Advanced Qualification · A-007 Feedlines and matching · A-007-008-006
How can the approximate beamwidth of a beam antenna be determined?
- ANote the two points where the signal strength is down 3 dB from the maximum signal point and compute the angular
- BDraw two imaginary lines through the ends of the elements and measure the angle between the lines
- CMeasure the ratio of the signal strengths of the radiated power lobes from the and side of the antenna
- DMeasure the ratio of the signal strengths of the radiated power lobes from the and rear of the antenna
Correct answer: A — Note the two points where the signal strength is down 3 dB from the maximum signal point and compute the angular. From the official ISED question bank, verified word for word.
Why
Beamwidth is the angular width of the main lobe where the signal remains strong, defined specifically by the points where power drops to half its peak value. The full explanation — and one for every question — is in Pro.
Practise this section
Feedlines and matching is section A-007 of the Advanced exam: Feedlines and matching at the advanced level: transmission line theory, impedance transformation, stubs and matching networks.
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