For outdoor long-distance point-to-point backhaul, the antenna of ( ) should be selected.

Question

Options

• AHigh gain, small lobe width
• BHigh gain, large lobe width
• Comnidirectional
• DLow gain, large lobe width

• A
  83% (39)
• B
  11% (5)
• C
  4% (2)
• D
  2% (1)

Explanation

Option A is correct because long-distance point-to-point backhaul requires concentrating RF energy into a tight, focused beam aimed precisely at the distant endpoint - high gain achieves the necessary signal strength over kilometers, while small lobe width (narrow beamwidth) minimizes wasted energy in unwanted directions, maximizing effective range and reducing interference.

Why the distractors fail:

• B (High gain, large lobe width): These properties are physically contradictory - gain and beamwidth are inversely related; you cannot have both simultaneously in a real antenna. A wider lobe scatters energy away from the target.
• C (Omnidirectional): Radiates equally in all directions, which is ideal for broadcasting to many clients but wastes the vast majority of power on directions where no receiver exists - devastating for long-range links.
• D (Low gain, large lobe width): The worst combination for backhaul - weak signal that also spreads in the wrong directions; this describes a short-range, multi-user scenario, not a backbone link.

Memory tip: Think of it like a flashlight vs. a laser pointer. For long-distance point-to-point, you want the laser (high gain = bright, small lobe = tight beam) - not a flashlight spreading light everywhere.

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