Patent EP0709803A2 successfully refreshed from Google Patents.
EP0709803A2
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Contactless IC card system and communication method thereof
Assignee: Mitsubishi Electric Corp
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Filing: 1995-10-05
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Granted: —
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Expires: 2015-10-05
Abstract
Abstract Even when a plurality of cards have entered an communication area, the cards within the communication area may be accessible, and, if a data collision occurs, the order of accessing to the cards is expeditiously determined to perform an efficient communication. Each card determines a timing for returning a response block containing an ID code based on conditions directed by a read/write device and the ID code of its own. The read/write device is caused to receive the response block returned by the contactless IC card and to detect a data collision. Based on this result, the conditions are changed so that a respective response block containing an ID code is returned again, thereby concurrently processing the plurality of contactless IC cards.
Inventors
- 👤 Shigeru c/o Mitsubishi Denki K.K. Furuta
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 21:12
CPC Classifications
G; G06; G06K; G06K17/00; G06K7/00; G06K7/10; G06K7/10009; G06K7/10019; G06K7/10029; G06K7/10059; G06K7/0008; G07; G07B; G07B15/00; G07B15/02; G07C; G07C9/00; G07C9/20; G07C9/28
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
157 words
A contactless IC card system including contactless IC cards and a read/write device to perform communication by means of an electromagnetic wave, said contactless IC card system comprising: ID code acquisition means for reading ID codes of said contactless IC cards by said read/write device; and data communication means for identifying contactless IC cards for communication based on the obtained ID codes to cause respective commands to be executed; wherein said ID code acquisition means determining each timing at which the respective contactless IC card returns a response block containing an ID code based on conditions directed to the respective card from the read/write device and the own ID code; and the read/write device receiving the response block returned by the contactless IC card and detecting a data collision and, based on this result, requesting returning of a response block containing ID code again with conditions being changed to concurrently process a plurality of contactless IC cards.
Claim 2
Dependent Claim
51 words
The contactless IC card system according to claim 1 wherein said ID code acquisition means concurrently executes ID code acquisition and data communication for executing respective commands with contactless IC cards for communication being identified based on obtained ID codes by means of one command block transmitted by said read/write device.
Claim 3
Dependent Claim
55 words
The contactless IC card system according to claim 1, further comprising counting means for counting contactless IC cards entering into the communication area within a predetermined time period, and wherein said ID code acquisition means determines number of returning timings for response block containing an ID code based on count result of the counting means.
Claim 4
Dependent Claim
167 words
A communication method of contactless IC card system including contactless IC cards and a read/write device for performing communication by means of an electromagnetic wave, said communication method of contactless IC card system comprising the steps of: acquiring ID code by reading the ID codes of the contactless IC cards by the read/write device; and communicating data by identifying contactless IC cards for communication based on the obtained ID codes to cause respective commands to be executed; wherein each timing at which the respective contactless IC card returns a response block containing an ID code is determined in said step of acquiring ID code based on conditions directed to the respective card from the read/write device and its own ID code; the read/write device receiving the response block returned by the contactless IC card and detecting a data collision and, based on this result, requesting returning of a response block containing ID code again with conditions being changed to concurrently process a plurality of contactless IC cards.
Claim 5
Dependent Claim
57 words
The communication method of contactless IC card system according to claim 4 wherein, in said step of acquiring ID code, ID code acquisition and data communication for executing respective commands with contactless IC cards for communication being identified based on obtained ID codes are concurrently executed by means of one command block transmitted by said read/write device.
Claim 6
Dependent Claim
62 words
The communication method of contactless IC card system according to claim 4, further comprising the step of counting contactless IC cards entering the communication area within a predetermined time period, and wherein number of returning timings for a response block containing an ID code is determined in said step of acquiring ID code based on a count result the step of counting.
References Cited (Backward Citations)
JPH02148282A
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JPH02226392A
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JPH02226390A
Cited
JPH032271A
Cited
JPH0449078A
Cited
JPH05159114A
Cited
JPH061512A
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