JP2003248799A - Ic card reader-writer, identification method and its program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an IC card reader-writer, an identification method and its program capable of speedily completing an identification process of each noncontact IC card. <P>SOLUTION: This invention provides the reader/writer, the identification method and the program comprising a response-detection means for detecting normal responses and collisions from IC cards in response to a request; and a response-invalidation means of sending a response-invalidation command, which is a command not to respond to requests in the future, to the IC cards that sent normal responses when the response-detection means received normal responses from the IC cards even though collisions were detected. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an IC card reader / writer, an identification method, and a program therefor. More specifically, the present invention relates to an IC card identification using time slots.
The present invention relates to a C card reader / writer, an identification method, and a program thereof.

[0002]

2. Description of the Related Art Conventionally, a time slot system has been adopted for communication between a non-contact IC card for exchanging data using an electromagnetic induction system and a reader / writer for identifying the non-contact IC card. . This is because when a plurality of non-contact IC cards exist simultaneously in the communicable area of the reader / writer and a plurality of non-contact IC cards simultaneously respond to polling from the reader / writer, each response signal used for the response. This is because any of the non-contact IC cards cannot normally communicate with the reader / writer due to the collision.

The time slot communication method will be described below.

(1) First, an IC card reader / writer (hereinafter referred to as a reader / writer) sends an initial response request command as a request to the non-contact IC card in order to confirm the existence of the non-contact IC card. The initial response request command includes a "slot number" required for controlling the timing of the initial response performed by the non-contact IC card, or a value required for calculating the "slot number".

(2) After receiving the initial response request command, the non-contact IC card returns the initial response (response) using a time slot provided from a specific time. The time slot used for the response, that is, the timing is determined by the non-contact IC card itself by a random number.

(3) When the reader / writer detects a collision of responses that occurs when a plurality of non-contact IC cards select the same time slot, the reader / writer again transmits the initial response request.

(4) The reader / writer recognizes all contactless IC cards by receiving responses from all contactless IC cards without collision, and completes the sequence for identifying the cards. .

The above processing will be described in more detail with reference to FIGS. The following is the international standard ISO / IEC (Internationa
l Organization For Standardization / International E
This is processing of a non-contact IC card when it is applied to the Electrical Technical Commission) 14443.

The ISO / IEC14443 can be applied to, for example, a contactless telephone card. More specifically,
As shown in FIG. 16, it is assumed that three non-contact IC cards 1601, 1602, 1603 having a function as telephone cards are simultaneously inserted (closed) to a reader / writer 1600 which functions as a public telephone.

In the contactless IC card identification system of ISO / IEC14443, the contactless I
The C card is identified.

First, the reader / writer 160 which is a public telephone
0 sends an initial response request (request). The initial response request has a format shown in FIG. 18, and among the 8 bits in the PARAM 1802 forming the initial response request 1801, bits 1 to
The number of time slots (N) is notified to each contactless IC card using 3 bits 1803 of bit 3. In addition, APf1
Reference numeral 804 denotes a header indicating an initial request command, which is AF
I1805 indicates the applicable class of the contactless IC card.
Also, CRC (Cyclic Redundancy Check) 1806 is A
It is a CRC from Pf to PARAM.

Although the non-contact IC card responds with N slots from 1 to N, the number of time slots (N) will be described as 4 in this description. That is, in response to the initial response request, the non-contact IC cards 1601-1603
Selects one of the time slots 1 to 4,
Give a response.

First card identification processing 17 shown in FIG.
In 01, the reader / writer 1600 first transmits an initial response request R1 [REQB] (1702). It is assumed that the non-contact IC cards 1601 and 1602 generate “1” as random numbers and the non-contact IC card 1603 generate “2” as random numbers in response to the initial response request R1 (1702). In this case, non-contact I
The C cards 1601 and 1602 have time slots 1 (1
Responses [ATQB] A21 and A31 shown in 703) are made respectively. Also, a non-contact IC card 1603
Is the response A4 shown in time slot 2 (1704).
Respond with 1. In the above case, since the non-contact IC cards 1601 and 1602 both respond at the same timing, the reader / writer 1600 causes the time slot 1 (17).
The collision of the response of the non-contact IC card in 03) is detected. Therefore, the non-contact IC cards 1601 and 16
Since 02 cannot be identified, the identification process is restarted.

Then, in the second identification processing 1705, the reader / writer 1600 makes an initial response request R2.
(1706) is transmitted. If it is assumed that the non-contact IC card 1601 and the non-contact IC card 1603 generate “1” as a random number and the non-contact IC card 1602 generates “3” as a random number in response to the initial response request. The IC cards 1601 and 1603 respond using the packets A22 and A42 in the time slot 1 (1707), respectively. In addition, the non-contact IC card 160
2 is packet A3 in time slot 3 (1708)
Respond with 2. In this case, the reader / writer 1600
Is a non-contact IC in time slot 1 (1707)
The collision of the responses of the cards 1601 and 1603 is detected. Therefore, since the reader / writer 1600 cannot identify the non-contact IC cards 1601 and 1603, it restarts the identification process.

Subsequently, in the third identification processing 1709, the reader / writer 1600 makes an initial response request R3.
(1710) is transmitted. Here, in response to the initial response request, the non-contact IC card 1601 uses “1” as a random number,
It is assumed that the non-contact IC card 1602 has generated “3” as a random number and the non-contact IC card 1603 has generated “4” as a random number. In this case, the non-contact IC card 1601 is in packet A23 in time slot 1 (1711), the non-contact IC card 1602 is in packet A33 in time slot 3 (1712), and the non-contact IC card 1603 is in time slot 4 (1713). Of the packet A43. Therefore, the reader / writer 1600
Does not detect a collision, all the non-contact IC cards can be identified and the identification process is completed. The above is I
This is a card identification process for a non-contact IC card according to the regulations of SO / IEC14443.

Here, after the power of the non-contact IC card is turned on (from entering the communicable distance with the reader / writer) until each non-contact IC card is identified by the reader / writer, an idle period + ready. It can be positioned as a period.

On the other hand, when all the contactless IC cards are identified, the reader / writer sends an "ATTRIB" command to each contactless IC card. This indicates the transition from the idle period + ready period to the active period, and each of the non-contact IC cards has "ATTRI".
When the "B" command or the like is received to enter the active period, various communication with the reader / writer becomes possible. Note that each contactless IC card that has entered the active period does not respond to the initial response request command. Then, instead of the above-mentioned "ATTRIB" command, for example, "H"
When the ALT "command is received, the above contactless IC
The card shifts to the halt period and does not communicate with the reader / writer. In this case, the reader / writer is "WA
By transmitting the KE-UP "command, the contactless I
The C card shifts to the active period, and communication becomes possible.

According to the regulations of ISO / IEC14443, the time when the contactless IC card responds in the time slot 1 after receiving the initial response request command is 302 μsec, and the period of one time slot ( The time) is specified as 2266 μsec. That is, the timing from receiving the initial response request from the reader / writer 1600 until transmitting the response (μ
sec) is given by the following calculation formula (Formula 1).

Timing (μsec) = 302 μsec + 2266 μsec × (number of slots (N) −1): (Equation 1) As a method similar to the time slot method, there is a slot marker method. The slot marker method is a method in which the reader / writer transmits an initial response request in the time slot method, and then the reader / writer transmits a slot marker command indicating the start of a slot at each slot start timing. Therefore, it is essentially the same as the time slot system in that each IC card responds by using the time slot designated by the reader / writer to recognize each IC card.

Further, a non-contact IC due to the collision of the above responses
A technique for avoiding a delay in the card identification process is disclosed in Japanese Patent Laid-Open No. 2000-298712.

In the technique disclosed in the above-mentioned Japanese Patent Laid-Open No. 2000-298712, the time slots in which a collision has occurred are counted by confirming the collision of responses in each time slot, and the number of time slots in which the collision has occurred is counted. Based on this, the number of time slots is increased or decreased.

[0022]

[Patent Document 1] Japanese Patent Laid-Open No. 2000-298712

[0023]

A non-contact IC card (international standard ISO /
In the IEC14443-compliant non-contact IC card or the like), when the non-contact IC card makes a response to the reader / writer, the non-contact IC card itself selects a time slot using a random number. Therefore, for example, when the random numbers generated by a plurality of non-contact IC cards are the same, the selected time slots are the same, and the responses always collide. In this case, the reader / writer needs to re-transmit the response request command to perform the contactless IC card identification process, and as a result, the contactless IC card identification is delayed.

Further, in the technique disclosed in Japanese Patent Laid-Open No. 2000-298712, the contactless IC card is increased by increasing the number of time slots designated by the reader / writer based on the number of time slots in collision. Lowers the probability of choosing the same time slot. However, in the above technique, it is necessary to judge the presence or absence of collision of responses in each time slot and count and store the number of collisions each time, which complicates the configuration of the reader / writer. If the number of time slots is changed (increased) and identification processing is started, and the number of collision occurrences is reduced even though the number of non-contact IC cards is not changed, next time the number of time slots is reduced and identification is performed. Since the processing is performed, there is a problem that the frequency of collision increases again and the identification processing time becomes long.

The problem that the identification processing time commonly seen above is delayed is a system in which a user needs to identify a non-contact IC card to a reader / writer without stopping, such as a ticket gate of a train. Appears remarkably. That is, the delay in the identification of the non-contact IC card causes the user to stop, which results in an obstacle to the use of the system.

In the future, the non-contact I will be used in various fields.
It can be expected that various systems will be introduced that take advantage of the convenience of the C card. That is, it can be easily predicted that the number of non-contact IC cards owned by one user (for example, in a wallet) will increase as time passes. Under such circumstances, the problem of delay becomes more serious because the identification processing time becomes longer. Therefore, even in the sense of extending the useful life of each system,
It is necessary to prepare for the above situation in advance.

On the other hand, if the non-contact IC card can be identified at high speed, the non-contact IC card can be applied to a moving object at a higher speed. However, further speeding up of the above identification processing is desired.

It is an object of the present invention to provide an IC card reader / writer, an identification method, and a program for completing the identification processing of each non-contact IC card at high speed.

[0029]

The present invention employs the following means in order to achieve the above object. That is, the present invention is premised on an IC card reader / writer that communicates with a plurality of IC cards. Here, the response detecting means detects a normal response to the request from the IC card and a collision of the responses, and the response invalidating means detects that the response detecting means receives a normal response from the IC card. ,
An IC that sent a normal response even if the above collision was detected
A response invalidation command, which is a command not to respond to the subsequent request, is transmitted to the card.

Therefore, subsequent requests are transmitted only to the IC card that has transmitted the response causing the collision, that is, the probability that the responses collide in the subsequent identification processing is reduced, and the identification processing is completed at high speed. can do.

There is a configuration provided with a slot number increasing means for increasing the time slot number of the next request based on only the presence or absence of the collision detected by the response detecting means, and the slot number increasing means further invalidates the response. There is a configuration for increasing the number of time slots based on whether or not the response invalidation command is transmitted by the means, that is, whether or not the response invalidation is performed.

In this configuration, the IC card corresponding to the response that does not cause a collision performs the response invalidation process each time, so that the identification process is performed only on the IC card that causes the collision, and the time slot is appropriately set. Since the number of IC cards is increased, the identification can be flexibly and efficiently performed according to the number of IC cards even in a system that requires identification of a large number of IC cards.

The response invalidation command is ISO / IE.
"ATTRIB" command based on C14443, or "
It can be a HALT "command.

Further, the collision detecting means detects a collision of the response from the IC card to the request, and the slot increasing means serves as a reader / writer for increasing the number of time slots based on only the presence or absence of the collision detected by the collision detecting means. Good.

In this reader / writer, only the presence / absence of a collision of the response from the IC card is detected, and the time slot is increased based on only the presence / absence of the collision. Therefore, the reader / writer does not have to have a complicated structure. Identification can be efficiently performed according to the number of IC cards.

In this configuration, the number of time slots included in the first (first) request may be "1".

Further, the storage means stores the number of the IC cards when the plurality of IC cards are normally recognized,
The calculation unit calculates the number of time slots (initial value) included in the first request for identifying each IC card based on the number of IC cards stored in the storage unit, and the slot number resetting unit calculates The reader / writer may set the number of time slots calculated by the means as the number of slots at the time of the first request.

In this reader / writer, past I
The number of time slots can be dynamically changed based on the history of recognizing the C card, and the identification processing time of each card can be shortened with a high probability. At the same time, the service life of the system using the reader / writer can be extended.

The reader / writer can be embodied using a computer. In this case, the response detecting means, the response invalidating means, the slot number increasing means, the collision detecting means,
It is embodied by running a program on a computer.

[0040]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings to provide an understanding of the present invention.
It should be noted that the following embodiment is an example in which the present invention is embodied, and does not limit the technical scope of the present invention.

(First Embodiment) First, a reader / writer according to a first embodiment of the present invention will be described. FIG. 1 is a functional block diagram of the reader / writer 101 according to the first embodiment. Further, FIG. 2 shows the reader / writer 1 described above.
It is a hardware block diagram of 01.

The reader / writer 101 has an antenna 20.
3, a transmission / reception circuit 202, a CPU 201, and a ROM that stores a program for controlling the reader / writer
(Read Only Memory) 104, a RAM (Random Acces) used as a work area when the program is executed
s Memory) 205.

When the non-contact IC card that communicates with the reader / writer 101 enters the communicable area of the reader / writer 101, it operates with the electric power induced by the electromagnetic waves from the reader / writer.

When the reader / writer 101 is expressed by function, as shown in FIG. 1, it comprises an antenna means 107, a transmitting / receiving means 106, a control means 105, a response detecting means 102, and a response invalidating means 103. However, the details of the processing of each means will be described as appropriate.

Note that, for example, the response detecting means 102 and the response invalidating means 103 are stored in the ROM 104 as programs, and are read by the CPU 201 and executed as necessary.

Next, the processing of the reader / writer according to the first embodiment will be described with reference to FIGS. 1, 3, 4, and 5. FIG. 3 is a flowchart of the processing executed by the reader / writer 101. For the sake of understanding, it is assumed in the first embodiment that the three non-contact IC cards 410, 420, 430 communicate with the reader / writer 101 as shown in FIG.

First, the control means 105 constituting the reader / writer 101 transmits an initial response request 450 to the contactless IC card at predetermined time intervals (FIG. 3: S30).
1). The transmission of the initial response request is performed, for example, at intervals of several tens of milliseconds. Here, the reader / writer 101
The initial response request transmitted by the contactless IC card 41
When 0, 420, and 430 receive, each contactless IC card acquires the number of time slots included in the initial response request. The number of time slots is 3 bits 18 of Bit 1 to Bit 3 of PARAM shown in FIG.
It is specified by 03 and the value of 2 specified in this bit.
Is the time slot number.

Next, each of the above non-contact cards 410 to 430.
Selects one of the timeslot numbers given by the reader / writer 101 to determine the timeslot used for the response.

Subsequently, the non-contact IC card waits until a time slot (timing) for transmitting a response to the reader / writer, and transmits a response to the initial response request at (timing) the selected time slot. .

The response transmitted from the non-contact IC card is received by the control means 105 via the antenna means 107 and the transmission / reception means 106 which constitute the reader / writer 101. Here, the contactless IC card 410 sets the time slot 2 (451) to the contactless I card.
The C card 420 has time slot 3 (452), and the contactless IC card 430 has time slot 2 (451).
Suppose you have selected.

Under the above assumptions, the control means 105 is
Does not receive a response in time slot 1 (457), it sends a message to that effect to the response detecting means 102. Next, the control means 105 receives the responses 453, 455 of the contactless IC cards 410, 430 transmitted in the time slot 2 (451) and transmits the received response to the response detection means 102. . In addition, the control means 105
Receives the response 454 of the non-contact IC card 420 transmitted in time slot 3 (452) and transmits the received response to the response detecting means 102. further,
Since the control means 105 does not receive the response in the time slot 4 (458), the control means 105 sends a message to that effect to the response detecting means 102 (FIG. 3: S301).

The response detecting means 102, which has received the response corresponding to each time slot as described above, temporarily stores the response corresponding to each time slot in a predetermined storage means corresponding to each time slot. It detects (determines) whether each response is a “normal response” or a “collision”.

The process from the transmission of the initial response request to the determination of "collision" described above is the response determination process described in step S301 of FIG.

Here, the time slot 1 (45
7), the response corresponding to the time slot 4 (458) is not detected, but in the time slot 2 (451),
Since there is a response between the non-contact IC card 410 and the non-contact IC card 430, "collision" is detected.
In the time slot 3 (452), only the response from the non-contact IC card 420 is detected, so that it is detected as a "normal response".

Then, when the response detecting means 102 detects a "collision", the response invalidating means 103 constituting the reader / writer 101 is, for example, the response invalidating means 1.
"1" is set to the counter provided in 03 (FIG. 3: S302 YES → S303).

The response detecting means 102 causes a "collision".
If no is detected, it means that there is no communicable non-contact IC card within the communication range of the reader / writer 101, or that a response from each non-contact IC card has been received without any problem, and the processing of the response detection means 102 ends. (Figure 3: S3
02 NO → end). If a response is received, the control means 105 carries out the subsequent communication processes.

Now, when the response invalidating means 103 sets "1" in the counter, it then refers to the predetermined storage means corresponding to the time slot N (N is the value of the counter) indicated by the counter and refers to "1". It is determined whether "normal response" is stored.

Here, the time slot 1 (457)
Since the response is not recorded in the storage means corresponding to, it is then confirmed whether the number of time slots transmitted by the initial response request matches the value of the counter (FIG. 3: S304 NO → S306).

Next, the number of transmitted time slots and
If the counter values do not match, set the counter to 1
It is incremented and it is again determined whether or not the "normal response" is stored in the storage means corresponding to the time slot 2 (451) indicated by the next counter (FIG. 3: S304 →
S306 NO → S307 → S304).

When the above processing is repeated, under the above assumption, a normal response is stored in the storage means corresponding to the time slot 3 (452). In this case, the response invalidation unit 103 performs response invalidation processing (FIG. 3: S304).
YES (N = 3) → S305).

The response invalidation process is performed as follows. That is, the response invalidating unit 103 acquires the information unique to the non-contact IC card 420 by reading the content of the response from the storage unit corresponding to the time slot 3 (452). Then, the response invalidating means 103 sends the response invalidating command 446 including the unique information to the control means 105 and the transmitting / receiving means 10.
6 and the non-contact IC card 420 via the antenna means 107.

Here, the response invalidation command means that it does not respond to the initial response request transmitted from the reader / writer 101 until a command indicating the end of communication with the reader / writer 101 is received. Is a command that indicates. Specifically, for example, ISO / IEC14
“ATTRIB” command or ”defined in 443
A HALT "command or the like corresponds to this, but a command newly defined in the design of the reader / writer and the contactless IC card may be used.

The contactless IC card 420 that has received the response invalidation command does not respond to the initial response request until it receives a command indicating the end of communication with the reader / writer 101, but does not respond to the initial response request. Communication other than the above is performed, that is, the active period starts. However, when the "HALT" command is received, the normal period is not performed until the halt period is entered and the "WAKE-UP" command is received.

Now, in step (S306) of FIG. 3, when the number of time slots transmitted by the control means 105 matches the counter, it means that all responses have been determined, and the response determination processing is repeated again (FIG. 3: S3
06YES → S301) Subsequently, the reader / writer 101 that has invalidated the non-contact IC card 420 performs the second identification process 442. Even in the second identification process 442, the first identification process 4 is performed.
Performs almost the same processing as 41, but the non-contact IC card 42
Since 0 has already been invalidated, the non-contact IC card 410 and the non-contact IC are used in the second identification processing 442.
It suffices to identify the card 430.

That is, the reader / writer 101 transmits the initial response request 460. Although the initial response request is received by the non-contact IC cards 410 to 430, the non-contact IC card 420 is invalidated and thus does not respond.

Here, the contactless IC card 410 responds to the initial response request by the time slot 2 (461).
The contactless IC card 430 is a time slot 1
Suppose (462) is selected.

Under the above assumption, the control means 105 is
Receives the response 463 of the non-contact IC card 430 transmitted in the time slot 1 (462) and transmits the received response to the response detecting means 102. Further, the control means 105 receives the response 464 of the non-contact IC card 410 transmitted in the time slot 2 (461), and transmits the received response to the response detection means 102. Incidentally, the control means 105 controls the time slot 3
(465), since the response is not received in the time slot 4 (466), the fact is transmitted to the response detecting means 102.

That is, under the above assumption, the response detecting means 102 does not detect "collision", so that the reader / writer 10
1 can identify the non-contact IC cards 410 and 430 as in the conventional case. After that, the non-contact IC cards 410, 420, 430 identified by the reader / writer 101 are
It becomes possible to communicate with the reader / writer 101.

As described above, when the normal response is received, the response invalidating command is transmitted to the IC card which has transmitted the normal response even if the collision is detected. The identification processing is targeted only to the IC card that has transmitted the response causing the collision. That is, in the subsequent identification processing, the probability of collision of responses is reduced, that is, the identification processing can be completed at high speed.

The present invention may be applied to a reader / writer using a contact type IC card instead of the non-contact type IC card. Further, the present invention may be applied to a reader / writer using a slot marker method instead of the time slot method, or may be applied to a reader / writer using another slot method.

Further, the invalidation command includes a plurality of pieces of information unique to the non-contact IC card, so that even if the plurality of non-contact IC cards that have normally responded by one invalidation command are invalidated at the same time. Good.

(Second Embodiment) Next, a reader / writer 601 according to a second embodiment of the present invention will be described with reference to FIGS. 6, 7, and 8.

The reader / writer 601 in FIG. 6 has the same structure as the reader / writer 101 in the first embodiment, but the response detecting means 102 and the response invalidating means 10 are provided.
In place of 3, the collision detection means 602 and the slot number increase means 603 are provided. The details of each means will be described later. FIG. 7 is a flowchart of the processing executed by the reader / writer 601 according to the second embodiment.

First, for the sake of understanding, the situation shown in FIG. 5 will be taken as an example. That is, here, the reader / writer 6
01 is three different non-contact IC cards 410, 420,
Identification processing for identifying 430 is performed.

First, the control means 105 constituting the reader / writer 601 transmits an initial response request, and the number of time slots is set to "1" in the initial response request (FIG. 7: S701).

This is because, for example, in a reader / writer that communicates with a plurality of contactless IC cards, the number of contactless IC cards is not known in the first contactless IC card identification processing, so that the number of contactless IC cards that can communicate is one. Assuming that there is only one, the above "1" is set. By doing so, when communicating with a plurality of contactless IC cards, a collision of responses always occurs in the first identification processing, but since there is only one time slot, the first initial response The processing related to the request is completed in a short time. Therefore, in a reader / writer that often communicates with only one non-contact IC card, the identification process can be completed in a short time by setting the number of time slots to "1" in the first identification process. Become.

The control means 105, after setting the time slot number to "1", carries out the non-contact IC card identification process (FIG. 7: S702). That is, as shown in FIG. 8, the reader / writer 601 transmits the initial response request 803 in the first identification processing 801. The number of time slots set in the initial response request is "1"
Therefore, the non-contact IC cards 410, 420, 430
Can select only time slot 1 (802) for each response. That is, the response 80 of the non-contact IC card 410
4. Response 805 of non-contact IC card 420, non-contact IC
Response 806 of card 430 is time slot 1 respectively
(802) is transmitted.

The responses 804 to 806 are received by the control means 105 via the antenna means 107 and the transmission / reception means 106 which constitute the reader / writer 601. Next, the control means 105 transmits the responses 804 to 806 corresponding to the time slot 1 to the collision detection means 602. The collision means 602 determines from the content of the response corresponding to the time slot 1 whether the response corresponding to the time slot 1 includes “collision”.

Here, the response corresponding to the time slot 1 is detected as "collision" because it includes the responses 804 to 806 (FIG. 7: YES in S703).

When the collision detecting means 602 detects "collision", the fact is transmitted to the slot number increasing means 603, and the slot number increasing means 603 increases the number of time slots of the next initial response request. , The number of time slots is set to a value larger than “1”, that is, the number of time slots is increased (FIG. 7: S704).
Here, it is assumed that the number of time slots is set to "4".

When the slot number increasing means 603 sets the time slot number to "4", the control means 105
Transmits the initial response request 811 again in the second identification processing 807 (FIG. 7: S702).

Here, for example, the non-contact IC card 41 is used.
0 is the time slot 2 (809) for sending response 812
The non-contact IC card 420 transmits the time slot 4 (810) to the response 813 and the non-contact IC card 430 transmits the time slot 1 (80) to the response 814.
8) is selected.

The responses 812 to 814 are in the order corresponding to the time slots 1 to 4, that is, the response 814 and the response 81.
2, the response 813 is received by the control means 105 in this order, and then transmitted to the collision detection means 602.

Here, since no collision is detected by the collision detecting means 602, the time slot is not increased (FIG. 7: S703 NO → END). Of course, since the responses 812 to 814 are identified by the reader / writer as normal responses, each of the non-contact IC cards 410 to 43 will be hereafter described.
0 and the reader / writer 601 can communicate with each other.

As described above, only the presence or absence of the collision of the response from the IC card is detected, and the time slot is increased based on only the presence or absence of the collision. Therefore, the IC card can be added without adding a complicated structure to the reader / writer. The identification can be efficiently performed according to the number of.

The present invention may be applied to a reader / writer using a contact type IC card instead of the non-contact type IC card. Further, the present invention may be applied to a reader / writer using a slot marker method instead of the time slot method, or may be applied to a reader / writer using another slot method.

The increase in the number of time slots may be a fixed value or a variable value.

Further, in a reader / writer which is expected to communicate with a plurality of IC cards from the beginning, it is not always necessary to set the number of time slots of the first initial response request to "1", and the time corresponding to the reader / writer is set. The number of slots may be set.

(Third Embodiment) Next, referring to FIGS.
A reader / writer 901 according to the third embodiment of the present invention will be described with reference to FIGS. 11 and 12.

FIG. 9 has the same configuration as the reader / writer 101 in the first embodiment and the reader / writer 601 in the second embodiment, and has the function of the collision detection means 602 in the second embodiment as the response detection means. Prepare for 102. That is, the reader / writer 901 uses the response detection unit 1
02, response invalidating means 103, and slot number increasing means 603. FIG. 10 is a flowchart of the process executed by the reader / writer 901 according to the third embodiment. In each processing, the above-described first and second embodiments
The same numbers are given to the same processes as.

In the third embodiment, it is assumed that a contactless IC card 440 is further added to the situation shown in FIG. First, the reader / writer 90
1 is a non-contact IC card 410, 420, 430, 44
When communicating with 0, the control means 105 sets "1" to the number of time slots of the initial response request 1103 used in the first identification processing 1101 (FIG. 10: S70).
1).

Subsequently, when the control means 105 transmits the initial response request 1103, next, in response to the initial response request, each of the non-contact IC cards 410 to 440.
Responds (FIG. 10: S702). Since the number of time slots is set to "1" here, each non-contact IC
The responses 1104-1107 of the cards 410-440 are transmitted at the timing of time slot 1 (1102).
Therefore, the response detection unit 102 included in the reader / writer 901 detects that the response corresponding to the time slot 1 (1102) stored in the predetermined storage unit is “collision” (FIG. 10: S302 YES).

Incidentally, the response detecting means 102 causes a "collision".
Is not detected, it indicates that there is no communicable non-contact IC card within the communication range of the reader / writer 901, or that a response from each non-contact IC card has been received without any problem, and the process of the response detection means 102 ends. (Figure 10: S
302 NO → end). If a response is received, the control means 105 carries out the subsequent communication processes.

Subsequently, when the response detecting means 102 detects a "collision", the response invalidating means 103 constituting the reader / writer 901 is, for example, the response invalidating means 10.
Set "1" to the counter provided in 3 (Fig. 1
0: S302 YES → S303).

Next, when the response invalidating means 103 sets "1" in the counter, subsequently, the predetermined storage means corresponding to the time slot N (N is the value of the counter) indicated by the counter is referred to, It is determined whether "normal response" is stored.

Here, the time slot 1 (110
Since a normal response is not recorded in the storage means corresponding to 2), it is then confirmed whether the number of time slots transmitted by the initial response request matches the value of the counter (FIG. 10: S304 NO). → S306).

Here, since the number of time slots is "1", the slot number increasing means 603 uses the second identification processing 1
The value of the number of time slots set in the initial response request 1102 transmitted at 108 is increased (FIG. 10: S
306 YES → S704). Here, it is assumed that the number of time slots is set to "4".

Then, the initial response request 1112 is made.
Is transmitted, each non-contact IC card 410-440
Selects one from the set four time slots. Here, for example, the non-contact IC cards 410, 430
Selects Timeslot 2 (1110) and contacts I
The C card 420 selects the time slot 1 (1109), and the contactless IC card 440 selects the time slot 3 (1109).
111) is selected.

In this case, the response detecting means 102 sends the response 1114 of the contactless IC card 420 to the response of the time slot 1 (1109) and the response to the time slot 2 (111).
0) response to the contactless IC card 410 response 1113
"Collision" with the response 1115 of the contact IC card 430
In response to time slot 3 (1111)
The response 1116 of the C card 440 is detected.

The response detecting means 102 causes the "collision" to occur.
Since the response invalidating means 103 has detected
By repeating the processing S303 to S366 in 0,
A response invalidation command 1117 is transmitted to the non-contact IC card 420, and a response invalidation command 1118 is transmitted to the non-contact IC card 440.

As a result, the above-mentioned non-contact IC card 4 is
20 and the contactless IC card 440 shift to the active period, that is, do not respond to the subsequent initial response request.

Subsequently, the counter N is compared with the time slot number, and when the processing for all four time slots is completed, the slot number increasing means 603 performs the time slot number increasing processing in the third identification processing 1201. (FIG. 10: S306 YES → S704).

Here, the slot number increasing means 603 is used.
May increase the number of time slots, but in this case, the slot number increasing means 603 receives the fact that the response invalidation processing has been performed from the invalidating means 103, and the slot number increasing means 603 causes the time slot number to increase. Does not increase the number of slots.

As described above, by determining the increase in the number of time slots based on the presence / absence of the response invalidation process, it is not necessary to increase the unnecessary time slot, that is, the identification is made by the increase in the number of time slots. Processing delay can be prevented.

Then, the control means 105 causes the initial response request 1205 for the third identification processing 1201.
Is transmitted (FIG. 10: S301). The number of time slots in the initial response request 1205 is “4”.

In the identification processing 1201 for the third time,
The non-contact IC card 410 has a time slot 2 (1
203) is selected, and the non-contact IC card 430 is assumed to be the time slot 4 (1204). As described above, the non-contact IC cards 420 and 440 do not respond to the initial response request because the non-contact IC cards 420 and 440 have already entered the active period by the response invalidation processing.

In the third identification processing 1201, the response detecting means 102 does not detect a "collision" and detects a "normal response". Therefore, the non-contact IC
The cards 410 and 430 are identified by the reader / writer 901 through normal (conventional) processing (FIG. 10: S302 → end).

After that, each non-contact IC card 410 to 440
Performs a predetermined communication with the reader / writer 901, and ends the communication by, for example, a "HALT" command or the like.

In the following (next) identification processing 1208,
Since the identification process is repeated from the process S701 again, the number of time slots set in the initial response request 1210 is "1".

Further, the non-contact IC cards 420 and 440 whose responses have been invalidated can also respond to the initial response request (the active period has ended) by the “HALT” command at the end of communication.

As described above, the IC card corresponding to the response that has not caused a collision performs the response invalidation process each time, so that the identification process is performed only on the IC card having the collision, and the time is appropriately set. By increasing the number of slots, even in a system that requires identification of a large number of IC cards, identification according to the number of IC cards can be performed flexibly and efficiently.

As in the first and second embodiments, the present invention may be applied to a reader / writer using a contact type IC card instead of the non-contact type IC card. Also,
It may be applied to a reader / writer using a slot marker method instead of the time slot method, or may be applied to a reader / writer using another slot method.

The increase in the number of time slots may be a fixed value or a variable value.

Further, in a reader / writer which is expected to communicate with a plurality of IC cards from the beginning, it is not always necessary to set “1” to the number of time slots of the first initial response request, and the time corresponding to the reader / writer is required. The number of slots may be set.

(Fourth Embodiment) Next, FIGS.
Referring to, the reader / writer 1 according to the fourth embodiment of the present invention
301 will be described.

The reader / writer 1301 shown in FIG.
It has the same configuration as the reader / writer 101 in the first embodiment, but instead of the response detection unit 102 and the response invalidation unit 103, a storage unit 1302 and a calculation unit 1303.
And slot number resetting means 1303. The details of each means will be described later. 14 is an image diagram of data stored in the storage unit 1302, and FIG. 15 is a flowchart of processing executed by the reader / writer 1301 according to the fourth embodiment.

As described in the first to third embodiments, the control means 105 transmits the initial response request to, for example, a plurality of non-contact IC cards, so that each of the plurality of non-contact IC cards can be transmitted. The points of recognition are the same.

Here, when the recognition is completed normally, the storage means 1302 stores the number of normally-contacted non-contact IC cards. For example, as a storage method, as shown in FIG. 14A, 10 storage areas are provided here, and the recognized numbers are sequentially stored from the newest storage areas 1401 to 1401.
Remember in 10. By doing so, the number of recently recognized non-contact IC cards can be stored. Next, when the storage in the storage unit 1302 is completed, the calculation unit 1303 determines the number of time slots to be included in the initial response request to be transmitted next time, based on the stored number of the 10 non-contact IC cards. It is calculated. Here, any method may be used to calculate the number of slots, but for example, the average value of the past ten times may be used. In this case, for example, round up
Or you can round it down. Specifically, in the example shown in FIG. 14A, the average of the numerical values (the number of sheets) stored in each of the storage areas 1401 to 1410 is “1.2”, and the number of time slots included in the initial response request is “1”. It becomes (adopts the truncation). On the other hand, FIG. 14B shows an example of the case where non-contact IC cards have spread and the number of non-contact IC cards in wallets has increased. In this case, the number of sheets recognized at one time is increasing, and each storage area 1 shown in FIG.
The average of the numerical values (the number of sheets) stored in 411 to 1420 is
It becomes "5.1", and the number of time slots included in the initial response request becomes "5" (truncation is adopted).

The time slot number calculated by the calculating means 1303 is notified to the slot number resetting means 1304, and the slot number resetting means 1304 notifies the time slot number included in the subsequent initial response request. The numerical value set is set.

Thereafter, the control means 105 is reset by the slot number resetting means 1304 (see FIG. 14).
In the case of B, "5") is used to send the initial response request. When the number of time slots is recalculated on the contactless IC card side using the value included in the initial response request, the value calculated on the contactless IC card side should be “5” or more. Then, "3" is stored in the initial response request.

As described above, by dynamically changing the number of time slots based on the past history of recognizing a non-contact IC card, it is possible to shorten the identification processing time of each card with a high probability. Become. In addition, even if the number of non-contact IC cards owned by one user increases (changes) over time, the system using the reader / writer automatically changes the initial value of the time slot. ,
As a result, the service life of the system can be extended.

Next, a method of calculating different numbers of time slots by the calculating means 1303 will be described with reference to FIG.

In the method described below, the calculating means 1303 changes the initial value by paying attention to the continuity of the recognized number of sheets.

First, it is assumed that the control means 105 completes the identification process by setting the initial value (the number of time slots) included in the initial response request to N (FIG. 15: S150).
1). Then, the storage unit 1302 stores the recognized number n1 in the storage area 1421 and also copies the number of sheets recognized in the previous processing stored in the storage area 1421 to the storage area 1422 to obtain the number n2. To do.

Next, the calculating means 1303 acquires the numbers n1 and n2 from the storage means 1302 and compares whether the two numbers are the same (FIG. 15: S1502 →).
S1503).

If n1 and n2 are not the same, the continuous counter nc is set to "0" (FIG. 15: S15).
03 NO → S1504). Here, the continuous counter nc is a value indicating how many times the same number of cards have been recognized in succession.

Further, the calculation means 1303 adds "1" to the card search count Ns, and further, the history count Nsum.
Is added to n (FIG. 15: S1505 → S150)
6). Here, the card search count Ns indicates the number of times the reader / writer has normally completed the identification processing of the non-contact IC card so far, and the history count Nsum is the non-contact IC recognized by the reader / writer so far. Indicates the number of cards.

Subsequently, the calculating means 1303 substitutes the numerical value calculated by "Nsum ÷ Ns × 1.5" (rounded up after the decimal point) for the initial value N (FIG. 15: S150).
7). Here, “Nsum ÷ Ns” indicates the average value of the number of cards recognized in the identification process per time until now. The initial value larger than the number of cards is calculated by multiplying the “Nsum ÷ Ns” by “1.5”, but the “1.5” may be another numerical value.

The initial value N calculated by the calculating means 1303 is notified to the slot number resetting means 1304, and the slot number resetting means 1304 sets the notified value to the initial value N. The initial value N is used in the subsequent initial response request (identification process) by the control means 105.

Now, in the above comparison processing: S1503, if the above n1 and n2 are the same, the continuous counter nc is incremented by "1", and the threshold value Nx and the continuous counter Nc are increased.
(FIG. 15: S1503 YES → S1508)
→ S1509).

Here, when the continuous counter nc <= Nx, the initial value N is determined by the processes S1505 to S1507 (FIG. 15: S1509 NO → S15) as in the above.
05 ... S1507).

On the other hand, when the continuous counter nc> Nx, the card search count Ns is initialized to "0" and the history count Nsum is also initialized to "0" (FIG. 15: S).
1509 YES → S1510 → S1511). continue,
The calculation means 1303 determines whether n1 is “1” (FIG. 15: S1512).

Here, when n1 is "1", the initial value N is set to "1", and the initial value N is used in the subsequent initial response request (identification processing) by the control means 105 (Fig. 15: S1512 YES → S1513).

When n1 is not "1", the numerical value calculated by "n1 × 1.5" (rounded up to the right of the decimal point) is substituted for the initial value N, and the initial value N is set to the above control means. It is used in the subsequent initial response request (identification processing) by 105 (FIG. 15: S1512 NO → S151).
4). Here, the numerical value "1.5" is a value for calculating an initial value larger than the number of cards, as in the above.
The “1.5” may be another numerical value.

As described above, the threshold value (Nx) may be used to determine the number of consecutive times of the number of recognized cards, and the initial value may be calculated based on the number of consecutive times. In the above process, when the number of recognized sheets is "1", the process of multiplying by "1.5" and rounding up is not performed. This is because when the number of cards is one, the identification processing can be ended most quickly by setting the initial value to "1".

The storage means, calculation means and slot number resetting means in the fourth embodiment are the same as those in the first to third embodiments.
It is possible to implement in addition to 3. By carrying out at the same time, it becomes possible to further shorten the identification processing time.

[0137]

As described above, when the normal response is received, the response invalidation command is transmitted to the IC card which has transmitted the normal response even if the collision is detected. Subsequent identification processing applies only to the IC card that has sent the response that caused the collision. That is, in the subsequent identification processing, the probability of collision of responses is reduced, that is, the identification processing can be completed at high speed.

Further, since the presence / absence of a collision in the response from the IC card is detected and the time slot is increased based on the presence / absence of the collision only, the number of IC cards can be adjusted without adding a complicated structure to the reader / writer. Accordingly, the identification can be efficiently performed.

Further, the IC card corresponding to the response that has not caused the collision performs the response invalidation process each time, so that the identification process is performed only for the IC card having the collision, and the time slot number is appropriately set. By increasing the number, even in a system that requires identification of a large number of IC cards, identification can be flexibly and efficiently performed according to the number of IC cards.

Further, by dynamically changing the number of time slots based on the past history of recognizing the non-contact IC card, it becomes possible to shorten the identification processing time of each card with high probability. At the same time, it becomes possible to extend the service life of the system using the reader / writer.

[Brief description of drawings]

FIG. 1 is a functional block diagram of a reader / writer according to a first embodiment.

FIG. 2 is a hardware configuration diagram of a reader / writer according to the first embodiment.

FIG. 3 is a flowchart of processing executed by a reader / writer according to the first embodiment.

FIG. 4 is an image diagram of identification processing according to the first embodiment.

FIG. 5 is a communication image diagram of a reader / writer and a non-contact IC card.

FIG. 6 is a functional block diagram of a reader / writer according to the second embodiment.

FIG. 7 is a flowchart of processing executed by a reader / writer according to the second embodiment.

FIG. 8 is an image diagram of identification processing according to the second embodiment.

FIG. 9 is a functional block diagram of a reader / writer according to a third embodiment.

FIG. 10 is a flowchart of processing executed by the reader / writer according to the third embodiment.

FIG. 11 is a first image diagram of identification processing according to the third embodiment.

FIG. 12 is a second image diagram of the identification processing according to the third embodiment.

FIG. 13 is a functional block diagram of a reader / writer according to the fourth embodiment.

FIG. 14 is an image diagram of data stored in a storage unit.

FIG. 15 is a flowchart of processing executed by the reader / writer according to the fourth embodiment.

FIG. 16 is a communication image diagram of a conventional reader / writer and a non-contact IC card.

FIG. 17 is an image diagram of conventional identification processing.

FIG. 18 is a diagram showing a format of an initial response request packet.

[Explanation of symbols]

101 reader / writer 102 Response detection means 103 Response invalidation means 104 ROM 105 control means 106 transmitting / receiving means 107 antenna means

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Shinji Kawano             3-10-18 Kagamiyama, Higashihiroshima-shi Matsu Co., Ltd.             Shimoden Information System Hiroshima Laboratory (72) Inventor Hideo Ozeki             3-10-18 Kagamiyama, Higashihiroshima-shi Matsu Co., Ltd.             Shimoden Information System Hiroshima Laboratory (72) Inventor Hiromi Ehara             3-10-18 Kagamiyama, Higashihiroshima-shi Matsu Co., Ltd.             Shimoden Information System Hiroshima Laboratory F-term (reference) 2C005 MA25 MA27 SA26 SA30 TA22                 5B058 CA15 CA17 CA23 KA01 KA04                 5K012 AB05 AB12 AB18 AC01 AC08                       AC10 BA03

Claims (17)

[Claims] 1. In an IC card reader / writer that communicates with a plurality of IC cards, a response detection unit that detects a normal response from the IC card to a request for identifying each IC card and a collision of the responses, When the response detecting means receives a normal response from the IC card, even if the collision is detected, the IC card which has transmitted the normal response does not respond to the subsequent request. A reader / writer, comprising: a response invalidating unit that transmits a response invalidating command that is an instruction. 2. The reader / writer according to claim 1, wherein a time slot is used to identify the IC card. 3. The reader / writer according to claim 2, further comprising slot number increasing means for increasing the number of time slots based on only the presence or absence of the collision detected by the response detecting means. 4. The reader / writer according to claim 3, wherein the slot number increasing means increases the number of time slots based on whether or not the response invalidating command transmits the response invalidating command. 5. A storage means for storing the number of the IC cards normally recognized, and the number of IC cards stored in the storage means,
A calculating means for calculating the number of time slots included in the first request for identifying each IC card, and a slot number re-setting for setting the number of time slots calculated by the calculating means as the number of time slots for the first request. The reader / writer according to claim 2, further comprising setting means. 6. The response invalidation command is ISO / I
EC (International Organization For Standardizatio)
n / International Electrotechnical Commission) 14
443 based "ATTRIB" command, or "HA"
The reader / writer according to claim 1, which is an LT "command. 7. An IC card reader / writer that communicates with a plurality of IC cards using one or more time slots, and collision detection for detecting a collision of responses from the IC cards to a request for identifying each IC card. A reader / writer comprising: means and slot number increasing means for increasing the number of time slots based only on the presence or absence of the collision detected by the collision detecting means. 8. The reader / writer according to claim 7, wherein the number of time slots included in the first request is “1”. 9. Further, based on the storage means for storing the number of normally recognized IC cards, and the number of IC cards stored in the storage means,
Calculating means for calculating the number of time slots included in the first request for identifying each IC card, and resetting the number of slots for setting the number of time slots calculated by the calculating means as the number of slots at the first request The reader / writer according to claim 7, further comprising: 10. In an IC card reader / writer that communicates with a plurality of IC cards using one or more time slots, a storage unit that stores the number of the IC cards that are normally recognized, and the storage unit stores the number. Based on the number of IC cards
Calculating means for calculating the number of time slots included in the first request for identifying each IC card, and resetting the number of slots for setting the number of time slots calculated by the calculating means as the number of slots at the first request A reader / writer provided with a means. 11. The storage means stores a predetermined number of times of the I.
The reader / writer according to claim 10, which stores the number of C cards. 12. A method for identifying a plurality of IC cards in a communicable manner, the detecting step of detecting a normal response from the IC card to a request for identifying each IC card and a collision of the responses, When a normal response is received from the IC card, the normal response is transmitted even if the collision is detected.
And a response invalidation step of transmitting a response invalidation command, which is a command not to respond to the subsequent request, to the C card. 13. An identification method for communicatively identifying a plurality of IC cards, a collision detection step of detecting a collision of responses from the IC cards to a request for identifying each IC card, And a slot number increasing step for increasing the number of the time slots used for the identification based only on the presence or absence of the identification method. 14. A method for identifying a plurality of IC cards in a communicable manner, wherein the storing step stores the number of the IC cards when the plurality of IC cards are normally recognized, and the storing step stores the number of the IC cards. The calculation step of calculating the number of time slots to be included in the first request for identifying each IC card based on the number of the generated IC cards, and the time slot number calculated in the calculation step are calculated at the time of the first request. And a step of resetting the number of slots to be set as the number of slots. 15. A computer for communicatively identifying a plurality of IC cards, a detection step of detecting a normal response from the IC card to a request for identifying each IC card and a collision of the responses, and the IC. When a normal response is received from the card, the normal response is sent even if the collision is detected.
A program for executing a response invalidation step of transmitting a response invalidation command which is an instruction not to respond to the subsequent request to the C card. 16. A collision detecting step of detecting a collision of a response from the IC card to a request for identifying each IC card to a computer capable of communicating with a plurality of IC cards, and the presence or absence of the detected collision. A slot number increasing step for increasing the number of time slots used for the identification based on only the above. 17. A storage step of storing the number of the IC cards when the plurality of IC cards are normally recognized in a computer for communicatively identifying the plurality of IC cards, and the storing step. A calculation step for calculating the number of time slots to be included in the first request for identifying each IC card based on the number of IC cards, and the time slot number calculated in the calculation step for the slot at the time of the first request. A program for executing the step of resetting the number of slots set as a number.