What does the gain of an antenna refer to?

The gain of an antenna refers to the increase in signal strength in a specified direction. When an antenna is designed with gain, it typically focuses the radiated power in a particular direction, which enhances the signal strength received or transmitted along that path compared to an isotropic radiator, which radiates energy uniformly in all directions.

This directional property allows antennas with gain to be more effective in communication over specific distances or towards particular stations, making them popular choices in various radio applications. The gain is usually expressed in decibels (dB) relative to a reference antenna, indicating how much better the antenna will perform in the desired direction compared to an ideal isotropic (non-directional) antenna.

Understanding antenna gain is crucial as it directly influences communication range and link quality in ham radio operations.