# phase noise ![](attachments/phase%20noise.png#invert) There are two competing definitions, however the IEEE defines phase noise as half the one-sided spectral density of a signal's phase deviation. [^1] ## Jitter The deviation 2from true periodicity of a presumed periodic signal. Plays a role in clock timing for digital circuits. [^2] --- # References [^1]: [Wikipedia](https://en.wikipedia.org/wiki/Phase_noise) [^2]: [Jitter Wiki](https://en.wikipedia.org/wiki/Jitter)