Chapter 2

Is a high gain antenna more powerful than a low gain antenna?

No. In absolute terms there is no such thing as one antenna that is more powerful than another because antennas are passive devices (radiators) and they do not create energy, however, antennas are most often rated in dB gain and as such, most people believe that a high gain antenna is better or more powerful than a low gain: for example a 3db gain antenna versus a 0db gain antenna.

In reality, there is no energy increase with a gain antenna. An antenna without gain (0db) radiates energy in all directions equally and antenna with gain redirects or concentrates energy in a certain direction and the gain performance is measured in the direction of the energy concentration. A vertically mounted high gain antenna will concentrate energy more parallel to the earth and will generally perform better when the tower is unobstructed and located on the horizon (oceans, lakes, deserts.), however its vertical radiation will be lower than a low gain antenna.

In very simplistic terms it can be said that a low gain cellular antenna will perform better in geographic areas where signal is bouncing, reflecting or is generally located vertically from the antenna mast (cities, mountains, areas with obstructions). A vertically mounted high gain antenna will direct more of the energy that it radiates parallel to the earth and less energy toward the sky. This antenna will perform better when the tower is unobstructed and located on the horizon (oceans, lakes, deserts). It is advisable for people who travel to remote areas of poor cellular signal and varying geographic terrain to have both types of antennas because of this phenomenon.