Omni directional antenna:

Receives signal evenly from all directions. Transmits signal evenly in all directions. An omni directional antenna provides a 360 degree radiation pattern. Typically in the form of a vertical rod although other shapes are available. Commonly used inside structures (buildings) to provide best possible reception from all directions. Also used outdoors at Receiver to communicate with Transmitters that are geographically spread out over the terrain. An omni directional antenna is typically used at each of the Transmitters. Ideal for point-to-multipoint communications with transmitters.