How does the ultra high frequency band limit communications?

The ultra high frequency (UHF) band is characterized by its ability to propagate in ways that are influenced by line-of-sight conditions and physical obstacles, such as buildings and terrain. This frequency range is typically utilized for various forms of communication, including television, mobile phones, and radio.

UHF waves have shorter wavelengths, which means they tend to travel in straight lines and are more likely to be obstructed by obstacles. As a result, their effective communication range is generally shorter compared to lower frequency bands, which can reflect off the ionosphere (like those used in sky wave propagation) or travel over longer distances (such as ground waves).

This limitation is particularly pronounced beyond the horizon, where UHF signals struggle to maintain their strength. The curvature of the Earth combined with obstructions creates a communication barrier that confines UHF transmissions to more localized areas. Therefore, this band is primarily effective for communications within shorter distances.