiment, a case was described in which two sets of linear dipole antennas are arranged orthogonally, but in the present invention, instead of this, two sets of dipole antennas in a figure 7 shape are arranged. You can do it like this.

(3) In the above-described embodiment, a case has been described in which the writing antenna 21 and the reading antenna 22 are disposed orthogonally, but the present invention is not limited to this. Also good.

(4) In the above embodiment, a case was described in which a linearly polarized chromatic wave was transmitted to the information card 4.
The present invention is not limited to this, but if an antenna that transmits circularly polarized waves is used as an antenna that transmits microwaves, the influence on directivity can be suppressed more effectively than in the case of linearly polarized waves.

H Effects of the Invention As described above, according to the present invention, by arranging the write antenna so as to intersect with the read antenna, it is possible to write write information data in a non-contact manner, and the directivity is not affected. Information cards with little impact can be easily obtained.

[Brief explanation of drawings]

FIG. 1 is a plan view showing an embodiment of the information card according to the present invention, FIGS. 2 and 3 are block diagrams explaining a conventional information card, and FIG. 4 is a non-contact writing type. FIG. 3 is a route plan view for explaining an information card. 14.20... Information card, 15.21...
...Writing antenna, 16. 22... Reading antenna, 23... Information signal processing circuit, 24... Power supply battery. Agent Keiki Tanabe

Claims (1)

[Scope of Claims] An information card having a reading antenna that amplitude-modulates and sends back a response request signal using a microwave as a carrier wave based on information data stored in an information memory, which intersects with the reading antenna. A writing antenna is provided, which receives a writing information signal transmitted from an information writing/reading device in a non-contact manner, and stores writing information data detected from the writing information signal in an information memory. An information card featuring: