The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.

The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.

Date of Patent:
Mar. 31, 1992

Filed:

Sep. 10, 1990
Applicant:
Inventor:

Pierre Periou, Cergy Pontoise, FR;

Assignee:

Rockwell International Corporation, Pittsburgh, PA (US);

Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04K / ; H04L / ; H01H / ; G07D / ;
U.S. Cl.
CPC ...
380 23 ; 200 4301 ; 235 27 ; 34082534 ; 380 42 ; 380 43 ; 380 48 ;
Abstract

In this method, a number N is assigned to transmitted and receiving stations comprising synchronous clocks (2), the coded message being obtained by calculating a time Tie from the time elapsed since the initialization of the clock of the transmitting station, a code Ae1 from N and from Tie in accordance with a first relationship, a code Ae2 from Ae1 in accordance with a second relationship, and the coded message M from N, Tie and Ae2, in accordance with a third relationship. The validation operation is performed by calculating a time Tir1 from the time elapsed since the initialization of the clock of the receiving station, a code Ar1 from the received coded message M, from N and from Tir1, by using the third relationship, a code Ar2 from the n highest order bits of Ar1, n being the number of bits of Ae1, a code Ar3 from Ar2 in accordance with the second relationship, a time Tir2 from M, from N and from Ar3, by using the third relationship, and a code Ar4 from N and from Tir2 by using the first relationship, and by verifying that Ar2 is equal to Ar4 and that the absolute value of the difference Tir2-Tir1 is less than a specified threshold.


Find Patent Forward Citations

Loading…