How does terrain affect line of sight communications?

Terrain plays a significant role in line of sight communications by potentially obstructing the direct path signal. When there are hills, mountains, buildings, or other obstacles present, they can block or reflect radio waves, leading to signal degradation or complete loss of communication. This physical obstruction means that the transmitting and receiving antennas may no longer be able to "see" each other, which is critical for effective line of sight communication. In scenarios where the terrain is uneven or contains large structures, the challenge of maintaining a clear signal becomes evident, emphasizing the importance of understanding terrain when designing communication systems.