Which structure can interfere with radio transmissions?

Which structure can interfere with radio transmissions?

• A. Steel bridges
• B. Wooden fences
• C. Concrete sidewalks
• D. Brick buildings

Answer: (A)

Metal structures disrupt radio transmissions because they are conductors that reflect, absorb, and re-radiate RF energy. A steel bridge is a particularly strong example: its large, continuous conductive surface can block or deflect signals, create shadowed areas, and cause multipath where reflected signals arrive at the receiver at different times. This can distort the antenna pattern, change impedance, and lead to fades or dead zones nearby or behind the bridge. Wooden fences, being non-conductive, don’t reflect RF in the same way and typically pose far less interference. Brick buildings, while capable of attenuating and diffusing signals, don’t offer the same broad, strong reflection characteristics as a large steel structure. Concrete sidewalks also don’t provide the same large conductive surface as steel; they may attenuate signals somewhat but are not as disruptive to radio transmissions.

Metal structures disrupt radio transmissions because they are conductors that reflect, absorb, and re-radiate RF energy. A steel bridge is a particularly strong example: its large, continuous conductive surface can block or deflect signals, create shadowed areas, and cause multipath where reflected signals arrive at the receiver at different times. This can distort the antenna pattern, change impedance, and lead to fades or dead zones nearby or behind the bridge.

Wooden fences, being non-conductive, don’t reflect RF in the same way and typically pose far less interference. Brick buildings, while capable of attenuating and diffusing signals, don’t offer the same broad, strong reflection characteristics as a large steel structure. Concrete sidewalks also don’t provide the same large conductive surface as steel; they may attenuate signals somewhat but are not as disruptive to radio transmissions.