Which effect allows radio signals to travel beyond obstructions between the transmitting and receiving stations?

Which effect allows radio signals to travel beyond obstructions between the transmitting and receiving stations?

• A. Knife-edge diffraction
• B. Multi-path propagation
• C. Groundwave propagation
• D. Intersymbol interference

Answer: (A)

Knife-edge diffraction is a phenomenon that occurs when radio waves encounter an obstacle, such as a building or hill, that has a sharp edge. When the waves pass the edge of the obstacle, they bend or diffract around it, allowing the signal to continue propagating beyond the obstruction. This effect enables radio communications to function effectively even when there are physical barriers between the transmitting and receiving stations. In contrast, multi-path propagation refers to the situation where signals arrive at the receiver via multiple paths, often leading to constructive or destructive interference, but it does not inherently allow signals to bypass obstacles. Groundwave propagation involves radio waves traveling along the surface of the Earth, typically over shorter distances and may not overcome significant obstructions. Intersymbol interference relates to the distortion that affects signal quality in digital communications and does not pertain to signal propagation around obstacles.

Knife-edge diffraction is a phenomenon that occurs when radio waves encounter an obstacle, such as a building or hill, that has a sharp edge. When the waves pass the edge of the obstacle, they bend or diffract around it, allowing the signal to continue propagating beyond the obstruction. This effect enables radio communications to function effectively even when there are physical barriers between the transmitting and receiving stations.

In contrast, multi-path propagation refers to the situation where signals arrive at the receiver via multiple paths, often leading to constructive or destructive interference, but it does not inherently allow signals to bypass obstacles. Groundwave propagation involves radio waves traveling along the surface of the Earth, typically over shorter distances and may not overcome significant obstructions. Intersymbol interference relates to the distortion that affects signal quality in digital communications and does not pertain to signal propagation around obstacles.