Using a simple analogy with the ordinary language the author explains the error detecting and correcting codes principle. He shows how the transmission of the two french words: MARCHE and ARRETE to a transport vehicle's driver is in fact a code, implicitly understood by every person knowing the french orthography. Indeed the first letter is sufficient to bring all the useful meaning (respectively the orders: GO and STOP) and the five last letters are nothing else but the redundant part of a code. Any orthography's error reveals a transmission's fault, and providing these faults are not too numerous everybody can guess the real word. The author next estimates the safety of such an orthographic code by computing the probability that several transmission faults can succeed in transforming the word ARRETE to the word MARCHE. He shows that this safety is only related to the total number of redundant letters of the code's words and of their distance. Distance means here the number of letters by which two code's words are different. In a second part the author transfers the above ideas into the binary codes field and he writes a mathematical formular allowing the calculation of the safety of any binary code (provided that some hypotheses, stated in the paper, are fullfilled) using only the total number of bits of the transmitted words and of the Hamming distance between the code's words.
Securite de la transmission. Application aux systemes de transport
Anwendung der Uebertragungssicherheit auf Transportsysteme
Application of transmission reliability on transport systems
Onde Electrique ; 67 , 3 ; 112-122
1987
11 Seiten, 2 Bilder, 10 Quellen
Aufsatz (Zeitschrift)
Französisch
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