Extra exam question E9H03
Subelement E9, ANTENNAS AND TRANSMISSION LINES· Group E9H
What is receiving directivity factor (RDF)?
- A.Forward gain compared to the gain in the reverse direction
- B.Relative directivity compared to isotropic
- C.Relative directivity compared to a dipole
- D.Peak antenna gain compared to average gain over the hemisphere around and above the antenna (correct answer)
WhyReceiving directivity factor (RDF) compares an antenna's peak gain to its average gain over the hemisphere around and above the antenna. Receiving directivity factor (RDF) compares an antenna's peak gain to its average gain over the entire hemisphere surrounding and above it, a single figure that captures how sharply the antenna favors its peak direction versus spreading sensitivity (and picked-up noise) more broadly, answer D. It isn't simply forward-versus-reverse gain, and it isn't gain relative to isotropic or to a dipole specifically, RDF is a distinct figure built around that peak-to-hemispherical-average comparison.
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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