Basic Qualification · B-007 Radio wave propagation · B-007-008-002
Si vous recevez un signal faible et déformé presque à la fréquence maximale utilisable, de quel type de propagation s'agit-il probablement?
- ADe la propagation par diffusion ionosphérique
- BDe la propagation par onde de sol
- CDe la propagation en visibilité directe
- DDe la propagation troposphérique guidée (par conduit)
Correct answer: A — De la propagation par diffusion ionosphérique. Question tirée de la banque officielle d'ISDE.
Why
Scatter happens when radio waves bounce off irregularities in the upper atmosphere, sending a small, weak, and often distorted signal back to Earth even when the frequency is near the maximum usable limit. The full explanation — and one for every question — is in Pro.
Practise this section
Radio wave propagation is section B-007 of the Basic exam: How signals travel: the ionosphere and its layers, skip, ground wave, sporadic E, and which bands work when.
Drill B-007 — free, no account