Thermal noise, also known as Johnson-Nyquist noise, refers to random electrical fluctuations that occur in conductors or resistors due to thermal agitation of charge carriers, usually electrons. This phenomenon is inherent to all electronic components and increases with temperature. Thermal noise is characterized by a flat power spectral density across a wide frequency range, meaning that it contributes equally to the noise floor at all frequencies within a specified bandwidth.
Thermal energy noise refers to random vibrations or fluctuations in physical systems, including electronic circuits, caused by thermal energy present in the environment. In electronic circuits, this manifests itself as thermal noise, where agitation of charge carriers due to thermal energy leads to random voltage fluctuations.
The thermal noise function describes the statistical distribution of thermal noise in electronic systems. It generally follows a Gaussian (normal) distribution, where the amplitude of noise fluctuations varies randomly around a mean value. This feature is important for understanding the characteristics of noise in electronic circuits and for designing systems that can mitigate its effects on signal quality.
In the context of signal-to-noise ratio (SNR), thermal noise refers to the level of background noise caused by thermal agitation in electronic components. SNR quantifies the ratio of signal power to noise in a communications or measurement system. Thermal noise sets a fundamental limit to the minimum detectable signal resistance, because signals must be distinguishable from background noise to be detected and interpreted reliably.
In chemistry, thermal noise can refer to random fluctuations or variations observed in physical and chemical processes due to thermal energy. For example, in spectroscopy or analytical chemistry, thermal noise can affect measurements by introducing random errors or uncertainties in readings. Managing and understanding thermal noise is crucial to ensure the accuracy and reliability of experimental results in various branches of chemistry.