The signal distribution of receiving antennas offers the greatest potential for system performance improvement. Receiving and transmitting antennas are available as omnidirectional and directional variants.
For receiving, omnidirectional antennas are often recommended for indoor use because the RF signal is reflected off of the walls and ceiling. When working outside, one should choose a directional antenna since there are usually little to no reflections outdoors, and this directivity will help to stabilize the signal.
In general, it is wise to keep an “antenna tool box” that contains both omnidirectional and directional antennas for use in critical RF situations, since they transmit and receive signals differently.
Omnidirectional antennas transmit or receive the signal by providing uniform radiation or response only in one reference plane, which is usually the horizontal one parallel to the earth’s surface. The omnidirectional antenna has no preferred direction and cannot differentiate between a wanted and an unwanted signal.
If a directional antenna is used, it will transmit or receive the signal in the path it is pointing towards. The most common types are the yagi antenna and the log-periodic antenna, which are often wide range frequency antennas covering the whole UHF range.
In an outdoor venue, the desired signal can be received and the unwanted signal from a TV station can be rejected to a certain degree by choosing the correct antenna position. A directional antenna also transmits or receives only in one plane, like an omnidirectional antenna.
Several types of omnidirectional and directional antennas also exist for specific conditions. The telescopic antenna is an omnidirectional antenna and often achieves a wide range (450-960 MHz).