Abstract: Disclosed are a method and a device for the convolutive encoding of blocks each formed by a predetermined number N of source data elements, wherein each of said source data elements is introduced twice into one and the same convolutive encoder implementing a generating polynomial with a period L in an order such that the two instances of introduction of one and same source data element d.sub.i are separated by the introduction of (p.sub.i.L)-1 other source data elements, p.sub.i being a non-zero integer. Also disclosed are a corresponding decoding method and device that can be applied, in particular, to the transmission of short messages, for example in radiotelephony, for satellite communications or gain computer telecommunications (Internet for example). FIG. 2.
Type:
Grant
Filed:
April 19, 1998
Date of Patent:
September 12, 2000
Assignee:
France Telecom & Telediffusion de France S.A.
Abstract: Method of electronic payment by chip card.According to the invention, each token carries a number making it possible to check its authenticity.The invention is used for electronic payment.
Type:
Grant
Filed:
August 16, 1993
Date of Patent:
April 19, 1994
Assignees:
France Telecom, Telediffusion de France S.A., U.S. Philips Corporation