optical spectrum frequency communications
41Infrared — For other uses, see Infrared (disambiguation). An image of two people in mid infrared ( thermal ) light (false color) …
42Microwave transmission — The atmospheric attenuation of microwaves in dry air with a precipitable water vapor level of 0.001 mm. The downward spikes in the graph correspond to frequencies at which microwaves are absorbed more strongly, such as by oxygen molecules… …
43Nyquist–Shannon sampling theorem — Fig.1: Hypothetical spectrum of a bandlimited signal as a function of frequency The Nyquist–Shannon sampling theorem, after Harry Nyquist and Claude Shannon, is a fundamental result in the field of information theory, in particular… …
44Multiplexing — General multiplex scheme: the ν input lines channels are multiplexed into a single fast line. The demultiplexer receives the multiplexed data stream and extracts the original channels to be transferred …
45Modulation — For musical change of key, see Modulation (music). For other uses, see Modulation (disambiguation). Passband modulation v · d · e …
46Low-power broadcasting — Contents 1 United States 1.1 FM radio 1.1.1 LPFM classes 1.1.2 …
47radiation — radiational, adj. /ray dee ay sheuhn/, n. 1. Physics. a. the process in which energy is emitted as particles or waves. b. the complete process in which energy is emitted by one body, transmitted through an intervening medium or space, and… …
48Shortwave radio — Shortwave can also refer to a shortwave trough meteorology. A solid state, analog shortwave receiver Shortwave radio refers to the upper MF (medium frequency) and all of the HF (high frequency) portion of the radio spectrum, between… …
49Optics — For the book by Sir Isaac Newton, see Opticks. Optical redirects here. For the musical artist, see Optical (artist). Optics includes study of dispersion of light. Optics is the branch of …
50Power line communication — or power line carrier (PLC), also known as power line digital subscriber line (PDSL), mains communication, power line telecom (PLT), power line networking (PLN), or broadband over power lines (BPL) are systems for carrying data on a conductor… …
