Extra exam question E9B08
Subelement E9, ANTENNAS AND TRANSMISSION LINES· Group E9B
What is the far field of an antenna?
- A.The region of the ionosphere where radiated power is not refracted
- B.The region where radiated power dissipates over a specified time period
- C.The region where radiated field strengths are constant
- D.The region where the shape of the radiation pattern no longer varies with distance (correct answer)
WhyAn antenna's far field is the region where the shape of the radiation pattern no longer varies with distance. An antenna's far field is the region far enough away that the shape of its radiation pattern no longer changes as you move farther from the antenna, only the signal strength continues to drop off with distance, answer D. It isn't a region of the ionosphere, isn't defined by power dissipating over a set time period, and field strengths certainly aren't constant there, they still fall off with distance, only the pattern's shape has stabilized.
Published 2026-08-28 · Last updated 2026-08-28 · Question text is verbatim from the 2024-2028 NCVEC Element 4 pool (public domain); the explanation above is original writing, see our methodology.
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