Identify a key characteristic of a directional antenna.

A directional antenna is specifically designed to concentrate the radio frequency energy in a particular direction, which enhances signal strength and improves communication range in that direction. This characteristic allows for more efficient communication by reducing interference from signals coming from other directions and maximizing the signal strength for the intended receiving station.

Other characteristics like operating at a lower frequency or amplifying all incoming signals do not accurately describe directional antennas. Instead, directional antennas function more effectively at high frequencies, and they do not amplify signals indiscriminately; rather, they selectively enhance signals from their focused direction. Additionally, while power requirements can vary, the primary function of a directional antenna is based on its design to focus energy rather than on minimal power usage.