Information identification system for identifying response units by a control unit, and the control unit and the response units for the information identification system

• US 6,134,692 A
• Filed: 03/20/1998
• Issued: 10/17/2000
• Est. Priority Date: 03/21/1997
• Status: Expired due to Fees

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Iwasaki, Kazunori, Uehara, Kensuke, Sekiya, Kunihiko, Nitta, Katsumi, Karasawa, Hirobumi, Hashimoto, Satoru, Okano, Michiaki, Kuma, Katsuhiko
• Primary Examiner(s): Baker, Stephen M.
• Application Number:
  US09/044,925
• Time in Patent Office: 942 Days
• Field of Search: 714/748, 714/749, 340/825.03, 340/825.04, 340/825.06, 340/825.07, 340/825.08, 340/825.21, 340/825.44, 340/825.52, 340/825.53, 340/825.54, 370/346, 370/347, 370/348, 370/349
• US Class Current: 714/749
• CPC Class Codes: G06K 7/10029 the collision being resolved in the time domain, e.g. using binary tree search or RFID responses allocated to a random time slot
• CPC Class Codes: H04L 1/0061 Error detection codes

Abstract

A control unit transmits address area designation information designating an arbitrary bit position in ID data. At least a response unit transmits a response signal with an error detection code attached to predetermined information in the unique information held in itself by means of a time slot determined by the address area designation information and the ID data of the particular response unit. The control unit checks for the presence or absence of an error of the information in each time that has arrived, fetches only the response signal free of error, and transmits the error presence-absence information indicating the inspection result. Further, in the case where there exists a time slot having an error, the control unit transmits new address area designation information. In the case where an error exists in the time sot used previously by the response unit, the response unit retransmits the response signal in the time slot determined from the new address area designation information and the ID data of the response unit.

Claims

1. An information identification system comprising a plurality of response units and a control unit, said plurality of response units each containing unique identification data being binary data of a plurality of bits, said control unit reading at least part of the identification data from said plurality of response units, said information identification system further comprising:

bit position designation means, arranged in said control unit, for producing predetermined bit position information and transmitting it to a predetermined downlink, said bit position information designating an arbitrary bit position in said identification data;

response information transmission means, arranged in each of said plurality of response units, for producing predetermined response information and transmitting it to a predetermined uplink in predetermined time slots, in response to an arrival of said bit position information transmitted by said bit position designation means, said response information pieces each containing at least part of the identification data and an error detection code of a corresponding one of said plurality of response units, said time slots used by respective response units to transmit said response information being determined in accordance with states of bit strings at the bit position in the identification data, which is indicated in said bit position information;

error inspection means, arranged in said control unit, for inspecting for presence or absence of an error in the response information pieces contained in each time slot and arriving through said uplink, based on said error detection codes in said response information pieces; and

response information fetching means, arranged in said control unit, for fetching only response information pieces that have arrived in time slots determined to have no error by said error inspection means.

2. An information identification system according to claim 1, further comprising:

identification data judging means, arranged in said control unit, for judging the identification data of said plurality of response units that have transmitted said response information pieces, on the basis of the response information pieces fetched by said response information fetching means during a predetermined period of time;

determination requesting means, arranged in said control unit, for transmitting predetermined determination request data through said downlink to each of said plurality of response units having the identification data judged by said identification data judging means, in response to said error inspection means ceasing to detect a time slot having an error, said determination request data representing both of (i) common information indicating one bit string common to identification data pieces which are grouped together as having a same state at a same bit position and (ii) individual information indicating bit strings at remaining bit positions for each of the identification pieces, in cases where there are a plurality of identification data pieces being the same in state in the same bit position;

determination notification means, arranged in each of said plurality of response units, for producing predetermined determination notification information containing identification data of said plurality of response units and transmitting it to said uplink, in response to an arrival at said plurality of response units of said determination request data transmitted from said determination requesting means, said determination notification means, in cases where the arrived determination request data contains the grouped identification data, determining whether the arrived determination request data is self-addressed by (i) combining said individual information with said common information to judge the identification data and (ii) determining if the combined identification data is identical to that of the corresponding response unit;

response information determining means, arranged in said control unit, for receiving said determination notification information transmitted by said determination notification means and determining as effective only the response information pieces based on which said identification data judging means has judged the identification data contained in said determination notification information.

3. An information identification system according to claim 1, further comprising:

identification data judging means, arranged in said control unit, for judging the identification data of said plurality of response units that have transmitted said response information pieces, on the basis of the response information pieces fetched by said response information fetching means during a predetermined period of time;

determination requesting means, arranged in said control unit, for transmitting predetermined determination request data through said downlink to each of said plurality of response units having the identification data judged by said identification data judging means, in response to said error inspection means ceasing to detect a time slot having an error, said determination requesting means imparting only a bit string at said bit position to said determination request data if there is any identification data with a state of a bit position of a predetermined part thereof different from that of any of the remaining identification data;

determination notification means, arranged in each of said plurality of response units, for producing predetermined determination notification information and transmitting it to said uplink, in response to the arrival at said plurality of response units of said determination request data transmitted from said determination requesting means, said determination notification means determining whether said arriving determination request data is self-addressed by, in cases where said arriving determination request data only contains a bit string at a bit position, determining whether the identification data of the corresponding response unit has a same number of bit strings at a predetermined bit position coincident with the bit string; and

response information determining means, arranged in said control unit, for receiving said determination notification information transmitted by said determination notification means and determining as effective only the response information based on which said identification data judging means has judged the identification data of said plurality of response units that have transmitted said determination notification information.

4. An information identification system according to claim 1, further comprising:

response information determining means, arranged in said control unit, for fetching only response information pieces that have arrived in a time slot determined to have no error by said error inspection means and determining said fetched response information pieces as effective response information;

identification data judging means, arranged in said control unit, for judging the identification data of said plurality of response units that have transmitted said response information pieces, on the basis of the response information pieces determined as effective by said response information determining means;

read result notification means, arranged in said control unit, for producing predetermined read result notification information and transmitting it to said downlink in response to said error inspection means ceasing to detect the time slot having an error, said read result notification information containing the identification data judged by said identification data judging means;

read result holding means, arranged in each of said response units, for judging whether the identification data contained in said read result notification information transmitted by said read result notification means contains the identification data identical to that held in the corresponding response unit, and holding the judgment result;

repetitive read designation means, arranged in said control unit, for producing predetermined repetitive read designation information and transmitting it to said downlink, said repetitive read designation information designating an arbitrary bit position in said identification data and designating a repetitive read mode, said repetitive read designation information being transmitted after transmission of said read result notification information by said read result notification means;

repetitive read response means, arranged in each of said response units, for causing said response information transmission means to transmit the response information pieces as long as (i) said repetitive read designation information transmitted by said repetitive read designation means arrives and (ii) a judgement result held in said read result holding means of the corresponding response unit does not indicate that the identification data held in the corresponding response unit is contained in said read result notification information; and

repetitive read control means, arranged in said control unit, for causing said repetitive read designation means to repeat its processing operations until said response information ceases to be transmitted from any one of the response units as a result of transmission of said repetitive read designation information by said repetitive read designation means.

5. An information identification system according to claim 4, wherein

when the identification data judged by said identification data judging means contains a plurality of identification data pieces which are the same in state at the same bit position, said read result notification means groups them together and imparts to said read result notification information one bit string which is in the same state at the same bit position and is common to the grouped identification data pieces as common information and bit strings at remaining bit positions for each of the identification pieces as individual information;

and

when the arriving read result notification information contains the grouped identification data pieces, said read result holding means judges said identification data pieces by combining said common information with said individual information and determines whether the combined identification data is identical to that of the corresponding response unit.

6. An information identification system according to claim 4, wherein

said read result notification imparts to the read result notification information only the bit string at the bit position if there is an identification data piece which is different from the remaining identification data pieces in terms of the state of the bit position at its low-order part;

and

when the arriving read result notification information only contains a bit string at a bit position said, read result holding means judges whether the identification data contained in said read result notification information contains the identification data identical to that held in the corresponding response unit based on whether or not the bit string coincides with that having the same number of low-order bits in the identification data held in the corresponding response unit.

7. An information identification system according to claim 1, wherein said bit position information is a binary data of a plurality of bits, and said response information transmission means selects one time slot from a number of time slots in accordance with a state of a bit string at a bit position of the identification data of the corresponding response unit, the state of the bit position being the same as a predetermined state of the bit position in the bit position information, and the number of the time slots being determined based on a value of the bit in a predetermined state.

8. An information identification system according to claim 1, further comprising:

inspection result notification means, arranged in said control unit, for producing predetermined inspection result information and transmitting it to said downlink, said inspection result information indicating the inspecting result of said error inspection means.

9. An information identification system according to claim 8, further comprising:

repetitive requesting means, arranged in said control unit, for causing said bit position information designating means to transmit bit position information designating a bit position different from the previously-designated bit position, in response to the detection by said error inspection means of at least one time slot that has developed an error;

repetitive response means, arranged in each of said response units, for causing said response information transmission means to transmit the response information pieces to said uplink in a time slot, the time slot being selected based on the state of the bit string at the bit position indicated by said bit position information newly transmitted by said bit position designation means in the identification data held in the corresponding response unit.

10. An information identification system according to claim 9, wherein said repetitive response means select one time slot from a number of time slots on the basis of the state of the bit string at the bit position indicated by said bit position information, the number of the time slots being equivalent to a product of the number of bit positions indicated by said bit position information and the number of the time slots which have been determined to contain errors in said inspection result information notified by said inspection result notification means.

11. A control unit constituting an information identification system with a plurality of response units, each of which contains unique identification data being binary data of a plurality of bits, and reading at least part of identification data from said plurality of response units, said control unit comprising:

bit position designation means for producing predetermined bit position information and transmitting it to a predetermined downlink, said bit position information designating an arbitrary bit position in said identification data;

error inspection means for inspecting for presence or absence of an error in the response information pieces contained in each time slot and arriving through said uplink, based on said error detection codes in said response information pieces; and

response information fetching means, arranged in said control unit, for fetching only response information pieces that have arrived in time slots determined to have no error by said error inspection means.

12. A control unit according to claim 11, further comprising:

response information determining means for fetching only response information pieces that have arrived in a time slot determined to have no error by said error inspection means and determining said fetched response information pieces as effective response information;

identification data judging means, arranged in said control unit, for judging the identification data of said plurality of response units that have transmitted said response information pieces, on the basis of the response information pieces determined as effective by said response information determining means;

read result notification means for producing predetermined read result notification information and transmitting it to said uplink in response to said error inspection means ceasing to detect the time slot having an error, said read result notification information containing the identification data judged by said identification data judging means;

repetitive read designation means for producing predetermined repetitive read designation information and transmitting it to said downlink, said repetitive read designation information designating an arbitrary bit position in said identification data and designating a repetitive read mode, said repetitive read designation information being transmitted after transmission of said read result notification information by said read result notification means; and

repetitive read control means for causing said repetitive read designation means to repeat its processing operations until said response information ceases to be transmitted from any one of the response units as a result of the transmission of said repetitive read designation information by said repetitive read designation means.

13. A control unit according to claim 11, further comprising inspecting result notification means for producing predetermined inspection result information indicating the inspection result of said error inspection means and transmitting it to said downlink.

14. A control unit according to claim 11, further comprising repetitive response means for causing said bit position designating means to transmit bit position information designating a bit position different from the previously-designated bit position, in response to the detection by said error inspection means of at least one time slot that has developed an error.

15. A control unit according to claim 11, further comprising:

identification data judging means for judging the identification data of said plurality of response units that have transmitted said response information pieces, on the basis of the response information pieces fetched by said response information fetching means during a predetermined period of time;

determination requesting means for transmitting predetermined determination request data through said downlink to each of said plurality of response units having the identification data judged by said identification data judging means, in response to said error inspection means ceasing to detect a time slot having an error, said determination request data containing at least one of (i) common information indicating one bit string common to identification data pieces which are grouped together as having a same state at a same bit position and (ii) individual information indicating bit strings at remaining bit positions for each of the identification pieces; and

response information determining means for receiving said determination notification information transmitted by said plurality of response units in response to the transmission of said determination requesting data by said determination requesting means and determining as effective only the response information pieces based on which the base on which said identification data judging means has judged the identification data contained in said determination notification information.

16. A control unit according to claim 11, further comprising:

identification data judging means for judging the identification data of said plurality of response units that have transmitted said response information pieces, on the basis of the response information pieces fetched by said response information fetching means during a predetermined period of time;

determination requesting means, arranged in said control unit, for transmitting predetermined determination request data through said downlink to each of said plurality of response units having the identification data judged by said identification data judging means, in response to said error inspection means ceasing to detect a time slot having an error, said determination requesting means imparting only a bit string at said bit position to said determination request data if there is any identification data with a state of a bit position of a predetermined part thereof different from that of any of the remaining identification data; and

response information determining means for receiving said determination notification information transmitted by said plurality of response units in response to the transmission of said determination requesting data by said determination requesting mean and determining as effective only the response information pieces providing the base on which said identification data judging means has judged the identification data of said plurality of response units that have transmitted said determination notification information.

17. A control unit according to claim 11, wherein said repetitive requesting means causes said bit position designation means to designate a bit position different from the previously-designated bit position in order to set a plurality of new time slots in corresponding to the original time slot that has developed an error, and controlling said bit position designated by bit position designation means in such a manner as to reduce the number of the new time slots corresponding to the original time slot in the case where the total number of the new time slots exceeded a predetermined limit.

18. A control unit according to claim 11, wherein said repetitive requesting means causes said bit position designation means to designate a bit position different from the previously-designated bit position in order to set a plurality of new time slots in corresponding to the original time slot that has developed an error, and wherein

in the case where the total number of the new time slots exceeds a predetermined limit, said original time slots are divided into a plurality of groups in such a manner that the total number of new time slots set for each of said original time slots included in each of said groups may not exceed said limit, and wherein

the slot designation information for designating the original time slots included in each of said groups are sequentially transmitted to said downlink at different time points, while at the same time causing said bit position designation means to transmit the same bit position designation information at said different time points.

19. A response unit constituting an information identification system with a control unit for reading the required information and having unique identification data which is binary data of a plurality of bits, said response unit comprising:

a plurality of response information transmission means for producing predetermined response information pieces respectively and transmitting them to a predetermined uplink in predetermined time slots, in response to an arrival of said bit position information transmitted by said bit position designation means, said response information pieces each containing at least part of the identification data and an error detection code of a corresponding one of said plurality of response units, said time slots used by respective response units to transmit said response information being determined in accordance with states of bit strings at the bit position in the identification data, which is indicated in said bit position information.

20. A response unit according to claim 19, further comprising:

read result holding means for judging whether the identification data contained in said read result notification information transmitted by said control unit contains the identification data identical to that held in the corresponding response unit, and holding said judgement; and

repetitive read response means for causing said response information transmission means to transmit the response information pieces as long as (i) said repetitive read designation information transmitted by said repetitive read designation means arrives and (ii) a judgement result held in said read result holding means of the corresponding response unit does not indicate that the identification data held in the corresponding response unit is contained in said read result notification information.

21. A response unit according to claim 19, wherein said bit position information is a binary data of a plurality of bits, and said response information transmission means selects one time slot from a number of time slots on a basis of a relationship between the arrangement of a predetermined state of bit position in the bit position information and the identification data of the corresponding response unit, the number of the time slots being determined based on a number of bits in a predetermined state.

22. A response unit according to claim 19, further comprising:

repetitive response means for causing said response information transmission means to transmit the response information pieces to said uplink in a time slot upon receipt from said control unit of inspection result information indicating judgement that an error exists in the time slot, the time slot being determined based on a state of a bit string at a bit position of the identification data held in the corresponding response unit, the bit position being indicated in bit position information newly transmitted from said bit position designation means.

23. A response unit according to claim 22, wherein said repetitive response means select one time slot from a number of time slots on the basis of the state of the bit string at the bit position indicated by said bit position information, the number of the time slots being equivalent to a product of the number of bit positions indicated by said bit position information and the number of the time slots which have been determined to contain errors in said inspection result information notified by said inspection result notification means.

24. A response unit according to claim 19, further comprising determination notification means for producing predetermined determination notification information containing identification data of said plurality of response units and transmitting it to said uplink, in response to an arrival at said plurality of response units of said determination request data transmitted from said control unit, said determination notification means, in cases where the arrived determination request data contains the grouped identification data, determining whether the arrived determination request data is self-addressed by (i) combining said individual information with said common information to judge the identification data and (ii) determining if the combined identification data is identical to that of the corresponding response unit.

25. A response unit according to claim 19, further comprising determination notification means for producing predetermined determination notification information and transmitting it to said uplink, in response to the arrival at said plurality of response units of said determination request data transmitted from said control unit, said determination notification means determining whether said arriving determination request data is self-addressed by, in cases where said arriving determination request data only contains a bit string at a bit position, determining whether the identification data of a corresponding response unit has a same number of bit strings at a predetermined bit position coincident with a bit.

26. A response unit according to claim 19, wherein said response information transmission means causes said response information to include only the bit string at the bit positions other than the bit positions thus far designated by said control unit in the identification data held in the corresponding response unit.