Emphasis (Telecommunications)

In FM transmission, emphasis is the intentional alteration of the amplitude-vs.-frequency characteristics of the signal to reduce adverse effects of noise in a communication system. The high-frequency signal components are emphasized to produce a more equal modulation index for the transmitted frequency spectrum, and therefore a better signal-to-noise ratio for the entire frequency range.
The whole system of preemphasis and deemphasis is called emphasis. The frequency curve is decided by especial time constants. The cutoff frequency can be calculated from that.
Emphasis is commonly used in audio digital recording, record cutting and in FM radio transmission. See also: Federal Standard 1037C and MIL-STD-188.

 

<< PreviousWord BrowserNext >>
earth terminal complex
echo (mythology)
effective data transfer rate
effective earth radius
effective height
effective input noise temperature
effective mode volume
effective power
effective transmission rate
efficiency factor
eia interface
electrical length
electric field
electromagnetic compatibility
electromagnetic environment
electromagnetic interference control
electromagnetic pulse
electromagnetic radiation hazard
electromagnetic survivability
electronic deception
electronic switching system
electronic warfare support measures
electro optic effect
electro optic modulator
electro optics
elliptical polarization
end distortion
end of transmission character
endurability
enhanced service
epoch date
equilibrium length
equivalent noise resistance
equivalent pulse code modulation noise
error
error burst
error correcting code
error detecting system
escape character
essential service
exchange
exempted addressee
extended definition television
extended superframe