modal noise - technical definition
- Noise caused by interactions between the fiber and the connectors, modal noise results in power fluctuations at the receivers, increasing the signal-to-noise ratio (SNR) and limiting the length of the fiber link. Modal noise occurs only when high power lasers are used in conjunction with multimode fiber (MMF). See also SNR.
- Noise generated in a multimode fiber optic transmission system (FOTS) by the combination of mode-dependent attenuation and fluctuations in the distribution of optical energy, i.e., optical power density, among the guided modes or in their relative phases. Synonymous with speckle noise. See also MMF and power density.