What can cause signal diffraction?

Signal diffraction occurs when waves encounter obstacles or openings in their path. This phenomenon allows waves to bend around corners or spread out after passing through narrow openings. The extent of diffraction is influenced by the size of the obstacle or opening relative to the wavelength of the signal. When the dimensions are comparable, significant diffraction occurs, which can lead to a change in the signal's strength and direction, affecting overall communication effectiveness.

Smooth surfaces alone do not inherently create diffraction; instead, irregularities or specific types of openings play a critical role in this process. High-frequency waves tend to diffract less than lower frequency waves, particularly with smaller openings or obstacles, which limits their effectiveness in scenarios requiring significant diffraction. Free space propagation allows waves to travel without interaction with obstacles, hence there is no diffraction occurring in a typical free-space environment.

Thus, obstacles and openings are the key elements that facilitate diffraction, highlighting the importance of environmental factors in radio wave propagation.