Advanced Qualification · A-007 Feedlines and matching · A-007-005-009
Une antenne qui répond simultanément à des signaux polarisés horizontalement et verticalement se nomme :
- Aun dipôle replié
- Bune antenne à plan de sol ("ground plane")
- Cune antenne "quad"
- Dune antenne directionnelle hélicoïdale
Correct answer: D — une antenne directionnelle hélicoïdale. Question tirée de la banque officielle d'ISDE.
Why
A helical-beam antenna uses a spiral wire shape that naturally accepts signals regardless of whether they arrive with vertical or horizontal polarization. The full explanation — and one for every question — is in Pro.
Practise this section
Feedlines and matching is section A-007 of the Advanced exam: Feedlines and matching at the advanced level: transmission line theory, impedance transformation, stubs and matching networks.
Drill A-007 — free, no account