Explain how a directional antenna pattern can increase communication range while reducing interference.

• A. Directional antennas reduce gain overall.
• B. A directional antenna concentrates energy in a specific direction, increasing gain toward the target and reducing radiation in other directions, improving SNR.
• C. They only work outdoors.
• D. They increase interference.

Answer: (B)

A directional antenna concentrates radiated energy in a specific direction, which boosts the gain toward the target and reduces radiation elsewhere. That focused gain improves the link budget, so the signal arriving at the receiver is stronger, allowing communication to reach farther distances. At the same time, because much less energy is radiated toward non-target directions, potential interference from other transmitters in those directions is reduced, which improves the signal-to-noise ratio at the receiver. In practice the main lobe provides most of the useful power to the intended link while side lobes carry much less power, and nulls can further suppress radiation toward known interferers. This combination of higher gain in the desired direction and lower radiation elsewhere explains the increased range with reduced interference.