 Noise (signal processing)

Noise is unwanted variation in a signal. Whether a component is unwanted depends on the measurement task: suppressing fast variation helps only when that variation is expendable. White noise provides one mathematical model; it does not describe every source of disturbance. A linear filter may reduce some noise while also altering the desired signal.

In signal processing, "noise" refers to any unwanted or irrelevant information that distorts or interferes with the desired signal. Noise can originate from various sources and can exhibit different characteristics, depending on its nature. There are several types of noise, including: 1. **White Noise**: Contains equal intensity at different frequencies and is often characterized by a flat spectral density. It is analogous to the sound of static.