Skip to article frontmatterSkip to article content

1Définition

En d’autres termes, un signal est une grandeur physique (tension, courant, pression, etc.) variable qui transporte une information.

Les flux de la chaîne d’information sont des signaux. On retrouve généralement en sortie du bloc Acquérir un signal électrique.

2Les différents types de signaux

2.1Les signaux logiques

Un signal logique ne peut prendre que deux valeurs : un niveau haut (“High”) et un niveau bas (“Low”).

findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
<Figure size 768x432 with 1 Axes>

Figure 1:Exemple de signal logique

Le signal logique en Figure 1 est par exemple à l’état haut entre 2 s et 3 s, et à l’état bas entre 3 s et 6 s. Lorsque le signal passe de l’état bas à l’état haut (comme à 2 s), on parle de front montant. Dans le cas contraire (comme à 3 s), on parle de front descendant.

2.2Les signaux analogiques

Un signal analogique est un signal qui peut prendre un ensemble continu de valeurs. Un exemple de signal analogique est donné en Figure 2.

findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
<Figure size 768x432 with 1 Axes>

Figure 2:Exemple de signal analogique

2.3Les signaux numériques

Un signal numérique est un signal qui peut prendre un ensemble discret de valeur, c’est-à-dire un ensemble précis de valeurs distinctes (généralement des nombres entiers). Un exemple de signal analogique est donné en Figure 3.

findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
findfont: Font family 'Fira Code' not found.
<Figure size 768x432 with 1 Axes>

Figure 3:Exemple de signal numérique