JP2006072678A - Contactless electronic device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem wherein a contactless electronic device equipped with a plurality of information transmission means, when using an information transmission means other than internal default information transmission means, causes determination of the information transmission means to cause a communication error and accordingly extend communication time. <P>SOLUTION: A contactless electronic device, equipped with a plurality of information transmission means for exchanging information signals with external devices detects the time width of a logical value constituting an information signal sent from an external device to determine the information transmission means that the external device is using by the header of the information signal, and can switch to the information transmission means for preventing communication errors and preventing extension of communication time. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a contactless electronic device that exchanges information via an external device and an antenna, and more particularly to a technique suitable for a contactless electronic device that includes a plurality of information transmission means.

  A so-called contactless electronic device having a semiconductor integrated circuit device and an antenna mounted in a card exchanges information between an external device and the semiconductor integrated circuit device, and transmits data held by the contactless electronic device. Implements various functions such as holding data sent from external devices.

In recent years, there has been an increasing demand for higher functionality of the non-contact electronic device, and studies have been made to realize various functions.
For example, as shown in [Patent Document 1], in an information recording medium equipped with a plurality of information transmission means, information transmission means switching means capable of switching the information transmission means according to the usage frequency counted by the usage frequency counting means Is one of them.

JP 2000-163538 A

ISO / IEC-14443 Type-B ISO / IEC-18092 212 kbps and 424 kbps

  The information transmission means described in [Non-Patent Document 1] is an information transmission means based on a so-called amplitude modulation method in which the amplitude of a high-frequency AC signal is partially modulated by an information signal, and the information signal is NRZ-L. The information signal is added with SOF at the beginning and EOF at the end.

  The information transmission means described in [Non-Patent Document 2] is an information transmission means based on a so-called amplitude modulation system in which the amplitude of a high-frequency AC signal is partially modulated by an information signal. It is to be encoded.

  In the information transmission means described in [Non-Patent Document 1] and [Non-Patent Document 2], when the information transmission means is switched by the information transmission means switching means described in [Patent Document 1], the usage frequency When the information transmission means selected by the usage frequency counted by the counting means matches the information transmission means used by the external device, communication is normally performed.

  However, if the information voltage means determined by the usage frequency counted by the usage frequency counting means and the information transmission means used by the external device do not match, the first transmission data from the external device cannot be normally received. Therefore, it switches to the other information transmission means and starts receiving again. If the information transmission means used by the external device can be matched by this switching operation, the transmission data from the second and subsequent external devices can be normally received.

  Therefore, when the information transmission means is switched by the information transmission means switching means described in [Patent Document 1], it is possible to reduce the probability of communication failure by counting the usage frequency. However, when using an information transmission means with low usage frequency, the first data transmitted by the external device cannot be received in order to determine the information transmission means. As a result, there is a problem that the external device needs to transmit the same data again, and the communication time is extended.

  An object of the present invention is an information transmission means capable of switching a plurality of information transmission means without causing a communication error with respect to data transmitted from an external device regardless of the frequency of use of the information transmission means. It is to provide a switching means.

  The outline of a typical invention among the inventions disclosed in the present application will be briefly described as follows. In other words, it is a non-contact electronic device equipped with a plurality of information transmission means for transmitting information to and from an external device, and by detecting a time width of a logical value constituting information transmitted from the external device, This is a non-contact electronic device having a function of discriminating information transmission means used by an external device and switching to one of the information transmission means.

  The effects obtained by the representative ones of the inventions disclosed in the present application will be briefly described as follows. That is, the non-contact electronic device according to the present invention can determine the information transmission means used by the external device at the head portion of the information transmitted from the external device, and the information transmission used by the external device. There is no communication error that occurs to determine the means, and it is possible to prevent the communication time from being extended.

  Hereinafter, a non-contact electronic device according to the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a block diagram of a basic configuration showing a first embodiment of the non-contact electronic device of the present invention.
In FIG. 1, U1 is a non-contact electronic device, U2 is a semiconductor integrated circuit device mounted on the non-contact electronic device U1, and L1 is an antenna mounted on the non-contact electronic device U1. The capacitor C1 connected in parallel with the antenna L1 forms a resonance circuit. The semiconductor integrated circuit device U2 has antenna terminals LA and LB for connecting the power supply circuit U3, the internal circuit U4, and the antenna L1.

  FIG. 2 shows the structure of the non-contact electronic device U1. The non-contact electronic device U1 is in the form of a card by a printed circuit board U11 molded with resin. The antenna L1 that receives an electromagnetic wave from the external device U14 is configured by a spiral coil U12 formed by wiring of the printed circuit board U11. A semiconductor integrated circuit device U2 configured by one IC chip U13 is mounted on a printed circuit board U11, and a coil U12 serving as an antenna is connected to the IC chip U13.

The antenna L1 that has received the electromagnetic wave from the external device U14 outputs a high-frequency AC signal to the antenna terminals LA and LB. The AC signal is partially modulated by an information signal (data).
The present invention is typically applied to a non-contact electronic device having no external and input / output terminals on the surface of the card, a so-called non-contact type IC card. Of course, it may be used for a dual type IC card having a non-contact interface and input / output terminals.
Further, although not particularly limited, the semiconductor integrated circuit device U2 is formed on a single semiconductor substrate such as single crystal silicon or the like by a known semiconductor integrated circuit device manufacturing technique.

In FIG. 1, the power supply circuit U3 basically includes a rectifier circuit U5 and a smoothing capacitor. Of course, a regulator U6 for controlling the voltage VDD output from the power supply circuit U3 so as not to exceed a predetermined voltage level may be provided.
The voltage VDD output from the power supply circuit U3 is supplied as the power supply voltage VDD of the internal circuit U4. The internal circuit U4 includes a receiving circuit U7, a transmitting circuit U8, a signal processing unit U9, and a memory U10. The receiving circuit U7 demodulates the information signal superimposed on the AC signal received by the antenna L1 provided in the non-contact electronic device and supplies the demodulated information signal to the signal processing unit U9 as a digital information signal.

  The transmission circuit U8 receives the information signal of the digital signal output from the signal processing unit U9, and modulates the AC signal received by the antenna L1 with the information signal. The external device U14 receives the information signal from the signal processing unit U9 in response to the reflection of the electromagnetic wave from the antenna L1 being changed by the modulation. The memory U10 is used for recording information data and transmission data demodulated with the signal processing unit U9.

  FIG. 3 is an example of signal waveforms in the information transmission means described in [Non-Patent Document 1] and [Non-Patent Document 2]. (A)-(D) have shown the signal waveform example in the information transmission means described in [nonpatent literature 2], (A) is the information signal (data) transmitted from an external device being "11. (B) is a signal waveform when the information signal (data) transmitted from the external device is “00”, and (C) is an information signal (data) transmitted from the external device. Signal waveform when “01”, (D) is a signal waveform when information signal (data) transmitted from an external device is “10”, and (E) is described in [Non-Patent Document 1]. In the information transmission means, the SOF signal waveform added to the head of the data transmitted from the external device is shown.

  Here, the Manchester code used in the information transmission means described in [Non-Patent Document 2] is information in which the first half of the information signal (data) is a logical value “0” and the second half is a logical value “1”. The signal (data) indicates “0”, the first half of the information signal (data) indicates the logical value “1”, and the second half indicates the information signal (data) “1”.

Further, (A) to (D) show signal waveform examples when the data transmission rate is 212 kbps, and (E) shows signal waveform examples when the data transmission rate is 847 kbps.
As shown to (A)-(D), the information transmission means described in [nonpatent literature 2] uses Manchester code as an encoding system. Thus, the maximum time width T1 in which the logical value “0” continues is (1 / 212k) seconds.

On the other hand, as shown in (E), the information transmission means described in [Non-Patent Document 1] has SOF added to the head of the data, and the time width T2 of the logical value “0” constituting this SOF is: It becomes (10 / 847k) seconds or more and (11 / 847k) seconds or less.
Accordingly, the time width T2 in which the logical value “0” constituting the SOF in the information transmission means described in [Non-Patent Document 1] continues is an external device in the information transmission means described in [Non-Patent Document 2]. It can be seen that the logical value “0” constituting the data transmitted from is larger than the continuous time width.

In the above description, the case where the data transmission rate of [Non-Patent Document 2] is 212 kbps and the data transmission rate of [Non-Patent Document 1] is 847 kbps has been described, but described in [Non-Patent Document 1] and [Non-Patent Document 2]. The same relationship holds for other data transmission rates.
Therefore, by detecting the difference in the pulse width constituting this information signal (data), the information transmission means described in [Non-Patent Document 1] and the information transmission means described in [Non-Patent Document 2] And the information transmission means can be switched according to the detection result.

FIG. 4 is a flowchart showing the switching operation of the information transmission means switching means included in the receiving circuit U7 mounted on the non-contact electronic device of the present invention.
The non-contact electronic device generates an internal power supply by the electromagnetic wave supplied from the external device, signal processing is started, and the transmission data from the external device can be received (F1). When transmission data from the external device is input, the process proceeds to F2, and a continuous time of a logical value “0”, that is, a so-called pulse width is monitored.

  In F2, if the pulse width of the logical value “0” is equal to or greater than the desired pulse width, it is determined that the information transmission unit used by the external device is the information transmission unit described in [Non-Patent Document 1], and F3 Proceed to In F3, the reception process 1 is started, and after receiving the final data, the process proceeds to F4 to determine whether or not the reception was successful. If it has been received normally, the process proceeds to F7 and reception is completed. If it cannot be received normally, it transits to a receivable state again.

On the other hand, if the pulse width of the logical value “0” is less than the desired pulse width in F2, the information transmission means used by the external device is determined to be the information transmission means described in [Non-Patent Document 2]. , Go to F5. In F5, the reception process 2 is started, and after receiving the final data, the process proceeds to F6 to determine whether or not the data has been normally received. If it has been received normally, the process proceeds to F7 and reception is completed. If it cannot be received normally, it transits to a receivable state again.
Here, the pulse width of the logical value “0” detected in F2 may be set from the relationship shown in FIG.

  With the above-described operation, the information transmission means can be switched at the head of the signal received by the non-contact electronic device. As a result, a communication error due to a mismatch between the information transmission means set in the non-contact electronic device and the information transmission means used by the external device does not occur. Therefore, even if a function for switching information transmission means is added, the communication time is not extended.

FIG. 5 shows a fourth embodiment of the portable information terminal of the present invention in which any one of the non-contact electronic devices according to the first embodiment is incorporated.
In FIG. 5, U15 is a mobile phone which is a portable information terminal, U16 is a foldable casing of the mobile phone U15, U17 is an input device for inputting data provided on the inner surface of the main body of the casing U16, and U18 is a casing. A non-contact electronic device arranged on the back side of the input device U19 is arranged inside U16. Although not shown in FIG. 5, a display device is disposed on the inner surface of the lid of the housing U16. In addition, a transmission / reception circuit and a data processing circuit for performing communication by voice or data are disposed inside the lid of the housing U16. Data input / output to / from the data processing circuit is displayed on the display device.

The non-contact electronic device U18 has a terminal for outputting data and a terminal for inputting a power supply voltage, and is connected to the data processing circuit via these terminals. The data of the internal circuit of the non-contact electronic device U18 can be displayed on the display device by operating the input device U17.
Further, when the non-contact electronic device U18 is placed in the vicinity of the external device U14, the non-contact electronic device U18 transmits and receives data to and from the external device U14 regardless of whether the cellular phone U16 is turned on. Note that the non-contact electronic device U18 may be incorporated in the mobile phone U15 in a detachable manner.

According to the present embodiment, it becomes possible to know the data of the non-contact electronic device U18 without using an external device, and the convenience of the non-contact electronic device U18 can be improved.
In the present embodiment, the non-contact electronic device U18 is built in the mobile phone U15, but can be built in any other portable information terminal such as a notebook personal computer or a notebook personal computer.

Although the invention made by the present inventor has been specifically described based on the embodiments, it is needless to say that the present invention is not limited to the above embodiments and can be variously modified without departing from the gist thereof. Yes.
For example, in FIG. 3, the Manchester code used in the information transmission means described in [Non-Patent Document 2] is configured such that the first half of the information signal (data) is a logical value “0” and the second half is a logical value “1”. "1" of the information signal (data) to be transmitted, the first half of the information signal (data) represents the logical value "1", and the second half represents the "0" of the information signal (data) composed of the logical value "0" It may be a thing.

  In the contactless electronic device of FIG. 1, the power supply circuit, the receiving unit, the transmitting unit, the signal processing unit, and the memory may be configured by a plurality of semiconductor integrated circuit devices. The present invention can be widely used for semiconductor integrated circuit devices and non-contact electronic devices having a plurality of information transmission means.

  The present invention is suitable for application to an IC card or the like, and can be widely used for transportation, finance, transportation, commerce, and the like.

1 is a basic configuration diagram of a first embodiment of a semiconductor integrated circuit device and a non-contact electronic device according to the present invention. The perspective view of the wiring board and external device of a non-contact electronic device which have an antenna and the semiconductor integrated circuit device of this invention. The example of a signal waveform in the information transmission means described in [nonpatent literature 1] and [nonpatent literature 2]. The flowchart which shows the switching operation | movement of the information transmission means switching means which the receiving circuit U7 mounted in the non-contact electronic device of this invention has. The bird's-eye view of the mobile telephone for demonstrating a 2nd Example.

Explanation of symbols

C1 ... Resonant capacity, L1 ... Antenna, LA, LB ... Antenna connection terminal, T1, T2 ... Time width, U1 ... Non-contact electronic device, U2 ... Semiconductor integrated circuit device, U3 ... Power supply circuit, U4 ... Internal circuit, U5 ... Rectifier circuit, U6 ... Regulator, U7 ... Receiver circuit, U8 ... Transmitter circuit, U9 ... Signal processor, U10・ ・ ・ Memory, U11 ... Printed circuit board, U12 ... Coil, U13 ... IC chip, U14 ... External device, U15 ... Mobile phone, U16 ... Folding type of mobile phone U17 Case, U17 ... input device, U18 ... non-contact electronic device, VDD ... power supply voltage.

Claims (3)

A non-contact electronic device equipped with a plurality of information transmission means for transmitting information to and from an external device,
By detecting the time width of the logical value that constitutes the information transmitted from the external device,
Determine the information transmission means used by the external device,
A non-contact electronic device having a function of switching to one of information transmission means. The contactless electronic device according to claim 1,
The plurality of information transmission means mounted on the non-contact electronic device includes:
A non-contact electronic apparatus, characterized in that it is an information transmission means for partially modulating a high-frequency AC signal with an information signal by the same modulation method. The contactless electronic device according to claim 1 or 2,
The plurality of information transmission means mounted on the non-contact electronic device includes:
A non-contact electronic device which is an information transmission means for modulating the amplitude of a high-frequency AC signal partially by an information signal.

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