Antenna Gain, Pattern and Polarity.
Three important electrical characteristics of an antenna are:- Antenna pattern, Gain, and Polarity. Lets discuss the three antenna properties in details.
Antenna Gain: -
Its a measure of signal strength in direction of transmission. This gain is in proportion to the signal strength when antenna is
In other words antenna gain for Omni-directional antenna is equal in all directions. For reference this gain is equal to 1 or 0 dB.
For directional antennas the antenna gain will be higher and will be focused in a narrower beam.
The amount of power that is received by the receiving antenna is proportional to: Transmitter Power x Transmit Antenna Gain x Receive Antenna Gain
As the transmission between antennas involve electromagnetic energy which is not evenly distributed in all directions. The varying intensities of
an antenna’s radiated power in various directions is called the pattern of the antenna.
Complete antenna patterns are three-dimensional, although often only a two-dimensional slice of the pattern is shown when all the antennas of interest are located in roughly the same horizontal plane, along the ground rather than above or below one another.