Definition of D layer in English:

D layer

Syllabification: D lay·er

noun

The lowest layer of the ionosphere, able to reflect low-frequency radio waves.
More example sentences
  • They will penetrate to the D-layer and increase the ionisation process and the electron density.
  • The ionospheric D-layer is a narrow bandwidth radar target often with a very small scattering cross section.
  • Simply due to the height difference of the ‘responsible’ layer, troposcatter is useful up to distances of 700 Km, whereas D-layer is at best in the 600/1300 Km range.

Origin

1930s: from an arbitrary use of the letter D.

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