JP2006113737A - Communication system and communication method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a communication system which is composed of a reader/writer and a variety of contactless data carriers, and identifies the individual data carriers in a short communication period. <P>SOLUTION: Information unique to a data carrier such as a usage and a user is classified in a layered manner to the minimum necessary scope that the data carrier can distinguish each other, the classification information is assigned to the information blocks having a corresponding layered structure, and composes an identification code by the total information of these information blocks. The recognition action is initiated from an information block that carries out an uppermost broad classification, and if a collision error occurs in an arbitrary layer, the recognition action is moved on to a next lower layer. Furthermore, in an arbitrary layer other than the uppermost layer, when all values which can be taken in the information block of the layer have been taken, the recognition action is moved on to a next upper layer. When all the values which can be taken in the information block of the uppermost layer are taken, the recognition action is terminated. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an information communication system and a communication method, and more particularly to an improvement of a communication system including a contactless data carrier such as a contactless IC card and a reader / writer that performs wireless communication with the data carrier. Is.

  The recognition operation in the conventional communication system described above, that is, the operation in which the reader / writer recognizes the identification codes of all the data carriers with respect to one or more non-contact data carriers existing in the communication area is disclosed in Patent Document 1, for example. It is specified.

In the conventional communication system shown in the above document, the reader / writer uses the hierarchical structure random code recorded on the data carrier, specifies the hierarchy and random code from the reader / writer, and queries the data carrier, For the data carrier in which the inquiry information and the random code recorded in the designated hierarchy match, a response to notify the match is requested.
JP 2000-131423 (pages 4 to 11, FIGS. 2 and 8)

However, in the conventional communication system,
First, since it is necessary to record a random code having a hierarchical structure different from the identification code on the data carrier, the amount of recording information necessary for recognition increases, and the reader / writer randomly selects the identification. Since there are two steps, a process of issuing a code and recognizing the difference in the data carrier, and a process of checking the identification code of the data carrier in which the reader / writer has recognized the difference, there is a disadvantage that the recognition time becomes long,
Second, as the amount of data carriers issued increases, there is a high possibility that there will be a plurality of data carriers in which all random codes match, and if there are a plurality of data carriers in the communication area of one reader / writer, There is a drawback that there is a high possibility that communication between the carrier and the reader / writer becomes impossible,
Thirdly, due to the nature of the random code, the random code cannot be assigned by meaning the data carrier specific information such as the use of the data carrier and the user. Since only the identification code can be assigned the unique information, there is a disadvantage that there is a limit to the expansion of the use of the data carrier, the user, etc. when the information amount of the identification code is fixed.

  The present invention has been made to solve the above-described conventional problems, and a collision error occurs when a plurality of data carriers having the same identification code are simultaneously present in the communication area of one reader / writer. An object of the present invention is to provide a communication system capable of recognizing individual data carriers with a minimum necessary communication amount and time, and a communication method used in the communication system.

  In order to solve the above-mentioned problems, the present invention hierarchically classifies data carrier specific information such as the use of a data carrier and a user to the minimum necessary range in which the data carriers can distinguish from each other. Classification information is assigned to an information block having a hierarchical structure corresponding to the structure, and an identification code is constituted by comprehensive information of these information blocks.

  Then, the recognition operation is started from the information block that performs the broad classification, and if a collision error occurs in any layer, the recognition operation is performed by moving to a lower layer, and any that is not the highest layer If all the values that can be obtained in the information block of that hierarchy are completed, the recognition operation is continued by moving to the upper hierarchy, and if all values that can be obtained in the information block of the highest hierarchy are completed. This is done by terminating the recognition operation.

  That is, the communication system according to claim 1 of the present invention includes a plurality of data carriers that are carriers for holding data, and a reader / writer that reads and writes data held in the plurality of data carriers, A reader / writer communicates with each of the plurality of data carriers, and each of the plurality of data carriers includes a first layer to an Nth layer (N is a number for identifying the plurality of data carriers from each other). An identification information storage unit composed of N blocks each holding unique identification information having a hierarchical structure up to (integer of 2 or more), information designated by an instruction signal from the reader / writer, and the identification information storage unit An operation unit that performs a comparison operation on information, and a reply unit that performs a response response according to a result of the comparison operation, wherein the reader / writer A transmission unit that transmits the instruction signal including information for identifying a number of data carriers, and a reception unit that receives response responses from the plurality of data carriers, and the transmission unit of the reader / writer includes the plurality of data carriers. For the data carrier, the instruction signal including the information of the layer value k (k is an integer satisfying 1 ≦ k ≦ N) and the comparison information corresponding to the kth block is transmitted, and the plurality of data carriers are transmitted. Each calculation unit compares the received comparison information corresponding to the k-th block from the reader / writer with the information actually recorded in each k-th block, and among the plurality of data carriers, The reply section of the data carrier in which the two pieces of information match each other returns a response notifying the reader / writer that the two pieces of information match.

  Further, in the communication system according to claim 2 of the present invention, in the communication system according to claim 1, when the reader / writer does not send back the response as a result of performing the transmission, the reader / writer returns to the k-th block. If the corresponding comparison information is changed and the response is returned from only one data carrier, the comparison information corresponding to the k-th block is similarly changed after the necessary communication with the data carrier is completed. When the response is returned from a plurality of data carriers, the hierarchy value k is increased, and the corresponding comparison information is changed to comparison information corresponding to the block corresponding to the increased hierarchy value k. After the change, the instruction signal is transmitted again.

The communication system according to claim 3 of the present invention is the communication system according to claim 1, wherein the reader / writer does not send back the response as a result of the transmission by the reader / writer, and the reader / writer Has transmitted all the corresponding values that the k-th block can take to the plurality of data carriers, and the reader / writer has started communication with the plurality of data carriers at the first layer value. When k ₀ is smaller than k, the reader / writer resets the value of k to the previous value that changes to the current value, and resets the corresponding comparison information. The instruction signal is transmitted again after changing to comparison information corresponding to the block corresponding to k.

The communication system according to claim 4 of the present invention is the communication system according to claim 1, wherein the reader / writer does not send back the response as a result of the transmission by the reader / writer, and the reader / writer Has transmitted all the corresponding values that the k-th block can take to the plurality of data carriers, and the reader / writer has started communication with the plurality of data carriers at the first layer value. is k ₀ is, if equal to the k, the reader-writer is characterized in that to terminate the communication.

  The communication system according to claim 5 of the present invention is the communication system according to claim 1, wherein the comparison information corresponds to the k-th block, as well as the first to k-1 blocks. All or part of the information is included.

  In the communication system according to claim 6 of the present invention, in the communication system according to claim 2, the reader / writer increases the hierarchical value k to the required hierarchical value k. The comparison information corresponding to the corresponding block is changed and the instruction signal is transmitted until the one data carrier is specified, which is repeated.

  According to a seventh aspect of the present invention, there is provided a communication method in which communication is performed between a first communication device and a plurality of second communication devices, each of the plurality of second communication devices. Stores identification information composed of N blocks each holding unique identification information from the first layer to the Nth layer that are hierarchized for identifying the plurality of second communication devices from each other. The first communication device transmits an instruction signal including information on the layer value k and comparison information corresponding to the k-th block to the plurality of second communication devices, and the second communication device The second communication device in which the information included in the received instruction signal from the first communication device is compared with the identification information recorded in each second communication device, and the two information matches. Is a response that informs the first communication device that a match has occurred. The first communication device receives a response from the second communication device and starts a recognition operation for identifying each of the plurality of second communication devices from the highest layer. When a collision error in which two or more of the second communication devices send back responses occurs in any layer, the recognition operation is performed by moving to a layer one level lower than the layer and performing a recognition operation. The two communication devices are individually identified.

  In the communication method according to claim 8 of the present invention, in the communication system according to claim 7, when the collision error occurs, the first communication device causes the collision error in the hierarchy to occur. It moves to the hierarchy one level lower than the position.

  The communication method according to claim 9 of the present invention is the communication system according to claim 7, wherein the first communication device is capable of taking all the correspondences that can be taken in an arbitrary hierarchy that is not the highest hierarchy. When the comparison information to be acquired is completed, the recognition operation is continued by moving from the hierarchy to the corresponding higher hierarchy, and the recognition operation is performed when all the comparison information that can be acquired at the highest hierarchy is acquired. It is characterized by terminating.

  According to the communication system and the communication method of the present invention, the data carrier existing in the communication area of the reader / writer is recognized by the presence of a plurality of data carriers whose identification codes are stochastically matched as in the conventional communication system. This can be realized by communication with the minimum amount of information necessary for recognizing the difference between the data carriers without causing the problem of communication inability.

  Furthermore, the identification code does not need to have a fixed length, and even if the hierarchical structure of the identification code is changed later, the change information can be easily updated and recorded in the reader / writer to record the use of the data carrier, the user, etc. Can be expanded.

(Embodiment 1)
Hereinafter, a communication system and a communication method according to Embodiment 1 of the present invention will be described with reference to FIG. 1, FIG. 2, and FIG.

  FIG. 1 is a diagram showing a schematic configuration of a communication system according to the first embodiment. In FIG. 1, the communication system according to the first embodiment includes a reader / writer (first communication device) 1 and one or a plurality of data carriers (second communication devices) 2. Wireless communication by electromagnetic inductive coupling is performed with the data carrier 2.

  The reader / writer 1 includes at least a transmission unit 11 that transmits an instruction signal for identifying and controlling the data carrier 2, a reception unit 12 that receives a reply response from the data carrier 2, and a plurality of data carriers 2. A memory 13 for holding identification information and the like, and a control unit 14 for performing integrated control of the above-described units are provided.

  The data carrier 2 has at least recording blocks independent of each other from the first block to the Nth block for recording information in units of blocks as information recording means in the data carrier 2. An identification information storage unit 23 for recording information individually (here, an integer of N ≧ 2), a reception unit 22 for receiving an instruction signal from the reader / writer 1, comparison information in the received instruction signal, A calculation unit 24 that compares the information held in the identification information storage unit 23 and a transmission unit 21 that returns a response informing the reader / writer 1 that the two information match when the two information match.

Next, the configuration of the identification code of the data carrier 2 will be described with reference to FIG.
FIG. 2 is a diagram showing the configuration of the identification code of the data carrier 2 in the communication system according to the first embodiment.

  The identification code of the data carrier 2 is composed of N information blocks of a first block, a second block,. Each of the N information blocks having a hierarchical structure corresponds to one hierarchy of identification information. That is, the information that roughly classifies the data carrier at the highest level is the first block, the information that further subclassifies the information corresponding to the information of the first block is the second block, and so on. Corresponding to the information of one block, information for further subclassifying the information of the (N-1) th block is recorded in the Nth block.

  The recognition of the data carrier 2 is reduced to a necessary minimum hierarchy in which the reader / writer 1 can recognize the difference in the identification codes of each of the data carrier 2 existing in the communication area, and the data of these information blocks is transferred. This is done by comprehensive acquisition.

  Next, the communication method according to the first embodiment will be described with details of the recognition operation for recognizing the data carrier.

In the communication system according to the first embodiment, the transmission unit 11 of the reader / writer 1 includes, for a plurality of data carriers 2, an instruction signal including information on the layer value k and comparison information corresponding to the kth block. Send. That is, the transmission unit 11 of the reader / writer 1 performs information on the layer value k and the first block, the second block,..., The k-th block (k is 1 ≦ k ≦ N) for a plurality of data carriers 2. Data for comparison corresponding to the information block of the (integer integer) is shown, and further, a response is sent to the data carrier 2 having an identification code that matches these comparison data in all layers to notify that they match. A command REQ _k which is an instruction signal is transmitted.

In the data carrier 2, the receiving unit 22 receives the command REQ _k , and the calculation unit 24 holds the comparison data of the kth block included in the command REQ _k and the identification information storage unit 23. To the identification information of the kth block. As a result of the comparison, if the comparison data of the kth block matches the identification information of the kth block held in the identification information storage unit 23, that is, if the results up to the (k-1) th hierarchy are included, the first hierarchy The data carrier 2 determined that the comparison data from the first layer to the k-th layer and the stored identification information from the first layer to the k-th layer all match is transmitted by the transmitting unit 21 to the REQ _k . A response ANS_REQ _k is returned to the reader / writer 1.

The REQ _k command includes general data {k, D ₁ , D ₂ ,..., D _k }, which is a collection of comparison data up to the first block, the second block,. The k value of the REQ command, that is, the depth of the hierarchy is indefinite. The smaller the k value, that is, the shallower the hierarchy, the shorter the data length of REQ _k . Conversely, the larger the k value, that is, the deeper the hierarchy, the longer the data value of REQ _k . Here, D ₁ , D ₂ ,..., D _k are data recorded in the first block, the second block,.

Next, the recognition algorithm will be described with reference to FIG.
FIG. 3 is a flowchart showing a recognition algorithm in the communication system according to the first embodiment.

The reader / writer 1 is set to k = 1 in the initial setting before the start of communication, so that the transmission unit 11 first transmits a REQ ₁ command indicating comparison data of the first block which is the first layer. (Step S200).

The following recognition algorithm will be described with reference to the processing flow of the reader / writer 1 for a general REQ _k command issuance, assuming that k = 1 and not 1 and 1 <k ≦ N.

The reader / writer 1 changes the _Dk value that can be taken at the current position in the hierarchical structure, that is, the k value and the current position set by the data of all higher layers, in any k-th block hierarchy. In other words, REQ _k is issued while changing the D _k value so as to take all the classification items assigned to the current position (steps S202 and S203).

The control unit 14 of the reader / writer 1 makes the following three determinations after issuing each REQ _k command.

That is, as a result of the reader / writer 1 specifying the total data {k, D ₁ , D ₂ ,..., D _k } and transmitting REQ _k by the transmission unit 11,
As a first result, when the receiving unit 12 of the reader / writer 1 does not receive any reply, the control unit 14 of the reader / writer 1 stores general data {k, D ₁ , D _{2 ,.} }, It is determined that there is no data carrier 2 having an identification code that matches,
As a second result, when the receiving unit 12 of the reader / writer 1 receives a reply that can be determined to be ANS_REQ _k, that is, ANS_REQ from a plurality of data carriers 2 having the same identification code as the total data indicated by REQ _k. When it can be determined that there is no collision of return signals generated when _k is returned, the control unit 14 of the reader / writer 1 stores the total data {k, D ₁ , D ₂ ,..., D _k } in the communication area. It is determined that there is only one data carrier 2 having an identification code that matches
As a third result, when the receiving unit 12 of the reader / writer 1 receives a reply that cannot be determined as ANS_REQ _k, that is, from a plurality of data carriers 2 having the same identification code as the total data indicated by REQ _k , ANS_REQ _k Are simultaneously returned, it can be determined that a collision of reply signals has occurred, and the control unit 14 of the reader / writer 1 matches the total data {k, D ₁ , D ₂ ,..., D _k } in the communication area. It is determined that there are a plurality of data carriers 2 having identification codes.

  Next, the control unit 14 of the reader / writer 1 executes the following processing for the above three determinations.

  First, for the first result determination, the reader / writer 1 performs a comprehensive data change process, which will be described later, and continues to recognize (step S217).

Next, for the second result determination, the reader / writer 1 designates the total data {k, D ₁ , D ₂ ,..., D _k } for the data carrier 2 that can recognize the identification code. Then, the transmission unit 11 issues a SEL _k command for transitioning the data carrier to a normal communication enable state in which normal communication is possible (step S207).

The data carrier 2 that has received the SEL _k command by the receiving unit 22 transitions to the normal communication enabled state (step S208).

  The reader / writer 1 and the data carrier 2 perform necessary communication in this state (step S209).

Unless the data carrier 2 that is already in the normal communication enabled state can be identified with the comprehensive data {k, D ₁ , D ₂ ,..., D _k }, the necessary communication is performed until the data carrier 2 can be identified. , Including repeating the recognition operation while changing the comparison information down the hierarchy (see the example of steps S5 and S6 in FIG. 5).

When the necessary communication is completed, the reader / writer 1 designates the total data {k, D ₁ , D ₂ ,..., D _k } for the data carrier 2, except for the WAKE UP _k command described later. The transmitter 11 issues a HALT _k command for transitioning to a non-response state (step S210).

The data carrier 2 that has completed the necessary communication with the reader / writer 1 does not respond to anything other than the WAKE UP _k command in response to the HALT _k command, that is, excluded from the recognition target from the reader / writer 1 in the subsequent recognition operation. (Step S211).

Here, the WAKE UP _k command indicates that the reader / writer 1 receives the HALT _k and does not respond to the data carrier 2 other than the WAKE UP _k command, so that the total data {k, D ₁ , D _{2 ,.} } To change to a state in which REQ _k , SEL _k , and HALT _k are accepted again.

  After the processing of the above contents, the reader / writer 1 performs a comprehensive data changing process described later and continues to recognize (step S217).

  As described above, the reader / writer 1 repeats the recognition operation while reducing the number of data carriers 2 to be communicated one by one through the above-described series of processes, and finally ends communication with all the data carriers 2 existing in the communication area. Will do.

Finally, for the third result determination, the reader / writer 1 further increases the value of k in order to recognize the difference in the identification codes of the plurality of data carriers 2 that have collided, that is, the current total data _{{k, D 1, D 2} , ..., D k} with respect REQ _k command that specifies, one step lower data block, {D _1, D _2, ..., D _k} value corresponding to D A REQ _{k + 1} command designating the total data {k + 1, D ₁ , D ₂ ,..., D _k , D _{k + 1} } while changing _{k + 1} is issued by the transmitter 11 to continue the recognition operation ( Steps S212 and S213).

Next, a process for changing the above-described general data {k, D ₁ , D ₂ ,..., D _k } will be described.
There are two cases for the change processing of the comprehensive data {k, D ₁ , D ₂ ,..., D _k }.

As a first case, if there is another possible D _k value corresponding to {D ₁ , D ₂ ,..., D _k−1 } in the k th block that is the current block, the possible D _k If the value is one, the D _k value is changed to this value, and if there are a plurality of values, the D _k value is changed to any value (step S202), and then REQ _k is issued again to continue the recognition operation. (Step S203).

As a second case, when there are no other possible D _k values corresponding to {D ₁ , D ₂ ,..., D _k-1 }, all possible D _k values, ie the current Since the issuance of the REQ _k command has been completed for all the minor classifications that can be taken in the k-th block, thereafter, k ≠ 1, that is, if it is not the highest block, the value of k is decremented by 1 and the layer one higher Returning to the (k-1) th block (step S216), if k = 1, that is, the highest block, the recognition operation is terminated (step S215).

At this time, when returning from the k-th block to the (k-1) -th block which is one higher level, there is another _Dk-1 value that can be further corresponding to this (k-1) -th block. In the same manner, the D _k-1 value is changed (step S217), and REQ _k-1 is issued. If there is no other corresponding D _k-1 value, the (k− 1) If the block is not the most significant block, the value of k is decremented by 1 and the processing continues with the (k-2) th higher block, and if the (k-1) th block is the most significant block, it is recognized. The operation is finished (steps S214 and S215).

In this way, starting from the REQ command having the shortest data length including the information of the first layer, the layer is deepened as necessary, and the REQ command having a long data length including the information of the plurality of layers is issued for recognition. Through the above series of operations, the reader / writer can recognize the difference in the identification codes of all data carriers existing in the communication area by issuing the REQ _k command with the minimum required data length, and the recognition time is minimized. An integrated communication system can be realized.

  In addition, since a unique value is assigned to each data carrier identification code, a recognition error occurs due to the presence of multiple data carriers having the same identification code in the communication area of the reader / writer. There is no fear of doing.

In the series of operations described above, the total data {k, D ₁ , D ₂ ,..., D _k } is included in the REQ _k command. If the upper layer can be recognized, that is, if the k value and the values D ₁ , D ₂ ,..., D _k−1 can be recognized, the data included in REQ _k is only D _k and the data of REQ _k is further _obtained . It may be a system for shortening the length.

Next, a more specific embodiment of the present invention will be described with reference to FIG.
FIG. 4 is a diagram illustrating the specification of the identification code of the data carrier in the communication system according to the first embodiment. Here, various data cards are assumed as the data carrier, but the present invention is not necessarily limited to this.

In the specification of this identification code, the value of the first block indicates the card classification as the highest classification. In this embodiment, the value D ₁ of the first block is defined as 1 for a bank card, 2 for a credit card, and 3 for a commuter pass card.

The second block shows the lower (second hierarchy) classification. For example, if the card to be identified is a bank card, it indicates the name of the financial institution, and the value (D ₁ , D ₂ ) composed of the value of the first block and the value of the second block is (1, 1). Bank A and (1,2) Bank B. If the card to be identified is a commuter pass, the valid period is set as (D ₁ , D ₂ ) = (3, 1).

In the third block, further lower (third hierarchy) classification is shown. For example, if the card to be identified is a bank card of A bank, the branch name is shown, and a value (D ₁ , D ₂ , D ₃ ) is defined as an AA branch at (1,1,1) and an AB branch at (1,1,2). If the card to be identified is a commuter pass, the boarding section is set as (D ₁ , D ₂ , D ₃ ) = ( ₃ , ₁ , ₁ ).

In the fourth block, further lower (fourth hierarchy) classification is shown. For example, if the card to be identified is a bank card of A bank AA branch, customer information such as an account number is shown, and the value of the first block, the value of the second block, the value of the third block, and the fourth block (D ₁ , D ₂ , D ₃ , D ₄ ) are defined as ( ₁ , ₁ , ₁ , ₁ ) as customer AA1, and (1, 1, 1, 2) as customer AA2. Yes.

  The entire identification code specification and identification information shown in FIG. 4 are held in a reader / writer, and each card holds minimum identification data that can be distinguished from other cards. For example, the identification code held on the card of the customer AA2 is composed of 4 blocks, and the entire identification information of 4 blocks is (1, 1, 1, 2). Needless to say, the card may hold user data other than the identification data.

  Further, the communication system of the present embodiment can be composed of a plurality of reader / writers. Since the common identification code specifications recorded in these reader / writers can be centrally managed by the host system of the network connecting these reader / writers, the communication system of the present embodiment can be identified by diversifying data carriers. Easily respond to changes in code specifications.

  In the following, the card 1 (1, 2, 1, 2) and the card 2 (1, 2, 2, 1) are within the communication range of the same reader / writer corresponding to the identification code specification shown in FIG. If they exist, specific operations until the two cards are identified and communication is ended later will be described with reference to FIG. In order to determine the owner of the card, it is assumed that it is necessary to go down to the fourth level which is the lowest level.

Step S1: Comprehensive data (k, D ₁ ) = (1, 1) is constructed using the information for comparison in the first layer having the highest reader / writer, and a REQ ₁ command is issued. Since the information in each of the first information blocks is the same in D ₁ , the card 1 and the card 2 both return a response informing the reader / writer of the match in response to the REQ ₁ command.

Step S2 Since the reply response collides with the issued REQ ₁ command, the reader / writer determines that the response is returned from a plurality of data carriers, and lowers to the second layer in consideration of the current situation. Judge that we should go. Then, the reader / writer takes in the information for comparison in the second layer, constructs comprehensive data (k, D ₁ , D ₂ ) = (2, 1, 1), and issues a REQ ₂ command. Card 1 and card 2 do not reply because the information in their first and second information blocks is different from (D ₁ , D ₂ ).

Step S3 Since there is no response to the issued REQ ₂ command, the reader / writer changes the corresponding comparison information in the second layer, and the total data (k, D ₁ , D ₂ ) = (2, 1, Reconstruct 2) and issue the REQ ₂ command again. Since the information in the first and second information blocks of Card 1 and Card 2 is the same as (D ₁ , D ₂ ), a response that informs the reader / writer that they match in response to the REQ ₂ command Reply together.

Step S4 Since the reply response collided with the issued REQ ₂ command, the reader / writer should determine that the response has been returned from a plurality of data carriers, and take the current situation down to the third layer. Judge. Then, the reader / writer takes in the corresponding comparison information in the third layer, constructs comprehensive data (k, D ₁ , D ₂ , D ₃ ) = ( ₃ , ₁ , ₂ , ₁ ), and generates a REQ ₃ command. Is issued. Since the information in the first, second, and third information blocks is the same as (D ₁ , D ₂ , D ₃ ), the card 1 matches the reader / writer in response to the REQ ₃ command. Returns a response that informs

Step S5 Since there is only one response to the issued REQ ₃ command, the reader / writer determines that there is one data carrier having the same identification code as the comprehensive data, and the returned data carrier On the other hand, necessary communication is performed. In this case, since the identification code is confirmed only up to the third layer, it is necessary to further lower the layer to determine the card holder. This step S5 and the next step S6 are operations for that purpose.

In consideration of the current situation, the reader / writer takes down the corresponding information for comparison in the fourth layer down to the fourth layer, so that the total data (k, D ₁ , D ₂ , D ₃ , D ₄ ) = ( ₄ , 1, 2, 1, 1) and issue a REQ ₄ command. Since neither card 1 nor card 2 has such an identification code, no reply is made.

Step S6: Since there is no response to the issued REQ ₄ command, the reader / writer changes the corresponding comparison information in the fourth layer, and the total data (k, D ₁ , D ₂ , D ₃ , D ₄ ). = (4, 1, 2, 1, 2) and issue the REQ ₄ command again.

  Since the card 1 replies to this command, the owner of the card 1 is determined. Thereafter, after communicating with the determined card according to the purpose of use, the reader / writer transmits a HALT command to the card 1.

Step S7 The reader / writer returns from the current situation to the time when it is determined that there is one data carrier, that is, returns to the time when step S4 is completed, and the third layer comparison information is sent to the remaining corresponding D _3. To the general data (k, D ₁ , D ₂ , D ₃ ) = ( ₃ , ₁ , ₂ , ₂ ) and issue the REQ ₃ command. Since the information in the first, second, and third information blocks is the same as (D ₁ , D ₂ , D ₃ ), the card 2 matches the reader / writer according to the REQ ₃ command. Returns a response that informs

Step S8: Since there is only one reply response to the issued REQ ₃ command, the reader / writer determines that there is one data carrier having the same identification code as the comprehensive data, and the returned data carrier On the other hand, necessary communication is performed. In this case, since the identification code is confirmed only up to the third level, it is necessary to further lower the level and determine the card holder. This step S8 is an operation for that purpose.

In consideration of the current situation, the reader / writer takes down the corresponding information for comparison in the fourth layer down to the fourth layer, so that the total data (k, D ₁ , D ₂ , D ₃ , D ₄ ) = ( ₄ , 1, 2, 2, 1) and issue a REQ ₄ command.

  Since the card 2 replies to this command, the owner of the card 2 is determined. After that, the reader / writer transmits a HALT command to the card 2 after communicating with the confirmed card according to the purpose of use.

Step S9 The reader / writer returns from the current situation to the time when it is determined that there is one data carrier, that is, returns to the time when step S7 ends, and the comparison information of the third hierarchy is sent to the remaining corresponding D _3. Judge that it should be changed. However, as shown in FIG. 4, for (1, 2, D ₃ ), all of the commands related to the comparison information D ₃ that can be taken in the third hierarchy are transmitted. Therefore, the reader writer, up to the second layer, changes the comparison information of the second layer to the rest of the D _2. However, as shown in FIG. 4, for (1, D ₂ ), all the commands related to the comparison information D ₂ that can be taken in the second hierarchy are transmitted. Therefore, the reader / writer goes up to the first layer and changes the comparison information in the first layer to the remaining D ₁ .

The reader / writer constructs comprehensive data (k, D ₁ ) = (1, 2), and issues a REQ ₁ command. Since a data carrier having an identification code that matches such comparison data does not exist within the communication range, the reader / writer does not receive a response.

Step S10 writer further comparative information of the first layer was changed to the rest of the D _1, aggregate data (k, D ₁₎ = a building again (1,3), and issues the REQ ₁ command . In addition, since a data carrier having an identification code that matches such comparison data does not exist within the communication range, the reader / writer does not receive a response.

At this stage, all the commands regarding the comparison information D ₁ that can be taken by the first layer have been transmitted, and the first layer is the top layer. Therefore, the reader / writer terminates communication.

  In the above example, the card is determined by lowering to the fourth hierarchy level, which is the lowest hierarchy, but this is only an example, and the present invention is not limited to this. The reader / writer determines the data carrier by going down to an identifiable hierarchy according to the specification of the identification code. For example, in the example of the commuter pass card shown in FIG.

  As described above, in the communication system and the communication method according to the first embodiment of the present invention, the data carrier has hierarchically stored the unique information such as its use and user, so that it is the same in the communication area of the reader / writer. The presence of multiple data carriers with identification codes eliminates recognition errors, and the reader / writer increases the comparison information for identification by moving down the hierarchy from the highest level as necessary. Since the transmission is performed, the identification code of each data carrier can be recognized by communication with the minimum amount of information. As a result, a communication system with a shortest recognition time can be realized.

  In the above embodiment, the reader / writer and the data carrier have been described as performing wireless communication using electromagnetic inductive coupling. However, the reader / writer and the data carrier may perform wireless communication using other methods such as ultrasonic waves. Alternatively, wired communication may be performed.

  The communication system of the present invention hierarchically holds hierarchical unique identification information that data carriers can identify with each other, and enables identification of data carriers with minimum necessary communication with a reader / writer. This system is useful as a system that can easily cope with a wide variety of IC cards and expansion of users.

It is a figure which shows schematic structure of the communication system by Embodiment 1 of this invention. It is a figure which shows the structure of the identification code of a data carrier in the communication system by the said Embodiment 1. FIG. It is a flowchart which shows the recognition algorithm in the communication system by the said Embodiment 1. FIG. It is a figure which shows the specification of the identification code of a data carrier in Example 1 of the communication system by the said Embodiment 1. FIG. It is a figure which shows the communication operation between the reader / writer and the data carrier in Example 1 of the communication system by the said Embodiment 1. FIG.

Explanation of symbols

1 Reader / Writer 2 Data Carrier 11 Reader / Writer Transmitter 12 Reader / Writer Receiver 13 Reader / Writer Memory 14 Reader / Writer Control Unit 21 Data Carrier Transmitter 22 Data Carrier Receiver 23 Data Carrier Identification Information Storage Unit 24 Data carrier operation

Claims (9)

Communication composed of a plurality of data carriers that are carriers for holding data and a reader / writer that reads and writes data held in the plurality of data carriers, and the reader / writer communicates with each of the plurality of data carriers A system,
Each of the plurality of data carriers is
An identification information storage unit composed of N blocks each holding unique identification information having a hierarchical structure from the first layer to the Nth layer (N is an integer of 2 or more) for identifying the plurality of data carriers from each other;
A calculation unit that compares and calculates the information specified by the instruction signal from the reader / writer and the information held in the identification information storage unit;
A reply unit that performs a reply response according to the result of the comparison operation,
The reader / writer is
A transmitter for transmitting the instruction signal including information for identifying the plurality of data carriers;
A receiving unit for receiving reply responses from the plurality of data carriers,
The transmission unit of the reader / writer includes, for the plurality of data carriers, the information including a layer value k (k is an integer satisfying 1 ≦ k ≦ N) and comparison information corresponding to the k-th block. Send a signal,
Each calculation unit of the plurality of data carriers compares the received comparison information corresponding to the k-th block from the reader / writer with the information actually recorded in each k-th block,
Among the plurality of data carriers, the reply unit of the data carrier in which the two pieces of information match each other returns a response informing the reader / writer that the two pieces of information match.
A communication system characterized by the above. The communication system according to claim 1,
As a result of the transmission, the reader / writer
If the response is not returned, the comparison information corresponding to the kth block is changed,
When the response is returned from only one data carrier, after completing necessary communication with the data carrier, the comparison information corresponding to the k-th block is similarly changed,
When the response is returned from a plurality of data carriers, the layer value k is increased, and the corresponding comparison information is changed to comparison information corresponding to the block corresponding to the increased layer value k. After sending the above instruction signal again,
A communication system characterized by the above. The communication system according to claim 1,
As a result of the transmission by the reader / writer,
Without returning the above response,
And the reader / writer has finished transmitting all corresponding values that the kth block can take to the plurality of data carriers,
And, when k ₀ which is the first layer value when the reader / writer starts communication with the plurality of data carriers is smaller than k,
The reader / writer resets the value of k to the previous value that changes to the current value, and sets the corresponding comparison information to the comparison information corresponding to the block corresponding to the reset k. Send the above instruction signal again after changing
A communication system characterized by the above. The communication system according to claim 1,
As a result of the transmission by the reader / writer,
Without returning the above response,
And the reader / writer has finished transmitting all corresponding values that the kth block can take to the plurality of data carriers,
And, when k ₀ which is the first layer value at the time when the reader / writer starts communication with the plurality of data carriers is equal to k,
The reader / writer terminates communication.
A communication system characterized by the above. The communication system according to claim 1,
The comparison information includes all or a part of information from the first to the (k-1) th block in addition to the information corresponding to the kth block.
A communication system characterized by the above. The communication system according to claim 2,
The required communication is
The reader / writer increases the layer value k, changes the comparison information corresponding to the block corresponding to the increased layer value k, and transmits the instruction signal to identify the one data carrier Including repeated operations,
A communication system characterized by the above. In a communication method for performing communication between a first communication device and a plurality of second communication devices,
Each of the plurality of second communication devices includes N blocks each holding unique identification information from the first layer to the Nth layer that are hierarchized for identifying the plurality of second communication devices from each other. Remembers identification information,
The first communication device transmits an instruction signal including information on the layer value k and comparison information corresponding to the k-th block to the plurality of second communication devices,
The second communication device compares the information included in the received instruction signal from the first communication device with the identification information recorded in each second communication device, and the two pieces of information The second communication device having the same value returns a response informing the first communication device that the match has occurred,
The first communication device receives a response from the second communication device, starts a recognition operation for identifying each of the plurality of second communication devices from the highest layer, and in any layer When a collision error occurs in which two or more second communication devices return responses, the second communication device is moved to the next lower layer to perform a recognition operation. Identify individually,
A communication method characterized by the above. The communication method according to claim 7,
When the collision error occurs, the first communication device moves to a hierarchy one level lower than the position where the collision error occurs in the hierarchy.
A communication method characterized by the above. The communication method according to claim 7,
When the first communication device finishes obtaining all the corresponding comparison information that can be taken in an arbitrary hierarchy that is not the highest hierarchy, the first communication apparatus moves from the hierarchy to a corresponding higher hierarchy and recognizes it. When the operation is continued and all the comparison information that can be taken at the highest level is obtained, the recognition operation is terminated.
A communication method characterized by the above.

Images