d region

Other Definitions
d region (dict)

The D region is the portion of the ionosphere that exists approximately 50 to 95 km above the surface of the Earth. Note: Attenuation of radio waves, caused by ionospheric free-electron density generated by solar radiation, is pronounced during daylight hours. Because solar radiation is not present at night, ionization ceases, and hence attenuation of radio waves ceases. Source: from Federal Standard 1037C and from MIL-STD-188

<< Previous

Word Browser

Next >>

digital signal 0
digital subscriber line
digital transmission group
digitizer
digroup
direct access
direct connect
direct distance dialing
directional coupler
directive gain
direct sequence spread spectrum

disengagement originator
dispersion limited operation
distortion
distortion limited operation
distributed database
distributed queue dual bus
distributed switching
disturbance voltage
diurnal phase shift
diversity reception
dod master clock

double ended synchronization
double sideband reduced carrier transmission
double sideband suppressed carrier transmission
doubly clad fiber
drift
drop (liquid)
drop and insert
dropout
dual access
dual in line package
duct

duobinary signal
duplexer
duty cycle
dynamic range
earth terminal complex
echo (mythology)
effective data transfer rate
effective earth radius
effective height
effective input noise temperature
effective mode volume