General exam question G9B04
Subelement G9, ANTENNAS AND FEED LINES· Group G9B
What is the radiation pattern of a dipole antenna in free space in a plane containing the conductor?
- A.It is a figure-eight at right angles to the antenna (correct answer)
- B.It is a figure-eight off both ends of the antenna
- C.It is a circle (equal radiation in all directions)
- D.It has a pair of lobes on one side of the antenna and a single lobe on the other side
WhyA dipole antenna's radiation pattern in free space, in a plane containing the conductor, is a figure-eight at right angles to the antenna. In free space, a dipole's radiation pattern in the plane containing the wire itself is a figure-eight, with two lobes pointing broadside (at right angles) to the antenna and nulls off the ends, answer A. It isn't a figure-eight off the ends (that would put the nulls in the wrong place), it isn't a uniform circle in every direction, and it doesn't have an asymmetric lobe pattern with more lobes on one side, so B, C, and D are wrong.
Published 2026-08-28 · Last updated 2026-08-28 · Question text is verbatim from the 2023-2027 NCVEC Element 3 pool (public domain); the explanation above is original writing, see our methodology.
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