When buying an antenna there are a few aspects to consider to ensure you get the antenna that is right for you. Gain and dBi might sound confusing at first but are important considerations in choosing the right antenna. The gain of an antenna is simply the measure of an antenna’s ability to direct or concentrate radio frequency energy in a particular direction or pattern, with dBi being the unit of measure.
It is important to consider which gain is right for your application, and there are a few questions you can ask to determine this. Firstly, where will you be using your antenna? Is the terrain flat and expansive or hilly and rugged? Will it primarily be used for on-road use, or 4WDing? The answers to these questions can help point you in the right direction.