Advanced Qualification · A-007 Feedlines and matching · A-007-006-009
If a 3 dBd gain antenna is replaced with a 9 dBd gain antenna, with no other changes, the Effective Radiated Power (ERP) will increase by:
- A 2
- B 4
- C 6
- D 1.5
Correct answer: B — 4. From the official ISED question bank, verified word for word.
Why
A 3 dB increase in antenna gain doubles the Effective Radiated Power, so adding another 3 dB to reach a total 6 dB increase doubles it again. The full explanation — and one for every question — is in Pro.
Practise this section
Feedlines and matching at the advanced level: transmission line theory, impedance transformation, stubs and matching networks.