White noise是什麼意思
"White noise" is a term that is used in various contexts, including physics, engineering, and more commonly in the field of sound. In each of these areas, it generally refers to a consistent, random signal or sound that lacks any distinguishable pattern. Here are the main definitions:
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Physics and Engineering: In physics and engineering, white noise refers to a signal or a sound with a flat power spectral density. This means that the signal contains equal power within a fixed bandwidth at any given frequency. In other words, it's a random signal that has equal power per hertz in a specified range of frequencies. This type of noise is often used in testing and analysis to simulate real-world conditions or to test the performance of systems under random input.
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Sound and Audio: In the context of sound, white noise is a type of noise that is produced by a random signal with equal power per frequency within the bandwidth of human hearing. It sounds like a hiss or a low-level static when heard through speakers or headphones. White noise is often used in audio applications to mask other sounds or as a sleep aid because of its consistent, unobtrusive nature.
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General Usage: In a more general sense, "white noise" can refer to any kind of consistent, random, and unstructured input or information that lacks any meaningful pattern or content. It's often used metaphorically to describe confusing or indistinct speech, background chatter, or random data.
In popular culture and media, the term "white noise" is often used metaphorically to describe something that is constant and unremarkable, or to refer to background noise that is not distracting.