公开(公告)号：US5627357A

公开(公告)日：1997-05-06

申请号：US456038

申请日：1995-05-31

申请人： Lee M. Cheng ,  Lee L. Cheng ,  Man C. Chu

发明人： Lee M. Cheng ,  Lee L. Cheng ,  Man C. Chu

IPC分类号： G06K19/06 ,  G07F7/08 ,  G06K7/08

CPC分类号： G06K19/06187 ,  G07F7/086

摘要： Magnetic cards are provided with unique card signatures which include a number of bits, some of which have intermediate magnetic levels. As a result a card reader allocates randomly either a one or a zero to the intermediate level bits. The random allocation provides a test for the genuineness of the card. The intermediate level bits are formed as a result of inherent inconsistencies in the characteristic of a normal magnetic stripe along its length. It is not possible therefore to readily, if at all, reproduce patterns of intermediate level bits in a duplicate because the stripe on the duplicate will have differently arranged inconsistencies along its length.

摘要翻译： 磁卡被提供有唯一的卡签名，其包括多个位，其中一些具有中间磁级。 因此，读卡器将中间级位随机分配一个或零。 随机分配提供了卡的真实性的测试。 中间级位由于其沿其长度的正常磁条的特性的固有不一致性而形成。 因此，重复的中间级位重复的模式是不可能的，因为副本上的条带将沿其长度具有不同的排列不一致。