Method of recognizing whether a transponder belongs to a group of transponders

• US 7,737,822 B2
• Filed: 10/31/2003
• Issued: 06/15/2010
• Est. Priority Date: 11/21/2002
• Status: Active Grant

• Current Assignee: NXP B.V. (NXP Semiconductors NV)
• Original Assignee: NXP B.V. (NXP Semiconductors NV)
• Inventors: Cernusca, Michael, Scherabon, Christian, Amtmann, Franz
• Primary Examiner(s): Brown; Vernal U
• Application Number:
  US10/535,348
• Publication Number:
  US 20060077043A1
• Time in Patent Office: 2,419 Days
• Field of Search: 340/10.2, 340/10.1, 340/10.32, 340/10.42, 340/7.44, 340/505, 340/572.4, 340/572.1, 714/6, 342/77
• US Class Current: 340/10.32
• CPC Class Codes: G06K 19/0723 the record carrier comprising an arrangement for non-contact communication, e.g. wireless communication circuits on transponder cards, non-contact smart cards or RFIDs
• CPC Class Codes: G06K 7/0008 General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer
• CPC Class Codes: G06K 7/10039 interrogator driven, i.e. synchronous
• CPC Class Codes: G06K 7/10108 interrogating only those RFIDs that fulfill a predetermined requirement, e.g. selecting all RFIDs having the same speed and moving in a cloud like fashion, e.g. on the same train; interrogating only RFIDs having a certain predetermined temperature, e.g. in the same fridge, another possibility being the active ignoring of a group of tags that fulfill a predetermined requirement, equivalent to the Boolean NOT operation

Abstract

A method recognizes whether a transponder designed for communicating with a communication station belongs to one of at least two groups of transponders. First, for each group of transponders, a check data block that is significant for the group of transponders is generated. Then, the data from the check data block that is significant for the group of transponders is evaluated for the recognition of whether the transponder belongs to the group of transponders.

Claims

1. A method of recognizing whether a transponder designed for communicating with a communication station belongs to one of at least two groups of transponders under which method the communication station designed for communicating with the transponder delivers a request signal to the transponder, which request signal comprises a command data block and a CRC check data block, and under which method, data contained in the request signal is evaluated in the transponder in order to recognize whether the transponder belongs to a group of transponders,

wherein, for each group of transponders, a CRC check data block that is significant for the group of transponders is generated, and

wherein the data that is evaluated for the recognition of whether the transponder belongs to a group of transponders is data from the CRC check data block that is significant for the group of transponders;

wherein the transponders process the command data block only if evaluation of the check data block of the request signal indicates that the transponder belongs to the group of transponders that is identified by the CRC check data block.

2. A communication station for communicating with a transponder, which transponder belongs to one of at least two groups of transponders, wherein the communication station contains means for implementing the method as claimed in claim 1.

3. A communication station as claimed in claim 2, wherein check-data-block generation means is provided and wherein the check-data-block generation means takes the form of CRC-data- block generation means, which CRC-data-block generation means interacts with start-value memory means, which is provided to store a group-significant start value, which group-significant start value is provided in order to influence the generation of the CRC check data block in the CRC-data-block generation means and wherein the start-value memory means is of programmable design and is designed for storing different group-significant start values, which different group-significant start values can be written to the start-value memory means and are responsible for the generation of different CRC check data blocks, of which different CRC check data blocks, each CRC check data block is significant for a group of transponders.

4. A circuit for a communication station for communicating with a transponder, which transponder belongs to one of at least two groups of transponders, wherein the circuit contains means for implementing the method as claimed in claim 1.

5. A circuit as claimed in claim 4, wherein check-data-block generation means is provided and wherein the check-data-block generation means takes the form of CRC-data-block generation means, which CRC-data-block generation means interacts with start-value memory means, which is provided to store a group-significant start value, which group-significant start value is provided in order to influence the generation of the CRC check data block in the CRC-data-block generation means, and wherein the start-value memory means is of programmable design and is designed for storing different group-significant start values that are each assigned to a different group of transponders, which different group-significant start values can be written to the start-value memory means and are responsible for the generation of different CRC data blocks, of which different CRC check data blocks, each CRC check data block is significant for a group of transponders.

6. A transponder for communicating with communication station, which transponder belongs to one of at least two groups of transponders, wherein the transponder contains means for implementing the method as claimed in claim 1.

7. A transponder as claimed in claim 6, wherein check-data-block generation means is provided and wherein the check-data-block generation means takes the form of CRC-data-block generation means, which CRC-data-block generation means interacts with start-value memory means, which is provided to store a group-significant start value, which group-significant start value is provided in order to influence the generation of the CRC check data block in the CRC-data-block generation means, and wherein the start-value memory means is of programmable design and is designed for storing different group-significant start values that are each assigned to a different group of transponders, which different group-significant start values can be written to the start-value memory means and are responsible for the generation of different CRC check data blocks, of which different CRC check data blocks, each CRC check data block is significant for a group of transponders.

8. A transponder as claimed in claim 7, wherein the start-value memory means is designed to store at least two different group-significant start values, and wherein means for sending one group-significant start value selected from the at least two group-significant start values to the CRC-data-block generation means are provided.

9. A circuit for a transponder for communicating with a communication station, which transponder belongs to one of at least two groups of transponders, wherein the circuit contains means for implementing the method as claimed in claim 1.

10. A circuit as claimed in claim 9, wherein check-data-block generation means is provided and wherein the check-data-block generation means takes the form of CRC-data-block generation means, which CRC-data-block generation means interacts with start-value memory means, which is provided to store a group-significant start value, which group-significant start value is provided in order to influence the generation of the CRC check data block in the CRC-data-block generation means, and wherein the start-value memory means is of programmable design and is designed for storing different group-significant start values that are each assigned to a different group of transponders, which different group-significant start values can be written to the start-value memory means and are responsible for the generation of different CRC check data blocks, of which different CRC check data blocks each CRC check data block is significant for a group of transponders.

11. A circuit as claimed in claim 10, wherein the start-value memory means is designed to store at least two different group-significant start values, and wherein means for sending one group-significant start value selected from the at least two group-significant start values to the CRC-data-block generation means are provided.

12. A method as claimed in claim 1, wherein the CRC check data block contains a set of error correction data that is used both for error correction at the transponder and to determine whether the transponder belongs to a particular group of transponders.

13. A circuit for a communication station for communicating with a transponder, which transponder belongs to one of at least two groups of transponders, wherein the circuit contains means for implementing a method for recognizing whether the transponder designed for communicating with the communication station belongs to one of at least two groups of transponders under which method the communication station designed for communicating with the transponder delivers a request signal to the transponder, which request signal comprises a command data block and a CRC check data block, and under which method, data contained in the request signal is evaluated in the transponder in order to recognize whether the transponder belongs to a group of transponders,

wherein, for each group of transponders, a CRC check data block that is significant for the group of transponders is generated, and

wherein the data that is evaluated for the recognition of whether the transponder belongs to a group of transponders is data from the CRC check data block that is significant for the group of transponders;

and

wherein check-data-block generation means is provided and wherein the check-data-block generation means takes the form of CRC-data-block generation means, which CRC-data-block generation means interacts with start-value memory means, which is provided to store a group-significant start value, which group-significant start value is provided in order to influence the generation of the CRC check data block in the CRC-data-block generation means, and wherein the start-value memory means is of programmable design and is designed for storing different group-significant start values that are each assigned to a different group of transponders, which different group-significant start values can be written to the start-value memory means and are responsible for the generation of different CRC check data blocks, of which different CRC check data blocks, each CRC check data block is significant for a group of transponders.

14. A circuit for a transponder for communicating with a communication station, which transponder belongs to one of at least two groups of transponders, wherein the circuit contains means for implementing a method for recognizing whether a transponder designed for communicating with a communication station belongs to one of at least two groups of transponders under which method the communication station designed for communicating with the transponder delivers a request signal to the transponder, which request signal comprises a command data block and a CRC check data block, and under which method, data contained in the request signal is evaluated in the transponder in order to recognize whether the transponder belongs to a group of transponders,

wherein, for each group of transponders, a CRC check data block that is significant for the group of transponders is generated, and

wherein the data that is evaluated for the recognition of whether the transponder belongs to a group of transponders is data from the CRC check data block that is significant for the group of transponders;

wherein check-data-block generation means is provided and wherein the check-data-block generation means takes the form of CRC-data-block generation means, which CRC-data-block generation means interacts with start-value memory means, which is provided to store a group-significant start value, which group-significant start value is provided in order to influence the generation of the CRC check data block in the CRC-data-block generation means, and wherein the start-value memory means is of programmable design and is designed for storing different group-significant start values that are each assigned to a different group of transponders, which different group-significant start values can be written to the start-value memory means and are responsible for the generation of different CRC check data blocks, of which different CRC check data blocks each CRC check data block is significant for a group of transponders.

15. A circuit as claimed in claim 14, wherein the start-value memory means is designed to store at least two different group-significant start values, and wherein means for sending one group-significant start value selected from the at least two group-significant start values to the CRC-data-block generation means are provided.