Extra exam question E9C14
Subelement E9, ANTENNAS AND TRANSMISSION LINES· Group E9C
How does the radiation pattern of a horizontally-polarized antenna mounted above a long slope compare with the same antenna mounted above flat ground?
- A.The main lobe takeoff angle increases in the downhill direction
- B.The main lobe takeoff angle decreases in the downhill direction (correct answer)
- C.The horizontal beamwidth decreases in the downhill direction
- D.The horizontal beamwidth increases in the uphill direction
WhyA horizontally polarized antenna mounted above a long slope has its main lobe takeoff angle decrease in the downhill direction, compared to the same antenna over flat ground. A horizontally polarized antenna mounted above a long downward slope has its main lobe's takeoff angle decrease in the downhill direction compared to the same antenna over flat ground, since the sloping terrain effectively increases the antenna's height above the ground in that direction, answer B. The takeoff angle doesn't increase in the downhill direction, and horizontal beamwidth isn't the characteristic primarily affected by sloping terrain this way.
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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