What is Random Noise?

Random noise is an unwanted disturbance or random signal that interferes with a desired signal, making it harder to process or interpret. For example, in a phone call, your voice is the desired signal, while background noise like traffic or wind is a form of noise that can make the conversation harder to hear.

Why is it called random noise? It’s because its values change randomly over time without any deterministic or repeating behavior.

Random noise is not typically considered an elemental signal because it is not used to analyze or decompose other signals. Instead, it is usually something that needs to be filtered or minimized.

The energy distribution across frequencies determines the "color" of noise. For instance, you may have heard of "white noise". In white noise, the energy is equally distributed across all frequency bins, meaning it has constant energy at all frequencies. On the other hand, in pink noise, the energy decreases as the frequency increases. The amplitude of random noise can follow a Gaussian distribution.

There are several methods to eliminate or reduce random noise in signals, such as using noise filtering techniques.

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