The omnidirectional antenna will transmit signals in all directions, and the signal can be received from front to back. The directional antenna is like a bowl-shaped reflecting surface behind the antenna. The signal can only be transmitted to the front. The signal that is directed to the back is blocked and reflected by the reflecting surface. To the front, the front signal strength is enhanced.
An omnidirectional antenna, in general, the smaller the lobe width, the greater the gain. The omnidirectional antenna is generally used in a communication system with a close distance, a large coverage range, and a low price. The gain is generally below 9dB.
