The antenna is the most important piece of equipment in an RF communication system.

It does not matter how powerful the transmitter or how sensitive the receiver, without a good antenna the propagation

and collection of signals will suffer and hence limit the communication range.

Radiation pattern of antennas with various gains. Note that antennas with more gain have a narrower radiation pattern.

Lower gain antennas are more suitable for hilly terrain where reception does not depend on the angle of the antenna.