Can be defined as undesirable electrical signals, which distort or interfere with an original (or desired) signal. Noise could be transient (temporary) or constant. Unpredictable transient noise is caused, for example, by lightning. Constant noise can be due to the predictable 50 or 60 Hz AC 'hum' from power circuits or harmonic multiples of power frequency close to the data communications cable. This unpredictability makes the design of a data communications system quite challenging.
Noise can be generated from within the system itself (internal noise) or from an outside source (external noise).
Based on book: Brown, Mark. Practical Grounding, Bonding, Shielding and Surge Protection. Australia, 2004
Nenhum comentário:
Postar um comentário